bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical simulation of bubbly flow around a cylinder by semi-Lagrangian–Lagrangian method
Authors: Nguyen Van Luc , Degawa Tomohiro , Uchiyama Tomomi , Takamure Kotaro
Published: September 2019

Purpose

The purpose of this study is to design numerical simulations of bubbly flow around a cylinder to better understand the characteristics of flow around a rigid obstacle.

Design/methodology/approach

The bubbly flow around a circular cylinder was numerically simulated using a semi-Lagrangian–Lagrangian method composed of a vortex-in-cell method for the liquid phase and a Lagrangian description of the gas phase. Additionally, a penalization method was applied to account for the cylinder inside the flow. The slip condition of the bubbles on the cylinder’s surface was enforced, and the outflow conditions were applied to the liquid flow at the far field.

Findings

The simulation clarified the characteristics of a bubbly flow around a circular cylinder. The bubbles were shown to move around and separate from both sides of the cylinder, because of entrainment by the liquid shear layers. Once the bubbly flow fully developed, the bubbles distributed into groups and were dispersed downstream of the cylinder. A three-dimensional vortex structure of various scales was also shown to form downstream, whereas a quasi-stable two-dimensional vortex structure was observed upstream. Overall, the proposed method captured the characteristics of a bubbly flow around a cylinder well.

Originality/value

A semi-Lagrangian–Lagrangian approach was applied to simulate a bubbly flow around a circular cylinder. The simulations provided the detail features of these flow phenomena.
Numerical investigation of heat transfer of laminar and turbulent pulsating Al2O3/water nanofluid flow
Authors: Hoseinzadeh S. , Heyns P.S. , Kariman H.
Published: September 2019

Purpose

The purpose of this paper is to investigate the heat transfer of laminar and turbulent pulsating Al203/water nanofluid flow in a two-dimensional channel. In the laminar flow range, with increasing Reynolds number (Re), the velocity gradient is increased. Also, the Nusselt number (Nu) is increased, which causes increase in the overall heat transfer rate. Additionally, in the change of flow regime from laminar to turbulent, average thermal flux and pulsation range are increased. Also, the effect of different percentage of Al2O3/water nanofluid is investigated. The results show that the addition of nanofluids improve thermal performance in channel, but the using of nanofluid causes a pressure drop in the channel.

Design/methodology/approach

The pulsatile flow and heat transfer in a two-dimensional channel were investigated.

Findings

The numerical results show that the Al2O3/Water nanofluid has a significant effect on the thermal properties of the different flows (laminar and turbulent) and the average thermal flux and pulsation ranges are increased in the change of flow regime from laminar to turbulent. Also, the addition of nanofluid improves thermal performance in channels.

Originality/value

The originality of this work lies in proposing a numerical analysis of heat transfer of pulsating Al2O3/Water nanofluid flow -with different percentages- in the two-dimensional channel while the flow regime change from laminar to turbulent.
Abrasive wear analysis of RZ5/TiC in-situ composites: a statistical approach
Authors: Mehra Deepak , Mahapatra Manas Mohan , Harsha Suraj Prakash
Published: September 2019

Purpose

The RZ5 mg alloy is used in automotive and aerospace applications including helicopter gearboxes and aircraft components. These components are prone to the wear as per the demands. The present work is the study of the significance of hard particle/ceramic, i.e. titanium carbide (TiC) in RZ5 mg alloy to protect the machine components from wear.

Design/methodology/approach

The abrasive wear analysis of in-situ RZ5-TiC magnesium matrix composite is considered for the study. The primary focus of the present work is to analyze the effects of varying control parameters, i.e. Wt.% of TiC, sliding distance and applied load on the responses, i.e. weight loss and coefficient of friction. Full factorial design of the experiment based on statistical analysis is used.

Findings

It is observed that the individually Wt.% of TiC and sliding distance show the comparatively significant effect on both responses. Similarly, the interaction between sliding distance and Wt.% of TiC indicated the considerable impact on weight loss. The regression equations are developed and validated for estimating responses. It is observed that the percentage errors are not appearing more than 10 per cent of responses. Therefore, the close agreement between measured and predicted values shows the adequacy of the model. The control factor is optimized using multi-response optimization. The variations of the order of 2.47 and 2.35 per cent in target value of the coefficient of friction and weight loss are achieved.

Originality/value

The current manuscript provides a detailed abrasive wear statistical analysis of RZ5-TiC composite. The influence of control parameters on the responses using the full factorial design, the main effect plots and interaction effects are presented.
The tribological performance of engineered micro-surface topography by picosecond laser on PEEK
Authors: Wang Meiling
Published: September 2019

Purpose

The purpose of this study is to investigate the effect of engineered micro-structures on the tribological properties of metal-polyetheretherketone (PEEK) surface.

Design/methodology/approach

Circular dimples with diameters of 25 and 50 µm were designed and manufactured on PEEK plate specimens using picosecond laser. Reciprocating friction and wear tests on a ball-on-flat configuration were performed to evaluate the tribological properties of the designed micro-structures in dry contacts. The loading forces of 0.9 and 3 N were applied.

Findings

As a result, obvious fluctuations of coefficient of friction curve were observed in tribosystems consisting of non-textured and textured PEEK with circular dimples of 25 µm in diameter. GCr15 ball/textured PEEK plate specimens with circular dimples of 50 µm in diameter revealed a superior friction and wear property.

