Gold(III), Mercury(II), and Palladium(II) Complexes of a Series of Isomeric Bis(mono- and dialkoxyphenyl)pyridines: Introduction of Gold through Transmetalation and Catalysis

A series of isomeric bis-2,6-(monoalkoxyphenyl)pyridine and bis-2,6-(dialkoxyphenyl)pyridine ligands were synthesized and characterized. In order to prepare their chlorogold(III) complexes, intermediate chloromercury(II) complexes were first prepared, but unlike observations from previous studies where they were obtained impure and at best in moderate yield, here pure complexes were synthesized, many in rather high yields. Depending on the substitution pattern of the alkoxy chains on the ligands, mono- and/or dimercurated complexes were obtained, characterized by 1H, 13C{1H}, and 199Hg NMR spectroscopy as well as, in several cases, by X-ray crystallography. Factors that may explain this unusual reactivity are discussed. In most cases, transmetalation to the related chlorogold(III) complex proceeded smoothly, although lower yields were obtained when starting from doubly mercurated precursors. Prompted by the propensity of these ligands to mercurate, attempts were made to effect direct auration, but none was successful. However, dimeric, orthometalated complexes of palladium(II) could be prepared and were also amenable to transmetalation to the chlorogold(III) complex, providing for a mercury-free synthesis.

Do school grades matter for growing up? Testing the predictive validity of school performance for outcomes in emerging adulthood

In putatively meritocratic societies, doing well in school is a pivotal precondition for accessing further and higher education, which, in turn, has a pervasive, long-term influence on adulthood development. Yet, doing well in school may also predict "real-life success" outside formal education settings and independent of the educational qualifications that a person attains. Such predictions are likely to become salient during emerging adulthood, a life period characterized by career explorations and social-emotional adjustment. Here, we tested the predictive validity of end-of-compulsory school grades at age 16 years in a U.K.-representative population cohort sample of up to N = 6,488, who were born between 1994 and 1996, for a broad range of occupational, financial, and social-emotional outcomes at age 23. End-of-compulsory school performance accounted for 1%-20% of the variance across occupational, financial, and social-emotional outcomes in emerging adulthood. Educational attainment attenuated these associations only slightly, with school grades at age 16 accounting for variance in emerging adulthood outcomes independent of later educational attainment. We found that school grades were equally predictive for boys' and girls' outcomes. In children from lower family socioeconomic status (SES) backgrounds, school grades were more predictive of their educational attainment, financial attitudes, and anxiety compared to higher SES children, with varying effect sizes (i.e., 0.3%-4.2%). Our findings suggest that school-leaving grades facilitate the successful transition from adolescence to adulthood, independent of educational attainment, and that they might enable children from low-SES families to compensate for some of their background disadvantages. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Unveiling Mechanistic Complexity in Manganese-Catalyzed C-H Bond Functionalization Using IR Spectroscopy Over 16 Orders of Magnitude in Time

ConspectusAn understanding of the mechanistic processes that underpin reactions catalyzed by 3d transition metals is vital for their development as potential replacements for scarce platinum group metals. However, this is a significant challenge because of the tendency of 3d metals to undergo mechanistically diverse pathways when compared with their heavier congeners, often as a consequence of one-electron transfer reactions and/or intrinsically weaker metal-ligand bonds. We have developed and implemented a new methodology to illuminate the pathways that underpin C-H bond functionalization pathways in reactions catalyzed by Mn-carbonyl compounds. By integrating measurements performed on catalytic reactions with in situ reaction monitoring and state-of-the-art ultrafast spectroscopic methods, unique insight into the mode of action and fate of the catalyst have been obtained.Using a combination of time-resolved spectroscopy and in situ low-temperature NMR studies, we have shown that photolysis of manganese-carbonyl precatalysts results in rapid (<5 ps) CO dissociation─the same process that occurs under thermal catalytic conditions. This enabled the detection of the key states relevant to catalysis, including solvent and alkyne complexes and their resulting transformation into manganacycles, which results from a migratory insertion reaction into the Mn-C bond. By systematic variation of the substrates (many of which are real-world structurally diverse substrates and not simple benchmark systems) and quantification of the resulting rate constants for the insertion step, a universal model for this migratory insertion process has been developed. The time-resolved spectroscopic method gave insight into fundamental mechanistic pathways underpinning other aspects of modern synthetic chemistry. The most notable was the first direct experimental observation of the concerted metalation deprotonation (CMD) mechanism through which carboxylate groups are able to mediate C-H bond activation at a metal center. This step underpins a host of important synthetic applications. This study demonstrated how the time-resolved multiple probe spectroscopy (TRMPS) method enables the observation of mechanistic process occurring on time scales from several picoseconds through to μs in a single experiment, thereby allowing the sequential observation of solvation, ligand substitution, migratory insertion, and ultimate protonation of a Mn-C bond.These studies have been complemented by an investigation of the "in reaction flask" catalyst behavior, which has provided additional insight into new pathways for precatalyst activation, including evidence that alkyne C-H bond activation may occur before heterocycle activation. Crucial insight into the fate of the catalyst species showed that excess water played a key role in deactivation to give higher-order hydroxyl-bridged manganese carbonyl clusters, which were independently found to be inactive. Traditional in situ IR and NMR spectroscopic analysis on the second time scale bridges the gap to the analysis of real catalytic reaction systems. As a whole, this work has provided unprecedented insight into the processes underpinning manganese-catalyzed reactions spanning 16 orders of magnitude in time.

A Modular Strategy for the Synthesis of Macrocycles and Medium-Sized Rings via Cyclization/Ring Expansion Cascade Reactions

Macrocycles and medium-sized rings are important in many scientific fields and technologies but are hard to make using current methods, especially on a large scale. Outlined herein is a strategy by which functionalized macrocycles and medium-sized rings can be prepared using cyclization/ring expansion (CRE) cascade reactions, without resorting to high dilution conditions. CRE cascade reactions are designed to operate exclusively via kinetically favorable 5-7-membered ring cyclization steps; this means that the problems typically associated with classical end-to-end macrocyclization reactions are avoided. A modular synthetic approach has been developed to facilitate the simple assembly of the requisite linear precursors, which can then be converted into an extremely broad range of functionalized macrocycles and medium-sized rings using one of nine CRE protocols.

Evidence for Suzuki-Miyaura cross-couplings catalyzed by ligated Pd3-clusters: from cradle to grave

Pdn clusters offer unique selectivity and exploitable reactivity in catalysis. Understanding the behavior of Pdn clusters is thus critical for catalysis, applied synthetic organic chemistry and greener outcomes for precious Pd. The Pd3 cluster, [Pd3(μ-Cl)(μ-PPh2)2(PPh3)3][Cl] (denoted as Pd3Cl2), which exhibits distinctive reactivity, was synthesized and immobilized on a phosphine-functionalized polystyrene resin (denoted as immob-Pd3Cl2). The resultant material served as a tool to study closely the role of Pd3 clusters in a prototypical Suzuki-Miyaura cross-coupling of 4-fluoro-1-bromobenzene and 4-methoxyphenyl boronic acid at varying low Pd ppm concentrations (24, 45, and 68 ppm). Advanced heterogeneity tests such as Hg poisoning and the three-phase test showed that leached mononuclear or nanoparticulate Pd are unlikely to be the major active catalyst species under the reaction conditions tested. EXAFS/XANES analysis from (pre)catalyst and filtered catalysts during and after catalysis has shown the intactness of the triangular structure of the Pd3X2 cluster, with exchange of chloride (X) by bromide during catalytic turnover of bromoarene substrate. This finding is further corroborated by treatment of immob-Pd3Cl2 after catalyzing the Suzuki-Miyaura reaction with excess PPh3, which releases the cluster from the polymer support and so permits direct observation of [Pd3(μ-Br)(μ-PPh2)2(PPh3)3]+ ions by ESI-MS. No evidence is seen for a proposed intermediate in which the bridging halogen on the Pd3 motif is replaced by an aryl group from the organoboronic acid, i.e. formed by a transmetallation-first process. Our findings taken together indicate that the 'Pd3X2' motif is an active catalyst species, which is stabilized by being immobilized, providing a more robust Pd3 cluster catalyst system. Non-immobilized Pd3Cl2 is less stable, as is followed by stepwise XAFS of the non-immobilized Pd3Cl2, which gradually changes to a species consistent with 'Pdx(PPh3)y' type material. Our findings have far-reaching future implications for Pd3 cluster involvement in catalysis, showing that immobilization of Pd3 cluster species offers advantages for rigorous mechanistic examination and applied chemistries.

