A versatile SERS platform based on conductive MOF-enforced carbon paper for rapidly and sensitively monitoring diazepam in aquatic products

Herein, a versatile surface enhanced Raman scattering (SERS) platform was firstly constructed by integrating conductive metal organic framework (CMOF) with controlled electrodeposition of Au nanoparticles (Au NPs) on flexible carbon paper (CP-CMOF@Au) for sensitively recognizing diazepam (DZP) in aquatic products. The CMOF not only provided a pre-concentration effect for boosting sensitivity, but also dramatically improved the intrinsic electrical conductivity contributing to homogeneous distribution of Au NPs and forming SERS-active "hot spot" with superior stability and reproducibility. Based on CP-CMOF@Au chip, DZP can be sensitively detected with low limit of detection of 0.64 ng mL-1 and wide linear detection range from 0.001 to 10 μg mL-1. Also, DZP in aquatic products can be collected and recognized using multiple approaches (drip coating, soaking and wiping) with excellent reusability and satisfactory recovery of 85.8-103.3%. This method would provide an ingenious SERS strategy for rapidly monitoring DZP in aquatic products with good practical applicability.

Axially Coordinated Gold Nanoclusters Tailoring Fe-N-C Nanozymes for Enhanced Oxidase-Like Specificity and Activity

Metal-organic frameworks (MOF) derived nitrogen-doped carbon-supported monodisperse Fe (Fe-N-C) catalysts are intensively studied, but great challenges remain in understanding the relationship between the coordination structure and the performance of Fe-N-C nanozymes. Herein, a novel nanocluster ligand-bridging strategy is proposed for constructing Fe-S1 N4 structures with axially coordinated S and Au nanoclusters on ZIF-8 derived Fe-N-C (labeled Aux /Fe-S1 N4 -C). The axial Au nanoclusters facilitate electron transfer to Fe active sites, utilizing the bridging ligand S as a medium, thereby enhancing the oxygen adsorption capacity of composite nanozymes. Compared to Fe-N-C, Aux /Fe-S1 N4 -C exhibits high oxidase-like specificity and activity, and holds great potential for detecting acetylcholinesterase activity with a detection limit of 5.1 µU mL-1 , surpassing most reported nanozymes.

Interface thermal conductivities induced by van der Waals interactions

The interface heat transfer of two layers induced by van der Waals (vdW) contacts is theoretically investigated, based on first-principles calculations at low temperatures. The results suggest that out-of-plane acoustic phonons with low frequencies dominate the interface thermal transport due to the vdW interaction. The interface thermal conductivity is proportional to the cubic of temperature at very low temperatures, but becomes linearly proportional to temperature as temperature increases. We show that manipulating the strain alters vdW coupling, leading to increased interfacial thermal conductivity at the interface. Our findings provide valuable insights into the interface heat transport in vdW heterostructures and support further design and optimization of electronic and optoelectronic nanodevices based on vdW contacts.

Reconnection of cysteine in reduced hair with alkylene dimaleates via thiol-Michael click chemistry

OBJECTIVES

Conventional hair permanent waving (PW) and permanent straightening processes typically involve two steps: reduction, for breaking -S-S- bond in cystine into cysteine and oxidation for -S-S- bond reconnection. However, it is known that the hair incurs damage during the oxidation step. In this work, we proposed a novel strategy to reconnect reduced disulfide bonds in hair via the thiol-Michael click reaction, by using a symmetric Michael reagent.

METHODS

Virgin black Chinese hair was reduced using 8% wt thioglycolic acid and employed as model hair containing a high content of broken disulfide bonds. The reduced hair was treated with 1,4-n-butylene dimaleate. Raman spectroscopy and Fourier transform infrared spectroscopy (FT-IR) were used to verify the chemical changes occurred in untreated and treated hair fibre. Single-fibre mechanical properties and thermal properties of the hair were evaluated using tensile testing and differential scanning calorimetry (DSC), respectively.

RESULTS

The 1,4-n-butylene dimaleate could reconnect free thiol groups generated by disulfide bond reduction via thiol-Michael click reaction and significantly improve the mechanical strength of hair compared to that of the reduced hair. Secondary conformational resolution analysis of FT-IR results revealed that the content of α-helix structure could be restored after treatment with 1,4-n-butylene dimaleate. The intermolecular forces established by the newly generated C-S bonds compensate the broken disulfide bonds and enhance the fracture strength of the hair compared to that of reduced hair. Michael reagents of similar structure also showed similar performance in restoring the mechanical properties of reduced hair.

CONCLUSIONS

Our data suggest that 1,4-n-butylene dimaleate can restore the mechanical properties of reduced hair by reconnecting reduced disulfide bonds and restoring the secondary conformation of hair keratin.

