bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of a single mediastinal drain through the abdominal wall after esophagectomy
Authors: Zheng Yan , Li Yin , Liu Xianben , Zhang Ruixiang , Wang Zongfei , Sun Haibo
Published: November 2018

This study evaluated the safety and effectiveness of a single mediastinal drainage tube in the thoracic and abdominal cavity after minimally invasive esophagectomy (MIE). This study was undertaken to determine if the procedure could be included in a fast-track surgery program for resectable esophageal carcinoma (EC).

From June 17 to November 30, 2015, clinical data for 78 eligible patients who had undergone a fast-track surgery program and MIE were retrospectively analyzed. Twenty-eight patients had a chest tube and mediastinal drainage tube. Thirty-four patients had only a mediastinal drainage tube through the intercostal space. The remaining 30 patients had a single mediastinal drainage tube in the thoracic and abdominal cavity through the abdominal wall. The complication rates and pain scores for each of the groups were compared. The statistical calculations were performed using SPSS 17.0 for Windows (SPSS Inc., Chicago, IL). The quantitative data among the groups were compared using 1-way analysis of variance (ANOVA). The Chi-square, Mann–Whitney U and Fisher exact tests were used for qualitative data analysis.

There were no significant differences in the anastomotic leak rates, postoperative days and total complication rates (P = .861). The lowest visual analog scale (VAS) scores of the drainage tubes were observed in the group with a single mediastinal drain through the abdominal wall (P <.001).

The results of this study suggested that a single mediastinal drainage tube in the thoracic and abdominal cavity after MIE may be safe and efficient. This clinical practice is a part of our fast-track surgery program.
Effect of prophylactic palonosetron and sugammadex on postoperative nausea and vomiting in patients undergoing microvascular decompression under propofol-maintained anesthesia
Authors: Kang Hee Yong , Park Sung Wook , Lee Sangho , Jeon Jong-Mi , Oh In Duk , Choi Jeong-Hyun
Published: November 2018

Microvascular decompression (MVD) is associated with a particularly high risk of postoperative nausea and vomiting (PONV) among craniotomy patients. However, there is no information regarding the effect of prophylactic palonosetron and sugammadex on PONV in patients undergoing MVD under propofol-maintained anesthesia.

Medical records of 274 adults who had undergone MVD under propofol-maintained anesthesia were reviewed. Patients were classified into 4 groups, based on the reversal agent used (sugammadex/pyridostigmine) and whether or not prophylactic palonosetron was used. The PONV incidence and risk factors were analyzed according to the use of these agents.

The overall incidence of PONV was 30.7% during the first 24 hours postoperatively. The incidence of PONV was lower in the group using combination of prophylactic palonosetron and sugammadex (19.3%) compared with the group not using both agents (37.2%). The combined use of the prophylactic palonosetron and sugammadex was identified as a factor affecting the occurrence of PONV in both univariable (OR = 0.40, 95% CI: 0.21–0.77, P = .006) and multivariable (OR = 0.38, 95% CI: 0.20–0.75, P = .005) logistic regression analyses. In multivariable logistic regression analysis, female sex was also significant independent risk factor in PONV (OR = 2.62, 95% CI: 1.35–5.08, P = .004).

In this retrospective observational study, the combined use of prophylactic palonosetron before anesthetic induction and sugammadex as a reversal of neuromuscular blockade are associated with a reduction in the incidence of PONV in patients undergoing MVD under propofol-maintained anesthesia.
The associations among Helicobacter pylori infection, white blood cell count and nonalcoholic fatty liver disease in a large Chinese population
Authors: Yu Ying-ying , Cai Jian-ting , Song Zhen-ya , Tong Yu-ling , Wang Jing-hua
Published: November 2018

Reported relationships among Helicobacter pylori infection, white blood cell (WBC) count and nonalcoholic fatty liver disease (NAFLD) are inconsistent and controversial. We, therefore, conducted a cross-sectional study to investigate the associations among the presence of NAFLD, WBC count and H pylori infection, as diagnosed using the 13C-urea breath test (UBT).

This study included 20,389 subjects enrolled at the International Health Care Center of the Second Affiliated Hospital of the Zhejiang University School of Medicine from January 2015 to December 2015. All participants underwent a 13C-UBT for the diagnosis of H pylori infection and ultrasonography for NAFLD as well as a blood test to determine WBC count. Multivariate logistic regression was then performed to evaluate the relationship among H pylori infection, WBC count and NAFLD.

H pylori infection was detected in 38.49% (7,848/20,389) of the subjects via the UBT, and NAFLD was present in 37.24% (7,592/20,389) of the subjects. The prevalence of H pylori infection was higher in the NAFLD group than in the control group (41.25% vs 36.85%, P <.001). Significant differences were found between various WBC quartiles and H pylori infection, age, gender, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), high-sensitivity C-reactive protein (HS-CRP), glycosylated hemoglobin (HbA1c), triglyceride (TG), low-density lipoprotein (LDL-C), fasting blood glucose (FPG), homeostasis model assessment of insulin resistance (HOMA-IR), and smoking. Multivariate logistic regression revealed that the combination of H pylori infection and WBC count (odds ratio [OR] = 1.067, 95% confidence interval [CI]: 1.014, 1.093; P = .007; OR = 1.165, 95% CI: 1.023, 1.488; P <.001; OR = 1.183, 95% CI: 1.085, 1.559; P <.001, respectively) was positively associated with NAFLD.

