bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of saliva with oral and nasopharyngeal swabs for SARS‐CoV‐2 detection on various commercial and laboratory‐developed assays
Authors: Labbé Annie‐Claude , Benoit Patrick , Gobeille Paré Sarah , Coutlée François , Lévesque Simon , Bestman‐Smith Julie , Dumaresq Jeannot , Lavallée Christian , Houle Claudia , Martin Philippe , Mak Anton , Gervais Philippe , Langevin Stéphanie , Jacob‐Wagner Mariève , Gagnon Simon , St‐Hilaire Manon , Lussier Nathalie , Yechouron Ariane , Roy David , Roger Michel , Fafard Judith
Published: April 2021

The accurate laboratory detection of the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is a crucial element in the fight against coronavirus disease 2019 (COVID‐19). Reverse transcription‐polymerase chain reaction testing on combined oral and nasopharyngeal swab (ONPS) suffers from several limitations, including the need for qualified personnel, the discomfort caused by invasive nasopharyngeal sample collection, and the possibility of swab and transport media shortage. Testing on saliva would represent an advancement. The aim of this study was to compare the concordance between saliva samples and ONPS for the detection of SARS‐CoV‐2 on various commercial and laboratory‐developed tests (LDT). Individuals were recruited from eight institutions in Quebec, Canada, if they had SARS‐CoV‐2 RNA detected on a recently collected ONPS, and accepted to provide another ONPS, paired with saliva. Assays available in the different laboratories (Abbott RealTime SARS‐CoV‐2, Cobas® SARS‐CoV‐2, Simplexa™ COVID‐19 Direct, Allplex™ 2019‐nCoV, RIDA®GENE SARS‐CoV‐2, and an LDT preceded by three different extraction methods) were used to determine the concordance between saliva and ONPS results. Overall, 320 tests were run from a total of 125 saliva and ONPS sample pairs. All assays yielded similar sensitivity when saliva was compared to ONPS, with the exception of one LDT (67% vs. 93%). The mean difference in cycle threshold (∆C
t) was generally (but not significantly) in favor of the ONPS for all nucleic acid amplification tests. The maximum mean ∆​​​​​C
t was 2.0, while individual ∆C
t varied importantly from −17.5 to 12.4. Saliva seems to be associated with sensitivity similar to ONPS for the detection of SARS‐CoV‐2 by various assays.
In vitro evaluation of physicochemical variables on the nematophagous fungus Duddingtonia flagrans
Authors: Céspedes‐Gutiérrez Elizabeth , Aragón‐Novoa Diana M. , Gómez‐Álvarez Martha I. , Cortés‐Rojas Diego F.
Published: April 2021

Duddingtonia flagrans is a biological alternative to the use of anthelmintic drugs in ruminants. This fungus must be ingested by the animal, pass through the cavities of the digestive tract and reach the feces where it develops traps that capture the nematodes. The severe conditions encountered in this process negatively affect the fungus, which is reflected in the low recovery rates compared to the amount administered. The aim of this study was to evaluate independently the in vitro effect of typical physical and chemical conditions of the gastrointestinal cavities of ruminants on the concentration, viability, and the in vitro nematode predatory ability of the chlamydospores of D. flagrans. The factors evaluated individually were pH (2, 6, and 8), temperature (28 ± 2°C and 39 ± 2°C), exposure to artificial saliva, and milling. The results showed that the concentration and viability of D. flagrans were not affected by the action of pH, temperature, milling, or exposure to artificial saliva. Regarding the in vitro nematode predatory ability, a reduction was observed after the milling process and the exposure for 24 h at different pH.
Regional analysis of drought severity‐duration‐frequency and severity‐area‐frequency curves in the Godavari River Basin, India
Authors: Satish Kumar Kuruva , AnandRaj Pallakury , Sreelatha Koppala , Sridhar Venkataramana
Published: April 2021

India is one of the most drought‐ravaged countries in the world and faces at least one drought in one region or another in every 3 years. There is no single reliable approach in characterizing future droughts. To understand future drought risk, potential changes of drought properties and characteristics are analysed in this study. Using Fuzzy c‐means clustering approach, homogeneous drought regions are identified in the Godavari river basin and therefore, optimum number of clusters were assigned as four. The 12‐month standardized precipitation index (SPI) using precipitation data from India Meteorological Department (IMD) and Global Climate Model (GCM)—MIROC‐ESM‐CHEM is calculated for the homogeneous regions of the Godavari basin. The best fit copula for observed and simulated severity and duration are: Region 1—Clayton, Regions 2 and 3—Gumbel, Region 4—Frank copula. Severity‐duration‐frequency (SDF) and severity‐area‐frequency (SAF) curves were developed and analysed using the best fit copulas. The research findings conclude that moderate and severe droughts are frequently increasing for future periods (2006–2099) compared to the historic period (1962–2005). Droughts with high severity and high mean interarrival time are observed as expected in the future. For the Godavari basin, the SDF curves were concave upwards indicating an increase in severity with an increase in duration. The rate of increase of severity is small for shorter durations compared to that of longer‐duration drought. Thus, more prolonged drought events in the 21st century are likely to occur. The SAF curves with steeper slopes and high variability in topographical and hydrological characteristics have been observed over the Godavari basin. From these curves, for a specified percentage of area and return period, the drought severity can be calculated and the information can be used for crop management and agricultural water demands. Overall, the findings of this research offer a view of likely scenarios of drought in the Godavari basin.
Axillary response rates to neoadjuvant chemotherapy in breast cancer patients with advanced nodal disease
Authors: Goel Neha , Yadegarynia Sina , Rodgers Steve , Kelly Kristin , Collier Amber , Franceschi Dido , Moller Mecker , Avisar Eli , Kesmodel Susan B.
Published: April 2021

Purpose

Utilization of sentinel lymph node biopsy (SLNB) in breast cancer patients with positive nodes after neoadjuvant chemotherapy (NAC) has increased. We examine axillary response rates after NAC in patients with clinical N2‐3 disease to determine whether SLNB should be considered.

