bluuebunny/crossref_metadata_2025 huggingface dataset:
Immobilization of CMP‐Sialic Acid Synthetase and α2,3‐Sialyltransferase for Cascade Synthesis of 3′‐Sialyl β‐D‐Galactoside with Enzyme Reuse
Authors: Schelch Sabine , Koszagova Romana , Kuballa Jürgen , Nidetzky Bernd
Published: March 2022

Sialo‐oligosaccharides are often synthesized via cascade reaction of CMP‐sialic acid synthetase (CSS) and sialyltransferase (SiaT). Here, we studied individual enzyme immobilization to develop solid‐supported preparations of the CSS from Neisseria meningitis (NmCSS) and the α2,3‐SiaT from Pasteurella dagmatis (PdSiaT). Oriented immobilization via N‐terminal His‐tag as well as “random” (orientationally uncontrolled) immobilization via multipoint covalent coupling gave catalyst preparations of each enzyme with low activity and effectiveness factor (η). We therefore constructed N‐terminal fusions of NmCSS and PdSiaT with the cationic binding module Zbasic2 and show individual immobilization of even the unpurified enzymes on sulfonate carrier (ReliSorb SP400) in excellent yields (≥95 %) and binding selectivities. For both enzymes in individual reactions, the initial η (Z‐NmCSS: 90 %; Z‐PdSiaT: 25 %) declined sharply with increasing enzyme loading and the maximum immobilized activity was 110 U/g carrier (η=27 %) for Z‐NmCSS, 7.5 U/g (η≤5 %) for Z‐PdSiaT. Supplied with neuraminic acid and cytidine 5′‐triphosphate (20 mM each), the immobilized enzymes promoted α2,3‐sialylation of the model substrate 4‐nitrophenyl β‐D‐galactoside (20 mM) in 85 % yield and could be recycled 5 times with only small loss in their overall synthetic activity (≤10 %).
Mo‐Vacancies Defect Engineering of One‐Dimensional Porous Mo2C Nanowires for Enhanced High‐Efficiency Hydrogen Evolution
Authors: Nie Zhongxiang , Tang Zeming , Jiao Dongxu , Yuan MeiChen , Zhao Jingxiang , Lai Qingxue , Liang Yanyu
Published: March 2022

The large‐scale application of efficient water‐splitting greatly promote the development of hydrogen economy which benefit both in alleviating the energy crisis and reaching the goal of carbon neutral. To realize considerable hydrogen evolution, rational design of catalysts with controllable structure and surface composition become crucial. In this work, we proposed an enhanced active site originated from Mo‐vacancies defect in Mo2C crystal which was fabricated by the evaporation of Zn content in well‐designed one‐dimensional ZnMoO4 precursor. Density functional theory calculation and experimental results demonstrated that the formation of molybdenum vacancies in molybdenum carbide promoted the water adsorption and H2 desorption effectively, resulting in an excellent HER reaction dynamics. Moreover, one‐dimensional porous nanowires also ensured rapid mass transfer and contributed strong support for superexcellence HER performance. As expected, V−Mo2C‐900@NF exhibited extremely low overpotential (η10=43 mV) at the current density of 10 mA cm−2 and rapid reaction kinetics (Tafel slope 77.89 mV dec−1).
Underwater Superoleophobic‐Oleophilic Chips for Femtomolar Aflatoxins Identification
Authors: Cao Liwei , Wu Lizhen , Li Cheng , Tu Yidan , Wu Hao , Shen Bin , Meng Jianxin , Hao Xin‐Qi , Yan Bing , Li Feng‐yu , Xia Fan , Huang Yu
Published: March 2022

Comprehensive Summary

Underwater superoleophobic‐oleophilic chips were developed to achieve oil extracting from aqueous solution and oil‐droplet condensing to preset microwell. The double‐hierarchical (extracting‐condensing) enrichment strategy drastically improves the sensitivity for organic contaminants or components, whose signal amplification approaches 459.7 times that of primary solution and 25.9 times that of single condensing enrichment strategy. Low to femtomolar limit of detection (2.6 × 10–15 mol/L) sensitivity and 6 various aflatoxins or mildewed foods identification demonstrate the significance and promotion for environment monitoring, water purification, and so on.
Advances and Challenges of Photocatalytic Methane C—C Coupling
Authors: Wang Xueyuan , Luo Nengchao , Wang Feng
Published: March 2022

Comprehensive Summary

Methane, the main component of natural gas and shale gas, can be converted to upgraded fuels, syngas and value‐added chemicals. Due to the nonpolar character of methane and large bond dissociation energy of sp3 C—H bond, methane conversion requires strong oxidants or acids/bases for its activation. Photocatalysis capable of inducing highly oxidative surrogates enables methane C—H bond scission at room temperature, thereby avoiding side reactions and coke formation caused by high reaction temperature. The scission of methane C—H bond generates •CH3 that may undergo C—C bond coupling with carbon radicals, which is a versatile way to obtain C2+ chemicals. Apart from the kinetically slow activation of methane C—H bond, photocatalysis also suffers from complex product distributions owing to the presence of varieties of radicals during photocatalytic methane conversion, and a low selectivity of desired C2+ products was achieved. In this review, we summarize the recent advances of photocatalytic methane conversion with emphasis on methane C—C bond coupling. Methods of methane C—H bond activation and radical manipulation for selective C—C bond coupling were discussed in detail. We hope this review may be a valuable guide of future work in photocatalytic methane C—C coupling.
Disparities in smoking prevalence and associations with mental health and substance use disorders in underserved communities across the United States
Authors: Lin Sue C. , Gathua Naomie , Thompson Cheryl , Sripipatana Alek , Makaroff Laura
Published: March 2022

