bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding the impact of academic difficulties among medical students: A scoping review
Authors: Kirtchuk David , Wells Geoffrey , Levett Tom , Castledine Clare , de Visser Richard
Published: August 2021

Background

Many medical students may encounter a range of academic and personal challenges during their course of study, but very little is known about their experiences. Our aim was to review the literature to inform future scholarship and to inform policy change.

Methods

A scoping review was conducted searching PubMed, MEDLINE, EMBASE, PsycInfo, British Education Index, Web of Science and ERIC for English language primary research with no date limits. This retrieved 822 papers of which eight met the requirements for inclusion in the review. Data were independently reviewed by two researchers and underwent thematic analysis by the research team.

Results

Three major themes emerged. Theme 1: ‘Identity preservation’ addressed students' aim to preserve their sense of self in the face of academic difficulty and their tendency to seek support. This connected the apprehension many students expressed about their educational institutions to Theme 2: ‘The dual role of the medical school’—medical schools are required to support struggling students but are predominantly seen as a punitive structure acting as the gatekeeper to a successful career in medicine. Students' apprehension and attempts to protect their identities within this complex landscape often resulted in ‘maladaptive coping strategies’ (Theme 3).

Conclusion

Understanding and exploring the academic challenges faced by medical students through their own experiences highlight the need for the development of more individualised remediation strategies. Educators may need to do more to bridge the gap between students and institutions. There is a need to build trust and to work with students to enhance their sense of self and remediate approaches to engagement with learning, rather than focusing efforts on success in assessments and progression.
Serrate‐Associated Protein 1, a splicing‐related protein, promotes miRNA biogenesis in Arabidopsis
Authors: Li Mu , Yu Huihui , Liu Kan , Yang Weilong , Zhou Bangjun , Gan Lu , Li Shengjun , Zhang Chi , Yu Bin
Published: August 2021

MicroRNAs (miRNAs) are essential regulators of gene expression in metazoans and plants. In plants, most miRNAs are generated from primary miRNA transcripts (pri‐miRNAs), which are processed by the Dicer‐like 1 (DCL1) complex along with accessory proteins.

Serrate‐Associated Protein 1 (SEAP1), a conserved splicing‐related protein, has been studied in human and yeast. However, the functions of SEAP1 in plants remain elusive.

Lack of SEAP1 results in embryo lethality and knockdown of SEAP1 by an artificial miRNA (amiRSEAP1) causes pleiotropic developmental defects and reduction in miRNA accumulation. SEAP1 associates with the DCL1 complex, and may promote the interaction of the DCL1 complexes with pri‐miRNAs. SEAP1 also enhances pri‐miRNA accumulation, but does not affect pri‐miRNA transcription, suggesting it may indirectly or directly stabilize pri‐miRNAs. In addition, SEAP1 affects the splicing of some pri‐miRNAs and intron retention of messenger RNAs at global levels.

Our findings uncover both conserved and novel functions of SEAP1 in plants. Besides the role as a splicing factor, SEPA1 may promote miRNA biogenesis by positively modulating pri‐miRNA splicing, processing and/or stability.
Can a complex ecosystem survive the loss of a large fraction of its species? A random matrix theory of secondary extinction
Authors: Emary Clive , Evans Darren
Published: August 2021

Recent estimates suggest that a quarter of species globally are under threat of extinction. Understanding what happens to ecological networks of interacting organisms when they lose a significant fraction of species is thus essential for assessing, and potentially mediating, the current biodiversity crisis. We introduce and explore a framework for studying the repercussions of mass extinctions in large model ecosystems. This random‐matrix approach reveals the statistical properties of the post‐extinction abundances to exhibit a simple structure, allowing us to determine analytically how susceptibility to secondary extinctions depends on the strength and nature of interspecies interaction. We find, for example, that mutualistic networks are particularly sensitive to species loss and that, for small primary extinctions, realistic food webs suffer fewer secondary extinctions than do random ones. Finally we show how the response to low‐level extinctions can be used to predict the effects of more severe events.
Heterodimer formed by ROC8 and ROC5 modulates leaf rolling in rice
Authors: Xu Yang , Kong Weiyi , Wang Fangquan , Wang Jun , Tao Yajun , Li Wenqi , Chen Zhihui , Fan Fangjun , Jiang Yanjie , Zhu Qian‐Hao , Yang Jie
Published: August 2021

Moderately rolled leaf is one of the target traits of the ideal plant architecture in rice breeding. Many genes, including homeodomain leucine zipper IV transcription factors ROC5 and ROC8, regulating rice leaf rolling have been cloned and functionally analysed. However, the molecular mechanism by which these genes modulate leaf‐rolling remains largely elusive. In this study, we demonstrated the transcription activation activity of both ROC8 and ROC5. Overexpressing ROC8 caused adaxially rolled leaves due to decreased number and size of bulliform cells, whereas knockout of ROC8 induced abaxially rolled leaves due to increased number and size of bulliform cells. ROC8 and ROC5 each could form homodimer, but ROC8 interacted preferably with ROC5 to forms a heterodimer. Importantly, we showed that the ROC8‐ROC5 heterodimer rather than the homodimer of ROC8 or ROC5 was functional as neither overexpressing ROC8 in the ROC5 mutant nor overexpressing ROC5 in the ROC8‐knockout line could rescue the mutant phenotype. This was further partially supported by the identification of a large number of common differentially expressed genes in single and double mutants of roc8 and roc5. ROC8 and ROC5 were functionally additive as the phenotype of abaxially rolled leaves was stronger in the roc5roc8 double mutant than in their single mutants. Our results provide evidence for the role of dimerization of ROC members in regulating leaf rolling of rice.
Virtual group visits to reduce psychosocial distress and racial disparities in pediatric vitiligo and alopecia areata patients
Authors: Khosla Natalia N. , Grullon Karina , Rosenblatt Adena E.
Published: August 2021