Methods

Breast cancer patients with clinical N2‐3 (AJCC 7th Edition) disease who received NAC followed by surgery were selected from our institutional tumor registry (2009–2018). Axillary response rates were assessed.

Results

Ninety‐nine patients with 100 breast cancers were identified: 59 N2 (59.0%) and 41 (41.0%) N3 disease; 82 (82.0%) treated with axillary lymph node dissection (ALND) and 18 (18.0%) SLNB. The majority (99.0%) received multiagent NAC. In patients undergoing ALND, cCR was observed in 20/82 patients (24.4%), pathologic complete response (pCR) in 15 patients (18.3%), and axillary pCR in 17 patients (20.7%). In patients with a cCR, pCR was identified in 60.0% and was most common in HER2+ patients (34.6%).

Conclusion

In this analysis of patients with clinical N2‐3 disease receiving NAC, 79.3% of patients had residual nodal disease at surgery. However, 60.0% of patients with a cCR also had a pCR. This provides the foundation to consider evaluating SLNB and less extensive axillary surgery in this select group.
Layer‐Dependent Electronic and Optical Properties of 2D Black Phosphorus: Fundamentals and Engineering
Authors: Zhang Guowei , Huang Shenyang , Wang Fanjie , Yan Hugen
Published: April 2021

In 2D materials, the quantum confinement and van der Waals‐type interlayer interactions largely govern the fundamental electronic and optical properties, and the dielectric screening plays a dominant role in the excitonic properties. This suggests strongly layer‐dependent properties and a central topic is to characterize and control the interlayer interactions in 2D materials and heterostructures. Black phosphorus is an emerging 2D semiconductor with unusually strong interlayer interactions and widely tunable direct bandgaps from the monolayer to the bulk, offering an ideal platform to probe the layer‐dependent properties and the crossover from 2D to 3D (i.e., the scaling effects). In this review, a comprehensive and thorough summary of the fundamental physical properties of black phosphorus is presented, with a special focus on the layer‐dependence character, including the electronic band structures, optical absorption and photoluminescence, and excitonic properties, as well as the band structure engineering by means of electrical gating, strain, and electrochemical intercalation. Finally, an outlook is given for the future research.
Relationship between Rockwell hardness and pearlite lamellar spacing of hardened layer under different cooling rates for U75 V 60 kg m−1 heavy rail
Authors: Kang H. , Wang Z.H. , Li Y.Y. , Li C.N.
Published: April 2021

In this study, the heat treatment processes for U75 V heavy rail were studied systematically. Further, a simple and convenient method for measuring pearlite average lamellar spacing in steel by electron probe analysis is introduced, which can make the results closer to the real pearlite average lamellar spacing. This method was used to measure the pearlite average lamellar spacing at different positions of rail head under different heat treatments. Furthermore, the relationship between pearlite average lamellar spacing and Rockwell hardness of U75 V rail steel was determined. This study will provide important theoretical guidance for the formulation of rail heat treatment processes and the measurement of pearlite average lamellar spacing in steel.
Influence of contour scans on surface roughness and pore formation using Scalmalloy® manufactured by laser powder bed fusion (PBF‐LB)
Authors: Reiber T. , Rüdesheim J. , Weigold M. , Abele E. , Musekamp J. , Oechsner M.
Published: April 2021

The scandium modified aluminium alloy Scalmalloy® is specifically developed for the use in laser‐based powder bed fusion (PBF‐LB). It is supposed to show potential in the production of lightweight structures due to its high specific strength compared to other aluminium alloys. A limiting factor is the high surface roughness of additively manufactured parts, which has a negative influence on its mechanical properties, especially under cyclic loads. In order to reduce the surface roughness, methods of design of experiments (DoE) are applied to develop contour parameters. Additionally, the formation of pores in keyhole‐mode welding and strategies to reduce the porosity in the contour area are investigated. The surface roughness of vertical walls can be reduced down to Ra < 7 μm using contour scans with a line energy EL >0.9 J mm−1 but keyhole pores start to form applying EL >0.6– 0.75 J mm−1. Two contour parameter sets in different EL‐ranges are developed that can be used to reduce the surface roughness compared to parameter sets without contour scans, without increasing the porosity in the contour area. Their impact on the mechanical properties has to be further investigated.
Influence of nanoparticle shapes on natural convection flow with heat and mass transfer rates of nanofluids with fractional derivative
Authors: Madhura K.R. , Atiwali Babitha , Iyengar S.S.
Published: April 2021