Originality/value

Different to the existing studies in which the tribopairs consist of hard bearing couples, this study investigated the tribological properties of the engineered micro-structures on the hard-on-soft bearing couples.
Development of e-tendering evaluation system for Nigerian public sector
Authors: Abdullahi Bello , Ibrahim Yahaya Makarfi , Ibrahim Ahmed , Bala Kabir
Published: September 2019

Purpose

The revolution brought about by the internet and the World Wide Web has led to the development of numerous e-Tendering systems for public sector tendering that have automated various aspects of the manual tendering processes that are known to experience numerous problems. However, one key area that has not been fully addressed is the automation of the evaluation of public tenders based on group decision-making. This paper presents part of the development of a Web-based e-tendering system called Nigerian Public Sector eTender (NPS-eTender) that automate the evaluation of public sector tenders based on group decision-making.

Design/methodology/approach

The system was developed using object-oriented methodologies. Specifically, Ripple and unified process methodologies were adopted.

Findings

The results of the system validation showed that NPS-eTender has an average rating of 74% with respect to correct and accurate modelling of the existing tendering domain and an average rating of 67.6% with respect to its potential to enhance the proficiency of public sector tendering in Nigeria. Based on the results of the validation, it can be concluded that the automation of the tender evaluation process can lead to a more proficient tendering process.

Originality/value

This research has contributed to the development of an e-Tendering system for the public sector that supports the whole tendering lifecycle including the automation of evaluation of public tenders based on group decision-making.
Measures to improve the adoption of life cycle assessment in the South African construction industry
Authors: Kwofie Titus Ebenezer , Aigbavboa Clinton Ohis , Thwala Wellington Didibhuku
Published: September 2019

Purpose

In spite of the urge among stakeholders to increase sustainability in the built environment, the South African Construction Industry (SACI) continues to suffer from low level of adoption of strategies such as life cycle assessment (LCA) to increase sustainable building practices in building and infrastructure delivery, hence the need to increase the adoption of sustainable concepts and sustainability practices is an emergent necessity. This study aims to identify the measures that can increase the adoption of LCA toward overcoming the practical difficulties, theoretical concerns and structural differences encountered in making gains in achieving sustainable practices in the SA construction industry.

Design/methodology/approach

The study adopted a deductive research design using a questionnaire survey with mean scores, Kruskal–Wallis and least square regression analysis done.

Findings

The study determined ten measures that can significantly influence about 88 per cent improvement in the success of LCA adopting in the SA industry. Also, there was a higher level of consensus in the findings which offers credence and good representation of the practical reality in the LCA adoption in South Africa.

Originality/value

These measures could be seen to embrace behavioural, social, technical and policy dimensions of LCA adoption. The findings are thus crucial in overcoming challenges to LCA methodologies in achieving sustainable building practices in the construction process in building and infrastructural delivery in SACI.
Strategies for health and safety management in Ghana
Authors: Simpson Kweku Bedu , Sam Aloysius
Published: September 2019

Purpose

This paper aims to investigate the contemporary strategies for Health and Safety (H&S) management practices at the construction sites in Ghana.

Design/methodology/approach

The study used a mixed method approach in conducting a cross-sectional survey at 28 active construction sites in the Kumasi and Accra metropolises of Ghana using questionnaires and interview guide by using purposive, convenience and snowball sampling techniques. Data were collected from 170 survey respondents and 18 interview participants comprising artisans and management staff.

Findings

On H&S management practices, the study found that most construction sites have policies for H&S delivery and are duly followed and enforced. Nonetheless, construction workers moderately agreed that there was reward for; the avoidance and reduction of accidents and illnesses, good H&S behaviour and provision for insurance and hospital claims. It was also revealed that most of the construction sites adopt either one or a combination of mandatory H&S standards. Generally, most workers possessed a fairly positive perception about the H&S management practices at their sites and were either satisfied or very satisfied with its performance.

Research limitations/implications

Generalizing the findings beyond the study areas is limited because of the use of the non-probability sampling techniques.

Originality/value

This study focused on the active construction sites in the study areas to investigate their H&S practices against the backdrop of numerous publications describing the general H&S situation in Ghana as poor. It revealed the current H&S performance of the construction sites for the benefit of the construction industry, researchers and the academia.
Talent retention in Indian public sector units (PSUs): an empirical investigation
Authors: Mukherjee Bidhan , Chandra Bibhas , Singh Saumya
Published: September 2019

Purpose

In response to scholarly calls, this study aims to explore the persuasive predictors including (job security, autonomy, work-life balance, culture and climate, career growth, leadership style and support, training and development and reward, recognition and pay) of talent retention in Indian PSUs by emphasising the commonalities and differences between different category of employees from different cohorts based on their contribution in the prime function of the business.

Design/methodology/approach

A self-administered questionnaire was used to collect data from 472 employees from selected organisations through Multistage sampling technique and Simple random sampling technique. Data were analysed using tests such as logistic regression, MANOVA,post hocTukey in SPSS 20.

