Unveiling the dynamic active site of defective carbon-based electrocatalysts for hydrogen peroxide production

Active sites identification in metal-free carbon materials is crucial for developing practical electrocatalysts, but resolving precise configuration of active site remains a challenge because of the elusive dynamic structural evolution process during reactions. Here, we reveal the dynamic active site identification process of oxygen modified defective graphene. First, the defect density and types of oxygen groups were precisely manipulated on graphene, combined with electrocatalytic performance evaluation, revealing a previously overlooked positive correlation relationship between the defect density and the 2 e- oxygen reduction performance. An electrocatalytic-driven oxygen groups redistribution phenomenon was observed, which narrows the scope of potential configurations of the active site. The dynamic evolution processes are monitored via multiple in-situ technologies and theoretical spectra simulations, resolving the configuration of major active sites (carbonyl on pentagon defect) and key intermediates (*OOH), in-depth understanding the catalytic mechanism and providing a research paradigm for metal-free carbon materials.

Facile and Scalable Mechanochemical Synthesis of Defective MoS2 with Ru Single Atoms Toward High-Current-Density Hydrogen Evolution

Designing a facile strategy to prepare catalysts with highly active sites are challenging for large-scale implementation of electrochemical hydrogen production. Herein, a straightforward and eco-friendly method by high-energy mechanochemical ball milling for mass production of atomic Ru dispersive in defective MoS2 catalysts (Ru1 @D-MoS2 ) is developed. It is found that single atomic Ru doping induces the generation of S vacancies, which can break the electronic neutrality around Ru atoms, leading to an asymmetrical distribution of electrons. It is also demonstrated that the Ru1 @D-MoS2 exhibits superb alkaline hydrogen evolution enhancement, possibly attributing to this electronic asymmetry. The overpotential required to deliver a current density of 10 mA cm-2 is as low as 107 mV, which is much lower than that of commercial MoS2 (C-MoS2 , 364 mV). Further density functional theory (DFT) calculations also support that the vacancy-coupled single Ru enables much higher electronic distribution asymmetry degree, which could regulate the adsorption energy of intermediates, favoring the water dissociation and the adsorption/desorption of H*. Besides, the long-term stability test under 500 mA cm-2 further confirms the robust performance of Ru1 @D-MoS2 . Our strategy provides a promising and practical way towards large-scale preparation of advanced HER catalysts for commercial applications.

Prediction of knee pain improvement over two years for knee osteoarthritis using a dynamic nomogram based on MRI-derived radiomics: a proof-of-concept study

OBJECTIVES

To develop and validate a nomogram to detect improved knee pain in osteoarthritis (OA) by integrating magnetic resonance imaging (MRI) radiomics signature of subchondral bone and clinical characteristics.

METHODS

Participants were selected from the Vitamin D Effects on Osteoarthritis (VIDEO) study. The primary outcome was 20% improvement of knee pain score over 2 years in participants administrated either vitamin D or placebo. Radiomics features of subchondral bone and clinical characteristics from 216 participants were extracted and analyzed. The participants were randomly split into the training and validation cohorts at a ratio of 8:2. Least absolute shrinkage and selection operator (LASSO) regression was used to select features and generate radiomics signatures. The optimal radiomics signature and clinical indicators were fitted into a nomogram using multivariable logistic regression model.

RESULTS

The nomogram showed favorable discrimination performance [AUC_training, 0.79 (95% CI: 0.72-0.79), AUC_validation, 0.83 (95% CI: 0.70-0.96)] as well as a good calibration. Additional contributing value of fusion radiomics signature to the nomogram was statistically significant (NRI, 0.23; IDI, 0.14, P < 0.001 in training cohort and NRI, 0.29; IDI, 0.18, P < 0.05 in validating cohort). Decision curve analysis confirmed the clinical usefulness of nomogram.

CONCLUSION

The radiomics-based nomogram comprising the MR radiomics signature and clinical variables achieves a favorable predictive efficacy and accuracy in differentiating improvement in knee pain among OA patients. This proof-of-concept study provides a promising way to predict clinically meaningful outcomes.