H pylori infection and WBC count may contribute to the pathogenesis of NAFLD.
Dose-dependent effect of propranolol on the hemodynamic response in cirrhotic patients with gastroesophageal varices
Authors: Zhang Feng , Xu Hui , Chen Min , Zhang Ming , Xiao Jiangqiang , Wang Yi , He Qibin , Zhang Wei , Yin Xiaochun , Zou Xiaoping , Zhuge Yuzheng
Published: November 2018

Objective

Propranolol is always titrated to the maximum tolerated dose to prevent gastroesophageal variceal bleeding. However, some patients do not achieve a hemodynamic response and experience more intolerance and discontinuation. This study evaluated the dose-dependent effect of propranolol on hemodynamic response and tolerance in cirrhotic patients.

Patients and methods

This retrospective study included 95 consecutive patients recruited from our prospective database. After hepatic venous pressure gradient measurement, patients received propranolol 10 mg, twice daily increased 10 mg daily until to 80 or 120 mg/day. Secondary hepatic venous pressure gradient was also measured. For nonresponders at 80 mg/day, propranolol was titrated to 120 mg/day.

Results

For 58 patients, propranolol was titrated to 80 mg/day, whereas for 37 patients, it was titrated to 120 mg/day. Hemodynamic response was similar in both groups (50 vs. 54.1%, P=0.700). Eighteen of the 29 nonresponders at propranolol 80 mg/day received a dose of 120 mg/day. Two patients achieved a hemodynamic response, but two could not tolerate the dose. Nine (15.5%) patients achieved the target dose of propranolol at 80 mg/day, whereas 16 (43.2%) patients at 120 mg/day achieved this (P=0.003). The difference in patients achieving the target dose between responders and nonresponders was not significant (14 vs. 14, P=0.642). Reduction or discontinuation was required by two (6.9%) patients using 80 mg/day propranolol and six (30%) patients using 120 mg/day propranolol (P=0.032).

Conclusion

There is no dose-dependent effect of 80–120 mg/day of propranolol on the hemodynamic response in cirrhotic patients with gastroesophageal varices. This indicates that low-dose propranolol below the target dose might lead to a considerable hemodynamic response and is much safer and well tolerated.
Impact of Antiretroviral Drugs on Fracture Risk in HIV-Infected Individuals: A Case–Control Study Nested Within the French Hospital Database on HIV (FHDH-ANRS CO4)
Authors: Costagliola Dominique , Potard Valérie , Lang Sylvie , Abgrall Sophie , Duvivier Claudine , Fischer Hugues , Joly Véronique , Lacombe Jean-Marc , Valantin Marc-Antoine , Mary-Krause Murielle , Rozenberg Sylvie ,   on behalf of FHDH ANRS CO4
Published: November 2018

Background:

HIV-infected patients have lower bone mineral density and a higher incidence of fractures than the general population of the same age and sex. To assess the impact of antiretroviral (ARV) drugs exposure on the risk of osteoporotic fractures, we conducted a nested case–control study.

Methods:

Cases were individuals enrolled while ARV-naive, with a first prospectively recorded fracture between 2000 and 2010. Controls were randomly selected after matching for sex, age (±3 years), period of HIV diagnosis (<1997/≥1997), and clinical center. The risk of fracture was analyzed with conditional logistic regression models, using different ways to model ARV exposure. All exposure variables and potential confounders were included in multivariable models.

Results:

Among 861 reviewed cases, 261 fractures were osteoporotic and 254 of cases were matched to at least one control (376 controls). The median year of fracture diagnosis was 2007 (interquartile range 2004–2009): 49% of patients had been exposed to tenofovir disoproxil fumarate (TDF) and 82% to protease inhibitors (PIs). After taking into account the transmission group, AIDS status, geographic origin, body mass index, current smoking status, alcohol consumption, exposure to systemic glucocorticoids, and the period of enrollment, there was no association between the risk of fracture and exposure to TDF [odds ratio for cumulative exposure: 1.04 (0.86–1.27), similar results for ever-exposed subjects], to nucleoside reverse transcriptase inhibitors, or to PIs [odds ratio for cumulative PI exposure: 1.02 (0.92–1.12)].

Conclusions:

We found no evidence of an excess risk of fracture after exposure to TDF or PIs. This has important implications for the debate concerning tenofovir alafenamide versus generic TDF.
Medical Intensive Care Unit Admission Among Patients With and Without HIV, Hepatitis C Virus, and Alcohol-Related Diagnoses in the United States: A National, Retrospective Cohort Study, 1997–2014
Authors: Rentsch Christopher T. , Tate Janet P. , Steel Tessa , Butt Adeel A. , Gibert Cynthia L. , Huang Laurence , Pisani Margaret , Soo Hoo Guy W. , Crystal Stephen , Rodriguez-Barradas Maria C. , Brown Sheldon T. , Freiberg Matthew S. , Graber Christopher J. , Kim Joon W. , Rimland David , Justice Amy C. , Fiellin David A. , Crothers Kristina A. , Akgün Kathleen M.
Published: November 2018

Background:

HIV, hepatitis C virus (HCV), and alcohol-related diagnoses (ARD) independently contribute increased risk of all-cause hospitalization. We sought to determine annual medical intensive care unit (MICU) admission rates and relative risk of MICU admission between 1997 and 2014 among people with and without HIV, HCV, and ARD, using data from the largest HIV and HCV care provider in the United States.

