bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-Term Results of Surgery Compared With Nonoperative Treatment for Lumbar Degenerative Spondylolisthesis in the Spine Patient Outcomes Research Trial (SPORT)
Authors: Abdu William A. , Sacks Olivia A. , Tosteson Anna N.A. , Zhao Wenyan , Tosteson Tor D. , Morgan Tamara S. , Pearson Adam , Weinstein James N. , Lurie Jon D.
Published: April 2018

Study Design.

Randomized trial with a concurrent observational cohort study.

Objective.

To compare 8-year outcomes between surgery and nonoperative care and among different fusion techniques for symptomatic lumbar degenerative spondylolisthesis (DS).

Summary of Background Data.

Surgical treatment of DS has been shown to be more effective than nonoperative treatment out to 4 years. This study sought to further determine the long-term (8-year) outcomes.

Methods.

Surgical candidates with DS from 13 centers with at least 12 weeks of symptoms and confirmatory imaging were offered enrollment in a randomized controlled trial (RCT) or observational cohort study (OBS). Treatment consisted of standard decompressive laminectomy (with or without fusion) versus standard nonoperative care. Primary outcome measures were the Short Form-36 (SF-36) bodily pain and physical function scores and the modified Oswestry Disability Index at 6 weeks, 3 months, 6 months, and yearly up to 8 years.

Results.

Data were obtained for 69% of the randomized cohort and 57% of the observational cohort at the 8-year follow up. Intent-to-treat analyses of the randomized group were limited by high levels of nonadherence to the randomized treatment. As-treated analyses in the randomized and observational groups showed significantly greater improvement in the surgery group on all primary outcome measures at all time points through 8 years. Outcomes were similar among patients treated with uninstrumented posterolateral fusion, instrumented posterolateral fusion, and 360° fusion.

Conclusion.

For patients with symptomatic DS, patients who received surgery had significantly greater improvements in pain and function compared with nonoperative treatment through 8 years of follow-up. Fusion technique did not affect outcomes.

Level of Evidence: 1
Eliminating Survivor Bias in Two-stage Instrumental Variable Estimators
Authors: Vansteelandt Stijn , Walter Stefan , Tchetgen Tchetgen Eric
Published: April 2018

Mendelian randomization studies commonly focus on elderly populations. This makes the instrumental variables analysis of such studies sensitive to survivor bias, a type of selection bias. A particular concern is that the instrumental variable conditions, even when valid for the source population, may be violated for the selective population of individuals who survive the onset of the study. This is potentially very damaging because Mendelian randomization studies are known to be sensitive to bias due to even minor violations of the instrumental variable conditions. Interestingly, the instrumental variable conditions continue to hold within certain risk sets of individuals who are still alive at a given age when the instrument and unmeasured confounders exert additive effects on the exposure, and moreover, the exposure and unmeasured confounders exert additive effects on the hazard of death. In this article, we will exploit this property to derive a two-stage instrumental variable estimator for the effect of exposure on mortality, which is insulated against the above described selection bias under these additivity assumptions.
Air-splinting Maneuver During Flexible Bronchoscopy
Authors: Magazine Rahul , Chogtu Bharti
Published: April 2018

Background:

Magazine’s maneuver was developed for ease of insertion of the flexible bronchoscope, on encountering a closed lumen at the nasopharynx-oropharynx junction. The purposes of this study were to find the frequency of occurrence of such luminal closures and to compare the efficacy of Magazine’s maneuver, with other variations of the maneuver, in improving visualization of the upper airway.

Materials and Methods:

Patients aged 18 years and above who were undergoing flexible bronchoscopy were included, and their demographic and clinical data were noted. The bronchoscope was inserted using the transnasal approach, and, at the junction of nasopharynx with oropharynx, the patency of the lumen between the soft palate and the posterior pharyngeal wall was recorded. The subjects were instructed to perform 4 variations of the maneuver. Observations at each variation were recorded as lumen open or closed; if the lumen was open, the size was noted as small or large and whether it closed during expiration.

Results:

Among 443 subjects, obstruction at the nasopharynx-oropharynx junction was observed, at baseline, in 105 (23.7%); whereas 338 (76.3%) had an open lumen. An open lumen was observed during nose and mouth breathing in 294 (66.4%) subjects, and, when head-tilt chin-lift was added to it, it was observed in 303 (68.4%). During Magazine’s maneuver the lumen remained open in all 443 (100%) subjects. Half of the subjects (n=8) with body mass index >30 and one-third (n=29) above 65 years of age had luminal closure at baseline.