Cation-Radius-Controlled Sn-O Bond Length Boosting CO2 Electroreduction over Sn-Based Perovskite Oxides

Despite the intriguing potential shown by Sn-based perovskite oxides in CO2 electroreduction (CO2 RR), the rational optimization of their CO2 RR properties is still lacking. Here we report an effective strategy to promote CO2 -to-HCOOH conversion of Sn-based perovskite oxides by A-site-radius-controlled Sn-O bond lengths. For the proof-of-concept examples of Ba1-x Srx SnO3 , as the A-site cation average radii decrease from 1.61 to 1.44 Å, their Sn-O bonds are precisely shortened from 2.06 to 2.02 Å. Our CO2 RR measurements show that the activity and selectivity of these samples for HCOOH production exhibit volcano-type trends with the Sn-O bond lengths. Among these samples, the Ba0.5 Sr0.5 SnO3 features the optimal activity (753.6 mA ⋅ cm-2 ) and selectivity (90.9 %) for HCOOH, better than those of the reported Sn-based oxides. Such optimized CO2 RR properties could be attributed to favorable merits conferred by the precisely controlled Sn-O bond lengths, e.g., the regulated band center, modulated adsorption/activation of intermediates, and reduced energy barrier for *OCHO formation. This work brings a new avenue for rational design of advanced Sn-based perovskite oxides toward CO2 RR.

Tuning nano-skyrmions and nano-skyrmioniums in Janus magnets

We study non-trivial spin textures, nanoscale magnetic skyrmions and skyrmioniums, in two-dimensional (2D) Janus magnets, such as MnSTe and MnSeTe, based on the micromagnetism approach and Landau-Lifshitz-Gilbert (LLG) equation. It is found that the Janus magnetic structures can host stable Néel nano-skyrmions with sub-10 nm diameters, and skyrmioniums with zero topological charge. The skyrmion size can be squeezed by external magnetic fields, and even the topological charge can be changed. The diameters of the skyrmioniums are about twice the size of the skyrmions. Moreover, the switching of the topological charge Q = ±1 can be realized by changing the direction of the external magnetic fields. Our results clearly show that magnetic skyrmions in Janus magnets can be used to construct new types of efficient spintronic nanodevices.

Phosphine-based metal-organic layers to construct single-site heterogeneous catalysts for arene borylation

Metal-organic layers (MOLs) are versatile platforms for creating single-site heterogeneous catalysts. Incorporating molecular functionalities into MOLs is crucial for catalysis. In this study, we synthesized phosphine-containing MOLs constructed from Hf₆-oxo secondary building units (SBUs) and phosphine ligands. The mono(phosphine)-Ir complexes generated by the metalation of TPP-MOL were highly active as heterogeneous catalysts for the C(sp²)-H borylation of a range of arenes. This research expands the diversity of MOL-based catalysts.

Sophorolipid inhibits histamine-induced itch by decreasing PLC/IP3R signaling pathway activation and modulating TRPV1 activity

Biosurfactants are attracting much interest due to their potential application as therapeutic agents in the medical and cosmetic field. Previous studies have demonstrated that biosurfactant such as sophorolipid (SL) exhibits immunomodulatory effects. In this article, we found the potential of sophorolipid for inhibiting histamine-induced itch and preliminarily explored its molecular basis. First, behavioral tests indicated that SL can remit the histamine-induced scratching behaviors of mice. Second, SL can suppress the the calcium influx induced by histamine, HTMT and VUF8430 in HaCaT cells. RT-PCR analysis showed that the histamine-induced upregulation of mRNA levels of phospholipase Cγ1, 1,4,5-trisphosphate receptor (IP3R), and protein kinase Cα can be inhibted by SL, suggesting that SL may impede the PLC/IP3R signaling pathway activated by histamine. In further tests, the capsaicin-induced calcium influx can also be inhibited by SL. The immunofluorescence and molecular docking analysis indicated that SL acts as an inhibitor of transient receptor potential vanilloid-1 (TRPV1) activation to decrease calcium influx against stimuli. In summary, these results revealed that SL may inhibit histamine-induced itch by decreasing PLC/IP3R signaling pathway activation and modulating TRPV1 activity. This paper indicates that SL can be a useful treatment for histamine-dependent itch.

Accelerated Water Oxidation Kinetics Triggered by Supramolecular Porphyrin Nanosheet for Robust Visible-Light-Driven CO2 Reduction

Water oxidation is one of the most challenging steps in CO₂ photoreduction, but its influence on CO₂ photoreduction is still poorly understood. Herein, the concept of accelerating the water oxidation kinetics to promote the CO₂ photoreduction is realized by incorporating supramolecular porphyrin nanosheets (NS) into the C₃ N₄ catalyst. As a prototype, porphyrin-C₃ N₄ based van der Waals heterojunctions with efficient charge separation are elaborately designed, in which the porphyrin and C₃ N₄ NS serve as the water oxidation booster and CO₂ reduction center, respectively. Theoretical calculations and relevant experiments demonstrate that the added porphyrin NS reverses the rate-limiting step in the water oxidation while reducing its energy barrier, thus resulting in faster reaction kinetics. Therefore, the optimal sample shows excellent performance in visible-light-driven CO₂ reduction with a maximum CO evolution rate of 16.8 µmol g^-1 h^-1 , which is 6.8 times that of the C₃ N₄ NS and reaches the current state of the art for C₃ N₄ -based materials in CO₂ photoreduction. Overall, this work throws light that accelerating water oxidation kinetics can effectively improve the CO₂ photoreduction efficiency.