Setting:

Veterans Health Administration.

Methods:

Annual MICU admission rates were calculated among 155,550 patients in the Veterans Aging Cohort Study by HIV, HCV, and ARD status. Adjusted rate ratios and 95% confidence intervals (CIs) were estimated with Poisson regression. Significance of trends in age-adjusted admission rates were tested with generalized linear regression. Models were stratified by calendar period to identify shifts in MICU admission risk over time.

Results:

Compared to HIV−/HCV−/ARD− patients, relative risk of MICU admission decreased among HIV-mono-infected patients from 61% (95% CI: 1.56 to 1.65) in 1997–2009% to 21% (95% CI: 1.16 to 1.27) in 2010–2014, increased among HCV-mono-infected patients from 22% (95% CI: 1.16 to 1.29) in 1997–2009% to 54% (95% CI: 1.43 to 1.67) in 2010–2014, and remained consistent among patients with ARD only at 46% (95% CI: 1.42 to 1.50). MICU admission rates decreased by 48% among HCV-uninfected patients (P-trend <0.0001) but did not change among HCV+ patients (P-trend = 0.34).

Conclusion:

HCV infection and ARD remain key contributors to MICU admission risk. The impact of each of these conditions could be mitigated with combination of treatment of HIV, HCV, and interventions targeting unhealthy alcohol use.
Better Outcomes Among HIV-Infected Rwandan Children 18–60 Months of Age After the Implementation of “Treat All”
Authors: Arpadi Stephen , Lamb Matthew , Nzeyimana Isaie N. , Vandebriel Greet , Anyalechi Gloria , Wong Marcia , Smith Rebecca , Rivadeneira Emilia D. , Kayirangwa Eugenie , Malamba Samuel S. , Musoni Canisious , Koumans Emilia H. , Braaten Mollie , Nsanzimana Sabin
Published: November 2018

Background:

In 2012, Rwanda introduced a Treat All approach for HIV-infected children younger than 5 years. We compared antiretroviral therapy (ART) initiation, outcomes, and retention, before and after this change.

Methods:

We conducted a retrospective study of children enrolled into care between June 2009 and December 2011 [Before Treat All (BTA) cohort] and between July 2012 and April 2015 [Treat All (TA) cohort].

Setting:

Medical records of a nationally representative sample were abstracted for all eligible aged 18–60 months from 100 Rwandan public health facilities.

Results:

We abstracted 374 medical records: 227 in the BTA and 147 in the TA cohorts. Mean (SD) age at enrollment was [3 years (1.1)]. Among BTA, 59% initiated ART within 1 year, vs. 89% in the TA cohort. Median time to ART initiation was 68 days (interquartile range 14–494) for BTA and 9 days (interquartile range 0–28) for TA (P < 0.0001), with 9 (5%) undergoing same-day initiation in BTA compared with 50 (37%) in TA (P < 0.0001). Before ART initiation, 59% in the BTA reported at least one health condition compared with 35% in the TA cohort (P < 0.0001). Although overall loss to follow-up was similar between cohorts (BTA: 13%, TA: 8%, P = 0.18), loss to follow-up before ART was significantly higher in the BTA (8%) compared with the TA cohort (2%) (P = 0.02).

Conclusions:

Nearly 90% of Rwandan children started on ART within 1 year of enrollment, most within 1 month, with greater than 90% retention after implementation of TA. TA was also associated with fewer morbidities.
Efficacy and Safety of Tenofovir Disoproxil Fumarate Versus Low-Dose Stavudine Over 96 Weeks: A Multicountry Randomized, Noninferiority Trial
Authors: Venter Willem Daniel Francois , Kambugu Andrew , Chersich Matthew F. , Becker Stephen , Hill Andrew , Arulappan Natasha , Moorhouse Michelle , Majam Mohammed , Akpomiemie Godspower , Sokhela Simiso , Poongulali Selvamuthu , Feldman Charles , Duncombe Chris , Ripin David H. Brown , Vos Alinda , Kumarasamy Nagalingeswaran
Published: November 2018

Background:

Reducing doses of antiretroviral drugs, including stavudine (d4T), may lower toxicity, while preserving efficacy. There are substantial concerns about renal and bone toxicities of tenofovir disoproxil fumarate (TDF).

Setting:

HIV-1–infected treatment-naive adults in India, South Africa, and Uganda.

Methods:

A phase-4, 96-week, randomized, double-blind, noninferiority trial compared d4T 20 mg twice daily and TDF, taken in combination with lamivudine (3TC) and efavirenz (EFV). The primary endpoint was the proportion of participants with HIV-1 RNA <50 copies per milliliter at 48 weeks. Adverse events assessments included measures of bone density and body fat. The trial is registered on Clinicaltrials.gov (NCT02670772).