Trends in mental health before and after the onset of the COVID-19 pandemic: a longitudinal survey of a conflict-affected population in Colombia

BACKGROUND

Focusing on the Meta region in Colombia, we investigated the relationship between mental health, the COVID-19 pandemic, and social determinants of health influenced by over five decades of civil conflict. We studied the post-2016 peace agreement trends in mental health for the population of Meta, before and after the local onset of the pandemic.

METHOD

We conducted three rounds of a longitudinal health survey in years 2018 with N = 1309 (Women = 709; Men = 600); 2019 with N = 1106 (Women = 597; Men = 509); and 2020 with N = 905 (Women = 499; Men = 406). We measured mental health through the Self-Report Questionnaire (SRQ-20), investigating population trends in the average SRQ score and SRQ-positive frequency (SRQ + , indicating positive tendency towards experiencing mental health disorders).

RESULTS

Between 2018 and 2020, there were reductions in the mean SRQ-20 score by 1.74 points (95% CI -2.30 to -1.18) and in SRQ + frequency by 15 percentage points (95% CI -21.0 to -9.0) for the Meta population. Yet specific subgroups have become more vulnerable to mental illness during the pandemic, for example older age groups (e.g., increase in mean SRQ score among over 60 s by 2.49 points, 95% CI 0.51 to 4.46) and people living with children younger than five years-old (e.g., increase in mean SRQ score by 0.64 points, 95% CI 0.07 to 1.20). Increased mental health vulnerability among specific subgroups may be related to differences in the likelihood of knowing people who tested positive for COVID-19 or died from itf having been in quarantine.

CONCLUSION

Our findings support the importance of public policies in Colombia (and other low- and middle-income countries) that address the social determinants of mental illness whose influence was likely exacerbated by the pandemic, including persistent job insecurity leading to work and financial pressures, and inadequate support networks for isolated individuals and vulnerable caregivers.

Cross aldol OPAL bioconjugation outcompetes intramolecular hemiaminal cyclisation of proline adjacent N-terminal α-oxo aldehydes at acidic pH

Novel methods to construct small molecule-protein bioconjugates are integral to the development of new biomedicines for a variety of diseases. C-C linked bioconjugates are increasingly desirable in this application due to their in vivo stability and can be accessed through cross aldol bioconjugation of reactive α-oxo aldehyde handles easily introduced at the N-terminus of proteins by periodate oxidation. We previously developed an organocatalyst-mediated protein aldol ligation (OPAL) for chemical modification of these reactive aldehydes, but the efficiency of this method was limited when a proline residue was directly adjacent to the N-terminus due to intramolecular hemiaminal formation. Herein we explore the competition between this cyclisation and the OPAL modification and demonstrate bioconjugation can be favoured through use of acidic pH for both oxidation and OPAL, and optimisation of reaction conditions and organocatalyst. We then showcase the utility of this acidic-OPAL in modification of the cholera toxin B-subunit (CTB), a homo-pentameric protein of biomedical promise.

Metal-Mediated Catalytic Polarization Transfer from para Hydrogen to 3,5-Dihalogenated Pyridines

The neutral catalysts [IrCl(H)2(NHC)(substrate)2] or [IrCl(H)2(NHC)(substrate)(sulfoxide)] are used to transfer polarization from para hydrogen (pH2) to 3,5-dichloropyridine and 3,5-dibromopyridine substrates. This is achieved in a rapid, reversible, and low-cost process that relies on ligand exchange within the active catalyst. Notably, the sulfoxide-containing catalyst systems produced NMR signal enhancements between 1 and 2 orders of magnitude larger than its unmodified counterpart. Consequently, this signal amplification by reversible exchange hyperpolarization method can boost the 1H, 13C, and 15N nuclear magnetic resonance (NMR) signal intensities by factors up to 4350, 1550, and 46,600, respectively (14.0, 1.3, and 15.4% polarization). In this paper, NMR and X-ray crystallography are used to map the evolution of catalytically important species and provide mechanistic rational for catalytic efficiency. Furthermore, applications in spontaneous radiofrequency amplification by stimulated emission and NMR reaction monitoring are also shown.

Co-occurring microflora and mucin drive Pseudomonas aeruginosa diversification and pathoadaptation

While several environmental factors contribute to the evolutionary diversification of the pathogenic bacterium Pseudomonas aeruginosa during cystic fibrosis lung infections, relatively little is known about the impact of the surrounding microbiota. By using in vitro experimental evolution, we show that the presence of Stenotrophomonas maltophilia, Staphylococcus aureus, or them both, prevent the evolution of loss of virulence, which repeatedly occurs in the absence of these species due to mutations in regulators of the Pseudomonas Quinolone Signal quorum sensing system, vqsM and pqsR. Moreover, the strength of the effect of co-occurring species is attenuated through changes in the physical environment by the addition of mucin, resulting in selection for phenotypes resembling those evolved in the absence of the co-occurring species. Together, our findings show that variation in mucosal environment and the surrounding polymicrobial environment can determine the evolutionary trajectory of P. aeruginosa, partly explaining its diversification and pathoadaptation from acute to chronic phenotype during cystic fibrosis lung infections.

The Role of Polyphenolic Antioxidants from Tea and Rosemary in the Hydroxyl Radical Oxidation of N-Acetyl Alanine

In dead biological tissues such as human hair, the ability of antioxidants to minimise autoxidation is determined by their chemical reactions with reactive oxygen species. In order to improve our understanding of factors determining such antioxidant properties, the mechanistic chemistry of four phenolic antioxidants found in tea and rosemary extracts (epicatechin, epigallocatechin gallate, rosmarinic and carnosic acids) has been investigated. The degradation of N-acetyl alanine by photochemically generated hydroxyl radicals was used as a model system. A relatively high concentration of the antioxidants (0.1 equivalent with respect to the substrate) tested the ability of the antioxidants to intercept both initiating hydroxyl radicals (preventive action) and propagating peroxyl radicals (chain-breaking action). LC-MS data showed the formation of hydroxylated derivatives, quinones and hydroperoxides of the antioxidants. The structure of the assignment was aided by deuterium exchange experiments. Tea polyphenolics (epicatechin and epigallocatechin gallate) outperformed the rosemary compounds in preventing substrate degradation and were particularly effective in capturing the initiating radicals. Carnosic acid was suggested to act mostly as a chain-breaking antioxidant. All of the antioxidants except for rosmarinic acid generated hydroperoxides which was tentatively ascribed to the insufficient lability of the benzylic C-H bond of rosmarinic acid.

Opening a Pandora's Flask on a Prototype Catalytic Direct Arylation Reaction of Pentafluorobenzene: The Ag2CO3/Pd(OAc)2/PPh3 System

Direct C-H functionalization reactions have opened new avenues in catalysis, removing the need for prefunctionalization of at least one of the substrates. Although C-H functionalization catalyzed by palladium complexes in the presence of a base is generally considered to proceed by the CMD/AMLA-6 mechanism, recent research has shown that silver(I) salts, frequently used as bases, can function as C-H bond activators instead of (or in addition to) palladium(II). In this study, we examine the coupling of pentafluorobenzene 1 to 4-iodotoluene 2a (and its analogues) to form 4-(pentafluorophenyl)toluene 3a catalyzed by palladium(II) acetate with the commonplace PPh3 ligand, silver carbonate as base, and DMF as solvent. By studying the reaction of 1 with Ag2CO3/PPh3 and with isolated silver (triphenylphosphine) carbonate complexes, we show the formation of C-H activation products containing the Ag(C6F5)(PPh3)n unit. However, analysis is complicated by the lability of the Ag-PPh3 bond and the presence of multiple species in the solution. The speciation of palladium(II) is investigated by high-resolution-MAS NMR (chosen for its suitability for suspensions) with a substoichiometric catalyst, demonstrating the formation of an equilibrium mixture of Pd(Ar)(κ1-OAc)(PPh3)2 and [Pd(Ar)(μ-OAc)(PPh3)]2 as resting states (Ar = Ph, 4-tolyl). These two complexes react stoichiometrically with 1 to form coupling products. The catalytic reaction kinetics is investigated by in situ IR spectroscopy revealing a two-term rate law and dependence on [Pdtot/nPPh3]0.5 consistent with the dissociation of an off-cycle palladium dimer. The first term is independent of [1], whereas the second term is first order in [1]. The observed rates are very similar with Pd(PPh3)4, Pd(Ph)(κ1-OAc)(PPh3)2, and [Pd(Ph)(μ-OAc)(PPh3)]2 catalysts. The kinetic isotope effect varied significantly according to conditions. The multiple speciation of both AgI and PdII acts as a warning against specifying the catalytic cycles in detail. Moreover, the rapid dynamic interconversion of AgI species creates a level of complexity that has not been appreciated previously.

