bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple Intraspinal Gangliogliomas in a Child With Neurofibromatosis Type 1: Case Report and Literature Review
Authors: Morales Erin , Viskochil David , Hofmann Jeffrey , Hagedorn Caroline , Linscott Luke , Cheshier Samuel , Bruggers Carol S.
Published: January 2021

Neurofibromatosis type 1 (NF1)-associated primary intramedullary spinal cord ganglioglioma has only rarely been reported. Because of frequent nonresectability, they pose significant management challenges despite clinical indolence. This report describes a 4-year-old girl with NF1 who was found to have multiple discrete, infiltrative intramedullary cord masses, and biopsy demonstrated World Health Organization grade I ganglioglioma. Panel-based next-generation sequencing showed her previously identified germline NF1 mutation and a second somatic NF1 mutation. This represents the first report of multiple primary intramedullary gangliogliomas in a child with NF1 and demonstrates how biopsy with panel-based next-generation sequencing provides potential targets for MAPK/MEK/BRAF pathway inhibitor therapy.
Hyperoxia During Cardiopulmonary Bypass Is Associated With Mortality in Infants Undergoing Cardiac Surgery*
Authors: Beshish Asaad G. , Jahadi Ozzie , Mello Ashley , Yarlagadda Vamsi V. , Shin Andrew Y. , Kwiatkowski David M.
Published: January 2021

OBJECTIVES:

Patients undergoing cardiac surgery using cardiopulmonary bypass have variable degrees of blood oxygen tension during surgery. Hyperoxia has been associated with adverse outcomes in critical illness. Data are not available regarding the association of hyperoxia and outcomes in infants undergoing cardiopulmonary bypass. We hypothesize that among infants undergoing cardiac surgery, hyperoxia during cardiopulmonary bypass is associated with greater odds of morbidity and mortality.

DESIGN:

Retrospective study.

SETTING:

Single center at an academic tertiary children’s hospital.

PATIENTS:

All infants (< 1 yr) undergoing cardiopulmonary bypass between January 1, 2015, and December 31, 2017, excluding two patients who were initiated on extracorporeal membrane oxygenation in the operating room.

INTERVENTIONS:

None.

MEASUREMENTS AND MAIN RESULTS:

The study included 469 infants with a median age of 97 days (interquartile range, 14–179 d), weight 4.9 kg (interquartile range, 3.4–6.4 kg), and cardiopulmonary bypass time 128 minutes (interquartile range, 91–185 min). A Pao
2 of 313 mm Hg (hyperoxia) on cardiopulmonary bypass had highest sensitivity with specificity greater than 50% for association with operative mortality. Approximately, half of the population (237/469) had hyperoxia on cardiopulmonary bypass. Infants with hyperoxia were more likely to have acute kidney injury, prolonged postoperative length of stay, and mortality. They were younger, weighed less, had longer cardiopulmonary bypass times, and had higher Society of Thoracic Surgeons and the European Association for Cardio-Thoracic Surgery mortality scores. There was no difference in sex, race, preoperative creatinine, single ventricle physiology, or presence of genetic syndrome. On multivariable analysis, hyperoxia was associated with greater odds of mortality (odds ratio, 4.3; 95% CI, 1.4–13.2) but failed to identify an association with acute kidney injury or prolonged postoperative length of stay. Hyperoxia was associated with greater odds of mortality in subgroup analysis of neonatal patients.

CONCLUSIONS:

Hyperoxia occurred in a substantial portion of infants undergoing cardiopulmonary bypass for cardiac surgery. Hyperoxia during cardiopulmonary bypass was an independent risk factor for mortality and may be a modifiable risk factor. Furthermore, hyperoxia during cardiopulmonary bypass was associated with four-fold greater odds of mortality within 30 days of surgery. Hyperoxia failed to identify an association with development of acute kidney injury or prolonged postoperative length of stay when controlling for covariables. Validation of our data among other populations is necessary to better understand and elucidate potential mechanisms underlying the association between excess oxygen delivery during cardiopulmonary bypass and outcome.
Effect of Context-Dependent Modulation of Trunk Muscle Activity on Manual Wheelchair Propulsion
Authors: Bailey Stephanie Nogan , Foglyano Kevin M. , Bean Nicholas F. , Triolo Ronald J.
Published: January 2021

Objective

The aims of the study were to reliably determine the two main phases of manual wheelchair propulsion via a simple wearable sensor and to evaluate the effects of modulated trunk and hip stimulation on manual wheelchair propulsion during the challenging tasks of ramp assent and level sprint.

Design

An offline tool was created to identify common features between wrist acceleration signals for all subjects who corresponded to the transitions between the contact and recovery phases of manual wheelchair propulsion. For one individual, the acceleration rules and thresholds were implemented for real-time phase-change event detection and modulation of stimulation.

Results

When pushing with phase-dependent modulated stimulation, there was a significant (P < 0.05) increase in the primary speed variable (5%–6%) and the subject rated pushing as “moderately or very easy.” In the offline analysis, the average phase-change event detection success rate was 79% at the end of contact and 71% at the end of recovery across the group.

