Axially-chiral boramidine for detailed (chir)optical studies

The inclusion of boron atoms into chiral π-conjugated systems is an effective strategy to unlock unique chiroptical properties. Herein, the preparation and characterization of a configurationally stable axially-chiral boramidine are reported, showcasing absorption in the UV domain, deep-blue fluorescence (Φ up to 94%), and ca. |10-3| gabs and glum values. Detailed photophysical studies and quantum-chemical calculations clearly elucidate the deactivation pathways of the emissive state to triplet excited states, involving increased spin-orbit coupling between the lowest singlet excited state and an upper triplet state.

COVID-19 vaccine coverage, determinants and inequity amongst refugees and migrants in Pakistan: a cross-sectional study

OBJECTIVE

Migrants and refugees are at a disadvantage in accessing basic necessities. The objective of this study is to assess the inequity in access, needs and determinants of COVID-19 vaccination among refugees and migrant populations in Pakistan.

DESIGN

We conducted a mixed-method study comprising a cross-sectional survey and a qualitative study. In this paper, we will only report the findings from the cross-sectional survey.

SETTING

This survey was conducted in different cities of Pakistan including Quetta, Karachi and Hyderabad.

PARTICIPANTS

A total of 570 participants were surveyed including refugees and migrants, both in regular and irregular situations.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome of the study was to estimate the proportion of refugees and migrants, both in regular and irregular situations vaccinated against COVID-19 and assess the inequity. The χ2 test and Fisher's exact test were used to determine the significant differences in proportions between refugees and migrants and between regions.

RESULTS

The survey showed that only 26.9% of the refugee and migrant population were tested for COVID-19, 4.56% contracted coronavirus, and 3.85% were hospitalised due to COVID-19. About 66% of the refugees and migrants were fully vaccinated including those who received the single-dose vaccine or received all two doses, and 17.6% were partially vaccinated. Despite vaccination campaigns by the government, 14.4% of the refugee and migrant population remained unvaccinated mostly because of vaccines not being offered, distant vaccination sites, limited access, unavailability of COVID-19 vaccine or due to a difficult registration process. Vaccination rates varied across provinces, genders and migrant populations due to misconceptions, and several social, cultural and geographical barriers.

CONCLUSION

This study highlights the COVID-19 vaccine coverage, access and inequity faced by refugees and migrants during the pandemic. It suggests early prioritisation of policies inclusive of all refugees and migrants and the provision of identification documents to ease access to basic necessities.

Modulation of the northward penetration of Antarctica intermediate waters into the eastern equatorial Indian Ocean under glacial and interglacial conditions

The Indo-Pacific warm pool is the warmest and most dynamic ocean-atmosphere-climate system on Earth and was subject to significant climate changes during the Pleistocene glacial-interglacial transitions. This has been shown to significantly affected the strength of surface waters that redistribute heat from the tropics to the southern part of the Indian Ocean. Here we investigate the response of the oceanic circulation at intermediate depth (1200 m) of the eastern equatorial Indian Ocean (EEIO) with neodymium (Nd) isotopes in the context of the climatic oscillation of the last 500 ka. The most striking feature of our new dataset is the seesaw Nd record that mimics glacial-interglacial cycles. While the interglacial periods are characterized by a higher contribution of the less radiogenic neodymium (~ - 7εNd) Antarctic Intermediate Water (AAIW), the glacial periods are characterized by more radiogenic water mass of Pacific origin (~ - 5εNd). To explain the increase in the εNd signature toward a more radiogenic signature as the Indo-Pacific connection is reduced under the low sea level of the glacial periods, we show that under global cooling, the AAIW advances northward into the tropics, which is a consequence of the general slowdown of the thermohaline circulation. Therefore, oceanic mixing at intermediate depth in the eastern tropical Indian intermediate water is modulated by the production rate of the AAIW in the Southern Ocean. Our study provides new evidence for the role that changes in the deep oceanic conditions play in amplifying externally forced climate changes that ultimately lead to drier/moister atmospheric conditions and weaker/stronger monsoons during glacial/interglacial periods over eastern tropical Indian Ocean.

Pfeiffer effect on configurationally labile dyes within ternary complexes with metal ions and enantiopure macrocycles

A configurationally-labile helical dye, 2,4,5,7-tetranitrofluorenone oximate, is used to probe complexes made of enantiopure macrocycles and mono/divalent metal ions. Induced electronic circular dichroism (ECD) and 1H NMR responses are amplified at room temperature only in the presence of K+ and Na+ ions despite larger binding efficiency with alkaline earth metal ions.

UV RESISTANCE LOCUS 8-Mediated UV-B Response Is Required Alongside CRYPTOCHROME 1 for Plant Survival in Sunlight under Field Conditions

As sessile, photoautotrophic organisms, plants are subjected to fluctuating sunlight that includes potentially detrimental ultraviolet-B (UV-B) radiation. Experiments under controlled conditions have shown that the UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8) controls acclimation and tolerance to UV-B in Arabidopsis thaliana; however, its long-term impact on plant fitness under naturally fluctuating environments remain poorly understood. Here, we quantified the survival and reproduction of different Arabidopsis mutant genotypes under diverse field and laboratory conditions. We found that uvr8 mutants produced more fruits than wild type when grown in growth chambers under artificial low-UV-B conditions but not under natural field conditions, indicating a fitness cost in the absence of UV-B stress. Importantly, independent double mutants of UVR8 and the blue light photoreceptor gene CRYPTOCHROME 1 (CRY1) in two genetic backgrounds showed a drastic reduction in fitness in the field. Experiments with UV-B attenuation in the field and with supplemental UV-B in growth chambers demonstrated that UV-B caused the cry1 uvr8 conditional lethal phenotype. Using RNA-seq data of field-grown single and double mutants, we explicitly identified genes showing significant statistical interaction of UVR8 and CRY1 mutations in the presence of UV-B in the field. They were enriched in Gene Ontology categories related to oxidative stress, photoprotection and DNA damage repair in addition to UV-B response. Our study demonstrates the functional importance of the UVR8-mediated response across life stages in natura, which is partially redundant with that of cry1. Moreover, these data provide an integral picture of gene expression associated with plant responses under field conditions.

Anchoring of Metal Complexes on Au25 Nanocluster for Enhanced Photocoupled Electrocatalytic CO2 Reduction

Atomically precise Au nanoclusters (NCs) with discrete energy levels can be used as photosensitizers for CO2 reduction. However, tight ligand capping of Au NCs hinders CO2 adsorption on its active sites. Here, a new hybrid material is obtained by anchoring of thiol functionalized terpyridine metal complexes (metal=Ru, Ni, Fe, Co) on Au NCs by ligand exchange reactions (LERs). The anchoring of Ru and Ni complexes on Au25 NC (Au25 -Ru and Au25 -Ni) leads to adequate CO2 to CO conversion for photocoupled electrocatalytic CO2 reduction (PECR) in terms of high selectivity, with Faradaic efficiency of CO (FECO ) exceeding 90 % in a wide potential range, remarkable activity (CO production rate up to two times higher than that for pristine Au25 PET18 ) and extremely large turnover frequencies (TOFs, 63012 h-1 at -0.97 V for Au25 -Ru and 69989 h-1 at -1.07 V vs. RHE for Au25 -Ni). Moreover, PECR stability test indicates the excellent long-term stability of the modified NCs in contrast with pristine Au NCs. The present approach offers a novel strategy to enhance PECR activity and selectivity, as well as to improve the stability of Au NCs under light illumination, which paves the way for highly active and stable Au NCs catalysts.