Direct Cyclopalladation of Fluorinated Benzyl Amines by Pd3(OAc)6: The Coexistence of Multinuclear Pdn Reaction Pathways Highlights the Importance of Pd Speciation in C-H Bond Activation

Palladacycles are key intermediates in catalytic C-H bond functionalization reactions and important precatalysts for cross-couplings. It is commonly believed that palladacycle formation occurs through the reaction of a substrate bearing a C-H bond ortho to a suitable metal-directing group for interaction with, typically, mononuclear "Pd(OAc)2" species, with cyclopalladation liberating acetic acid as the side product. In this study, we show that N,N-dimethyl-fluoro-benzyl amines, which can be cyclopalladated either ortho or para to fluorine affording two regioisomeric products, can occur by a direct reaction of Pd3(OAc)6, proceeding via higher-order cyclopalladated intermediates. Regioselectivity is altered subtly depending on the ratio of substrate:Pd3(OAc)6 and the solvent used. Our findings are important when considering mechanisms of Pd-mediated reactions involving the intermediacy of palladacycles, of particular relevance in catalytic C-H bond functionalization chemistry.

Dual spin max pooling convolutional neural network for solar cell crack detection

This paper presents a solar cell crack detection system for use in photovoltaic (PV) assembly units. The system utilizes four different Convolutional Neural Network (CNN) architectures with varying validation accuracy to detect cracks, microcracks, Potential Induced Degradations (PIDs), and shaded areas. The system examines the electroluminescence (EL) image of a solar cell and determines its acceptance or rejection status based on the presence and size of the crack. The proposed system was tested on various solar cells and achieved a high degree of accuracy, with an acceptance rate of up to 99.5%. The system was validated with thermal testing using real-world cases, such as shaded areas and microcracks, which were accurately predicted by the system. The results show that the proposed system is a valuable tool for evaluating the condition of PV cells and can lead to improved efficiency. The study also shows that the proposed CNN model outperforms previous studies and can have significant implications for the PV industry by reducing the number of defective cells and improving the overall efficiency of PV assembly units.

A systematic review of non-coding RNA genes with differential expression profiles associated with autism spectrum disorders

AIMS

To identify differential expression of shorter non-coding RNA (ncRNA) genes associated with autism spectrum disorders (ASD).

BACKGROUND

ncRNA are functional molecules that derive from non-translated DNA sequence. The HUGO Gene Nomenclature Committee (HGNC) have approved ncRNA gene classes with alignment to the reference human genome. One subset is microRNA (miRNA), which are highly conserved, short RNA molecules that regulate gene expression by direct post-transcriptional repression of messenger RNA. Several miRNA genes are implicated in the development and regulation of the nervous system. Expression of miRNA genes in ASD cohorts have been examined by multiple research groups. Other shorter classes of ncRNA have been examined less. A comprehensive systematic review examining expression of shorter ncRNA gene classes in ASD is timely to inform the direction of research.

METHODS

We extracted data from studies examining ncRNA gene expression in ASD compared with non-ASD controls. We included studies on miRNA, piwi-interacting RNA (piRNA), small NF90 (ILF3) associated RNA (snaR), small nuclear RNA (snRNA), small nucleolar RNA (snoRNA), transfer RNA (tRNA), vault RNA (vtRNA) and Y RNA. The following electronic databases were searched: Cochrane Library, EMBASE, PubMed, Web of Science, PsycINFO, ERIC, AMED and CINAHL for papers published from January 2000 to May 2022. Studies were screened by two independent investigators with a third resolving discrepancies. Data was extracted from eligible papers.

RESULTS

Forty-eight eligible studies were included in our systematic review with the majority examining miRNA gene expression alone. Sixty-four miRNA genes had differential expression in ASD compared to controls as reported in two or more studies, but often in opposing directions. Four miRNA genes had differential expression in the same direction in the same tissue type in at least 3 separate studies. Increased expression was reported in miR-106b-5p, miR-155-5p and miR-146a-5p in blood, post-mortem brain, and across several tissue types, respectively. Decreased expression was reported in miR-328-3p in bloods samples. Seven studies examined differential expression from other classes of ncRNA, including piRNA, snRNA, snoRNA and Y RNA. No individual ncRNA genes were reported in more than one study. Six studies reported differentially expressed snoRNA genes in ASD. A meta-analysis was not possible because of inconsistent methodologies, disparate tissue types examined, and varying forms of data presented.

CONCLUSION

There is limited but promising evidence associating the expression of certain miRNA genes and ASD, although the studies are of variable methodological quality and the results are largely inconsistent. There is emerging evidence associating differential expression of snoRNA genes in ASD. It is not currently possible to say whether the reports of differential expression in ncRNA may relate to ASD aetiology, a response to shared environmental factors linked to ASD such as sleep and nutrition, other molecular functions, human diversity, or chance findings. To improve our understanding of any potential association, we recommend improved and standardised methodologies and reporting of raw data. Further high-quality research is required to shine a light on possible associations, which may yet yield important information.

Enhancing 19F Benchtop NMR Spectroscopy by Combining para-Hydrogen Hyperpolarization and Multiplet Refocusing

Benchtop NMR spectrometers provide a promising alternative to high-field NMR for applications that are limited by instrument size and/or cost. ¹⁹F benchtop NMR is attractive due to the larger chemical shift range of ¹⁹F relative to ¹H and the lack of background signal in most applications. However, practical applications of benchtop ¹⁹F NMR are limited by its low sensitivity due to the relatively weak field strengths of benchtop NMR spectrometers. Here we present a sensitivity-enhancement strategy that combines SABRE (Signal Amplification By Reversible Exchange) hyperpolarization with the multiplet refocusing method SHARPER (Sensitive, Homogeneous, And Resolved PEaks in Real time). When applied to a range of fluoropyridines, SABRE-SHARPER achieves overall signal enhancements of up to 5700-fold through the combined effects of hyperpolarization and line-narrowing. This approach can be generalized to the analysis of mixtures through the use of a selective variant of the SHARPER sequence, selSHARPER. The ability of SABRE-selSHARPER to simultaneously boost sensitivity and discriminate between two components of a mixture is demonstrated, where selectivity is achieved through a combination of selective excitation and the choice of polarization transfer field during the SABRE step.

Siderophore-Linked Ruthenium Catalysts for Targeted Allyl Ester Prodrug Activation within Bacterial Cells

Due to rising resistance, new antibacterial strategies are needed, including methods for targeted antibiotic release. As targeting vectors, chelating molecules called siderophores that are released by bacteria to acquire iron have been investigated for conjugation to antibacterials, leading to the clinically approved drug cefiderocol. The use of small-molecule catalysts for prodrug activation within cells has shown promise in recent years, and here we investigate siderophore-linked ruthenium catalysts for the activation of antibacterial prodrugs within cells. Moxifloxacin-based prodrugs were synthesised, and their catalyst-mediated activation was demonstrated under anaerobic, biologically relevant conditions. In the absence of catalyst, decreased antibacterial activities were observed compared to moxifloxacin versus Escherichia coli K12 (BW25113). A series of siderophore-linked ruthenium catalysts were investigated for prodrug activation, all of which displayed a combinative antibacterial effect with the prodrug, whereas a representative example displayed little toxicity against mammalian cell lines. By employing complementary bacterial growth assays, conjugates containing siderophore units based on catechol and azotochelin were found to be most promising for intracellular prodrug activation.

Mechanically Robust Hybrid Gel Beads Loaded with "Naked" Palladium Nanoparticles as Efficient, Reusable, and Sustainable Catalysts for the Suzuki-Miyaura Reaction

The increase in demand for Pd and its low abundance pose a significant threat to its future availability, rendering research into more sustainable Pd-based technologies essential. Herein, we report Pd scavenging mechanically robust hybrid gel beads composed of agarose, a polymer gelator (PG), and an active low-molecular-weight gelator (LMWG) based on 1,3:2,4-dibenzylidenesorbitol (DBS), DBS-CONHNH ₂ . The robustness of the PG and the ability of the LMWG to reduce Pd(II) in situ to generate naked Pd(0) nanoparticles (PdNPs) combine within these gel beads to give them potential as practical catalysts for Suzuki-Miyaura cross-coupling reactions. The optimized gel beads demonstrate good reusability, green metrics, and most importantly the ability to sustain stirring, improving reaction times and energy consumption compared to previous examples. In contrast to previous reports, the leaching of palladium from these next-generation beads is almost completely eliminated. Additionally, for the first time, a detailed investigation of these Pd-loaded gel beads explains precisely how the nanoparticles are formed in situ without a stabilizing ligand. Further, detailed catalytic investigations demonstrate that catalysis occurs within the gel beads. Hence, these beads can essentially be considered as robust "nonligated" heterogeneous PdNP catalysts. Given the challenges in developing ligand-free, naked Pd nanoparticles as stable catalysts, these gel beads may have future potential for the development of easily used systems to perform chemical reactions in "kit" form.

