bluuebunny/crossref_metadata_2025 huggingface dataset:
Self‐compassion influences the caring behaviour and compassion competence among saudi nursing students: A multi‐university study
Authors: Alquwez Nahed , Cruz Jonas Preposi , Al Thobaity Abdulellah , Almazan Joseph , Alabdulaziz Hawa , Alshammari Farhan , Albloushi Monirah , Tumala Regie , Albougami Abdulrahman
Published: March 2021

Aim

This research investigated the perceptions of Saudi nursing students regarding self‐compassion and examined its influence on their caring behaviour and compassion competence.

Design

This is a quantitative and cross‐sectional study.

Methods

This multiuniversity study surveyed a convenience sample of 961 nursing using the Self‐compassion Scale, Compassion Competence Scale and Caring Behavior Inventory‐16 version. Standard multiple analysis was performed separately for caring behaviour and compassion competence as dependent variables. For both models, the self‐compassion dimensions and the demographic variables were considered predictor variables.

Results

The students reported their self‐compassion moderately, with mindfulness receiving the highest mean and self‐judgment receiving the lowest mean. Significant differences were observed on self‐compassion of students between universities. Caring behaviour and compassion competence were also rated moderately by the students. “Self‐kindness” and “common humanity” were identified as significant predictors of caring behaviour, whereas “self‐kindness,” “self‐judgment,” “common humanity” and “mindfulness” were significant predictors of compassion competence.
Deep Learning for Hyperbolic Conservation Laws with Non‐convex Flux
Authors: Minbashian Hadi , Giesselmann Jan
Published: March 2021

In this work, we investigate the capabilities of deep neural networks for solving hyperbolic conservation laws with non‐convex flux functions. The behaviour of solutions to these problems depends on the underlying small‐scale regularization. In many applications concerning phase transition phenomena, the regularization terms consist of diffusion and dispersion which are kept in balance in the limit. This may lead to the development of both classical and non‐classical (or undercompressive) shock waves at the same time which makes the development of approximation schemes that converge towards the appropriate weak solution of these problems challenging. Here, we consider a scalar conservation law with cubic flux function as a toy model and present preliminary results of an ongoing work to study the capabilities of a deep learning algorithm called PINNs proposed in [1] for solving this problem. It consists of a feed‐forward network with a hyperbolic tangent activation function along with an additional layer to enforce the differential equation.
Deep learning of multibody minimal coordinates
Authors: Angeli Andrea , Naets Frank , Desmet Wim
Published: March 2021

Multibody systems [1] are the state‐of‐the‐art tool to model complex mechanical mechanisms. However, they typically include redundant coordinates plus constraints, leading to differential algebraic equations for the dynamics which require dedicated integration schemes and control/estimation algorithms.

In the deep learning field, autoencoders are a particular neural network class with a symmetric structure to perform a nonlinear dimensionality reduction. In fact, they can be seen as a non‐linear extension of principal component analysis [2].

In this work, it is proposed to use an autoencoder to reduce a general multibody model to minimal coordinates, eliminating the constraints. The obtained decoder function is used to perform a non‐linear projection of the multibody coordinates:

urn:x-wiley:16177061:media:PAMM202000348:pamm202000348-math-0001

where

are respectively the encoder and decoder neural network functions, while

are respectively the obtained minimal coordinates and reconstructed full multibody coordinates.

The novelty is that the autoencoder training includes the multibody physics information [3]. In this way, the autoencoder does not only perform a dimensionality reduction of the original coordinates but can be used for model order reduction. The obtained reduced‐order model consists of ordinary differential equations (with respect to the original differential algebraic equations) and can be used to perform dynamic simulations and easily coupled with standard estimation algorithms for state‐estimation.

A typical application example is a mechanism with closed‐loops, such as a car suspension, for which no analytical expression is available to reduce the full multibody model to minimal coordinates. The introduced physics‐informed neural network allows to reduce the model and combine it with an augmented extended Kalman filtering scheme [4], in order to estimate difficult‐to‐measure inputs or parameters in the system.

In a first application, the model in combination with measured strut displacement or acceleration, allows to estimate the strut force, in addition to the body full coordinates in position, velocity and acceleration. The rationale is reported in the figure below.

rationale.png

The Flanders Innovation & Entrepreneurship Agency within the IMPROVED project and the AI impulse program of the Flemish Government are gratefully acknowledged for their support.
Multi‐fidelity data fusion for the approximation of scalar functions with low intrinsic dimensionality through active subspaces
Authors: Romor Francesco , Tezzele Marco , Rozza Gianluigi
Published: March 2021

Gaussian processes are employed for non‐parametric regression in a Bayesian setting. They generalize linear regression embedding the inputs in a latent manifold inside an infinite‐dimensional reproducing kernel Hilbert space. We can augment the inputs with the observations of low‐fidelity models in order to learn a more expressive latent manifold and thus increment the model's accuracy. This can be realized recursively with a chain of Gaussian processes with incrementally higher fidelity. We would like to extend these multi‐fidelity model realizations to case studies affected by an high‐dimensional input space but with a low intrinsic dimensionality. In this cases physical supported or purely numerical low‐order models are still affected by the curse of dimensionality when queried for responses. When the model's gradients information is provided, the presence of an active subspace can be exploited to design low‐fidelity response surfaces and thus enable Gaussian process multi‐fidelity regression, without the need to perform new simulations. This is particularly useful in the case of data scarcity. In this work we present a multi‐fidelity approach involving active subspaces and we test it on two different high‐dimensional benchmarks.
Data‐Driven Learning of Reduced‐Order Dynamics for a Parametrized Shallow Water Equation
Authors: Yıldız Süleyman , Goyal Pawan , Benner Peter , Karasözen Bülent
Published: March 2021

