bluuebunny/crossref_metadata_2025 huggingface dataset:
Positions of the horizontal and vertical centre of rotation in eyes with different refractive errors
Authors: Ohlendorf Arne , Schaeffel Frank , Wahl Siegfried
Published: January 2022

Purpose

To determine how the position of the centre of rotation of the eyeball is related to axial length and refractive error when horizontal and vertical eye movements are performed.

Methods

A custom‐built eye tracker was used that determined the centre of rotation of the eye (COR) from lateral displacements of the pupil centre. Horizontal and vertical eye movements were studied in the right eyes, and each measurement performed five times in 59 subjects (32 females) with an average age of 36.6 ± 9.1 years. Spherical equivalent refractive errors ranged from −9.7 to +6.8 D with an average error of −1.5 ± 2.9 D. Axial lengths were measured with the ZEISS IOL Master 500.

Results

The mean horizontal centre of rotation (COR) of the right eye for a saccade from 0° to ±11.9° was 15.3 ± 1.5 mm behind the corneal apex, while the average vertical COR for the same angle of eccentricity was 12.5 ± 1.4 mm, indicating that the horizontal COR was 2.8 ± 1.7 mm behind the vertical COR. In right eyes, horizontal COR was significantly correlated with axial length (r = 0.28, p = 0.02) but not with the spherical equivalent refractive error (r = 0.39, p = 0.90). Similarly, vertical COR was significantly correlated with axial length (r = 0.25, p = 0.03) but not with the spherical equivalent refractive error (r = 0.17, p = 0.90).

Conclusions

While it might be expected that the COR is dependent on axial length, the correlation was not strong. Interestingly, the location of the COR was substantially different for horizontal and vertical eye movements which may relate to the flatter curvature of the eyeball in the vertical meridian, compared to the horizontal, as described in previous studies.
China's anti‐corruption campaign and outward foreign direct investment by state‐owned enterprises
Authors: Qi Zhen , Kenderdine Tristan , Tang Tingfeng , Liu Qiren
Published: January 2022

This paper explores political factors in the determination of China's State‐Owned Enterprises' (SOEs') outward foreign direct investment (OFDI). We examine China's anti‐corruption campaign as a political intervention into economic decision making. Based on reliable data on China SOEs' OFDI, we find that the anti‐corruption campaign launched by the Chinese Communist Party in 2013 has had a negative influence on the growth of SOEs' OFDI. Further statistical analysis suggests that the negative impact of the anti‐corruption campaign on SOEs' OFDI growth is greater when the anti‐corruption effort is stronger, the SOE more monopolistic, and the institutional quality of the host state greater.
Reflexiones en torno a la exigencia de la relación de causalidad entre el incumplimiento del deber de declarar el verdadero estado del riesgo y la ulterior materialización del siniestro
Authors: Jaramillo Mor Carlos Esteban
Published: January 2022

El presente escrito tiene como finalidad primordial, tal y como su título permite anticiparlo, realizar un estudio preliminar y, por ende de aproximación, a una de las cuestiones que consideramos que revisten mayor relevancia -tanto práctica como teórica- en la actualidad en materia aseguraticia, particularmente en el ámbito de la regulación del reconocido deber de declarar el verdadero estado del riesgo en la fase precontractual, concretamente al valor que se le puede, o que se le debe dar a la eventual inexistencia de una vinculación o concatenación causal encaminada a enlazar el incumplimiento del precitado deber con la efectiva y la ulterior materialización del riesgo asegurado (siniestro). Ello, para efectos de aplicar o inaplicar los mecanismos correctivos y sancionatorios que los diferentes ordenamientos jurídicos han adoptado como respuesta al incumplimiento de tan aquilatado deber, en especial la nulidad del seguro.

Con dicho propósito, este escrito se orienta al estudio comparativo de la anunciada temática, del que se desprende que en las últimas décadas, a tono con los nuevos derroteros del Derecho de seguros en la contemporaneidad (civil law y common law), gradualmente se ha abierto camino una nueva manera de acercarse a ella en el campo legislativo, con el fin de atribuirle significación, en lo pertinente, a la exigencia de una relación causal siniestral como un requisito para dar cabida a la liberación del asegurador en los eventos en los cuales se hayan comprobado reticencias o inexactitudes, particularmente en aras de exaltar el principio de la conservación de los efectos del contrato, de tanta trascendencia hoy por hoy, previa observancia de específicas limitaciones. 

En este estudio, además, sucintamente se examinarán las razones que en el Derecho comparado se han esgrimido en pro y en contra de dicha exigencia causal, ciertamente polémica y, en tal virtud  no unánime, pues si bien es cierto que se en los últimos tiempos se ha evidenciado un cambio legislativo al respecto en algunas naciones, éste no se puede generalizar, toda vez que se requiere del detenido y cuidadoso examen de cada una de las legislaciones y ordenamientos individuales, de la mano de la jurisprudencia respectiva, en aras de asegurar la coherencia en el campo hermenéutico, y de favorecer la estabilidad, la certidumbre y la seguridad jurídicas. Y con mayor razón, cuando en este tema claramente hay más de una respuesta normativa: negativa, o positiva en relación con la citada exigencia causal siniestral, y más de un matiz o excepción, diversidad de respuestas y de aristas que ameritan ser tenidas muy en cuenta, para no alterar la realidad de cada legislación y de su historia normativa, tal y como justamente tiene lugar en Colombia, en la que hay que diferenciar ‘el ser’, de un eventual ‘deber ser’ legislativo, según el caso.
Two new genera of winterschmidtiine mites (Acari: Astigmata: Winterschmidtiidae) associated with beetles in the family Bostrichidae (Coleoptera: Polyphaga: Bostrichoidea)
Authors: Oconnor Barry M.
Published: January 2022