Conclusions

Signals from simple, wrist-mounted accelerometers can detect the phase transitions during manual wheelchair propulsion instead of elaborate and expensive, instrumented systems. Appropriately timing changes in muscle activation with the propulsion cycle can result in a significant increase in speed, and the system was consistently perceived to be significantly easier to use.
The Physiatry Workforce in 2019 and Beyond, Part 1
Authors: Forte Gaetano J. , Langelier Margaret , Wang Shen , Dall Timothy M. , Reynolds Ryan L. , Chakrabarti Ritashree , Whyte John , Ankam Nethra Sridhara , Annaswamy Thiru M. , Fredericson Michael , Jain Nitin B. , Karimi Danielle Perret , Morgenroth David C. , Slocum Chloe , Wisotzky Eric
Published: January 2021

Objective

The aim of the study was to describe the current physiatrist workforce in the United States.

Design

An online, cross-sectional survey of board-certified physiatrists in 2019 (N = 616 completed, 30.1% response) collected information about demographic and practice characteristics, including age, sex, practice area, practice setting, hours worked, patient characteristics, staffing, and work responsibilities. Physiatrists were stratified by substantive practice patterns using a cluster analysis approach. Survey responses were arrayed across the practice patterns and differences noted.

Results

The practice patterns identified included musculoskeletal/pain medicine, general/neurological rehabilitation, academic practice, pediatric rehabilitation, orthopedic/complex conditions rehabilitation, and disability/occupational rehabilitation. Many differences were observed across these practice patterns. Notably, primary practice setting and the extent and ways in which other healthcare staff are used in physiatry practices differed across practice patterns. Physiatrists working in musculoskeletal/pain medicine and disability/occupational rehabilitation were least likely to work with nurse practitioners and physician assistants. Physiatrists working in academic practice, general/neurological rehabilitation, and pediatric rehabilitation were most likely to have primary practice settings in hospitals.

Conclusions

Physiatry is an evolving medical specialty affected by many of the same trends as other medical specialties. The results of this survey can inform policy discussions and further research on the effects of these trends on physiatrists and physiatry practice in the future.
Evaluating Alzheimer Disease With Flortaucipir and Florbetapir PET
Authors: James Olga G. , Linares Alexandra R. , Hellegers Caroline , Doraiswamy P. Murali , Wong Terence Z.
Published: January 2021

Early, accurate diagnosis of Alzheimer disease (AD) is essential but remains challenging. Neuropathological hallmarks of AD are β-amyloid neuritic plaques and tau protein neurofibrillary tangles. 18F-Florbetapir is one of several available PET tracers for imaging cortical fibrillary β-amyloid plaques. 18F-Flortaucipir PET was recently approved for evaluating the distribution and density of aggregated neurofibrillary tangles. We present cases of mild cognitive impairment or suspected AD to depict the nuances of flortaucipir distribution and scan interpretation as well as how combined information from amyloid and tau PET may help with differential diagnosis and prognosis.
Chronic Illness and Fatigue in Older Individuals: A Systematic Review
Authors: Torossian Maral , Jacelon Cynthia S.
Published: January 2021

Background

Fatigue is a symptom experienced by 40%–74% of older individuals in the United States. Despite its significance, clinicians face challenges helping individuals to manage or reduce fatigue levels. Some management issues are attributable to the ambiguity around the risk factors, consequences, and the effect of fatigue management strategies.

Methods

A literature review was conducted using four databases to identify themes in relation to risk factors, consequences, and management strategies from research studies about fatigue in older individuals with chronic diseases.

Results

Findings on fatigue risk factors, such as age, body mass index, and marital status, were contradictory. There was a positive association between fatigue and comorbidities, depression, and anxiety and a negative relationship between fatigue and physical activity, sleep, educational status, and socioeconomic status. Fatigue was perceived as a state of “feebleness” and negatively impacted individuals’ quality of life. Consequences of fatigue included tiredness, sleepiness, depression, anxiety, worse sense of purpose in life, poor self-care, and an increased β-amyloid load. Predictors of worse fatigue consequences included functional health, symptom burden, subjective health, and self-acceptance. Fatigue management strategies included physical activity, rest, sleep, maintaining normal hemoglobin levels, and acetyl-l-carnitine supplementation.

Conclusion

This systematic review is of value to older individuals with chronic illnesses, researchers, and clinicians who strive to improve the quality of life of individuals experiencing fatigue. To prevent undesirable consequences of fatigue, older individuals should be screened for the discussed modifiable risk factors of fatigue. The inconsistencies in the studies reviewed can guide researchers to potential research areas that require further inquiry and exploration to ground future practice on best scientific evidence
The Role of Disease Acceptance, Life Satisfaction, and Stress Perception on the Quality of Life Among Patients With Multiple Sclerosis: A Descriptive and Correlational Study
Authors: Kołtuniuk Aleksandra , Pytel Aleksandra , Kulik Anna , Rosińczuk Joanna
Published: January 2021

Purpose

The aim of this study was to evaluate the relationship between illness acceptance, life satisfaction, stress intensity, and their impact on the quality of life (QOL) in patients with multiple sclerosis (MS).

Design

Descriptive and correlational study.

Methods

A group of 100 patients with MS responded to the Expanded Disability Status Scale, the World Health Organization Quality of Life Brief (WHOQOL-BREF) Scale, the Acceptance of Illness Scale (AIS), the Perceived Stress Scale (PSS-10), the Satisfaction With Life Scale (SWLS), and a sociodemographic questionnaire.

Findings

A significant relationship was shown between the mean scores of AIS, SWLS, PSS-10, and WHOQOL-BREF; however, there was no relationship between the mean scores of AIS, SWLS, PSS-10, WHOQOL-BREF and the Expanded Disability Status Scale.

Conclusion

Quality of life in patients with MS is positively affected by higher level of disease acceptance and life satisfaction as well as a lower level of perceived stress.