We examined the potential for virtual, pediatric group visits to reduce racial disparities in psychosocial isolation and access to care among children of color with pediatric vitiligo and alopecia areata as well as their caregivers. We have conducted 10 visits with 30 pediatric skin of color patients between 5 and 16 years old: 18 patients with alopecia areata, 12 with vitiligo, 59% female, 64% Black, and 23% Latinx, and 33 parents. After the visits, children and parents felt they had more people they knew and could reach out to about their dermatologic condition, the visits exceeded both children’s and parents’ expectations, and both children and parents reported that they would continue attending future group visits if offered. Group visits in the virtual format may present an opportunity for reducing racial disparities in psychosocial isolation and access to care across geographic locations in pediatric dermatology.
Domino transplantation for pediatric liver recipients: Obstacles, challenges, and successes
Authors: Raghu Vikram K. , Carr‐Boyd Peter D. , Squires James E. , Vockley Jerry , Goldaracena Nicolas , Mazariegos George V.
Published: August 2021

Background

Domino liver transplantation aims to address the need to increase the liver donor supply. In a domino liver transplant, the domino recipient receives the explanted liver from the recipient of a traditional liver transplant. The domino donor typically requires liver transplant to correct a metabolic disorder; the explanted liver thus has a single gene defect but otherwise normal structure and function.

Methods

In this review, we detail the history of domino liver transplantation, appropriate domino donor indications, the technical advances to the surgical approach, current outcomes, and future opportunities.

Results

Development of de novo disease in the domino recipient has relegated adult domino liver transplant to be considered a source of marginal donor livers. However, pediatric domino liver transplant has leveraged certain metabolic disorders, especially maple syrup urine disease, in which the liver enzyme deficiency can be compensated by the systemic presence of sufficient enzyme. Advances in the surgical aspects of assuring adequate length of vasculature have improved the safety of the procedure in both domino donors and recipients.

Conclusions

Pediatric domino liver transplant utilizing domino donors with specific metabolic liver diseases should be considered a viable live donor option for children awaiting liver transplant.
Discovery of a hidden Triassic Arc in the Southern South China Sea: Evidence for the breakaway of a ribbon continent with implications for the evolution of the Western Pacific margin
Authors: Wei Wu , Liu Chuan‐Zhou , Hou Yi‐Fei , Deng Cheng‐Long , Yan Wen , Li Xian‐Hua , Chung Sun‐Lin , Mitchell Ross N.
Published: August 2021

Paleo‐Pacific subduction generated a prolonged active continental margin along the coast of the South China Block (SCB). A Triassic magmatic gap was argued to have occurred and was ascribed to flat‐slab subduction of an oceanic plateau. We study for the first time a >330‐m‐long core of typical arc volcanics dated at ca. 218 Ma from the Meiji Atoll in the southern South China Sea (SCS). Paleomagnetism suggests 4.1°± 1.5° of post‐eruption southward drift. These observations clearly support the existence of a Triassic arc in the SCB and imply that part of the arc later split off and drifted southward during the opening of the SCS in the Oligocene. Our results better constrain the lateral extent of the proposed flat‐slab subduction along the margin of the SCB. Moreover, we provide direct evidence of how the breakaway of ribbon continents operated in active continental margins, a recurrent scenario that has been invoked for Phanerozoic tectonics and continental growth throughout Asia.
Exploring eating behavior and psychological mechanisms associated with obesity in patients with craniopharyngioma: a scoping review protocol
Authors: Hinton Elanor C. , Elsworth Rebecca L. , Naeem Nimra , Szymkowiak Sophie B. , Perry Rachel , Candler Toby P. , Crowne Elizabeth C. , Gatta-Cherifi Blandine
Published: August 2021

Objective:

The objective of the review is to explore the evidence on the behavioral and psychological mechanisms underlying the development of obesity in patients with craniopharyngioma. The review will map the available evidence, identify gaps in the literature, and find avenues of future intervention.

Introduction:

Craniopharyngiomas are low-grade intracranial tumors of the supersellar region. Obesity is associated with the tumor or surgery or radiotherapy to treat the tumor; however, the behavioral and psychological processes contributing to that association are not clear. This review will provide a synthesized evidence base of the relevant research.

Inclusion criteria:

This review will consider published studies with all types of study designs, including patients with childhood- or adult-onset craniopharyngioma. Articles assessing factors that may impact eating behavior will be included based on the following categories: eating behavior, obesity, neuroimaging, endocrine response, energy expenditure, sleep, and neuropsychology.