Findings

Job security, autonomy, career growth and culture and climate are the persuasive predictors of talent retention in Indian PSUs. However, there is a significant interaction effect of age and job standard on job security. Job security and perceived employability do not relate to age for core category employees rather possess identical perception than other employee category. Findings indicate that identifying the position to be retained is more viable than a common retention strategy.

Originality/value

This study contributes to the existing knowledge of talent retention by exploring novel insights in comprehending the commonalities and differences of different employee category at all level from different cohorts, sharing different responsibilities in the prime function of the business that has largely been ignored. The study can succour in improving performance and cost-effective retention strategy.
Assessing the state of lean and six sigma practices in healthcare in Mexico
Authors: Peimbert-García Rodrigo E. , Matis Timothy , Beltran-Godoy Jaime H. , Garay-Rondero Claudia L. , Vicencio-Ortiz Julio C. , López-Soto Diana
Published: September 2019

Purpose

The purpose of this study is to assess the state at which lean and six sigma (LSS) are used as a management system to improve the national health system national health system of Mexico.

Design/methodology/approach

Cross-sectional survey-research. The survey was administered at 30 different hospitals across six states in Mexico. These were selected using convenience sampling and participants (N = 258) were selected through random/snowball sampling procedures, including from top managers down to front-line staff.

Findings

Only 16 per cent of respondents reported participation in LSS projects. Still, these implementations are limited to using isolated tools, mainly 5s, failure mode and effects analysis (FMEA) and Fishbone diagram, with the lack of training/knowledge and financial resources as the top disabling factors. Overall, LSS has not become systematic in daily management and operations.

Research limitations/implications

The sampling procedure was by convenience; however, every attempt was made to ensure a lack of bias in the individual responses. If still there was a bias, it is conjectured that this would likely be in overestimating the penetration of LSS.

Practical implications

The penetration of LSS management practices into the Mexican health system is in its infancy, and the sustainability of current projects is jeopardized given the lack of systematic integration. Hence, LSS should be better spread and communicated across healthcare organizations in Mexico.

Originality/value

This is the first research work that evaluates the use of LSS management practices in a Latin American country, and the first journal paper that focuses on LSS in healthcare in Mexico.
Development and validation of the willingness to intervene in bullying scale
Authors: Chen Li‐Ming , Jin Kuan‐Yu
Published: September 2019

Background

Most bullying incidents occur in the presence of bystanders, with few choosing to intervene. Therefore, the development of a valid instrument to measure individuals’ willingness to intervene in bullying is warranted.

Aims

This study aimed to develop as well as validate a self‐reported willingness to intervene in bullying scale (WIBS) for secondary school students.

Samples

Two junior high school students’ samples (N = 553; N = 950) in Taiwan were collected for both scale revision and scale validation.

Methods

This study examined whether ‘perceived severity of bullying’ and ‘self‐efficacy of intervention’ were important attributes of the willingness to intervene in bullying. The partial credit model (PCM) and the model with internal restriction of item difficulty (MIRID) were utilized to fit the data.

Results

The WIBS had good model–data fit with both the PCM and the MIRID, and it suggested (via the MIRID) that ‘perceived severity of bullying’ and ‘self‐efficacy of intervention’ are important components of the willingness to intervene in bullying scenarios, although the latter component had greater weight than did the former. Moreover, the willingness to intervene was related to the pro‐victim attitude and self‐reported defending behaviours.

Conclusions

Students’ willingness to intervene in school bullying situations could be explained by their self‐efficacy in stopping bullying and their perceived severity of bullying incidents. Therefore, educators and researchers should attempt to raise students’ self‐efficacy regarding intervention and their perceived severity of all kinds of bullying to promote their willingness to intervene in school bullying situations.
Fighting the flinch: Experimentally induced compassion makes a difference in health care providers
Authors: Reynolds Lisa M. , Powell Philip , Lin Yee Sing , Ravi Kripa , Chung Chia‐Yun Karen , Consedine Nathan S.
Published: September 2019

Objectives

Although health care providers are required to sustain care in difficult circumstances, some patients challenge this principle. Evoking compassion seems likely to be helpful in such situations. This research aimed to evaluate whether inducing compassion in health care providers might mitigate disengagement with patients who have challenging presenting features such as those with disgusting symptoms and/or are to blame for their own health problems.

Design

An online experimental study with clinical health care providers.

Methods

Medical students (n = 219) and qualified health care professionals (n = 108) took part in an online experiment. Participants were randomized to view a slideshow of either neutral images (control) or compassion‐inducing images (compassion condition) and were then presented with a series of patient vignettes where presenting problems systematically varied on patient responsibility and disgusting symptoms. Engagement was assessed by asking participants how caring they felt, how much they would want to help, how challenging it would be, and whether they would wear a mask.

Results

Participants reported less engagement with patients who were responsible for their illness and who presented with disgusting symptoms. Induced compassion offset disengagement and qualified health professionals were more caring and willing to help patients than medical students. The compassion induction eliminated some differences between experienced and trainee clinicians.

Conclusions

This research demonstrates that disgust and patient responsibility impacts clinical engagement and that medical students are more impacted by such scenarios than qualified health providers. Inducing compassion may help to mitigate these differences, and further investigation into strategies that foster engagement with difficult patients is warranted.

Statement of contribution

What is already known on the subject?

Health care providers are required to sustain care across all patients; however, some patients are more difficult to engage with than others.

