bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of calcium-based grease from coconut oil methyl ester and evaluation of its tribological properties
Authors: Kizhakkeappillil Joseph Babu
Published: September 2022

Coconut oil has excellent tribological properties compared to many vegetable oils, but its deprived pour point characteristics restrict its use as base oil in the development of lubricants. Hence, through chemical modification (alkali-catalysed transesterification), coconut oil is converted into coconut oil methyl ester (CME) thereby improving the pour point from 27°C to −5°C. In the present study, calcium based grease was developed from coconut methyl ester and its tribological properties were evaluated and compared to a commercial sample of the same grade. NLGI grade 3 grease was developed by mixing calcium stearate thickener with CME having premixed additives (TCP-antiwear, Oleic acid-antifriction and Eva-viscosity improver). Tribological properties (consistency, rolling stability, water washout, friction, wear, and corrosion) of the newly formulated grease were evaluated and compared to a commercial sample. Operating temperature of this newly formulated grease was found to be between −7°C and 108°C. Performance of the grease samples was studied using 0.5 HP centrifugal pump. Efficiency, discharge and power consumption of the pump were found to be 6.9%, 1.8% and 4.7% more efficient while using newly formulated grease when compared to commercial sample. These tribological and performance studies infer that the newly formulated grease was competent enough with the commercial sample.
Experimental comparative analysis of hybrid energy harvesters exposed to flow-induced vibrations
Authors: Bolat Fevzi Cakmak , Basaran Sinan , Abdelkefi Abdessattar , Wang Junlei
Published: September 2022

In this study, hybrid energy harvesting based on electromagnetic induction (EM) and piezoelectric transduction (PZT) is experimentally investigated under different conditions of flow-induced vibrations. The energy harvesting performance of the system is examined when the electromagnetic and piezoelectric mechanisms are used both separately and simultaneously. In this regard, firstly, only electromagnetic induction harvesting structure is attached to a beam, and time-dependent voltage and displacement are experimentally investigated. Then, PZT has adhered to the beam, and voltage outputs are measured in both the PZT and EM circuits. The third scenario is based on removing the electromagnetic harvesting structure and only the piezoelectric energy harvesting performance is studied. The mentioned cases are investigated under different excitation circumstances, that is, distinct bluff-body geometries and flow velocities. While the square bluff-body geometry is connected to the structure, both PZT and EM harvested power are determined by considering different electrical load resistances. It is mainly revealed that the total energy amount is higher in the hybrid configuration. After determining the hybrid structure is the most effective, elements with different splitters geometry are attached to the bluff-body geometry of the harvesting structure. Finally, the vibration enhancement potential of these new types of splitters on the harvesting structure is experimentally investigated. For the solo electromagnetic harvester, the maximum power is obtained at an external load resistance value of 10 kΩ, while for the solo PZT harvester, the maximum power is observed at the resistance value of 330 kΩ. Among the three types of splitter geometries examined, the highest voltage was obtained from type-1 as 14.168 V.
Investigation on microstructure and tribological performance of zirconium boride reinforced AZ91D magnesium alloy: Effect of processing routes
Authors: Ayyanar S. , Gnanavelbabu A. , Rajkumar K. , Loganathan P. , Vishal K.
Published: September 2022

The present research explored the effects of spatially dispersed ZrB2 particles on mechanical characteristics, surface-modified tribo layer and the dry sliding wear of the AZ91D alloy composite. The objective of this study was to reduce the porosity and improve the tribo performance of the AZ91D/ZrB2 composite by a squeeze casting, and the results were compared with those of a stir-cast composite. The influence of ZrB2 on mechanical properties such as hardness, tensile strength, and wear analysis of composites by the pin-on-disk technique was studied. The squeeze cast composite showed a higher hardness of 115 HV and ultimate tensile strength of 275 MPa than the stir cast composite. Stir-cast composite reduces particle rearrangement due to cluster formation, resulting in higher porosity and lower mechanical strength, reducing tribo performance. The refinement of grain structure and porosity reduction of up to 31.61% improves strength, leading to better tribological properties for the squeeze cast composites. The squeeze cast composite containing 12 wt% of ZrB2 showed a minimum wear of 0.024 mm3/m, which is 25.14% less than the stir cast composite. The improved wear resistance resulted from a lubricating boron oxide layer (B2O3), confirmed through Raman spectroscopy. Tribo layer, delamination, and plastic deformation were found to be the primary wear mechanisms for the AZ91D/ZrB2 composite that were active throughout the sliding period.
Synthesis of Al2O3/SiO2 core–shell composite abrasives toward ultrasmooth and high-efficiency polishing for sapphire wafers
Authors: Xu Yongchao , Zhao Guangen , Wang Qianting , Zhan Youji , Chen Bingsan
Published: September 2022