Methods:

MEDLINE, Embase, and PsycINFO will be searched, in addition to the Cochrane Library, Web of Science, Scopus, ClinicalTrials.gov, NICE evidence search, and International Standard Randomised Controlled Trial Number (ISRCTN). No limits will be placed on the scope of the search. The methodology will follow a three-stage process with two independent reviewers at each stage, including an initial database search, screening of titles and abstracts of retrieved studies, full-text assessment for inclusion criteria, and hand-searching of reference lists. Data will be extracted using a standardized charting form and summarized in tables. The data will be synthesized using a narrative summary and diagrammatic map and will be based on the evidence for each of the proposed research categories.
Rating scales for medication adherence in people living with Parkinson's disease: a systematic review protocol
Authors: Tosin Michelle Hyczy S. , de Oliveira Beatriz Guitton R.B. , Goetz Christopher G. , Morisky Donald , McConvey Victor , Stebbins Glenn T.
Published: August 2021

Objective:

The objective of the review is to evaluate the measurement properties of rating scales that have been used to assess the components of medication adherence in patients with Parkinson's disease.

Introduction:

Drug therapy is a central strategy in the control of Parkinson's disease symptoms. Measuring behaviors related to medication adherence in patients with Parkinson's disease is vital to understanding the therapeutic response. Consequently, it is necessary to define which instrument offers the most reliable and valid screening.

Inclusion criteria:

This review will consider studies in English and Portuguese using structured rating scales to assess medication adherence in people with Parkinson's disease. Studies including data from patients with different diseases in addition to Parkinson's disease will be included only if data are clearly available for each disorder covered. Study protocols, letters to the editors, reviews, and studies with clinical judgment scales but no operationally defined anchor points will be excluded.

Methods:

A three-step search strategy will be utilized. Databases will include MEDLINE (PubMed), LILACS (BVS Portal), PsycINFO (APA PsycNet), CINAHL (EBSCO), Web of Science (Clarivate Analytics), Embase, and Scopus (Elsevier). The search strategy will be presented using a PRISMA flow diagram. Eligible studies will be critically appraised for methodological quality using the COSMIN Risk of Bias checklist. Criteria for good measurement properties of the selected scales will be summarized narratively using COSMIN, the Movement Disorder Society Rating Scale Program Committee methodology, the World Health Organization concepts, and the ABC taxonomy of medication adherence. The certainty of the evidence will be determined using the modified GRADE recommendations.

Systematic review registration number:

PROSPERO (CRD42021211099)
Rotordynamic Characteristics of the Straight-Through Labyrinth Seal Based on the Applicability Analysis of Leakage Models Using Bulk-Flow Method
Authors: Wang Tianhao , Li Zhigang , Li Jun
Published: August 2021

Labyrinth seals are widely applied in the turbomachinery to control the leakage flow through the clearance between stationary and rotating components. The fluid excitation induced by the labyrinth seal would deteriorate the stability of turbomachinery shaft. Developing an accurate and rapid prediction approach is crucial to the analysis of the fluid excitation rotordynamics of labyrinth seals. The objective of this study is to analyze the applicability of leakage models using Bulk-Flow method and investigate the factors affecting the rotordynamic characteristics of the labyrinth seal. An elliptical orbit for rotor whirling was assumed in the one-control-volume Bulk-Flow model considering an isentropic process to predict the frequency-dependent rotordynamic coefficients of the labyrinth seal. The optimal leakage model was determined by comprehensively analyzing the applicability of seventy-two leakage models. Employing the optimal leakage model in the Bulk-Flow method, the effects of sealing clearance, pressure ratio, preswirl ratio and rotational speed on the rotordynamic characteristics of the labyrinth seal were investigated. The conclusions show that the Bulk-Flow method has an average prediction error of around 10% for the leakage flow rate, cross-coupled stiffness and direct damping when equipped with the optimal leakage model. Increasing preswirl ratio has a significantly destabilizing effect on the rotor stability, while the influence of increasing rotational speed is strongly related to preswirl direction. The effective damping of the labyrinth seal is sensitive to the inlet pressure, but insensitive to the outlet pressure and sealing clearance. The crossover frequency is almost impervious to the inlet pressure, outlet pressure and sealing clearance.
Acoustic modes of rapidly rotating ellipsoids subject to centrifugal gravity
Authors: Vidal Jérémie , Cébron David
Published: August 2021

The acoustic modes of a rotating fluid-filled cavity can be used to determine the effective rotation rate of a fluid (since the resonant frequencies are modified by the flows). To be accurate, this method requires a prior knowledge of the acoustic modes in rotating fluids. Contrary to the Coriolis force, centrifugal gravity has received much less attention in the experimental context. Motivated by on-going experiments in rotating ellipsoids, we study how global rotation and buoyancy modify the acoustic modes of fluid-filled ellipsoids in isothermal (or isentropic) hydrostatic equilibrium. We go beyond the standard acoustic equation, which neglects solid-body rotation and gravity, by deriving an exact wave equation for the acoustic velocity. We then solve the wave problem using a polynomial spectral method in ellipsoids, which is compared with finite-element solutions of the primitive fluid-dynamic equations. We show that the centrifugal acceleration has measurable effects on the acoustic frequencies when MΩ≳0.3, where MΩ is the rotational Mach number defined as the ratio of the sonic and rotational time scales. Such a regime can be reached with experiments rotating at a few tens of Hz by replacing air with a highly compressible gas (e.g., SF6 or C4F8).
Contrast sensitivity and quality of life following intravitreal ranibizumab injection for central retinal vein occlusion
Authors: Murakami Tomoya , Okamoto Fumiki , Sugiura Yoshimi , Morikawa Shohei , Okamoto Yoshifumi , Hiraoka Takahiro , Oshika Tetsuro
Published: August 2021