Background

Smoking contributes to the top 3 deadliest cancers, cancers of the lung, colon, and pancreas, which account for nearly 40% of all cancer‐related deaths in the United States. Despite historicly low smoking rates, substantial disparities remain among people with mental health conditions and substance use disorders (SUDs).

Methods

The study examined the prevalence of smoking among adults from underserved communities who are served at federally qualified health centers through an analysis of the 2014 Health Center Patient Survey. Furthermore, the study assessed associations of smoking with co‐occurring mental health conditions and SUDs among adult smokers (n = 1735).

Results

The prevalence of smoking among health center patients was 28.1%. Among current smokers, 59.1% had depression and 45.4% had generalized anxiety. Non‐Hispanic Black smokers had more than 2 times the odds of reporting SUDs (adjusted odds ratio [aOR], 2.13; 95% confidence interval [CI], 1.06‐4.30). Individuals at or below 100% of the federal poverty level had more than 2 times the odds of having mental health conditions (aOR, 2.55; 95% CI, 1.58‐4.11), and those who were unemployed had more than 3 times the odds for SUDs (aOR, 3.21; 95% CI, 1.27‐8.10).

Conclusions

The prevalence of smoking in underserved communities is nearly double the national prevalence. In addition, the study underscores important socioeconomic determinants of health in smoking cessation behavior and the marked disparities among individuals with mental health conditions and SUDs. Finally, the findings illuminate the unique need for tailored treatments supporting cancer prevention care to address challenges confronted by vulnerable populations.
Formation of the Metastable MnIII Water Oxidation Intermediate in Birnessite is Controlled by a Dissolution‐Deposition Process Involving Labile MnII
Authors: Roy Indroneil , Wang Chenying , Smieszek Nicholas , Li Xinran , Tsapatsaris Leonidas , Chakrapani Vidhya
Published: March 2022

Birnessite, the closest naturally occurring analog of the Mn4CaO5 cluster of photosystem II, is an important model compound in the development of bio‐inspired electrocatalysts for the water oxidation reaction. The present work reports the formation mechanism of the key MnIII intermediate realized through the study of the effects of several electrolyte anions and cations on the catalytic efficiency of birnessite. In situ spectroelectrochemical measurements show that the activity is controlled by a dynamic dissolution‐oxidation process, wherein MnIII is formed through the oxidation of labile uncomplexed MnII that reversibly shuttles between the birnessite and the electrolyte in a manner similar to the photoactivation in photosystem II. The role of electrolyte cations of different ionic radii and hydration strengths is to control the interlayer spacing, whereas electrolyte anions control the extent of deprotonation of complexed MnII in the lattice. Both in turn govern the shuttling efficiency of uncomplexed MnII and its subsequent electro‐oxidation to MnIII.
Model predictive direct power control strategy for leakage current suppression on a grid‐connected three‐level inverter
Authors: Gao Fengyang , Yang Kaiwen , Luo Yinhang , Gao Jianning , Song Zhixiang , Gao Xuanyu
Published: March 2022

The nonisolated grid‐connected photovoltaic inverter system suffers from the problem of leakage current. Therefore, a leakage current suppression control strategy based on the model predictive direct power control is proposed for the three‐level four‐leg grid‐connected inverter. At first, the system model is established to analyze the factors that affect the leakage current and the potential of the neutral point. Second, the first three legs, inverting part, use model predictive direct power control, and the fourth leg of the inverter is used to maintain a constant common‐mode voltage to achieve the suppression of the leakage current. The fourth leg is indirectly controlled by the switch state of the first three legs; thus, the number of optimization times is reduced. Finally, by simulation, the leakage current is compared and analyzed with the three‐level three‐leg inverter under conditions with different parasitic capacitance values. The results show that the proposed strategy suppresses the leakage current by more than 60% without affecting the neutral point potential and has a fast optimization speed.
Graduate and professional students face obstacles, financial hardships during COVID‐19 pandemic
Authors: Hope Joan
Published: March 2022

Graduate and professional students with disabilities have faced significantly more obstacles to graduation and more financial hardships during the COVID‐19 pandemic than their nondisabled peers, according to two research briefs prepared by the National Center for College Students with Disabilities.
Intelligent structural design of shear wall residence using physics‐enhanced generative adversarial networks
Authors: Lu Xinzheng , Liao Wenjie , Zhang Yu , Huang Yuli
Published: March 2022