Polarization due to emergent polarity in elemental semiconductor thinfilms under bending

Polarization via strain engineering provides a facial way to functionalize materials. We investigate the origin of electronic polarization in the bent elemental semiconductor thinfilms by combining analytical modeling with quantum mechanical simulation. A bond orbital model reveals a polarity of covalent bonds induced by strain gradient such that polarization along the strain gradient dimension can be induced, giving rise to the flexoelectric effect. At strain gradient1/R=0.01 nm^-1, the net charge differences between the two sides are5×10-4e,2.5×10-3eand7.2×10-3efor C, Si and Ge films respectively. On the other hand, due to the emergent bond polarity, the polarization can be effectively tuned by normal strain applied to the bent film, mimicking the piezoelectric effect. Simulations using the generalized Bloch theorem strongly support this revelation. Findings have important implications for delineating the formation of polarization and related phenomena in semiconductors.

The ultra-processed food content of school meals and packed lunches in the United Kingdom (2008-2017)

Background

British children have the highest ultra-processed food (UPF) intake in Europe, which is linked to adverse health outcomes. Schools are posited as a setting for dietary intervention, yet the level of UPFs consumed at schools is currently unknown. This study aimed to describe the UPF content of school food in the UK, explore the UPF content of school meals and packed lunches (food from home) and examine whether UPF differs by children's household income.

Methods

A pooled cross-sectional analysis of primary (4-11 years, n = 1,895) and secondary schoolchildren (11-18 years, n = 1,408) from the UK's National Diet and Nutrition Survey (2008-2017) was conducted. Food diaries recorded student's meal-type (school meal/packed lunch). UPF intake was defined using the NOVA food classification system. Quantile regression models assessed the association between meal-type and lunchtime UPF intake (%kcal and % grams). Models were stratified by school phase (primary/secondary) and interacted meal-type with income.

Results

Schoolchildren consumed most of their lunch as UPF, with higher median intakes in secondary schoolchildren than primary schoolchildren (77.8 %kcal vs 72.6 %kcal). School meals were associated with lower median UPF intake (%kcal) in both primary (-20 percentage-points[pp] [95% CI -22.2, -17.4]) and secondary schoolchildren (-11pp [-16.0,-7.0]) compared with packed lunches. Results were similar when UPF %g was analysed. Overall, income was inversely associated with UPF content. However, in primary schoolchildren there was no significant income gradient in the UPF(%g) content of school meals.

Conclusions

In the first nationally representative study, we showed that on average UPF intake was high in all UK schoolchildren. Higher UPF intakes were observed in packed lunch consumers, secondary schoolchildren, and those with a lower income. Procurement policies must be revaluated to protect children from high UPF intake.

Funders: NIHR School for Public Health Research

Key messages

• In the first study of ultra-processed food content of UK school food, we show that children consumed around three quarters of their energy as ultra-processed food at lunch.

• Children who were older, took food from home or were from a low-income household were more likely to consume higher levels of ultra-processed food. Regulation is needed to protect these children.

Global market trends of flavour capsule and menthol cigarettes in 78 countries, 2010-2020

Background

Flavoured tobacco products, including innovative flavour capsule cigarettes (FCCs) and menthol cigarettes, can increase appeal and encourage smoking initiation and use. Global epidemiological data on these products are scarce.

Methods

This study examined market trends of FCCs and menthol (non-capsule) cigarettes across 78 countries from 2010 to 2020 and assessed ecological-level factors associated with market shares of these products. Market share and retail volume data came from Euromonitor Passport and country-specific sociodemographic data come from the WHO and World Bank. Adjusted linear fixed effects panel regression analyses were used to evaluate the relationship between predictors variables and market outcomes.

Results

Global total retail volume of FCCs increased over time (0.2% in 2010 to 4.5% in 2020) and market share was associated with year and unemployment rate and inversely associated with % urban population and smoking prevalence (p < 0.001). In contrast, menthol retail volume decreased over time (5.0% to 3.8%) and market share was associated with % urban population (p = 0.001) and inversely associated with year (p = 0.004) and unemployment rate (p = 0.017). The greatest market increase of FCCs was observed in the Americas region and among upper-middle income countries. In Europe, there was a decrease of 0.64 percentage points from 2019 to 2020.

Conclusions

Overall, FCCs experienced substantial global growth in the recent decade, with the exception of Europe whose slight decrease may be attributable to the European Union ban on flavours in cigarettes. Findings indicate that there is a need for increased efforts to address flavours and innovative features used in tobacco products, which are known to appeal to youth.

Key messages

• This study contributes to global monitoring of tobacco products.

• Findings can be used by advocates and policy makers to support countries in adopting measures to ban flavoured tobacco products.

NLRP3 rs1539019 is significantly associated with chronic obstructive pulmonary disease in a Chinese Han population: a case-control study

OBJECTIVE

COPD is a complex respiratory disease characterized by chronic airway inflammation and the airflow limitations are not fully reversible due to the combination of genetic and environmental factors. Genetic factors such as polymorphisms, may affect the susceptibility of COPD. In the present study, we examined the association between the polymorphisms of three genes and COPD risk in a Chinese Han population.