Synopsis/precis

We investigated the relationship between contrast sensitivity (CS) and vision-related quality of life (VR-QOL) in patients with central retinal vein occlusion following ranibizumab intravitreal injection; CS showed a stronger association with VR-QOL than visual acuity.

Background/aims

To investigate the relationship between CS, VR-QOL and optical coherence tomography (OCT) findings in patients with cystoid macular oedema secondary to central retinal vein occlusion (CRVO-CMO) following intravitreal injection of ranibizumab.

Methods

This was a multicentre, open-label, single-arm, prospective study. The study included 23 patients with CRVO-CMO who were followed up for 12 months after treatment. The best-corrected visual acuity (BCVA), letter contrast sensitivity (LCS) and OCT images were obtained every month. For VR-QOL assessment, the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) was administered to the patients before treatment and at 3, 6 and 12 months following treatment.

Results

The LCS and VFQ-25 composite score improved significantly from baseline to 12 months following treatment. The multiple regression analysis revealed that the LCS of the affected eye and BCVA of the fellow eye were related to the VFQ-25 composite score following treatment. The LCS improvement showed a significant correlation with the improvement in the VFQ-25 composite score, whereas the BCVA improvement was not correlated with the improvement in the VFQ-25 composite score. Stepwise multiple regression analyses revealed that, at the time of macular oedema resolution, the distance between the external limiting membrane and retinal pigment epithelium (ELM-RPE) and average ganglion cell-inner plexiform layer (GCIPL) thickness were associated with LCS.

Conclusion

CS had a stronger association with VR-QOL than with BCVA in patients with CRVO-CMO. With the resolution of macular oedema, CS was associated with ELM-RPE thickness and average GCIPL thickness.
Enhanced recovery after surgery (ERAS) in patients undergoing emergency laparotomy after trauma: a prospective, randomized controlled trial
Authors: Purushothaman Vijayan , Priyadarshini Pratyusha , Bagaria Dinesh , Joshi Mohit , Choudhary Narendra , Kumar Abhinav , Kumar Subodh , Gupta Amit , Mishra Biplab , Mathur Purva , Sagar Sushma
Published: August 2021

Background

The role of enhanced recovery after surgery (ERAS) has been established in elective operations. However, its role in emergency operations especially in trauma is under-recognized. The aim of this study was to explore the safety and efficacy of ERAS program in patients undergoing emergency laparotomy for trauma.

Methods

In this single-center study, patients who underwent emergency laparotomy after trauma were randomized to the ERAS protocol or conventional care. The ERAS protocol included early removal of catheters, early initiation of diet, use of postoperative prophylaxis and optimal usage of analgesia. The primary endpoint was duration of hospital stay. The secondary endpoints were recovery of bowel function, pain scores, complications and readmission rate.

Results

Thirty patients were enrolled in each arm. The ERAS group had significant reduction in duration of hospital stay (3.3±1.3 vs. 5.0±1.7; p<0.01). Time to remove nasogastric tube (1.1±0.1 vs. 2.2±0.9; p<0.01), urinary catheter (1.1±0.1 vs. 3.5±1.6; p<0.01), and drain (1.0±0.2 vs. 3.7±1.6; p<0.01) was shorter in the ERAS group. In ERAS group, there was earlier initiation of liquid diet (1.1±0.1 vs. 2.3±1.0; p<0.01) and solid diet (2.1±0.1 vs. 3.6±1.3; p<0.01). The usage of epidural analgesia (63% vs. 30%; p=0.01), non-steroidal anti-inflammatory drugs (93% vs. 67%; p-0.02) and deep vein thrombosis prophylaxis (100% vs. 70%; p<0.01) was higher in the ERAS group. There was no difference in the recovery of bowel function (2.4±1.0 vs. 2.1±0.9; p=0.15), pain scores (3.2±1.0 vs. 3.1±1.1; p=0.87), complications (27% vs. 23%; p=0.99) and readmission rates (07% vs. 10%; p=0.99) between the two groups.

Conclusion

ERAS protocol, when implemented in patients undergoing laparotomy for trauma, has decreased duration of hospital stay with no additional complications.

Level of evidence

Level 1, randomized controlled trial, care management.