Conclusion:

Magazine’s maneuver opens up the obstruction at the nasopharynx-oropharynx junction, whereas mouth and nose breathing mostly fails to do so. Adding head-tilt chin-lift to either of the 2 breathing techniques does not provide any additional benefit.
Levels of Hemolysis Markers in Erythrocyte Concentrates Administered Using a Syringe Infusion Pump
Authors: Gannam Fernanda Figueiredo , Belela-Anacleto Aline Santa Cruz , Kusahara Denise Miyuki , Gonçalves Pedreira Mavilde
Published: April 2018

Syringe infusion pumps (SIPs) led to major advances in infusion therapy and were gradually applied to the transfusion of packed red blood cells (RBCs), raising questions about possible cell damage. The objectives of this study were to determine levels of hematocrit (%), total hemoglobin (g/dL), free hemoglobin (g/dL), lactate dehydrogenase (units/L), potassium (mmol/L), the degree of hemolysis (%) of RBCs infused by an SIP, and to investigate the influence of the infusion rate. The experimental study comprised 14 RBCs, 3 SIPs, and infusion rates of 5, 10, and 20 mL/h. The results showed total hemoglobin reduction (P = .003), and increased free hemoglobin and hemolysis (P <.001) were identified. The conclusion reached was that RBCs presented changes in free hemoglobin and degree of hemolysis.
Routine Versus Clinically Indicated Short Peripheral Catheter Replacement
Authors: Stevens Catherine , Milner Kerry A. , Trudeau Jennifer
Published: April 2018

Despite current, high-quality, level 1 evidence that supports clinically indicated short peripheral catheter (SPC) replacement, the current practice in the health care system studied was to change SPCs routinely every 96 hours. A before-and-after design was used to evaluate the impact of SPC replacement when clinically indicated. Following the practice change, there were no SPC-related infections, monthly phlebitis rates ranged from 1.9% to 3.5%, and SPC use decreased by 14.2%, resulting in estimated cost savings of $2100 and 70 hours of nursing time saved. The translation of evidence on timing of SPC replacement into practice was a success.
Student Self-evaluation After Nursing Examinations
Authors: Butzlaff Alice , Gaylle Debrayh , O’Leary Kelley Colleen
Published: April 2018

Examination wrappers are a self-evaluation tool that uses metacognition to help students reflect on test performance. After examinations, rather than focus on points earned, students learn to self-identify study strategies and recognize methods of test preparation. The purpose of the study was to determine if the use of an examination wrapper after each test would encourage students to self-evaluate performance and adjust study strategies. A total of 120 undergraduate nursing students completed self-evaluations after each examination, which were analyzed using content analysis. Three general patterns emerged from student self-evaluation: effective and ineffective study strategies, understanding versus memorization of content, and nurse educator assistance.
Using the BODY-Q to Understand Impact of Weight Loss, Excess Skin, and the Need for Body Contouring following Bariatric Surgery
Authors: Klassen Anne F. , Kaur Manraj , Breitkopf Trisia , Thoma Achilles , Cano Stefan , Pusic Andrea
Published: April 2018

Background:

A consequence of bariatric surgery is redundant skin for most patients. The authors measured health-related quality of life and appearance following bariatric surgery in relation to weight loss, excess skin, and need for body contouring.

Methods:

The sample included Canadian participants from the BODY-Q field-test study recruited between November of 2013 and July of 2014. Participants were invited to complete BODY-Q scales and questions to assess weight loss, amount of excess skin, and need for body contouring between June 7, 2016, and November 29, 2016.

Results:

Two hundred fourteen participants responded (75 percent response rate). Of the 210 who underwent bariatric surgery, most were left with excess skin [n = 196 (93 percent)] and needed body contouring [n = 168 (80 percent)]. Higher percentage total weight loss correlated with more excess skin (r = 0.24, p = 0.001), the need for more body contouring procedures (r = 0.29, p < 0.001), and (worse) scores on seven of 13 BODY-Q scales. Having redundant skin correlated with more physical symptoms (r = 0.31, p < 0.001), the need for more body contouring procedures (r = 0.62, p < 0.001), and lower scores on 12 BODY-Q scales. The need for more body contouring procedures correlated with more physical symptoms (r = 0.23, p = 0.001) and lower scores on 12 BODY-Q scales.

Conclusions:

Excess skin after bariatric surgery is a disabling problem. Additional research using the BODY-Q is needed to determine improvements that can be achieved following body contouring.
Rotator Cuff Tear Morphologic Parameters at Magnetic Resonance Imaging: Relationship With Muscle Atrophy and Fatty Infiltration and Patient-Reported Function and Health-Related Quality of Life
Authors: Bureau Nathalie J. , Deslauriers Maguy , Lepage-Saucier Marianne , Rouleau Dominique M. , Roy André , Tétreault Patrice , Hagemeister Nicola
Published: April 2018

Objective

The aim of this study was to determine the relationship between rotator cuff tear (RCT) morphologic parameters and muscle atrophy and fatty infiltration, and patient-reported outcome measures, in patients with symptomatic full-thickness RCT.

Methods

Rotator cuff tear location, length, width, thickness, and musculotendinous junction position were assessed in 57 magnetic resonance imaging scans and correlated to the outcome measures using multivariate regression analysis.

Results

Supraspinatus tendon tear length (odds ratio [OR], 2.218; 95% confidence interval [CI], 1.460–3.370), supraspinatus musculotendinous junction position (OR, 2.037; 95% CI, 1.322–3.137), and infraspinatus tendon tear width (OR, 2.371; 95% CI, 1.218–4.615) were identified as the strongest determinants of supraspinatus muscle atrophy, supraspinatus muscle fatty infiltration, and infraspinatus muscle fatty infiltration, respectively.