Anion-π catalysis on carbon allotropes

Anion-π catalysis, introduced in 2013, stands for the stabilization of anionic transition states on π-acidic aromatic surfaces. Anion-π catalysis on carbon allotropes is particularly attractive because high polarizability promises access to really strong anion-π interactions. With these expectations, anion-π catalysis on fullerenes has been introduced in 2017, followed by carbon nanotubes in 2019. Consistent with expectations from theory, anion-π catalysis on carbon allotropes generally increases with polarizability. Realized examples reach from enolate addition chemistry to asymmetric Diels-Alder reactions and autocatalytic ether cyclizations. Currently, anion-π catalysis on carbon allotropes gains momentum because the combination with electric-field-assisted catalysis promises transformative impact on organic synthesis.

2,4,5,7-Tetranitrofluorenone Oximate for the Naked-Eye Detection of H-Bond Donors and the Chiroptical Sensing of Enantiopure Reagents

Hydrogen bonding greatly influences rates and equilibrium positions of chemical reactions, conformations, and sometimes even stereochemistry. This study reports on tetranitrofluorenone oximate, a novel dye capable of naked-eye detection of hydrogen-bond donating species (HBDs) and of rapid determination of H-bond donation strength by hypsochromic shift monitoring. In addition, the molecule possesses atropisomeric conformations, of M and P configuration, as evidenced in solid and solution state studies by X-ray diffraction and electronic circular dichroism (ECD), respectively. In the latter case, enantiopure bis-thioureas were the most effective HBDs to promote a chiral induction (diastereoselective recognition, Pfeiffer effect); the ECD results being rationalized by time-dependent density functional theory (TDDFT) calculations. Based on these experiments, bis-thioureas were used as chiral reagents in asymmetric 1,3-dipolar cycloadditions of structurally-related nitrones; the ECD sensing of the stereoinduction between bis-thioureas and the oximate serving as an indirect method of selection of the most effective HBD for asymmetric synthesis.

Excited-state symmetry breaking in quadrupolar pull-push-pull molecules: dicyanovinyl vs. cyanophenyl acceptors

A significant number of quadrupolar dyes behave as their dipolar analogues when photoexcited in polar environments. This is due to the occurrence of excited-state symmetry breaking (ES-SB), upon which the electronic excitation, initially distributed over the whole molecule, localises preferentially on one side. Here, we investigate the ES-SB properties of two A-D-A dyes, consisting of a pyrrolo-pyrrole donor (D) and either cyanophenyl or dicyanovinyl acceptors (A). For this, we use time-resolved vibrational spectroscopy, comparing IR absorption and femtosecond stimulated Raman spectroscopies. Although dicyanovinyl is a stronger electron-withdrawing group, ES-SB is not observed with the dicyanovinyl-based dye even in highly polar media, whereas it already takes place in weakly polar solvents with dyes containing cyanophenyl accepting groups. This difference is attributed to the large electronic coupling between the D-A branches in the former dye, whose loss upon symmetry breaking cannot be counterbalanced by a gain in solvation energy. Comparison with analogues of the cyanophenyl-based dye containing different spacers reveals that interbranch coupling does not so much depend on the distance between the D-A subunits than on the nature of the spacer. We show that transient Raman spectra probe different modes of these centrosymmetric molecules but are consistent with the transient IR data. However, lifetime broadening of the Raman bands, probably due to the resonance enhancement, may limit the application of this technique for monitoring ES-SB.

Engineering ligand chemistry on Au25 nanoclusters: from unique ligand addition to precisely controllable ligand exchange

Au25 nanoclusters (NCs) protected by 18 thiol-ligands (Au25SR18, SR is a thiolate ligand) are the prototype of atomically precise thiolate-protected gold NCs. Studies concerning the alteration of the number of surface ligands for a given Au25SR18 NC are scarce. Herein we report the conversion of hydrophobic Au25PET18 (PET = 2-phenylethylthiolate) NCs to Au25SR19 [Au25PET18(metal complex)1] induced by ligand exchange reactions (LERs) with thiolated terpyridine-metal complexes (metal complex, metal = Ru, Fe, Co, Ni) under mild conditions (room temperature and low amounts of incoming ligands). Interestingly, we found that the ligand addition reaction on Au25PET18 NCs is metal dependent. Ru and Co complexes preferentially lead to the formation of Au25SR19 whereas Fe and Ni complexes favor ligand exchange reactions. High-resolution electrospray ionization mass spectrometry (HRESI-MS) was used to determine the molecular formula of Au25SR19 NCs. The photophysical properties of Au25PET18(Ru complex)1 are distinctly different from Au25PET18. The absorption spectrum is drastically changed upon addition of the extra ligand and the photoluminescence quantum yield of Au25PET18(Ru complex)1 is 14 times and 3 times higher than that of pristine Au25PET18 and Au25PET17(Ru complex)1, respectively. Interestingly, only one surface ligand (PET) could be substituted by the metal complex when neutral Au25PET18 was used for ligand exchange whereas two ligands could be exchanged when starting with negatively charged Au25PET18. This charge dependence provides a strategy to precisely control the number of exchanged ligands at the surface of NCs.

New Insights on the Palaeo-archaeological Potential of the Niokolo-Koba National Park, Senegal

The study of the Palaeolithic in Senegal has made considerable progress in the last decade and has provided a renewed vision of the behavioral evolution of prehistoric populations in West Africa. The cultural trajectories within the region seem to be highly variable and bear witness to strong behavioral dynamics, the mechanisms of which still need to be better understood. However, the number of reliable, dated, and stratified sites, as well as the palaeoenvironmental data providing a context for populations in their palaeolandscapes, is still scarce. In order to provide new and solid data, we conducted new archaeological survey in the Niokolo-Koba National Park in south-central Senegal, aiming at a preliminary identification of Pleistocene and early Holocene sedimentary deposits. Here, we report an overview of the newly discovered industries found in different contexts. Most of the 27 identified sites show surface and out-of-context assemblages, but other sites are stratified and have all the criteria to justify the development of a long-term archaeological, geochronological, geomorphological, and palaeobotanical project. The Niokolo-Koba National Park, through which the Gambia River flows, is characterized by an abundance of sources of knappable material and by well-preserved sedimentary sequences. Therefore, archaeological research in the Niokolo-Koba National Park has the potential to provide major milestones in our understanding of the evolutionary dynamics at work in West Africa during the early periods of occupation of the region.