A non‐intrusive data‐driven model order reduction method is introduced that learns low‐dimensional dynamical models for a parametrized non‐traditional shallow water equation (NTSWE) [1]. The reduced‐order model is learnt by setting an appropriate least‐squares optimization problem [2] in a low‐dimensional subspace. The non‐intrusive model order reduction framework is extended to a parametric case using the parameter dependency at the level of the partial differential equation. The efficiency of the proposed non‐intrusive method is illustrated to construct reduced‐order models for NTSWE and compared with an intrusive method, proper orthogonal decomposition with Galerkin projection. Furthermore the predictability of both models outside the range of the training data is discussed.
Abrasive wear and dynamic–mechanical behavior of marble dust filled bagasse fiber reinforced hybrid polymer composites
Authors: Singh Tej , Puri Manish , Tejyan Sachin , Ravi Ravi Kant
Published: March 2021

The present study investigated the influence of waste materials on physico‐mechanical, dynamic mechanical, and abrasive wear behavior of polymer composites. The composites were manufactured by varying the waste bagasse fiber (2.5, 5, 7.5, and 10 wt%) in fixed marble dust (15 wt%) filled epoxy resin. The void content of the composite found to decrease, whereas density, impact energy, and flexural strength were found to increase with the increase of waste bagasse fiber loading. The hardness and tensile strength were first increased, and after attaining highest values for 7.5 wt% fiber content, both decreased with another fiber loading. Damping properties such as storage modulus, loss modulus, and damping factor were evaluated utilizing dynamic mechanical analyzer. Results showed that the composites with 10 wt% waste bagasse fiber loading exhibited highest viscoelastic properties. Moreover, the dry sand abrasive wear behavior of fabricated composites was designed to study the impact of fiber loading, sliding distance, and load using the Taguchi method. The analysis reveals that the sliding distance contributes the most toward abrasive wear of the composites, with a contribution of 58.70%. 7.5 wt% waste bagasse fiber, 400 m sliding distance, and 5 N load resulted in a most wear‐resistant combination. Finally, the abraded composite surfaces were examined using scanning electron microscopy to study the possible wear mechanisms.
Profiling and quantitation of alkaloids in different parts of Sophora alopecuroides L. extracts by high‐performance liquid chromatography with electrospray ionisation ion mobility spectrometry detection
Authors: Jia Xu , Zhang Hanghang , Jiang Xiangfu , Lu Yaling , Liu Wenjie , Yu Jianna
Published: March 2021

Introduction

Ambient pressure electrospray ionisation ion mobility spectrometry coupled to high‐performance liquid chromatography (HPLC) was used to detect alkaloids from different parts of Sophora alopecuroides L. extracts. Multiplexing ion mobility spectrometry (IMS) was used to improve the signal‐to‐noise ratio while maintaining high resolving power for the detecting of eluents from HPLC separation.

Material and methods

The alkaloids profile and distribution are demonstrated by retention time‐drift time two‐dimensional spaces, and the contents of five major alkaloids including sophoridine, sophocarpine, cytisine, aloperine, and matrine were determined in the leaf, skin, stem, seed kernel, and seed husk using the HPLC‐IMS method. This method offers extra separation ability to isomers such as matrine and sophocarpine, which can be difficult to distinguish by mass spectrometry.

Results

The reduced mobilities for cytisine, sophoridine, sophocarpine, matrine, and aloperine are 0.828, 0.718, 0.731, 0.725, and 0.769 cm2/V/s, respectively. The limits of detection are 0.553, 0.488, 0.479, 0.484, and 0.513 ug/mL. This method adds extra separation ability to HPLC to resolve co‐eluted peaks and provides another qualitative parameter besides HPLC retention time.
Characterization of nanocellulose from Indica rice straw as reinforcing agent in epoxy‐based nanocomposites
Authors: Mamat Razali Nur Amira , Ismail Muhamad Fareez , Abdul Aziz Fauziah
Published: March 2021

The extraction of nanocellulose from agro‐waste have received wide attention in nanocomposite technologies. This research unravels physico‐chemical characteristics of cellulose from Malaysia Indica rice straw, and the derived cellulose nanocrystal (CNC) by hydrochloric acid (HCl) hydrolysis. The CNC was subjected to field emission scanning electron microscopy (FESEM) and/or transmission electron microscopy (TEM) and Fourier transformed infrared (FTIR) studies. Furthermore, X‐ray diffraction (XRD) and small‐angle X‐ray scattering (SAXS) were compared with TEM for the CNC lateral crystal size. Subsequently, CNC reinforced epoxy laminates for Kevlar were prepared and tested for their tensile properties. While FTIR analysis confirmed the monoclinic cellulose structure of the isolated CNC, XRD, and SAXS were compared with TEM for the CNC lateral crystal size. Hydrolysis of the cellulose sample yielded 40.87% of CNC with 4.8 nm in width and a needle‐shaped nature. The extracted CNC has relatively low crystallinity (56.12%) but interestingly low crystallite size with an average crystallite size of 1.69 nm (XRD) and 4.18 nm (SAXS). Furthermore, an addition of just 1 wt% of CNC to epoxy composite increased the strength of Kevlar by over 300% and the elastic modulus by nearly three‐fold. Nanocellulose obtained from rice straw have great potential as reinforcing agents for the manufacture of nanocomposites.
Sodium doping of solution‐processed amine‐thiol based CIGS solar cells by thermal evaporation of NaCl
Authors: Uličná Soňa , Welch Liam M. , Abbas Ali , Togay Mustafa , Tsai Vincent , Betts Tom R. , Malkov Andrei V. , Walls John M. , Bowers Jake W.
Published: March 2021