Trial registration number

Clinical Trials Registry of India (CTRI/2019/06/019533).
Evaluation of horizontal submarine slide impact force on pipeline via a modified hybrid geotechnical – fluid dynamics framework
Authors: Fan Ning , Zhang Wangcheng , Sahdi Fauzan , Nian Tingkai
Published: August 2021

There are situations in offshore energy development where potential impact forces between submarine slides and pipelines need to be estimated. The horizontal slide – pipeline impact force, parallel to the main travel direction of the sliding mass and normal to the pipeline axis, is generally dominant compared with other force components and hence of particular concern. In practice, pipelines may be suspended at varying distances above the seabed (gap) and existing methods do not consider how this will affect the horizontal slide – pipeline forces. This paper investigates the effects of pipeline–seabed gap and pipeline diameter on the horizontal slide – pipeline impact force via 181 computational fluid dynamics (CFD) simulations at Reynolds numbers of 0.36–287. Results show that variation in the pipeline–seabed gap and pipeline diameter alters the slide mass flow behaviour as it flows past the pipeline and hence the impact force when the pipeline–seabed gap is below a critical value. A modified hybrid geotechnical – fluid dynamics framework for estimating the horizontal impact force is proposed by considering the effects of the pipeline–seabed gap and pipeline diameter, which is validated with existing experimental datasets.
Evidence of starch accumulation in tobacco Bright Yellow (TBY-2) cells in the presence of auxin
Authors: Ambrosini Veronica , Issawi Mohammad , Riou Catherine
Published: August 2021

Tobacco Bright Yellow (TBY-2) cell suspension is known to produce starch when cultured in a medium supplemented with cytokinin or in a hormone-free medium. Unexpectedly, TBY-2 cells continuously cultivated in the presence of auxin alone were also able to accumulate starch at the beginning of a stationary growth phase, with a yield of 9.22% ± 0.68%. This starch production was strongly correlated with a 25-fold increase in starch synthase activity. Moreover, this TBY-2 line was able to produce an amylopectin-rich starch with a ratio of amylopectin over amylose of 2.7, which was also linked to typical small granules (1.4 µm). According to our preliminary results, this plant cell suspension could yield a low-cost, amylopectin-rich starch — which is needed in the food industry to produce edible film or bioplastic — without being impacted by climate or seasonal weather changes.
Temporal variation in the niche partitioning of Lake Michigan salmonines as it relates to alewife abundance and size structure
Authors: Turschak Benjamin , Bronte Charles R. , Czesny Sergiusz , Gerig Brandon , Happel Austin , Höök Tomas O. , Kornis Matthew S. , Leonhardt Benjamin S. , Matthias Bryan G. , Rinchard Jacques , Bootsma Harvey
Published: August 2021

Stable isotope analyses offer a useful means for quantifying ecological niche dimensions, though few studies have examined isotopic response of an ecological community with respect to resource gradients such as fluctuations in prey availability. Stable carbon and nitrogen isotopes were measured for Lake Michigan salmonines and their prey collected from 2014 to 2016. Bayesian ellipse and mixing model analyses were used to quantify isotopic niche characteristics and diets, respectively, among species and years. During the 3-year study period, abundance and size structure of preferred alewife (Alosa pseudoharengus) prey changed substantially and offered an opportunity to explore predator isotopic niche response and diet shifts along a prey resource gradient. Results suggested increased reliance on alewives, especially small alewives, over the study period and were consistent with greater availability of this prey. However, differential use of alewife size classes and alternative prey sources by salmonine predators was apparent, which suggested possible resource partitioning. Characterization of ecological niche overlap using stable isotopes likely requires consideration of shared resource availability as well as specific prey and habitat preferences.
CRUDE OIL PRICE VOLATILITY AND ECONOMIC GROWTH: MEDIATING ROLE OF MACROECONOMIC INDICATORS
Authors: CHIEN FENGSHENG , CHAU KA YIN , JALEES TARIQ , ZHANG YUNQIAN , NGUYEN VAN CHIEN , BALOCH ZULFIQAR ALI
Published: August 2021

This study examines the correlation between oil price fluctuation and absolute business development in Pakistan. Our study focusses on three economic sectors, agriculture and livestock, manufacturing and electricity production and transportation from 1980 to 2018 using the autoregressive distributed lag, with linear regression to evaluate the (time series or panel) data (please elaborate the frequency of data as well either it is daily, weekly, monthly, quarterly or yearly data). Our findings reveal negative impact of oil price on the economic development overall, and manufacturing, electricity production and livestock sectors individually; while, there is positive relationship observed with communication and transport sectors. There is need for policymaker’s attention on highly oil-dependent sectors to run their operations. Empirical findings suggest a 30% shortage of oil supply responsible for the highest fluctuated structure of oil pricing, which suddenly increases the projected welfare loss through a 40% reduction in gross domestic product. This study suggests that the country should maintain a minimum 100-day strategic petroleum reserves to hedge any adverse effect of oil price fluctuation on economic and social welfare losses.
The Light Extraction Efficiency of GaN-based LED with Air-Hole Photonic Crystal Structures
Authors: Ge Daohan , Hu Zhou , Gao Kai , Zhang Liqiang
Published: August 2021