Clinical Relevance

Rehabilitation nurses should consider the patient’s disease acceptance, QOL, perceived stress, disability level, and satisfaction of life in planning and implementing a comprehensive rehabilitation plan.
Development and Validation of a Resilience Questionnaire for Patients During Stroke Rehabilitation in China
Authors: Cai Lian-huan , Zhang Qi , Pang Shu-qin , Chen Hui , Li Ming
Published: January 2021

Purpose

The aim of the study was to develop a comprehensive questionnaire for assessing resilience in patients with stroke during rehabilitation and examine the questionnaire’s reliability and validity.

Design

A four-phased design was used to develop and validate the questionnaire.

Methods

The preliminary items of the Resilience Questionnaire for Stroke Rehabilitation (RQSR) were generated through a literature review and a qualitative study. Twenty experts were consulted for content validation and modification of the questionnaire. A pilot study was conducted with 55 patients with stroke. A total of 510 participants from seven rehabilitation centers or hospitals were subsequently recruited to examine the psychometric properties of the RQSR.

Results

The RQSR consists of 35 items within three dimensions. Dimensions include effective rehabilitation training, accessible support system, and appropriate self-regulation. The content validity index of the total questionnaire was .9335. Seven factors were derived through factor analysis, and cumulative contribution rate of variance was 65.455%. Cronbach’s alpha of the total questionnaire was .957, with each dimension ranging from .731 to .918, demonstrating high levels of reliability.

Conclusion

The RQSR has sound reliability and validity and can be used as an appropriate tool for assessing resilience for patients with stroke during rehabilitation to facilitate effective interventions.
Introducing Standardized Assessment and Management of Oral Cares in a Rehabilitation Unit: Patient Outcomes and Experiences
Authors: Schwarz Maria , Kwiecien Inger , Hamlet Blaise , Coccetti Anne , Monsiegneur Ursula , Tickle Benjamin , Cardell Elizabeth
Published: January 2021

Purpose

The aim of this study was to improve patient oral hygiene outcomes in a rehabilitation unit by implementing a nursing education package and oral hygiene assessment tool.

Design

A case–control design with 50 rehabilitation patients was performed.

Methods

Nursing staff received education and training in applying the Modified Oral Health Assessment Tool. Clinician assessment of patient oral hygiene occurred on admission and at days 5–7. Each patient reported their perceptions of oral hygiene and comfort prior to hospitalization, while in the hospital, and after transfer to the rehabilitation unit.

Findings

Oral hygiene rating scores improved significantly from admission to the rehabilitation unit to days 5–7 (p = .00). The mean score of patient perceived cleanliness improved from hospital admission to admission to the rehabilitation unit.

Conclusion

Oral hygiene was improved following admission to a rehabilitation unit with a consistent and individualized approach to oral hygiene.

Clinical Relevance

The introduction of a consistent and individualized approach to oral hygiene demonstrates positive patient outcomes and high patient acceptance.
Brief Psychosocial Intervention to Address Poststroke Depression May Also Benefit Fatigue and Sleep–Wake Disturbance
Authors: Byun Eeeseung , Becker Kyra J. , Kohen Ruth , Kirkness Catherine J. , Mitchell Pamela H.
Published: January 2021

Purpose

This study aimed to determine if brief psychosocial/behavioral therapy directed to reduce poststroke depression would decrease fatigue and improve sleep–wake disturbance.

Design

A preplanned secondary data analysis from a completed clinical trial was conducted.

Methods

One hundred participants received usual care, in-person intervention, or telephone intervention. Depression, fatigue, and sleep–wake disturbance were measured at entry, 8 weeks, 21 weeks, and 12 months following the intervention.

Findings

Fatigue (within: p = .042, between: p = .394), sleep disturbance (within: p = .024, between: p = .102), and wake disturbance (within: p = .004, between: p = .508) decreased over the 12 months in the intervention groups, but not in the control group. This difference was clinically meaningful for wake disturbance and approached the clinically important difference for fatigue.

Conclusions/Clinical Relevance

Reduction in wake disturbance was consistent with clinically meaningful difference standards for patient-reported outcomes, warranting further research in larger samples.
Using Dorsal Metacarpal Artery Perforator Flap in the Soft Tissue Reconstruction of Traumatic Finger Defects
Authors: Chang Dun-Hao , Hsieh Chi-Ying , Chang Che-Wei , Chang Ke-Chung , Chan Chien-Lung
Published: January 2021

Introduction

The reconstruction of soft tissue defects of fingers is a challenge due to the limitations of local tissue availability. The dorsal metacarpal artery perforator (DMAP) flap is a vascular island flap raised on the dorsum of the hand, and it is a good option for finger reconstruction by replacing similar-for-similar in a single operation. In this study, we would like to share our experience of using the DMAP flap in cases of various traumatic finger defects.

Materials and Methods

From November 2016 to May 2019, patients who had traumatic finger injuries and had undergone DMAP flap for soft tissue reconstruction were examined. The patients' demographic data, injury and flap characteristics, wound healing status, and complications were collected and studied. The functional and aesthetic outcomes were evaluated using the Michigan Hand Outcomes Questionnaire.

Results

There was a total of 10 patients included in this study, of which 9 were male and 1 was female. The average age was 43 years (17–66 years). Seven patients were administered general anesthesia, and 3 others wide-awake local anesthesia. The average flap size was 4.9 × 2.0 cm, and all the donor sites were primarily closed. Nearly half of the patients had temporary venous congestion, but most of the flaps survived well ultimately. Only 1 patient had a partial flap necrosis, which required an additional skin graft.