Poor crystallinity, high degree of porosity and rough surfaces are the main drawbacks of solution‐processed CIGS absorbers resulting in lower power conversion efficiencies when compared to vacuum‐based CIGS solar cells. Therefore, promoting absorber grain growth is key to further improve solution‐based solar cell performance. The effect of alkali elements such as Na in CIGS absorbers is generally recognised to have beneficial effects not only on the absorber opto‐electronic properties but also on the grain growth. In this work, thermal evaporation of a thin layer of NaCl prior to selenisation resulted in absorbers with significantly larger CIGS grains than previously seen with Na diffusing directly from the from soda‐lime glass substrate. NaCl is non‐toxic, abundant and readily available compound that has not been typically used as an evaporation source, but rather as an additive into CIGS precursor solution. The effect of Na on these solution‐processed CIGS devices was primarily observed in the spectacular morphological changes leading to improved carrier collection and minority carrier lifetimes, but less on the absorber doping. Transmission electron microscopy (TEM) revealed voids forming around large CIGS grains upon NaCl addition and these had a negative effect on inter‐grain carrier transport. Nonetheless, the resulting device performance doubled from 5% to 10% with addition of Na using this doping approach; however, a compromise between the optimum grain growth and optimum electronic properties had to be made. This study demonstrates a novel, simple and effective Na‐doping strategy for CIGS absorbers and reveals the current limitations of the Na‐doping in solution‐processed atmospherically deposited cells.
Examining congruence in parent–teacher perceptions of middle school supports for students and families
Authors: Garbacz S. Andrew , Santiago Rachel T. , Kosty Derek , Zahn Miranda , Stormshak Elizabeth A. , Smolkowski Keith , Seeley John R.
Published: March 2021

The purpose of this study was to examine parent–teacher congruent perceptions of middle school structures to support parent monitoring of children's behavior. We examined family educational involvement and school's communication and support to families as predictors of congruence, as well as congruence as a predictor of children following school rules and expectations. Participants were 415 teachers and 5003 parents across 40 public middle schools in the northwest region of the United States. Mixed‐effects regression was used to examine the cross‐sectional data. School size and student eligibility of free or reduced price school lunch were included as school‐level covariates. Results suggested that higher levels of teacher‐reported family involvement and school communication and support to families were significantly associated with greater parent–teacher congruence. In addition, results suggested that greater parent–teacher congruence was significantly associated with higher levels of teacher‐report of children following school rules and expectations. Implications for research on parent–teacher congruence and family–school collaboration are discussed at the school system level in terms of parent monitoring of children's behavior. Practical applications are reviewed for public middle schools.
LGBTQ student experiences in schools from 2009–2019: A systematic review of study characteristics and recommendations for prevention and intervention in school psychology journals
Authors: Abreu Roberto L. , Audette Lillian , Mitchell Y'Londa , Simpson Ina , Ward Jessica , Ackerman Lindsay , Gonzalez Kirsten A. , Washington Katherine
Published: March 2021

The present systematic review analyzes ways in which empirical studies in the field of school psychology have studied the experiences of lesbian, gay, bisexual, transgender, and queer (LGBTQ) students in the past decade (2009–2019). Results from 23 studies revealed an over‐representation of quantitative studies conducted mostly in the United States and an over‐representation of majority White, cisgender, and high school participants across studies. Results also showed that studies in the last decade have: (a) focused on exploring negative attitudes and behaviors toward LGBTQ students and the outcomes of these attitudes and behaviors, (b) provided direction on how to support LGBTQ students in schools, and (c) analyzed the effects of bystanders and perpetrators on the well‐being of LGBTQ students. In addition, this review revealed ways in which studies in school psychology journals present prevention and intervention practices for creating a safe environment for LGBTQ students, including: (a) policies that focus on the inclusion and protection of LGBTQ students, (b) training for faculty and other school staff to promote LGBTQ students' safety, and (c) curriculum and extracurricular activities that address LGBTQ issues. We provide recommendations for improving the experiences of LGBTQ students in schools such as involving community stakeholders in drafting affirming policies.
What do French school staff know about young carers? A qualitative study about their perceptions
Authors: Justin Pauline , Dorard Géraldine , Vioulac Christel , Leu Agnes , Untas Aurélie
Published: March 2021