Deutonymphs of two new genera in the family Winterschmidtiidae, subfamily Winterschmidtiinae, are described from the Eastern United States and compared with existing taxa. Bostrichiella delfinadoae gen. nov., sp. nov. is described from Xylobiops basilaris (Say, 1824) from Connecticut, Tennessee, Louisiana and Florida. Xylacarus bauchani gen. nov., sp. nov. is described from Amphicerus bicaudatus (Say, 1824) and A. cornutus (Pallas, 1772), from New Jersey, New York, Michigan and Florida. A few specimens of each species were collected from other bostrichid species. The two new genera are sister-taxa and more closely related to Winterschmidtia than to Parawinterschmidtia. A table of all species included in the Winterschmidtiinae is presented.
The effects of lambda-cyhalothrin and bifenthrin resistance on the fitness of Tetranychus urticae Koch (Acari: Tetranychidae)
Authors: Susurluk Hilal , Gürkan M. Oktay
Published: January 2022

Lambda-cyhalothrin and bifenthrin from pyrethroids have been used for many years to control the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), which causes serious economic damage in many cultivated and ornamental plants worldwide. In this study, resistant populations previously selected in the laboratory with lambda cyhalothrin and bifenthrin (LR and BR, respectively) were compared with the susceptible strain GSS to assess the effect of the resistance on fitness. Life tables were created by using some biological parameters such as development time, fecundity and adult longevity. Data analysis revealed that lambda-cyhalothrin and bifenthrin resistant populations of T. urticae had no fitness disadvantages. The relative fitness values of the LR (1.09) and BR (1.19) populations also showed an advantage over the susceptible population. Total development and generation time were prolonged in both resistant populations. In the LR population, the life span of the adult females was prolonged, whereas the rm value was found to increase in the BR population. Total fecundity and egg hatchability were also found to be higher in both resistant populations than the susceptible strain GSS. The net reproduction rate (R0), one of the life table parameters, was significantly increased in the LR and BR populations. In this study, lambda-cyhalothrin and bifenthrin resistance affected some biological parameters in T.urticae, but the resistance did not produce a loss of fitness in the LR and BR populations. These findings have significant implications for resistance management strategies in terms of the state and management of resistance.
Studies on Chinese water mites: The genus Feltria Koenike, 1892 (Acari: Feltriidae)
Authors: Li Hai-Tao , Ding Zhu-Hui , Gu Xin-Yao , Guo Jian-Jun
Published: January 2022

This paper further enriches the taxonomic study of Feltriidae Viets, 1926 in China since it was first reported by Yi & Jin in 2011. Seven species, Feltria hanmaensis sp. nov., Feltria pesici sp. nov., Feltria pseudoparva sp. nov., Feltria expendis sp. nov., Feltria yinjiangensis sp. nov., Feltria neoflatheadensis sp. nov. and Feltria glandulosa sp. nov., are described as new to science; Feltria minuta Koenike, 1892 is new to the Chinese water mite fauna. In addition, some slit organs of these species are photographed by SEM (scanning electron microscope) and illustrated in detail by optical microscope to provide material for exploiting valuable character in specific identification.
Sexual selection and the ascent of women: Mate choice research since Darwin
Authors: Rosenthal Gil G. , Ryan Michael J.
Published: January 2022

Darwin’s theory of sexual selection fundamentally changed how we think about sex and evolution. The struggle over mating and fertilization is a powerful driver of diversification within and among species. Contemporaries dismissed Darwin’s conjecture of a “taste for the beautiful” as favoring particular mates over others, but there is now overwhelming evidence for a primary role of both male and female mate choice in sexual selection. Darwin’s misogyny precluded much analysis of the “taste”; an increasing focus on mate choice mechanisms before, during, and after mating reveals that these often evolve in response to selection pressures that have little to do with sexual selection on chosen traits. Where traits and preferences do coevolve, they can do so whether fitness effects on choosers are positive, neutral, or negative. The spectrum of selection on traits and preferences, and how traits and preferences respond to social effects, determine how sexual selection and mate choice influence broader-scale processes like reproductive isolation and population responses to environmental change.
RALF peptide signaling controls the polytubey block in
Arabidopsis
Authors: Zhong Sheng , Li Ling , Wang Zhijuan , Ge Zengxiang , Li Qiyun , Bleckmann Andrea , Wang Jizong , Song Zihan , Shi Yihao , Liu Tianxu , Li Luhan , Zhou Huabin , Wang Yanyan , Zhang Li , Wu Hen-Ming , Lai Luhua , Gu Hongya , Dong Juan , Cheung Alice Y. , Dresselhaus Thomas , Qu Li-Jia
Published: January 2022