Conclusions

The DMAP flap offers a thin and pliable skin to reconstruct finger defects within 1-stage surgery. It is easy to harvest with reliable and constant circulation. With adequate design, the DMAP flap can be used to resurface both volar and dorsal finger defects and also can reach the tip of the little finger. The DMAP flap is the ideal flap for reconstruction of traumatic finger defect with either local or general anesthesia.
Mild Alzheimer Disease, Financial Capacity, and the Role of Depression
Authors: Giannouli Vaitsa , Tsolaki Magda
Published: January 2021

The aim of this study was to assess whether comorbid depression in patients with mild Alzheimer disease (AD) can influence financial capacity. The sample comprised 109 participants divided into 4 groups: mild AD with and without depressive symptoms, and cognitive normal elderly with and without depression. Participants were examined using a number of neuropsychological tests, with an emphasis on the Mini-Mental State Examination, the 15-item Geriatric Depression Scale, and the Legal Capacity for Property Law Transactions Assessment Scale. Financial capacity ascertained as performance in the Legal Capacity for Property Law Transactions Assessment Scale in the group of mild AD patients was severely impaired when depression coexisted, thus clearly differentiating the mild AD group from mild AD with comorbid depression.
The Efficacy of Vitamin D Supplementation for Migraine: A Meta-Analysis of Randomized Controlled Studies
Authors: Zhang Yuan-feng , Xu Zhi-qiang , Zhou Hong-jie , Liu Ya-zhen , Jiang Xiao-jiang
Published: January 2021

Introduction

The efficacy of vitamin D for migraine remains controversial. We conduct a systematic review and meta-analysis to explore the influence of vitamin D versus placebo on treatment in migraine patients.

Methods

We search PubMed, EMbase, Web of Science, EBSCO, and Cochrane library databases through April 2020 for randomized controlled trials assessing the effect of vitamin D versus placebo on treatment efficacy in migraine patients. This meta-analysis is performed using the random-effect model.

Results

Five randomized controlled trials are included in the meta-analysis. Overall, compared with control group in migraine patients, vitamin D treatment is associated with substantially reduced number of headache days (standard mean difference [SMD], −0.53; 95% confidence interval [CI], −0.83 to −0.23; P = 0.0006), frequency of headache attacks (SMD, −1.09; 95% CI, −1.86 to −0.32; P = 0.006), headache severity (SMD, −0.55; 95% CI, −0.91 to −0.19; P = 0.0003), and Migraine Disability Assessment score (SMD, −0.76; 95% CI, −1.11 to −0.40; P < 0.0001).

Conclusions

Vitamin D treatment is effective to alleviate migraine.
ADF and cofilin-1 collaborate to promote cortical actin flow and the leader bleb-based migration of confined cells
Authors: Ullo Maria F. , Logue Jeremy S.
Published: January 2021

Melanoma cells have been shown to undergo fast amoeboid (leader bleb-based) migration, requiring a single large bleb for migration. In leader blebs, is a rapid flow of cortical actin that drives the cell forward. Using RNAi, we find that co-depleting cofilin-1 and ADF led to a large increase in cortical actin, suggesting that both proteins regulate cortical actin. Furthermore, severing factors can promote contractility through the regulation of actin architecture. However, RNAi of cofilin-1 but not ADF led to a significant decrease in cell stiffness. We found cofilin-1 to be enriched at leader bleb necks, whereas RNAi of cofilin-1 and ADF reduced bleb sizes and the frequency of motile cells. Strikingly, cells without cofilin-1 and ADF had blebs with abnormally long necks. Many of these blebs failed to retract and displayed slow actin turnover. Collectively, our data identifies cofilin-1 and ADF as actin remodeling factors required for fast amoeboid migration.
The three-dimensional landscape of chromatin accessibility in Alzheimer’s disease
Authors: Bendl Jaroslav , Hauberg Mads E. , Girdhar Kiran , Im Eunju , Vicari James M. , Rahman Samir , Dong Pengfei , Misir Ruth , Kleopoulos Steven P. , Reach Sarah M. , Apontes Pasha , Zeng Biao , Zhang Wen , Voloudakis Georgios , Nixon Ralph A. , Haroutunian Vahram , Hoffman Gabriel E. , Fullard John F. , Roussos Panos
Published: January 2021

Much is still unknown about the neurobiology of Alzheimer’s disease (AD). To better understand AD, we generated 636 ATAC-seq libraries from cases and controls to construct detailed genomewide chromatin accessibility maps of neurons and non-neurons from two AD-affected brain regions, the entorhinal cortex and superior temporal gyrus. By analyzing a total of 19.6 billion read pairs, we expanded the known repertoire of regulatory sequences in the human brain. Multi-omic data integration associated global patterns of chromatin accessibility with gene expression and identified cell-specific enhancer-promoter interactions. Using inter-individual variation in chromatin accessibility, we definecis-regulatory domains capturing the 3D structure of the genome. Multifaceted analyses uncovered disease associated perturbations impacting chromatin accessibility, transcription factor regulatory networks and the 3D genome, and implicated transcriptional dysregulation in AD. Overall, we applied a systematic approach to understand the role of the 3D genome in AD and to illuminate novel disease biology that can advance diagnosis and therapy.
srnaMapper: an optimal mapping tool for sRNA-Seq reads
Authors: Zytnicki Matthias , Gaspin Christine
Published: January 2021

Motivation

Sequencing is the key method to study the impact of short RNAs, which include micro RNAs, tRNA-derived RNAs, and piwi-interacting RNA, among other. The first step to make use of these reads is to map them to a genome. Existing mapping tools have been developed for the long RNAs in mind, and, so far, no tool has been conceived for short RNAs. However, short RNAs have several distinctive features which make them different from messenger RNAs: they are shorter (not greater than 200bp), they often redundant, they can be produced by duplicatedloci, and they may be edited at their ends.