PATIENTS AND METHODS

A total of 375 COPD patients and 284 control subjects were recruited from November 2018 to June 2021. Data on demographic basic information, smoking status, history of coal dust exposure, and peripheral blood were collected from subjects of two groups. Three polymorphisms (NLRP3 rs1539019, LAMB1 rs4320486,  IL-6 rs1800796) were analyzed. Logistic analysis was used to evaluate the genetic contribution of selected SNPs to COPD susceptibility.

RESULTS

The AC genotype of NLRP3 rs1539019 significantly decreased COPD risk compared with CC genotype (adjusted OR = 0.508, 95% CI 0.336-0.767). In the stratification analyses, the AC genotype significantly decreased the risk of COPD in subjects aged 60 and over (p=0.005; adjusted OR = 0.553; 95% CI 0.366-0.835) with current smoking status (p=0.002; adjusted OR = 0.419; 95% CI 0.240-0.732) when compared with AA+CC genotype. Moreover, a significantly decreased risk for GOLD III COPD was found in genotype AC of NLRP3 rs1539019 (p=0.006; adjusted OR = 0.502; 95% CI 0.306-0.822).

CONCLUSIONS

Our present study revealed that the genotype AC of NLRP3 rs1539019 is related to a decreased risk of COPD in a Chinese Han population, a large-sample, multi-center, multi-ethnic study is needed to further confirm our study.

Radiomics-Based Machine Learning for Outcome Prediction in a Multicenter Phase II Study of Programmed Death-Ligand 1 Inhibition Immunotherapy for Glioblastoma

BACKGROUND AND PURPOSE

Imaging assessment of an immunotherapy response in glioblastoma is challenging due to overlap in the appearance of treatment-related changes with tumor progression. Our purpose was to determine whether MR imaging radiomics-based machine learning can predict progression-free survival and overall survival in patients with glioblastoma on programmed death-ligand 1 inhibition immunotherapy.

MATERIALS AND METHODS

Post hoc analysis was performed of a multicenter trial on the efficacy of durvalumab in glioblastoma (n = 113). Radiomics tumor features on pretreatment and first on-treatment time point MR imaging were extracted. The random survival forest algorithm was applied to clinical and radiomics features from pretreatment and first on-treatment MR imaging from a subset of trial sites (n = 60-74) to train a model to predict long overall survival and progression-free survival and was tested externally on data from the remaining sites (n = 29-43). Model performance was assessed using the concordance index and dynamic area under the curve from different time points.

RESULTS

The mean age was 55.2 (SD, 11.5) years, and 69% of patients were male. Pretreatment MR imaging features had a poor predictive value for overall survival and progression-free survival (concordance index  = 0.472-0.524). First on-treatment MR imaging features had high predictive value for overall survival (concordance index = 0.692-0.750) and progression-free survival (concordance index = 0.680-0.715).

CONCLUSIONS

A radiomics-based machine learning model from first on-treatment MR imaging predicts survival in patients with glioblastoma on programmed death-ligand 1 inhibition immunotherapy.

Small Fiber Neuropathy

PURPOSE OF REVIEW

This narrative review aims to summarize advances in the field of small fiber neuropathy made over the last decade, with emphasis on novel research highlighting the distinctive features of SFN.

RECENT FINDINGS

While the management of SFNs is ideally aimed at treating the underlying cause, most patients will require pain control via multiple, concurrent therapies. Herein, we highlight the most up-to-date information for diagnosis, medication management, interventional management, and novel therapies on the horizon. Despite the prevalence of small fiber neuropathies, there is no clear consensus on guidelines specific for the treatment of SFN. Despite the lack of specific guidelines for SFN treatment, the most recent general neuropathic pain guidelines are based on Cochrane studies and randomized controlled trials (RCTs) which have individually examined therapies used for the more commonly studied SFNs, such as painful diabetic neuropathy and HIV neuropathy. The recommendations from current guidelines are based on variables such as number needed to treat (NNT), safety, ease of use, and effect on quality of life.

Microplasma synthesized gold nanoparticles for surface enhanced Raman spectroscopic detection of methylene blue

Surface enhanced Raman scattering (SERS) is a powerful and sensitive spectroscopic technique that allows for rapid detection of trace-level chemical species in a non-invasive and non-destructive manner.

Childhood consumption of ultra-processed foods and adiposity trajectories: a UK birth cohort study

Background

Worldwide consumption of ultra-processed foods (UPFs) is continued to rise. Growing evidence has linked higher consumption with elevated risks of obesity and non-communicable diseases in adults. However, the influence of UPFs on long-term adiposity trajectories have not been evaluated in children.

Methods

Prospective birth cohort data were obtained from the Avon Longitudinal Study of Parents and Children. English children with baseline dietary intakes from 3-day food diaries and repeated adiposity measures were followed up from ages 7-24 years. Outcomes included body mass index (BMI), weight, waist circumference (WC), fat mass index (FMI) and body fat percentage. UPFs were identified using the NOVA food classification. Child's consumption of UPFs was derived as a percentage of its weight contribution (gram per day) in the total diet and categorised into quintiles. Longitudinal associations were assessed using linear growth curve models and adjusted for study covariates.