Nanofluids are gaining extensive attention due to their thermo‐physical properties in technological and industrial fields for controlling the effects of heat transfer. Classical nanofluid studies are generally confined to models described by partial differential equations of an integer order where the memory effect and hereditary properties of materials are neglected. In order to overcome these downsides, the present work focuses on studying nanofluids with fractional derivative formed by differential equations with Caputo time derivatives that provides memory effect on nanofluid characteristics. Also, investigation on natural convective flow, heat, and mass transfer of nanofluids formed by different base fluids with different shapes of copper nanoparticles past an infinite vertical plate with radiation effect is carried out. The governing fractional differential equations are solved by employing Laplace transform technique with suitable boundary conditions. The different base fluids—water (H2O), SA:sodium alginate (C6H9Na O7), and EG:ethylene glycol (C2H6O2) and different shapes of nanoparticles—blade, brick, platelet, and cylinder are considered for the study. The exact solutions are obtained for the temperature, concentration, and velocity distributions and the respective Nusselt number, Sherwood number, and skin‐friction coefficient. The influence of non‐dimensional parameters provides physical interpretations of temperature, concentration, and velocity fields, Nusselt number, Sherwood number, and skin friction in detail with the help of graphical representations. From the results, it is found that nanofluid with water‐based blade‐shaped nanoparticle exhibits more velocity and temperature distributions. Also, strengthen of fluid flow, temperature, and concentration of nanofluids are inversely correlate with fractional order derivatives.
Non‐instantaneous impulsive fractional integro‐differential equations with proportional fractional derivatives with respect to another function
Authors: Abbas Mohamed I.
Published: April 2021

This paper concerns the existence and uniqueness of solutions of non‐instantaneous impulsive fractional integro‐differential equations with proportional fractional derivatives with respect to another function. By the aid of the nonlinear alternative of Leray‐Schauder type and the Banach contraction mapping principle, the main results are demonstrated. Two examples are inserted to illustrate the applicability of the theoretical results.
Metabolic Fate and Cardiometabolic Effects of Phenolic Compounds from Red‐Fleshed Apple in Hypercholesterolemic Rats: A Comparative Study with Common White‐Fleshed Apple. The AppleCOR Study
Authors: Yuste Silvia , Ludwig Iziar A. , Romero María‐Paz , Piñol‐Felis Carme , Catalán Úrsula , Pedret Anna , Valls Rosa M. , Fernández‐Castillejo Sara , Motilva María‐José , Macià Alba , Rubió Laura
Published: April 2021

The present study aims to investigate the metabolic fate and the cardiometabolic effects of phenolic compounds provided by a red‐fleshed apple variety biofortified in anthocyanins (ACN). Wistar rats are fed with high‐fat diet (HFD) to induce hypercholesterolemia and supplemented with red‐fleshed apple (HFD+R), white‐fleshed apple (HFD+W), or an ACN‐rich infusion from aronia fruit (HFD+A) providing matched content and profile of ACN. Plasma biochemical parameters, histological analysis, and phenol biological metabolites are determined. Plasma, urine, and feces show a significant increase of ACN metabolites after HFD+R and HFD+A, while flavan‐3‐ols are significantly increased after HFD+W and dihydrochalcones derivatives increased after both apples supplementation. A cardioprotective effect is observed after both apples and aronia infusion supplementation in the reduction of aortic thickness. The kidney function is improved after all supplementations and a decrease in insulin plasma concentration after both apples supplementation (HFD+R and HFD+W) is also observed. The findings support that ACN without apple matrix can induce cardioprotective effects. ACN or flavan‐3‐ols, together with dihydrochalcones, compose a phenolic phytocomplex in red‐ and white‐fleshed apples, respectively, which can act synergistically in the attenuation of cardiovascular outcomes in hypercholesterolemic rats.
MYH9 disorder: Identification and a novel mutation in patients with macrothrombocytopenia
Authors: Natesirinilkul Rungrote , Sosothikul Darintr , Komwilaisak Patcharee , Pongtanakul Bunchoo , Narkbunnum Nattee , Yudhasompop Najwa , Mekjarusgool Pimsiri , Niparuck Pimjai , Boonyawat Kochawan , Kunishima Shinji , Sirachainan Nongnuch ,   Thai Macrothrombocytopenia Study Group
Published: April 2021

The diagnosis of MYH9 disorder is guided by recognizing granulocyte Döhle body‐like inclusion bodies and large/giant platelets in the peripheral blood smear. Immunofluorescence study of nonmuscle myosin heavy chain IIA is a sensitive screening method for diagnosis of MYH9 disorder. The diagnosis can then be confirmed by genetic analysis. A total of 67 patients with macrothrombocytopenia were included, of which 11 patients (16%), aged 4 months to 22 years, were ultimately diagnosed with MYH9 disorder. One novel mutation in exon 30 at c.4338T>C (p.F1446A) was detected. This mutation was associated with nonhematologic manifestations presenting in late adolescence with cataracts, hearing loss, and hematuria.
Hard Light for Material Inspection, Crystallography, and Much More
Authors: McCarthy Emma
Published: April 2021

This article discusses four applications for ultraviolet light, material inspection and characterization, plasma characterization, solar physics, and crystallography, and how each of these subcategories can be utilized to determine different properties within each application. This article also touches on the specific technology required for each of these applications, and subsequently each wavelength subcategory within that.
Improved cancer coping from a web‐based intervention for prostate cancer survivors: A randomized controlled trial
Authors: Tagai Erin K. , Miller Suzanne M. , Hudson Shawna V. , Diefenbach Michael A. , Handorf Elizabeth , Bator Alicja , Marziliano Allison , Kutikov Alexander , Hall Simon J. , Vira Manish , Schwartz Michael , Kim Issac Yi , Kim Sung
Published: April 2021

Objectives

Prostate cancer (PCa) survivors report poor physical functioning alongside negative psychological outcomes as they cope with treatment side effects and practical concerns after treatment completion. This study evaluated PROGRESS, a web‐based intervention designed to improve adaptive coping among PCa survivors.