Results

In this work, we present a new tool, srnaMapper, that maps these reads with all these objectives in mind. We show on two data sets that srnaMapper is more efficient considering computation time and edition error handling: it quickly retrieves all the hits, with arbitrary number of errors.

Availability

srnaMapper source code is available athttps://github.com/mzytnicki/srnaMapper.

Contact

matthias.zytnicki@inrae.fr
Alkali and alkaline earth coordination polymers constructed from benzene-1,2,4,5-tetracarboxylic acid and flexible dicarboxylate acid ligands: syntheses, structures and spectroscopic and thermal properties
Authors: Lifa Said , Trifa Chahrazed , Bouacida Sofiane , Boudaren Chaouki , Merazig Hocine
Published: January 2021

Two new metal coordination complexes, namely, poly[aqua(μ6-benzene-1,2,4,5-tetracarboxylic acid-κ8
O
1:O
1,O
2:O
2′:O
4:O
4,O
5:O
5′)(μ-but-2-enedioato-κ2
O
1:O
4)potassium(I)], [K2(C4H2O4)(C10H6O8)(H2O)2]
n
or [K2(fum)(H4btec)(H2O)2]
n
, (1), and poly[aqua(μ8-2,5-dicarboxybenzene-1,4-dicarboxylato-κ12
O
1:O
1′,O
2:O
2,O
2′:O
2′:O
4:O
4′,O
5:O
5,O
5′:O
5′)(μ-ethanedioato-κ4
O
1,O
2:O
1′,O
2′)strontium(II)], [Sr2(C2O4)(C10H4O8)(H2O)2]
n
or [Sr2(ox)(H2btec)(H2O)2]
n
, (2) (H4btec = benzene-1,2,4,5-tetracarboxylic acid, H2btec = 2,5-dicarboxybenzene-1,4-dicarboxylate, fum = fumarate and ox = oxalate), have been obtained under hydrothermal conditions by reacting the different alkali and alkaline earth metal salts with H4btec, fumaric acid (H2fum) and oxalic acid (H2ox). Complexes (1) and (2) were structurally characterized by single-crystal X-ray diffraction, IR and UV–Vis spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetic analysis–differential scanning calorimetry (TGA–DSC). Complex (1) displays a two-dimensional (2D) layer with the K+ ion in a distorted pentagonal bipyramidal geometry and exhibits a uninodal 6-connected hxl/Shubnikov plane net (3,6) with {36.46.53} topology. Complex (2) displays a three-dimensional (3D) network structure, in which the Sr2+ ion is in a distorted monocapped square antiprism geometry. The framework possess a binodal (5,8)-connected net with the Schläfli symbol {32.410.58.64.74}{32.46.52}2. The 3D Hirshfeld surfaces and 2D fingerprint plots show that the main interactions are the O...H/H...O intermolecular interactions. Moreover, the thermal decompositions of (1) and (2) in the temperature range 303–1273 K revealed that they both decompose in three steps and transform to the corresponding metal oxide.
Sources of accountability inside the boardroom
Authors: Goodman Julia , Pearson Hayley , Mthombeni Morris
Published: January 2021

Purpose

Despite indications of scholarly interest, there are still gaps in the research of the concept of felt accountability, especially the felt accountability of board members. This paper aims to clarify the sources of accountability experienced by board members. Especially those in a non-executive capacity. How these sources can be accessed to enhance felt accountability and thereby governance effectiveness is explored.

Design/methodology/approach

Qualitative, exploratory research methods were used. In total, 15 semi-structured, in-depth interviews were completed with non-executive board members of Johannesburg Stock Exchange listed companies in South Africa. Thematic content analysis was used to analyse data.

Findings

The findings clarified the formal and informal sources of accountability experienced by non-executive board members. This included relational and structural mechanisms that can be used within corporate governance to enhance both types of accountability. Accessing the identified sources of accountability through appropriate mechanisms could increase the levels of felt accountability experienced by the individual non-executive board member, thereby strengthening accountability inside the boardroom and improving overall board effectiveness. The study also revealed a layer of implicit and explicit accountability.

Research limitations/implications

The study was conducted solely in South Africa, with non-executive board members of Johannesburg Stock Exchange listed companies.

Originality/value

There is limited research that clarifies the sources of accountability experienced by non-executive board members. This study aims to address this gap in the literature by providing techniques on how to enable the clarified sources of accountability to improve governance effectiveness.
Research watch: exclusion and health inequality in England and what can be done to reverse it – discussing the Marmot review 10 years on
Authors: Holttum Sue
Published: January 2021

Purpose

This paper aims to summarise key messages from a major evidence review of health inequality in England since 2010 – “the Marmot Review 10 Years on”.

Design/methodology/approach

Alongside “the Marmot Review 10 Years on”, which came out in February 2020, the author accessed the original Marmot review published in 2010, a 2020 article by Marmot, and Marmot’s online talk to the Royal Society of Physicians Edinburgh on 2nd of July 2020. The author drew out key messages from these sources.