[Analysis of clinical features and etiological diagnostic indices of reproductive age women with hyperandrogenism]

Objective: To investigate the clinical features and the value of different diagnostic indices for etiology in reproductive age women with hyperandrogenism. Methods: The medical records of 96 reproductive age women with hyperandrogenism in the multi-disciplinary team of Peking University First Hospital from January 2020 to April 2021 were collected. The patients were divided into four groups based on final diagnosis: congenital adrenal hyperplasia (CAH) (n=8), polycystic ovary syndrome (PCOS) (n=67), idiopathic hyperandrogenism (n=13) and other specific diseases (n=8), respectively. The indices related to androgens in different groups were compared, and then their efficiency for diagnosis of CAH and PCOS were analyzed with receiver operator characteristic curve (ROC curve). Results: A total of 96 patients with hyperandrogenism were recruited, with the age of 19-45 (29±6) years old. Overall, 4.2% (4/96) of the patients were with single clinical hyperandrogenism, 56.3% (54/96) were with single laboratory hyperandrogenaemia and 39.6% (38/96) were with both. The breakdown into laboratory hyperandrogenaemia subtypes was as follows: only T elevation 22.8% (21/92), only A2 elevation 7.6% (7/92), none DHEAS elevation, only FAI elevation 5.4% (5/92) and elevation of more than one of the androgen indices mentioned above accounted for 64.1% (59/92). In the reasons of consultation, simple irregular menstruation (36.0%, 32/89) or accompanied by clinical hyperandrogenism with or without infertility (36.0%, 32/89) were the most common. As for primary visiting departments, Obstetrics and Gynecology accounted for 53.2% (51/96), and then Endocrinology as 39.5% (38/96). The 17-OHP level of CAH, PCOS and idiopathic hyperandrogenism group was 20.0 (8.2, 33.1), 1.1 (0.8, 1.4), 0.9 (0.8, 1.3) ng/ml, respectively. The androstenedione level in these groups was 6.3 (4.6, 8.7), 3.8 (2.9, 4.8) and 3.2 (2.7, 3.7) ng/ml, respectively. The 17-OHP and androstenedione levels of CAH group were significantly higher than that in PCOS or idiopathic hyperandrogenism group (all P<0.05). The ratio of LH and FSH in these three groups was 0.8(0.5, 1.0), 1.3(0.6, 1.9) and 0.6(0.3, 0.7), respectively. The ratio of LH and FSH was significantly higher in PCOS than that in idiopathic hyperandrogenism group (P=0.024), but yet there was no significant difference compared with CAH group (P>0.05). The AUC of ROC curve of 17-OHP for CAH diagnosis was 0.94, followed by androstenedione 0.83, whereas LH/FSH for PCOS diagnosis was only 0.63. Conclusions: Among the reasons of consultation in reproductive age women who visited our multi-disciplinary team for female hyperandrogenism, simple irregular menstruation or accompanied by clinical hyperandrogenism with or without infertility are the most common. PCOS accounts for the majority of different androgen excess disorders. 17-OHP is the most valuable parameter for the diagnosis of CAH and secondly androstenedione.

Lactobacillus crispatus DSM25988 as novel bioactive agent to co-aggregate Streptococcus pyogenes and to exclude it by binding to human cells

Streptococcus pyogenes, a group A streptococcus, is the major bacterial pathogen responsible for acute bacterial infection of the human oropharynx and the causative agent of scarlet fever. Estimates of the global burden of S. pyogenes related diseases revealed 616 million cases of pharyngitis, and at least 517,000 deaths due to severe invasive diseases and sequelae. Here we describe Lactobacillus crispatus DSM25988 that was identified among hundreds of Lactobacillus strains (referring to all organisms that were classified as Lactobacillaceae until 2020) showing ability to prevent adhesion of S. pyogenes to Detroit 562 cells, and to exhibit a masking and co-aggregating effect on S. pyogenes in vitro. L. crispatus DSM25988 also inhibits invasion of cultured human epithelial pharyngeal cells by S. pyogenes. Competitive binding to fibronectin might be involved in the inhibition process. Antiviral activity of the L. crispatus DSM25988 cells were identified in an in vitro cell model demonstrating that L. crispatus effectively excludes viruses from epithelial cells using SARS-CoV2 proteins as a model. This finding points to the potential of DSM25988 to protect cells from virus infection. Biological activity is retained in heat treated cells. The heat-treated Lactobacillus strain was further developed into functional throat lozenges, wherein its biological activity is stably maintained in the formulation. Lozenges containing L. crispatus DSM25988 underwent testing in an uncontrolled, prospective user study in 44 subjects with symptoms of sore throat for a period of up to 14 days. The study data shows promising safety and efficacy of the medical device when used against symptoms of sore throat like scratchy feeling, hoarse voice and swallowing pain.