Results:

Between 2012 and 2014, 536 participants were recruited per arm. At week 96, trial completion rates were 75.7% with d4T/3TC/EFV (n = 406) and 82.1% with TDF/3TC/EFV (n = 440, P = 0.011). Noncompletion was largely due to virological failure [6.2% (33) with d4T/3TC/EFV versus 5.4% (29) with TDF/3TC/EFV; P = 0.60]. For the primary endpoint, d4T/3TC/EFV was noninferior to TDF/3TC/EFV (79.3%, 425/536 versus 80.8% 433/536; difference = −1.49%, 95% CI: −6.3 to 3.3; P < 0.001). Drug-related adverse event discontinuations were higher with d4T (6.7%, 36), than TDF (1.1%, 6; P < 0.001). Lipodystrophy was more common with d4T (5.6%, 30) than TDF (0.2%, 1; P < 0.001). Creatinine clearance increased in both arms, by 18.1 mL/min in the d4T arm and 14.2 mL/min with TDF (P = 0.03). Hip bone density measures, however, showed greater loss with TDF.

Conclusions:

Low-dose d4T combined with 3TC/EFV demonstrated noninferior virological efficacy compared with TDF/3TC/EFV, but mitochondrial toxicity remained high. Little renal toxicity occurred in either arm. Implications of bone mineral density changes with TDF warrant investigation.
Intraspecific size variation in planktonic foraminifera cannot be consistently predicted by the environment
Authors: Rillo Marina C. , Miller C. Giles , Kucera Michal , Ezard Thomas H. G.
Published: November 2018

The size structure of plankton communities is an important determinant of their functions in marine ecosystems. However, few studies have quantified how organism size varies within species across space. Using a recently-digitised museum collection, we investigate at high intraspecific resolution how planktonic foraminifera, an important microfossil group, vary in size across the tropical and subtropical oceans of the world. We measured 3799 individuals of nine species in 53 seafloor sediments and analysed potential size biases in the museum collection. For each site, we obtained corresponding local values of mean annual sea-surface temperature (SST), net primary productivity (NPP), and relative abundance of each species. Given former studies, we expected species to reach largest shell sizes under optimal environmental conditions. At species level, we find the expected pattern; however, at population level, species greatly differ in how much size variation is explained by SST, NPP and/or relative abundance. While some species show a high predictability of size variation given one single variable (Trilobatus sacculifer, Globigerinella siphonifera, Pulleniatina obliquiloculata, Globorotalia truncatulinoides), other species showed either weak or no relationships between size and the studied covariates (Globigerinoides ruber, G. conglobatus, Neogloboquadrina dutertrei, G. menardii, Globoconella inflata). By incorporating intraspecific variation and sampling broader geographical ranges compared to previous studies, we conclude that shell size variation in planktonic foraminifera species cannot be consistently predicted by the environment. Our results caution against the general use of size as a proxy for planktonic foraminifera environmental optima, and emphasise the need for more studies analysing their within-species size variation. More generally, our findings show that contrasting results can be obtained when analysing patterns at different organisational levels, and highlights the utility of natural history collections.
WUSCHEL acts as a rheostat on the auxin pathway to maintain apical stem cells inArabidopsis
Authors: Ma Yanfei , Miotk Andrej , Šutiković Zoran , Medzihradszky Anna , Wenzl Christian , Ermakova Olga , Gaillochet Christophe , Forner Joachim , Utan Gözde , Brackmann Klaus , Galvan-Ampudia Carlos S. , Vernoux Teva , Greb Thomas , Lohmann Jan U.
Published: November 2018

To maintain the balance between long-term stem cell self-renewal and differentiation, dynamic signals need to be translated into spatially precise and temporally stable gene expression states. In the apical plant stem cell system, local accumulation of the small, highly mobile phytohormone auxin triggers differentiation while at the same time, pluripotent stem cells are maintained throughout the entire life-cycle. We find that stem cells are resistant to auxin mediated differentiation, but require low levels of signaling for their maintenance. We demonstrate that the WUSCHEL transcription factor confers this behavior by rheostatically controlling the auxin signaling and response pathway. Finally, we show that WUSCHEL acts via regulation of histone acetylation at target loci, including those with functions in the auxin pathway. Our results reveal an important mechanism that allows cells to differentially translate a potent and highly dynamic developmental signal into stable cell behavior with high spatial precision and temporal robustness.
Physical Linkage and Mate Preference Generate Linkage Disequilibrium for Behavioral Isolation in two Parapatric Crickets
Authors: Blankers Thomas , Berdan Emma L. , Hennig R. Matthias , Mayer Frieder
Published: November 2018