Findings

Although many local authorities have taken up the 2010 Marmot review recommendations, they have been working against budget cuts under the system known as austerity. This has reduced funding to already deprived areas and probably explains worsened health inequality in England compared to other European countries. There are examples of successful local partnerships that have improved lives, but they rely on temporary charity funding. Health services can work for change locally, but central government policies must help. This has become even more urgent since the pandemic.

Originality/value

The original Marmot review and “the Marmot Review 10 Years on” are major evidence-based examinations of what causes and maintains health inequality, both physical and mental, and how this situation might be improved. It is impossible to study them and still believe that health is just about lifestyle choices. People need real options to choose from, and this is only possible if they live in places designed for human thriving from childhood to old age. As a nation, England can move towards this goal rather than further away from it. These reports show the way.
Optimal vacuum erectile device therapy regimen for penile rehabilitation in a bilateral cavernous nerve crush rat model
Authors: Ma Ming , Qin Feng , Wu Changjing , Xiong Wenfeng , Yu Botao , Wei Shanzun , Huang Chunxu , Xu Jianrong , Yang Xinzong , Yuan Jiuhong
Published: January 2021

Background

Vacuum erectile device (VED) therapy has been widely used in penile rehabilitation after radical prostatectomy; however, there is no consensus on the best regimen.

Objectives

To explore an optimal VED therapy regimen in bilateral cavernous nerve crush (BCNC) rat model.

Materials and Methods

Adult male rats were used to measure the effects of different durations (1–30 min) of VED treatment on penile length, penile blood gas analysis, and adverse effects. Forty‐eight adult male rats were randomly divided into Sham, BCNC, and VED treatment groups (2–3–2–3 min, 4–3–3 min, 5–5 min, and 10 min). Penile length, erectile function, and side effects were detected after VED treatment. Histopathological staining and Western blotting were performed to explore the cellular and molecular changes.

Results

Prolongation of the duration of VED treatment significantly decreased the penile oxygen saturation, partial oxygen pressure, and arterial blood ratio (P < 0.05). Compared with the BCNC group, all VED treatment regimens partially reversed BCNC‐induced penile shortening and erectile dysfunction (P < 0.0001), with the 4–3–3‐min and 5–5‐min treatment groups exhibiting more significant improvement than the 10‐min and 2–3–2–3‐min treatment groups (P < 0.0001). The mechanism may be related to the up‐regulation of the smooth muscle cell/collagen ratio, endothelial nitric oxide synthase, and α‐smooth muscle actin (all P < 0.0001); and the down‐regulation of hypoxia‐inducible factor‐1α, transforming growth factor‐β1, and apoptosis (all P < 0.0001). The incidence of adverse effects in the 2–3–2–3‐min treatment group was the highest.

Discussion

The commonly used VED therapy regimens maintained erectile function and penile length of BCNC rat by relieving hypoxia and fibrosis, and no further benefits were observed with increased treatment frequency or prolonged treatment duration.

Conclusion

Two consecutive 5‐min treatments with a short interval is the optimal VED therapy regimen for penile rehabilitation in BCNC rat model.
Behavioural response of the fungus gnat, Bradysia impatiens (Diptera: Sciaridae) towards certain edible mushrooms and saprophytic fungi
Authors: Xi Lulu , Zhou Xiang , Liu Yinquan , Li You , Shi Haojie , Wu Hong , Huang Junhao
Published: January 2021

The fungus gnat Bradysia impatiens (Johannsen) is a worldwide pest inhabiting organic‐rich environments, including mushroom‐cultivation substrates, which leads to massive production losses of edible mushrooms. To promote a non‐insecticidal pest control strategy, we evaluated adult behavioural response towards two saprophytic fungal strains Aspergillus flavus Link and Mucor circinelloides Tiegh., isolated from B. impatiens‐inhabiting substrates and six edible mushrooms species. Our results indicated that (a) B. impatiens was most attracted to the oyster mushroom Pleurotus ostreatus among all six edible mushrooms; (b) males and females demonstrated a significant attraction for M. circinelloides over A. flavus and P. ostreatus; (c) adults demonstrated dynamic attraction tendencies that varied with the culture periods of A. flavus and M. circinelloides, wherein females represented most (mean = 78.6%) of the attracted individuals; and (d) larvae that fed on mycelial cultures of M. circinelloides could complete their entire life cycles, but larvae could not survive on a non‐fungal or A. flavus diet. These results demonstrate the potential for the development of M. circinelloides in a push‐pull strategy to biocontrol this pest in edible mushroom cultivation.
Characterizing Longitudinal Changes in Physical Activity and Fear of Falling after Falls in Glaucoma
Authors: E Jian‐Yu , Mihailovic Aleksandra , Schrack Jennifer A. , Li Tianjing , Friedman David S. , West Sheila K. , Gitlin Laura N. , Ramulu Pradeep Y.
Published: January 2021

Background

Older adults with visual impairments experience a higher risk of falling, and are more vulnerable to adverse health consequences associated with falls than those with normal vision. This study characterizes longitudinal changes in objectively measured physical activity and fear of falling (FoF) occurring after various types of falls in visually impaired older adults.

Design

Prospective cohort study.

Setting

Hospital‐based enrollment.

Participants

People with glaucoma or suspected glaucoma.