Conclusions

The extent of supraspinatus tendon and musculotendinous junction retraction influences the development of supraspinatus muscle atrophy and fatty infiltration, whereas the extent of infraspinatus tendon tear width influences the development of infraspinatus muscle fatty infiltration. Morphologic parameters defining RCT at magnetic resonance imaging did not correlate with clinical shoulder function scores.
Risk Factors Associated With Incomplete Colonoscopy Based on the Analysis of Computed Tomographic Colonography Findings
Authors: Lee Eun Sun , Kim Byung Chang , Hur Bo Yun , Kim Min Ju , Park Hyun Jeong , Park Sung Bin , Lee Jong Beum , Sohn Dae Kyung , Han Kyung Su , Hong Chang Won
Published: April 2018

Objective

This study aimed to identify the computed tomographic colonography (CTC) findings of incomplete colonoscopy compared with those of complete colonoscopy.

Methods

The clinical data and CTC imaging data from January 2004 to December 2012 were retrospectively obtained at 2 different institutions and reviewed by the central review system. A total of 71 patients who underwent both videocolonoscopy and CTC were included in this study. The CTC findings and clinical data were evaluated for the completeness of colonoscopy.

Results

In the CTC analysis, differences in total colon length, abdominal circumference, and sigmoid colon diameter were statistically significant between both groups (P < 0.05). Body mass index (BMI) and height were identified as significant clinical factors influencing the completeness of colonoscopy. In multiple logistic regression tests, only BMI and sigmoid colon diameter were independent factors (P < 0.05).

Conclusions

High BMI larger diameter of sigmoid colon was associated with incomplete colonoscopy based on CTC.
Microwave Radiometry-Derived Thermal Changes of Small Joints as Additional Potential Biomarker in Rheumatoid Arthritis
Authors: Pentazos George , Laskari Katerina , Prekas Kleanthis , Raftakis John , Sfikakis Petros P. , Siores Elias
Published: April 2018

Objective

A prospective pilot study was performed using microwave radiometry (MR), a noninvasive method detecting in-depth tissue temperature, to evaluate whether temperature-of-small-joint–derived scores correlate to parameters commonly used to assess disease activity in rheumatoid arthritis (RA).

Methods

Ten patients with active, untreated RA underwent clinical and laboratory assessments and joint ultrasound and MR of hand and foot small joints at baseline and at 15, 30, and 90 days after treatment onset. Mixed-model analysis for repeated measures was used to compare patient characteristics in sequential visits. Twenty age- and sex-matched healthy individuals served as control subjects.

Results

Using 1248 MR-derived separate recordings from patients' joints, several thermoscores involving different joint combinations were created. When compared with clinical and ultrasound data, the best performing thermoscore involved temperatures of 16 joints (second to fifth metacarpal and proximal interphalangeal joints, bilaterally). This thermoscore correlated to the 28-joint Disease Activity Score–C-reactive protein, tender and swollen joint counts, patient's visual analog scale (all P ≤ 0.02), and the standard 7-joint ultrasound score (P < 0.03) and could also discriminate patients in high (mean, 9.2 [SD, 5.6]) or moderate (7.1 [SD, 3.5]) versus low disease activity/remission (4.2 [SD, 1.8]) (P ≤ 0.01) or healthy subjects (5.0 [SD, 1.7]) (P = 0.002).

Conclusions

Microwave radiometry–derived increased in-depth temperature indicative of local inflammation of small joints may serve as an additional biomarker in RA. Optimization of MR-based methods may result in objective assessments of RA disease activity in clinical practice.
Mapping Social Ecological Systems Archetypes
Authors: Rocha Juan , Malmborg Katja , Gordon Line , Brauman Kate , DeClerk Fabrice
Published: April 2018

While sustainable development goals are by their nature global, their achievement requires local action and thus targeting and monitoring sustainable solutions tailored to different social and ecological contexts. Ostrom stressed that there are no panaceas or universal solutions to environmental problems, and developed a social-ecological systems’ (SES) framework -a nested multi-tier set of variables- to help diagnose problems, identify complex interactions, and solutions tailored to each SES arena. The framework has been applied to over a hundred cases, typically reflecting in-depth analysis of local case studies, but with relatively small coverage in space and time. While case studies are context rich and necessary, it can be difficult to upscale their lessons to policy making realms. Here we develop a data driven method for upscaling Ostrom’s SES framework and apply it to a context where data is scarce, incomplete, but also where sustainable solutions are needed. The purpose of upscaling the framework is to create a tool that facilitates decision-making on data scarce contexts such as developing countries. We mapped SES by applying the SES framework to poverty alleviation and food security issues in the Volta River basin in Ghana and Burkina Faso. We found archetypical configurations of SES in space. Given data availability, we study their change over time, and discuss where agricultural innovations such as water reservoirs might have a stronger impact at increasing food security and therefore alleviating poverty and hunger. We conclude by outlining how the method can be used in other SES comparative studies.
Connectivity Problems on Heterogeneous Graphs
Authors: Wu Jimmy , Khodaverdian Alex , Weitz Benjamin , Yosef Nir
Published: April 2018

Background

Network connectivity problems are abundant in computational biology research, where graphs are used to represent a range of phenomena: from physical interactions between molecules to more abstract relationships such as gene co-expression. One common challenge in studying biological networks is the need to extract meaningful, small subgraphs out of large databases of potential interactions. A useful abstraction for this task turned out to be the Steiner network problems: given a reference “database” graph, find a parsimonious subgraph that satisfies a given set of connectivity demands. While this formulation proved useful in a number of instances, the next challenge is to account for the fact that the reference graph may not be static. This can happen for instance, when studying protein measurements in single cells or at different time points, whereby different subsets of conditions can have different protein milieu.