Intelligent structural design using generative adversarial networks (GANs) is a revolutionary design approach for building structures. Despite its far‐reaching capability, the data quantity and quality may have limited the performance of such a data‐driven network. This study proposes to enhance the objectiveness of training processes by innovatively introducing a surrogate model, Physics Estimator, that informs the generator by appraising the physical behavior of the generated design. Dual loss functions evaluated by a traditional data‐driven discriminator and the Physics Estimator collaboratively foster the physics‐enhanced GAN architecture. We further develop a structural mechanics model to train and optimize the inherent accuracy of the Physics Estimator. The comparative study suggests that the proposed physics‐enhanced GAN can generate structural designs from architectural drawings and specified design conditions 44% better than a data‐driven design method and 90 times faster than a competent engineer.
Solution of transient heat transfer in graded‐material fins of varying thickness under step changes in boundary conditions using the Lattice Boltzmann Method
Authors: Sahu Abhishek , Bhowmick Shubhankar
Published: March 2022

Graded materials (GM) possess superior thermo‐mechanical properties, which are not feasible to obtain with homogeneous materials (HM), and hence in this paper, the transient response of a longitudinal fin of varying geometry made up of GM is reported. The temperature‐dependent convection coefficient and heat generation parameters are considered to account for real‐world high‐temperature applications of fins. Fin material properties such as density and specific heat remain constant while thermal conductivity is assumed to vary axially based on four different physically possible variations namely, linear, quadratic, power, and exponential variations. The typical nonlinear differential equation obtained for fins was solved by using a mesoscopic scale‐based particle tracking method called the Lattice Boltzmann method. The Lattice Boltzmann solver has been implemented in form of an in‐house MATLAB code and validated with existing results, thereafter it is developed for solving the foregoing problems. The results obtained are reported for rectangular, triangular, convex, and concave profiles under step change in base temperature and base heat flux. The performance of graded fins is investigated in terms of time required to attain steady‐state and fin tip temperature which are inherent design parameters in the case of the transient fin. Inhomogeneity index and profile function have a significant effect on the performance of fin in terms of resistance to heat flow. Hereby, in comparison with HM fins, GM fins have lower resistance to heat flow irrespective of fin profiles. Concurrently, comparative analysis for fins of different profiles made of HM and GM is also done to facilitate the designer in selecting the most appropriate fins.
Targeting population groups with heavier burden of hepatocellular carcinoma incidence: A nationwide descriptive epidemiological study in Sweden
Authors: Vaz Juan , Midlöv Patrik , Eilard Malin Sternby , Eriksson Berne , Buchebner David , Strömberg Ulf
Published: March 2022

Contemporary European studies examining associations between socioeconomic status and hepatocellular carcinoma (HCC) incidence are scarce. We aimed to target population groups with a heavier burden of HCC by assessing associations of individual‐level sociodemographic variables and neighbourhood deprivation with all‐stage and stage‐specific HCC incidence rates (IR). Patient and population data stratified by calendar year (2012‐2018), sex, age (5‐year groups), household income (low, medium and high), country of birth (Nordic, non‐Nordic) and neighbourhood deprivation (national quintiles Q1‐Q5) were retrieved from Swedish registers. HCC stages were defined by Barcelona Clinic Liver Cancer stages 0 to A (early‐stage) and B to D (late‐stage). IR (per 100 000 person‐years) were estimated by Poisson regression models. Men had four times higher IR than women. IRs increased markedly with lower household income as well as with neighbourhood deprivation. Seven times higher IR was observed among people with a low household income living in the most deprived neighbourhoods (IR 3.90, 95% confidence interval [CI] 3.28‐4.64) compared to people with a high household income living in the least deprived neighbourhoods (IR 0.58, 95% CI 0.46‐0.74). The gradient across income categories was more pronounced for late‐stage than early‐stage HCC. IR reached 30 (per 100 000 person‐years) for people in the age span 60 to 79 years with low income and 20 for 60 to 79 year old people living in the most deprived neighbourhoods (regardless of income). Men with low household income and/or living in the most deprived neighbourhoods might be considered as primary targets in studies evaluating the cost‐effectiveness of screening for early‐stage HCC detection.
Next generation internet oriented online English teaching system
Authors: Wang Chuncheng
Published: March 2022

With the continuous development of information technology all around this world, great changes have taken place in the teaching methods of English courses in colleges and universities. The implementation of online English teaching through networking and information technology has become an inevitable development trend in the future. Therefore, this paper proposes a multimedia English teaching system based on Internet virtual technology, which aims to further expand the implementation path of English teaching in colleges and universities and improve the information level of English teaching. First of all, this paper analyzes the working principle of the English teaching classroom distance teaching system, and constructs the three‐tier architecture of the English teaching classroom distance teaching system. Then, the system is designed based on Internet technology, and the output control of long‐distance multimedia teaching information is realized by using the core control module of Internet. Finally, the virtual teaching environment is created by using virtualization technology to realize the interaction between scene objects and users, and show the teaching effect smoothly. The final experimental results show that the designed system can interact in real time. It improves the fun of students' English practice and teaching effect, and the performance of the system is stable.
Maternal closeness, kinship ties, and future orientation among rural African American youth: The mediating role of ethnic identity
Authors: Harris Charlene , Alexander Jamie D. , Vazsonyi Alexander T.
Published: March 2022

Introduction

Few studies have considered the importance of kin or extended family relationships on future orientation. Additionally, some of the underlying processes linking social bonds to future orientation remain poorly understood. Based on theoretical work focused on attachment and identity, this study tested the potential mediating effects of ethnic identity on the links between close relationships (maternal closeness and kinship ties) and future orientation over time. Specifically, the study tested the extent to which ethnic identity mediated the relationship between maternal closeness and future orientation, and the relationship between kinship ties and future orientation. In addition, it tested whether sex moderated the relationships between maternal closeness/kinship ties and future orientation measures (education and career) as well as between ethnic identity and future orientation measures.