Young carers (YCs) are children and adolescents who provide a significant help to family member(s) with a disease or a disability. They often remain hidden, especially in France where awareness levels and policy responses regarding YC are just emerging. Several studies show that YC often have difficulties at school because of their situation. However, school staff seems to have difficulties to identify and support YC. The aim of this study was to explore schools teachers and other professionals' levels of awareness and their perceptions of the potential impacts of caring on pupil attainment, achievement, and wellbeing. Thirty‐three professionals working with pupils from 6 to 18 years old (primary, secondary, and high schools) took part in a semi‐structured interview and in a short phone interview. The results showed that almost all had already met a YC. Despite knowledge and perceptions of potential impacts for their pupils, few undertook actions to support them. Healthcare professionals and school counsellors seemed more aware of these situations than teachers and more prone to offer support. These results underline the need to enhance all school staff's knowledge about YC and help them develop appropriate support.
Adaptability and ‘CandidatusLiberibacter asiaticus’ titres of Diaphorina citri adults on three weed species in China
Authors: Lu Huilin , Fang Xiaoduan , Wu Fengnian , Ouyang Gecheng
Published: March 2021

BACKGROUND

Diaphorina citri is a vector of ‘Candidatus Liberibacter asiaticus’ (CLas), which is associated with citrus huanglongbing (HLB). In this study, the adaptability and CLas titres of D. citri adults on three weed species, namely, Ageratum conyzoides, Solanum nigrum and Praxelis clematidea, which are widely distributed in citrus orchards in China, were determined.

RESULTS

D. citri selected S. nigrum preferentially over the other weed species. The longest survival times of D. citri adults on A. conyzoides, S. nigrum and P. clematidea were 48, 41 and 11 days, respectively. On S. nigrum, the survivorship of females was significantly higher than that of males. The CLas titres of D. citri adults feeding on the three weeds for 1 week increased significantly during autumn but did not change significantly during spring. Conversely, the titres of adults on citrus increased significantly during spring but did not change significantly during autumn.

CONCLUSION

D. citri exhibited different adaptabilities to the three weed species, but the CLas titres of D. citri adults did not decrease on any of the weeds. These results suggested that the three weed species could help dispersing of D. citri and transmission of CLas while ideal host conditions were scarce or absent. © 2021 Society of Chemical Industry.
Phytotherapy in the management of denture stomatitis: A systematic review and meta‐analysis of randomized controlled trials
Authors: Shui Yusen , Li Jingya , Lyu Xiaoying , Wang Yan
Published: March 2021

Medicinal plant extracts are commonly applied for infectious diseases and are perceived as alternatives to conventional antimicrobial agents. We aimed to confirm the efficacy of phytotherapy for denture stomatitis compared with conventional therapies and placebo. A comprehensive literature search was conducted in Pubmed, Embase, Cochrane Library (CENTRAL), Scopus, and Web of Science, in addition to manual searching. Randomized controlled trials (RCTs) published in English, and studying the treatment of denture stomatitis with herbal medicines, were included. The outcome measures included the relief of clinical signs, reduced Candida colony counts, adverse effects, and patient satisfaction. Nineteen RCTs were included for a systematic review based on selection criteria. Two of them were analyzed using a random‐effects model. There was no difference in the relief of clinical signs (odds ratio (OR) = 0.96; 95% confidence interval (CI): 0.43–2.15) and microbiological improvement (OR = 1.74; 95% CI: 0.55–5.45) between propolis and miconazole. Most of the included studies showed that phytomedicines had fewer side effects and more patient satisfaction than antifungals or disinfectants. However, further RCTs with more standardly prepared herbal formulations are required to verify the clinical efficacy of phytotherapy as an alternative or adjunctive therapy for denture stomatitis.
Theoretical investigation of novel half Heusler compounds MRhSb (M = Nb & Ta): For optoelectronic and thermoelectric applications
Authors: Hamli Meryem , Bensaid Djillali , Benkada Amel , Bouzouira Nour eddine , Bencherif Kadour , Benzoudji Fathi
Published: March 2021

The main objective of this work is to make a detailed study on a new class of half heuslers which possess a 19 valence electron and which are sought for perpetually because of their thermoelectric performances. The mechanical, electronic structures, optical, and electrical transport properties are studied using full potential linearized augmented plane wave (LAPW) + local orbitals (lo) scheme, in the framework of density functional theory (DFT) with generalized gradient approximation (GGA) for the purpose of exchange correlation energy functional. The electronic structure is treated by the TB‐mBJ exchange‐correlation potentials. The independent elastic constants and the related mechanical properties are investigated. From the energy bands and density of states it is observed that the 3d‐states of Nb, Ta, and Rh atoms contribute mainly to the conduction band, which results in increase in electrical and thermal conductivity of NbRhSb and TaRhSb . The optical constants as the dielectric function, refractive index, optical reflectivity, and absorption coefficient were calculated and discussed in detail. The dependence of Seebeck coefficient, electrical conductivity, and power factor on the Fermi level is investigated.
Nonparametric machine learning for precision medicine with longitudinal clinical trials and Bayesian additive regression trees with mixed models
Authors: Spanbauer Charles , Sparapani Rodney
Published: March 2021