Results and Discussion

We introduce the condition Steiner network problem in which we concomitantly consider a set of distinct biological conditions. Each condition is associated with a set of connectivity demands, as well as a set of edges that are assumed to be present in that condition. The goal of this problem is to find a minimal subgraph that satisfies all the demands through paths that are present in the respective condition. We show that introducing multiple conditions as an additional factor makes this problem much harder to approximate. Specifically, we prove that for C conditions, this new problem is NP-hard to approximate to a factor of C – ϵ, for every C ≥ 2 and ϵ > 0, and that this bound is tight. Moving beyond the worst case, we explore a special set of instances where the reference graph grows monotonically between conditions, and show that this problem admits substantially improved approximation algorithms. We also developed an integer linear programming solver for the general problem and demonstrate its ability to reach optimality with instances from the human protein interaction network.

Conclusion

Our results demonstrate that in contrast to most connectivity problems studied in computational biology, accounting for multiplicity of biological conditions adds considerable complexity, which we propose to address with a new solver. Importantly, our results extend to several network connectivity problems that are commonly used in computational biology, such as Prize-Collecting Steiner Tree, and provide insight into the theoretical guarantees for their applications in a multiple condition setting.

Availability

Our solver for the general condition Steiner network problem is available at https://github.com/YosefLab/condition_connectivity_problems
Delta activity encodes taste information in the human brain
Authors: Wallroth Raphael , Ohla Kathrin
Published: April 2018

The categorization of food via sensing nutrients or toxins is crucial to the survival of any organism. On ingestion, rapid responses within the gustatory system are required to identify the oral stimulus to guide immediate behaviour (swallowing or expulsion). The way in which the human brain accomplishes this task has so far remained unclear. Using multivariate analysis of 64-channel scalp EEG recordings obtained from 16 volunteers during tasting salty, sweet, sour, or bitter solutions, we found that activity in the delta-frequency range (1-4 Hz; delta power and phase) has information about taste identity in the human brain, with discriminable response patterns at the single-trial level within 130 ms of tasting. Importantly, the latencies of these response patterns predicted the point in time at which participants indicated detection of a taste by pressing a button. Furthermore, taste pattern discrimination was independent of motor-related activation and other taste features such as intensity and valence. On comparison with our previous findings from a passive (delayed) taste-discrimination task (Crouzet et al., 2015), taste-specific neural representations emerged earlier during this active (speeded) taste-detection task, suggesting a goal-dependent flexibility in gustatory response coding. Together, these findings provide the first evidence of a role of delta activity in taste-information coding in humans. Crucially, these neuronal response patterns can be linked to the speed of simple gustatory perceptual decisions, a vital performance index of nutrient sensing.
Mathematical and ecological traits of above and belowground biomass production of beech (Fagus silvatica L.) trees growing in pure even-aged stands in north-east France
Authors: Goff Noël Le , Ottorini Jean-Marc
Published: April 2018

Tree biomass and biomass increment equations were specially developed in 1996–1997 to study the ecophysiological functioning of an experimental European beech stand, aged about 30 year-old, in the Hesse forest (NE France). In order to extend such a study to beech stands of different age classes, it was necessary to build biomass and biomass increment equations that could be used for any age; we call them generalized biomass equations.

To build such generalized equations, trees were sampled in different forest plots covering the whole age range. Moreover, in each plot, several trees were chosen to represent the different crown classes (from dominant to suppressed). Sampled trees were felled down and the root system excavated for a sub-sample of trees, for biomass analysis by separating the main compartments of the above and belowground tree parts. When it was not possible to measure the total biomass of a given tree compartment (large trees), wood samples were taken in the concerned compartment. Moreover, equations were built to estimate the biomass of the missing parts of the root system and branch compartments that were likely to have suffered losses during root excavation and tree felling, respectively. Multivariate linear and non-linear models including possible random effects were tested to represent the biomass and biomass increment variations of each tree compartment and of their aggregation in the above and belowground parts of the tree.

Compatible biomass and biomass increment equations for the different tree compartments and their combination in above and belowground tree parts were developed and fitted, allowing the analysis of the variations of the biomass distribution and allocation with tree age. Stem growth efficiency was also calculated and appeared dependent on tree age and tree social status.