In order to improve the light extraction efficiency (LEE) of GaN-based light-emitting diodes (LEDs), a layer of cylindrical air-hole photonic crystal (PC) structure inserted into P-GaN is proposed and investigated numerically. Finite difference time domain (FDTD) method is used to make a series of simulations in the LEE of GaN-based LED with air-hole photonic crystal structure. According to the variable-controlling approach, the PC structure is simulated and optimized. The results of the simulations show that the LEE depends on the PC’s position and relevant structural parameters. When PC is etched in the active layer, and its dielectric constant [Formula: see text][Formula: see text][Formula: see text]m, etching [Formula: see text][Formula: see text][Formula: see text]m and air-hole radius [Formula: see text][Formula: see text][Formula: see text]m, higher LEE is obtained as 44.5%, translated into a 13.6-fold enhancement for the case of a planar LED. The remarkable enhancement is of particular interest for improving LEE of LED and provides a theoretical reference for future LED structure design efforts.
Mathematical modeling of the impact of temperature variations and immigration on malaria prevalence in Nigeria
Authors: Ukwajunor Eunice E. , Akarawak Eno E. E. , Abiala Israel Olutunji
Published: August 2021

The study examines the population-level impact of temperature variability and immigration on malaria prevalence in Nigeria, using a novel deterministic model. The model incorporates disease transmission by immigrants into the community. In the absence of immigration, the model is shown to exhibit the phenomenon of backward bifurcation. The disease-free equilibrium of the autonomous version of the model was found to be locally asymptotically stable in the absence of infective immigrants. However, the model exhibits an endemic equilibrium point when the immigration parameter is greater than zero. The endemic equilibrium point is seen to be globally asymptotically stable in the absence of disease-induced mortality. Uncertainty and sensitivity analysis of the model, using parameter values and ranges relevant to malaria transmission dynamics in Nigeria, shows that the top three parameters that drive malaria prevalence (with respect to [Formula: see text]) are the mosquito natural death rate ([Formula: see text]), mosquito biting rate ([Formula: see text]) and the transmission rates between humans and mosquitoes ([Formula: see text]). Numerical simulations of the model show that in Nigeria, malaria burden increases with increasing mean monthly temperature in the range of 22–28[Formula: see text]. Thus, this study suggests that control strategies for malaria should be intensified during this period. It is further shown that the proportion of infective immigrants has marginal effect on the transmission dynamics of the disease. Therefore, the simulations suggest that a reduction in the fraction of infective immigrants, either exposed or infectious, would significantly reduce the malaria incidence in a population.
Global stability of a within-host SARS-CoV-2/cancer model with immunity and diffusion
Authors: Elaiw A. M. , Al Agha A. D. , Alshaikh M. A.
Published: August 2021

Coronavirus disease 2019 (COVID-19) is a new respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It started in China and spread quickly to all continents. This virus has changed the life style and the education system in many countries. As for other viruses, mathematical models have been rated as a useful tool to support the research on COVID-19. In this work, we develop a reaction–diffusion model to describe the within-host dynamics of SARS-CoV-2 in cancer patients. This model studies the interactions between nutrient, healthy epithelial cells, cancer cells, SARS-CoV-2 particles, and immune cells. The model incorporates the spatial mobility of the cells and viruses. The model includes parameters for measuring the effect of lymphopenia on SARS-CoV-2/cancer patients. We verify the basic features of the model’s solutions including the uniqueness, nonnegativity and boundedness. We list all equilibrium points of the proposed model. We show the global stability and the local instability of the most meaningful equilibria. We display some numerical simulations to enhance our theoretical results. The results indicate that diffusion can have a clear effect at the beginning of SARS-CoV-2 infection. Lymphopenia in SARS-CoV-2/cancer patients impairs the immune responses against cancer and SARS-CoV-2, and worsens the health state of patients.
Mn3O4@MnS composite nanoparticles as cathode materials for aqueous rechargeable Zn ion batteries
Authors: Gao Xingyuan , Li Haodong , Cao Xianshuo , Lu Xihong
Published: August 2021

Exploring high-capacity and stable cathode materials for aqueous rechargeable Zn ion batteries (ZIBs) is highly attractive but challenging. Herein, we present a kind of Mn3O4@MnS heterostructured nanoparticle as a robust ZIB cathode. These Mn3O4@MnS nanoparticles are facilely synthesized by in-situ transformation of MnO2 under sulfidation thermal treatment. Owing to the heterostructured architecture and improved electrical conductivity, the as-obtained Mn3O4@MnS nanoparticles afford a stable capacity of 128.3 mA h g[Formula: see text] at 2 mA cm[Formula: see text] and good stability of more than 65% capacity retention after 1000 cycles. Additionally, a remarkably energy density of 184.72 Wh kg[Formula: see text] is also achieved by the assembled Zn//Mn3O4@MnS battery. This work paves the way for constructing Mn-based heterostructures as high-performance cathodes in aqueous ZIBs.
Experimental high thoracic spinal cord injury impairs the cardiac and cerebrovascular response to orthostatic challenge in rats
Authors: Hayes Brian D. , Fossey Mary Pauline Mona , Poormasjedi-Meibod Malihe-Sadat , Erskine Erin , Soriano Jan Elaine , Scott Berkeley , Rosentreter Ryan , Granville David J. , Phillips Aaron A. , West Christopher R.
Published: August 2021