A novel Al2O3/SiO2 core–shell composite abrasive was successfully synthesized via a facile sol–gel strategy and utilized to promote the surface quality and polishing efficiency of sapphire wafer. The silica shell with dense and amorphous structure was successfully coated on Al2O3 core. Its synthesis mechanism was discussed deeply, and good dispersibility and uniform particle size were obtained. The acquired core–shell composite particles were employed for the planarization machining of sapphire wafer. Results show that the decrease in surface roughness of Al2O3/SiO2 core–shell composite abrasives during polishing is more than 20.2% of that of pure Al2O3 abrasives, the material removal rate is more than 5.1% of that of pure Al2O3 abrasives, and the residual stress of the sapphire wafer finished by composite abrasives is decreased by approximately 40%. These results demonstrate that the Al2O3/SiO2 core–shell composite abrasives provide a more excellent polishing performance for the sapphire wafer, resulting in smoother and scratch-free surface with a higher material removal rate compared with pure Al2O3 abrasives. On the basis of the reaction product analysis and elastic-plastic micro-contact mechanics, the reasons for the improvement of polishing performance were revealed in terms of chemical corrosion and mechanical abrasion.
Dynamic recrystallization of Ti-6Al-4V titanium alloy based on cellular automata
Authors: Ji Hongchao , Peng Zhanshuo , Huang Xiaomin , Wang Baoyu , Xiao Wenchao , Wang Shufu
Published: September 2022

Ti-6Al-4V (TC4) alloy is a (α + β) two-phase titanium alloy and has good process plasticity, superplasticity, and corrosion resistance. It is widely used in the aerospace industry. During the hot working process, the microstructure and deformation behavior affect its mechanical properties. However, most of the current research focuses on the use of metallographic methods and physical modeling methods to characterize and estimate the evolution of microstructures and lacks accuracy. Therefore, in this study, the thermal deformation behavior of TC4 titanium alloy is predicted and the dynamic recrystallization process is visualized through thermal simulation test, metallographic test, particle swarm optimization–backpropagation (PSO–BP) algorithm, and cellular automata (CA) method. The conclusions are as follows: the grain growth of TC4 titanium alloy is relatively uneven during hot compression. The increase in temperature and the decrease in strain rate are favorable to dynamic recrystallization. After hot compression, the grain texture appeared in the microstructure of TC4 titanium alloy, and the type and strength of texture changed with the change in temperature. Based on the PSO–BP algorithm, the rheological behavior of TC4 titanium alloy during hot compression is predicted. Compared with the experimental value, the correlation of the PSO–BP model is 0.9972, and the error is within 10%. Finally, using the PSO–BP algorithm as the input, combined with the CA method and the related theory of dynamic recrystallization, the dynamic recrystallization behavior of TC4 titanium alloy during hot compression is simulated. The electron backscatter diffraction test is used for comparison, and the simulated microstructure is similar to the experimental structure after removing the influence of some defects. The average grain size error is within 10%. It shows that this model can well predict the dynamic recrystallization behavior of TC4 titanium alloy during hot compression.
Growth, subject areas, and application of research methods in user studies: A content analysis of articles produced by Pakistani authors
Authors: Ullah Ahsan , Ameen Kanwal
Published: September 2022

Information science profession is concerned with information user and every development in this field has been designed to make it easier for the user to access documents or information. The current study examined user studies to provide understanding about the users, growth in user studies, topics, and methods of user studies. A content analysis method has been adopted and empirical research articles produced by Pakistani authors during the period 2001–2016 have been examined. Out of 518 empirical articles, 185 user studies were selected for examining users, subject and methods. Growth in user studies research was lower from the period 2001 to 2008 but number of studies increased significantly after 2008. Dominant majority of user studies collected data from educational institutions. Academicians and students were the most frequently studied users. Bureaucrats, judges, and other officials have not been examined for elicitation of their needs in spite of the fact that libraries have been established with government departments and courts. In respect of research areas of user studies, information needs and seeking behavior, use and skills of internet and social media, use of electronic resources and satisfaction of users with library services constitute 90% of user studies research. With respect to use of research methodology, quantitative approach (78%) is popular in user studies followed by mixed methods (10%), qualitative (8%), and multimethod (4%). More than one method is used in 14% user studies research. In case of frequency of research methods, questionnaire (72%) is the dominant method followed by interview (14%). The current study is unique because it identified popular topics and methods in user studies research.
A call for regulatory reform to make work experience accessible rather than an obstacle
Authors: Hewitt Anne , Grenfell Laura
Published: September 2022

It is widely recognised that a lack of work experience can impede university students seeking graduate employment and that many tertiary students face significant barriers in securing work experience. Drawing on existing research, this article analyses these barriers, and considers the consequences of this inequity for affected individuals as well as for broader Australian society and the economy. The article proposes various ‘do-able’ reforms to the regulation of work integrated learning in tertiary education and student-finance schemes which would go some way to reducing these barriers.
Seromonitoring of brucellosis in goats and sheep slaughtered at an abattoir in Kampala, Uganda
Authors: Kakooza Steven , Watuwa James , Ipola Patrick A. , Munyiirwa Damien F. N. , Kayaga Edrine , Nabatta Esther , Mahero Michael , Ssajjakambwe Paul , Kaneene John B.
Published: September 2022