The biomass and biomass increment equations established for beech in this study allow the estimation of the biomass and carbon stocks and fluxes (NPP) for the even-aged beech stands of the Hesse forest, whatever the age of the stand; they could also be used to analyze the effects of different silvicultural treatments on the biomass and carbon stocks and fluxes of beech stands, using the available stand growth and yield models developed for beech in France.
Polygenic adaptation and convergent evolution across both growth and cardiac genetic pathways in African and Asian rainforest hunter-gatherers
Authors: Bergey Christina M. , Lopez Marie , Harrison Genelle F. , Patin Etienne , Cohen Jacob , Quintana-Murci Lluis , Barreiro Luis B. , Perry George H.
Published: April 2018

Different human populations facing similar environmental challenges have sometimes evolved convergent biological adaptations, for example hypoxia resistance at high altitudes and depigmented skin in northern latitudes on separate continents. The pygmy phenotype (small adult body size), a characteristic of hunter-gatherer populations inhabiting both African and Asian tropical rainforests, is often highlighted as another case of convergent adaptation in humans. However, the degree to which phenotypic convergence in this polygenic trait is due to convergent vs. population-specific genetic changes is unknown. To address this question, we analyzed high-coverage sequence data from the protein-coding portion of the genomes (exomes) of two pairs of populations, Batwa rainforest hunter-gatherers and neighboring Bakiga agriculturalists from Uganda, and Andamanese rainforest hunter-gatherers (Jarawa and Onge) and Brahmin agriculturalists from India. We observed signatures of convergent positive selection between the Batwa and Andamanese rainforest hunter-gatherers across the set of genes with annotated ‘growth factor binding’ functions (p< 0.001). Unexpectedly, for the rainforest groups we also observed convergent and population-specific signatures of positive selection in pathways related to cardiac development (e.g. ‘cardiac muscle tissue development’;p= 0.001). We hypothesize that the growth hormone sub-responsiveness likely underlying the pygmy phenotype may have led to compensatory changes in cardiac pathways, in which this hormone also plays an essential role. Importantly, in the agriculturalist populations we did not observe similar patterns of positive selection on sets of genes associated with either growth or cardiac development, indicating that our results most likely reflect a history of convergent adaptation to the similar ecology of rainforest hunter-gatherers rather than a more common or general evolutionary pattern for human populations.
Predicting influenza H3N2 vaccine efficacy from evolution of the dominant epitope
Authors: Bonomo Melia E. , Deem Michael W.
Published: April 2018

We predict vaccine efficacy with a measure of antigenic distance between influenza A(H3N2) and candidate vaccine viruses based on amino acid substitutions in the dominant epitopes. In 2016-2017, our model predicts 19% efficacy compared to 20% observed. This tool assists candidate vaccine selection by predicting human protection against circulating strains.

40-word summary of main point

Our pepitope model predicts the ability of the influenza vaccine to reduce the A(H3N2) disease attack rate, with an r^2=0.77. This fast, sequence-based method compliments strain-to-strain antigenic comparisons from ferret models and provides antigenic comparisons for all circulating sequences.
Monitoring Anti-Pythium insidiosum IgG Antibodies and (1->3)-β-D-Glucan in Vascular Pythiosis
Authors: Worasilchai Navaporn , Permpalung Nitipong , Chongsathidkiet Pakawat , Leelahavanichkul Asada , Mendoza Alberto Leonel , Palaga Tanapat , Reantragoon Rangsima , Finkelman Malcolm , Sutcharitchan Pranee , Chindamporn Ariya
Published: April 2018

Background

Despite aggressive treatment, vascular pythiosis has a mortality rate of 40%. This is due to the delay in diagnosis and lack of effective monitoring tools. To overcome this drawback, serum beta-D-glucan (BG) and P. insidiosum specific antibody (Pi-Ab) were examined as potential monitoring markers in vascular pythiosis.

Methods

A prospective cohort study of vascular pythiosis patients was carried on during January 2010-July 2016. Clinical information and blood samples were collected and evaluated by the BG and Pi-Ab assays. Linear mixed effect models were used to compare BG and Pi-Ab levels. The in vitro susceptibility test was performed in all P. insidiosum isolates from culture positive cases.

Results

A total of 50 patients were enrolled; 45 survived and 5 died during follow-up. The survivors had a significantly shorter time to medical care (p<0.0001) and a significantly shorter waiting time to the first surgery (p<0.0001). There were no differences in BG levels among the groups at diagnosis (p=0.17); however, BG levels among survivors were significantly lower than the deceased group at 0.5 months (p<0.0001) and became undetectable after 3 months. Survivors were able to maintain ELISA value (EV) of Pi-Ab above 8, whereas EV among deceased patients was less than 4. In vitro susceptibility results revealed no synergistic effects between itraconazole and terbinafine.