Measurements

Falls were defined as unintentionally coming to rest on the ground or a lower level, and injurious falls were determined though follow‐up calls. Study participants were categorized into three groups–fallers with injurious consequences, fallers without injurious consequences, and non‐fallers based on fall status in the first year. Physical activity was assessed by waist‐bound accelerometer. FoF was evaluated by questionnaire, with Rasch modeling generating FoF scores where higher scores reflected worse FoF. The 3‐year longitudinal changes of physical activity and FoF were modeled using mixed‐effects models.

Results

In linear models fully adjusted for visual field damage and other covariates, physical activity among injurious fallers showed greater annual (per year) declines in daily steps (−425 steps/d, 95% confidence interval (CI) = −793, −57), daily active minutes (−13 min/d, 95% CI = −21, −6), and daily moderate and vigorous physical activity (MVPA) minutes (−3 MVPA minutes/d, 95% CI = −5, 0) over the 3‐year period as compared to non‐fallers; however, physical activity did not significantly decline among non‐injurious fallers. No longitudinal increases in FoF scores were observed in injurious or non‐injurious fallers when compared to non‐fallers.

Conclusion

Among visually impaired older adults, injurious falls identified prospectively over 12 months contributed to a significant decline in physical activity over a 3‐year period, while minimal changes were observed in FoF.
COVID‐19: Neuroimaging Features of a Pandemic
Authors: Ladopoulos Theodoros , Zand Ramin , Shahjouei Shima , Chang Jason J. , Motte Jeremias , Charles James Jeyanthan , Katsanos Aristeidis H. , Kerro Ali , Farahmand Ghasem , Vaghefi Far Alaleh , Rahimian Nasrin , Ebrahimzadeh Seyed Amir , Abedi Vida , Papathanasiou Matilda , Labedi Adnan , Schneider Ruth , Lukas Carsten , Tsiodras Sotirios , Tsivgoulis Georgios , Krogias Christos
Published: January 2021

BACKGROUND AND PURPOSE

The ongoing Coronavirus Disease 2019 (COVID‐19) pandemic is caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). COVID‐19 is occasionally associated with manifold diseases of the central nervous system (CNS). We sought to present the neuroimaging features of such CNS involvement. In addition, we sought to identify typical neuroimaging patterns that could indicate possible COVID‐19‐associated neurological manifestations.

METHODS

In this systematic literature review, typical neuroimaging features of cerebrovascular diseases and inflammatory processes associated with COVID‐19 were analyzed. Reports presenting individual patient data were included in further quantitative analysis with descriptive statistics.

RESULTS

We identified 115 studies reporting a total of 954 COVID‐19 patients with associated neurological manifestations and neuroimaging alterations. A total of 95 (82.6%) of the identified studies were single case reports or case series, whereas 660 (69.2%) of the reported cases included individual information and were thus included in descriptive statistical analysis. Ischemia with neuroimaging patterns of large vessel occlusion event was revealed in 59.9% of ischemic stroke patients, whereas 69.2% of patients with intracerebral hemorrhage exhibited bleeding in a location that was not associated with hypertension. Callosal and/or juxtacortical location was identified in 58.7% of cerebral microbleed positive images. Features of hemorrhagic necrotizing encephalitis were detected in 28.8% of patients with meningo‐/encephalitis.

CONCLUSIONS

Manifold CNS involvement is increasingly reported in COVID‐19 patients. Typical and atypical neuroimaging features have been observed in some disease entities, so that familiarity with these imaging patterns appears reasonable and may assist clinicians in the differential diagnosis of COVID‐19 CNS manifestations.
Performance of a Direct Bonded Sub-Millimeter Peek Coating for Hydrodynamic Plain Bearings
Authors: Weißbacher Christoph , Kiefel Angelika , Blumenthal Hardwig , Marheineke Jonas , Piton Sebastien
Published: January 2021

Despite their superior tribological properties, thick-layer bearing coatings based on polyetheretherketone (PEEK) have up to now not been applied in a very high number of plain bearings for industrial applications. This can at least partly be credited to the high costs and low flexibility associated with the coating process for these materials. At the same time, while thick-layer polytetrafluoroethylene (PTFE) coatings have been successfully applied in industrial plain bearings for around 50 years, thin-layer PTFE coatings today constitute the majority of applications of PTFE in plain bearings. It is therefore reasonable to assume a similar approach for thin-layer PEEK coatings. This article reports the performance of a thin-layer PEEK coating directly applied on a mild steel substrate, with results ranging from first sample test through component tests to application in an actual machine and behavior during realistic operating conditions and induced bearing failure.
Experimental and Numerical Study of Air Vessel in Quasi-Two-Dimensional Transient Flow Analysis
Authors: Kim Hyunjun , Choi Lakwon , Kim Sanghyun
Published: January 2021

An air vessel is a simple and effective device for protecting a pipeline system from abnormal pressure events. In order to design and select a suitable air vessel, analysis of the pipeline system is necessary. A quasi-2D approach can overcome some of the limitations of the conventional one-dimensional transient flow analysis method. However, only a few hydraulic components can be implemented in the quasi-2D approach. In this study, we propose a methodology for applying an air vessel in the quasi-2D model. An experimental study is performed for validating the proposed model. Although an identical approach involving an accumulator model is used to model the air vessel as in the 1D model, the quasi-2D model shows improved performance for the experimental system.
Excitation of Shear Layer Due to Surface Roughness Near the Leading Edge: An Experiment
Authors: Singh Pradeep , Sarkar S.
Published: January 2021