Fertilization of an egg by multiple sperm (polyspermy) leads to lethal genome imbalance and chromosome segregation defects. In
Arabidopsis thaliana
, the block to polyspermy is facilitated by a mechanism that prevents polytubey (the arrival of multiple pollen tubes to one ovule). We show here that FERONIA, ANJEA, and HERCULES RECEPTOR KINASE 1 receptor-like kinases located at the septum interact with pollen tube–specific RALF6, 7, 16, 36, and 37 peptide ligands to establish this polytubey block. The same combination of RALF (rapid alkalinization factor) peptides and receptor complexes controls pollen tube reception and rupture inside the targeted ovule. Pollen tube rupture releases the polytubey block at the septum, which allows the emergence of secondary pollen tubes upon fertilization failure. Thus, orchestrated steps in the fertilization process in
Arabidopsis
are coordinated by the same signaling components to guarantee and optimize reproductive success.
A controversial train heads for the Maya forest
Authors: Ortega Rodrigo Pérez , Jaber Inés Gutiérrez
Published: January 2022

Critics fear Mexico’s presidential megaproject could threaten ecology, archaeology
Endoscopic ultrasound in the monitoring of the intestinal allograft
Authors: Oltean Mihai , Hedenström Per , Varkey Jonas , Herlenius Gustaf , Sadik Riadh
Published: January 2022

Objective

Chronic rejection (CR) of the small intestinal allograft includes mucosal fibrosis, bowel thickening and arteriopathy in the outer wall layers and the mesentery. CR lacks non-invasive markers and reliable diagnostic methods. We evaluated endoscopic ultrasound (EUS) as a novel approach for monitoring of the intestinal allograft with respect to CR.

Design

In intestinal graft recipients, EUS and enteroscopy with ileal mucosal biopsy were performed via the ileostomy. At EUS, the wall thickness of the intestinal graft was measured in standard mode, whereas the resistive index (RI) of the supplying artery was assessed in pulsed Doppler mode. At enteroscopy, the intestinal mucosa was assessed. Findings were compared with histopathology and clinical follow-up.

Results

EUS was successfully performed in all 11 patients (adequate clinical course (AC) n=9; CR n=2) after a median interval of 1537 days (range: 170–5204), post-transplantation. The total diameter of the wall (layer I–V) was comparable in all patients. Meanwhile, the diameter of the outermost part (layer IV–V; that is, muscularis propria–serosa) was among the two CR patients (range: 1.3–1.4 mm) in the upper end of measurements as compared with the nine AC patients (range: 0.5–1.4 mm). The RI was >0.9 in both CR patients, while the RI was ≤0.8 in all AC patients. Both CR patients had abnormal findings at enteroscopy and histopathology and deceased during follow-up.

Conclusion

EUS is a promising tool providing detailed information on the intestinal graft morphology and rheology, which may be used for assessment of potential CR in long-term follow-up of intestinal allograft recipients.
Current use of inotropes according to initial blood pressure and peripheral perfusion in the treatment of congestive heart failure: findings from a multicentre observational study
Authors: Nagao Kazuya , Kato Takao , Yaku Hidenori , Morimoto Takeshi , Inuzuka Yasutaka , Tamaki Yodo , Yamamoto Erika , Yoshikawa Yusuke , Kitai Takeshi , Taniguchi Ryoji , Iguchi Moritake , Kato Masashi , Takahashi Mamoru , Jinnai Toshikazu , Ikeda Tomoyuki , Kawai Takafumi , Komasa Akihiro , Nishikawa Ryusuke , Kawase Yuichi , Morinaga Takashi , Su Kanae , Kawato Mitsunori , Seko Yuta , Inada Tsukasa , Inoko Moriaki , Toyofuku Mamoru , Furukawa Yutaka , Nakagawa Yoshihisa , Ando Kenji , Kadota Kazushige , Shizuta Satoshi , Ono Koh , Sato Yukihito , Kuwahara Koichiro , Ozasa Neiko , Kimura Takeshi
Published: January 2022

Objectives

Current guidelines restrict the use of inotropes for the treatment for heart failure (HF) unless the patients are hypotensive or hypoperfused because of safety concerns. This study sought to characterise the contemporary real-world use of inotropes and associated long-term outcomes according to systolic blood pressure (sBP) and perfusion status.

Design

A multicentre prospective cohort study.

Setting

This study was nested from the Kyoto Congestive Heart Failure registry, which included consecutive Japanese patients admitted for HF.

Participants

We categorised 3995 patients into two groups: sBP ≥90 mm Hg and warm profile group, and sBP <90 mm Hg or cold profile group. In each group, patients were stratified across the use of inotropes within 24 hours of hospital presentation.

Primary and secondary outcomes

The primary outcome was all-cause death throughout follow-up. Secondary outcomes included cardiovascular death throughout follow-up, all-cause death during index hospitalisation and after discharge, and HF hospitalisation.

Results

A total of 793 patients (20%) presented with sBP <90 mm Hg or cold profile, whereas 3202 patients had sBP ≥90 mm Hg and warm profile; 276 patients (35%) in the sBP <90 mm Hg/cold group and 312 patients (10%) in the sBP ≥90 mm Hg/warm group received initial inotropic treatment. Adjusted excess risk of inotrope use relative to no inotrope for the primary outcome measure was significant in the sBP ≥90 mm Hg/warm group (adjusted HR), 1.36; 95% CI 1.09 to 1.72, p=0.006) but not in the sBP <90 mm Hg/cold group (adjusted HR, 1.28, 95% CI 0.96 to 1.69, p=0.09). Risk for postdischarge all-cause death and HF hospitalisation was not significantly different between the patients with inotropes and no inotropes in both groups.