Conclusions

This study showed that BG and Pi-Ab were potentially valuable markers to monitor the disease after treatment initiation. An unchanged BG level at 2 weeks after surgery should prompt an evaluation for residual disease.
An important role for periplasmic storage inPseudomonas aeruginosacopper homeostasis revealed by a combined experimental and computational modeling study
Authors: Parmar Jignesh H. , Quintana Julia , Ramírez David , Laubenbacher Reinhard , Argüello José M. , Mendes Pedro
Published: April 2018

Biological systems require precise copper homeostasis enabling metallation of cuproproteins while preventing metal toxicity. In bacteria, sensing, transport and storage molecules act in coordination to fulfill these roles. However, there is not yet a kinetic schema explaining the system integration. Here, we report a model emerging from experimental and computational approaches that describes the dynamics of copper distribution inPseudomonas aeruginosa. Based on copper uptake experiments, a minimal kinetic model describes well the copper distribution in the wild type bacteria but is unable to explain the behavior of the mutant strain lacking CopA1, a key Cu+efflux ATPase. The model was expanded through an iterative hypothesis-driven approach, arriving to a mechanism that considers the induction of compartmental pools and the parallel function of CopA and Cus efflux systems. Model simulations support the presence of a periplasmic copper storage with a crucial role under dyshomeostasis conditions inP. aeruginosa. Importantly, the model predicts not only the interplay of periplasmic and cytoplasmic pools but also the existence of a threshold in the concentration of external copper beyond which cells lose their ability to control copper levels.
Nicotinic modulation of hierarchal inhibitory control over prefrontal cortex resting state dynamics: modeling of genetic modification and schizophreniarelated pathology
Authors: Rooy Marie , Koukouli Fani , Maskos Uwe , Gutkin Boris
Published: April 2018

Nicotinic acetylcholine receptors (nAChRs) strongly modulate the cholinergic drive to a hierarchy of inhibitory neurons in the superficial layers of the PFC, critical to cognitive processes. Genetic deletion of various types of nAChRs, located on specific interneurons, impacts the properties of ultra-slow transitions between high and low activity states (H-states and L-states, respectively), recorded in mice during quiet wakefulness. In addition, recent data indicate that a genetic mutation of the α5 nAChR subunit located on vasoactive intestinal polypeptide (VIP) inhibitory neurons, the rs16969968 single nucleotide polymorphism (α5 SNP), appears to be responsible for “hypofrontality” observed in schizophrenia. Chronic nicotine application to α5 SNP mice restores neural activity to control levels. Using firing rate models of hierarchically organized neural populations, we showed that the change of activity patterns recorded in the genetically modified mice can be explained by a change of activity state stability, differentially modulated by cholinergic inputs to parvalbumin (PV), somatostatin (SOM) or VIP inhibitory populations. A change in amplitude, but not duration of H-states fully account for the lowered pyramidal (PYR) firing rates recorded in α5 SNP mice. We demonstrate that desensitization and upregulation of β2 nAChRs located on SOM interneurons, but not activation of α5 nAChRs located on VIP interneurons, by chronic nicotine application could account for activity normalization recorded in α5 SNP mice. The model implies that subsequent nicotine withdrawal should lead to PYR activity depression more severe than the original hypofrontality caused by SNP mutation.
Why talented athletes drop out from sport? The Portuguese and Czech case
Authors: Silva Dias Teresa , Novotná Katerina , Oliveira Helder Zimmermann , Azevedo Carlos , Corte-Real Nuno , Slepička Pavel , Fonseca António Manuel
Published: April 2018

Purpose

The purpose of this paper is to perceive the perspective of Portuguese and Czech’ talented athletes regarding: the main reasons pointed to drop out of sport, putting into analysis motivational factors; the conciliation of School and Sport, and how the organization of schools and sports contexts are articulated in relation to the training and promotion of students, athletes and citizens; and the contributions (positive/negative) of sports to daily life and society.

Design/methodology/approach

This study uses a qualitative approach to interview eight talented athletes from different sports that had to drop out the practice of sport and explores their narratives regarding experiences and the relational dynamics between sports contexts and schools.

Findings

Athletes identify factors that led to drop out: the coach profile or the methodology and dynamics of practicing/training; time consuming; and the impossibility of reconciling sports with school/job. Athletes can identify the sport’s culture, self-development and health being as positive contributions of sports, whereas injuries were referred as the main negative factor of sport. As proposal of changes, athletes referred to the need of a more professional organization of the sport contexts and to more proximity between school policies and sport policies allowing conciliating both.

Research limitations/implications

One limitation that could be pointed to this research is the difference between the Czech and Portuguese socio-cultural and political situation, not only in the concept and organization of sports activities (since scholar years) but also in the general society. This difference could have more visibility when interpreting the data that led to this fact referred above.

Practical implications

It is recommended a more proximity relationship between researchers and the contexts of practice (sport contexts) being that it is important that these contexts should have feedback from the investigations carried out. Only in this way coaches, federations and confederations can be aware of the motivational factors that lead to talented athletes drop out, and make a greater investment in initial formation of the coaches and propose policies that try to establish partnerships with schools or professional contexts which could help the management of athletes’ times outside of sport.

Originality/value

Departing from the athletes’ feelings, concerns and motivations related to sport and the reasons that led to their drop out, we argue for the definition of public policies, in both countries, that promote non-discrimination of young people who wish to maintain a path linked to sports in articulation with other areas of their lives.
A novel method to solve sustainable economic power loading dispatch problem
Authors: Li Lingling , Yang Yanfang , Tseng Ming-Lang , Wang Ching-Hsin , Lim Ming K.
Published: April 2018

Purpose

The purpose of this paper is to deal with the economic requirements of power system loading dispatch and reduce the fuel cost of generation units. In order to optimize the scheduling of power load, an improved chicken swarm optimization (ICSO) is proposed to be adopted, for solving economic load dispatch (ELD) problem.