Mitochondrial pyruvate metabolism regulates the activation of quiescent adult neural stem cells

Cellular metabolism is important for adult neural stem/progenitor cell (NSPC) behavior. However, its role in the transition from quiescence to proliferation is not fully understood. We here show that the mitochondrial pyruvate carrier (MPC) plays a crucial and unexpected part in this process. MPC transports pyruvate into mitochondria, linking cytosolic glycolysis to mitochondrial tricarboxylic acid cycle and oxidative phosphorylation. Despite its metabolic key function, the role of MPC in NSPCs has not been addressed. We show that quiescent NSPCs have an active mitochondrial metabolism and express high levels of MPC. Pharmacological MPC inhibition increases aspartate and triggers NSPC activation. Furthermore, genetic Mpc1 ablation in vitro and in vivo also activates NSPCs, which differentiate into mature neurons, leading to overall increased hippocampal neurogenesis in adult and aged mice. These findings highlight the importance of metabolism for NSPC regulation and identify an important pathway through which mitochondrial pyruvate import controls NSPC quiescence and activation.

A flexible framework for anomaly Detection via dimensionality reduction

Anomaly detection is challenging, especially for large datasets in high dimensions. Here, we explore a general anomaly detection framework based on dimensionality reduction and unsupervised clustering. DRAMA is released as a general python package that implements the general framework with a wide range of built-in options. This approach identifies the primary prototypes in the data with anomalies detected by their large distances from the prototypes, either in the latent space or in the original, high-dimensional space. DRAMA is tested on a wide variety of simulated and real datasets, in up to 3000 dimensions, and is found to be robust and highly competitive with commonly used anomaly detection algorithms, especially in high dimensions. The flexibility of the DRAMA framework allows for significant optimization once some examples of anomalies are available, making it ideal for online anomaly detection, active learning, and highly unbalanced datasets. Besides, DRAMA naturally provides clustering of outliers for subsequent analysis.

Analytical separation techniques: toward achieving atomic precision in nanomaterials science

The size- and shape-dependence of the properties are the most characteristic features of nanoscale matter. In many types of nanomaterials, there is a size regime wherein every atom counts. In order to fully realize the idea of 'maneuvering things atom by atom' envisioned by Richard Feynman, synthesis and separation of nanoscale matter with atomic precision are essential. It is therefore not surprising that analytical separation techniques have contributed tremendously toward understanding the size- as well as shape-dependent properties of nanomaterials. Fascinating properties of nanomaterials would not have been explored without the use of these techniques. Here we discuss the pivotal role of analytical separation techniques in the progress of nanomaterials science. We begin with a brief overview of some of the key analytical separation techniques that are of tremendous importance in nanomaterials research. Then we describe how each of these techniques has contributed to the advancements in nanomaterials science taking some of the nanosystems as examples. We discuss the limitations and challenges of these techniques and future perspectives.

Circularly polarized luminescence from Tb(III) interacting with chiral polyether macrocycles

A straightforward two-step synthesis protocol affords a series of chiral amide-based bis-pyridine substituted polyether macrocycles. One ligand is particularly able to complex terbium(III) ions spontaneously. Upon complexation, interesting chiroptical properties are observed both in absorbance (ECD) and in fluorescence (CPL). In ligand-centered electronic circular dichroism, a sign inversion coupled with a signal enhancement is measured; while an easily detectable metal-centered circularly polarized luminescence with a glum of 0.05 is obtained for the main 5D4 → 7F5 terbium transition. The coordination mode and structure of the complex was studied using different analysis methods (NMR analysis, spectrophotometric titration and solid-state elucidation).

Torsional disorder and planarization dynamics: 9,10-bis(phenylethynyl)anthracene as a case study

Conjugated molecules with phenylethynyl building blocks are usually characterised by torsional disorder at room temperature. They are much more rigid in the electronic excited state due to conjugation. As a consequence, the electronic absorption and emission spectra do not present a mirror-image relationship. Here, we investigate how torsional disorder affects the excited state dynamics of 9,10-bis(phenylethynyl)anthracene in solvents of different viscosities and in polymers, using both stationary and ultrafast electronic spectroscopies. Temperature-dependent measurements reveal inhomogeneous broadening of the absorption spectrum at room temperature. This is confirmed by ultrafast spectroscopic measurements at different excitation wavelengths. Red-edge irradiation excites planar molecules that return to the ground state without significant structural dynamics. In this case, however, re-equilibration of the torsional disorder in the ground state can be observed. Higher-energy irradiation excites torsionally disordered molecules, which then planarise, leading to important spectral dynamics. The latter is found to occur partially via viscosity-independent inertial motion, whereas it is purely diffusive in the ground state. This dissimilarity is explained in terms of the steepness of the potential along the torsional coordinate.

Evidence for stereoelectronic effects in ligand exchange reactions on Au25 nanoclusters

Ligand exchange reaction (LER) is an important post-synthesis strategy and has been studied widely. The mechanism of this dynamic process for gold nanoclusters proved to be associative (SN2). Many factors affect the LER of clusters, including stability, solubility, chirality, electronic properties and so on. Some of these factors are not well understood and need further exploration. Here, we use a chiral fluoro-substituted ligand (R)-5,5',6,6',7,7',8,8'-octafluoro-[1,1'-binaphthalene]-2,2'-dithiol (8F-R-BINAS) to investigate the stereoelectronic and stereospecific effects during LER on achiral Au₂₅ cluster. It is demonstrated that the fluorine-substituted BINAS significantly decreases the LER reactivity both at the molecule and the related cluster level. The stereoelectronic effect is global and can be transmitted to the cluster surface. In contrast, the stereospecific effect is marginal.

Sarcopenia in Chronic Kidney Disease: A Scoping Review of Prevalence, Risk Factors, Association with Outcomes, and Treatment

Sarcopenia, a condition characterized by loss of skeletal muscle mass and function, has important clinical ramifications. We aimed to map the existing literature about prevalence, risk factors, associated adverse outcomes, and treatment of sarcopenia in individuals with chronic kidney disease (CKD). A scoping review of the literature was conducted to identify relevant articles published from databases' inception to September 2019. Individuals with CKD, regardless of their disease stage and their comorbidities, were included. Only studies with sarcopenia diagnosed using both muscle mass and function, based on published consensus definitions, were included. For studies on treatment, only randomized controlled trials with at least one sarcopenia parameter as an outcome were included. Our search yielded 1318 articles, of which 60 from were eligible for this review. The prevalence of sarcopenia ranged from 4 to 42% according to the definition used, population studied, and the disease stage. Several risk factors for sarcopenia were identified including age, male gender, low BMI, malnutrition, and high inflammatory status. Sarcopenia was found to be associated with several adverse outcomes, including disabilities, hospitalizations, and mortality. In CKD subjects, several therapeutic interventions have been assessed in randomized controlled trial with a muscle mass, strength, or function endpoint, however, studies focusing on sarcopenic CKD individuals are lacking. The key interventions in the prevention and treatment of sarcopenia in CKD seem to be aerobic and resistance exercises along with nutritional interventions. Whether these interventions are effective to treat sarcopenia and prevent clinical consequences in this population remains to be fully determined.