Conclusion

Inotrope use in the absence of hypotension and hypoperfusion is still common, but associated with a worse long-term prognosis.

Trial registration number

UMIN000015238.
Abdominal aortic aneurysm clinical practice guidelines: a methodological assessment using the AGREE II instrument
Authors: Tan Kia Hau Matthew , Salim Safa , Machin Matthew , Geroult Aurélien , Onida Sarah , Lane Tristan , Davies A H
Published: January 2022

Objectives

Abdominal aortic aneurysm (AAA) clinical practice guidelines (CPGs) provide evidence-based information on patient management; however, methodological differences exist in the development of CPGs. This study examines the methodological quality of AAA CPGs using a validated assessment tool.

Methods

Medline, EMBASE and online CPG databases were searched from 1946 to 31 October 2021. Full-text, English language, evidence-based AAA CPGs were included. Consensus-based CPGs, summaries of CPGs or CPGs which were only available on purchase were excluded. Five reviewers assessed their quality using the Appraisal of Guidelines for Research and Evaluation II instrument. An overall guideline assessment scaled score of ≥80% was considered as the threshold to recommend CPG use in clinical practice.

Results

Seven CPGs were identified. Scores showed good inter-reviewer reliability (intraclass correlation coefficient 0.943, 95% CI 0.915 to 0.964). On average, CPGs performed adequately with mean scaled scores of over 50% in all domains. However, between CPGs, significant methodological heterogeneity was observed in all domains. Four CPGs scored ≥80% (European Society of Cardiology, the Society of Vascular Surgery, the European Society of Vascular Surgery and the National Institute of Health and Care Excellence), supporting their use in clinical practice.

Conclusions

Four CPGs were considered of adequate methodological quality to recommend their use in clinical practice; nonetheless, these still showed areas for improvement, potentially through performing economic analysis and trial application of recommendations. A structured approach employing validated CPG creation tools should be used to improve rigour of AAA CPGs. Future work should also evaluate recommendation accuracy using validated appraisal tools.
Appetite for more exchange, connection and collaboration among senior health professionals
Authors: Sharp Sara , Prasad Anjana , Sugavanam Anita
Published: January 2022

Background

The COVID-19 pandemic has highlighted the value of global exchange around knowledge, skills and attitudes among senior healthcare professionals (SHPs). It has also revealed the need for strong peer-led networks and mentorship to tackle the high levels of burnout and ‘brain-drain’ already plaguing the National Health Service (NHS). We designed a survey to gauge the appetite for exchange programmes among SHPs.

Methods

Data collection was carried out via an online qualitative survey generated by SurveyMonkey software and analysed by three independent authors.

Results

155 responses were collected of which 87.7% were pre-COVID-19 pandemic. 74.2% had ideas to improve healthcare but could not take it forward. 86.6% felt frustrated/down-heartened about work. 74.3% wanted more sharing of teaching resources. 74.2% expressed interest in sabbatical programmes.

Conclusion

Our survey confirms the desire for more connection, collaboration and exchange among SHPs who are at high risk of burnout, silo-working and leaving the profession early. Sabbaticals have been used successfully in other industries, especially academia, for many years and show long-term investment and value from employers in their employees. Almost 75% of the SHPs in this survey were interested in this but logistics precluded easy access to them. HealthProMatch (HPM) is a platform where SHPs can connect, collaborate and arrange exchanges/sabbaticals with logistical ease. It focuses on bringing leadership, mentorship and quality improvement back home. HPM will pilot in the NHS within anaesthesia and hopes to increase job satisfaction and retention in this precious workforce group.
Influence of the interventionist’s experience on outcomes of endovascular thrombectomy in acute ischemic stroke: results from the MR CLEAN Registry
Authors: Olthuis Susanne G H , den Hartog Sanne J , van Kuijk Sander M J , Staals Julie , Benali Faysal , van der Leij Christiaan , Beumer Debbie , Lycklama à Nijeholt Geert J , Uyttenboogaart Maarten , Martens Jasper M , van Doormaal Pieter-Jan , Vos Jan Albert , Emmer Bart J , Dippel Diederik W J , van Zwam Wim H , van Oostenbrugge Robert J , de Ridder Inger R
Published: January 2022

Background

The relationship between the interventionist’s experience and outcomes of endovascular thrombectomy (EVT) for acute ischemic stroke of the anterior circulation, is unclear.

Objective

To assess the effect of the interventionist’s level of experience on clinical, imaging, and workflow outcomes. Secondly, to determine which of the three experience definitions is most strongly associated with these outcome measures.

Methods

We analysed data from 2700 patients, included in the MR CLEAN Registry. We defined interventionist’s experience as the number of procedures performed in the year preceding the intervention (EXPfreq), total number of procedures performed (EXPno), and years of experience (EXPyears). Our outcomes were the baseline-adjusted National Institutes of Health Stroke Scale (NIHSS) score at 24–48 hours post-EVT, recanalization (extended Thrombolysis in Cerebral Infarction (eTICI) score ≥2B), and procedural duration. We used multilevel regression models with interventionists as random intercept. For EXPfreq and EXPno results were expressed per 10 procedures.