We conducted a cross-sectional serologic study at Kampala City abattoir in Uganda on 287 small ruminants (221 goats and 66 sheep) to determine the seroprevalence of brucellosis. The samples were tested using a modified rose bengal test (mRBT) and an indirect ELISA (iELISA). Small ruminant Brucella spp. seropositivity was 18 of 287 (6.3%) by mRBT and 19 of 287 (6.6%) by iELISA. The prevalence of brucellosis by mRBT was non-significantly higher in goats (17 of 221; 7.7%) than in sheep (1 of 66, 1.5%; p = 0.069), and also non-significantly higher by the iELISA in goats (18 of 221; 8.1%) than in sheep (1 of 66, 1.5%; p = 0.057). Brucellosis in slaughtered goats and sheep is a public health hazard to abattoir workers and consumers that calls for control and eradication measures at the farm level, given that testing is not carried out routinely at slaughter points.
On the use of Stochastic Bouc–Wen model for simulating viscoelastic internal variables from a finite element approximation of steady-rolling tire
Authors: Raqueti Rafael da S , Teloli Rafael de O , da Silva Samuel , Bussetta Philippe , Cunha Americo
Published: September 2022

Reducing tire rolling resistance and energy loss is a topic of interest to the tire industry. Understanding and modeling these phenomena are essential to approach this problem and propose robust solutions. This work suggests a reduced-order model based on the Bouc–Wen model to simulate internal variables from viscoelastic constitutive laws. Furthermore, sensitivity analysis is performed on the Bouc–Wen parameters to evaluate their influence on the system response and capture the full range of possible values that improve the predictive ability of the reduced-order model. This task is accomplished by calculating the Sobol’s indices estimated from a Polynomial-Chaos expansion. Once the range of feasible model solutions is established, the reduced-order model is calibrated through Bayesian inference. Finally, the uncertainties are propagated, and the reduced-order model is validated using data of viscoelastic internal variables from the finite element approximation of a steady-rolling tire. Satisfactory results are obtained, as the reduced-order model can simulate viscoelastic internal variables with a reduced computational cost for some branches of interest. Its responses are in agreement with the experimental data.
Self-Reported and Agency-Notified Child Abuse as Contributors to Suicidal Behaviour in a Population-Based Birth Cohort Study at 30-Year-Follow-Up
Authors: Kisely Steve , Strathearn Lane , Najman Jake Moses
Published: September 2022

This was a record-linkage analysis of a birth cohort to examine the association between self-reported self-harm in adulthood and childhood maltreatment (CM) as prospectively notified to authorities and self-reported on the Child Trauma Questionnaire. There were 2507 participants at 30-year follow-up with data on both CM and self-reported self-harm including an intent to die. Of the participants, 304 (12.1%) had self-harmed at some time in their lives while 150 (4.2%) had wanted to die. The prevalence of self- and agency-reported maltreatment was 513 (20.5%) and 143 (5.7%) respectively. On adjusted analyses, CM irrespective of reporting source showed significant associations with both suicidal outcomes. Physical and emotional abuse showed the strongest associations while findings for neglect were mixed. The only association for sexual abuse was for self-reported maltreatment and intent to die but numbers may have been under-powered.
Improved hip symmetry with an adjustable fluoroscopic grid during total hip arthroplasty
Authors: DeJesus James , Nishioka Scott , Andrews Samantha N. , Mathews Kristin , Nakasone Cass K
Published: September 2022

Background:

The use of intraoperative fluoroscopy (IF) is common with direct anterior total hip arthroplasty (THA), however image distortion in IF may limit its usefulness. The supplementation of IF with an adjustable grid (AG) may provide consistently better accuracy in component placement. Therefore, the purpose of this study was to compare the accuracy, consistency, and surgical efficiency between IF only and AG supplementation.

Methods:

2 cohorts were retrospectively evaluated, including 573 IF only patients and 211 AG patients having undergone unilateral THA between 2011 and 2018. Post-THA radiographic assessment was performed to evaluate the accuracy of component placement, with target placements for global hip offset (GHO) and leg-length differences (LLD) <10 mm and acetabular cup abduction of 45° (±10°). Accuracy and surgical efficiency were evaluated between groups and over time.

Results:

The AG group had a significant greater percentage of components placed within the target zone compared to IF only for GHO (99.5%, 92.7%, p < 0.001), LLD (99.1%, 96.5%, p = 0.039) and abduction (99.5%, 96.3%, p = 0.009), with no difference in fluoroscopic time ( p = 0.973). Over time, accuracy was significantly different in IF group for GHO ( p = 0.008) and abduction ( p = 0.002) and trended toward significance for LLD ( p = 0.055). There were no significant differences over time for the AG group.