Behavioral isolation is a potent barrier to gene flow and a source of striking diversity in the animal kingdom. However, it remains unclear if the linkage disequilibrium (LD) between sex-specific traits required for behavioral isolation results mostly from physical linkage between signal and preference loci or from directional mate preferences. Here, we test this in the field cricketsGryllus rubensandG. texensis. These closely related species diverged with gene flow and have strongly diverged songs and preference functions for the mate calling song rhythm. We map quantitative trait loci for signal and preference traits (pQTL) as well as for gene expression associated with these traits (eQTL). We find strong, positive genetic covariance between song traits and between song and preference. Our results show that this is in part explained by incomplete physical linkage: although both linked pQTL and eQTL couple male and female traits, major effect loci for different traits were never on the same chromosome. We suggest that the finely-tuned, highly divergent preference functions are likely an additional source of LD between male and female traits in this system. Furthermore, pleiotropy of gene expression presents an underappreciated mechanism to link sexually dimorphic phenotypes.
Testing for Hardy-Weinberg Equilibrium in Structured Populations using NGS Data
Authors: Meisner Jonas , Albrechtsen Anders
Published: November 2018

Testing for Hardy-Weinberg Equilibrium (HWE) is a common practice for quality control in genetic studies. Variable sites violating HWE may be identiﬁed as technical errors in the sequencing or genotyping process, or they may be of special evolutionary interest. Large-scale genetic studies based on next-generation sequencing (NGS) methods have become more prevalent as cost is decreasing but these methods are still associated with statistical uncertainty. The large-scale studies usually consist of samples from diverse ancestries that make the existence of some degree of population structure almost inevitable. Precautions are therefore needed when analyzing these datasets, as population structure causes deviations from HWE. Here we propose a method that takes population structure into account in the testing for HWE, such that other factors causing deviations from HWE can be detected. We show the effectiveness of our method in NGS data, as well as in genotype data, for both simulated and real datasets, where the use of genotype likelihoods enables us to model the uncertainty for low-depth sequencing data.
Activation of rod input in a model of retinal degeneration reverses retinal remodeling and induces formation of normal synapses, circuitry and visual signaling in the adult retina
Authors: Wang Tian , Pahlberg Johan , Cafaro Jon , Sampath Alapakkam P. , Field Greg D. , Chen Jeannie
Published: November 2018

A major cause of human blindness is the death of rod photoreceptors. As rods degenerate, synaptic structures between rod and rod bipolar cells dissolve and the rod bipolar cells extend their dendrites and occasionally make aberrant contacts. Such changes are broadly observed in blinding disorders caused by photoreceptor cell death and is thought to occur in response to deafferentation. How the remodeled retinal circuit affect visual processing following rod rescue is not known. To address this question, we generated transgenic mice wherein a disrupted cGMP-gated channel (CNG) gene can be repaired at the endogenous locus and at different stages of degeneration by tamoxifen-inducible cre-mediated recombination. In normal rods, light-induced closure of CNG channels leads to hyperpolarization of the cell, reducing neurotransmitter release at the synapse. Similarly, rods lacking CNG channel exhibit a resting membrane potential that was ~10mV hyperpolarized compared to WT rods, indicating diminished glutamate release. Retinas from these mice undergo stereotypic retinal remodeling as a consequence of rod malfunction and degeneration. Upon tamoxifen-induced expression of CNG channels, rods recovered their structure and exhibited normal light responses. Moreover, we show that the adult mouse retina displays a surprising degree of plasticity upon activation of rod input. Wayward bipolar cell dendrites establish contact with rods to support normal synaptic transmission, which is propagated to the retinal ganglion cells. These findings demonstrate remarkable plasticity extending beyond the developmental period and support efforts to repair or replace defective rods in patients blinded by rod degeneration.

Significance Statement

Current strategies for treatment of neurodegenerative disorders are focused on the repair of the primary affected cell type. However, the defective neuron functions within a complex neural circuitry, which also becomes degraded during disease. It is not known whether a rescued neuron and the remodeled circuit will establish communication to regain normal function. We show that the adult mammalian neural retina exhibits a surprising degree of plasticity following rescue of rod photoreceptors. The wayward rod bipolar cell dendrites re-establish contact with rods to support normal synaptic transmission, which is propagated to the retinal ganglion cells. These findings support efforts to repair or replace defective rods in patients blinded by rod cell loss.
Autonomous planetary rover navigation via active SLAM
Authors: Li Guoqing , Geng Yunhai , Zhang Wenzheng
Published: November 2018

Purpose

This paper aims to introduce an efficient active-simultaneous localization and mapping (SLAM) approach for rover navigation, future planetary rover exploration mission requires the rover to automatically localize itself with high accuracy.

Design/methodology/approach

A three-dimensional (3D) feature detection method is first proposed to extract salient features from the observed point cloud, after that, the salient features are employed as the candidate destinations for re-visiting under SLAM structure, followed by a path planning algorithm integrated with SLAM, wherein the path length and map utility are leveraged to reduce the growth rate of state estimation uncertainty.

Findings

The proposed approach is able to extract distinguishable 3D landmarks for feature re-visiting, and can be naturally integrated with any SLAM algorithms in an efficient manner to improve the navigation accuracy.

Originality/value

This paper proposes a novel active-SLAM structure for planetary rover exploration mission, the salient feature extraction method and active revisit patch planning method are validated to improve the accuracy of pose estimation.
Supportive leadership, proactive personality and employee voice behavior
Authors: Elsaied Mervat Mohamed
Published: November 2018

Purpose

The purpose of this paper is to investigate the mediating role of psychological safety in the relationships among supportive leadership, proactive personality and employee voice behavior.