Precision medicine is an active area of research that could offer an analytic paradigm shift for clinical trials and the subsequent treatment decisions based on them. Clinical trials are typically analyzed with the intent of discovering beneficial treatments if the same treatment is applied to the entire population under study. But, such a treatment strategy could be suboptimal if subsets of the population exhibit varying treatment effects. Identifying subsets of the population experiencing differential treatment effect and forming individualized treatment rules is a task well‐suited to modern machine learning methods such as tree‐based ensemble predictive models. Specifically, Bayesian additive regression trees (BART) has shown promise in this regard because of its exceptional performance in out‐of‐sample prediction. Due to the unique inferential needs of precision medicine for clinical trials, we have proposed the BART extensions explicated here. We incorporate random effects for longitudinal repeated measures and subject clustering within medical centers. The addition of a novel interaction detection prior to identify treatment heterogeneity among clinical trial patients and its association with patient characteristics. These extensions are unified under a framework that we call mixedBART. Simulation studies and applications of precision medicine based on real randomized clinical trials data examples are presented.
An Efficient Polymer Supported Palladium Catalyst for ortho Selective C−H Olefination of Anilides
Authors: Saranya Thachora Venu , Sruthi Pambingal Rajan , Ayana Nambokkil , Anas Saithalavi
Published: March 2021

The development of a novel heterogeneous polymer supported palladium catalyst for the oxidative C−H olefination of anilides is described. The catalyst was realized by immobilizing Palladium acetate over ethylene diamine modified Polyacrylonitrile (PAN) and characterized by means of FTIR, XRD and XPS analyses which evidenced the complexation of Pd(OAc)2 with the chelating groups in the polymer. The resulting supported complex (en‐PAN‐Pd) was then explored as an efficient and reusable heterogeneous catalyst for ortho selective C−H activation of anilides on reaction with a number of alkyl acrylates. This reaction protocol serves as a useful and greener method for the synthesis of o‐alkenyl anilides under mild reaction conditions. The catalyst also exhibited good recyclability and reusability without losing much catalytic activity.
The “Chemistree” of Porous Coordination Networks: Taxonomic Classification of Porous Solids to Guide Crystal Engineering Studies
Authors: O'Hearn Daniel J. , Bajpai Alankriti , Zaworotko Michael J.
Published: March 2021

New approaches to gas/vapor storage and purification are urgently needed to address the large energy footprint, cost, and/or risk associated with existing technologies. In this context, new classes of porous physisorbents, exemplified by porous coordination networks (PCNs), have emerged. There are now >100 000 entries in the Cambridge Structural Database (CSD) metal‐organic framework (MOF) subset and the rate of publication, >5000 per year, grows unabatedly. The number of PCNs makes it infeasible to test all of them for sorption performance and it is therefore timely to introduce a classification approach based upon taxonomy to supplement topological classification of PCNs. This taxonomic approach complements existing databases such as the CSD and enable the design (crystal engineering) of new families of PCNs. It also categorizes existing PCNs in a manner useful to crystal engineers. The internal consistency of the taxonomic approach is verified by case studies of several well‐known PCNs whereas its utility is demonstrated upon understudied topologies and hard‐to‐rationalize infinite rod building blocks. Overall, taxonomic classification enables a traffic light system to direct crystal engineers towards finding a “needle in haystack,” that is, a family (platform) of PCNs that is amenable to crystal engineering and systematic structure/property studies.
Interfacial Super‐Assembly of T‐Mode Janus Porous Heterochannels from Layered Graphene and Aluminum Oxide Array for Smart Oriented Ion Transportation
Authors: Zhang Liping , Zhou Shan , Xie Lei , Wen Liping , Tang Jinyao , Liang Kang , Kong Xiangyu , Zeng Jie , Zhang Runhao , Liu Jiaqing , Qiu Beilei , Jiang Lei , Kong Biao
Published: March 2021

Salinity gradient energy existing in seawater and river water is a sustainable and environmentally energy resource that has drawn significant attention of researchers in the background of energy crisis. Nanochannel membrane with a unique nano‐confinement effect has been widely applied to harvest the salinity gradient energy. Here, Janus porous heterochannels constructed from 2D graphene oxide modified with polyamide (PA‐GO) and oxide array (anodic aluminum oxide, AAO) are prepared through an interfacial super‐assembly method, which can achieve oriented ion transportation. Compared with traditional nanochannels, the PA‐GO/AAO heterochannels with asymmetric charge distribution and T‐mode geometrical nanochannel structure shows directional ionic rectification features and outstanding cation selectivity. The resulting heterochannel membrane can achieve a high‐power density of up to 3.73 W m−2 between artificial seawater and river water. Furthermore, high energy conversion efficiency of 30.3% even in high salinity gradient can be obtained. These achievable results indicate that the PA‐GO/AAO heterochannels has significant potential application in salinity gradient energy harvesting.
Coordination Strategy Driving the Formation of Compact CuSCN Hole‐Transporting Layers for Efficient Perovskite Solar Cells
Authors: Xu Pan , Liu Jian , Huang Jiahao , Yu Fan , Zhang Rui , Li Cheng-Hui , Zheng You-Xuan , Zuo Jing-Lin
Published: March 2021