Conclusions:

The addition of an AG to IF significantly increased the accuracy of component placement during direct anterior THA. These results were consistent over 2 years of use and did not decrease surgical efficiency.
The second-order election model and the performance of political parties in municipal elections
Authors: Gendźwiłł Adam , Kjaer Ulrik
Published: September 2022

Elections at the municipal level are often treated as second-order elections (SOE), subordinate to the national electoral arena in a manner similar to the European elections. The original SOE model expects incumbent national parties to perform worse, while predicting smaller and ideologically extreme parties to perform better in the second-order electoral arena compared to the first-order (national) one. Based on a dataset covering aggregate election results in three Nordic countries (Denmark, Norway and Finland) with party-dominated local governments and a time span of more than three decades, we find that the performance of parties in municipal elections only to some degree conforms to the expectations of the model. Parties in national government usually suffer losses in municipal elections, but the effect of incumbency is contingent upon the party size: only large incumbent parties are punished in local elections. We find very weak support for the hypothesis that extreme parties perform better than moderates and suggest that this can be explained by the organisational effort required to field the candidates and campaign in multiple jurisdictions. We conclude that the SOE model should not be applied as a default to municipal elections when explaining political parties’ electoral performance.
Capital gains in a digital society: Exploring how familial habitus shapes digital dispositions and outcomes in three families from Aotearoa, New Zealand
Authors: Keen Caroline , France Alan
Published: September 2022

Persistent concerns about the digital divide are typically framed as a deficit of Internet access, skills or participation. Despite advances remedying first- and second-level divide issues, scholars have found that not all benefit equally from the Internet use resulting in the theorising of a third-level digital divide exploring the social determinants critical to benefit from the Internet use. Presenting analysis for three families from Aotearoa New Zealand, this work highlights the importance of the family in creating children’s digital disposition. Applying Bourdieu’s Theory of Practice concepts, we illustrate how parent’s habitus informs children’s responses to the digital world, shaping diverse forms of ‘digital capital’ which may result in ‘capital gains’ for some, and less capital benefits for others. Findings suggest that the forms of digital capital that are valued by families are closely tied to class positioning and cultural background.
The policy idea of ‘the teacher assistant’: Construction and legitimation through a discursive institutionalist lens
Authors: Lidström Tina
Published: September 2022

Transnational policy discourses shape teacher professionalism through discursive patterns in policy initiatives from the global policy actor, OECD. The policy idea of ‘the teacher assistant’ has emerged through discourses on teacher professionalism, spurring ambiguities regarding what the policy idea is and ought to be in Sweden. The aim of this article is to critically examine the construction and legitimation of the policy idea of ‘the teacher assistant’, in relation to teachers and the educational institution, through the lens of discursive institutionalism and strands in Curriculum Theory. The focus is a critical understanding of the interplay between ideas, discourses, actors and institutional context. The analysis of policy documents shows how the policy idea is constructed and legitimised through actors’ coordinative and communicative discourses at the national level, influenced by the OECD at the transnational level. The policy idea is intertwined with ideas and discourses on teachers’ professional development through a national professional programme and institutional conditions for goal attainment in schools. Tensions emerge regarding underlying assumptions about teacher quality, highlighting ideas of what teachers are and ought to be, within comprehensive reform strategies. Tensions entail emerging ideas of standardisation and differentiation and ambiguities regarding the policy idea of ‘the teacher assistant’.
An overview of additive manufacturing methods, materials, and applications for flexible structures
Authors: Jayswal Ajay , Adanur Sabit
Published: September 2022

Various types of additive manufacturing (AM) methods (also called 3D printing), and materials have been increasingly studied in the field of additive manufacturing of flexible structures such as fabrics, and flexible electronics. Polymer-based AM processes allow the flexibility, rapid, and low-cost fabrication of complex geometries depending on the types of materials used. The purpose of this review article is to summarize the major AM methods, materials, and their emerging applications to additively manufacture the flexible structures. In the AM methods section, Fused Deposition Modeling (FDM), and Selective Laser Sintering (SLS) are reviewed for fabrics, and Direct Ink Writing (DIW) for electronics. In the Materials section, the manufacturing methods, chemical structures, properties, advantages, and limitations of some of the widely used materials in three-dimensional (3D) printing of polymers are reviewed. Third, the applications of these methods and materials for fabrics, and electronics are covered. Finally, the associated opportunities and challenges in 3D printing process of flexible structures are described. The future research should be related to the exploration of combinations and development of innovative materials, printing process parameters, detail study on improving the properties, and hybrid 3D printing process.
Supporting shipboard helicopter flight testing with simulation and metrics for predicting pilot workload
Authors: Comeau Perry , Wall Alanna , Thornhill Eric , McTavish Sean , Lee Richard
Published: September 2022