Design/methodology/approach

The data were collected from 268 employees, and 56 were their immediate supervisors, in three Egyptian companies belonging to footwear and headgear sector. Employees and their immediate supervisors provided data on separate questionnaires and different occasions; an identification number was used to match each employee’s questionnaire with the response of his/her immediate supervisor.

Findings

The results indicated that both supportive leadership and proactive personality had a positive and significant effect on voice behavior. In addition, the results showed that psychological safety fully mediated the relationships among supportive leadership, proactive personality and employee voice behavior.

Originality/value

This study contributes to the literature by linking supportive leadership, proactive personality and employee voice behavior. It clarifies how and why supportive leadership and proactive personality can stimulate voice behavior.
Let home nursing assistant robots see your heart rate
Authors: Wu Han , Wang Tao , Dai Tuo , Wang Xiaoyu , Lin Yuanzhen , Wang Yizhou
Published: November 2018

Purpose

This paper aims to design a vision-based non-contact real-time accurate heart rate (HR) measurement framework for home nursing assistant.

Design/methodology/approach

The study applied Second-Order Blind Signal Identification (SOBI) algorithm to extract remote HR signal and analyzed it with Fast Fourier Transform (FFT). Multiple regions of interest are chosen and analyzed to obtain a more accurate result.

Findings

An accurate non-contact hear rate (HR) measurement framework is proposed and proved to be efficient.

Originality/value

The contributions of this HR measurement framework are as follows: accurate measurement of HR, real-time performance, robust under various scenes such as conversation, lightweight computation which is suitable and necessary for home nursing assistance. This framework is designed to be flexibly used in various real-life scenes such as domestic health assistance and affectively intelligent agents and is proved to be robust under such scenes.
Mobile devices compatibility testing strategy via crowdsourcing
Authors: Naith Qamar , Ciravegna Fabio
Published: November 2018

Purpose

This paper aims to support small mobile application development teams or companies performing testing on a large variety of operating systems versions and mobile devices to ensure their seamless working.

Design/methodology/approach

This paper proposes a “hybrid crowdsourcing” method that leverages the power of public crowd testers. This leads to generating a novel crowdtesting workflow Developer/Tester- Crowdtesting (DT-CT) that focuses on developers and crowd testers as key elements in the testing process without the need for intermediate as managers or leaders. This workflow has been used in a novel crowdtesting platform (AskCrowd2Test). This platform enables testing the compatibility of mobile devices and applications at two different levels, high-level (device characteristics) or low-level (code). Additionally, a “crowd-powered knowledge base” has been developed that stores testing results, relevant issues and their solutions.

Findings

The comparison of the presented DT-CT workflow with the common and most recent crowdtesting workflows showed that DT-CT may positively impact the testing process by reducing time-consuming and budget spend because of the direct interaction of developers and crowd testers.

Originality/value

To authors’ knowledge, this paper is the first to propose crowdtesting workflow based on developers and public crowd testers without crowd managers or leaders, which light the beacon for the future research in this field. Additionally, this work is the first that authorizes crowd testers with a limited level of experience to participate in the testing process, which helps in studying the behaviors and interaction of end-users with apps and obtains more concrete results.
Franchising and initial public offering: a signaling perspective
Authors: Alon Ilan , Elango B.
Published: November 2018

Purpose

The purpose of this paper is to examine the factors associated with franchisors going public using signaling theory. Listing on the stock market is a sign that the business concept has reached a threshold level of acceptance and success. To increase the relevance of this study to practitioners, the authors focus on franchising-specific controllable variables.

Design/methodology/approach

This study uses a sample of 2,134 franchisors from US drawn from a survey by Entrepreneur magazine during the years 2015–2016. Binominal logistic regression models are used for analysis of the data.

Findings

Findings indicate that time to franchise, international operations, franchise association affiliation, disclosure and extent of top management commitment are factors positively related to the likelihood of a franchisor being publicly listed.

Research limitations/implications

Study findings are based on a sample of franchisors from North America, where financial markets are well developed, and due caution should be exercised before generalizations are made to other contexts. A major implication of this study is that signaling theory may provide an important supplement to the already well-entrenched resource-scarcity and agency theoretic explanations in franchising research.

Originality/value

While signaling theory is growing in importance in the franchising literature, this study is the first to uncover the relationship between company signals and initial public offering.
Determinants, transactional alignment, and performance outcomes of franchise contract length
Authors: Gorovaia Nina
Published: November 2018

Purpose

The purpose of this paper is to explore the determinants, transactional alignment and performance outcomes of franchise contract length using transaction costs theory (TCT) and resource-based theory (RBT).

Design/methodology/approach

The author hypothesizes that franchisors choose contract length according to TCT and RBT arguments. TCT explains the safeguarding function of contracts: the franchisors will offer longer contracts when franchisees’ specific investments are high and environmental uncertainty is low. RBT highlights the knowledge leverage function of contracts: the franchisors will offer longer contracts when the brand name and intangible knowledge assets are high. Franchise companies that design contract length aligned with transactional attributes will perform better. The author tests the misalignment hypothesis and comparative performance of franchise contracts by estimating two-stage least squares regression and Heckman two-stage procedure that control for endogeneity and self-selection.