This is the first use of LBNP to interrogate the cardiac and cerebrovascular responses to simulated OH in a preclinical study of SCI. Here, we demonstrate the utility of our simulated OH model and use it to demonstrate that SCI impairs the cardiac response to simulated OH and disrupts dynamic cerebrovascular autoregulation.
[Retracted] Deep Convolutional Neural Network and Weighted Bayesian Model for Evaluation of College Foreign Language Multimedia Teaching
Authors: Liu Tingting , Ning Le
Published: August 2021

In colleges and universities, teaching quality evaluation is an integral part of the teaching management process. Many factors influence it, and the relationship between its evaluation index and instructional quality is complicated, abstract, and nonlinear. However, existing evaluation methods and models have flaws such as excessive subjectivity and randomness, difficulty determining the weight of indicators, easy over‐fitting, slow convergence speed, and limited computing power, to name a few. Furthermore, the evaluation index system focuses primarily on teaching attitude, material, and methods, rarely taking into account preparation prior to teaching or the teaching situation throughout the teaching process, resulting in an incomplete evaluation. As a result, learning how to construct a model for objectively, truly, thoroughly, and accurately assessing the teaching quality of colleges and universities is beneficial not only to improving teaching quality but also to promoting scientific decision‐making in education. This paper develops a teaching assessment model using a deep convolutional neural network and the weighted Naive Bayes algorithm. Based on the degree of influence of different characteristics on the assessment outcomes, a method to estimate the weight of each evaluation characteristic by employing the related probability of class attributes is proposed, and the corresponding weight is assigned for each evaluation index, resulting in a classification model ideal for teaching assessment that promotes standardization and intelligibility.
Research on Supernetwork Equilibrium about Deep Convergence of Enterprise Alliance for Breakthrough Innovation
Authors: Liu Yumei , Wen Xin , Meng Xiangfei
Published: August 2021

The realization of breakthrough innovation with high risk and uncertainty has always been the focus of the theory and practice of technological innovation. Based on the supernetwork theory, this paper constructs a supernetwork equilibrium model about deep convergence of enterprise alliance for breakthrough innovation and uses numerical simulation tools to find out the equilibrium conditions for deep convergence of enterprise alliance in different stages of breakthrough innovation. It is not only conducive to understand the process of enterprise alliance’s deep convergence in “Creativity-Research-Production-Sales” but also helpful to understand the roles that deep convergence in enterprise alliance can play in achieving breakthrough innovation. It not only expands the existing research on breakthrough innovation but also provides a scientific reference for the deep convergence of enterprise alliance in practice.
Improving Land Use Planning through the Evaluation of Ecosystem Services: One Case Study of Quyang County
Authors: Liu Lin , Zhou Yapeng , Yin Haikui , Zhang Ruiqiang , Ma Ying , Zhang Guijun , Zhao Pengfei , Feng Jinxiong
Published: August 2021

Competition for land is increasing as demand for multiple land uses and ecosystem services rises. Land regulation of the principles of landscape ecology is necessary to develop more sustainable approaches to land use planning. The research evaluated the present land patterns and determined best practices for its regulation of Dongwang Township in Quyang County, located in the Taihang Mountain area of Hebei Province, China. The research used the landscape ecology theory to construct an index system for landscape pattern analysis based on the GIS and Fragstats 3.3 software. In this study, we examined the specific reasons that landscape ecology is superior to traditional methods in land consolidation planning and design, which is conducive to the comprehensive development of land ecological benefits. Landscape ecological planning can effectively reduce landscape fragmentation and improve intensive management. The result found that the descending order of the Shannon index was current landscape, landscape ecological planning, and traditional planning. Landscape ecological planning could protect the natural diversity than traditional planning. Landscape ecological planning enables the creation of long corridors, with higher densities and connectivity and lower average corridor widths than traditional planning. Besides, it can improve ecological service function values in the study area to varying degrees, thus discouraging residents from limiting themselves to grain production. This research has great potential to improve the visibility of ecosystem services in local land use planning and, thus, to improve the ecological functioning of future landscapes.
lncRNA MAGI2-AS3 Exerts Antioncogenic Roles in Hepatocellular Carcinoma via Regulating the miR-519c-3p/TXNIP Axis
Authors: Wei Huamei , Tang Qianli , Wang Anmin , Zhang Ya , Qin Zebang , Li Wenchuan , Xu Zuoming , Wang Jianchu , Pu Jian
Published: August 2021