PSXVI-26 Using synchrotron/globar techniques to reveal synergistic and interactive association between molecular structures and nutrient supply in enzymatic and thermal treated oat tissue and whole grain

As an advanced technique, synchrotron radiation-based microspectroscopy SR-FTIRM has been a rapid, direct, non-destructive and non-invasive bioanalytical method. Globar molecular spectroscopic technique -attenuated total reflectance-ATR-FTIR spectroscopy will be used. For this research, feed type CDC Nasser, forage type CDC haymaker, and milling types CDC Arborg and Summit with three consecutive years are studied. There are three treatments for oat samples: Treatment 1, steam pressure processing alone; Treatment 2, adding innovative fibrolytic enzyme; Treatment 3, steam pressure processing plus fibrolytic enzyme. Each treatment combination has three replications. The objectives of this research are to detect the molecular structure spectral features of processed oat endosperm tissues at a molecular and cellular level in relation to chemical profiles, protein and carbohydrate fractions, energy profiles, degradation kinetics, intestinal digestibility, microbial protein production and true nutrient supply of whole oat grains. This research reveals the interactive association between induced molecular structure changes and nutrient properties and true nutrient supply. This research is also to increase economic returns to oat producers and related dairy industries through efficient utilization of feed-type or milling type of oat grains.

Dapagliflozin improves left ventricular myocardial longitudinal function in people with type 2 diabetes

Background/Introduction

Asymptomatic left ventricular (LV) dysfunction is highly prevalent in patients with type 2 diabetes mellitus (T2DM). Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been shown to reduce all-cause mortality and hospitalisations for heart failure in patients with T2DM. The underlying mechanisms for these cardiovascular benefits are unclear. In the Dapa-LVH trial, we had previously shown that dapagliflozin treatment significantly reduces LV mass (LVM) compared to placebo in patients with T2DM and LV hypertrophy (LVH).

Purpose

The objective of this sub-study of the Dapa-LVH study was to assess whether dapagliflozin treatment improves LV myocardial longitudinal function and LV diastolic function in patients with T2DM and LVH.

Methods

We randomly assigned 66 people (mean age 67±7 years, 38 males) with T2D, LVH with a normal LV ejection fraction to receive dapagliflozin 10mg once-daily or placebo for 12 months. The primary endpoints were change in global longitudinal strain (GLS) and LV diastolic function defined as the ratio of mitral inflow E to mitral e' annual velocities assessed using echocardiography. Secondary endpoints were left ventricular and atrial volumes assessed using cardiac magnetic resonance.

Results

Dapagliflozin treatment resulted in a median increase in GLS of −1.64±2.5% vs placebo −0.2±1.8; p=0.024, with a mean difference of −1.4% (95% CI: −2.7 to −0.2). There was a trend towards a reduction left atrial area with a median change in left atrial area of the dapagliflozin group −0.5±3.75 cm2 vs placebo group 0.0±3.5 cm2; p=0.088), leading to an absolute mean difference of −1.29cm2 (95% CI: −3.01 to 0.44). There was no significant difference between dapagliflozin and placebo in E/e' and in LV volumes.