The preparation of a high‐quality CuSCN thin film is very important to guarantee its efficient performance in an electronic device. Herein, a coordination strategy is reported for the formation of a highly compact CuSCN hole‐transporting layer by retarding fast crystallization via constructing intermediate adducts, and investigated its application for perovskite solar cells (PSCs). Specifically, the strong coordination bond between CuSCN and pyridine derivate ligands results in the formation of a stable intermediate phase, which is further converted to compact CuSCN layers under thermal annealing. The configuration of the intermediate phase is demonstrated to be crucial for the subsequent assembly of high‐quality CuSCN layers and results in an improved performance of the devices. CuSCN thin films crystallized from an intermediate adduct, CuSCN‐(Cl‐Py), with a rippled sheet configuration show an exceptional surface uniformity and high hole mobility, which facilitates efficient hole extraction and suppresses charge recombination in PSCs, resulting in an enhanced device efficiency of 19.19%. That is the highest value of the inverted planar PSCs using CuSCN as a hole‐transporting layer to the best of the authors’ knowledge. This novel coordination strategy can be expected to be used in the preparation of other inorganic charge transporting materials for electronic devices.
A Coadditive Strategy for Blocking Ionic Mobility in Methylammonium‐Free Perovskite Solar Cells and High‐Stability Achievement
Authors: Zheng Daming , Zhu Tao , Pauporté Thierry
Published: March 2021

Herein, the synthesis of methylammonium‐free and bromide‐free CsxFA1−xPbI3 (FA for formamidinium) perovskite (PVK) photovoltaic layers with intrinsic outstanding properties in terms of crystallinity, defect waiving/passivation, and ionic mobility blocking by using a coadditives approach is described. It consists in mixing two chloride additives in the PVK precursor solution: potassium chloride (KCl) and ammonium chloride (NH4Cl). KCl favors the lead iodide (PbI2) precursor solubilization and results in a purer PVK phase. NH4Cl allows the control of the crystallization growth speed, leading to the formation of large crystal grains and well‐crystallized layers. By the glow‐discharge optical emission spectroscopy (GD‐OES) technique, it is directly visualized that potassium incorporated in the whole film blocks the iodide mobility by defect passivation. Also, the reduction (or suppression) of iodide mobility and the reduction (or suppression) of the J–V curve hysteresis is clearly correlated. It is found that blocking the ionic mobility is insufficient to fully stabilize the halide perovskite material which also requires the crystallization monitoring carried out in parallel by the second additive. It resulted in Cs0.1FA0.9PbI3 cells with a stabilized power conversion efficiency (PCE) of 20.02% and with superior stability.
Using Radio‐Frequency Identification Technology to Monitor Eurasian Beavers
Authors: Briggs Alexander J. A. , Robstad Christian A. , Rosell Frank
Published: March 2021

The use of radio‐frequency identification (RFID) offers new potential in remote wildlife monitoring to reduce the invasive nature of studies requiring direct contact with study animals. Facilitated by the emergence of new technology, RFID can remotely identify individual animals implanted with passive‐integrated‐transponder (PIT) tags. We aimed to establish and assess a new technique for remote RFID for remotely and noninvasively monitoring a wild population of a semi‐aquatic mammal, the Eurasian beaver (Castor fiber). A fixed reader was installed from June 2018 to July 2019 at beaver lodges within the territories of 8 family‐groups in Vestfold and Telemark, Norway, for 3 nights per lodge, with RFID antennas at lodge entrances. Microchipped beavers were detected when entering or leaving the lodge. The family‐group size recorded using RFID was compared to the known family‐group size based on live capture records and direct observations. The family‐group size recorded using RFID was smaller than the known family‐group size. However, testing suggested that individuals inhabiting a lodge with a fixed reader installed had a high probability of detection (98.44%). Fixed readers are effective where the identification of individuals at a focal point is appropriate, with unique applications for monitoring species with high fidelity to lodges or dens, or species that exhibit central‐place foraging behavior. Research using RFID through fixed PIT tag readers should be given priority for noninvasive beaver population monitoring. Whereas fixed PIT tag readers may not record entire beaver family‐groups, they provide an accurate and efficient alternative to other monitoring techniques. © 2021 The Authors. Wildlife Society Bulletin published by Wiley Periodicals LLC on behalf of The Wildlife Society.
Purple Martin Nest House Selection in Central Alberta, Canada
Authors: ANDERSON BRITT C. , HVENEGAARD GLEN T.
Published: March 2021

Purple martins (Progne subis) are declining in North America and the eastern subspecies is almost fully dependent on human‐provided nesting houses. We assessed nest house selection by purple martins located at the northern edge of their range. Guidebooks anecdotally describe the importance of house color, building material, hole shape, height, presence of shrubs, vertical accessibility, and distances to trees, water bodies, human houses, and neighboring nest houses; however, these recommendations have little supporting research. Based on data from 2006 to 2018 in Camrose, Alberta, Canada, occupancy was predicted by vertical accessibility, the absence of shrubs at the base of a nest house, location on city‐owned land, and closer proximity to water. Purple martin landlords can build and manage nest houses with certain characteristics to promote greater nesting occupancy by purple martins, thus contributing to more effective purple martin conservation efforts. © 2021 The Wildlife Society.
Large-N SU(N) Yang-Mills theories with milder topological freezing
Authors: Bonanno Claudio , Bonati Claudio , D’Elia Massimo
Published: March 2021