Shipboard helicopter operations are much more challenging and complex than land-based operations due to many factors associated with the presence of the ship. To determine those conditions in which safe operations may occur, a First of Class Flight Trial (FOCFT) is conducted for every new ship–helicopter pair. This trial results in a Ship–Helicopter Operating Limit (SHOL) envelope that is used to document operational limits for regular operations. Conducting a FOCFT is a, expensive, and time-consuming task that requires testing all aspects of operations. Modeling and simulation efforts to support shipboard helicopter operations have been ongoing internationally for many years with the intention of de-risking FOCFT and introducing efficiency into the testing process. Canada will be accepting several new ship classes into its fleet over the next two decades. In support of FOCFT for these new ships, modeling and simulation tools are being developed by the National Research Council (NRC) Canada and Defence Research and Development Canada (DRDC) and significant advancements have occurred in the past decade. As part of this work, NRC and DRDC now use a framework and analysis approach that is intended to standardize SHOL testing with the use of modeling and simulation. This paper introduces that framework and gives details on the modeling and simulation tools that can be used to reduce risk and increase efficiency for Canada’s upcoming FOCFTs.
‘When the bedbugs come, that’s another problem’: exploring the lived experiences of bedbug infestations among low-income older adults and service providers who support them
Authors: Sheppard CL , Roche B , Austen A , Hitzig SL
Published: September 2022

Aims:

Older adults in low-income housing communities are more vulnerable to bedbug infestations. Prior research, however, has predominately focused on the effectiveness of integrated pest-management strategies, with little attention given to the lived experiences of tenants struggling with infestations. We used a qualitative approach to explore what it is like to live with and treat bedbug infestations from the perspectives of low-income older adults and service providers.

Methods:

Participants included low-income older adults ( n = 58) and service providers ( n = 58) who offer supports directly in the buildings. Semi-structured qualitative interviews and focus groups were used to explore the challenges of preparing and treating units for bedbugs, and examine how bedbugs impact access to support services.

Results:

Bedbugs were a widespread issue, and underlying physical, mental, social, and financial challenges made it difficult for older tenants to prepare their units and access treatment. Tenants also faced bedbug stigma from community services, as many were unwilling to provide services in infested units. Although some service providers utilized strategies to minimize exposure, many were concerned these strategies created additional stigma.

Conclusion:

Our findings highlight an urgent need to increase public health funding to support older adults with the costs of bedbug elimination and to enhance pest-management strategies through partnerships with health and social service agencies to improve outcomes for older adults.
Heroines who are rebuilding their country: State–society circumstances and coping strategies of female leaders in post-genocide Rwanda
Authors: Li Jie , Batamuliza Mireille , Karangwa Evariste
Published: September 2022

The labor arrangement of industrial society makes “production and reproduction” a contradiction that is both separate and interdependent. One of the significant consequences is the re-establishment of the responsibilities and boundaries of production and reproduction between the modern state, market, family, and gender. After the genocide against the Tutsi in 1994, Rwanda has made world-renowned achievements in advancing gender equality, especially women's participation in politics. It is the “twofold full-time producers” model that continuously sustains this huge achievement, which means that female leaders not only bear a highly demanding responsibility for production, comparable to men, but also undertake significant labor in social reproduction. The public policy of Rwanda has assumed a dual role in this process: on the one hand, the state has promulgated a series of gender equality bills, policies, and measures from top to bottom that actively promote women's equal rights in various fields, especially their political participation. On the other hand, against the background of a severe labor shortage and insufficient public welfare facilities, the responsibility of private families for social reproduction has been maintained and strengthened, while the traditional family structure and community culture's share of responsibility for reproduction has been irreversibly weakened during the conflict and modernization process. While these female leaders rely on their individual strategies and informal social support systems to cope with the dual burden, they still face scrutiny and doubt from the community culture. The consensus on the destiny of the country's development and the sharing of historical responsibilities demonstrated by Rwanda's female leaders shares many similarities with the Chinese women's liberation movement, which also provides an important inspiration and reference point for rethinking the path of women's liberation characterized by economic independence and “the supremacy of production”.
Decompression Alone in the Setting of Adult Degenerative Lumbar Scoliosis and Stenosis: A Systematic Review and Meta-Analysis
Authors: Echt Murray , De la Garza Ramos Rafael , Geng Eric , Isleem Ula , Schwarz Julia , Girdler Steven , Platt Andrew , Bakare Adewale A , Fessler Richard G , Cho Samuel K
Published: September 2022

Study Design

Systematic review and meta-analysis. OBJECTIVESSurgical decompression alone for patients with neurogenic leg pain in the setting of degenerative lumbar scoliosis (DLS) and stenosis is commonly performed, however, there is no summary of evidence for outcomes.

Methods

A systematic search of English language medical literature databases was performed for studies describing outcomes of decompression alone in DLS, defined as Cobb angle >10˚, and 2-year minimum follow-up. Three outcomes were examined: 1) Cobb angle progression, 2) reoperation rate, and 3) ODI and overall satisfaction. Data were pooled and weighted averages were calculated to summarize available evidence.

Results

Across 15 studies included in the final analysis, 586 patients were examined. Average preoperative and postoperative Cobb angles were 17.6˚ (Range: 12.7 - 25˚) and 18.0 (range 14.1 - 25˚), respectively. Average change in Cobb angle was an increase of 1.8˚. Overall rate of reoperation ranged from 3 to 33% with an average of 9.7%. Average ODI before surgery, after surgery, and change in scores were 56.4%, 27.2%, and an improvement of 29% respectively. Average from 8 studies that reported patient satisfaction was 71.2%.