In this paper, a comprehensive study has been performed to address the excitation of a separated boundary layer near the leading edge due to surface roughness. Experiments are performed on a model airfoil with the semicircular leading edge at a Reynolds number (Rec) of 1.6×105, where the freestream turbulence (fst) is 1.2%. The flow features are investigated over the three rough surfaces with the roughness characteristic in the wall unit of 17, 10.5, and 8.4, which are estimated from the velocity profile at a location far downstream of reattachment. The wall roughness results in an early transition and reattachment, leading to a reduction of the laminar shear layer length apart from the bubble length. It is worthwhile to note that although the large-amplitude pretransitional perturbations are apparent from the beginning for the rough surface, the shear layer reflects the amplification of selected frequencies, where the fundamental frequency when normalized is almost the same as that of the smooth wall. The universal intermittency curve can be used to describe the transition of the shear layer, which exhibits some resemblance to the excitation of the boundary layer under fst, signifying the viscous effect.
Numerical Investigation of Nanoparticles Shape Impacts on Thermal Energy Transfer and Flow Features of Nanofluid Impingement Jets
Authors: Shirvani Behrang Asghari , Sodagar Javad , Eynijengheshlaghi Farshid , Arabkoohsar Ahmad
Published: January 2021

Today, energy transfer enhancement techniques have received much attention for design and manufacturing more efficient systems in various industries such as automotive, computers, electronics, and so forth. One way to achieve high-efficiency cooling systems is to use impingement jet cooling. In the present study, a numerical study has been conducted on nanofluid impingement jet in the vertical position to investigate the fluid flow characteristics and thermal energy transfer features. The working fluid in this study is a nanofluid with water–ethylene glycol mixture as base fluid and nanoparticles of boehmite alumina. The flow is considered to be laminar, steady-state, two-dimensional, symmetrically axial, for which the finite volume method is used to solve the equations. The effect of the Reynolds number variations, the volume fraction of nanoparticle, and different nanoparticle shapes (including spherical, plate, blade, cylindrical, and brick shapes) on thermophysical features of the flow are studied. The results reveal that the increasing Reynolds number and the increasing volume fraction of nanoparticles improves the thermal energy transfer rate. The highest Nusselt number leads to a maximum of energy transfer related to nanofluids with platelet and cylindrical nanoparticles, while the lowest thermal energy transfer rate is related to nanofluids containing spherical nanoparticles. Moreover, it is illustrated that nanofluids with platelets nanoparticles, because of their higher effective viscosity compares to other nanofluids, experience the highest pressure drop and those of with spherical nanoparticles show the lowest pressure drop.
An Approach to Bayesian Optimization for Design Feasibility Check on Discontinuous Black-Box Functions
Authors: Biswas Arpan , Hoyle Christopher
Published: January 2021

The paper presents a novel approach to applying Bayesian Optimization (BO) in predicting an unknown constraint boundary, also representing the discontinuity of an unknown function, for a feasibility check on the design space, thereby representing a classification tool to discern between a feasible and infeasible region. Bayesian optimization is a low-cost black-box global optimization tool in the Sequential Design Methods where one learns and updates knowledge from prior evaluated designs, and proceeds to the selection of new designs for future evaluation. However, BO is best suited to problems with the assumption of a continuous objective function and does not guarantee true convergence when having a discontinuous design space. This is because of the insufficient knowledge of the BO about the nature of the discontinuity of the unknown true function. In this paper, we have proposed to predict the location of the discontinuity using a BO algorithm on an artificially projected continuous design space from the original discontinuous design space. The proposed approach has been implemented in a thin tube design with the risk of creep-fatigue failure under constant loading of temperature and pressure. The stated risk depends on the location of the designs in terms of safe and unsafe regions, where the discontinuities lie at the transition between those regions; therefore, the discontinuity has also been treated as an unknown creep-fatigue failure constraint. The proposed BO algorithm has been trained to maximize sampling toward the unknown transition region, to act as a high accuracy classifier between safe and unsafe designs with minimal training cost. The converged solution has been validated for different design parameters with classification error rate and function evaluations at an average of <1% and ∼150, respectively. Finally, the performance of our proposed approach in terms of training cost and classification accuracy of thin tube design is shown to be better than the existing machine learning (ML) algorithms such as Support Vector Machine (SVM), Random Forest (RF), and Boosting.
Parametric Study on the Performance of Combined Power Plant of Steam and Gas Turbines
Authors: Almajali M. R. , Quran Omar A. S.
Published: January 2021

This paper deals with aspects of the combined power and power (CPP) plants. Such plants consist of two major parts: the steam turbine and gas turbine plants. This study investigates the efficiency of CPP under the effect of several factors. CPP plants including an open cycle gas turbine and a bottoming cycle steam turbine can achieve the highest thermal efficiency obtained with turbomachinery up to date. In this cycle, the anticipated waste thermal energy of the exhaust of gas turbine is used to generate high-pressure steam to empower the steam turbine in the steam cycle. By systematically varying the main design parameters, their influence on the CPP plant can be revealed. A comprehensive parametric study was conducted to measure the influence of the main parameter of the gas and steam cycles on the performance of CPP. The results exhibit that the overall plant thermal efficiency is significantly greater than that of either of the two turbines. Due to the high thermal efficiency, a significant reduction in the greenhouse effect can be achieved. It is found that the regenerative steam cycle will reduce the overall efficiency of the combined cycle. On the other hand, using the reheat steam cycle in the CPP plant will lead to an increase in both the thermal efficiency of the plant and the dryness factor of steam at the exit of the steam turbine.