Conclusion

Dapagliflozin treatment improved LV myocardial longitudinal function which may suggests it may improve subclinical LV dysfunction.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): This study was funded by an Externally Sponsored Research grant from Astra Zeneca – (grant number ESR-14-10168

Feasibility of markerless fluoroscopic real-time tumor detection for adaptive radiotherapy: development and end-to-end testing

Respiratory-gated radiotherapy treatments of lung tumors reduce the irradiated normal tissue volume and potentially lower the risk of side effects. However, in clinical routine, the gating signal is usually derived from external markers or other surrogate signals and may not always correlate well with the actual tumor position. This study uses the kV-imaging system of a LINAC in combination with a multiple template matching algorithm for markerless real-time detection of the tumor position in a dynamic anthropomorphic porcine lung phantom. The tumor was realized by a small container filled with polymer dosimetry gel, the so-called gel tumor. A full end-to-end test for a gated treatment was performed and the geometric and dosimetric accuracy was validated. The accuracy of the tumor detection algorithm in SI- direction was found to be [Formula: see text] mm and the gel tumor was automatically detected in 98 out of 100 images. The measured 3D dose distribution showed a uniform coverage of the gel tumor and comparison with the treatment plan revealed a high 3D [Formula: see text]-passing rate of [Formula: see text] ([Formula: see text]). The simulated treatment confirmed the employed margin sizes for residual motion within the gating window and serves as an end-to-end test for a gated treatment based on a markerless fluoroscopic real-time tumor detection.

Using big data to explore worldwide trends in objective sleep in the transition to adulthood

BACKGROUND

Development induces changes in sleep, and its duration has been reported to change as a function of aging. Additionally, sleep timing is a marker of pubertal maturation, where during adolescence, the circadian rhythm shifts later. Typically, this is manifested in a later sleep onset in the evening and later awakening in the morning. These changes across development seem to be universal around the world but are unlikely to persist into adulthood.

METHODS

This study utilized accelerometer data from 17,355 participants aged 16-30 years (56% female) measured by validated Polar wearables over a 14-day period. We compared sleep duration, chronotype (sleep midpoint) and weekend catch-up (ie, social jetlag) sleep across ages and regions over 242,948 nights.

RESULTS

The data indicate a decline in sleep duration as well as a dramatic shift in sleep onset times throughout adolescence. This continues well into early adulthood and stabilizes nearer age 30. Differences in sleep duration across ages were significant, and ranged from 7:53 h at age 16 to 7:29 h at age 30 in the sample. Additionally, there was a clear difference between females and males throughout adolescence and young adulthood: girls had longer sleep duration and earlier timed sleep in the current study. Differences in sleep were found between regions across the world, and across European areas.

CONCLUSIONS

Both sleep duration and sleep timing go through a clear developmental pattern, particularly in early adulthood. Females had an earlier sleep midpoint and obtained more sleep. Regional differences in sleep occurred across the world.

Quantum interface of an electron and a nuclear ensemble

Coherent excitation of an ensemble of quantum objects underpins quantum many-body phenomena and offers the opportunity to realize a memory that stores quantum information. Thus far, a deterministic and coherent interface between a spin qubit and such an ensemble has remained elusive. In this study, we first used an electron to cool the mesoscopic nuclear spin ensemble of a semiconductor quantum dot to the nuclear sideband–resolved regime. We then implemented an all-optical approach to access individual quantized electronic-nuclear spin transitions. Lastly, we performed coherent optical rotations of a single collective nuclear spin excitation—a spin wave. These results constitute the building blocks of a dedicated local memory per quantum-dot spin qubit and promise a solid-state platform for quantum-state engineering of isolated many-body systems.

Feasibility of polymer gel-based measurements of radiation isocenter accuracy in magnetic fields

For conventional irradiation devices, the radiation isocenter accuracy is determined by star shot measurements on films. In magnetic resonance (MR)-guided radiotherapy devices, the results of this test may be altered by the magnetic field and the need to align the radiation and imaging isocenter may require a modification of measurement procedures. Polymer dosimetry gels (PG) may offer a way to perform both, the radiation and imaging isocenter test, however, first it has to be shown that PG reveal results comparable to the conventionally applied films. Therefore, star shot measurements were performed at a linear accelerator using PG as well as radiochromic films. PG were evaluated using MR imaging and the isocircle radius and the distance between the isocircle center and the room isocenter were determined. Two different types of experiments were performed: i) a standard star-shot isocenter test and (ii) a star shot, where the detectors were placed between the pole shoes of an experimental electro magnet operated either at 0 T or 1 T. For the standard star shot, PG evaluation was independent of the time delay after irradiation (1 h, 24 h, 48 h and 216 h) and the results were comparable to those of film measurements. Within the electro magnet, the isocircle radius increased from 0.39  ±  0.01 mm to 1.37  ±  0.01 mm for the film and from 0.44  ±  0.02 mm to 0.97  ±  0.02 mm for the PG-measurements, respectively. The isocenter distance was essentially dependent on the alignment of the magnet to the isocenter and was between 0.12  ±  0.02 mm and 0.82  ±  0.02 mm. The study demonstrates that evaluation of the PG directly after irradiation is feasible, if only geometrical parameters are of interest. This allows using PG for star shot measurements to evaluate the radiation isocenter accuracy with comparable accuracy as with radiochromic films.