Results

Of the 9025 children followed up over a median (IQR) of 10.2 (5.2-16.4) years. Trajectories of BMI, FMI, weight and WC increased by an additional 0.06 (95% CI, 0.04-0.08) kg/m2, 0.03 (0.01-0.05) kg/m2, 0.20 (0.11-0.28) kg and 0.17 (0.11-0.22) cm per year among those in the highest (vs. lowest) quintile of UPF consumption. Evidence of dose-response relationships were consistently observed with those in the two highest quintiles of UPF consumption showing significantly more rapid progression of BMI, weight, and WC.

Conclusions

Radical and effective public health actions that reduce children's exposure and consumption of UPFs are urgently needed to address the obesity epidemic in England and internationally.

Funding: CM and EV are funded by the National Institute for Health Research (NIHR) School for Public Health Research (SPHR), Grant Reference Number PD-SPH-2015. The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care.

Key messages

Children with highest (vs. lowest) quintile of ultra-processed food consumption had more rapid regression of BMI, FMI, weight and waist circumference from ages 7-24 years. Dose-response relationships were consistently observed in the two highest quintile of ultra-processed food consumption showing more rapid progression of BMI, weight and waist circumference.

[Clinical features of primary isolated chylopericardium: a retrospective review study]

Objective: To examine the clinical characteristics and abnormal reflux branches of primary isolated chylopericardium. Methods: Totally 43 patients with primary isolated chylopericardium at Department of Lymphatic Surgery, Affiliated Beijing Shijitan Hospital,Capital Medical University from June 2007 to January 2018 were recruited in this study. There were 21 males and 22 females, aging (23.0±15.9) years (range: 2 to 57 years). The levels of triglyceride, total cholesterol, total protein and albumin in pericardial effusion and blood were compared by paired-t test, and the characteristics of lymphatic system in direct lymphangiography and postoperative CT were analyzed. Results: Pericardial effusion was mainly milky white and monocytes, and 95.3%(41/43) were positive for Rivalta test. The level of triglyceride in pericardial effusion was significantly higher than that of blood ((9.67±5.11) mmol/L vs. (1.28±0.89) mmol/L, t=10.557, P<0.01), and the levels of total cholesterol ((2.19±0.52) mmol/L vs. (4.12±1.06) mmol/L, t=-3.732, P<0.01), total protein ((61.25±16.17) g/L vs. (68.26±8.30) g/L, t=-2.958, P=0.005) and albumin ((36.63±7.06) g/L vs. (42.32±4.73) g/L, t=-5.747, P<0.01) were significantly lower than that of blood. In the direct lymphangiography, the imaging of iliac and retroperitoneal lymphatics showed dilated or tortuous in 90.7% (39/43), the thoracoabdominal segment of thoracic duct showed dilation in 46.5% (20/43), and cervical thoracic duct imaging showed dilation in 44.2% (19/43) and stenosis in 55.8% (24/43). The image of lipiodol flowing into the vein showed obstruction at the venous angle. There were 60.5%(26/43) of the patients with lipiodol reflux through the bronchomediastinal trunk (type Ⅰ), 11.6%(5/43) with lipiodol diffusion to the pericardium through the abnormal pathway from the thoracic segment of the thoracic duct (type Ⅱ), while no communication pathway between the thoracic duct and the pericardial cavity (type Ⅲ) found in 27.9%(12/43). CT images obtained after the direct lymphangiography showed 34.9%(15/43) had abnormal distribution of lipiodol in pericardium, mediastinal lymph nodes and lung hilar lymph nodes, 46.5%(20/43) in mediastinal lymph nodes and lung hilar lymph nodes, 14.0%(6/43) only mediastinal lymph nodes, 4.6%(2/43) had no lipiodol in the above areas. Conclusions: Pericardial effusion compared with same period blood, has higher triglyceride, lower total cholesterol, total protein and albumin. The obstruction of the cervical segment of the thoracic duct and the formation of abnormal reflux branches would be corelative to primary isolated chylopericardium.

Analysis of Stroke Detection during the COVID-19 Pandemic Using Natural Language Processing of Radiology Reports

BACKGROUND AND PURPOSE

The coronavirus disease 2019 (COVID-19) pandemic has led to decreases in neuroimaging volume. Our aim was to quantify the change in acute or subacute ischemic strokes detected on CT or MR imaging during the pandemic using natural language processing of radiology reports.

MATERIALS AND METHODS

We retrospectively analyzed 32,555 radiology reports from brain CTs and MRIs from a comprehensive stroke center, performed from March 1 to April 30 each year from 2017 to 2020, involving 20,414 unique patients. To detect acute or subacute ischemic stroke in free-text reports, we trained a random forest natural language processing classifier using 1987 randomly sampled radiology reports with manual annotation. Natural language processing classifier generalizability was evaluated using 1974 imaging reports from an external dataset.

RESULTS

The natural language processing classifier achieved a 5-fold cross-validation classification accuracy of 0.97 and an F1 score of 0.74, with a slight underestimation (-5%) of actual numbers of acute or subacute ischemic strokes in cross-validation. Importantly, cross-validation performance stratified by year was similar. Applying the classifier to the complete study cohort, we found an estimated 24% decrease in patients with acute or subacute ischemic strokes reported on CT or MR imaging from March to April 2020 compared with the average from those months in 2017-2019. Among patients with stroke-related order indications, the estimated proportion who underwent neuroimaging with acute or subacute ischemic stroke detection significantly increased from 16% during 2017-2019 to 21% in 2020 (P = .01). The natural language processing classifier performed worse on external data.