Investigating the use of synthetic humic-like acid as a soil amendment for metal-contaminated soil

Humic acid can effectively bind several metals and is regarded as a promising soil amendment. In this study, a novel synthetic humic-like acid (SHLA) was applied as a soil amendment to immobilize metals (Cu, Zn, Ni, As) in a contaminated agricultural soil (pH 6.17 ± 0.11; total organic carbon 5.91 ± 0.40%; Cu 302.86 ± 3.97 mg/kg; Zn 700.45 ± 14.30 mg/kg; Ni 140.16 ± 1.59 mg/kg). With increasing additions of SHLA from 0 to 10% (w/w), the soil pH constantly decreased from 6.17 ± 0.11 to 4.91 ± 0.10 (p < 0.001), while both total organic carbon (from 6.10 ± 0.12% to 10.55 ± 0.18%) and water-soluble carbon content (from 171.01 ± 10.15 mg/kg to 319.18 ± 20.74 mg/kg) of soil significantly increased (p < 0.001). Based on the results of 0.01 M CaCl2-extractable concentration of different metals, SHLA could lower the bioavailability of Cu (from 1.26 ± 0.04 mg/kg to 0.55 ± 0.05 mg/kg), Zn (from 6.74 ± 0.12 mg/kg to 3.26 ± 0.23 mg/kg), and Ni (from 5.16 ± 0.07 mg/kg to 0.12 ± 0.02 mg/kg), but increase the bioavailability of As (from 0.31 ± 0.02 to 1.83 ± 0.09 mg/kg). The immobilization mechanisms of metals in soils amended with SHLA involved surface complexation, electrostatic attraction, and cation-π interaction. Overall, SHLA shows great potential as a soil amendment for cationic heavy metal immobilization.

Predictive Removal of Interfacial Defect-Induced Trap States between Titanium Dioxide Nanoparticles via Sub-Monolayer Zirconium Coating

First principles modeling of anatase TiO₂ surfaces and their interfacial contacts shows that defect-induced trap states within the band gap arise from intrinsic structural distortions, and these can be corrected by modification with Zr(IV) ions. Experimental testing of these predictions has been undertaken using anatase nanocrystals modified with a range of Zr precursors and characterized using structural and spectroscopic methods. Continuous-wave electron paramagnetic resonance (EPR) spectroscopy revealed that under illumination, nanoparticle-nanoparticle interfacial hole trap states dominate, which are significantly reduced after optimizing the Zr doping. Fabrication of nanoporous films of these materials and charge injection using electrochemical methods shows that Zr doping also leads to improved electron conductivity and mobility in these nanocrystalline systems. The simple methodology described here to reduce the concentration of interfacial defects may have wider application to improving the efficiency of systems incorporating metal oxide powders and films including photocatalysts, photovoltaics, fuel cells, and related energy applications.

Insight into ortho-boronoaldehyde conjugation via a FRET-based reporter assay

Ortho-boronoaldehydes react with amine-based nucleophiles with dramatically increased rates and product stabilities, relative to unfunctionalised benzaldehydes, leading to exciting applications across biological and material chemistry. We have developed a novel Förster resonance energy transfer (FRET)-based assay to provide key new insights into the reactivity of these boronoaldehydes, allowing us to track conjugation with unprecedented sensitivity and accuracy under standardised conditions. Our results highlight the key role played by reaction pH, buffer additives, and boronoaldehyde structure in controlling conjugation speed and stability, providing design criteria for further innovations and applications in the field.

Lessons from early life: understanding development to expand stem cells and treat cancers

Haematopoietic stem cell (HSC) self-renewal is a process that is essential for the development and homeostasis of the blood system. Self-renewal expansion divisions, which create two daughter HSCs from a single parent HSC, can be harnessed to create large numbers of HSCs for a wide range of cell and gene therapies, but the same process is also a driver of the abnormal expansion of HSCs in diseases such as cancer. Although HSCs are first produced during early embryonic development, the key stage and location where they undergo maximal expansion is in the foetal liver, making this tissue a rich source of data for deciphering the molecules driving HSC self-renewal. Another equally interesting stage occurs post-birth, several weeks after HSCs have migrated to the bone marrow, when HSCs undergo a developmental switch and adopt a more dormant state. Characterising these transition points during development is key, both for understanding the evolution of haematological malignancies and for developing methods to promote HSC expansion. In this Spotlight article, we provide an overview of some of the key insights that studying HSC development have brought to the fields of HSC expansion and translational medicine, many of which set the stage for the next big breakthroughs in the field.

Measuring RNA UNCG Tetraloop Refolding Dynamics Using Temperature-Jump/Drop Infrared Spectroscopy

Determining the structural dynamics of RNA and DNA is essential to understanding their cellular function, but direct measurement of strand association or folding remains experimentally challenging. Here we illustrate a temperature-jump/drop method able to reveal refolding dynamics. Time-resolved temperature-jump/drop infrared spectroscopy is used to measure the melting and refolding dynamics of a 12-nucleotide RNA sequence comprising a UACG tetraloop and a four-base-pair double-stranded GC stem, comparing them to an equivalent DNA (TACG) sequence. Stem-loop melting occurred an order of magnitude more slowly in RNA than DNA (6.0 ± 0.1 μs versus 0.8 ± 0.1 μs at 70 °C). In contrast, the refolding dynamics of both sequences occurred on similar time scales (200 μs). While the melting and refolding dynamics of RNA and DNA hairpins both followed Arrhenius temperature dependences, refolding was characterized by an apparent negative activation energy, consistent with a mechanism involving multiple misfolded intermediates prior to zipping of the stem base pairs.

Toward Optimizing and Understanding Reversible Hyperpolarization of Lactate Esters Relayed from para-Hydrogen

The SABRE-Relay hyperpolarization method is used to enhance the ¹H and ¹³C NMR signals of lactate esters, which find use in a wide range of medical, pharmaceutical, and food science applications. This is achieved by the indirect relay of magnetization from para-hydrogen, a spin isomer of dihydrogen, to OH-containing lactate esters via a SABRE-hyperpolarized NH intermediary. This delivers ¹H and ¹³C NMR signal enhancements as high as 245- and 985-fold, respectively, which makes the lactate esters far more detectable using NMR. DFT-calculated J-couplings and spin dynamics simulations indicate that, while polarization can be transferred from the lactate OH to other ¹H nuclei via the J-coupling network, incoherent mechanisms are needed to polarize the ¹³C nuclei at the 6.5 mT transfer field used. The resulting sensitivity boost is predicted to be of great benefit for the NMR detection and quantification of low concentrations (<mM) of lactate esters and could provide a useful precursor for the production of hyperpolarized lactate, a key metabolite.

Synthesis, Mesomorphism, Photophysics, and Device Properties of Liquid-Crystalline Pincer Complexes of Gold(III) Containing Semiperfluorinated Chains

Gold(III) complexes of C^∧N^∧C-coordinating 2,6-diphenylpyridine pincer ligands with arylacetylide co-ligands are known triplet emitters at room temperature. We have reported previously that by functionalizing both the pincer ligand and the phenylacetylene with alkoxy chains, liquid crystallinity may be induced, with the complexes showing columnar mesophases. We now report new derivatives in which the phenylacetylene incorporates one, two, or three 1H,1H,2H,2H-perfluoroalkyl chains. In terms of intermolecular interactions, solution ¹H NMR experiments suggest that the semiperfluoroalkyl chains promote a parallel, head-to-head arrangement of neighboring molecules relative to one another, rather than the anti-parallel, head-to-tail orientation found for the all-hydrocarbon materials. In terms of the liquid crystal properties, the complexes show columnar phases, with the addition of the more rigid fluorocarbon chains leading to a stabilization of both the crystal and liquid crystal mesophases. Mesophase temperature ranges were also wider. Interestingly, the amphiphilic nature of these complexes is evident through the observation of a frustrated columnar nematic phase between a Col_r and a Col_h phase, an observation recently reported in detail for one compound (Liq. Cryst., 2022, doi: 10.1080/02678292.2021.1991017). While calculation shows that, despite the "electronic insulation" provided by the dimethylene spacer group in the semiperfluoroalkyl chains, a small hypsochromic shift in one component of the absorption band is anticipated, experimentally this effect is not observed in the overall absorption envelope. Complexes with substituents in the 3,3',4,4'-positions of the phenyl rings of the pincer ligand once more show higher-luminescence quantum yields than the analogues with substituents in the 4,4'-positions only, associated with the lower-energy-emissive state in the former. However, in contrast to the observations with all-hydrocarbon analogues, the luminescence quantum yield of the complexes with 3,3',4,4'-substitution on the pincer increases as the number of semiperfluoroalkyl chains on the phenylacetylide increases, from 20% (one chain) to 34% (three chains). External quantum efficiencies in fabricated OLED devices are, however, low, attributed to the poor dispersion in the host materials on account of the fluorinated chains.