Results

Increased EXPfreq was associated with lower 24–48 hour NIHSS scores (adjusted (a)β:−0.46, 95% CI −0.70 to −0.21). EXPno and EXPyears were not associated with short-term neurological outcomes. Increased EXPfreq and EXPno were both associated with recanalization (aOR=1.20, 95% CI 1.11 to 1.31 and aOR=1.08, 95% CI 1.04 to 1.12, respectively), and increased EXPfreq, EXPno, and EXPyears were all associated with shorter procedure times (aβ:−3.08, 95% CI−4.32 to −1.84; aβ:−1.34, 95% CI−1.84 to −0.85; and aβ:−0.79, 95% CI−1.45 to −0.13, respectively).

Conclusions

Higher levels of interventionist’s experience are associated with better outcomes after EVT, in particular when experience is defined as the number of patients treated in the preceding year. Every 20 procedures more per year is associated with approximately one NIHSS score point decrease, an increased probability for recanalization (aOR=1.44), and a 6-minute shorter procedure time.
Prospective arrhythmia surveillance after a COVID-19 diagnosis
Authors: Dewland Thomas A , Whitman Isaac R , Win Sithu , Sanchez Jose M , Olgin Jeffrey E , Pletcher Mark J , Santhosh Lekshmi , Kumar Uday , Joyce Sean , Yang Vivian , Hwang Janet , Ogomori Kelsey , Peyser Noah , Horner Cathy , Wen David , Butcher Xochitl , Marcus Gregory M
Published: January 2022

Background

Cardiac arrhythmias have been observed among patients hospitalised with acute COVID-19 infection, and palpitations remain a common symptom among the much larger outpatient population of COVID-19 survivors in the convalescent stage of the disease.

Objective

To determine arrhythmia prevalence among outpatients after a COVID-19 diagnosis.

Methods

Adults with a positive COVID-19 test and without a history of arrhythmia were prospectively evaluated with 14-day ambulatory electrocardiographic monitoring. Participants were instructed to trigger the monitor for palpitations.

Results

A total of 51 individuals (mean age 42±11 years, 65% women) underwent monitoring at a median 75 (IQR 34–126) days after a positive COVID-19 test. Median monitoring duration was 13.2 (IQR 10.5–13.8) days. No participant demonstrated atrial fibrillation, atrial flutter, sustained supraventricular tachycardia (SVT), sustained ventricular tachycardia or infranodal atrioventricular block. Nearly all participants (96%) had an ectopic burden of <1%; one participant had a 2.8% supraventricular ectopic burden and one had a 15.4% ventricular ectopic burden. While 47 (92%) participants triggered their monitor for palpitation symptoms, 78% of these triggers were for either sinus rhythm or sinus tachycardia.

Conclusions

We did not find evidence of malignant or sustained arrhythmias in outpatients after a positive COVID-19 diagnosis. While palpitations were common, symptoms frequently corresponded to sinus rhythm/sinus tachycardia or non-malignant arrhythmias such as isolated ectopy or non-sustained SVT. While these findings cannot exclude the possibility of serious arrhythmias in select individuals, they do not support a strong or widespread proarrhythmic effect of COVID-19 infection after resolution of acute illness.
Handwritten New Tai Lue Character Recognition Using Convolutional Prior Features and Deep Variationally Sparse Gaussian Process Modeling
Authors: Guo H. , Dong N. , Zhao J. Y. , Liu Y. F.
Published: January 2022

New Tai Lue is widely used in Southwest China and Southeast Asia. Hence, it is important to study related handwritten character recognition. Considering the many similar characters in handwritten New Tai Lue, this paper proposes an offline handwritten New Tai Lue character recognition method based on convolutional prior features and deep variationally sparse Gaussian process (DVSGP) modeling. An offline handwritten database is constructed, a convolutional neural network is trained to extract the convolutional features of New Tai Lue character images as prior features, and a DVSGP model is built. The extracted features are input into the DVSGP model to construct a recognition model. The experimental results show that the accuracy of the model is 97.67% and that the precision, recall, and F1-score are 0.9769, 0.9767, and 0.9767, respectively, which are better than those of other methods. The proposed method also achieves high accuracy on the MNIST recognition task, verifying its universal applicability.
Combining a Novel Scoring Approach with Arabic Stemming Techniques for Arabic Chatbots Conversation Engine
Authors: Alshammari Nasser O. , Alharbi Fawaz D.
Published: January 2022

Arabic is recognized as one of the main languages around the world. Many attempts and efforts have been done to provide computing solutions to support the language. Developing Arabic chatbots is still an evolving research field and requires extra efforts due to the nature of the language. One of the common tasks of any natural language processing application is the stemming step. It is important for developing chatbots, since it helps with pre-processing the input data and it can be involved with different phases of the chatbot development process. The aim of this article is to combine a scoring approach with Arabic stemming techniques for developing an Arabic chatbot conversation engine. Two experiments are conducted to evaluate the proposed solution. The first experiment is to select which stemmer is more accurate when applying our solution, since our algorithm can support various stemmers. The second experiment was conducted to evaluate our proposed approach against various machine learning models. The results show that the ISRIS stemming algorithm is the best fit for our solution with accuracy 78.06%. The results also indicate that our novel solution achieved an F1 score of 65.5%, while the other machine learning models achieved slightly lower scores. Our study presents a novel technique by combining scoring mechanisms with stemming processes to produce the best answer for every query sent by chatbots users compared to other approaches. This can be helpful for developing Arabic chatbot and can support many domains such as education, business, and health. This technique is among the first techniques that developed purposefully to serve the development of Arabic chatbots conversation engine.
Tailored 3D Foams Decorated with Nanostructured Manganese Oxide for Asymmetric Electrochemical Capacitors
Authors: Siwek K. I. , Eugénio S. , Aldama I. , Rojo J. M. , Amarilla J. M. , Ribeiro A. P. C. , Silva T. M. , Montemor M. F.
Published: January 2022