Clinical engagement appears to be impacted when patients present with disgusting symptoms and/or are to blame for their own health problems.

What does this study add?

This work reports on a vignette‐based study that shows that disgusting symptoms and patient responsibility impact self‐reported measures of clinical engagement in response to patient scenarios.

Qualified health care providers are less likely to disengage in these situations than medical students.

A very brief online induction of compassion has potential to mitigate differences between trained professionals and students.
Low rate of local recurrence detection by rectoscopy in follow‐up of rectal cancer
Authors: Tronstad P.K. , Simpson L.V. Hume , Olsen B. , Pfeffer F. , Karliczek A.
Published: September 2019

Aim

The main aim of this study was to examine the effectiveness of rectoscopy for detecting local recurrence of rectal cancer in patients following low anterior resection.

Method

This was a retrospective study of 201 patients, who underwent low anterior resection for rectal or rectosigmoid cancer between 2007 and 2009 and who were followed up with rigid rectoscopy and imaging. A total of 91 patients were excluded from the analysis for various reasons, leaving 110 patients eligible for analysis.

Results

A total of 613 rectoscopies were performed, and 48 biopsies taken. Six local recurrences were detected in the 110 patients, three of which were first detected by rectoscopy and three by CT. Two of the local recurrences were detected outside the follow‐up programme because of symptoms: one by rectoscopy and one by CT. Three of 613 (0.5%) rectoscopies led to detection of local recurrence. The sensitivity and specificity of rectoscopy to detect local recurrence was 0.50 and 0.93, respectively. Nineteen distant metastases were detected, and two patients had both local recurrence and distant metastasis. All local recurrences and distant metastases were detected within 48 months of surgery.

Conclusion

Rigid rectoscopy is poor at detecting local recurrence. Only 3 out of 613 rectoscopies (0.5%) detected local recurrence. Due to extramural growth of some recurrences, the sensitivity is also very low. Based on our results, routine rectoscopy in the surveillance of asymptomatic patients cannot be recommended.
Left atrial structure and function predictors of recurrent fibrillation after catheter ablation: a systematic review and meta‐analysis
Authors: Bajraktari Gani , Bytyçi Ibadete , Henein Michael Y.
Published: September 2019

Background

Catheter ablation (CA) has become a conventional treatment for atrial fibrillation (AF), but remains with high recurrence rate. The aim of this meta‐analysis was to determine left atrial (LA) structure and function indices that predict recurrence of AF.

Methods

We systematically searched PubMed‐Medline, EMBASE, Scopus, Google Scholar and the Cochrane Central Registry, up to September 2017 in order to select clinical trials and observational studies which reported echocardiographic predictors of AF recurrence after CA. Eighty‐five articles with a total of 16 126 patients were finally included.

Results

The pooled analysis showed that after a follow‐up period of 21 ± 12 months, patients with AF recurrence had larger LA diameter with weighted mean difference (WMD: 2·99 ([95% CI 2·50–3·47], P<0·001), larger LA volume index (LAVI) maximal and LAVI minimal (P<0·0001 for both), larger LA area (P<0·0001), lower LA strain (P<0·0001) and lower LA total emptying fraction (LA EF) (P<0·0001) compared with those without AF recurrence. The most powerful LA predictors (in accuracy order) of AF recurrence were as follows: LA strain <19% (OR: 3·1[95% CI, –1.3‐10·4], P<0·0001), followed by LA diameter ≥50 mm (OR: 2·75, [95% CI 1·66–4·56,] P<0·0001), and LAVmax >150 ml (OR: 2·25, [95% CI, 1.1–5·6], P = 0·0002).

Conclusions

Based on this meta‐analysis results, a dilated left atrium with diameter more than 50 mm and volume above 150 ml or myocardial strain below 19% reflect an unstable LA that is unlikely to hold sinus rhythm after catheter ablation for atrial fibrillation.
Endocan as a marker of disease severity in pulmonary thromboembolism
Authors: Kuluöztürk Mutlu , İn Erdal , İlhan Nevin
Published: September 2019

Introduction

The aim of this study is to determine the serum endocan levels in patients with pulmonary thromboembolism (PTE) and investigate whether a relationship exists between serum endocan levels and the disease severity.

Materials and Methods

The study included 85 patients with acute PTE and 40 healthy control subjects. The patients with PTE were divided into three groups at admission as “high‐risk”, “intermediate‐risk” and “low‐risk”, considering the guidelines of the European Society of Cardiology. Serum endocan levels in all participants' blood samples were measured.

Results

The mean serum endocan levels were significantly higher in the PTE group, compared to the control subjects (P < 0.001). Serum endocan levels were significantly higher in the “high‐risk” group when compared with patients in the “low‐risk” and “intermediate‐risk” groups (P < 0.001 and P < 0.01 respectively). Similarly, serum endocan levels were higher in the “intermediate‐risk” group compared to those in the “low‐risk” group (P < 0.001). There was a negative correlation between serum endocan levels and partial oxygen pressure (r = −0.262, P = 0.016), whereas a positive correlation was found between the serum endocan levels and systolic pulmonary arterial pressure (r = 0.296, P = 0.006). Additionally, endocan had an area under the curve in the receiver operating characteristic curve of 0.837 (0.768‐0.907; 95% CI; P < 0.001) and cut‐off value was 194.5 pg/mL (sensitivity 80%, specificity 72.5%).