Replacement, Reduction, Refinement - Animal welfare progress in European Pharmacopoeia monographs: activities of the European Pharmacopoeia Commission from 2007 to 2017

Since the opening for signature of the European Convention for the Protection of Animals Used for Experimental and Other Scientific Purposes in 1986, the European Pharmacopoeia Commission and its experts have carried out a programme of work committed to Replacing, Reducing and Refining (3Rs) the use of animals for test purposes. While updates on achievements in the field of the 3Rs are regularly provided, this article summarises the activities of the Ph. Eur. Commission in this field within the last decade.

Familial hypercholesterolaemia in patients with ischaemic stroke or transient ischaemic attack

BACKGROUND AND PURPOSE

Identification of patients with familial hypercholesterolaemia (FH) is a prerequisite for the appropriate management of their excess cardiovascular risk. It is currently unknown how many patients with acute ischaemic stroke or transient ischaemic attack (TIA) are affected by FH and whether systematic screening for FH is warranted in these patients.

METHODS

The prevalence of a clinical diagnosis of FH was estimated in a large representative series of patients with acute ischaemic stroke or TIA (ABCD2 score ≥ 3) using the Dutch Lipid Clinic Network Algorithm (DLCNA; possible FH ≥3, probable/definite FH ≥6).

RESULTS

Out of 1054 patients included in the present analysis, 14 had probable/definite FH (1.3%; 95% confidence interval 0.6-2.0) and 107 possible FH (10.2%; 8.4-12.0) corresponding to an overall prevalence of potential FH of 11.5%. Prevalences were even higher in patients with stroke/TIA manifestation before age 55 in men or 60 in women (3.1%, 0.6-5.6; and 13.1%, 8.3-17.9) and those with a prior history of cardiovascular disease (2.6%, 0.9-4.3; and 15.1%, 11.3-18.9). Of note, in two-thirds of our patients with probable/definite and possible FH, stroke or TIA was the initial clinical disease manifestation.

CONCLUSIONS

The frequency of potential FH, based on clinical criteria, in patients with acute ischaemic stroke or TIA was 11.5% and that of probable/definite FH (1.3%) was similar to recently reported counts for patients with acute coronary syndrome (1.6%). FH screening using the DLCNA is feasible in clinical routine and should be considered as part of the usual diagnostic work-up.

When is a terrace not a terrace? The importance of understanding landscape evolution in studies of terraced agriculture

Before the invention of modern, large-scale engineering projects, terrace systems were rarely built in single phases of construction, but instead developed gradually, and could even be said to have evolved. Understanding this process of landscape change is therefore important in order to fully appreciate how terrace systems were built and functioned, and is also pivotal to understanding how the communities that farmed these systems responded to changes; whether these are changes to the landscape brought about by the farming practices themselves, or changes to social, economic or climatic conditions. Combining archaeological stratigraphy, soil micromorphology and geochemistry, this paper presents a case-study from the historic and extensive terraced landscape at Konso, southwest Ethiopia, and demonstrates - in one important river valley at least - that the original topsoil and much of the subsoil was lost prior to the construction of hillside terraces. Moreover, the study shows that alluvial sediment traps that were built adjacent to rivers relied on widespread hillside soil erosion for their construction, and strongly suggests that these irrigated riverside fields were formerly a higher economic priority than the hillside terraces themselves; a possibility that was not recognised by numerous observational studies of farming in this landscape. Research that takes into account how terrace systems change through time can thus provide important details of whether the function of the system has changed, and can help assess how the legacies of former practices impact current or future cultivation.