Tailored 3D (Ni and NiCo) metallic foam architectures were produced by electrodeposition and decorated via electrochemical routes with manganese oxide (MnOx) to serve as positive electrodes for supercapacitors. For comparative purposes, an electrode made of commercial Ni foam was also prepared. The foam-based electrodes were paired with a carbon cloth electrode and used to assemble asymmetric electrochemical cells. The electrochemical response of these cells was studied by applying different electrochemical techniques. In addition, two different protocols (cycling and floating) were applied to assess cells durability and fade. Despite the significant differences in the decorated foams morphology and structure their electrochemical responses revealed similar trends. The electrodes made of tailored foams showed higher specific capacitance, better capacitance retention at high current load and enhanced cycling stability compared to the electrodes made of commercial foam. The asymmetric cells made with the tailored foams revealed higher (maximum) specific energy (11–14 Wh kg−1) and specific power (1.3–1.4 × 104 W kg−1) compared to cells assembled with commercial foams (8.4 Wh kg−1 and 6.3 × 103 W kg−1). The durability tests evidenced that corrosion of the NiCo electrodeposited foams and electrochemical dissolution of MnOx are possible causes of cells degradation.
High Areal Capacitance of Flexible Supercapacitors Fabricated with Carbon Cloth-Carbon Fiber-TiO2 Electrodes and Different Hydrogel Polymer Electrolytes
Authors: Lal Mamta Sham , Ramaprabhu Sundara
Published: January 2022

Developing suitable electrode material and electrolyte is critical for fabricating a flexible supercapacitor with large areal capacitance. Furthermore, the compatibility between electrode material and electrolyte is essential. Herein, a carbon cloth-carbon fiber-TiO2 (CC–CF–TiO2) based flexible electrode is designed and developed for the first time and tested electrochemically in various electrolytes. More importantly, the electrochemical studies performed in both half-cell and full-cell studies are discussed. The highest areal capacitance of 270 mF cm−2 is realized for CC–CF–TiO2 flexible electrode in 1 M H2SO4 aqueous electrolyte at 10 mA cm−2 current density. Full-cell flexible supercapacitor fabricated with hydrogel polymer electrolyte demonstrates the maximum energy density and power density as 4.56 μWh cm−2 and 418.48 μW cm−2 respectively. The attained values are highly encouraging in comparison to the old reports. The results obtained in this work demonstrate the potential of our fabricated flexible supercapacitor for next-generation wearable energy storage applications.
Plasma-Assisted Molecular Beam Epitaxy of In-Rich InGaN: Growth Optimization for Near-IR Lasing
Authors: Kudryavtsev K. E. , Lobanov D. N. , Krasilnikova L. V. , Yablonskiy A. N. , Yunin P. A. , Skorokhodov E.V. , Kalinnikov M. A. , Novikov A.V. , Andreev B. A. , Krasilnik Z. F.
Published: January 2022

Near-infrared stimulated emission (SE) from InGaN layers grown by plasma-assisted molecular beam epitaxy has been studied, and the influence of the growth temperature (T
gr) on the SE threshold has been revealed. The obtained experimental data strongly suggest a two-layer model for the grown InGaN structure with a thin defect-rich interface layer and a relatively pure InGaN bulk responsible for light emission. For the latter, the crystalline quality appears to be unaffected by the growth temperature, at least in terms of free electron concentration, which is supported by the similar spontaneous luminescence intensities measured throughout the entire T
gr range of 430 °C–510 °C. However, the quality of the interface layer improves with increasing T
gr, leading to a decrease in the SE threshold down to ∼10 kW cm−2 at T = 77 K for the samples grown at T
gr = 470 °C–480 °C. For the higher growth temperatures (T
gr ≥ 490 °C), the SE threshold increases rapidly with T
gr, apparently related to the strong waveguide losses due to the increasing surface roughness of the InGaN layer, and SE vanishes completely at T
gr = 510 °C, further suppressed by the partial phase separation of the InGaN alloy.
Inverted Planar Perovskite Solar Cells with High Electrical Conductivity and Efficiency by KBr-Doped PEDOT:PSS
Authors: Wu Yuhan , Duan Guofan
Published: January 2022

The photovoltaic performance of inverted perovskite solar cells (PSCs) is highly determined by the conductivity and charge transfer efficiency of the hole transport layer (HTL). In order to further strengthen the overall role of HTL, herein, Potassium bromide (KBr) is utilized into poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to improve its own conductivity and interfacial charge transfer. The champion power conversion efficiency (PCE) of the PSCs based on KBr doped HTL is 18.43% with negligible hysteresis, which is higher than the control device with 15.82%. In all photovoltaic parameters, the higher open-circuit voltage and the significantly improved fill factor are particularly prominent. The dual effect of KBr is involved. KBr not only tune the electronic property of PEDOT:PSS, but also makes it have better hole mobility. Beside the changes in HTL, the perovskite film shows a favorable crystal orientation for hole transport on modified HTL, resulting in a compact and smooth film. In this work, KBr is added to PEDOT:PSS with inverted perovskite devices, which provides a simple and efficient method for the commercialization of high-efficiency PSCs.
A new framework for analysis of three-dimensional shape and architecture of human skeletal muscles from in vivo imaging data
Authors: Bolsterlee Bart
Published: January 2022