Methods

Self‐report data were collected twice, approximately 6 months apart, during a school year from a sample of rural African American adolescents (n = 274, Mage = 14.81, SD = 1.48).

Results

Findings provided evidence of mediation effects by ethnic identity on the relationships between maternal closeness and future orientation measures, and the link between kinship ties and future orientation measures. In addition, sex moderated the associations between ethnic identity and future education orientation as well as between maternal closeness and future education orientation; no moderation effects were found for the links with future career orientation measures.

Conclusions

Maternal closeness and kinship ties appear to be critical for supporting ethnic identity and for developing educational and career future orientation among rural African American youth.
Cross‐national and longitudinal evidence for a rapid decline in life satisfaction in adolescence
Authors: Daly Michael
Published: March 2022

Introduction

While several studies have documented a declining‐with‐age trend in life satisfaction in adolescence, cross‐national and nationally representative longitudinal evidence is needed to establish the normative trajectory of life satisfaction during this critical developmental period.

Methods

The Health Behaviour in School‐Aged Children (HBSC) study of 10–16‐year‐olds included the Cantril Ladder life satisfaction measure in surveys of 43 countries between 2001 and 2014 (N = 752,620, 51% females). The UK Household Longitudinal Study (UKHLS) was used to assess within‐person changes in life satisfaction from age 10 to 15 years among young people sampled between 2009 and 2018 (N = 8952, Obs. = 30,278).

Results

Life satisfaction decreased by 0.61 SDs on average from ages 10 to 16 in the HBSC sample. A statistically significant decreasing‐with‐age trend was observed in each of the 43 countries examined. Females experienced a more pronounced decline in life satisfaction than males (0.75 SD vs. 0.46) on average, and a significantly larger decrease in life satisfaction among females was identified in 38 of 43 countries examined. Longitudinal analysis of adolescents from the UKHLS sample replicated this pattern: life satisfaction declined significantly by 0.5 SD between the ages of 10 and 15 and this decline was found to be steeper for females (0.76 SD) than for males (0.23SD).

Conclusions

The study findings enhance our understanding of the lifespan dynamics of life satisfaction and point to a potential universal decline in life satisfaction in adolescence. Understanding the developmental processes underlying this phenomenon will now be crucial.
Front Cover
Authors: Penjweini Rozhin , Roarke Branden , Alspaugh Greg , Link Katie A. , Andreoni Alessio , Mori Mateus P. , Hwang Paul M. , Sackett Dan L. , Knutson Jay R.
Published: March 2022

Penjweini et al. describe a new ‘sandwich’ probe comprised of two different fluorescent proteins that (via FRET and FLIM methods) read out the state of a myoglobin linked between them. The mCherry emission lifetime is primarily sensitive to oxygen binding, while the EYFP lifetime instead serves to read out the met state of myoglobin. That latter state is a valuable indicator of ROS or NO exposure.

Further details can be found in the article by R. Penjweini, B. Roarke, G. Alspaugh, K. A. Link, A. Andreoni, M. P. Mori, P. M. Hwang, D. L. Sackett, J. R. Knutson (e202100166).

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Pegylated insulin‐like growth factor‐1 biotherapeutic delivery promotes rotator cuff regeneration in a rat model
Authors: Prabhath Anupama , Vernekar Varadraj N. , Esdaille Caldon J. , Eisenberg Ellen , Lebaschi Amir , Badon Mary , Seyedsalehi Amir , Dzidotor Godwin , Tang Xiaoyan , Dyment Nathaniel , Thomopoulos Stavros , Kumbar Sangamesh G. , Deymier Alix , Weber Eckhard , Laurencin Cato T.
Published: March 2022

Tears in the rotator cuff are challenging to repair because of the complex, hypocellular, hypovascular, and movement‐active nature of the tendon and its enthesis. Insulin‐like Growth Factor‐1 (IGF‐1) is a promising therapeutic for this repair. However, its unstable nature, short half‐life, and ability to disrupt homeostasis has limited its clinical translation. Pegylation has been shown to improve the stability and sustain IGF‐1 levels in the systemic circulation without disrupting homeostasis. To provide localized delivery of IGF‐1 in the repaired tendons, we encapsulated pegylated IGF‐1 mimic and its controls (unpegylated IGF‐1 mimic and recombinant human IGF‐1) in polycaprolactone‐based matrices and evaluated them in a pre‐clinical rodent model of rotator cuff repair. Pegylated‐IGF‐1 mimic delivery reestablished the characteristic tendon‐to‐bone enthesis structure and improved tendon tensile properties within 8 weeks of repair compared to controls, signifying the importance of pegylation in this complex tissue regeneration. These results demonstrate a simple and scalable biologic delivery technology alternative to tissue‐derived grafts for soft tissue repair.
Effects of brassinosteroids on cancer cells: A review
Authors: Ma Feifan , An Zaiyong , Yue Qiulin , Zhao Chen , Zhang Song , Sun Xin , Li Kunlun , Zhao Lin , Su Le
Published: March 2022