A high-resolution single-molecule sequencing-based Arabidopsis transcriptome using novel methods of Iso-seq analysis

BACKGROUND

Accurate and comprehensive annotation of transcript sequences is essential for transcript quantification and differential gene and transcript expression analysis. Single-molecule long-read sequencing technologies provide improved integrity of transcript structures including alternative splicing, and transcription start and polyadenylation sites. However, accuracy is significantly affected by sequencing errors, mRNA degradation, or incomplete cDNA synthesis.

RESULTS

We present a new and comprehensive Arabidopsis thaliana Reference Transcript Dataset 3 (AtRTD3). AtRTD3 contains over 169,000 transcripts-twice that of the best current Arabidopsis transcriptome and including over 1500 novel genes. Seventy-eight percent of transcripts are from Iso-seq with accurately defined splice junctions and transcription start and end sites. We develop novel methods to determine splice junctions and transcription start and end sites accurately. Mismatch profiles around splice junctions provide a powerful feature to distinguish correct splice junctions and remove false splice junctions. Stratified approaches identify high-confidence transcription start and end sites and remove fragmentary transcripts due to degradation. AtRTD3 is a major improvement over existing transcriptomes as demonstrated by analysis of an Arabidopsis cold response RNA-seq time-series. AtRTD3 provides higher resolution of transcript expression profiling and identifies cold-induced differential transcription start and polyadenylation site usage.

CONCLUSIONS

AtRTD3 is the most comprehensive Arabidopsis transcriptome currently. It improves the precision of differential gene and transcript expression, differential alternative splicing, and transcription start/end site usage analysis from RNA-seq data. The novel methods for identifying accurate splice junctions and transcription start/end sites are widely applicable and will improve single-molecule sequencing analysis from any species.

The Measurement Properties and Acceptability of a New Parent–Infant Bonding Tool (‘Me and My Baby’) for Use in United Kingdom Universal Healthcare Settings: A Psychometric, Cross-Sectional Study

Introduction

The National Institute for Health and Care Excellence (NICE) guidelines acknowledge the importance of the parent–infant relationship for child development but highlight the need for further research to establish reliable tools for assessment, particularly for parents of children under 1 year. This study explores the acceptability and psychometric properties of a co-developed tool, ‘Me and My Baby’ (MaMB).

Study design

A cross-sectional design was applied. The MaMB was administered universally (in two sites) with mothers during routine 6–8-week Health Visitor contacts. The sample comprised 467 mothers (434 MaMB completers and 33 ‘non-completers’). Dimensionality of instrument responses were evaluated via exploratory and confirmatory ordinal factor analyses. Item response modeling was conducted via a Rasch calibration to evaluate how the tool conformed to principles of ‘fundamental measurement’. Tool acceptability was evaluated via completion rates and comparing ‘completers’ and ‘non-completers’ demographic differences on age, parity, ethnicity, and English as an additional language. Free-text comments were summarized. Data sharing agreements and data management were compliant with the General Data Protection Regulation, and University of York data management policies.

Results

High completion rates suggested the MaMB was acceptable. Psychometric analyses showed the response data to be an excellent fit to a unidimensional confirmatory factor analytic model. All items loaded statistically significantly and substantially (>0.4) on a single underlying factor (latent variable). The item response modeling showed that most MaMB items fitted the Rasch model. (Rasch) item reliability was high (0.94) yet the test yielded little information on each respondent, as highlighted by the relatively low ‘person separation index’ of 0.1.

Conclusion and next steps

MaMB reliably measures a single construct, likely to be infant bonding. However, further validation work is needed, preferably with ‘enriched population samples’ to include higher-need/risk families. The MaMB tool may benefit from reduced response categories (from four to three) and some modest item wording amendments. Following further validation and reliability appraisal the MaMB may ultimately be used with fathers/other primary caregivers and be potentially useful in research, universal health settings as part of a referral pathway, and clinical practice, to identify dyads in need of additional support/interventions.

Steric and electronic effects on the 1 H hyperpolarisation of substituted pyridazines by signal amplification by reversible exchange

Utility of the pyridazine motif is growing in popularity as pharmaceutical and agrochemical agents. The detection and structural characterisation of such materials is therefore imperative for the successful development of new products. Signal amplification by reversible exchange (SABRE) offers a route to dramatically improve the sensitivity of magnetic resonance methods, and we apply it here to the rapid and cost-effective hyperpolarisation of substituted pyridazines. The 33 substrates investigated cover a range of steric and electronic properties and their capacity to perform highly effective SABRE is assessed. We find the method to be tolerant to a broad range of electron donating and withdrawing groups; however, good sensitivity is evident when steric bulk is added to the 3- and 6-positions of the pyridazine ring. We optimise the method by reference to a disubstituted ester that yields signal gains of >9000-fold at 9.4 T (>28% spin polarisation).

Radical-anion coupling through reagent design: hydroxylation of aryl halides

The design and development of an oxime-based hydroxylation reagent, which can chemoselectively convert aryl halides (X = F, Cl, Br, I) into phenols under operationally simple, transition-metal-free conditions is described. Key to the success of this approach was the identification of a reducing oxime anion which can interact and couple with open-shell aryl radicals. Experimental and computational studies support the proposed radical-nucleophilic substitution chain mechanism.

Artificial intelligence explainability: the technical and ethical dimensions

In recent years, several new technical methods have been developed to make AI-models more transparent and interpretable. These techniques are often referred to collectively as 'AI explainability' or 'XAI' methods. This paper presents an overview of XAI methods, and links them to stakeholder purposes for seeking an explanation. Because the underlying stakeholder purposes are broadly ethical in nature, we see this analysis as a contribution towards bringing together the technical and ethical dimensions of XAI. We emphasize that use of XAI methods must be linked to explanations of human decisions made during the development life cycle. Situated within that wider accountability framework, our analysis may offer a helpful starting point for designers, safety engineers, service providers and regulators who need to make practical judgements about which XAI methods to employ or to require. This article is part of the theme issue 'Towards symbiotic autonomous systems'.

Human leishmaniasis vaccines: Use cases, target population and potential global demand

The development of vaccines against one or all forms of human leishmaniasis remains hampered by a paucity of investment, at least in part resulting from the lack of well-evidenced and agreed estimates of vaccine demand. Starting from the definition of 4 main use cases (prevention of visceral leishmaniasis, prevention of cutaneous leishmaniasis, prevention of post-kala-azar dermal leishmaniasis and treatment of post-kala-azar dermal leishmaniasis), we have estimated the size of each target population, focusing on those endemic countries where incidence levels are sufficiently high to justify decisions to adopt a vaccine. We assumed a dual vaccine delivery strategy, including a wide age-range catch-up campaign before the start of routine immunisation. Vaccine characteristics and delivery parameters reflective of a target product profile and the likely duration of the clinical development effort were considered in forecasting the demand for each of the four indications. Over a period of 10 years, this demand is forecasted to range from 300-830 million doses for a vaccine preventing visceral leishmaniasis and 557-1400 million doses for a vaccine preventing cutaneous leishmaniasis under the different scenarios we simulated. In a scenario with an effective prophylactic visceral leishmaniasis vaccine, demand for use to prevent or treat post-kala-azar dermal leishmaniasis would be more limited (over the 10 years ~160,000 doses for prevention and ~7,000 doses for treatment). Demand would rise to exceed 330,000 doses, however, in the absence of an effective vaccine for visceral leishmaniasis. Because of the sizeable demand and potential for public health impact, a single-indication prophylactic vaccine for visceral or cutaneous leishmaniasis, and even more so a cross-protective prophylactic vaccine could attract the interest of commercial developers. Continuous refinement of these first-of-their kind estimates and confirmation of country willingness and ability to pay will be paramount to inform the decisions of policy makers and developers in relation to a leishmaniasis vaccine. Positive decisions can provide a much-needed contribution towards the achievement of global leishmaniasis control.