Abstract

We simulate 4d SU(N) pure-gauge theories at large N using a parallel tempering scheme that combines simulations with open and periodic boundary conditions, implementing the algorithm originally proposed by Martin Hasenbusch for 2d CPN–1 models. That allows to dramatically suppress the topological freezing suffered from standard local algorithms, reducing the autocorrelation time of Q2 up to two orders of magnitude. Using this algorithm in combination with simulations at non-zero imaginary θ we are able to refine state-of-the-art results for the large-N behavior of the quartic coefficient of the θ-dependence of the vacuum energy b2, reaching an accuracy comparable with that of the large-N limit of the topological susceptibility.
Implicit Equations Involving the p-Laplace Operator
Authors: Marino Greta , Paratore Andrea
Published: March 2021

In this work we study the existence of solutions$$u \in W^{1,p}_0(\Omega )$$u∈W01,p(Ω)to the implicit elliptic problem$$ f(x, u, \nabla u, \Delta _p u)= 0$$f(x,u,∇u,Δpu)=0in$$ \Omega $$Ω, where$$ \Omega $$Ωis a bounded domain in$$ {\mathbb {R}}^N $$RN,$$ N \ge 2 $$N≥2, with smooth boundary$$ \partial \Omega $$∂Ω,$$ 1< p< \infty $$1<p<∞, and$$ f:\Omega \times {\mathbb {R}}\times {\mathbb {R}}^N \times {\mathbb {R}}\rightarrow {\mathbb {R}}$$f:Ω×R×RN×R→R. We choose the particular case when the functionfcan be expressed in the form$$ f(x, z, w, y)= \varphi (x, z, w)- \psi (y) $$f(x,z,w,y)=φ(x,z,w)-ψ(y), where the function$$ \psi $$ψdepends only on thep-Laplacian$$ \Delta _p u $$Δpu. We also present some applications of our results.
Walks with Small Steps in the 4D-Orthant
Authors: Buchacher Manfred , Hofmanninger Sophie , Kauers Manuel
Published: March 2021

We provide some first experimental data about generating functions of restricted lattice walks with small steps in $${\mathbb {N}}^4$$N4.
Metric Fourier Approximation of Set-Valued Functions of Bounded Variation
Authors: Berdysheva Elena E. , Dyn Nira , Farkhi Elza , Mokhov Alona
Published: March 2021

We introduce and investigate an adaptation of Fourier series to set-valued functions (multifunctions, SVFs) of bounded variation. In our approach we define an analogue of the partial sums of the Fourier series with the help of the Dirichlet kernel using the newly defined weighted metric integral. We derive error bounds for these approximants. As a consequence, we prove that the sequence of the partial sums converges pointwisely in the Hausdorff metric to the values of the approximated set-valued function at its points of continuity, or to a certain set described in terms of the metric selections of the approximated multifunction at a point of discontinuity. Our error bounds are obtained with the help of the new notions of one-sided local moduli and quasi-moduli of continuity which we discuss more generally for functions with values in metric spaces.
Influence of wood pretreatment and fly ash particle size on the performance of geopolymer wood composite
Authors: Asante Bright , Schmidt Goran , Teixeira Ronaldo , Krause Andreas , Savastano Junior Holmer
Published: March 2021

In search for greener building materials, geopolymer wood composites (GWC) were produced through alkali activation of fly ash, using pine and eucalypt wood particles. The study examined the influence of grinding fly ash, wood species and hot water treatment of wood particles on the physical properties and specific compressive strength of GWC before and after 200 cycles of soaking and drying. Ash-grinding affected particle size distribution, as the hot water pretreatment of the wood affected its extractives. The particle size analysis showed that grinding decreased the mean particle size of raw ash by 55% and played a major role in the composite’s properties, as lower densities and specific strength with high water absorption were recorded for GWC from raw ash than from ground ash. The ash-grinding step doubled the specific strength of the composites before the aging test. A decrease in specific strength (15–32%) was observed for all composites after the soaking and drying cycles. Hot water washing of the wood resulted in a 47% and 67% reduction in the extractive content of the pine and eucalypt particles, respectively. An improvement of 27% and 3% was noted in specific strength values respectively for GWC with treated pine and eucalypt particles. In general, lower specific strength was recorded for pine-based composites than eucalypt ones, due to the fast impregnation and high water absorption from the mixture by pine particles. It was revealed that hot water treatment of wood improves GWC properties less compared to wood species or fly ash particle size.
An image processing algorithm for detection and analysis of slicing checks
Authors: Grubîi Victor , Johansson Jimmy
Published: March 2021

In this paper, a new method of measuring slicing checks for flat-sliced veneers was evaluated. The method is based on image analysis of veneer cross-sections, having highlighted the slicing checks using surface staining. The segmentation of the checks consists of global thresholding followed by some morphological operations. The outputs of the algorithm are check depth ratio and check frequency. The method was tested on flat-sliced oak (Quercus robur L. and Quercus petraea (Matt). Liebl.) veneers of different thicknesses (1.5, 2.5, 3.5 and 4.5 mm). Two distinct wood qualities and two different cutting directions (lengthwise-sliced and plain-sliced veneers) were evaluated. The algorithm performance resulted in an overall accuracy of 85% enabling an accessible method for relatively fast and accurate measurements of slicing check characteristics in lamella cross-sections. Regression analysis indicated a lack of fixed bias but the presence of proportional bias with the presented method. Check measurements indicate that by varying cutting parameters, it is possible to achieve desired check characteristics independent of slicing thickness. The semi-automated slicing check detection method could benefit further research and optimisation of the slicing process parameters and pave the way towards industrial quality control of slicing checks. The intended area of application is veneer-laminated products for interior use with the focus on veneered wood flooring.
Anatomical repair and ligament bracing of Schenck III and IV knee joint dislocations leads to acceptable subjective and kinematic outcomes
Authors: Rosteius Thomas , Jettkant Birger , Rausch Valentin , Lotzien Sebastian , Königshausen Matthias , Schildhauer Thomas Armin , Seybold Dominik , Geßmann Jan
Published: March 2021

Purpose

The aim of this study was to analyze the outcomes of anatomical repair and ligament bracing for Schenck III and IV knee dislocation (KD).