Methods

Localized PCa patients (N = 431) within one year of treatment completion were randomized to receive educational booklets or PROGRESS + educational booklets. Surveys completed at baseline, 1‐, 3‐, and 6‐months assessed patient characteristics; functional quality of life and coping (primary outcomes); and psychosocial outcomes (e.g., self‐efficacy, marital communication; secondary outcomes). Intent‐to‐treat and as‐treated analyses were completed to assess change in outcomes from baseline to 6 months using linear mixed effects regression models.

Results

In the intent‐to‐treat analyses, participants randomized to the intervention group had improved diversion coping (i.e., healthy redirection of worrying thoughts about their cancer), but more difficulties in marital communication (ps < 0.05). However, PROGRESS usage was low among those randomized to the intervention group (38.7%). The as‐treated analyses found PROGRESS users reported fewer practical concerns but had worse positive coping compared to PROGRESS non‐users (ps < 0.05).

Conclusions

The findings suggest PROGRESS may improve certain aspects of adaptive coping among PCa survivors that use the website, but does not adequately address the remaining coping and psychosocial domains. Additional research is needed to better understand the gaps in intervention delivery contributing to low engagement and poor improvement across all domains of functional quality of life and adaptive coping.
Ten rules for ordering chest CTs
Authors: Brody Alan S. , Guillerman R. Paul
Published: April 2021

These “rules” are suggestions for clinicians who order chest computed tomography (CTs). The first three address CT scanning technique and the ordering details that we find cause the most confusion. The next three are on patient preparation, and specifically the use of sedation and anesthesia. Radiation risk is next, and we end with three, more philosophical, rules on how we can best work together as clinicians and imagers. This is not a complete or systematic review. You won't find detailed references (or any references for that matter), descriptions of the latest techniques, or lists of sample protocols. We hope that the reader will consult his or her imaging colleagues when more specific guidance is needed. The goal of this article is to provide simple answers to frequently asked questions and to address some of the concerns that arise when deciding how to perform a chest CT scan in a child. These are the opinions of the authors, two pediatric radiologists with special interest in chest imaging and 50 years combined experience in working with clinical colleagues to provide the best imaging care for their patients. We hope that sharing these thoughts will help to decrease confusion and increase understanding to the benefit of the children we serve.
Synthesis, Characterization, and Optical Properties of New Organic–Inorganic Hybrid Perovskites [(NH3)2(CH2)3]CuCl4 and [(NH3)2(CH2)4]CuCl2Br2
Authors: Abdel-Aal Seham K. , Kandeel Mohamed F. , El-Sherif Ashraf F. , Abdel-Rahman Ahmed S.
Published: April 2021

Organic–inorganic hybrid perovskites (OIHs) are exceptionally promising sector of novel materials for optoelectronic applications. Herein, the OIHs of the formula [(NH3)2(CH2)3]CuCl4 labeled by C3CuCl and [(NH3)2(CH2)4]CuCl2Br2 labeled by C4CuClBr are prepared by slow evaporation method. The synthesis process is achieved by mixing equimolar ethanolic solutions ratios (1:1) of their basic components (organic/inorganic). Characterizations of these materials using microchemical analysis, energy dispersion X‐ray (EDX) and X‐ray diffraction (XRD) are discussed. The XRD is used to estimate the crystalline size for prepared compounds and found in the range of 38.8 and 48.8 nm for C3CuCl and C4CuClBr, respectively. The vibrational spectra are studied by Fourier transformation infrared spectroscopy (FTIR) and show the major diffraction peaks of compounds and their assignment. UV‐region strong absorption is clarified in the optical properties studied for Cu hybrid, whereas the bandgap energy estimated via Kubelka–Munk equation and found 2.8 and 3.85 eV for C3CuCl and C4CuClBr, respectively.
Structure Investigation by Neutron Diffraction and X‐Ray Diffraction of Graphene Nanocomposite CuO–rGO Prepared by Low‐Cost Method
Authors: Abdel-Aal Seham K. , Beskrovnyi Anatolii I. , Ionov Andrey M. , Mozhchil Rais N. , Abdel-Rahman Ahmed S.
Published: April 2021

Herein, graphene nanocomposite of CuO–rGO is synthesized by simple precipitation reaction. Characterization by different techniques confirms the reduction of graphene oxide and formation of CuO–rGO. The CuO nanocrystals are uniformly distributed on graphene sheets. Neutron and X‐ray diffraction (XRD) prove the formation of single phase of CuO monoclinic crystal system with space group C2/c. Infrared spectroscopy shows vibration modes of graphene and CuO. Morphological characterization is carried out by scanning electron microscope (SEM) (SEM) and transmission electron microscope (TEM). It shows that the particle size ranges from 20 to 60 nm in which confirmed by four different theoretical approaches calculated from XRD peaks broadening data. The electronic properties using X‐ray photoelectron spectroscopy are also provided.
Application of a “Continuous‐Acquisition‐Method” to potassium isotope measurements by multi‐collector inductively coupled plasma mass spectrometry
Authors: Gu Hai‐Ou , Sun He , Huang Chao , Wang Fangyue , Ge Can
Published: April 2021