Novel bioactive from Lactobacillus brevis DSM17250 to stimulate the growth of Staphylococcus epidermidis: a pilot study

Commensal skin microbiota plays an important role in both influencing the immune response of the skin and acting as a barrier against colonisation of potentially pathogenic microorganisms and overgrowth of opportunistic pathogens. Staphylococcus epidermidis is a key constituent of the normal microbiota on human skin. It balances the inflammatory response after skin injury and produces antimicrobial molecules that selectively inhibit skin pathogens. Here we describe Lactobacillus brevis DSM17250 that was identified among hundreds of Lactobacillus strains to exhibit an anti-inflammatory effect in human keratinocytes in vitro and specific stimulatory impact on the growth of S. epidermidis. The aqueous cell-free extract of L. brevis DSM17250 was used in an ointment formulation and tested in a randomized placebo-controlled double blinded human pilot study. Healthy volunteers with diagnosed dry skin were treated for four weeks. The study data shows that L. brevis DSM17250 extract induces re-colonisation of the skin by protective commensal microorganisms as judged from selective bacterial cultivation of surface-associated skin microorganism of the lower leg. Furthermore, the 4 week administration of the L. brevis DSM17250 extract significantly improved the transepidermal water loss value (TEWL), reduced the xerosis cutis symptoms and stinging. The data shows that daily application of L. brevis DSM17250 extract in a topical product significantly improves the microbial skin microbiota by promoting the growth of species which possess beneficial regulatory and protective properties such as S. epidermidis. Restoring the natural skin microbiota leads to significantly improved skin barrier function (as transepidermal water loss) and decrease of xeroderma (xerosis cutis) symptoms (as measured by dry skin area and severity index, DASI). We propose that improving and stabilizing the natural skin microbiota by specifically stimulating the growth of S. epidermidis is an important and novel concept to manage skin diseases associated with microbiota dysbiosis.

An electrochemical platform for localized pH control on demand

Solution pH is a powerful tool for regulating many kinds of chemical activity, but is generally treated as a static property defined by a pre-selected buffer. Introducing dynamic control of pH in space, time, and magnitude can enable richer and more efficient chemistries, but is not feasible with traditional methods of titration or buffer exchange. Recent reports have featured electrochemical strategies for modifying bulk pH in constrained volumes, but only demonstrate switching between two preset values and omit spatial control entirely. Here, we use a combination of solution-borne quinones and galvanostatic excitation to enable quantitative control of pH environments that are highly localized to an electrode surface. We demonstrate highly reproducible acidification and alkalinization with up to 0.1 pH s(-1) (±0.002 pH s(-1)) rate of change across the dynamic range of our pH sensor (pH 4.5 to 7.5) in buffered solutions. Using dynamic current control, we generate and sustain 3 distinct pH microenvironments simultaneously to within ±0.04 pH for 13 minutes in a single solution, and we leverage these microenvironments to demonstrate spatially-resolved, pH-driven control of enzymatic activity. In addition to straightforward applications of spatio-temporal pH control (e.g. efficiently studying pH-dependencies of chemical interactions), the technique opens completely new avenues for implementing complex systems through dynamic control of enzyme activation, protein binding affinity, chemical reactivity, chemical release, molecular self-assembly, and many more pH-controlled processes.

Tyrothricin--An underrated agent for the treatment of bacterial skin infections and superficial wounds?

The antimicrobial agent tyrothricin is a representative of the group of antimicrobial peptides (AMP). It is produced by Bacillus brevis and consists of tyrocidines and gramicidins. The compound mixture shows activity against bacteria, fungi and some viruses. A very interesting feature of AMPs is the fact, that even in vitro it is almost impossible to induce resistances. Therefore, this class of molecules is discussed as one group that could serve as next generation antibiotics and overcome the increasing problem of bacterial resistances. In daily practice, the application of tyrothricin containing formulations is relatively limited: It is used in sore throat medications and in agents for the healing of infected superficial and small-area wounds. However, due to the broad spectrum antimicrobial activity and the low risk of resistance development it is worth to consider further fields of application.