Findings

Empirical data from the German franchise sector support the hypotheses. In addition to the safeguarding function, franchise contracts have an important knowledge leverage function. Longer contracts perform better due to the development of relational strategic assets and stronger commitment.

Research limitations/implications

Franchisors must offer longer contracts when specific investments of franchisees, brand name, intangible knowledge assets are high, and environmental uncertainty is low. Franchisors should invest in the development of relational strategic assets and offer longer contracts for the benefit of superior performance.

Originality/value

The study addresses the significant question of transactional alignment and comparative performance of franchise contracts. It empirically confirms the importance of RBT in explaining contractual choices and performance.
A demographic and psychometric assessment of the Connor-Davidson resilience scale 10 (CD-RISC 10) with a US public accounting sample
Authors: Smith Kenneth J. , Emerson David J. , Schuldt Michael A.
Published: November 2018

Purpose

This paper aims to evaluate the efficacy of the Connor–Davidson Resilience Scale 10 (CD-RISC 10) (Campbell-Sills and Stein, 2007) for use in public accounting settings.

Design/methodology/approach

The analyses include an examination of possible demographic differences in overall score, the scale’s factor structure, the invariance of its factor structure across gender and age groups, the scale’s reliability and its convergent and divergent validity.

Findings

There are significant gender and age group difference in scores, but a common univariate factor structure for the scale. The authors further find that a two-factor solution provides a superior fit to the data compared to the single factor structure used in the most prior research. Spearman–Brown reliability coefficients, item-total correlations and coefficient alphas each support the reliability of the items loading on the scale for the full sample, as well as for each of the above-referenced demographic subsamples.

Research limitations/implications

Limitations are acknowledged related to the use of self-report measures, absence of test-retest score comparisons and convergent and divergent assessments limited to the heterotrait–homomethod approach.

Practical implications

The CD-RISC 10 is an expedient resilience measure, as it can be completed and scored in just a few minutes. Human resource administrators at public accounting firms can use it as an initial screening measure to identify staff who might benefit from resilience training. The paper adds to the appreciation of what not to do in the face of crisis by the government and those in charge of large accounting organizations.

Social implications

The CD-RISC 10 can be used in research and clinical efforts to reduce voluntary turnover of audit staff and enhance the well-being of auditors in the workplace.

Originality/value

This study provides empirical evidence that the CD-RISC 10 is a valid and reliable measure for future assessments of auditor resilience levels.
Salient environmental attributes and their value for small independent grocers
Authors: Srichookiat Sanit , Jindabot Teerasak
Published: November 2018

Purpose

This paper aims to focus on the consumers’ decision process to clarify the salient attributes within the in-store environment of small independent grocers. Thus, the relative importance among environmental factors and their explicit monetary values is clarified.

Design/methodology/approach

The conjoint approach was applied to form a set of hypothetical environments virtualised through an interactive computer-aided simulation. Each of the 241 respondents was asked to evaluate their patronage intention on the basis of a given set of 18 virtual environments.

Findings

The results revealed the greater importance of the social environment in comparison to design and ambient cues, which consumers use in determining their patronage of stores. The final recommended environment offers some explicit value added to customers.

Originality/value

In contrast to most environmental studies, this study considered consumers’ decision processes, using conjoint analysis to clarify the relative importance and value of the environmental aspects affecting small independent grocers.
How mental simulation evokes negative affective misforecasting of hedonic experiences
Authors: Nardini Gia , Lutz Richard J.
Published: November 2018

Purpose

The purpose of this paper is to investigate the relationship between mental simulation and affective misforecasting of hedonic consumption experiences.

Design/methodology/approach

The authors present a series of lab and field studies that manipulate mental simulation and experience type (ordinary versus extraordinary) and measure affective misforecasting and mindfulness. Data were analyzed using a combination of ANOVA and PROCESS.

Findings

Mental simulation before an experience causes negative affective misforecasting to occur for extraordinary experiences but not ordinary experiences. The authors further show that mindfulness mediates the effect of mental simulation on affective misforecasting.

Practical implications

The findings provide insight into how thinking about experiences before consumption affects consumers’ actual engagement with the experience. This paper suggests that, by encouraging consumers to mentally simulate their experiences before consumption, marketers may cause consumers to miss out on enjoying their experiences to the fullest. Instead, marketers may want to maintain some mystique by encouraging consumers to “come see for themselves”.

Originality/value

The authors demonstrate a novel cause of affective misforecasting: mental simulation before the experience and provide initial evidence in support of a novel psychological process explanation (i.e. mindfulness) for the effect of mental simulation on affective misforecasting.
Fatigue life prediction of upper arm suspension using strain life approach
Authors: Kahoul Hafida , Belhour Samira , Bellaouar Ahmed , Dron Jean Paul
Published: November 2018

Purpose

This paper aims to present the fatigue life behaviour of upper arm suspension. The main objectives are to predict the fatigue life of the component and to identify the critical location. In this analysis, three aluminium alloys were used for the suspension, and their fatigue life was compared to select the suitable material for the suspension arm.