Rationale

The very small mass difference between 41K and 40ArH+ makes the flat, hydride interference‐free peak shoulders very narrow (0.002–0.003 m/z unit), bringing a number of analytical challenges when measuring K isotopic compositions by multi‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS). In traditional Sequence Run mode, the parameters are loaded every line of the sequence which can introduce tiny drifts of tune parameters and mass peaks. This may occasionally lead to the failure of K isotope measurements when mass drifts exceed 0.002 m/z unit. It is thus essential to keep the tune parameters, especially the magnet current, very stable to achieve high‐precision K isotopic compositions.

Method

We developed a “Continuous‐Acquisition‐Method” (CAM) MC‐ICP‐MS Run mode to improve the stability when determining K isotopes. Two sets of experiments were designed: (a) Stability test: measuring a single pure K solution (viz. NIST‐999c) for ~3 h and comparing the stability of the two run modes; and (b) GSB‐K test: measuring our inhouse pure K standard solution (GSB‐K) in both run modes and comparing the accuracy and precision.

Results

The traditional Sequence Run mode only kept the MC‐ICP‐MS system stable for the first ~1.5 h during the ~3‐h test, with an offset of the mass peaks of ~0.003 m/z unit. The CAM Run mode yielded higher stability during the whole test (~3 h), with a peak shift <0.0004 m/z unit. Measurement of the GSB‐K standard solution in Sequence Run and CAM Run modes gives identical δ41K values when the magnet was kept stable, with the CAM Run mode offering a better precision and keeping the instrument stable for longer time.

Conclusions

The MC‐ICP‐MS CAM Run mode shows higher stability and better precision. It is, therefore, good for high‐precision K isotope measurements.
A predefined‐time first‐order exact differentiator based on time‐varying gains
Authors: Aldana‐López Rodrigo , Gómez‐Gutiérrez David , Trujillo Miguel A. , Navarro‐Gutiérrez Manuel , Ruiz‐León Javier , Becerra Hector M.
Published: April 2021

Recently, a first‐order differentiator based on time‐varying gains was introduced in the literature, in its nonrecursive form, for signals having a second‐order derivative bounded by a known time‐varying function, where such time‐varying bound has a logarithmic derivative bounded by a known constant. It has been shown that such differentiator is globally finite‐time convergent. In this article, we redesign such an algorithm, using time base generators (a class of time‐varying gains), to obtain a differentiator algorithm for the same class of signals, but with guaranteed convergence before a desired time, that is, with fixed‐time convergence with an a priori user‐defined upper bound for the settling time. Thus, our approach can be applied for scenarios under time‐constraints. We present numerical examples exposing the contribution with respect to related state‐of‐the‐art algorithms.
Climate shocks and poverty persistence: Investigating consequences and coping strategies in Niger, Tanzania, and Uganda
Authors: Diwakar Vidya , Lacroix Antoine
Published: April 2021

This study investigates key correlates of poverty persistence and the consequences and coping strategies of climate‐induced shocks and stressors in Niger, Tanzania, and Uganda. It relies on household panel data merged with data on subnational disasters across the three countries and employs multiple measures to capture disaster prevalence of droughts, floods, and epidemics, recorded variably at the household and subnational levels. Multivariate regression analysis uncovers that environment shocks prolong poverty through direct biophysical impacts but also indirectly through various negative consequences and distress coping mechanisms in which vulnerable households engage. These include reduced food consumption and food insecurity and reduced asset values. While subnationally there are positive undercurrents, through relief aid and other forms of support that could help protect or replace assets, at the micro‐level, the results suggest that many households may survive through migration and local remittances to complement household welfare. Ensuring a supportive financial environment for poor households in these contexts, alongside risk‐informed policy and programming, would help alleviate key stressors that keep households persistently under the poverty line in contexts of climate‐induced shocks and stressors.
Solution‐Processed Semitransparent CZTS Thin‐Film Solar Cells via Cation Substitution and Rapid Thermal Annealing
Authors: Leow Shin Woei , Li Wenjie , Tan Joel Ming Rui , Venkataraj Selvaraj , Tunuguntla Venkatesh , Zhang Mengyuan , Magdassi Shlomo , Wong Lydia Helena
Published: April 2021

