bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgical management of tailgut cysts
Authors: Li Jiannan , Song Xiaowei , Shi Jian , Zhang Kai , Liu Tongjun
Published: February 2019

Rationale:

Tailgut cysts are a type of very rare congenital polycystic lesions that are always located posterior to the rectum and anterior to the sacrum. The symptoms of tailgut cysts are nonspecific and misleading. Therefore, a full understanding of the characteristics of tailgut cysts is important for their diagnosis and treatment.

Patient concerns:

We report a 46-year-old female with a sacrococcygeal mass that had been present for about 2 years.

Diagnoses:

Pelvic magnetic resonance imaging (MRI) indicated several cystic masses, the largest of which had a diameter of about 2.8 cm, near the ligaments of the sacrospinous and rectum. Pathological examination confirmed the tailgut cysts, with no signs of malignant transformation.

Interventions:

The patient received complete surgical cysts resection, which was performed through the sacrococcygeal region.

Outcomes:

The patient recovered well with no obvious complication and was discharged on the sixth-day post-surgery. Follow-up 6 months later revealed no signs of cyst recurrence.

Lessons:

The symptoms and diagnostic characteristics of tailgut cysts should be fully understood. Complete surgical resection through the sacrococcygeal region is vital to treat tailgut cysts.
Renal impairment is associated with increased risk of mortality in patients with cirrhosis
Authors: Umemura Takeji , Joshita Satoru , Shibata Soichiro , Sugiura Ayumi , Yamazaki Tomoo , Fujimori Naoyuki , Matsumoto Akihiro , Tanaka Eiji
Published: February 2019

Although renal impairment is a frequent complication in cirrhosis that is associated with a poor prognosis, little has been reported on the clinical significance of renal impairment in cirrhosis in Japan. This retrospective study assessed the impact of renal impairment on mortality in Japanese cirrhosis patients taking conventional diuretics.

A total of 157 patients with cirrhosis receiving diuretic treatment were evaluated for the presence and status of renal impairment, defined as an increase in serum creatinine of ≥ 0.3 mg/dL or by ≥ 50%, and then classified according to the International Club of Ascites (ICA)-Acute Kidney Injury (AKI) staging system.

Eighty of 157 (51%) patients fulfilled the criteria for renal impairment. Thirty-four (43%) patients had ICA-AKI stage 1, 32 (40%) stage 2, and 14 (18%) stage 3. Multivariate analysis revealed female gender (hazard ratio [HR] = 0.407, 95% confidence interval = 0.193–0.857; P = .018), ALT ≥35 IU/L (HR = 3.841, 95% confidence interval = 1.785–8.065; P = .001), and the presence of renal impairment (HR = 4.275, 95% confidence interval = 1.962–9.312; P < .001) as independent factors significantly increasing the risk of mortality. Cumulative survival rates increased significantly with ICA–AKI stage (log-rank test, P = .009).

Renal impairment was a predictive marker of mortality in Japanese patients with cirrhosis. Stratification according to ICA–AKI criteria of kidney function impairment may be a good prognostic indicator of cirrhosis outcome.
Surgical outcomes and quality of life between laparoscopic and open approach for hepatic hemangioma
Authors: Liu Qinqin , Liu Fei , Ding Jingjing , Wei Yonggang , Li Bo
Published: February 2019

The main objective of the study was to compare the surgical outcomes and quality of life (QOL) of patients with hepatic hemangioma either by laparoscopic or open surgery using a propensity score analysis.

We retrospectively reviewed patients with hepatic hemangioma undergoing laparoscopic liver surgery (LLS) or open liver surgery (OLS) between January 2016 and December 2017. Intraoperative and postoperative characteristics, and quality of life, according to Short Form-36 Healthy Survey (SF-36) questionnaire, were compared between groups. We performed 1:1 propensity score matching (PSM) between the LLS and OLS groups.

A total of 205 patients who involved in the analysis (80 LLS vs 125 OLS) were matched (1:1) by age, gender, body mass index (BMI), American Society of Anesthesiologists (ASA) score, previous upper abdominal surgery, comorbidities, operation method, type of resection, tumor localization, size, and number. After PSM, 73 well-matched patients in each group were obtained. LLS was associated with significantly less blood loss, shorter postoperative hospital stay and fewer complications. The QOL scores weren’t significantly different between the 2 groups, though the LLS group tended to be superior to the OLS group in terms of bodily pain (BP) and mental health (MH) at 3 months after surgery.