Methods

The results of 27 patients (15 and 12 cases of Schenck III and IV KD, respectively) after a mean follow-up of 18.1 ± 12.1 months (range 6–45 months) were retrospectively reviewed. Twenty-two patients suffered high-kinetic-energy accidents, whereas five patients suffered ultralow-velocity (ULV) trauma due to obesity. The outcome measures were the Lysholm score, Hospital for Special Surgery (HSS) knee score, Knee Society Score (KSS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Short Form 36 (SF-36) score. A kinematic 3D gait analysis with five walking trials was performed to compare the patients and healthy controls.

Results

The mean KSS, HSS score, Lysholm score, and KOOS were 77.4 ± 14.4, 84.6 ± 11.2, 81.5 ± 10.4, and 67.3 ± 16.8, respectively. No intra- or postoperative complications occurred. The mean range of motion deficiency compared to the healthy side was 24.4 ± 18.5°. Ten patients had first-degree residual laxity of the anterior cruciate ligament; 12 and 2 patients had first- and second-degree residual laxity of the collateral ligament, respectively. Five patients underwent additional arthroscopic arthrolysis due to arthrofibrosis at an average of 6.2 ± 1.9 months (range 4–9 months) after the initial surgery. The 3D gait analysis showed no major differences in joint stability or movement between the patients and healthy controls. Only the ULV trauma patients had significantly lower outcome scores and showed larger kinematic deviations in joint movement during the gait analysis.

Conclusion

Anatomical repair with ligament bracing is a suitable surgical procedure in the treatment of KD and provides evidence in clinical practice with the benefit of early, definitive repair and preservation of the native ligaments. Patients reach acceptable subjective and objective functional outcomes, including mainly normalized gait patterns during short-term follow-up, with only minor changes in kinematics and spatial–temporal characteristics. Obese patients who suffered ULV trauma showed significantly inferior outcomes with larger deviations in joint kinematics.

Level of evidence

Level III.
Modelling systemic risk using neural network quantile regression
Authors: Keilbar Georg , Wang Weining
Published: March 2021

We propose a novel approach to calibrate the conditional value-at-risk (CoVaR) of financial institutions based on neural network quantile regression. Building on the estimation results, we model systemic risk spillover effects in a network context across banks by considering the marginal effects of the quantile regression procedure. An out-of-sample analysis shows great performance compared to a linear baseline specification, signifying the importance that nonlinearity plays for modelling systemic risk. We then propose three network-based measures from our fitted results. First, we use the Systemic Network Risk Index (SNRI) as a measure for total systemic risk. A comparison to the existing network-based risk measures reveals that our approach offers a new perspective on systemic risk due to the focus on the lower tail and to the allowance for nonlinear effects. We also introduce the Systemic Fragility Index (SFI) and the Systemic Hazard Index (SHI) as firm-specific measures, which allow us to identify systemically relevant firms during the financial crisis.
Performance of overnight on-call radiology residents in interpreting unenhanced abdominopelvic magnetic resonance imaging studies performed for pediatric right lower quadrant abdominal pain
Authors: Sawyer David M. , Mushtaq Raza , Vedantham Srinivasan , Shareef Faryal , Desoky Sara M. , Arif-Tiwari Hina , Gilbertson-Dahdal Dorothy L. , Udayasankar Unni K.
Published: March 2021

Background

Abdominopelvic magnetic resonance imaging (MRI) is increasingly being used to evaluate children with abdominal pain suspected of having acute appendicitis. At our institution, these examinations are preliminarily interpreted by radiology residents, especially when performed after hours.

Objective

To determine the accuracy of preliminary reports rendered by radiology residents in this setting.

Materials and methods

Three hundred seventy-seven pediatric abdominopelvic MRI examinations were included. The preliminary (resident) and final (attending) radiology reports were coded as diagnosing acute appendicitis or no acute appendicitis. The concordance between resident and attending radiologist interpretations was calculated. Additionally, both resident and attending reports were compared to available surgical pathology or clinical follow-up data.

Results

Overall concordance rate for the diagnosis of acute appendicitis was 97.1%. Concordance for verified cases of acute appendicitis was 93.4%. Concordance rates did not differ by residents’ postgraduate year levels. When compared against surgical pathology or clinical follow-up data, residents demonstrated 91.2% sensitivity and 97.6% specificity. There was no statistically significant difference in the sensitivity or specificity of resident or attending radiologist interpretations.

Conclusion

Radiology residents demonstrate high concordance with attending pediatric radiologists in their interpretations of pediatric abdominopelvic MRI for acute appendicitis. The diagnostic performances of residents and attendings were comparable.