Design/methodology/approach

CAD model was prepared using Solid Works software, and finite element analysis was done using ANSYS 14.0 software by importing the Parasolid file to ANSYS. The model is subjected to loading and boundary conditions; the authors consider a vertical force with constant amplitude applied at the bushing that connected to the tire, the others two bushing that connected to the body of the car are constraint. Tetrahedral elements given enhanced results as compared to other types of elements; therefore, the elements (TET 10) are used. The maximum principal stress was considered in the linear static analysis, and fatigue analysis was done using strain life approach.

Findings

Life and damage are evaluated and the critical location was considered at node 63,754. From the fatigue analysis, aluminium alloys 7175-T73 (Al 90%-Zn 5.6%-Mg 2.5% -… …) and 2014-T6 (Al 93.5%-Cu 4.4%-Mg 0.5%… …) present a similar behaviour as compared to 6061-T6 (Al 97.9%-Mg 1.0%-Si 0.6%… … .); in this case of study, these lather are considered to be the materials of choice to manufacture the suspension arms; but 7175-T73 aluminium alloys remain the material with a better resistance to fatigue.

Originality/value

By the finite element analysis method and assistance of ANSYS software, it is able to analyse the different car components from varied aspects such as fatigue, and consequently save time and cost. For further research, the experimental works under controlled laboratory conditions should be done to determine the validation of the result from the software analysis.
Stability analysis of mobile cranes and determination of outriggers loading
Authors: Romanello Giuseppe
Published: November 2018

Purpose

The purpose of this paper is to develop mathematical tools that are reliable and easily implementable in computer codes, which address the determination of the outriggers reaction of mobile cranes and the monitoring of the actual stability margin available during lift operations.

Design/methodology/approach

An algorithm that determines the load transmitted to the ground by a mobile crane with four outriggers has been developed. Static theory of rigid body is adopted for the development of the algorithm and the static indeterminancy, due to the presence of more than three outriggers, is eluded through the adoption of specific hypotheses. An analysis of crane stability is also performed, and a method to monitor the actual stability behavior during lift operations is suggested.

Findings

A case study is proposed to test the algorithm and outcomes show a good matching with the actual outriggers reaction measured during a test conduct in situ. Two indices are introduced as a measure of the stability margin.

Research limitations/implications

The method developed accounts only for gravitational forces statically applied. Future works should be addressed to extend the model to the effect of wind and inertial forces.

Practical implications

This paper supplies a reliable tool to assess, in the design phase of a lifting operation, the compliance between bearing capacity of the ground and loads transmitted by outriggers. The method proposed for the analysis of the stability behavior is suitable for the development of an anti-upset device.

Originality/value

This study contributes to efforts to increase safety during lifting operations with mobile cranes. The method proposed is applicable to cranes with any geometry of the outriggers pattern and is extensible to a number of outriggers greater than four. Furthermore, the evaluation of the measure in real time of the stability margin, is not affected by the data entered by the crane’s operator with the consequence that human factor does not affect this measure.
Using embodied experiences to re-design enabling technologies
Authors: Joshi Suhas Govind
Published: November 2018

Purpose

This study introduces a phenomenological approach to the design of enabling technologies for older adults focusing on capabilities rather than disabilities. The purpose of this paper is to use embodied experiences to structure an alternative understanding of the human–technology relationship and demonstrates the significance and implications of this approach.

Design/methodology/approach

In total, 31 older citizens (M=80.5 years, SD=5.97 years) were engaged in a participatory design process revolving around the embodied experiences of the participants. The aim was to design new wireless chargers for their existing enabling technologies. The paper presents design results and statistical analyses of performance evaluations.

Findings

The co-designed alternatives were compared to the current alternative. The statistical analyses revealed an average increase in performance of 45.35 percent across all participants when using designs anchored in embodied experiences. The significance of these results suggests that a shift from disabilities to capabilities provides new opportunities to understand and facilitate interaction between older adults and technology.

Research limitations/implications

The study follows the theoretical argument into real-use scenarios involving co-designed artifacts to demonstrate how the suggested approach can be a viable alternative strategy to how we facilitate the design of enabling technologies for older adults.

Originality/value

The suggested design approach contributes to the ongoing development of enabling technologies for older adults by introducing a respectful and inclusive alternative strategy.
Freedom, competition and bank profitability in Sub-Saharan Africa
Authors: Sarpong-Kumankoma Emmanuel , Abor Joshua , Aboagye Anthony Quame Q. , Amidu Mohammed
Published: November 2018

Purpose

This paper aims to examine the effects of financial freedom and competition on bank profitability.

Design/methodology/approach

The study uses system generalized method of moments and data from 139 banks across 11 Sub-Saharan African countries during the period 2006-2012.

Findings

The results of the study show that higher market power (less competition) is positively related to bank profitability, but operating efficiency is a more important determinant of profitability than market power. Also, both financial freedom and economic freedom show a positive impact on bank profits. The authors find evidence that banks with higher market power operating in countries with higher freedom for banking activities are more profitable than their counterparts in countries with greater restrictions on banking activities.

Practical implications

The results have shown that allowing banks greater freedom to operate would enhance their performance, without necessarily damaging the economy, as operating efficiency appears to be a more important reason for the observed profitability than market power.

Originality/value

This study provides insight on the ambiguous relationship between competition and bank profitability by considering the moderating effect of financial freedom which has not been taken into account in previous studies.