Brassinolide is a new type of steroidal hormone with strong activities, which is well known as an efficient and low‐toxicity plant growth regulator for a long time. Because steroidal hormones have a wide application prospect, brassinosteroids have been gradually explored in pharmacology and animal cells in recent decades. Brassinolide could effectively reverse the resistance of human T lymphoblastoid cell line CCRF‐VCR 1000 by inhibiting the effusion of drug transported by P‐glycoprotein. Brassinosteroids could also accelerate wound healing by positively eliminating inflammation and stimulating reepithelialization of the reparation stage. The occurrence of cancer is a multistep process mediated by a variety of factors. Until now, cancer has always been one group of the major diseases that threaten human health. Many studies have found that brassinosteroids have attracted a great deal of potential as an anticancer agent in the treatment of cancer cells, and most of them exert anticancer activity by inducing apoptosis in cancer cells. There are few articles on the relationship between brassinosteroids and cancer so far. Accordingly, in this article, we summarized current research about the brassinosteroids and cancers. Through the review, researchers could know more about brassinosteroids which might become a new tool for the treatment of cancer in the future, and not only a plant hormone.
A multilevel approach to social support as a determinant of mental health during COVID‐19
Authors: Schulder Talia , Rudenstine Sasha , Bhatt Krish J. , McNeal Kat , Ettman Catherine K. , Galea Sandro
Published: March 2022

The COVID‐19 pandemic has detrimentally affected the mental health of lower income communities. We sought to investigate the relationship among multilevel social support, specifically individual‐, network‐, and neighborhood‐level social supports, COVID‐19‐related stressors, and probable diagnoses of depression, anxiety, and posttraumatic stress (PTS), within a racially diverse and predominantly low‐socioeconomic status population. We used multiple logistic regressions to assess the odds of diagnosis for high versus low social support and stressor levels. Participants who endorsed high levels of stress had significantly higher odds of probable diagnoses. Participants who endorsed low individual‐level social support had higher odds of probable depression and anxiety. Those who endorsed low neighborhood‐level social support had higher odds of probable depression and probable PTS. Network‐level social support was not significantly associated with the health indicators of interest. Results indicate the importance of both individual‐ and neighborhood‐level support to protect mental health during COVID‐19.
Iron overload and impaired iron handling contribute to the dystrophic pathology in models of Duchenne muscular dystrophy
Authors: Alves Francesca M. , Kysenius Kai , Caldow Marissa K. , Hardee Justin P. , Chung Jin D. , Trieu Jennifer , Hare Dominic J. , Crouch Peter J. , Ayton Scott , Bush Ashley I. , Lynch Gordon S. , Koopman René
Published: March 2022

Background

Oxidative stress is implicated in the pathophysiology of Duchenne muscular dystrophy (DMD, caused by mutations in the dystrophin gene), which is the most common and severe of the muscular dystrophies. To our knowledge, the distribution of iron, an important modulator of oxidative stress, has not been assessed in DMD. We tested the hypotheses that iron accumulation occurs in mouse models of DMD and that modulation of iron through the diet or chelation could modify disease severity.

Methods

We assessed iron distribution and total elemental iron using LA‐ICP‐MS on skeletal muscle cross‐sections of 8‐week‐old Bl10 control mice and dystrophic mdx mice (with moderate dystrophy) and dystrophin/utrophin‐null mice (dko, with severe dystrophy). In addition, mdx mice (4 weeks) were treated with either an iron chelator (deferiprone 150 mg/kg/day) or iron‐enriched feed (containing 1% added iron as carbonyl iron). Immunoblotting was used to determine the abundance of iron‐ and mitochondria‐related proteins. (Immuno)histochemical and mRNA assessments of fibrosis and inflammation were also performed.

Results

We observed a significant increase in total elemental iron in hindlimb muscles of dko mice (+50%, P < 0.05) and in the diaphragm of mdx mice (+80%, P < 0.05), with both tissues exhibiting severe pathology. Iron dyshomeostasis was further evidenced by an increase in the storage protein ferritin (dko: +39%, P < 0.05) and ferroportin compared with Bl10 control mice (mdx: +152% and dko: +175%, P < 0.05). Despite having features of iron overload, dystrophic muscles had lower protein expression of ALAS‐1, the rate‐limiting enzyme for haem synthesis (dko −44%, P < 0.05), and the haem‐containing protein myoglobin (dko −54%, P < 0.05). Deferiprone treatment tended to decrease muscle iron levels in mdx mice (−30%, P < 0.1), which was associated with lower oxidative stress and fibrosis, but suppressed haem‐containing proteins and mitochondrial content. Increasing iron via dietary intervention elevated total muscle iron (+25%, P < 0.05) but did not aggravate the pathology.