CONCLUSIONS

Acute or subacute ischemic stroke cases detected by neuroimaging decreased during the COVID-19 pandemic, though a higher proportion of studies ordered for stroke were positive for acute or subacute ischemic strokes. Natural language processing approaches can help automatically track acute or subacute ischemic stroke numbers for epidemiologic studies, though local classifier training is important due to radiologist reporting style differences.

The Healthy Start scheme and its association with food expenditure in low-income families in the UK

Background

The Healthy Start programme is a statutory benefit-in-kind in the United Kingdom (UK) which aims to enable low-income families to purchase fruit, vegetables, cow's milk and infant formula through the provision of vouchers. The scheme was introduced in 2006, however, the effect on food purchasing in participating households has not been evaluated within an eligible population. This study aimed to determine whether participation in the Healthy Start (HS) scheme is associated with differences in food purchasing in a representative sample of households in the United Kingdom.

Methods

Cross-sectional analysis of the Living Costs and Food Survey dataset (2010-2017). All households with a child (0-3 years) or pregnant woman were included in the analysis (n = 4,869). Multivariable quantile regression was used to compare the expenditure and quantity of fruit and vegetable, infant formula and total food purchases between Healthy Start participating, eligible non-participating, nearly-eligible and ineligible households.

Results

54% (n = 475) of eligible households participated in Healthy Start. After accounting for covariates, no significant difference was found in the quantity or expenditure of fruit and vegetable purchases between Healthy Start participating and non-participating households. Fruit and vegetable expenditure (£/week) was found to be higher in nearly eligible (β1.60; 95% CI 0.79, 2.41) and ineligible households (β2.56; 95% CI 1.77, 3.35) compared to Healthy Start eligible households.

Conclusions

The present study did not demonstrate significant differences in the fruit and vegetable expenditure of HS participating and non-participating households. The analysis demonstrates that inequalities in fruit and vegetable purchasing persists in the UK. Improved participation and increased voucher value may be needed to promote well-being and counteract the harmful effect of poverty on fruit and vegetables purchasing.

Key messages

The study found no evidence of different food purchases between Healthy Start participating and non-participating households. Increased voucher value may be needed to counteract food-price inflation. The paper reflected persistent socioeconomic inequalities in the UK, indicating the Healthy Start scheme does not sufficiently counteract the harmful effects of poverty on food purchasing.

Automatic Machine Learning to Differentiate Pediatric Posterior Fossa Tumors on Routine MR Imaging

BACKGROUND AND PURPOSE

Differentiating the types of pediatric posterior fossa tumors on routine imaging may help in preoperative evaluation and guide surgical resection planning. However, qualitative radiologic MR imaging review has limited performance. This study aimed to compare different machine learning approaches to classify pediatric posterior fossa tumors on routine MR imaging.

MATERIALS AND METHODS

This retrospective study included preoperative MR imaging of 288 patients with pediatric posterior fossa tumors, including medulloblastoma (n = 111), ependymoma (n = 70), and pilocytic astrocytoma (n = 107). Radiomics features were extracted from T2-weighted images, contrast-enhanced T1-weighted images, and ADC maps. Models generated by standard manual optimization by a machine learning expert were compared with automatic machine learning via the Tree-Based Pipeline Optimization Tool for performance evaluation.

RESULTS

For 3-way classification, the radiomics model by automatic machine learning with the Tree-Based Pipeline Optimization Tool achieved a test micro-averaged area under the curve of 0.91 with an accuracy of 0.83, while the most optimized model based on the feature-selection method χ2 score and the Generalized Linear Model classifier achieved a test micro-averaged area under the curve of 0.92 with an accuracy of 0.74. Tree-Based Pipeline Optimization Tool models achieved significantly higher accuracy than average qualitative expert MR imaging review (0.83 versus 0.54, P < .001). For binary classification, Tree-Based Pipeline Optimization Tool models achieved an area under the curve of 0.94 with an accuracy of 0.85 for medulloblastoma versus nonmedulloblastoma, an area under the curve of 0.84 with an accuracy of 0.80 for ependymoma versus nonependymoma, and an area under the curve of 0.94 with an accuracy of 0.88 for pilocytic astrocytoma versus non-pilocytic astrocytoma.

CONCLUSIONS

Automatic machine learning based on routine MR imaging classified pediatric posterior fossa tumors with high accuracy compared with manual expert pipeline optimization and qualitative expert MR imaging review.

Learning curve in robotic transabdominal preperitoneal (rTAPP) ventral hernia repair: a cumulative sum (CUSUM) analysis

Purpose

rTAPP-VHR is a novel technique which may be added to a surgeon’s armamentarium. We aim to evaluate the robotic transabdominal preperitoneal ventral hernia repair (rTAPP-VHR) learning curve based on operative times while accounting for peritoneal flap integrity.