Enzyme-catalyzed synthesis of malonate polyesters and their use as metal chelating materials

Following the environmental problems caused by non-degradable plastics there is a need to synthesise greener and more sustainable polymers. In this work we describe, for the first time, the facile enzyme-catalysed synthesis of linear polyesters using dimethyl malonate as the diester. These polymers, containing a different aliphatic diol component (C4, C6 or C8), were synthesised in solventless conditions using immobilized Candida antarctica lipase B as the biocatalyst. The potential of enzymes for catalysing this reaction is compared with the unsuccessful antimony- and titanium-catalysed synthesis (T > 150 °C). The application of the synthesized polymers as effective metal chelators in biphasic, green solvent systems was also described, together with the characterisation of the synthesised materials.

Conflict violence reduction and pregnancy outcomes: A regression discontinuity design in Colombia

BACKGROUND

The relationship between exposure to conflict violence during pregnancy and the risks of miscarriage, stillbirth, and perinatal mortality has not been studied empirically using rigorous methods and appropriate data. We investigated the association between reduced exposure to conflict violence during pregnancy and the risks of adverse pregnancy outcomes in Colombia.

METHODS AND FINDINGS

We adopted a regression discontinuity (RD) design using the July 20, 2015 cease-fire declared during the Colombian peace process as an exogenous discontinuous change in exposure to conflict events during pregnancy, comparing women with conception dates before and after the cease-fire date. We constructed the cohorts of all pregnant women in Colombia for each day between January 1, 2013 and December 31, 2017 using birth and death certificates. A total of 3,254,696 women were followed until the end of pregnancy. We measured conflict exposure as the total number of conflict events that occurred in the municipality where a pregnant woman lived during her pregnancy. We first assessed whether the cease-fire did induce a discontinuous fall in conflict exposure for women with conception dates after the cease-fire to then estimate the association of this reduced exposure with the risks of miscarriage, stillbirth, and perinatal mortality. We found that the July 20, 2015 cease-fire was associated with a reduction of the average number of conflict events (from 2.64 to 2.40) to which women were exposed during pregnancy in their municipalities of residence (mean differences -0.24; 95% confidence interval [CI] -0.35 to -0.13; p < 0.001). This association was greater in municipalities where Fuerzas Armadas Revolucionarias de Colombia (FARC) had a greater presence historically. The reduction in average exposure to conflict violence was, in turn, associated with a decrease of 9.53 stillbirths per 1,000 pregnancies (95% CI -16.13 to -2.93; p = 0.005) for municipalities with total number of FARC-related violent events above the 90th percentile of the distribution of FARC-related conflict events and a decrease of 7.57 stillbirths per 1,000 pregnancies (95% CI -13.14 to -2.00; p = 0.01) for municipalities with total number of FARC-related violent events above the 75th percentile of FARC-related events. For perinatal mortality, we found associated reductions of 10.69 (95% CI -18.32 to -3.05; p = 0.01) and 6.86 (95% CI -13.24 to -0.48; p = 0.04) deaths per 1,000 pregnancies for the 2 types of municipalities, respectively. We found no association with miscarriages. Formal tests support the validity of the key RD assumptions in our data, while a battery of sensitivity analyses and falsification tests confirm the robustness of our empirical results. The main limitations of the study are the retrospective nature of the information sources and the potential for conflict exposure misclassification.

CONCLUSIONS

Our study offers evidence that reduced exposure to conflict violence during pregnancy is associated with important (previously unmeasured) benefits in terms of reducing the risk of stillbirth and perinatal deaths. The findings are consistent with such beneficial associations manifesting themselves mainly through reduced violence exposure during the early stages of pregnancy. Beyond the relevance of this evidence for other countries beset by chronic armed conflicts, our results suggest that the fledgling Colombian peace process may be already contributing to better population health.

Tobacco Smoking and Associated Factors Among People Living With HIV in Uganda

INTRODUCTION

The prevalence of smoking among people living with HIV (PLWH) in Uganda is high.

AIMS AND METHODS

We assessed the smoking patterns, behaviors, and associated factors among PLWH in Uganda through a cross-sectional survey. Descriptive statistics were used to describe smoking patterns and behaviors. Logistic regression was used to identify factors associated with current smoking status.

RESULTS

We recruited 777 participants between October and November 2019: 387 (49.8%) current smokers and 390 (50.2%) nonsmokers. 60.9% were males, and the mean age was 40.5 (SD 10.7) years. In multivariate logistic regression, the following increased the odds of being a current smoker: being male (odds ratio [OR] 6.60 [95% confidence interval, CI = 4.34-10.04]), having at least two smokers among five closest friends (OR 3.97 [95% CI = 2.08-7.59]), living in smoking-permitted households (OR 5.83 [95% CI = 3.32-10.23]), alcohol use (OR 3.96 [95% CI = 2.34-6.71]), a higher perceived stress score (OR 2.23 [95% CI = 1.50-3.34]), and higher health-related quality of life (OR 5.25 [95% CI = 1.18-23.35]). Among smokers, the mean Fagerström Test for Nicotine Dependence score was 3.0 (SD 1.9), and 52.5% were making plans to quit. Self-efficacy to resist smoking and knowledge of the impact of smoking on PLWH's health were low.

CONCLUSIONS

Being male, having at least two smokers among five closest friends, living in smoking-permitted households, alcohol use, higher perceived stress scores, and higher health-related quality of life were associated with being a current smoker. Smokers had low to moderate nicotine dependence, high willingness to quit, and low self-efficacy.

IMPLICATIONS

Future behavioral smoking cessation interventions for PLWH should address co-consumption with alcohol and comorbid mental health conditions that are common among PLWH such as stress. In addition, they should take into account the lack of knowledge among this population of the impact of smoking on their health, and low self-efficacy. Given the relatively low levels of nicotine dependency and high levels of willingness to quit in our sample, smoking cessation interventions, if offered, are likely to support this population in achieving long-term smoking abstinence.

Critical STEM Literacy and the COVID-19 Pandemic

The COVID-19 pandemic has resulted in unprecedented amounts of information communicated to the public relating to STEM. The pandemic can be seen as a 'wicked problem' defined by high complexity, uncertainty and contested social values requiring a transdisciplinary approach formulating social policy. This article argues that a 'Critical STEM Literacy' is required to engage sufficiently with STEM knowledge and how science operates and informs personal health decisions. STEM literacy is necessary to critique government social policy decisions that set rules for behaviour to limit the spread of COVID-19. Ideas of scientific, mathematical and critical literacy are discussed before reviewing some current knowledge of the SARS-CoV-2 virus to aid interpretation of the examples provided. The article draws on experience of the pandemic in the United Kingdom (UK), particularly mathematical modelling used to calculate the reproductive rate (R) of COVID-19, communication of mortality and case data using graphs and the mitigation strategies of social distancing and mask wearing. In all these examples, there is an interaction of STEM with a political milieu that often misrepresents science as activity to generate one dependable truth, rather than through careful empirical validation of new knowledge. Critical STEM literacy thus requires appreciation of the social practices of science such as peer review and assessment of bias. Implications of the pandemic for STEM education in schools requiring critical thinking and in understanding disease epidemiology in a global context are discussed.

The importance of transdiagnostic symptom level assessment to understanding prognosis for depressed adults: analysis of data from six randomised control trials

BACKGROUND

Depression is commonly perceived as a single underlying disease with a number of potential treatment options. However, patients with major depression differ dramatically in their symptom presentation and comorbidities, e.g. with anxiety disorders. There are also large variations in treatment outcomes and associations of some anxiety comorbidities with poorer prognoses, but limited understanding as to why, and little information to inform the clinical management of depression. There is a need to improve our understanding of depression, incorporating anxiety comorbidity, and consider the association of a wide range of symptoms with treatment outcomes.

METHOD

Individual patient data from six RCTs of depressed patients (total n = 2858) were used to estimate the differential impact symptoms have on outcomes at three post intervention time points using individual items and sum scores. Symptom networks (graphical Gaussian model) were estimated to explore the functional relations among symptoms of depression and anxiety and compare networks for treatment remitters and those with persistent symptoms to identify potential prognostic indicators.