Design/methodology/approach

The ICSO increased the self-foraging factor to the chicks whose activities were the highest. And the evolutionary operations of chicks capturing the rooster food were increased. Therefore, these helped the ICSO to jump out of the local extreme traps and obtain the global optimal solution. In this study, the generation capacity of the generation unit is regarded as a variable, and the fuel cost is regarded as the objective function. The particle swarm optimization (PSO), chicken swarm optimization (CSO), and ICSO were used to optimize the fuel cost of three different test systems.

Findings

The result showed that the convergence speed, global search ability, and total fuel cost of the ICSO were better than those of PSO and CSO under different test systems. The non-linearity of the input and output of the generating unit satisfied the equality constraints; the average ratio of the optimal solution obtained by PSO, CSO, and ICSO was 1:0.999994:0.999988. The result also presented the equality and inequality constraints; the average ratio of the optimal solution was 1:0.997200:0.996033. The third test system took the non-linearity of the input and output of the generating unit that satisfied both equality and inequality constraints; the average ratio was 1:0.995968:0.993564.

Practical implications

This study realizes the whole fuel cost minimization in which various types of intelligent algorithms have been applied to the field of load economic scheduling. With the continuous evolution of intelligent algorithms, they save a lot of fuel cost for the ELD problem.

Originality/value

The ICSO is applied to solve the ELD problem. The quality of the optimal solution and the convergence speed of ICSO are better than that of CSO and PSO. Compared with PSO and CSO, ICSO can dispatch the generator more reasonably, thus saving the fuel cost. This will help the power sector to achieve greater economic benefits. Hence, the ICSO has good performance and significant effectiveness in solving the ELD problem.
Process of innovation knowledge increase in supply chain network from the perspective of sustainable development
Authors: Zhang Dan , Wang Ching-Hsin , Zheng Dengpan , Yu Xianyun
Published: April 2018

Purpose

The purpose of this paper is to extend prior supply chain research by describing the process of innovation knowledge increase in supply chain network. More specifically, this study investigates the role of network density, and views the knowledge increase as the process of knowledge diffusion and knowledge innovation.

Design/methodology/approach

A multi-agent model, which demonstrates the process of knowledge increase in supply chain network, was established, and simulated by using NetLogo simulation platform.

Findings

The results indicate that the network density will promote the knowledge increase of the supply chain when it is high or low. In the meantime, these results show that the inhibition of knowledge diffusion and knowledge innovation will appear when network density is moderate.

Originality/value

Although previous research has identified the importance of knowledge increase in promoting sustainable development of supply chain, far less attention was given to the study of the effect of network structure on the knowledge increase in supply chain. This study thus fulfills the research gap by providing a description of the process of knowledge increase with the consideration of network density. The conclusion is of great significance for the choice of network density for sustainable development of supply chain.
Buying decision in the marketing ofSharialife insurance (evidence from Indonesia)
Authors: Amron Amron , Usman Usman , Mursid Ali
Published: April 2018

Purpose

The purpose of this study is to examine the effect of satisfaction (SAT) and trust (TRS) on word of mouth (WOM) and buying decision (BD) forSharialife insurance in the Muslim society of Indonesia.

Design/methodology/approach

The research design was taken from 386 Muslim customers who heldSharialife insurance policies using the approach of purposive sampling in four cities in Indonesia, namely, Jakarta, Surabaya, Makassar and Medan. The hypothesis testing used structural equation modeling.

Findings

The research results show SAT and TRS have effects on WOM. Moreover, WOM has a significant effect on the BD of the customers of theSharialife insurance product.

Research limitations/implications

This study focused only BD of customers who boughtSharialife insurance products, so the results cannot be generalized to other types ofShariainsurance. Therefore, future research could consider otherShariainsurance products, such asShariageneral insurance.

Practical implications

In relation to the testing of SAT and TRS on WOM, this study examined the influence of the two variables on WOM and BD. This study can serve as reference forSharialife insurance companies when formulating promotion strategy.

Originality/value

This study justified the strong association between SAT and TRS for WOM and BD inSharialife insurance in an integrated way.
The effect of socio-demographic variables and travel characteristics on motivation of Muslim family tourists in Malaysia
Authors: Aziz Yuhanis Abdul , Hussin Siti Rahayu , Nezakati Hossein , Raja Yusof Raja Nerina , Hashim Haslinda
Published: April 2018

Purpose

This paper aims to investigate the socio-demographic variables that affect the motivation of Muslim tourists in Malaysia, and to examine the travel characteristics factors that affect the motivation in decision making of Muslim tourists travelling to Malaysia.

Design/methodology/approach

The study surveys questionnaires for data collection. Convenience sampling technique was used on the selected sample. The study was conducted in Malaysia, where the target respondents included Muslim family tourists with ages ranging from 18 to 64 years.