Methods

We performed a retrospective analysis of a database collected over a 7-year period. Patients with primary ventral hernias were included and a cumulative sum analysis(CUSUM) was used to create learning curves for three subsets of operative times. A risk-adjusted CUSUM (RA-CUSUM) accounted for repair quality based on peritoneal flap completeness. The flap was considered as incomplete when peritoneal gaps were unable to be closed.

Results

105 patients undergoing rTAPP-VHR were included. Learning curves were created for skin-to-skin, console, and off-console times. Patients were divided into three phases. In terms of skin-to-skin times, both phase 2&3 had a mean 11 min shorter than that of phase 1 (p = 0.0498, p = 0.0245, respectively), with a steady decrease after forty-six cases. An incomplete peritoneal flap was noted in 25/36 patients in phase 1, as compared to 5/24 and 5/45 patients in phase 2&3, respectively. When risk-adjusted for peritoneal flap completeness, gradually decreasing skin-to-skin times were observed after sixty-one cases. In terms of off-console times, the mean across three phases was 14 min, with marked improvement after forty-three cases.

Conclusions

Forty-six cases were needed to achieve steadily decreasing operative times. We can assume that ensuring good-quality repairs, through maintenance of peritoneal flap integrity, was gradually improved after sixty-one cases. Moreover, familiarization with port placements and robotic docking was accomplished after forty-three cases.

Improving CO2 Electrochemical Reduction to CO Using Space Confinement between Gold or Silver Nanoparticles

Developing electrocatalysts that are stable and efficient for CO₂ reduction is important for constructing a carbon-neutral energy cycle. New approaches are required to drive input electricity toward the desired CO₂ reduction reaction (CO₂RR) rather than the competitive hydrogen evolution reaction (HER). In this study, we have used quantum mechanics to demonstrate that the space confinement formed in the gaps of adjacent gold or silver nanoparticles can be used to improve the Faradaic efficiency of CO₂RR to CO. This behavior is due to the space confinement stabilizing *COOH, which is the key intermediate in the CO₂RR. However, space confinement has almost no effect on *H, which is the key intermediate in the HER. Possible experimental approaches for the preparation of this type of gold or silver electrocatalyst have been proposed.

Large-scale analysis of acquired chromosomal alterations in non-tumor samples from patients with cancer

Mosaicism, the presence of subpopulations of cells bearing somatic mutations, is associated with disease and aging and has been detected in diverse tissues, including apparently normal cells adjacent to tumors. To analyze mosaicism on a large scale, we surveyed haplotype-specific somatic copy number alterations (sCNAs) in 1,708 normal-appearing adjacent-to-tumor (NAT) tissue samples from 27 cancer sites and in 7,149 blood samples from The Cancer Genome Atlas. We find substantial variation across tissues in the rate, burden and types of sCNAs, including those spanning entire chromosome arms. We document matching sCNAs in the NAT tissue and the adjacent tumor, suggesting a shared clonal origin, as well as instances in which both NAT tissue and tumor tissue harbor a gain of the same oncogene arising in parallel from distinct parental haplotypes. These results shed light on pan-tissue mutations characteristic of field cancerization, the presence of oncogenic processes adjacent to cancer cells.

The Nab experiment: A precision measurement of unpolarized neutron beta decay

Neutron beta decay is one of the most fundamental processes in nuclear physics and provides sensitive means to uncover the details of the weak interaction. Neutron beta decay can evaluate the ratio of axial-vector to vector coupling constants in the standard model, λ = gA/gV, through multiple decay correlations. The Nab experiment will carry out measurements of the electron-neutrino correlation parameter a with a precision of δa/a = 10−3 and the Fierz interference term b to δb = 3 × 10−3 in unpolarized free neutron beta decay. These results, along with a more precise measurement of the neutron lifetime, aim to deliver an independent determination of the ratio λ with a precision of δλ/λ = 0.03% that will allow an evaluation of Vud and sensitively test CKM unitarity, independent of nuclear models. Nab utilizes a novel, long asymmetric spectrometer that guides the decay electron and proton to two large area silicon detectors in order to precisely determine the electron energy and an estimation of the proton momentum from the proton time of flight. The Nab spectrometer is being commissioned at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source at Oak Ridge National Lab. We present an overview of the Nab experiment and recent updates on the spectrometer, analysis, and systematic effects.

Early Maladaptive Schemas, Depression Severity, and Risk Factors for Persistent Depressive Disorder: a Cross-sectional Study

OBJECTIVE

To investigate associations of the five early maladaptive schemas (EMS) domains with depression severity by comparing patients with persistent depressive disorder (PDD), patients with major depressive disorder (MDD), and controls with no psychiatric disorders.

METHODS

Patients with PDD (n = 30), patients with MDD (n = 24), and controls with no psychiatric disorders (n = 30) were recruited. Participants were assessed using the Mini-International Neuropsychiatric Interview 5.0 version (MINI), the Beck Depression Inventory-Second Edition (BDI-II), and the Young Schema Questionnaire-3rd Edition Short Form (YSQ-S3).