Conclusion

Serum endocan levels were higher and related to the severity of the disease in PTE patients. Additionally, endocan could be an indicator to be used in the diagnosis of PTE and in the prediction of the disease severity.
Both hypo‐ and hyperglycaemia are associated with increased fracture risk in Japanese people with type 2 diabetes: the Fukuoka Diabetes Registry
Authors: Komorita Y. , Iwase M. , Fujii H. , Ohkuma T. , Ide H. , Yoshinari M. , Oku Y. , Nakamura U. , Kitazono T.
Published: September 2019

Aim

The impact of glycaemic control on fracture risk is controversial, which may be due to the possible presence of hypoglycaemia. The aim of this study was to separately investigate the impacts of severe hypoglycaemia and poor glycaemic control on fracture risk in people with type 2 diabetes.

Methods

Overall, 4706 Japanese participants (2755 men and 1951 postmenopausal women) with type 2 diabetes (mean age 66 years) were followed prospectively (a median of 5.3 years; follow‐up rate, 97.6%), and were stratified by severe hypoglycaemia status and glycaemic control. The primary outcome was fractures at any anatomic site.

Results

Fractures occurred in 662 participants (249 men and 413 women). The age‐ and sex‐adjusted incidence rates (expressed per 1000 person‐years) were: 71.2 (multiple episodes of severe hypoglycaemia), 43.1 (one episode), 25.2 [HbA1c < 53 mmol/mol (< 7%) without severe hypoglycaemia], 28.7 [HbA1c 53 to < 64 mmol/mol (7% to < 8%) without severe hypoglycaemia], 27.7 [HbA1c 64 to < 75 mmol/mol (8% to < 9%) without severe hypoglycaemia] and 40.5 [HbA1c ≥ 75 mmol/mol (≥ 9%) without severe hypoglycaemia]. Multivariate‐adjusted hazard ratios (95% confidence intervals) for fractures were 2.24 (1.56, 3.21) in those with multiple episodes of severe hypoglycaemia, and 1.42 (1.04, 1.95) in those with HbA1c ≥ 75 mmol/mol (≥ 9%) without severe hypoglycaemia, compared with those with HbA1c < 53 mmol/mol (< 7%) without severe hypoglycaemia.

Conclusions

Both severe hypoglycaemia and poor glycaemic control were significantly related to an increased risk of fracture in people with type 2 diabetes, although severe hypoglycaemia conferred a stronger risk.
A process‐based model supports an association between dispersal and the prevalence of species traits in tropical reef fish assemblages
Authors: Donati Giulia Francesca Azzurra , Parravicini Valeriano , Leprieur Fabien , Hagen Oskar , Gaboriau Theo , Heine Christian , Kulbicki Michel , Rolland Jonathan , Salamin Nicolas , Albouy Camille , Pellissier Loïc
Published: September 2019

Habitat dynamics interacting with species dispersal abilities could generate gradients in species diversity and prevalence of species traits when the latter are associated with species dispersal potential. Using a process‐based model of diversification constrained by a dispersal parameter, we simulated the interplay between reef habitat dynamics during the past 140 million years and dispersal, shaping lineage diversification history and assemblage composition globally. The emerging patterns from the simulations were compared to current prevalence of species traits related to dispersal for 6315 tropical reef fish species. We found a significant spatial congruence between the prevalence of simulated low dispersal values and areas with a large proportion of species characterized by small adult body size, narrow home range mobility behaviour, pelagic larval duration shorter than 21 days and diurnal activity. Species characterized by such traits were found predominantly in the Indo‐Australian Archipelago and the Caribbean Sea. Furthermore, the frequency distribution of the dispersal parameter was found to match empirical distributions for body size, PLD and home range mobility behaviour. Also, the dispersal parameter in the simulations was associated to diversification rates and resulted in trait frequency matching empirical distributions. Overall, our findings suggest that past habitat dynamics, in conjunction with dispersal processes, influenced diversification in tropical reef fishes, which may explain the present‐day geography of species traits.
A fresh look at inland fisheries and their role in food security and livelihoods
Authors: Funge‐Smith Simon , Bennett Abigail
Published: September 2019

The role of inland fisheries in livelihoods, food security and sustainable development is often overshadowed by the higher profile interest in ocean issues. Whilst inland fisheries' catch and contribution to global nutrition, food security and the economy, are less than that of marine fisheries, global‐level comparisons of fish production obscure considerable livelihood impacts in certain countries and sub‐national areas. To highlight these contributions, this paper synthesizes recent data and innovative approaches for assessing such livelihood contributions and their importance in countries with limited access to ocean resources and aquaculture. Inland fisheries are crucial for many socially, economically and nutritionally vulnerable groups of people around the world, but the challenges in monitoring inland fisheries preclude a complete understanding of the magnitude of their contributions. This situation is rapidly improving with increasing recognition of inland fisheries in development discourses, which has also encouraged research to enhance knowledge on the importance of inland fisheries. We review this work, including collated information published in a recent Food and Agriculture Organization report, to provide an up to date characterization of the state of knowledge on the role of inland fisheries.
‘Dignity and respect’: An example of service user leadership and co‐production in mental health research
Authors: Faulkner Alison , Carr Sarah , Gould Dorothy , Khisa Christine , Hafford‐Letchfield Trish , Cohen Rachel , Megele Claudia , Holley Jessica
Published: September 2019