Conclusions

Muscles from dystrophic mice have increased iron levels and dysregulated iron‐related proteins that are associated with dystrophic pathology. Muscle iron levels were manipulated by iron chelation and iron enriched feed. Iron chelation reduced fibrosis and reactive oxygen species (ROS) but also suppressed haem‐containing proteins and mitochondrial activity. Conversely, iron supplementation increased ferritin and haem‐containing proteins but did not alter ROS, fibrosis, or mitochondrial activity. Further studies are required to investigate the contribution of impaired ferritin breakdown in the dysregulation of iron homeostasis in DMD.
Growth and globalization of point‐of‐care ultrasound publications in emergency medicine
Authors: Belisle Haley Campbell , McKelvy Dina , Mackenzie David C.
Published: March 2022

Objectives

Since the introduction of point‐of‐care ultrasound (POCUS) in emergency medicine (EM), the applications, indications, and training for POCUS have grown. POCUS training in EM residency is standard and POCUS fellowships are common. We sought to quantify and characterize changes in POCUS publications over time with a scoping review of the literature

Methods

We conducted a structured keyword search of high impact EM journals according to 2019 journal citation reports and other journals publishing POCUS studies between 2000–2019. Two abstractors recorded whether the publication was POCUS related, the type of publication, and author affiliation by department and country. We included studies with at least one author affiliated with a department of EM. Agreement between abstractors was tested.

Results

The number of POCUS‐related publications grew from a mean of 8.8 publications/year 2000–2004 to 134.8 publications/year from 2015–2019. The most common publication type was case reports or series (44%). The proportion of publications from outside the United States (US) decreased over time. Between 2000 and 2004 89% of publications came from authors affiliated with US institutions; from 2015–2019 this had decreased to 64%. Agreement between abstractors was excellent (Cohen's k = 0.89)

Conclusions

POCUS publications increased substantially between 2000–2019. The most common type of publication was a case report, which was consistent throughout the study period. Authorship from outside the US increased. Publications yielding high‐quality evidence from observational or controlled studies represented a low proportion of the total number of studies.
Doppler hemodynamic liver index and hepatic elastic modulus: Advanced ultrasonographic techniques for non‐invasive prediction of esophageal varices in cirrhosis
Authors: Rana Abhilasha , Malik Amita , Krishnan Venkatram , Thakur Manisha
Published: March 2022

Purpose

Currently esophagoscopy is the gold standard for assessment of esophageal varices in cirrhosis. Predicting the presence of esophageal varices, varices needing treatment (VNT) and variceal grade by advanced ultrasonographic techniques using a combination of Doppler hemodynamic liver index (HDLI) (quantifying portal hypertension) and hepatic elastic modulus (quantifying hepatic fibrosis) would be a cost‐effective and non‐invasive alternative to routine endoscopy.

Methods

Our cross‐sectional study consisted of cirrhotic patients diagnosed using clinical features and laboratory parameters. Portal venous Doppler and liver sonoelastography were performed in selected subjects for obtaining measurements of HDLI (portal vein diameter/mean velocity) and hepatic elastic modulus respectively. Within 3 days of ultrasound, the subjects underwent upper GI endoscopy for assessment of presence, VNT and grade (F1, F2, F3) of varices. Subjects were divided into two groups (without and with varices) and data analyzed using XLSTAT.

Results

A total of 60 subjects (26 without and 34 with varices) were evaluated. Mean Doppler HDLI of subjects with varices was significantly higher (0.72 vs. 0.59, p < 0.0001) with progressive increase in values with variceal grade, being highest in grade‐F3 (mean 0.77). Likewise, mean hepatic elastic modulus was also higher in subjects with varices (28.9 vs. 12.6 kPa, p < 0.0001) and showed progressive increase with grade (51.1 kPa for F3). For predicting presence of varices, maximum accuracy of elastic modulus was at cut‐off of 14.5 kPa (sensitivity, specificity 83% and 84.6%) and Doppler HDLI was at 0.66 (66% and 92.3%). Good inter‐rater agreement was present (κ 0.66).

Conclusion

Combination of Doppler HDLI and hepatic elastic modulus is an excellent non‐invasive method for predicting the presence, VNT, and variceal grade and may obviate need for routine endoscopic screening in cirrhosis.
A systematic review of telehealth applications in hospital medicine
Authors: Gutierrez Jeydith , Rewerts Kelby , CarlLee Sheena , Kuperman Ethan , Anderson Melver L. , Kaboli Peter J.
Published: March 2022

Background

Despite the proliferation of telehealth, uptake for acute inpatient services has been slower. Hospitalist shortages in rural and critical access hospitals as well as the COVID‐19 pandemic have led to a renewed interest in telehealth to deliver acute inpatient services. Understanding current evidence is crucial for promoting uptake and developing evidence‐based practices.

Objective

To conduct a systematic review of telehealth applications in acute inpatient general medicine and pediatric hospital wards and synthesize available evidence.

Data Sources

A search of five databases (PubMed, CINAHL, Embase, Scopus, and ProQuest Theses, and Dissertations) using a combination of search terms including telemedicine and hospital medicine/inpatient care keywords yielded 17,015 citations.