Conclusions

Current literature on decompression alone in the setting of DLS is sparse and is not high quality, limited to patients with small magnitude of lumbar coronal Cobb angle, and heterogenous in the type of procedure performed. Based on available evidence, select patients with DLS who undergo decompression alone had minimal progression of Cobb angle, relatively low reoperation rate, and favorable patient-reported outcomes.
Teaching Public Health Program Planning: Service Learning in an Online Format
Authors: Leistner Christine E. , S. Machado Stephanie , Gallardo Brianna , McCommon Allison
Published: September 2022

Service-learning has many benefits for undergraduate students in health promotion. Research on health promotion service-learning in an online format, however, is limited. This pilot study aims to evaluate a fully online, undergraduate health promotion service-learning course from the perspective of students enrolled in the course, the project recipients, and the partnering organizations. We also provide details about the course development and process as a resource for faculty teaching health promotion programing and evaluation courses with a service-learning component. College students enrolled in the course ( n = 44) completed a survey to assess learning outcomes. Service-learning program recipients (high school students; n = 127) completed a survey to assess program satisfaction, and teachers from the partnering schools ( n = 4) participated in interviews to explore program perceptions. College students had high confidence in their ability to conduct a needs assessment (91%), develop a program plan (93%), and implement (91%) and evaluate (89%) a health program. The majority of high school students reported that the program was interesting (65%), engaging (86%), and that they learned something new (62%). Teachers reported valuing the program, yet suggested multiple strategies to improve engagement online, including the use of interactive technologies and developing a rapport with students. This study suggests that an online format is appropriate for facilitating health promotion skill development among college students and provides recommendations for future faculty to strengthen course design and partnerships in an online setting.
Assessing managerial patient safety practices that influence adverse events reporting among nurses in the Savannah Region, Ghana
Authors: Alhassan Samson , Kwashie Atswei Adzo , Paarima Yennuten , Ansah Ofei Adelaide Maria
Published: September 2022

Introduction

Patient safety is a global concern for both health professionals and the public. Studies show that evaluating patient safety culture can help improve patient safety outcomes. Nursing care strategically places nurses at the centre of patient safety promotion and their proximity to patients makes them the drivers of patient safety. Managerial decisions regarding patient safety impact greatly on patient safety outcomes in the healthcare organization. This study aimed to assess the managerial patient safety practices that influence adverse event reporting in three hospitals in the Savannah Region of Ghana.

Methods

A quantitative cross-sectional design was used to collect data from 210 participants in three hospitals. Data were analysed using descriptive, Pearson's correlation and linear regression.

Results

It was found that patient safety practices with good positive rating scores were management support (56.6%), managers' expectations (62.8%) and feedback about errors (56.2%). Areas with weak patient safety practices were staffing levels (42.4%), open communication (40.2%) and non-punitive response to errors (36.7%). Again, nurses' attitude towards adverse events reporting was generally low (37.3%). Managerial patient safety practices that had significant associations with adverse events reporting were management support ( r = .18, p < .001), open communication ( r = .19, p < .001), non-punitive to errors ( r = .21, p < .001) and feedback about errors ( r = .37, p < .001). Again, the significant predictors of adverse events reporting were feedback about errors ( β  =  .36, p < .001) and non-punitive response to errors ( β  =  .21, p  < .01).

Conclusion

Nurses perceived patient safety culture in their units to be good. Although nurses' attitude towards adverse events reporting was low, the significant predictors of adverse events reporting were feedback about errors and non-punitive response to errors. Therefore, healthcare managers should continually strengthen patient safety to ensure optimal care outcomes.

Implications for nursing practice

Feedback on errors and non-punitive response to errors had a great influence on adverse events reporting, managerial failure to provide feedback and a non-punitive work environment could result in under-reporting of adverse events. This can be a major threat to patient safety; hence clinical practice should be aware of this and put in strategies to appropriately address them.
Effectiveness of home-based pulmonary rehabilitation: systematic review and meta-analysis
Authors: Uzzaman Md. Nazim , Agarwal Dhiraj , Chan Soo Chin , Patrick Engkasan Julia , Habib G.M. Monsur , Hanafi Nik Sherina , Jackson Tracy , Jebaraj Paul , Khoo Ee Ming , Mirza Fatim Tahirah , Pinnock Hilary , Shunmugam Ranita Hisham , Rabinovich Roberto A.
Published: September 2022

Introduction

Despite proven effectiveness for people with chronic respiratory diseases, practical barriers to attending centre-based pulmonary rehabilitation (centre-PR) limit accessibility. We aimed to review the clinical effectiveness, components and completion rates of home-based pulmonary rehabilitation (home-PR) compared to centre-PR or usual care.

Methods and analysis

Using Cochrane methodology, we searched (January 1990 to August 2021) six electronic databases using a PICOS (population, intervention, comparison, outcome, study type) search strategy, assessed Cochrane risk of bias, performed meta-analysis and narrative synthesis to answer our objectives and used the Grading of Recommendations, Assessment, Development and Evaluations framework to rate certainty of evidence.