Confidence and use of physical examination and point-of-care ultrasonography for detection of abdominal or pleural free fluid. A cross-sectional survey

Physical examination (PE) has always been a corner stone of medical practice. The recent advances in imaging and fading of doctors' ability in performing it, however, raised doubts on PE usefulness. Point-of-care ultrasonography (POCUS) is gaining ground in medicine with the detection of free fluids being one of its main applications. To estimate physicians' confidence and use of PE and POCUS for the detection of abdominal or pleural free fluid, we conducted a cross-sectional survey. In all, 246 internal and emergency medicine physicians answered to the survey (197 in-hospital physicians and 49 general practitioners; response rate 28.5%). Almost all declared to perform PE in case of suspected ascites or pleural effusion (88% and 90%, respectively). The highest rates of confidence were observed in conventional PE signs (91% for diminished breath sounds, 80% for dullness to thorax percussion, and 66% for abdominal flank dullness). For the remaining signs, rates of confidence were less than 53%. Physicians with > 15 years of experience and POCUS-naïve doctors reported higher confidence in PE. Most of emergency and almost half of internal medicine physicians (78% and 44%, respectively) attended a structured POCUS course. POCUS use was higher among trained physicians for both ascites (84% vs 50%, p < 0.001) and pleural effusion (80% vs 34%, p < 0.001). Similarly, higher POCUS use was observed in younger physicians. In conclusion, PE is frequently performed and rates of confidence are low for most PE signs, especially among young doctors and POCUS users. This detailed inventory suggests an ongoing shift towards POCUS integration in clinical practice.

Association between mood disorders and frequent emergency department use: a cross-sectional study

OBJECTIVES

Frequent emergency department (ED) use is a growing problem that is associated with poor patient outcomes and increased health care costs. Our objective was to analyze the association between mood disorders and the incidence of frequent ED use.

METHODS

We used the Canadian Community Health Survey conducted by Statistics Canada, 2015-2016. Mood disorder was defined as depression, bipolar disorder, mania, or dysthymia. Frequent ED use was defined as 4 or more visits in the year preceding the interview. Multivariable log-binomial regression models were used to determine the associations between mood disorders and frequent ED use.

RESULTS

Among the 99,009 participants, 8.4% had mood disorders, 80.3% were younger than 65, and 2.2% were frequent ED users. Mood disorders were significantly associated with the 1-year cumulative incidence of frequent ED use (RR = 2.5, 95% CI 2.2-2.7), after adjusting for several potential confounders.

CONCLUSIONS

This national survey showed that people with a mood disorder had a three-fold risk of frequent ED use, compared to people without mood disorder. These results can inform the development of policies and targeted interventions aimed at identifying and supporting ED patients with mood disorder.

Understanding motivation for implementing cooperative learning methods: a value-based approach

The implementation of cooperative learning methods remains disparate in primary schools despite their widely recognised benefits. To explain this paradox, we first examined whether teachers’ inclination towards cooperative methods is motivated by their values. Second, we tested whether motivational connections between personal values and cooperative methods are undermined when conflictual values are activated in context. Study 1 demonstrated that pre-service teachers strongly endorsed self-transcendence (ST) values (expressing compatible motivations with cooperation) relative to self-enhancement (SE) values (expressing conflictual motivations with cooperation). Adherence to ST values was also positively associated with their beliefs and attitudes regarding cooperative methods. In Studies 2, 3 and 4, educational sciences students were experimentally exposed to different contexts, wherein ST, SE or neutral values were promoted. Our findings indicate that when SE values were emphasised in the context, the positive association between ST values and beliefs/attitudes regarding cooperative methods disappeared. Although the results of Study 4 regarding the intention to use cooperative methods were not statistically significant, the pattern was similar. Finally, Study 5 showed that primary school teachers’ ST values positively predicted the self-reported use of cooperative methods when they perceived their school to weakly endorse SE values, but not when they perceived it to strongly endorse them.

Pathways to performance in undergraduate medical students: role of conscientiousness and the perceived educational environment

This study examined conscientiousness and the perceived educational environment as independent and interactive predictors of medical students' performance within Biggs' theoretical model of learning. Conscientiousness, the perceived educational environment, and learning approaches were assessed at the beginning of the third year in 268 medical students at the University of Geneva, Switzerland. Performance was examined at the end of the third year via a computer-based assessment (CBA) and the Objective Structured Clinical Examination (OSCE). Path analysis was used to test the proposed model, whereby conscientiousness and the perceived educational environment predicted performance directly and indirectly via students' learning approaches. A second model included interaction effects. The proposed model provided the best fit and explained 45% of the variance in CBA performance, and 23% of the variance in OSCE performance. Conscientiousness positively predicted CBA performance directly (β = 0.19, p < 0.001) and indirectly via a deep learning approach (β = 0.05, p = 0.012). The perceived educational environment positively predicted CBA performance indirectly only (β = 0.02, p = 0.011). Neither conscientiousness nor the perceived educational environment predicted OSCE performance. Model 2 had acceptable, but less optimal fit. In this model, there was a significant cross-over interaction effect (β = 0.16, p < 0.01): conscientiousness positively predicted OSCE performance when perceptions of the educational environment were the most positive, but negatively predicted performance when perceptions were the least positive. The findings suggest that both conscientiousness and perceptions of the educational environment predict CBA performance. Research should further examine interactions between personality traits and the medical school environment to inform strategies aimed at improving OSCE performance.

What the presence of regulated chemical elements in beached lacustrine plastics can tell us: the case of Swiss lakes

Plastics (n = 3880) have been sampled from 39 beaches of ten Swiss lakes of varying sizes, hydrodynamics, and catchments, with a selection (n = 598) analysed for potentially hazardous (and regulated) chemical elements (As, Ba, Br, Cd, Cr, Hg, Pb, Sb, Se) by X-ray fluorescence spectrometry. Plastic objects and fragments with identifiable or unidentifiable origins were present on all beaches surveyed, and were often most abundant in proximity to major riverine inputs. Chemical elements were detected in between two (Hg) and 340 (Ba) samples with maximum concentrations exceeding 2% by weight for Ba, Cd, Cr, Pb, and Sb. Inter-element relationships and characteristics of the samples suggest that elements are largely present as various additives, including pigments (e.g., Cd₂SSe, PbCrO₄), stabilizers (in polyvinyl chloride), and flame retardants (Br). Observations are similar to, and complement, those previously reported in Switzerland's largest lake (Lake Geneva). Comparison of concentrations of targeted chemical elements in beached plastic with currently used plastics illustrate the interest of these types of measurements in providing an insight into the persistence of plastics in standing stocks and in lakes. This information could help to introduce management schemes that consider whether plastic pollution is new or old and act accordingly.

How can the orthopedic surgeon ensure optimal vitamin D status in patients operated for an osteoporotic fracture?

In this narrative review, the role of vitamin D deficiency in the pathophysiology, healing of fragility fractures, and rehabilitation is discussed. Vitamin D status can be assessed by measuring serum 25(OH)-vitamin D level with standardized assays. There is a high prevalence of vitamin D insufficiency (25(OH)D < 50 nmol/l (i.e., 20 ng/mL)) or deficiency (25(OH)D < 25 nmol/l (i.e., 10 ng/mL)) in patients with fragility fractures and especially in those with a hip fracture. The evidence on the effects of vitamin D deficiency and/or vitamin D supplementation on fracture healing and material osseointegration is still limited. However, it appears that vitamin D have a rather positive influence on these processes. The fracture liaison service (FLS) model can help to inform orthopedic surgeons, all caregivers, and fractured patients about the importance of optimal vitamin D status in the management of patients with fragility fractures. Therefore, vitamin D status should be included in Capture the Fracture® program as an outcome of FLS in addition to dual-energy X-ray absorptiometry (DXA) and specific antiosteoporosis medication. Vitamin D plays a significant role in the pathophysiology and healing of fragility fractures and in rehabilitation after fracture. Correction of vitamin D deficiency should be one of the main outcomes in fracture liaison services.