Semitransparent solar cells are able to capitalize on land scarcity in urban environments by co‐opting windows and glass structures as power generators, thereby expanding the capacity of photovoltaics to meet energy needs. To be successful, devices must be efficient, possess good visual transparency, long‐term stability, and low cost. Copper zinc tin sulfide is a promising thin‐film material that consists of earth‐abundant elements. For optical transparency, the usual molybdenum back contact is replaced with a transparent conducting oxide (TCO). However, due to subsequent high‐temperature annealing, the TCO degrades, losing conductivity, or forms a poor interface with CZTS. Lower temperatures mitigate this issue but hinder grain growth in CZTS films. Herein, cadmium substitution and silver and sodium doping are used to aid grain growth and improve film quality at lower annealing temperatures. Thin molybdenum is sputtered on TCO to help improve the interface transition postannealing by conversion to MoS2. Rapid thermal processing is used to minimize high‐temperature exposure time to preserve the TCO. With these methods, a semitransparent device with a front illumination efficiency of 2.96% is demonstrated.
Modelling gendered innovation for the security of energy services in poor urban environments
Authors: Batinge Benjamin , Musango Josephine Kaviti , Ceschin Fabrizio , Ambole Amollo , Smit Suzanne , Petrulaityte Aine
Published: April 2021

The security of energy services remains a challenge in poor urban Africa. Many households lack adequate energy technological devices to match modern energy carriers to fulfil their energy service needs. Females are most affected because of the culturally embedded gender roles at the household level. Despite the disproportionate gender roles in energy services, gender dimensions remain covert in the energy products innovation process. The study explored how gendered innovation augments energy innovation and addresses the problem relating to the security or fulfilment of energy services of households in poor urban environments. The study used system dynamics modelling to define the dynamic feedback loops, encompassing the security of energy services, households in poor urban environments, and gendered innovation. The results show that a gender‐sensitive, user‐centric innovation can help fulfil household energy services. The template model will be customised and applied in two poor urban environments in South Africa.
Recent Advances in Transition‐metal‐catalyzed C−C Bond Formation via C(sp2)−F Bond Cleavage
Authors: Fu Liyan , Chen Qiang , Nishihara Yasushi
Published: April 2021

The activation of a carbon‐fluorine bond is one of the most challenging topics in modern synthetic organic chemistry due to their low reactivity compared to other carbon‐halogen bonds. In this review, we present the recent developments since 2015 on cross‐coupling reactions that form C−C bonds via cleavage of C(sp2)−F bonds. Not only the conventional activation of C(sp2)−F bonds, but also decarbonylative or carbonyl‐retentive cleavage of C(acyl)−F bonds will be introduced. This paper mainly describes new protocols for the formation of C(sp2)−C(sp3), C(sp2)−C(sp2), and C(sp2)−C(sp) bonds via transition‐metal‐catalyzed cleavage of C(sp2)−F bonds.
Using cardiac ionic cell models to interpret clinical data
Authors: Corrado Cesare , Avezzù Adelisa , Lee Angela W. C. , Mendoca Costa Caroline , Roney Caroline H. , Strocchi Marina , Bishop Martin , Niederer Steven A.
Published: April 2021

For over 100 years cardiac electrophysiology has been measured in the clinic. The electrical signals that can be measured span from noninvasive ECG and body surface potentials measurements through to detailed invasive measurements of local tissue electrophysiology. These electrophysiological measurements form a crucial component of patient diagnosis and monitoring; however, it remains challenging to quantitatively link changes in clinical electrophysiology measurements to biophysical cellular function. Multi‐scale biophysical computational models represent one solution to this problem. These models provide a formal framework for linking cellular function through to emergent whole organ function and routine clinical diagnostic signals. In this review, we describe recent work on the use of computational models to interpret clinical electrophysiology signals. We review the simulation of human cardiac myocyte electrophysiology in the atria and the ventricles and how these models are being used to link organ scale function to patient disease mechanisms and therapy response in patients receiving implanted defibrillators, \cardiac resynchronisation therapy or suffering from atrial fibrillation and ventricular tachycardia. There is a growing use of multi‐scale biophysical models to interpret clinical data. This allows cardiologists to link clinical observations with cellular mechanisms to better understand cardiopathophysiology and identify novel treatment strategies.

This article is categorized under:

Cardiovascular Diseases > Computational Models

Cardiovascular Diseases > Biomedical Engineering

Cardiovascular Diseases > Molecular and Cellular Physiology
Comments on chiral algebras and Ω-deformations
Authors: Bobev Nikolay , Bomans Pieter , Gautason Fridrik Freyr
Published: April 2021

Abstract

Every six-dimensional $$ \mathcal{N} $$
N
= (2, 0) SCFT on R6 contains a set of protected operators whose correlation functions are controlled by a two-dimensional chiral algebra. We provide an alternative construction of this chiral algebra by performing an Ω-deformation of a topological-holomorphic twist of the $$ \mathcal{N} $$
N
= (2, 0) theory on R6 and restricting to the cohomology of a specific supercharge. In addition, we show that the central charge of the chiral algebra can be obtained by performing equivariant integration of the anomaly polynomial of the six-dimensional theory. Furthermore, we generalize this construction to include orbifolds of the R4 transverse to the chiral algebra plane.
Structure of flavor changing Goldstone boson interactions
Authors: Sun Jin , Cheng Yu , He Xiao-Gang
Published: April 2021