RESULTS

Item-level prediction performed similarly to sum scores when predicting outcomes at 3 to 4 months and 6 to 8 months, but outperformed sum scores for 9 to 12 months. Pessimism emerged as the most important predictive symptom (relative to all other symptoms), across these time points. In the network structure at study entry, symptoms clustered into physical symptoms, cognitive symptoms, and anxiety symptoms. Sadness, pessimism, and indecision acted as bridges between communities, with sadness and failure/worthlessness being the most central (i.e. interconnected) symptoms. Connectivity of networks at study entry did not differ for future remitters vs. those with persistent symptoms.

CONCLUSION

The relative importance of specific symptoms in association with outcomes and the interactions within the network highlight the value of transdiagnostic assessment and formulation of symptoms to both treatment and prognosis. We discuss the potential for complementary statistical approaches to improve our understanding of psychopathology.

Transforming urban planning processes and outcomes through creative methods

Inclusively delivering the sustainable development goals (SDGs) remains challenging, particularly in urban areas, where some of the most pressing concerns exist. To achieve the transformative SDG agenda, new methods are required to overcome current deficits in engagement around inclusion and equitable outcomes. Evaluating against theories of governance and inclusion, we test a mixture of digital and physical creative methods abilities to deliver co-designed solutions that influence mobility and road safety planning outcomes in East African cities. Greater inclusion led to improved interactions of citizens with decision makers, and the identification of novel, practical solutions, delivering some elements of transformation. Risks include creative methods being used to co-opt communities to official agendas, and institutional planning norms needing to adapt to respond to a wider range of stakeholders. Overall, where risks are mitigated, we recommend that using Creative Methods could localise SDG delivery, ensuring more equitable and effective outcomes from infrastructure development investments.

Hyperpolarisation of weakly binding N-heterocycles using signal amplification by reversible exchange

Signal Amplification by Reversible Exchange (SABRE) is a catalytic method for improving the detection of molecules by magnetic resonance spectroscopy. It achieves this by simultaneously binding the target substrate (sub) and para-hydrogen to a metal centre. To date, sterically large substrates are relatively inaccessible to SABRE due to their weak binding leading to catalyst destabilisation. We overcome this problem here through a simple co-ligand strategy that allows the hyperpolarisation of a range of weakly binding and sterically encumbered N-heterocycles. The resulting 1H NMR signal size is increased by up to 1400 times relative to their more usual Boltzmann controlled levels at 400 MHz. Hence, a significant reduction in scan time is achieved. The SABRE catalyst in these systems takes the form [IrX(H)2(NHC)(sulfoxide)(sub)] where X = Cl, Br or I. These complexes are shown to undergo very rapid ligand exchange and lower temperatures dramatically improve the efficiency of these SABRE catalysts.

Generative models of network dynamics provide insight into the effects of trade on endemic livestock disease

We develop and apply analytically tractable generative models of livestock movements at national scale. These go beyond current models through mechanistic modelling of heterogeneous trade partnership network dynamics and the trade events that occur on them. Linking resulting animal movements to disease transmission between farms yields analytical expressions for the basic reproduction number R ₀. We show how these novel modelling tools enable systems approaches to disease control, using R ₀ to explore impacts of changes in trading practices on between-farm prevalence levels. Using the Scottish cattle trade network as a case study, we show our approach captures critical complexities of real-world trade networks at the national scale for a broad range of endemic diseases. Changes in trading patterns that minimize disruption to business by maintaining in-flow of animals for each individual farm reduce R ₀, with the largest reductions for diseases that are most challenging to eradicate. Incentivizing high-risk farms to adopt such changes exploits 'scale-free' properties of the system and is likely to be particularly effective in reducing national livestock disease burden and incursion risk. Encouragingly, gains made by such targeted modification of trade practices scale much more favourably than comparably targeted improvements to more commonly adopted farm-level biosecurity.

Teaching Professionalism to Medical Students Using Dissection-Based Anatomy Education: a Practical Guide

Professionalism is a core competency for all healthcare professionals and is a subject of great interest within the academic community due to its vital importance in delivering the highest quality patient care. Despite this, professionalism remains difficult to define, teach and assess. The potential use of anatomy education in teaching professionalism has been increasingly highlighted within the literature, but still remains an underutilised tool in medical education. Therefore, this practical guide offers evidence-based practical points for successfully incorporating professionalism within a dissection-based anatomy course delivered to undergraduate medical students.

A Rapid Review of Prescribing Education Interventions

INTRODUCTION

Many studies conducted on the causes and nature of prescribing errors have highlighted the inadequacy of teaching and training of prescribers. Subsequently, a rapid review was undertaken to update on the nature and effectiveness of educational interventions aimed at improving the prescribing skills and competencies.

METHODS

Twenty-two studies taking place between 2009 and 2019 were identified across nine databases.

RESULTS AND DISCUSSION

This review reinforced the importance of the WHO Guide to Good Prescribing to prescribing curriculum design as well as the effectiveness of small group teaching. However, it also highlighted the lack of innovation in prescribing education and lack of longitudinal follow-up regarding the effectiveness of prescribing education interventions.

Further insights into the operation of the Chinese number system: Competing effects of Arabic and Mandarin number formats

Here we report the results of a speeded relative quantity task with Chinese participants. On each trial a single numeral (the probe) was presented and the instructions were to respond as to whether it signified a quantity less than or greater than five (the standard). In separate blocks of trials, the numerals were presented either in Mandarin or in Arabic number formats. In addition to the standard influence of numerical distance, a significant predictor of performance was the degree of physical similarity between the probe and the standard as depicted in Mandarin. Additionally, competing effects of physical similarity, defined in terms of the Arabic number format, were also found. Critically the size of these different effects of physical similarity varied systematically across individuals such that larger effects of one compensated for smaller effects of the other. It is argued that the data favor accounts of processing that assume that different number formats access different format-specific representations of quantities. Moreover, for Chinese participants the default is to translate numerals into a Mandarin format prior to accessing quantity information. The efficacy of this translation process is itself influenced by a competing tendency to carry out a translation into Arabic format.

Machine learning discriminates a movement disorder in a zebrafish model of Parkinson's disease

Animal models of human disease provide an in vivo system that can reveal molecular mechanisms by which mutations cause pathology, and, moreover, have the potential to provide a valuable tool for drug development. Here, we have developed a zebrafish model of Parkinson's disease (PD) together with a novel method to screen for movement disorders in adult fish, pioneering a more efficient drug-testing route. Mutation of the PARK7 gene (which encodes DJ-1) is known to cause monogenic autosomal recessive PD in humans, and, using CRISPR/Cas9 gene editing, we generated a Dj-1 loss-of-function zebrafish with molecular hallmarks of PD. To establish whether there is a human-relevant parkinsonian phenotype in our model, we adapted proven tools used to diagnose PD in clinics and developed a novel and unbiased computational method to classify movement disorders in adult zebrafish. Using high-resolution video capture and machine learning, we extracted novel features of movement from continuous data streams and used an evolutionary algorithm to classify parkinsonian fish. This method will be widely applicable for assessing zebrafish models of human motor diseases and provide a valuable asset for the therapeutics pipeline. In addition, interrogation of RNA-seq data indicate metabolic reprogramming of brains in the absence of Dj-1, adding to growing evidence that disruption of bioenergetics is a key feature of neurodegeneration.This article has an associated First Person interview with the first author of the paper.

Exploring the Hidden Curriculum's Impact on Medical Students: Professionalism, Identity Formation and the Need for Transparency

The hidden curriculum within medical education has been a topic of recent debate. Consensus opinion regarding the continued relevance of this term, what constitutes the hidden curriculum, and the nature of its impact do not exist. Further research is required to contribute to this debate. This work sets out to investigate which factors beyond taught cognitive knowledge influence medical students in clinical and educational environments and examine how this occurs. Semi-structured focus group interviews were conducted with 39 students from one UK medical school. Fourteen faculty were interviewed individually to triangulate data. Data were analysed using constructivist thematic analysis, informed by grounded theory convention. The presence of the hidden curriculum was clearly demonstrated, acting through role modelling, organizational culture, stereotyping and professional dress. Mentioned frequently were the influences of the hidden curriculum on student professionalism and identity development. Professionalism was perceived as being negatively impacted by the hidden curriculum and seen as an imposition from senior faculty to control students. Students believe medical identity formation begins prior to medical school, in a process known as "anticipatory socialization", a previously unstudied identity transition. Students felt covert institutional agendas negatively impacted their identity, pushing them further from the identity their institution was encouraging them to acquire. Key messages for educators include the need to explore the hidden curriculum through discussion with students. Improving transparency of organizational culture may allow students to interpret institutional agendas in the way institutions formally intend, reducing orthogonal interpretations of organizational culture and subsequent impact upon identity formation.