Longitudinal Analysis of Inflammatory Response to SARS-CoV-2 in the Upper Respiratory Tract Reveals an Association with Viral Load, Independent of Symptoms

Background

SARS-CoV-2 infection leads to high viral loads in the upper respiratory tract that may be determinant in virus dissemination. The extent of intranasal antiviral response in relation to symptoms is unknown. Understanding how local innate responses control virus is key in the development of therapeutic approaches.

Methods

SARS-CoV-2-infected patients were enrolled in an observational study conducted at the Geneva University Hospitals, Switzerland, investigating virological and immunological characteristics. Nasal wash and serum specimens from a subset of patients were collected to measure viral load, IgA specific for the S1 domain of the spike protein, and a cytokine panel at different time points after infection; cytokine levels were analyzed in relation to symptoms.

Results

Samples from 13 SARS-CoV-2-infected patients and six controls were analyzed. We found an increase in CXCL10 and IL-6, whose levels remained elevated for up to 3 weeks after symptom onset. SARS-CoV-2 infection also induced CCL2 and GM-CSF, suggesting local recruitment and activation of myeloid cells. Local cytokine levels correlated with viral load but not with serum cytokine levels, nor with specific symptoms, including anosmia. Some patients had S1-specific IgA in the nasal cavity while almost none had IgG.

Conclusion

The nasal epithelium is an active site of cytokine response against SARS-CoV-2 that can last more than 2 weeks; in this mild COVID-19 cohort, anosmia was not associated with increases in any locally produced cytokines.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10875-021-01134-z.

Language policy and planning: a discussion on the complexity of language matters and the role of computational methods

In this paper I argue in favour of the adoption of an interdisciplinary approach based on computational methods for the development of language policies. As a consequence of large-scale phenomena such as globalization, economic and political integration and the progress in information and communication technologies, social systems have become increasingly interconnected. Language-related systems are no exception. Besides, language matters are never just language matters. Their causes and consequences are to be found in many seemingly unrelated fields. Therefore, we can no longer overlook the numerous variables involved in the unfolding of linguistic and sociolinguistic phenomena if we wish to develop effective language policy measures. A genuinely interdisciplinary approach is key to address language matters (as well as many other public policy matters). In this regard, the tools of complexity theory, such as computational methods based on computer simulations, have proved useful in other fields of public policy.

Civil Disobedience in Times of Pandemic: Clarifying Rights and Duties

This paper seeks to investigate and assess a particular form of relationship between the State and its citizens in the context of the COVID-19 pandemic, namely that of obedience to the law and its related right of protest through civil disobedience. We do so by conducting an analysis and normative evaluation of two cases of disobedience to the law: (1) healthcare professionals refusing to attend work as a protest against unsafe working conditions, and (2) citizens who use public demonstration and deliberately ignore measures of social distancing as a way of protesting against lockdown. While different in many aspects, both are substantially similar with respect to one element: their respective protesters both rely on unlawful actions in order to bring change to a policy they consider unjust. We question the extent to which healthcare professionals may participate in civil disobedience with respect to the duty of care intrinsic to the medical profession, and the extent to which opponents of lockdown and confinement measures may reasonably engage in protests without endangering the lives and basic rights of non-dissenting citizens. Drawing on a contractualist normative framework, our analysis leads us to conclude that while both cases qualify as civil disobedience in the descriptive sense, only the case of healthcare professionals qualifies as morally justified civil disobedience.

Functionathon: a manual data mining workflow to generate functional hypotheses for uncharacterized human proteins and its application by undergraduate students

About 10% of human proteins have no annotated function in protein knowledge bases. A workflow to generate hypotheses for the function of these uncharacterized proteins has been developed, based on predicted and experimental information on protein properties, interactions, tissular expression, subcellular localization, conservation in other organisms, as well as phenotypic data in mutant model organisms. This workflow has been applied to seven uncharacterized human proteins (C6orf118, C7orf25, CXorf58, RSRP1, SMLR1, TMEM53 and TMEM232) in the frame of a course-based undergraduate research experience named Functionathon organized at the University of Geneva to teach undergraduate students how to use biological databases and bioinformatics tools and interpret the results. C6orf118, CXorf58 and TMEM232 were proposed to be involved in cilia-related functions; TMEM53 and SMLR1 were proposed to be involved in lipid metabolism and C7orf25 and RSRP1 were proposed to be involved in RNA metabolism and gene expression. Experimental strategies to test these hypotheses were also discussed. The results of this manual data mining study may contribute to the project recently launched by the Human Proteome Organization (HUPO) Human Proteome Project aiming to fill gaps in the functional annotation of human proteins. Database URL: http://www.nextprot.org.

Varieties of dispositional essentialism about natural laws

An important task for metaphysicians and philosophers of science is to account for laws of nature - in particular, how they distinguish themselves from 'mere' regularities, and the modal force they are endowed with, 'natural necessity'. Dispositional essentialism about laws (for short: 'essentialism') is roughly the view that laws distinguish themselves by being grounded in the essences of natural entities (e.g. kinds, properties). This paper does not primarily concern how essentialism compares to its main rivals - Humeanism and Armstrongeanism. Rather, it distinguishes and comparatively assesses various brands of essentialism - which mainly differ as to where exactly they take laws to find their essentialist sources (e.g. in particular entities, like electrons, or in larger pluralities of entities, or in the world as a whole), and what they take to be the targets of laws, namely what they apply to. Yet, this internal comparison is not unrelated to the more general debate about laws: the main criteria with which I compare these essentialist views concern how they can deal with some of the main objections faced by essentialism in general (the modal status it typically attributes to laws, which some think is too strong; and its alleged incapacity to account for the most 'general' laws, like conservation laws), and how they can keep what is arguably the main intuitive advantage of essentialism over its rivals (the fact that, on this view, things "govern themselves"). Thus, the paper also concerns the relative position of essentialism in the larger debate about laws - ultimately bringing support to it.

An efficient algorithm for solving piecewise-smooth dynamical systems

This article considers the numerical treatment of piecewise-smooth dynamical systems. Classical solutions as well as sliding modes up to codimension-2 are treated. An algorithm is presented that, in the case of non-uniqueness, selects a solution that is the formal limit solution of a regularized problem. The numerical solution of a regularized differential equation, which creates stiffness and often also high oscillations, is avoided.