Introduction. Our work was aimed to explore the mechanisms of MAGI2 antisense RNA 3 (MAGI2-AS3) in regulating hepatocellular carcinoma (HCC) carcinogenesis. Methods. MAGI2-AS3, microRNA-519c-3p (miR-519c-3p), and thioredoxin interacting protein (TXNIP) levels in HCC were detected by the RT-qPCR method. Cell proliferation and apoptosis rate were measured using Cell Counting Kit-8 assay and flow cytometry assay. Relationship between MAGI2-AS3, TXNIP, and miR-519c-3p were analyzed via luciferase activity assay, RNA pull-down assay, and RNA immunoprecipitation assay. Mouse xenograft models of HCC were conducted to explore the roles of MAGI2-AS3 in vivo. Results. MAGI2-AS3 levels were elevated, and miR-519c-3p decreased in HCC. MAGI2-AS3 overexpression inhibits while its knockdown stimulates HCC cell growth through miR-519c-3p. Moreover, miR-519c-3p overexpression stimulates HCC cell growth. MAGI2-AS3 serves as competing endogenous RNA (ceRNA) of miR-519c-3p to regulate TXNIP in HCC. And, TXNIP upregulation weakened the influence of MAGI2-AS3 knockdown on HCC cell behaviors. Additionally, MAGI2-AS3 overexpression suppressed HCC tumor growth in vivo. Conclusion. MAGI2-AS3 inhibits HCC tumorigenesis through miR-519c-3p/TXNIP axis in vitro and in vivo, indicating MAGI2-AS3 plays a crucial role in HCC development.
Biomechanics in Removable Partial Dentures: A Literature Review of FEA‐Based Studies
Authors: Mousa Mohammed A. , Abdullah Johari Yap , Jamayet Nafij B. , El-Anwar Mohamed I. , Ganji Kiran Kumar , Alam Mohammad Khursheed , Husein Adam
Published: August 2021

The present study was aimed at reviewing the studies that used finite element analysis (FEA) to estimate the biomechanical stress arising in removable partial dentures (RPDs) and how to optimize it. A literature survey was conducted for the English full‐text articles, which used only FEA to estimate the stress developed in RPDs from Jan 2000 to May 2021. In RPDs, the retaining and supporting structures are subjected to dynamic loads during insertion and removal of the prosthesis as well as during function. The majority of stresses in free‐end saddle (FES) RPDs are concentrated in the shoulder of the clasp, the horizontal curvature of the gingival approaching clasp, and the part of the major connector next to terminal abutments. Clasps fabricated from flexible materials were beneficial to eliminate the stress in the abutment, while rigid materials were preferred for major connectors to eliminate the displacement of the prosthesis. In implant‐assisted RPD, the implant receive the majority of the load, thereby reducing the stress on the abutment and reducing the displacement of the prosthesis. The amount of stress in the implant decreases with zero or minimal angulation, using long and wide implants, and when the implants are placed in the first molar area.
How Different Motivations for Making Informal Out‐Of‐Pocket Payments Vary in Their Influence on Users’ Satisfaction with Healthcare, Local and National Government, and Satisfaction with Life?
Authors: Habibov Nazim , Auchynnikava Alena , Fan Lida , Lyu Yunhong
Published: August 2021

Background. The dominant view in the literature is that informal payments in healthcare universally are a negative phenomenon. By contrast, we theorize that the motivation healthcare users for making informal payments (IP) can be classified into three categories: (1) a cultural norm, (2) “grease the wheels” payments if users offered to pay to get better services, and (3) “sand the wheels” payments if users were asked to pay by healthcare personnel or felt that payments were expected. We further hypothesize that these three categories of payments are differently associated with a user’s outcomes, namely, satisfaction with healthcare, local and national government, satisfaction with life, and satisfaction with life of children in the future. Methods. We used microdata from the 2016 Life‐in‐Transition survey. Multivariate regression analysis is used to quantify relationships between these categories of payments and users’ outcomes. Results. Payments that are the result of cultural norms are associated with better outcomes. On the contrary, “sand the wheel” payments are associated with worse outcomes. We find no association between making “grease the wheels” payments and outcomes. Conclusions. This is the first paper which evaluates association between three different categories of informal payments with a wide range of users’ outcomes on a diverse sample of countries. Focusing on informal payments in general, rather than explicitly examining specific motivations, obscures the true outcomes of making IP. It is important to distinguish between three different motivations for informal payment, namely, cultural norms, “grease the wheels,” and “sand the wheels” since they have varying associations with user outcomes. From a policy making standpoint, variation in the links between different motivations for making IP and measures of satisfaction suggest that decision‐makers should put their primary focus on situations where IP are explicitly asked for or are implied by the situation and that they should differentiate this from cases of gratitude payments. If such measures are not implemented, then policy makers may unintentionally ban the behaviour that is linked with increased satisfaction with healthcare, government, and life (i.e., paying gratitude).
Comparison of Dexmedetomidine and Etomidate on Intraoperative Wake-Up Equality, Hemodynamics, and Cerebral Protection in Operation of the Brain Functional Area
Authors: Peng Yuerong , Guan Qinglai
Published: August 2021

In recent years, with the increasing incidence of brain functional area tumors, the clinical application of functional area tumor resection has become extremely urgent. Intraoperative wake-up is an important auxiliary method of this operation, which can effectively reduce the damage of the brain function area caused by the operation and anesthesia itself while playing the role of auxiliary function area and tumor positioning. However, the intraoperative wake-up requires a higher anesthesia effect, so higher requirements are put forward for the choice of anesthetic drugs. Based on hemodynamic and serum molecular observations, this study found that dexmedetomidine- and etomidate-assisted anesthesia were used for intraoperative wake-up in brain functional area surgery, both of which could maintain hemodynamic stability. In addition, the arousal effect and brain protection of dexmedetomidine were better than those of etomidate, and the incidence of adverse reactions was lower during the arousal period. This can provide relevant reference for clinical improvement of the anesthesia effect and surgical safety of intraoperative wake-up.