Abstract

General flavor changing Goldstone boson (GB) interactions with fermions from a spontaneous global U(1)G symmetry breaking are discussed. This GB may be the Axion, solving the strong QCD CP problem, if there is a QCD anomaly for the assignments of quarks U(1)G charge. Or it may be the Majoron, producing seesaw Majorana neutrino masses by lepton number violation, if the symmetry breaking scale is much higher than the electroweak scale. It may also, in principle, play the roles of Axion and Majoron simultaneously as far as providing solution for the strong CP problem and generating a small Majorana neutrino masses are concerned. Great attentions have been focused on flavor conserving GB interactions. Recently flavor changing Axion and Majoron models have been studied in the hope to find new physics from rare decays in the intensity frontier. In this work, we will provide a systematic model building aspect study for flavor changing neutral current (FCNC) GB interactions in the fermion sectors, or separately in the quark, charged lepton and neutrino sectors and will identify in detail the sources of FCNC interactions in a class of beyond standard model with a spontaneous global U(1)G symmetry breaking. We also provide a general proof of the equivalence of using physical GB components and GB broken generators for calculating GB couplings to two gluons and two photons, and discuss some issues related to spontaneous CP violation models. Besides, we will also provide some details for obtaining FCNC GB interactions in several popular models, such as the Type-I, -II, -III seesaw and Left-Right symmetric models, and point out some special features in these models.
Has the origin of the third-family fermion masses been determined?
Authors: Baker Michael J. , Cox Peter , Volkas Raymond R.
Published: April 2021

Abstract

Precision measurements of the Higgs couplings are, for the first time, directly probing the mechanism of fermion mass generation. The purpose of this work is to determine to what extent these measurements can distinguish between the tree-level mechanism of the Standard Model and the theoretically motivated alternative of radiative mass generation. Focusing on the third-family, we classify the minimal one-loop models and find that they fall into two general classes. By exploring several benchmark models in detail, we demonstrate that a radiative origin for the tau-lepton and bottom-quark masses is consistent with current observations. While future colliders will not be able to rule out a radiative origin, they can probe interesting regions of parameter space.
Einsatz neuer Medien in der pädiatrischen Psychosomatik
Authors: Felnhofer A. , Fischer-Grote L.
Published: April 2021

Neue Medien wie Smartphone-Apps oder virtuelle Realitäten (VR) finden zunehmend Anwendung in der pädiatrischen Psychosomatik. In der Diagnostik liegen die Vorteile in der Erfassung von Daten im Alltag sowie in der realitätsnahen und zugleich standardisierten Erfassung mithilfe der VR. In der Behandlung lassen sich selbstadministrierte und hybride Technologien von computerassistierten und computerspielbasierten Interventionen unterscheiden, die allesamt zunehmend in der pädiatrischen Psychosomatik zum Einsatz kommen, so z. B. bei Schmerzerkrankungen, Enkopresis, chronischen Erkrankungen oder auch begleitenden Depressionen und Ängsten. Durch das Auslösen alltagsnaher Reaktionen bei gleichzeitiger maximaler Kontrolle bieten VR auch in der Forschung große Vorteile. Nichtsdestotrotz sind Kontraindikationen wie Psychosen, Epilepsie und Migräne zu beachten. Eine umfassende Schulung des Fachpersonals ist daher für die Nutzung neuer Medien in der Diagnostik, Behandlung und Forschung essenziell.
Bullying behaviours and other conduct problems: longitudinal investigation of their independent associations with risk factors and later outcomes
Authors: Ganesan Keertana , Shakoor Sania , Wertz Jasmin , Agnew-Blais Jessica , Bowes Lucy , Jaffee Sara R. , Matthews Timothy , Arseneault Louise
Published: April 2021

Purpose

Bullying behaviours and other conduct problems often co-occur. However, we do not yet know whether bullying behaviours are associated with early factors and later poor outcomes independently of conduct problems. While there are differing, specific interventions for bullying behaviours and for conduct problems, it is unclear if such specificity is justified given parallels between both behaviours.

Methods

We used prospective data from the Environmental Risk (E-Risk) Longitudinal Twin Study, a nationally representative sample of 2232 children. Mothers and teachers reported on children’s bullying behaviours and conduct problems at ages 7 and 10. We collected measures of risk factors, including temperament and family factors, when children were age 5. We assessed behavioural, emotional, educational and social problems when participants reached the ages of 12 and 18.

Results

Bullying behaviours and conduct problems co-occurred in childhood. Our findings indicated that bullying behaviours and other conduct problems were independently associated with the same risk factors. Furthermore, they were associated with the same poor outcomes at both ages 12 and 18. Despite this, bullying behaviours were uniquely associated with behavioural, emotional, educational and social problems at age 18.

Conclusions

Our findings suggest that anti-bullying programmes and interventions aimed at reducing conduct problems could benefit from greater integration. Furthermore, our study highlights the mental health problems children who bully may face in later years and the need to consider those in intervention plans.
Investigation of microstructure, mechanical and machinability properties of Mo-added steel produced by powder metallurgy method
Authors: Erden Mehmet Akif , Yaşar Nafiz , Korkmaz Mehmet Erdi , Ayvacı Burak , Nimel Sworna Ross K , Mia Mozammel
Published: April 2021