Natural history and treatment options of radiation-induced brain cavernomas: a systematic review

Radiation-induced cavernous malformations (RICMs) are delayed complications of brain irradiation during childhood. Its natural history is largely unknown and its incidence may be underestimated as RCIMS tend to develop several years following radiation. No clear consensus exists regarding the long-term follow-up or treatment. A systematic review of Embase, Cochrane Library, PubMed, Google Scholar, and Web of Science databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, was performed. Based on our inclusion/exclusion criteria, 12 articles were included, totaling 113 children with RICMs, 86 were treated conservatively, and 27 with microsurgery. We were unable to precisely define the incidence and natural history from this data. The mean age at radiation treatment was 7.3 years, with a slight male predominance (54%) and an average dose of 50.0 Gy. The mean time to detection of RICM was 9.2 years after radiation. RICM often developed at distance from the primary lesion, more specifically frontal (35%) and temporal lobe (34%). On average, 2.6 RICMs were discovered per child. Sixty-seven percent were asymptomatic. Twenty-one percent presented signs of hemorrhage. Clinical outcome was favorable in all children except in 2. Follow-up data were lacking in most of the studies. RICM is most often asymptomatic but probably an underestimated complication of cerebral irradiation in the pediatric population. Based on the radiological development of RICMs, many authors suggest a follow-up of at least 15 years. Studies suggest observation for asymptomatic lesions, while surgery is reserved for symptomatic growth, hemorrhage, or focal neurological deficits.

Arginine-dependent immune responses

A growing body of evidence indicates that, over the course of evolution of the immune system, arginine has been selected as a node for the regulation of immune responses. An appropriate supply of arginine has long been associated with the improvement of immune responses. In addition to being a building block for protein synthesis, arginine serves as a substrate for distinct metabolic pathways that profoundly affect immune cell biology; especially macrophage, dendritic cell and T cell immunobiology. Arginine availability, synthesis, and catabolism are highly interrelated aspects of immune responses and their fine-tuning can dictate divergent pro-inflammatory or anti-inflammatory immune outcomes. Here, we review the organismal pathways of arginine metabolism in humans and rodents, as essential modulators of the availability of this semi-essential amino acid for immune cells. We subsequently review well-established and novel findings on the functional impact of arginine biosynthetic and catabolic pathways on the main immune cell lineages. Finally, as arginine has emerged as a molecule impacting on a plethora of immune functions, we integrate key notions on how the disruption or perversion of arginine metabolism is implicated in pathologies ranging from infectious diseases to autoimmunity and cancer.

Thickness of the particle-free layer near charged interfaces in suspensions of like-charged nanoparticles

When a suspension of charged nanoparticles is in contact with a like-charged water-solid interface, next to this interface a particle-free layer is formed. The present study provides reliable measurements of the thickness of this particle-free layer with three different techniques, namely optical reflectivity, quartz crystal microbalance (QCM), and direct force measurements with atomic force microscopy (AFM). Suspensions of negatively charged nanoparticles of different size and type are investigated. When the measured layer thickness is normalized to the particle size, one finds that this normalized thickness shows universal inverse square root dependence on the particle volume fraction. This universal dependence can be also derived from Poisson-Boltzmann theory for highly asymmetric electrolytes, whereby one has to assume that the nanoparticles represent the multivalent coions.

Does Heart Rate Variability Biofeedback Enhance Executive Functions Across the Lifespan? A Systematic Review

The scope of this systematic review was to summarize the existing literature on the effects of heart rate variability biofeedback (HRV-BF) on executive functions (EFs) across the lifespan. Specifically, it aimed to investigate the factors that may affect the efficacy of HRV-BF interventions, such as the study population, duration and intensity of the intervention, or the technical equipment. This review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that measured and presented at least one EF were included. We included controlled and uncontrolled trials involving clinical and general populations. From the initial list of 137 papers, 16 final studies were reviewed, with 777 participants. Fifty-six percent of the studies included in this review reported significant positive effects of HRV-BF intervention on at least one EF. Attention was the domain that most often benefited from the intervention. The majority of EF improvements (78%) occurred in studies that addressed patient populations or individuals that may present particular profiles: individuals exposed to stress, professional athletes, war veterans, children and adults with ADHD, and clinical older patients. The remaining studies (22%) that reported significant improvements focused on the general population. Efficacy was neither related to the duration or intensity of the intervention nor related to the technical equipment. Overall, our review shows that HRV-BF may be beneficial (a) to increase attentional skills, inhibition, and working memory and (b) when targeting more vulnerable individuals or individuals with particular profiles. However, further development of standardized, controlled protocols and consistent reporting of effect sizes may contribute to establishing the relevance of HRV-BF biofeedback interventions within the field of cognitive enhancement.

A New Argument for the Groundedness of Grounding Facts

Many philosophers have recently been impressed by an argument to the effect that all grounding facts about "derivative entities"-e.g. the facts expressed by the (let us suppose) true sentences 'the fact that Beijing is a concrete entity is grounded in the fact that its parts are concrete' and 'the fact that there are cities is grounded in the fact that p', where 'p' is a suitable sentence couched in the language of particle physics-must themselves be grounded. This argument relies on a principle, Purity, which states that facts about derivative entities are non-fundamental. Purity is questionable. In this paper, I introduce a new argument-the argument from Settledness-for a similar conclusion but which does not rely on Purity. The conclusion of the new argument is that every "thick" grounding fact is grounded, where a grounding fact [F is grounded in G, H, …] is said to be thick when at least one of F, G, H, … is a fact-a condition that is automatically satisfied if grounding is factive. After introducing the argument, I compare it with the argument from Purity, and I assess its cogency relative to the relevant accounts of the connections between grounding and fundamentality that are available in the literature.

Increased oxytocin release precedes hyponatremia after pituitary surgery

PURPOSE

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is a well-known complication of transsphenoidal pituitary surgery, related to inappropriate secretion of arginine vasopressin (AVP). Its diagnosis is based on hyponatremia, with a peak of occurrence around day 7 after surgery and, to date, no early marker has been reported. In particular, copeptin levels are not predictive of hyponatremia in this case. Oxytocin (OXT) is secreted into the peripheral blood by axon terminals adjacent to those of AVP neurons in the posterior pituitary. Besides its role in childbirth and lactation, recent evidences suggested a role for OXT in sodium balance. The contribution of this hormone in the dysnatremias observed after pituitary surgery has however never been investigated.

METHODS

We analyzed the urinary output of OXT in patients subjected to transsphenoidal pituitary surgery.

RESULTS

While OXT excretion remained stable in patients who presented a normonatremic postoperative course, patients who were later diagnosed with SIADH-related hyponatremia presented with a significantly increased urinary secretion of OXT 4 days after surgery.

CONCLUSION

Taken together, these results show for the first time that urinary OXT output remains normally stable after transsphenoidal pituitary surgery. OXT excretion however becomes abnormally high on or around 4 days after surgery in patients later developing hyponatremia, suggesting that this abnormal dynamics of OXT secretion might serve as an early marker for transsphenoidal surgery-related hyponatremia attributed to SIADH.

A kind route from grounding to fundamentality

I offer an account of fundamentality for facts in terms of metaphysical grounding. The account does justice to the idea that whether a fact is absolutely fundamental, and whether a fact is more fundamental than, or as fundamental as, another fact, are a matter of where in a grounding-induced hierarchy of kinds of facts these facts appear.