This paper explores the methodological aspects of a user‐led study investigating mental health service user experiences of targeted violence and abuse (often called 'hate crime'). 'Keeping Control' was a 16‐month qualitative study, undertaken in the context of adult safeguarding reforms in England. By collecting data on service user concepts and experiences, the research sought to address a gap in research and practice knowledge relating to targeted violence, abuse and hostility against people with mental health problems. In this paper, we discuss the significance of the design and methodology used for this study, with a particular focus on the interviews with service users. The research was both user‐led and carried out in collaboration with practitioners and academics, a form of research co‐production. Our aim is to inform researchers, practitioners and policymakers about the value of user leadership in co‐productive research with practitioners, particularly for a highly sensitive and potentially distressing topic.
Older persons’ experiences regarding evaluation of their medication treatment—An interview study in Sweden
Authors: Holmqvist Malin , Thor Johan , Ros Axel , Johansson Linda
Published: September 2019

Background

Older persons with polypharmacy are at increased risk of harm from medications, and this issue is a global patient safety challenge. Harm may arise at all stages of medication use and may cause hospital admission, additional resource utilization and lower patient satisfaction. Older persons’ participation in their own care may increase patient safety. Their views on the evaluation of their medication treatment, and their own involvement in it, are crucial yet poorly understood.

Objectives

To identify opportunities to make the medication use process safer, we explored and described older persons’ experiences of evaluation of their medication treatment.

Design

Semi‐structured interviews were performed with 20 community‐dwelling older persons (age 75‐91 years) in Sweden. Data were analysed using inductive qualitative content analysis.

Results

These older persons reported having a responsibility to engage in their medication evaluations, although some felt unable to do so or considered themselves unconcerned. Evaluation, in their experience, was facilitated by continuity of care and an invitation to participate. However, some older persons experienced not receiving a comprehensive medication evaluation.

Discussion and conclusion

Older persons want to be actively involved in their medication evaluations, and this may represent an underutilized resource in the pursuit of patient safety. Their trust in physicians to undertake evaluations on a regular basis, although that does not necessarily occur, may cause harm. Patient safety could benefit from a co‐production approach to medication evaluations, with health‐care professionals explicitly sharing information with older persons and agreeing on responsibilities related to on‐going medication treatment.
Phase evolution of SiOC‐based ceramic nanocomposites derived from a polymethylsiloxane modified by Hf‐ and Ti‐alkoxides
Authors: Sun Jia , Wen Qing‐Bo , Li Tao , Wiehl Leonore , Fasel Claudia , Feng Yao , De Carolis Dario , Yu Zhao‐Ju , Fu Qian‐Gang , Riedel Ralf
Published: September 2019

SiOC/HfO2‐based ceramic nanocomposites with in situ formed HfO2 nanoparticles were prepared via a single‐source precursor (SSP) approach starting from a polymethylsilsesquioxane (PMS) modified by Hf‐ and Ti‐alkoxides. By varying the alkyl‐group of the employed Hf‐alkoxides, SiOC/HfO2‐based ceramic nanocomposites with different HfO2 polymorphs formed via thermal decomposition of the SSP under the same heat‐treatment conditions. Using PMS chemically modified by Hf(OnBu)4, tetragonal HfO2 phase was formed after the synthesis at 1100°C in Ar, whereas both, tetragonal and monoclinic HfO2 nanocrystals, were analyzed when replacing Hf(OnBu)4 by Hf(OiPr)4. After oxidation of the synthesized nanocomposites in air at 1500°C, a facile formation of oxidation‐resistant HfSiO4 (hafnon) phase occurred by the reaction of HfO2 nanocrystals with silica present in the SiOC nanocomposite matrix derived from Hf(OiPr)4‐modified SSPs. Moreover the amount of hafnon is dramatically increased by the additional modification of the polysiloxane with Ti‐alkoxides. In contrast, ceramic nanocomposites derived from Hf(OnBu)4‐modified SSPs, almost no HfSiO4 is detected after oxidation at 1500°C even though in the case of Ti‐alkoxide‐modified single‐source precursor.
Stage 1 hypertension defined by the 2017 ACC/AHA guideline predicts future cardiovascular events in elderly Chinese individuals
Authors: Xie Yanxia , Gao Jinyue , Guo Rongrong , Zheng Jia , Wang Yali , Dai Yue , Sun Zhaoqing , Xing Liying , Zhang Xingang , Sun Ying Xian , Zheng Liqiang
Published: September 2019