Study Selection and Data Extraction

Two independent coders determined eligibility based on inclusion and exclusion criteria. Data were extracted and organized into main categories based on findings: (1) feasibility and planning, (2) implementation and technology, and (3) telehealth application process and outcome measures.

Results

Of the 20 publications included, three were feasibility and planning studies describing the creation of the program, services provided, and potential cost implications. Five studies described implementation and technology used, including training, education, and evaluation methods. Finally, twelve discussed process and outcome measures, including patient and provider satisfaction and costs.

Conclusion

Telehealth services for hospital medicine were found to be effective, well received, and initial cost estimates appear favorable. A variety of services were described across programs with considerable benefit appreciated by rural and smaller hospitals. Additional work is needed to evaluate clinical outcomes and overall program costs.
Increasing awareness of HIV pre‐exposure prophylaxis (PrEP) and willingness to use HIV PrEP among men who have sex with men: a systematic review and meta‐analysis of global data
Authors: Sun Zhishan , Gu Qianfei , Dai Yifan , Zou Huachun , Agins Bruce , Chen Qiaosen , Li Peiyang , Shen Junchun , Yang Yi , Jiang Hongbo
Published: March 2022

Introduction

Integrated knowledge regarding pre‐exposure prophylaxis (PrEP) awareness and willingness to use PrEP can be useful for HIV prevention in high incidence groups. This review summarizes the awareness of PrEP and willingness to use PrEP among men who have sex with men (MSM).

Methods

Online electronic databases were searched before 31 August 2021. A meta‐analysis was conducted to pool studies analysing PrEP awareness and willingness to use PrEP. LOESS regression and linear regression were applied to fit the trends over time for the proportion of MSM aware of PrEP and willing to use PrEP. Dose–response meta‐analysis (DRMA) was conducted by a restricted cubic spline model to explore the relationship between willingness to use PrEP and selected factors.

Results and Discussion

A total of 156 articles involving 228,403 MSM were included. The pooled proportions of MSM aware of PrEP and willing to use PrEP were 50.0 (95% CI: 44.8–55.2) and 58.6% (95% CI: 54.8–62.4), respectively. PrEP awareness varied among countries with different economic status and different WHO regions, among different publication and research years, PrEP types and support policies. PrEP willingness differed among countries with different economic status and groups with different risks of HIV. The awareness of PrEP increased from 2007 to 2019 with a slope of 0.040260 (p<0.0001), while the proportion of MSM willing to use PrEP decreased from 2007 to 2014 (slope = –0.03647, p = 0.00390) but increased after 2014 (slope = 0.04187, p = 0.03895). The main facilitators of willingness to use PrEP were PrEP awareness, condomless sexual behaviours, high perceived risk of HIV infection and influence of social network. The main barriers were doubts about the efficacy and side effects of PrEP. DRMA results indicated that MSM with more sexual partners and lower level of education were more willing to use PrEP. No publication bias was observed.

Conclusions

The proportions of PrEP awareness and willingness to use PrEP among MSM have increased since 2014, although the awareness was low and the willingness was moderate. Improving awareness of PrEP through increasing access to PrEP‐related health education and enhancing risk perceptions of HIV infection could have positive effects on the willingness to use PrEP among MSM.
South African healthcare workers’ knowledge of dolutegravir's drug–drug interactions in the first year of its rollout: a cross‐sectional online survey
Authors: Chisholm Briony S. , Swart Annoesjka M. , Blockman Marc
Published: March 2022

Introduction

In December 2019, dolutegravir‐based treatment was recommended as first‐line antiretroviral therapy (ART) in South Africa. Dolutegravir has clinically significant interactions with several commonly used drugs, such as rifampicin, metformin and cation‐containing medicines. National guidelines detail these interactions and how to manage them. While previous international studies have shown low healthcare worker knowledge of drug–drug interactions, there is a paucity of information on antiretroviral interaction knowledge in the South African setting, where much ART is nurse‐led. The study aimed to determine this knowledge and to describe which variables were associated with gaps in knowledge.

Methods

An anonymous online survey of healthcare workers in the field of HIV was conducted in August/September 2020. The survey was designed, tested and piloted, and included sections on demographics, guideline access and training, interaction knowledge, counselling and the effect of COVID‐19. Dissemination was via e‐mail and social media (convenience sampling). Descriptive and inferential analysis was done using proportions and the 95% confidence interval to determine relationships between independent and dependent variables. Research ethics approval was obtained from the University of Cape Town's Human Research Ethics Committee (HREC Ref: 357/2020).

Results and discussion

In total, 1950 survey responses were included in the analysis – 47.1% nurses, 35.8% doctors and 8.9% pharmacists. When asked whether they were aware that dolutegravir has interactions, 70% said yes, 13.9% said no and 16.1% did not answer. Knowledge of specific interactions and the dosing changes needed was low with a wide range between different drugs: 79.7% knew to double the dolutegravir dose with rifampicin, but with calcium, 5.1% picked both correct dosing options and 33.7% picked one of the two correct options. Access to guidelines and training were positively associated with drug interaction knowledge.