Performances of automated digital imaging of Gram-stained slides with on-screen reading against manual microscopy

The objective of this study was to evaluate the performances of the automated digital imaging of Gram-stained slides against manual microscopy. Four hundred forty-three identified Gram-stained slides were included in this study. When both methods agreed, we considered the results as correct, and no further examination was carried out. Whenever the methods gave discrepant results, we reviewed the digital images and the glass slides by manual microscopy to avoid incorrectly read smears. The final result was a consensus of multiple independent reader interpretations. Among the 443 slides analyzed in this study, 101 (22.8%) showed discrepant results between the compared methods. The rates of discrepant results according to the specimen types were 5.7% (9/157) for positive blood cultures, 42% (60/142) for respiratory tract specimens, and 22% (32/144) for sterile site specimens. After a subsequent review of the discrepant slides, the final rate of discrepancies dropped to 7.0% (31/443). The overall agreement between the compared methods and the culture results reached 78% (345/443) and 79% (349/443) for manual microscopy and automated digital imaging, respectively. According to culture results, the specificity for automated digital imaging and manual microscopy were 90.8% and 87.7% respectively. In contrast, sensitivity was 84.1% for the two compared methods. The discrepant results were mostly encountered with microorganism morphologies of rare occurrence. The results reported in this study emphasize that on-screen reading is challenging, since the recognition of morphologies on-screen can appear different as compared to routine manual microscopy. Monitoring of Gram stain errors, which is facilitated by automated digital imaging, remains crucial for the quality control of reported Gram stain results.

The perspectives of mapping and monitoring of the sense of self in neurosurgical patients

Surgical treatment of tumors, epileptic foci or of vascular origin, requires a detailed individual pre-surgical workup and intra-operative surveillance of brain functions to minimize the risk of post-surgical neurological deficits and decline of quality of life. Most attention is attributed to language, motor functions, and perception. However, higher cognitive functions such as social cognition, personality, and the sense of self may be affected by brain surgery. To date, the precise localization and the network patterns of brain regions involved in such functions are not yet fully understood, making the assessment of risks of related post-surgical deficits difficult. It is in the interest of neurosurgeons to understand with which neural systems related to selfhood and personality they are interfering during surgery. Recent neuroscience research using virtual reality and clinical observations suggest that the insular cortex, medial prefrontal cortex, and temporo-parietal junction are important components of a neural system dedicated to self-consciousness based on multisensory bodily processing, including exteroceptive and interoceptive cues (bodily self-consciousness (BSC)). Here, we argue that combined extra- and intra-operative approaches using targeted cognitive testing, functional imaging and EEG, virtual reality, combined with multisensory stimulations, may contribute to the assessment of the BSC and related cognitive aspects. Although the usefulness of particular biomarkers, such as cardiac and respiratory signals linked to virtual reality, and of heartbeat evoked potentials as a surrogate marker for intactness of multisensory integration for intra-operative monitoring has to be proved, systemic and automatized testing of BSC in neurosurgical patients will improve future surgical outcome.

Combined spectroscopic studies on post-functionalized Au25 cluster as an ATR-FTIR sensor for cations

Recently, significant research activity has been devoted to thiolate-protected gold clusters due to their attractive optical and electronic properties. These properties as well as solubility and stability can be controlled by post-synthetic modification strategies. Herein, the ligand exchange reaction between Au25(2-PET)18 cluster (where 2-PET is 2-phenylethanethiol) and di-thiolated crown ether (t-CE) ligands bearing two chromophores was studied. The post-functionalization aimed to endow the cluster with ion binding properties. The exchange reaction was followed in situ by UV-vis, 1H NMR and HPLC. MALDI mass analysis revealed the incorporation of up to 5 t-CE ligands into the ligand shell. Once functionalized MALDI furthermore showed complexation of sodium ions to the cluster. ATR-FTIR spectroscopic studies using aqueous solutions of K+, Ba2+, Gd3+ and Eu3+ showed noticeable spectral shifts of the C-O stretching band around 1100 cm-1 upon complexation. Further spectral changes point towards a conformational change of the two chromophores that are attached to the crown ether. Density functional theory calculations indicate that the di-thiol ligand bridges two staple units on the cluster. The calculations furthermore reproduce the spectral shift of the C-O stretching vibrations upon complex formation and reveal a conformational change that involves the two chromophores attached to the crown ether. The functionalized clusters have therefore attractive ion sensing properties due to the combination of binding properties, mainly due to the crown ether, and the possibility for signal transduction via an induced conformational change involving chromophore units.

The Antiedematous Effect of Exogenous Lactate Therapy in Traumatic Brain Injury: A Physiological and Mechanistic Approach

Background

Sodium lactate (SL) has been described as an efficient therapy in treating raised intracranial pressure (ICP). However, the precise mechanism by which SL reduces intracranial hypertension is not well defined. An antiedematous effect has been proposed but never demonstrated. In this context, the involvement of chloride channels, aquaporins, or K–Cl cotransporters has also been suggested, but these mechanisms have never been assessed when using SL.

Methods

In a rat model of traumatic brain injury (TBI), we compared the effect of SL versus mannitol 20% on ICP, cerebral tissue oxygen pressure, and brain water content. We attempted to clarify the involvement of chloride channels in the antiedematous effects associated with lactate therapy in TBI.

Results

An equimolar single bolus of SL and mannitol significantly reduced brain water content and ICP and improved cerebral tissue oxygen pressure 4 h after severe TBI. The effect of SL on brain water content was much longer than that of mannitol and persisted at 24 h post TBI. Western blot and immunofluorescence staining analyses performed 24 h after TBI revealed that SL infusion is associated with an upregulation of aquaporin 4 and K–Cl cotransporter 2.

Conclusions

SL is an effective therapy for treating brain edema after TBI. This study suggests, for the first time, the potential role of chloride channels in the antiedematous effect induced by exogenous SL.

Ligand exchange reactions on thiolate-protected gold nanoclusters

As a versatile post-synthesis modification method, ligand exchange reaction exhibits great potential to extend the space of accessible nanoclusters. In this review, we summarized this process for thiolate-protected gold nanoclusters. In order to better understand this reaction we will first provide the necessary background on the synthesis and structure of various gold clusters, such as Au25(SR)18, Au38(SR)24, and Au102(SR)44. The previous investigations illustrated that ligand exchange is enabled by the chemical properties and flexible gold-sulfur interface of nanoclusters. It is generally believed that ligand exchange follows a SN2-like mechanism, which is supported both by experiments and calculations. More interesting, several studies show that ligand exchange takes place at preferred sites, i.e. thiolate groups -SR, on the ligand shell of nanoclusters. With the help of ligand exchange reactions many functionalities could be imparted to gold nanoclusters including the introduced of chirality to achiral nanoclusters, size transformation and phase transfer of nanoclusters, and the addition of fluorescence or biological labels. Ligand exchange was also used to amplify the enantiomeric excess of an intrinsically chiral cluster. Ligand exchange reaction accelerates the prosperity of the nanocluster field, and also extends the diversity of precise nanoclusters.

Symmetry fundamentalism in quantum mechanics

Modern particle physics suggests an intriguing vision of physical reality: we are to imagine the symmetries of the world as fundamental, whereas the material constituents of the world (such as particles and fields) are ontologically derivative of them. This paper develops a novel ontology for non-relativistic quantum mechanics which gives precise metaphysical content to this vision.