Air care: an 'aerography' of breath, buildings and bugs in the cystic fibrosis clinic

With significant relevance to the Covid-19 pandemic, this paper contributes to emerging 'aerographic' research on the socio-materialities of air and breath, based on an in-depth empirical study of three hospital-based lung infection clinics treating people with cystic fibrosis. We begin by outlining the changing place of atmosphere in hospital design from the pre-antibiotic period and into the present. We then turn to the first of three aerographic themes where air becomes a matter of grasping and visualising otherwise invisible airborne infections. This includes imagining patients located within bodily spheres or 'cloud bodies', conceptually anchored in Irigaray's thoughts on the 'forgetting of the air' and Sloterdijk's immunitary 'spherology' of the body. Our second theme explores the material politics of air, air conditioning, window design and the way competing 'air regimes' come into conflict with each other at the interface of buildings, bodies and the biotic. Our final theme attends to the 'cost of air', the aero-economic problem of atmospheric scarcity within modern high-rise, deep-density healthcare architectures.

'I'm sorry to hear that'-Empathy and Empathic Dissonance: the Perspectives of PA Students

CONTEXT

Our understanding of clinical empathy could be enhanced through qualitative research-research currently under-represented in the field. Physician associates within the UK undergo an intensive 2-year postgraduate medical education. As a new group of health professionals, they represent a fresh pair of eyes through which to examine clinical empathy, its nature and teaching.

METHODS

Working with a constructivist paradigm, utilising grounded theory methodology, researchers studied 19 purposively sampled physician associate students in two UK medical schools. One-to-one semi-structured interviews were transcribed verbatim. Data were analysed using a grounded theory approach.

RESULTS

The global themes were the pathways to empathy, empathy modifiers and empathic dissonance a novel term to describe the discomfort students experience when pressurised into making empathic statements they don't sincerely feel. Students preferred using non-verbal over verbal expressions of empathy. A conceptual model is proposed. The more substantial empathic pathway, affective empathy, involves input from the heart. An alternative empathy, more constrained, comes from the head: cognitive empathy was considered a solution to time pressure and emotional burden. Formal teaching establishes empathic dissonance, a problem which stems from over-reliance on the empathic statement as the means to deliver clinical empathy.

CONCLUSIONS

This study furthers our understanding of the construct and teaching of empathy. It identifies empathic barriers, especially time pressure. It proposes a novel concept-empathic dissonance-a concept that challenges medical educationalists to reframe future empathy teaching.

Acoustic-phonetic and auditory mechanisms of adaptation in the perception of sibilant fricatives

Listeners are highly proficient at adapting to contextual variation when perceiving speech. In the present study, we examined the effects of brief speech and nonspeech contexts on the perception of sibilant fricatives. We explored three theoretically motivated accounts of contextual adaptation, based on phonetic cue calibration, phonetic covariation, and auditory contrast. Under the cue calibration account, listeners adapt by estimating a talker-specific average for each phonetic cue or dimension; under the cue covariation account, listeners adapt by exploiting consistencies in how the realization of speech sounds varies across talkers; under the auditory contrast account, adaptation results from (partial) masking of spectral components that are shared by adjacent stimuli. The spectral center of gravity, a phonetic cue to fricative identity, was manipulated for several types of context sound: /z/-initial syllables, /v/-initial syllables, and white noise matched in long-term average spectrum (LTAS) to the /z/-initial stimuli. Listeners' perception of the /s/-/ʃ/ contrast was significantly influenced by /z/-initial syllables and LTAS-matched white noise stimuli, but not by /v/-initial syllables. No significant difference in adaptation was observed between exposure to /z/-initial syllables and matched white noise stimuli, and speech did not have a considerable advantage over noise when the two were presented consecutively within a context. The pattern of findings is most consistent with the auditory contrast account of short-term perceptual adaptation. The cue covariation account makes accurate predictions for speech contexts, but not for nonspeech contexts or for the absence of a speech-versus-nonspeech difference.

A Medical Science Educator's Guide to Selecting a Research Paradigm: Building a Basis for Better Research

A research paradigm, or set of common beliefs about research, should be a key facet of any research project. However, despite its importance, there is a paucity of general understanding in the medical sciences education community regarding what a research paradigm consists of and how to best construct one. With the move within medical sciences education towards greater methodological rigor, it is now more important than ever for all educators to understand simply how to better approach their research via paradigms. In this monograph, a simplified approach to selecting an appropriate research paradigm is outlined. Suggestions are based on broad literature, medical education sources, and the author's own experiences in solidifying and communicating their research paradigms. By assisting in detailing the philosophical underpinnings of individuals research approaches, this guide aims to help all researchers improve the rigor of their projects and improve upon overall understanding in research communication.

Uncovering Hidden Curricula: Use of Dark Humor in Anatomy Labs and its Implications for Basic Sciences Education

Humor is subjective within most settings, but within the anatomy laboratory, it is likely to be significantly more contentious. While humor may be considered a component of the hidden curriculum of medical education, it has yet to be studied specifically from a basic sciences perspective. This study sought to understand if, when, how, and why humor may be used in anatomy labs and the implications this may have in basic sciences education. A survey consisting of demographic and qualitative items was designed to sample widely from academics, students, and health professionals with anatomy laboratory experience. A total of 185 respondents, representing 9 countries participated following purposive sampling and snowball recruitment. Findings of significance were 72% of respondents who had experienced dark humor within the anatomy lab. Themes identified from free-text pertained to the use of internal and external barometers to ascertain the appropriateness of humorous remarks and the use of humor as a mechanism for diffusing stress. Polarity in responses concerning the acceptability of dark humor and rude mnemonics was also observed. This study highlighted that while dark humor may be a perceived tension release, many individuals make use of very specific internalized gauges to determine when and what humor may be appropriate. The data emphasized the need for not only future humanistic-focused anatomy but also basic sciences, education research, to better understand and have ideal educational experiences for all. Finally, this study provided further evidence of the impact of the hidden curriculum associated with the use of humor within educational and professional settings.

Attention and binding in visual working memory: Two forms of attention and two kinds of buffer storage

We review our research on the episodic buffer in the multicomponent model of working memory (Baddeley, 2000), making explicit the influence of Anne Treisman's work on the way our research has developed. The crucial linking theme concerns binding, whereby the individual features of an episode are combined as integrated representations. We summarize a series of experiments on visual working memory that investigated the retention of feature bindings and individual features. The effects of cognitive load, perceptual distraction, prioritization, serial position, and their interactions form a coherent pattern. We interpret our findings as demonstrating contrasting roles of externally driven and internally driven attentional processes, as well as a distinction between visual buffer storage and the focus of attention. Our account has strong links with Treisman's concept of focused attention and aligns with a number of contemporary approaches to visual working memory.

Factors Affecting the Growth of Pseudokirchneriella subcapitata in Single-Species Tests: Lessons for the Experimental Design and the Reproducibility of a Multitrophic Laboratory Microcosm

The need for an integrated risk assessment at an ecologically relevant scale (e.g., at the population/community levels) has been acknowledged. Multispecies systems with increased ecological complexity, however, are difficult if not impossible to reproduce. The laboratory-scale microcosm TriCosm (Pseudokirchneriella subcapitata, Ceriodaphnia dubia, Hydra viridissima) of intermediate complexity was developed for the reproducible assessment of chemical effects at the population/community levels. The system dynamics were repeatable in the short term, but interexperimental variation of algal dynamics in the long term triggered knock-on effects on grazer and predator populations. We present 20 experiments to assess the effects of 12 factors (test medium, vessel type/condition, shaking speed, light intensity/regime, inoculation density, medium preparation components, metal concentration/composition, buffering salt type/concentration) on algal growth in the TriCosm enclosure. Growth rates varied between ≤ 0 and 1.40 (± 0.21) and generally were greatest with increased shaking speed, light exposure, medium buffer, or aeration time. Treatments conducted in dishes with aseptically prepared, lightly buffered, and/or hardly aerated medium resulted in low growth rates. We found that inter-experimental variation of algal dynamics in the TriCosm was caused by a modification of medium preparation (omission of medium aeration) with the aim of reducing microbial contamination. Our findings highlight the facts that consistency in experimental procedures and in-depth understanding of system components are indispensable to achieve repeatability. Environ Toxicol Chem 2019;00:1-13. © 2019 SETAC.