Results

We identified 16 studies (1800 COPD patients; 11 countries). The effects of home-PR on exercise capacity and/or health-related quality of life (HRQoL) were compared to either centre-PR (n=7) or usual care (n=8); one study used both comparators. Compared to usual care, home-PR significantly improved exercise capacity (standardised mean difference (SMD) 0.88, 95% CI 0.32–1.44; p=0.002) and HRQoL (SMD −0.62, 95% CI −0.88–−0.36; p<0.001). Compared to centre-PR, home-PR showed no significant difference in exercise capacity (SMD −0.10, 95% CI −0.25–0.05; p=0.21) or HRQoL (SMD 0.01, 95% CI −0.15–0.17; p=0.87).

Conclusion

Home-PR is as effective as centre-PR in improving functional exercise capacity and quality of life compared to usual care, and is an option to enable access to pulmonary rehabilitation.
Ancestry-related distribution of Runs of homozygosity and functional variants in Qatari population
Authors: Mezzavilla Massimo , Cocca Massimiliano , Maisano Delser Pierpaolo , Badii Ramin , Abbaszadeh Fatemeh , Hadi Khalid Abdul , Giorgia Girotto , Gasparini Paolo
Published: September 2022

Background

Describing how genetic history shapes the pattern of medically relevant variants could improve the understanding of how specific loci interact with each other and affect diseases and traits prevalence. The Qatari population is characterized by a complex history of admixture and substructure, and the study of its population genomic features would provide valuable insights into the genetic landscape of functional variants. Here, we analyzed the genomic variation of 186 newly-genotyped healthy individuals from the Qatari peninsula.

Results

We discovered an intricate genetic structure using ancestry related analyses. In particular, the presence of three different clusters, Cluster 1, Cluster 2 and Cluster 3 (with Near Eastern, South Asian and African ancestry, respectively), was detected with an additional fourth one (Cluster 4) with East Asian ancestry. These subpopulations show differences in the distribution of runs of homozygosity (ROH) and admixture events in the past, ranging from 40 to 5 generations ago. This complex genetic history led to a peculiar pattern of functional markers under positive selection, differentiated in shared signals and private signals. Interestingly we found several signatures of shared selection on SNPs in the FADS2 gene, hinting at a possible common evolutionary link to dietary intake. Among the private signals, we found enrichment for markers associated with HDL and LDL for Cluster 1(Near Eastern ancestry) and Cluster 3 (South Asian ancestry) and height and blood traits for Cluster 2 (African ancestry).

The differences in genetic history among these populations also resulted in the different frequency distribution of putative loss of function variants. For example, homozygous carriers for rs2884737, a variant linked to an anticoagulant drug (warfarin) response, are mainly represented by individuals with predominant Bedouin ancestry (risk allele frequency G at 0.48).

Conclusions

We provided a detailed catalogue of the different ancestral pattern in the Qatari population highlighting differences and similarities in the distribution of selected variants and putative loss of functions. Finally, these results would provide useful guidance for assessing genetic risk factors linked to consanguinity and genetic ancestry.
A 'good dyadic relationship' between older couples with one having mild cognitive impairment: a Q-methodology
Authors: Cheung Daphne Sze Ki , Ho Grace Wing Ka , Chan Athena Chung Yin , Ho Ken Hok Man , Kwok Robin Ka Ho , Law Yammie Pui Yan , Bressington Daniel
Published: September 2022

Background

Cognitive impairment gradually brings changes to the relationship between older married couples. Therefore, this study aimed to understand the individual viewpoints of couple dyads on the important attributes of a 'good dyadic relationship' in the context of mild cognitive impairment (MCI), and to explore if the congruencies and discrepancies in their perceptions related to the quality and closeness of their relationship and well-being.

Methods

Q-methodology was used to reveal the perceptions of a ‘good dyadic relationship’ among couples with one having MCI. The participating couples were separated in two rooms and independently ranked 18 relationship attributes from least to most important on a 7-point Q-sort response grid. All participants also completed a post-sort interview and surveys to assess their psychological well-being and closeness. Q-sorts were analyzed using by-person factor analysis.

Results

Forty people with MCI and forty spousal partners completed the Q-sort. Three viewpoints, accounting for 48% of the total variance, were identified and were labeled ‘Provider,’ ‘Problem-solver,’ and ‘Partner.’ Different viewpoints of a ‘good dyadic relationship’ primarily varied by perceived importance of commitment, dedication, tolerance, and personal space. Despite these differences, there was wide consensus that respecting each other and cherishing the current moment are two universally salient attributes of a good relationship across all viewpoints. Couples with discrepant views scored significantly higher on perceptions of the quality of the relationship and closeness with the partner.