Respond of the different human cranial bones to pin-type head fixation device

Background

At this juncture, there is no consensus in the literature for the use and the safety of pin-type head holders in cranial procedures.

Methods

The present analysis of the bone response to the fixation of the instrument provides data to understand its impact on the entire skull as well as associated complications. An experimental study was conducted on fresh-frozen human specimens to analyze the puncture hole due to the fixation of each single pin of the pin-type head holder. Cone-beam CT images were acquired to measure the diameter of the puncture hole caused by the instrument according to several parameters: the pin angle, the clamping force, and different neurosurgical approaches most clinically used.

Results

The deepest hole, 2.67 ± 0.27 mm, was recorded for a 35° angle and a clamping force of 270 N at the middle fossa approach. The shallowest hole was 0.62 ± 0.22 mm for the 43° angle with a pinning force of 180 N in the pterional approach. The pterional approach had a significantly different effect on the depth of the puncture hole compared with the middle fossa craniotomy for 270 N pinning at 35° angle. The puncture hole measured with the 43° angle and 180 N force in prone position is significantly different from the other approaches with the same force.

Conclusions

These results could lead to recommendations about the use of the head holder depending on the patient’s history and cranial thickness to reduce complications associated with the pin-type head holder during clinical applications.

Lockdown and Children’s Well-Being: Experiences of Children in Switzerland, Canada and Estonia

This paper addresses the well-being of children in Switzerland, Canada and Estonia, as they experienced the lockdown imposed by governments after the state of international public health emergency, declared by the World Health Organization on 30 January 2020. Suspension of school or starting with distance learning, cessation of extracurricular activities, closure of playgrounds, parks, shopping centres and loss of daily contacts with friends completely transformed children’s lives. The surveys conducted by the authors in individual ways, were all inspired by their membership to the Children’s Understandings of Well-Being network and involved the participation of 403 children aged 7–17 years old (229 girls and 174 boys). They present the emerging trends from the children’s narratives focusing on their experience of the lockdown in relation to family life, school life, contacts with friends, and in relation to space, time and self. During the lockdown leisure activities and hobbies, followed by life with friends and school life challenged relational well-being the most, while family life opened up new perspectives and generational solidarity. Staying at home and decreased physical activity impacted on the physical health of children, missing direct contacts with friends and teachers put social relations to test, fear of the virus decreased feeling safe and secure, and the lockdown restricted participation in society. The findings underline the relational nature of their well-being. More in-depth studies are needed to highlight the widening of inequalities and the balance between protection and participation of children.

Fundamentality from grounding trees

I provide and defend two natural accounts of (both relative and absolute) fundamentality for facts that do justice to the idea that the "degree of fundamentality" enjoyed by a fact is a matter of how far, from a ground-theoretic perspective, the fact is from the ungrounded facts.

Comment on "Ultrapotassic magmatism in the heyday of the Variscan Orogeny: the story of the Třebíč Pluton, the largest durbachitic body in the Bohemian Massif" by Janoušek et al

This comment addresses the incorrect treatment and presentation of data from laser ablation ICP-MS U-Pb age determinations of two samples of the Třebíč Pluton. This results in inaccurate ages and error assessment, invalidating the age interpretations of the authors. To corroborate our arguments, new high-precision chemical abrasion ID-TIMS data are presented that unequivocally define the emplacement age of the Třebíč pluton.

Fluorescence intensities of composite resins on photo images

Recording fluorescence using flash photography, may help reduce time of capture and apply effectively in clinical practice. To test methods for visualizing composite resins fluorescence by direct digital photography. Sixty-four specimen discs (1.5 × 10 mm) were prepared from 8 different composite resin brands. Their CIELAB color coordinates (L*, a*, b*) and fluorescence were measured using a portable colorimeter and a fluorescence spectrophotometer. The mean of three measurements was recorded and then specimens were photographed by a DSLR camera with two different filters (365 nm and 405 nm) mounted on a commercial macro flash. RGB values of all specimens on the photographs were measured by using Photoshop software and converted to CIELab. Data were then analyzed using Kruskal–Wallis and Dunn’s multiple comparisons tests. Correlation and regression analyses were also used to relate fluorescence and color parameters on the photographs at α = 0.05. Fluorescence and color data indicated significant differences among the materials (p < 0.05). L* a* and b* color coordinates from both photographs were highly correlated to fluorescence intensities found by the reference method (r₃₆₅ − 0.95, r₄₀₅ − 0.94), while regression analysis indicated a strong linear relationship (R²₃₆₅ − 0.88, R²₄₀₅ − 0.89). The study showed that filtered flash photography either by the use of a 365 nm or a 405 nm band pass filter can directly visualize fluorescence of composite resin materials and differences in fluorescence between them.

Forensic age estimation based on fast spin-echo proton density (FSE PD)-weighted MRI of the distal radial epiphysis

Radiation exposure is a crucial factor to consider in forensic age estimation. The various magnetic resonance imaging (MRI) modalities used in forensic age estimation avoid radiation exposure. This study examined the reliability of distal radius ossification using fast spin-echo proton density (FSE PD)–weighted MRI to estimate age. Left wrist MRI findings of 532 patients aged 10–29 years were evaluated retrospectively using the five-stage system of Dedouit et al. The intra- and interobserver reliability values were κ = 0.906 and 0.869, respectively. Based on the results, the respective minimum ages estimated for stages 4 and 5 were 13.4 and 16.1 years for females, and 15.1 and 17.3 years for males; the method could not estimate an age of 18 years in any case. FSE PD MRI analysis of the distal radius epiphysis provides supportive data and can be used when evaluating the distal radius for forensic age estimation.

Quantitative chemical mapping of plagioclase as a tool for the interpretation of volcanic stratigraphy: an example from Saint Kitts, Lesser Antilles

Establishing a quantitative link between magmatic processes occurring at depth and volcanic eruption dynamics is essential to forecast the future behaviour of volcanoes, and to correctly interpret monitoring signals at active centres. Chemical zoning in minerals, which captures successive events or states within a magmatic system, can be exploited for such a purpose. However, to develop a quantitative understanding of magmatic systems requires an unbiased, reproducible method for characterising zoned crystals. We use image segmentation on thin section scale chemical maps to segment textural zones in plagioclase phenocrysts. These zones are then correlated throughout a stratigraphic sequence from Saint Kitts (Lesser Antilles), composed of a basal pyroclastic flow deposit and a series of fall deposits. Both segmented phenocrysts and unsegmented matrix plagioclase are chemically decoupled from whole rock geochemical trends, with the latter showing a systematic temporal progression towards less chemically evolved magma (more anorthitic plagioclase). By working on a stratigraphic sequence, it is possible to track the chemical and textural complexity of segmented plagioclase in time, in this case on the order of millennia. In doing so, we find a relationship between the number of crystal populations, deposit thickness and time. Thicker deposits contain a larger number of crystal populations, alongside an overall reduction in this number towards the top of the deposit. Our approach provides quantitative textural parameters for volcanic and plutonic rocks, including the ability to measure the amount of crystal fracturing. In combination with mineral chemistry, these parameters can strengthen the link between petrology and volcanology, paving the way towards a deeper understanding of the magmatic processes controlling eruptive dynamics.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s00445-021-01476-x.