The 2017 American College of Cardiology and American Heart Association (ACC/AHA) hypertension guideline updated stage 1 hypertension defined as systolic blood pressure (SBP) of 130‐139 mm Hg or diastolic blood pressure (DBP) of 80‐89 mm Hg. However, the impact of 1 hypertension that affects future cardiovascular risk remains unclear among older adults in rural China. The prospective cohort study included 7503 adults aged ≥60 years with complete data and no cardiovascular disease (CVD) at baseline. Follow‐up for the new adverse events was conducted from the end of the baseline survey to the end of the third follow‐up survey (2007.01‐2017.12). Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for blood pressure (BP) classifications and adverse events with normal BP as reference (< 120/80 mm Hg). During the 57 290 person‐years follow‐up period, 2261 all‐cause mortality, 1271 CVD mortality, 1159 stroke, and 347 myocardial infarctions (MI) occurred. Patients with stage 1 hypertension versus normal BP had HRs (95% CI) of 1.068 (0.904‐1.261) for all‐cause mortality, 1.304 (1.015‐1.675) for CVD mortality, 1.449 (1.107‐1.899) for stroke, and 1.735 (1.051‐2.863) for MI, respectively. In conclusion, among adults aged ≥60 years, stage 1 hypertension revealed an increased hazard of CVD mortality, stroke, and MI, which is complementary evidence for the application of 2017 ACC/AHA hypertension guidelines in an older Chinese population. Therefore, BP control in patients with stage 1 hypertension may be beneficial to reduce the hazard of CVD in elderly Chinese individuals.
The effects of topiroxostat on vascular function in patients with hyperuricemia
Authors: Higa Shingo , Shima Daisuke , Tomitani Naoko , Fujimoto Yoko , Kario Kazuomi
Published: September 2019

Xanthine oxidoreductase (XOR) inhibitors, such as allopurinol and febuxostat, inhibit the catalysis of serum uric acid (SUA) synthesis. In doing so, they are thought to improve vascular endothelial function in patients with hyperuricemia and cardiovascular risk by reducing increases in SUA and reactive oxygen species levels. We performed a retrospective cohort study to evaluate the effects of topiroxostat, a novel XOR inhibitor, on vascular function measured by flow‐mediated dilation (FMD) on ultrasonography. In total, 23 patients with hyperuricemia were enrolled. After approximately 8 weeks, topiroxostat was associated with a significant increase in the peak percentage change in diameter (∆FMD) from 4.53% ± 2.09% to 5.54% ± 3.08% (P = .045). It also significantly reduced the SUA levels from 7.31 ± 1.43 to 5.44 ± 1.11 mg/dL (P < .001). Although further studies are needed to validate these results, it appears that topiroxostat improves vascular endothelial function in patients with hyperuricemia.
Avoiding Unnecessary Disparities in Care: Evaluating Noninvasive Prenatal Screening Performance via Whole Genome Sequencing Across Classes of Obesity
Authors: Haverty Carrie E. , Muzzey Dale
Published: September 2019

Purpose/Aim

Examine how well noninvasive prenatal screening (NIPS) performs in women across body mass index (BMI) classes.

Hypothesis

NIPS via whole genome sequencing better serves all women, regardless of BMI, compared with traditional maternal serum screening.

Significance/Background

Noninvasive Prenatal Screening (NIPS), increasingly offered as a first‐line aneuploidy screen, has superior performance compared with maternal serum screening (MSS). Fetal fraction (FF) is one of the many factors that influence the performance of NIPS. Low FF is associated with early gestational age, a compromised placenta (eg, from triploidy and certain aneuploidies), and high BMI. By far, the most common driver of low FF is high BMI. The most recent American College of Medical Genetics and Genomics statement recommends “offering aneuploidy screening other than NIPS in cases of significant obesity.” However, patients with high BMI constitute approximately25% of US pregnancies, creating a significant disparity in care based on weight.

Methods

58,639 patients who received NIPS were stratified into standard BMI classes. For each BMI group, the aggregate analytical sensitivity was calculated by summing—over the range of FF values—the product of 1) the sensitivity for a given FF and depth based on a model of whole‐genome sequencing (WGS) NIPS and 2) the BMI‐specific probability of observing a patient at that FF. Scaled sensitivities were incorporated into residual‐risk calculations to assess impact on patient results reporting.

Findings

Due to downward shifts in the FF distribution, NIPS sensitivity drops as BMI increases: non‐obese analytical sensitivity for T21 is 99.5%, whereas for class III it is 94.1%. Nevertheless, even patients with class III BMI have expected T21 sensitivity in excess of that obtainable via standard MSS (92.9%). Sensitivity for T13 and T18 was also higher across the BMI spectrum for WGS‐based NIPS relative to MSS.

Discussion

WGS‐based NIPS with high performance at low FF is a high‐quality aneuploidy screening option for all women, regardless of BMI. Providers can therefore offer the same high level of care to all patients, regardless of body habitus.
Maternal Confidence for Physiologic Birth: Instrument Development and Testing
Authors: Neerland Carrie
Published: September 2019

Introduction

Maternal confidence is associated with enhanced birth experiences through a greater sense of control, feeling more informed, and less pain during labor. A valid and reliable measure of prenatal confidence for physiologic birth for clinical use to identify areas where confidence might be enhanced has not yet been developed.

Methods

This was a multi‐phased instrument development study. Qualitative analysis from a study with 14 women who had a normal physiologic birth, along with concept analysis on maternal confidence, informed the development of a 22‐item Likert scale, the Preparation for Labor and Birth (P‐LAB) instrument. Content validity and face validity were evaluated by a panel of 10 experts including midwives, physicians, and women who had a normal physiologic birth. Psychometric testing of the instrument was performed with a sample of 206 women who were between 34 0/7 to 38 6/7 weeks’ gestation from 5 Midwestern clinics.