Muscle architecture is conventionally measured using simple scalar metrics such as muscle volume and average fascicle lengths. Here, a new framework is proposed for analysis of complex changes in three-dimensional architecture of whole human muscles from magnetic resonance and diffusion tensor imaging data. The general use of the framework is demonstrated through visualization, quantification, and statistical analysis of the effect of strength training, passive lengthening and cerebral palsy on three-dimensional muscle shape and architecture.
Six weeks of static apnea training does not affect Hbmass and exercise performance
Authors: Bouten Janne , Debusschere Jonas , Lootens Leen , Declercq Louise , Van Eenoo Peter , Boone Jan , Bourgois Jan G.
Published: January 2022

Apnea training has been suggested as a promising method to improve exercise performance for over a decade. However, to our knowledge, this study is the first to evaluate its value on both hematological parameters and exercise performance, including Hbmass and a control group. No changes in Hbmass nor exercise performance were observed. Contradicting previous research, no acute increase in [EPO] following apnea was observed either, indicating that more intense protocols are needed, at least in nonapnea-trained individuals.
Magnetohydrodynamic Thin Film Flow through a Porous Stretching Sheet with the Impact of Thermal Radiation and Viscous Dissipation
Authors: Khan Ziad , Jawad Muhammad , Bonyah Ebenezer , Khan Naveed , Jan Rashid
Published: January 2022

In this paper, the Darcy–Forchheimer laminar thin film flow with MHD and heat transfer on an unsteady horizontal stretched surface is investigated. The impact of thermal radiation and viscous dissipation is also considered for thin film flow. The analysis of heat source with thermal radiation in a boundary layer flow can play a great role in manufacturing engineering procedures such as the production of electric power, solar energy modernization, and astrophysical flow. By using similarity transformation, the system of PDEs is converted to ODEs. Then HAM is applied for the solution of the problem. Moreover, the velocity and temperature profile for various embedded variables are discussed through graphs while the numerical solution of concerned physical quantities such as skin friction and Nusselt number are discussed through tables. The analysis shows that velocity profile is reducing function of

M

,

K

1

,

S

, and

F

1

. The temperature profile is an increasing function

S

and

E
c

while a reducing function of

Pr

and

R

. The overall behavior of the proposed system is highlighted analytically.
Experimental Study on Vertical Propagation Behavior of Hydraulic Fracture Affected by Artificial Interlayer for Thick Oil Reservoirs
Authors: Chen Beibei , Qin Yingmin , Xu Peng , Zheng Weijie , Zhang Min , Peng Yan
Published: January 2022

Crude oil distribution in thick oil reservoirs is vertically heterogeneous; therefore, there is usually a dominant sublayer where oil resources are higher than that in other sublayers. The region of hydraulic fracture away from the dominant sublayer plays a negative role in production. In order to enhance efficiency of hydraulic fracturing, the hydraulic fracture height should be restricted around the dominant sublayer and the artificial interlayer is believed as an effective method. However, the propagation mechanism of fracture affected by artificial interlayer has been rarely investigated, which restricts the advance of optimization of artificial interlayer. In this paper, the impact of artificial interlayer on vertical propagation of hydraulic fracture is analyzed by hydraulic fracturing experiments and then the mechanism of artificial interlayer affecting propagation of hydraulic fracture is discussed. Based on the understanding of experimental observations and theory of fracture mechanics, the theoretical model of stress intensity factor for the fracture affected by artificial interlayer is proposed. The experimental data shows that the artificial interlayer can significantly decrease the hydraulic fracture height and the corresponding decrease magnitude of hydraulic fracture height depends on the thickness of artificial interlayer, proppant size, and fracture fluid pumping rate. The dominant mechanism of artificial interlayer restricting hydraulic fracture height is that the drop of fluid pressure induced by the artificial interlayer decreases the stress intensity factor at fracture tip. Based on the theory of fracture mechanics, the stress intensity factor at fracture tip is built and it can consider key factors shown by experimental observations. The fracture height solution from this model is consistent with experimental data, so this model can be used to optimize properties of artificial interlayer.
The Effect of Blast-Hole Arrangement, Delay Time, and Decoupling Charge on Rock Damage and Vibration Attenuation in Multihole Blasting
Authors: Yue H.Z. , Yu C. , Li H.B. , Zhou C.B. , Chen S.H. , Shao Z.S.
Published: January 2022