Findings

The findings show that motivation differs significantly among different levels of the socio-demographic characteristics except for gender and income. The result also reported that a majority of tourists’ travel behaviour was significantly different unless when it comes to seeking accommodation. Results also revealed a tendency for long holiday stays among Muslim tourists in Malaysia.

Research limitations/implications

In this study, the examination of motivation on the Muslim family tourists has provided significant influence in managing the family tourist experience. On the other hand, most previous studies have shown that motivation is positively guided by general “push and pull” factors. However, this research demonstrates that components such family financial income and age of respondents has an effect on Muslim family tourists’ motivation, thus justifying the experience effect.

Practical implications

It is crucial for the service provider and destination management organizations to differentiate their products and services so that the packages and experience will be more meaningful.

Social implications

Destination packages should be appropriately designed and positioned in the target markets to meet the needs and wants of different Muslim family groups. Communication should emphasize not only the most distinctive characteristics but also the most suitable holiday packages that the family tourist can afford to pay. This would assist the family in the decision-making process and choice processes and facilitate the family’s expectation.

Originality/value

This research paper related to Islamic tourism marketing which can be used to formulate appropriate marketing strategies, build a viable market segment and design practical marketing strategies to attract potential Muslims travellers.
What potentials does Islamic micro-credit have?
Authors: El Ebrashi Raghda , Salem Rania , El Kayaly Dina , El-Bassiouny Noha
Published: April 2018

Purpose

This paper aims to investigate the role of demographics and sector type in determining consumer preferences of Islamic micro-credit products, namely,MusharkaandMurabha, versus conventional micro-credit financing in Egypt.

Design/methodology/approach

This research is a quantitative study that uses surveys on 1,125 current micro-credit consumers in Cairo and Upper Egypt using multi-staged cluster sampling technique. Descriptive and inferential analyses were used to explain results.

Findings

The study revealed the potential ofMusharkamode of financing among micro-credit borrowers in Egypt, specifically in the manufacturing sector, followed by the trade sector. Although previous researches showed correlations between income, age and other demographic factors with consumer financing choices, the current research indicated no significance for consumer demographics in determining preferences of Islamic micro-credit contracts in Egypt. However, the sector type showed high potential in determining consumer choices of Islamic micro-credit contracts.

Research limitations/implications

This paper advances knowledge in the domain of consumer behavior, specifically in bottom of the pyramid and subsistence markets that are under researched.

Practical implications

The results highlighted are important for micro-finance institutions, NGOs and policy makers, as they delve deeper into the consumer preferences for Islamic financial products and attempt to present innovative solutions toward poverty eradication.

Originality/value

This research is one of the few attempts to study and explain consumer preferences toward Islamic micro-credit products in Egypt, and the role of sectors in determining consumer choices for specific Islamic micro-credit contracts.
An automatic and optimal selection of parts orientation in additive manufacturing
Authors: Al-Ahmari Abdurahman Mushabab , Abdulhameed Osama , Khan Awais Ahmad
Published: April 2018

Purpose

In additive manufacturing processes such as stereolithography and fused deposition modeling, optimal part orientation is pivotal in improving the quality of the part. This paper aims to propose an automatic and optimal part orientation system to improve part quality/accuracy in additive manufacturing, which minimizes the production time and hence reduces the cost of product.

Design/methodology/approach

The developed system reads STEP AP 203 E2 file from CATIA V5 and generates data extraction output file by extracting the relevant geometrical and topological data using an object-oriented approach. Afterwards, the algorithms and rules are developed to extract and recognize feature faces along with their geometric properties such as face type, face area, parallelism and perpendicularity. The feature data obtained that are used to develop feasible part orientations depend on the maximization of G&DT for all part faces. The automatic slicing is then achieved by creating slicing file using CATVBA editor inside CATIA V5.

Findings

After slicing, output data are exported in Excel data sheet to calculate the total additive volume of the part. The building time of the part is then calculated on the basis of machine parameters, part geometry, part height, layer thickness and amount of support volume needed to build the part. The optimal orientation of the part is achieved by maximization of G&DT value and minimization of production time. The proposed methodology is tested using an illustrative example.

Originality/value

Although lot of approaches have been discussed in the literature, automation of setup planning/orientation of the part in additive manufacturing is not fully attained. Therefore, the article focuses on the automation of setup planning by adding automatic feature extraction and recognition module along with the automatic slicing during setup planning. Moreover, the significance of adding feature extraction and recognition module is to achieve best accuracy for form feature faces and hence reduction in post processing machining/finishing operations.
Employee engagement: what’s your strategy?
Authors: Matthews Geoffrey
Published: April 2018

Purpose

This paper aims to explore some of the reasons why employee engagement activities may lack effectiveness and sets out some proposals as to what organizations can do to take a more strategic approach in future.

Design/methodology/approach

This paper is based on a research of current practices in organizations combined with the author’s experience and views on employee engagement activities.

Findings

The paper highlights the limitations of approaches in many organizations and proposes a series of strategic choices that organizations need to make to help ensure their future approach is more effective.

Originality/value

This paper sets out a model that can be used by HR executives with business leaders to decide on a clear engagement strategy for the future.