Conclusions

There are gaps in the awareness and knowledge of dolutegravir interactions and how to adjust dosing among South African healthcare workers.
Optical Pulse Compression Assisted by High‐Q Time‐Modulated Transmissive Metasurfaces
Authors: Barati Sedeh Hooman , Salary Mohammad Mahdi , Mosallaei Hossein
Published: March 2022

In this paper, based on the recently introduced concept of time‐varying media, an alternative approach is presented for controlling the compression ratio of an optical pulse in the near‐infrared regime via two all‐dielectric transmissive metasurfaces consisting of a zigzag array of silicon‐based elliptical nanodisks. Upon introducing in‐plane asymmetries and under normal incidence, the supported symmetry‐protected bound‐state in the continuum resonant mode collapses into two Fano resonances, which can be spectrally overlapped to satisfy the first Kerker's condition. To acquire an amplified signal, the desired chirp is applied to the incident pulse via a purely temporal waveform that modulates the optical response of the first layer, while the required group delay dispersion is imparted to the phase‐modulated pulse by the second metasurface in order to compress its temporal distribution. Following such a configuration, the temporal duration of the output pulse decreases from 25 to 15 ps, leading to a peak intensity enhancement of 50%. On account of time‐varying features of the first metasurface, the instantaneous frequency of the chirped light can be controlled dynamically, giving rise to the active tuning of the peak intensity from 0% up to 200%.
Single‐Photon Nonreciprocity with an Integrated Magneto‐Optical Isolator
Authors: Ren Shang‐Yu , Yan Wei , Feng Lan‐Tian , Chen Yang , Wu Yun‐Kun , Qi Xiao‐Zhuo , Liu Xiao‐Jing , Cheng Yu‐Jie , Xu Bo‐Yu , Deng Long‐Jiang , Guo Guang‐Can , Bi Lei , Ren Xi‐Feng
Published: March 2022

Nonreciprocal photonic devices are essential components of classical optical information processing. It is interesting and important to investigate their feasibility in the quantum world. In this work, a single‐photon non‐reciprocal dynamical transmission experiment has been performed with an on‐chip silicon nitride (SiN)‐based magneto‐optical (MO) isolator. The measured isolation ratio for single photons achieved is 12.33 dB, consistent with the result of the classical test, which proves the functionality of our on‐chip isolator. The quantum coherence of the passing single photons is further verified using high‐visibility quantum interference. This work will promote on‐chip nonreciprocal photonic devices within the integrated quantum circuits and help introduce novel phenomena in quantum information processes.
High‐Power Laser Systems
Authors: Zuo Jiexi , Lin Xuechun
Published: March 2022

High‐power laser sources are widely used in industrial precision processing and act as a new platform for strong‐field physics research using peak power over petawatt. This review focuses on realizing high‐energy solid‐state disk and slab systems and the nonlinear‐suppression strategies for high‐power fiber systems using the functional fibers. First, the implementations and enabling technologies of the solid‐state lasers for increasing peak power from gigawatt to petawatt are reviewed. Then the mechanisms and suppression strategies of the deterioration effects (including stimulated Raman scattering, stimulated Brillouin scattering, and transverse mode instability) in various fiber amplifiers are analyzed. At the same time, the mechanism and achievements of the current functional fibers are introduced. Finally, the challenges and perspectives of high‐power solid‐state and fiber amplifiers are summarized.
Comparative analysis and interrelation between haematite suspension based sliders of various configurations influenced with squeeze effects and film ratio under slip conditions
Authors: Ram Paras , Kumar Anil , Devender
Published: March 2022

The rationale of the current article is to investigate hematite suspension based slider bearings of various configurations namely, inclined, secant, exponential, convex and parallel pad stators under the effect of polarization force. The comparative investigation of the load capacity with reference to the position of centre of pressure under varying squeeze and slip conditions has been carried out. The squeeze velocity seems when the upper pad moves normally towards the lower one. The mathematical articulations for non‐dimensional pressure, load capacity and position of the centre of pressure for various configurations of bearing have been acquired. The optimum values of film ratio concerning maximum load capacity for various designed sliders are analyzed at distinct values of squeeze velocity. The interrelation between parallel, inclined and convex pad stator slider bearings is also explored. Finally, a suggestive approach is made to use a particular design of slider under given dynamic conditions.
A dynamic SBM‐DEA and portfolio formation test approach to the operating efficiency‐stock returns nexus
Authors: Atta Mills Ebenezer Fiifi Emire , Anyomi Siegfried , Baafi Mavis Agyapomah , Borah Prasad Siba
Published: March 2022

This study assesses operating efficiency and its drivers in China's inefficient publicly traded real estate companies via dynamic slack‐based measure data envelopment analysis and panel regression techniques. This paper also investigates operating efficiency as a company characteristic impacting stock returns using a portfolio formation test. The results indicate that only 27 out of 106 listed real estate companies are operationally efficient. Return on assets, capital structure, higher education, and institutional ownership positively and significantly impact operating efficiency. The reward of an increase in operating efficiency is seen in its positive influence on stock returns. Listed real estate companies should improve the efficiency of their operational activities to generate higher stock returns.