Rock damage and vibration attenuation are the basis of blasting design, which will affect rock breaking results and the safety of structures (buildings). In this paper, the effect of blast-hole arrangement, delay time, and decoupling charge on the rock damage and the vibration attenuation in multihole blasting were numerically investigated. Through dynamic analysis software ANSYS/LS-DYNA, the JOHNSON_HOLMQUIST_CONCRETE (JHC) rock model and fluid-solid coupling method were used to establish single-hole and multihole rock blasting models. Based on the analysis of single-hole rock damage and vibration, firstly, the effect of the above three factors on the rock damage characteristics of multihole blasting was analyzed. Then, the extracted peak particle velocity (PPV) data of multihole blasting were fitted to the United States Bureau of Mines (USBM) equation to obtain the blasting vibration attenuation parameters (the site constant K and α). It is found that the blast-hole arrangement, delay time, and decoupling charge have a much smaller effect on α than K. At the same time, a delay-time-dependent model of PPV correction coefficient was proposed, and its rationality was verified by field data. The results obtained in this paper have reference significance for optimizing the blasting design and improving the blasting effect.
Patients’ Experience on Practice and Applicability of Informed Consent in Traditional Medical Practice in KwaZulu-Natal Province, South Africa
Authors: Akpa-Inyang Francis , Ojewole Elizabeth , Chima Sylvester C.
Published: January 2022

Background. Informed consent (IC) is constitutionally protected in South Africa based on individual rights to bodily integrity and well-being. In terms of the law, patients cannot be involved in medical treatment or research without IC. This study explored patients’ experience on practice and applicability of IC in African traditional medicine (ATM) in Msunduzi and eThekwini municipalities, KwaZulu-Natal province, South Africa, to evaluate whether important elements of IC such as full information disclosure, capacity, understanding, and volition are considered or being applied during ATM. Methods. This cross-sectional quantitative study was conducted using semistructured questionnaires administered to patients attending traditional health practitioners’ (THPs’) treatment centres. Stata V15.1 was used to analyse variables including descriptive and inferential data analysis. Results. One hundred and twenty-nine (129) participants completed this study, of which 62% were females. Most participants were in the age range of 26–35 (38.8%). All respondents were IsiZulu home-language speakers, single (62.8%), employed (48%), and with some tertiary education (48.8%). Most patients were informed about their diagnosis (58.9%), treatment benefits (79.8%), and recommended treatment (79.8%). Fewer were informed about risks of treatment (36.4%), right of refusal (3.1%), and risks of refusing recommended treatment (0.8%). All participants reported satisfaction with information disclosed by the THPs and did not feel coerced to accept treatment. Consent was obtained verbally in all cases. The majority of participants (76.7%) sought surrogate assistance when consulting THPS, and 81.4% preferred being informed about all treatment risks. Most respondents also preferred involvement in healthcare decision-making during ATM. Conclusion. This study reveals that most patients consulting THPs in the KwaZulu-Natal province for treatment are aware of their right to information disclosure and the need to reach agreement before involvement in ATM treatment procedures. The study also showed that some key elements of IC are currently being applied during ATM practice in South Africa.
On Damage Identification in Planar Frames of Arbitrary Size
Authors: Fiore I. , Greco A. , Pluchino A.
Published: January 2022

Framed structures are deeply studied in civil engineering since they provide a numerical model for the analysis of the static and dynamic response of multi-storey buildings. In order to evaluate the vibrational properties of these structures, an eigen-problem, which involves the stiffness and mass matrices of the frame, must be solved. Both matrices can be assembled by means of standard methods, which take into account the numbers of degrees of freedom of the frame. The occurrence of concentrated damage in some vulnerable sections modifies the degrees of freedom and therefore both the stiffness and mass matrices. Very often, the critical sections are located in the joints between the structural elements of the frame where the bending moment reaches its maximum value. Assuming that the joints are rigid in the undamaged configuration of the frame, it is possible to take into account their loss of stiffness due to the presence of eventual damage by means of hinges with rotational springs of variable rigidity. In this paper, an original algorithm that allows us to evaluate the stiffness and mass matrices and therefore the natural frequencies of vibration of undamaged and damaged planar frames with an arbitrary number of beams and columns is presented. The proposed algorithm for the stiffness and mass matrices determination requires a few input data which can be provided in a text file and therefore allows us to speed up the procedure with respect to the application of an FEM approach which requires the construction of single models for each considered frame. The results obtained by means of the proposed algorithm have been validated through a comparison with those provided by an FEM model implemented in SAP2000. The natural frequencies obtained by means of the proposed approach are used for the solution of two different inverse problems, which concern the identification of, respectively, the mechanical characteristics of the constitutive material and the location and intensity of the damage. Both the proposed identification procedures deal with optimization algorithms that are based on opportune fitness functions. Applications to frames of different size confirm the validity of the presented identification algorithms. Furthermore, an iterative procedure, able to reduce the required computational burden related to the identification of the location and intensity of damage, is presented and applied in a parametric study concerning frames with increasing size.
Automatic Assessment Method of Oral English Based on Multimodality
Authors: Chen Xiaoyan
Published: January 2022

With the rapid development of Internet technology and educational informatization, there are more and more oral materials available on the Internet. Therefore, how to adapt to learners’ dynamic abilities and provide them with personalized learning materials has become a very important issue in educational technology. Aiming at the inefficiency of the existing automatic assessment of spoken English, a multimodal-based automatic assessment method of spoken English is proposed. The Word2Vec model is used to extract text features, and then, speech and text are input into GRU temporal structure, and encoder coding is used for multimodal fusion to realize automatic evaluation of multimodal spoken English. Simulation results show that the multimodal model proposed in this paper is superior to the traditional oral English automatic assessment model in terms of fluency, emotional expression, and sense of rhythm and can better improve learners’ oral English level.