RESULTS

The five EMS domains (YSQ-S3 score) significantly correlated with depression severity (BDI-II score), with correlation coefficients ranging from 0.583 to 0.788. After controlling for age, education, and sex, the two best predictors of depression severity were domains 'over-vigilance and inhibition' and 'disconnection and rejection'. For domains of disconnection and rejection, impaired autonomy and performance, and over-vigilance and inhibition, the total YSQ-S3 score was significantly higher in the PDD group than both the MDD and control groups. For the domain of impaired limits, the total YSQ-S3 score was significantly higher in both the PDD and MDD groups than the control group.

CONCLUSION

All five EMS domains correlated significantly with depression severity. PDD and MDD differed in psychopathology. The EMS domains of disconnection and rejection, impaired autonomy and performance, and over-vigilance and inhibition may be specific risk factors for PDD.

Volumetric laser endomicroscopy and its application to Barrett's esophagus: results from a 1,000 patient registry

Volumetric laser endomicroscopy (VLE) uses optical coherence tomography (OCT) for real-time, microscopic cross-sectional imaging. A US-based multi-center registry was constructed to prospectively collect data on patients undergoing upper endoscopy during which a VLE scan was performed. The objective of this registry was to determine usage patterns of VLE in clinical practice and to estimate quantitative and qualitative performance metrics as they are applied to Barrett's esophagus (BE) management. All procedures utilized the NvisionVLE Imaging System (NinePoint Medical, Bedford, MA) which was used by investigators to identify the tissue types present, along with focal areas of concern. Following the VLE procedure, investigators were asked to answer six key questions regarding how VLE impacted each case. Statistical analyses including neoplasia diagnostic yield improvement using VLE was performed. One thousand patients were enrolled across 18 US trial sites from August 2014 through April 2016. In patients with previously diagnosed or suspected BE (894/1000), investigators used VLE and identified areas of concern not seen on white light endoscopy (WLE) in 59% of the procedures. VLE imaging also guided tissue acquisition and treatment in 71% and 54% of procedures, respectively. VLE as an adjunct modality improved the neoplasia diagnostic yield by 55% beyond the standard of care practice. In patients with no prior history of therapy, and without visual findings from other technologies, VLE-guided tissue acquisition increased neoplasia detection over random biopsies by 700%. Registry investigators reported that VLE improved the BE management process when used as an adjunct tissue acquisition and treatment guidance tool. The ability of VLE to image large segments of the esophagus with microscopic cross-sectional detail may provide additional benefits including higher yield biopsies and more efficient tissue acquisition. Clinicaltrials.gov NCT02215291.

Enhancing Activity and Reducing Cost for Electrochemical Reduction of CO2 by Supporting Palladium on Metal Carbides

Electrochemical CO₂ reduction reaction (CO₂ RR) with renewable electricity is a potentially sustainable method to reduce CO₂ emissions. Palladium supported on cost-effective transition-metal carbides (TMCs) are studied to reduce the Pd usage and tune the activity and selectivity of the CO₂ RR to produce synthesis gas, using a combined approach of studying thin films and practical powder catalysts, in situ characterization, and density functional theory (DFT) calculations. Notably, Pd/TaC exhibits higher CO₂ RR activity, stability and CO Faradaic efficiency than those of commercial Pd/C while significantly reducing the Pd loading. In situ measurements confirm the transformation of Pd into hydride (PdH) under the CO₂ RR environment. DFT calculations reveal that the TMC substrates modify the binding energies of key intermediates on supported PdH. This work suggests the prospect of using TMCs as low-cost and stable substrates to support and modify Pd for enhanced CO₂ RR activity.

Colorectal premalignancy is associated with consensus molecular subtypes 1 and 2

Background

Gene expression-based profiling of colorectal cancer (CRC) can be used to identify four molecularly homogeneous consensus molecular subtype (CMS) groups with unique biologic features. However, its applicability to colorectal premalignant lesions remains unknown.

Patients and methods

We assembled the largest transcriptomic premalignancy dataset by integrating different public and proprietary cohorts of adenomatous and serrated polyps from sporadic (N = 311) and hereditary (N = 78) patient populations and carried out a comprehensive analysis of carcinogenesis pathways using the CMS random forest (RF) classifier.

Results

Overall, transcriptomic subtyping of sporadic and hereditary polyps revealed CMS2 and CMS1 subgroups as the predominant molecular subtypes in premalignancy. Pathway enrichment analysis showed that adenomatous polyps from sporadic or hereditary cases (including Lynch syndrome) displayed a CMS2-like phenotype with WNT and MYC activation, whereas hyperplastic and serrated polyps with CMS1-like phenotype harbored prominent immune activation. Rare adenomas with CMS4-like phenotype showed significant enrichment for stromal signatures along with transforming growth factor-β activation. There was a strong association of CMS1-like polyps with serrated pathology, right-sided anatomic location and BRAF mutations.

Conclusions

Based on our observations made in premalignancy, we propose a model of pathway activation associated with CMS classification in colorectal carcinogenesis. Specifically, while adenomatous polyps are largely CMS2, most hyperplastic and serrated polyps are CMS1 and may transition into other CMS groups during evolution into carcinomas. Our findings shed light on the transcriptional landscape of premalignant colonic polyps and may help guide the development of future biomarkers or preventive treatments for CRC.