This study presents the impact of molybdenum (Mo) inclusion on microstructure, mechanical, and machinability behavior of steels manufactured with powder metallurgy (PM) approach. PM steel samples with different molybdenum ratios were pressed at 750-MPa pressing pressure and sintered in the atmosphere-controlled tube furnace at 1400°C for 1 h. While particle size and distribution of phases of PM steels with different molybdenum ratios were determined by optical microscope, mechanical properties were determined by applying tensile test. The results were observed that 3% Mo weight-added steel displayed the maximum yield and tensile strength. In addition, the machinability properties of 3% Mo-added steel, which has the highest yield and tensile strength, were investigated. In this work, we researched the thrust force and surface roughness as machinability output, and drilling parameters on the output were determined by utilizing analysis of variance. Finally, SEM images were taken from the inner surfaces of the machined holes and the fractured surfaces from tensile test, and information about the machinability of this alloy produced with PM was presented. As a result, an increase in yield and tensile strength and a reduction in strain were identified with the increase in Mo content. Moreover, the coated cutting tools are better on the machining output than the uncoated cutting tools in terms of green environment. The most important factors on the Fz and Ra are the coating condition and the feed rate with 56.53% and 43.62% PCR, respectively.
Understanding the local structure of disordered carbons from cellulose and lignin
Authors: Meng Yujie , Contescu Cristian I. , Liu Peizhi , Wang Siqun , Lee Seung-Hwan , Guo Junjie , Young Timothy M.
Published: April 2021

An electron microscopy investigation was performed to understand the relationship between the microstructure and properties of carbonized cellulose and lignin (softwood kraft lignin) relative to the structure of the original biomass components. Structure details at micro- and molecular levels were investigated by scanning transmission electron microscopy. Atomic-resolution images revealed the presence of random disordered carbon in carbonized cellulose (C-CNC) and of large domains of well-ordered carbon with graphite sheet structure in carbonized lignin (C-Lignin). These structural differences explain why C-CNC exhibits higher surface area and porosity than C-Lignin. The presence of certain well-ordered carbon in carbonized lignin indicates some of the carbon in lignin are graphitized with heat treatment temperature up to 950 °C. This result is encouraging for future endeavors of attaining acceptable modulus of carbon fiber from lignin given suitable modifications to the chemistry and structure of lignin. The results of this research contribute to an improved understanding of the carbonization mechanism of the key cellulose and lignin components of biomass materials.
On the way toward regulatable expression systems in acetic acid bacteria: target gene expression and use cases
Authors: Fricke Philipp Moritz , Klemm Angelika , Bott Michael , Polen Tino
Published: April 2021

Acetic acid bacteria (AAB) are valuable biocatalysts for which there is growing interest in understanding their basics including physiology and biochemistry. This is accompanied by growing demands for metabolic engineering of AAB to take advantage of their properties and to improve their biomanufacturing efficiencies. Controlled expression of target genes is key to fundamental and applied microbiological research. In order to get an overview of expression systems and their applications in AAB, we carried out a comprehensive literature search using the Web of Science Core Collection database. The Acetobacteraceae family currently comprises 49 genera. We found overall 6097 publications related to one or more AAB genera since 1973, when the first successful recombinant DNA experiments in Escherichia coli have been published. The use of plasmids in AAB began in 1985 and till today was reported for only nine out of the 49 AAB genera currently described. We found at least five major expression plasmid lineages and a multitude of further expression plasmids, almost all enabling only constitutive target gene expression. Only recently, two regulatable expression systems became available for AAB, an N-acyl homoserine lactone (AHL)-inducible system for Komagataeibacter rhaeticus and an l-arabinose-inducible system for Gluconobacter oxydans. Thus, after 35 years of constitutive target gene expression in AAB, we now have the first regulatable expression systems for AAB in hand and further regulatable expression systems for AAB can be expected.

Key points

• Literature search revealed developments and usage of expression systems in AAB.

• Only recently 2 regulatable plasmid systems became available for only 2 AAB genera.

• Further regulatable expression systems for AAB are in sight.
Knee articular cartilage injury treatment with matrix-induced autologous chondrocyte implantation (MACI): correlation at 24 and 120 months between clinical and radiological findings using MR arthrography
Authors: Calvi Marco , Curti Marco , Ossola Christian , Duvia Marta , Angeretti Maria Gloria , Ronga Mario , Genovese Eugenio Annibale
Published: April 2021

Objective

To evaluate the long-term evolution of matrix-induced autologous chondrocyte implantation (MACI) with magnetic resonance (MR) arthrography and verify the correlation between radiological and clinical findings.

Materials and methods

Twenty-six patients (20 m/6f) were diagnosed with knee chondral injuries and treated with MACI implantation. Each patient received MR arthrography and clinical examination at mid-term (range 22–36 months) and long term (range 96–194 months) after surgery. MR arthrography was performed with dedicated coil and a 1.5-Tesla MR unit. The modified MOCART scale was used to evaluate the status of chondral implants. Implant coating, integration to the border zone, and the surface and structure of the repaired tissue were evaluated. Presence of bone marrow oedema was evaluated. The Cincinnati Knee Rating System (CKRS) was used for clinical assessment.

Results

At long term, 4/26 patients had complete alignment; 5/26 had a complete integration of the margins; in 4/26 cases, the implant surface was undamaged; in 14/26 cases, the reparative tissue was homogeneous. In 9/26 cases, the implant showed isointense signal compared to articular cartilage, while the presence of subchondral bone oedema was documented in 19/26 cases. The average radiological score decreased from 59.2 (mid-term) to 38.6 (long term). The average clinical score decreased from 8.9 to 8.3.

Conclusions

Decrease in clinical results was not significant (0.6 pointsp = .06), but mMOCART scores decreased significantly (p = .00003). Although imaging studies showed deterioration of the grafts, the patients did not have significant clinical deterioration (231/250).