Results

The P‐LAB demonstrated content validity, internal consistency, stability over time, and beginning construct validity. All items had content validity index (CVI) scores greater than or equal to 0.8 and total instrument CVI of 0.95. Four subscales were identified: planned use of pain medication, trusted relationship with care provider and care environment, confidence or fear for childbirth, and support (eg, partner, provider, environment). Cronbach's coefficients alpha for the 4 extracted factors were 0.93, 0.76, 0.73, and 0.74, accordingly. Intraclass correlation (95% CI) for the total questionnaire was 0.92 (0.88 ‐ 0.94).

Discussion

Exploratory findings demonstrate that the P‐LAB instrument exhibits beginning validity and reliability in the measurement of prenatal maternal confidence for normal physiologic birth. The P‐LAB instrument is a potentially clinically useful instrument to measure maternal confidence for normal physiologic birth, however, more testing is required for continuing to establish construct validity.
Insulin‐regulated aminopeptidase inhibitor‐mediated increases in dendritic spine density are facilitated by glucose uptake
Authors: Seyer Benjamin , Diwakarla Shanti , Burns Peta , Hallberg Anders , Grӧnbladh Alfhild , Hallberg Mathias , Chai Siew Yeen
Published: September 2019

Ethyl2‐acetylamino‐7‐hydroxy‐4‐pyridin‐3‐yl‐4H‐chromene‐3‐carboxylate (HFI‐419), the benzopyran‐based inhibitor of insulin‐regulated aminopeptidase (IRAP), has previously been shown to improve spatial working and recognition memory in rodents. However, the mechanism of its cognitive‐enhancing effect remains unknown. There is a close correlation between dendritic spine density and learning in vivo and several studies suggest that increases in neuronal glucose uptake and/or alterations to the activity of matrix metalloproteinases (MMPs) may improve memory and increase dendritic spine density. We aimed to identify the potential mechanism by which HFI‐419 enhances memory by utilizing rat primary cultures of hippocampal cells. Alterations to dendritic spine density were assessed in the presence of varying concentrations of HFI‐419 at different stages of hippocampal cell development. In addition, glucose uptake and changes to spine density were assessed in the presence of indinavir, an inhibitor of the glucose transporter 4 (GLUT4), or the matrix metalloprotease inhibitor CAS 204140‐01‐2. We confirmed that inhibition of IRAP activity with HFI‐419 enhanced spatial working memory in rats, and determined that this enhancement may be driven by GLUT4‐mediated changes to dendritic spine density. We observed that IRAP inhibition increased dendritic spine density prior to peak dendritic growth in hippocampal neurons, and that spine formation was inhibited when GLUT4‐mediated glucose uptake was blocked. In addition, during the peak phase of dendritic spine growth, the effect of IRAP inhibition on enhancement of dendritic spine density resulted specifically in an increase in the proportion of mushroom/stubby‐like spines, a morphology associated with memory and learning. Moreover, these spines were deemed to be functional based on their expression of the pre‐synaptic markers vesicular glutamate transporter 1 and synapsin. Overall, or findings suggest that IRAP inhibitors may facilitate memory by increasing hippocampal dendritic spine density via a GLUT4‐mediated mechanism.

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Cover Image for this issue: doi: 10.1111/jnc.14745.
The effect of allogenic human Wharton's jelly stem cells seeded onto acellular dermal matrix in healing of rat burn wounds
Authors: Nazempour Mehra , Mehrabani Davood , Mehdinavaz‐Aghdam Rouhollah , Hashemi Seyedeh‐Sara , Derakhshanfar Amin , Zare Shahrokh , Zardosht Mitra , Moayedi Javad , Vahedi Mahjoob
Published: September 2019

Background

Various methods were introduced to overcome the autograft shortage in burn wound care, including cell transplantation and tissue engineering.

Aims

To evaluate the healing effect of allogenic human Wharton's jelly stem cells (hWJSCs) seeded onto acellular dermal matrix (ADM) in rat burn injuries.

Patients and Methods

Human Wharton's jelly stem cells provided from umbilical cord tissue were characterized before transplantation, and the growth kinetic was determined. Skin samples from cosmetic surgeries were used for preparation of ADM. Forty male Sprague Dawley rats were randomly divided into 4 equal groups. Third‐degree burn was induced for all animals by exposing to hot water using a 2 cm ring for 10 seconds. Group 1 was burned rats that did not receive any treatment. After burn injury, the second group received silver sulfadiazine (SSD), the third group was treated just by using ADM, and the fourth group received 2 × 106 hWJSCs seeded onto ADM. The animals were euthanized for histologic evaluation after 7, 14, and 21 days.

Results

Human Wharton's jelly stem cells were characterized to be spindle shape and positive for osteogenic and adipogenic induction and for mesenchymal markers but lacked hematopoietic markers. Population doubling time (PDT) was 40.1 hours with an increasing growth trend until day 6th. Macro‐ and microscopically, the healing was mild in ADM group and moderate in ADM + hWJSCs group after 21 days.

Conclusion

Allogenic hWJSCs seeded onto ADM improved the healing process in burn wounds denoting to their therapeutic and anti‐inflammatory effects in burn wounds that can be added to the literature.