Conclusions

This study advances the theoretical understanding of the dyadic relationship between couples with one having MCI, from both perspectives. MCI is a state in which couples can openly discuss their expectations. The findings provide practitioners with insights to work with couples experiencing MCI.
Nuclear receptor ligand screening in an iPSC-derived in vitro blood–brain barrier model identifies new contributors to leptin transport
Authors: Shi Yajuan , Kim Hyosung , Hamann Catherine A. , Rhea Elizabeth M. , Brunger Jonathan M. , Lippmann Ethan S.
Published: September 2022

Background

The hormone leptin exerts its function in the brain to reduce food intake and increase energy expenditure to prevent obesity. However, most obese subjects reflect the resistance to leptin even with elevated serum leptin. Considering that leptin must cross the blood–brain barrier (BBB) in several regions to enter the brain parenchyma, altered leptin transport through the BBB might play an important role in leptin resistance and other biological conditions. Here, we report the use of a human induced pluripotent stem cell (iPSC)-derived BBB model to explore mechanisms that influence leptin transport.

Methods

iPSCs were differentiated into brain microvascular endothelial cell (BMEC)-like cells using standard methods. BMEC-like cells were cultured in Transwell filters, treated with ligands from a nuclear receptor agonist library, and assayed for leptin transport using an enzyme-linked immune sorbent assay. RNA sequencing was further used to identify differentially regulated genes and pathways. The role of a select hit in leptin transport was tested with the competitive substrate assay and after gene knockdown using CRISPR techniques.

Results

Following a screen of 73 compounds, 17β-estradiol was identified as a compound that could significantly increase leptin transport. RNA sequencing revealed many differentially expressed transmembrane transporters after 17β-estradiol treatment. Of these, cationic amino acid transporter-1 (CAT-1, encoded by SLC7A1) was selected for follow-up analyses due to its high and selective expression in BMECs in vivo. Treatment of BMEC-like cells with CAT-1 substrates, as well as knockdown of CAT-1 expression via CRISPR-mediated epigenome editing, yielded significant increases in leptin transport.

Conclusions

A major female sex hormone, as well as an amino acid transporter, were revealed as regulators of leptin BBB transport in the iPSC-derived BBB model. Outcomes from this work provide insights into regulation of hormone transport across the BBB.
A qualitative study exploring teachers’ beliefs regarding breastfeeding education in family and consumer sciences classrooms
Authors: Singletary Nicola , Bruce Jackie , Goodell L. Suzanne , Fogleman April
Published: September 2022

Background

Research shows that elementary and secondary school children have considered infant feeding choices for when they become parents and are interested in learning about breastfeeding in school. Despite recommendations to include infant feeding education in secondary school classrooms, teachers’ practices and attitudes regarding this topic have been the subject of minimal research. The purpose of this study was to explore North Carolina, USA, family and consumer sciences teachers’ infant feeding education practices and their views on incorporating breastfeeding education in the curricula of family and consumer sciences classes that cover topics related to parenting and nutrition.

Methods

The study used a purposive sample of 19 teachers who participated in semi-structured qualitative telephone interviews exploring their attitudes and practices relating to infant feeding education. We transcribed and analyzed the interviews using the constant comparative method through the lens of the Theory of Planned Behavior by examining the participants’ attitudes, subjective norms, and perceived behavioral controls.

Results

Teachers had predominantly positive attitudes towards the inclusion of breastfeeding education in high school parenting, child development, and nutrition courses, citing the need to normalize breastfeeding and support students’ ability to make informed choices when they become parents. Teachers’ subjective norms included concerns about parents’ and administrators’ views on the appropriateness of the content and apprehension about negative student responses. Perceived behavioral controls included student maturity, teachers’ own experiences and comfort with infant feeding, and the view that curriculum guidelines limit content selection.

Conclusions

The results of this study can be used in the development and implementation of secondary school education programs that increase knowledge about infant feeding and positive attitudes towards breastfeeding for all members of the community. Teachers’ concerns need to be addressed in the implementation of these programs.
Successful treatment with femoro-femoral venovenous extracorporeal membrane oxygenation in traumatic tracheal injury: a case report
Authors: Ko Haein , Oh Sang Gi , Song Sang Yun , Lee Kyo Seon , Kim Do Wan
Published: September 2022

Background

Traumatic tracheal injury is a rare type of trauma. In this type of injury, catastrophes may occur owing to a failure to secure the patient's airway. Extracorporeal membrane oxygenation (ECMO) is rescue therapy available for the treatment of urgent cardiorespiratory distress until the patient's vital signs have stabilized. The various applications of ECMO configurations have expanded the scope for this therapy.

Case presentation

We describe the case of a 66-year-old man with tracheal rupture with thyroid cartilage fracture due to cultivator handle who was treated with veno-venous ECMO. This case reflects the role and limitations of veno-venous ECMO, in which patient survival was possible with a bi-femoral configuration while also ensuring a clear airway.

Conclusion

We shared our experience with bi-femoral veno-venous ECMO as a therapeutic option to contribute to choosing an appropriate approach. Based on our review of the literature, the present case was an uncommon report of survival after tracheal rupture due to trauma without other complications.
Retraction Note: SETDB1 promotes glioblastoma growth via CSF-1-dependent macrophage recruitment by activating the AKT/mTOR signaling pathway
Authors: Han Shuai , Zhen Wei , Guo Tongqi , Zou Jianjun , Li Fuyong
Published: September 2022

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1186/s13046-020-01730-8.