In comparison with the conventional open approach, laparoscopic liver surgery for hepatic hemangioma appears to have improved short-term surgical outcomes and comparable QOL in selected patients.
A Tool to Guide Clinical Nurse Specialist Orientation, Professional Development, and Evaluation
Authors: McNeill Margaret M. , Ahluwalia Anushree R. , Young Samantha , Randell Tania Vucich , Moore Denise Ann
Published: February 2019

Purpose/Objectives:

Currently, orientation for clinical nurse specialists (CNSs) in the Baltimore region is based on past practices: facility-specific or position-specific. A Chesapeake Bay affiliate work group identified a need to develop a theory-driven, competency-based program and tool to guide orientation and ongoing professional development reflecting the scope of CNS practice.

Description of the Project/Program:

The tool incorporates Benner’s concepts of novice-to-expert competence levels, guides progressive development of the CNS, and has relevant assessment metrics that highlight contributions to the patient, nurse, and system.

Outcome:

The group developed a comprehensive orientation tool grounded in the spheres of influence and advanced practice competencies and specific, measurable behavioral statements related to competencies from the 2018 National Association of Clinical Nurse Specialists’ draft. This program is adaptable to guide the practice of a CNS in any facility, validate competence, and relate to those with varied experience in the role.

Conclusion:

In a method similar to the process for developing nationally recognized educational standards used to develop the competencies, the program was revised based on an iterative, stepwise process. It was distributed to the membership for evaluation and feedback, which was incorporated into the final version.
A Multifaceted Approach to the Prevention of Clostridioides (Clostridium) Difficile
Authors: Pate Kimberly , Reece Jennifer , Smyre Alex
Published: February 2019

Purpose/Objectives

The purpose of this project was to design and implement a sustainable program to reduce hospital-acquired cases of Clostridioides difficile.

Description of the Project

Experiencing higher rates in a large, academic medical center, hospital leaders were assembled. The overall facility rate was 6.9% in 2014 with a first quarter rate of 8.4% in 2015. Individual unit rates were as high as 19.8%. A team of key stakeholders was assembled to plan, execute, and reevaluate targeted solutions. Strategies implemented were an innovative, automated screening tool, an evidence-based prevention bundle; and staff education.

Outcomes

A facility-wide C difficile prevention program was implemented with a sustained decrease in rates observed from 8.4% in the first quarter of 2015 to 6.0% in the fourth quarter of 2017. The standardized infection ratio ranged from 0.541 to 0.889, consistently below the national mean.

Conclusion

Clostridioides difficile is a leading cause of hospital-associated diarrhea and a tremendous burden on healthcare systems increasing morbidity, mortality, and financial strain. A multidisciplinary, multifaceted approach was critical to ensure early detection, reduce risk of transmission, and decrease overall rates.
Health-Related Quality of Life Among Survivors of Pediatric Sepsis*
Authors: Killien Elizabeth Y. , Farris Reid W. D. , Watson R. Scott , Dervan Leslie A. , Zimmerman Jerry J.
Published: February 2019

Objectives:

Mortality from pediatric sepsis has steadily declined over the past several decades; however, little is known about morbidity among survivors. We aimed to determine the prevalence of and risk factors for failure to recover to baseline health-related quality of life following community-acquired pediatric sepsis.

Design:

Retrospective cohort study.

Setting:

Seattle Children’s Hospital.

Patients:

Children aged 1 month to 21 years admitted to the inpatient wards or ICUs from 2012 to 2015 who met 2005 consensus sepsis criteria within 4 hours of hospitalization and were enrolled in the hospital’s Outcomes Assessment Program with baseline, admission, and post-discharge health-related quality of life data available.

Interventions:

None.

Measurements and Main Results:

We assessed health-related quality of life with the Pediatric Quality of Life Inventory for pre-admission baseline, admission, and post-discharge (median, 31 d) status. We determined associations between patient and illness characteristics with failure to recover within 4.5 points of baseline at follow-up (the minimum clinically significant difference between two scores). Of 790 patients, 23.8% failed to recover to baseline health-related quality of life at follow-up. Factors associated with failure to recover were septic shock, older age, private insurance, complex chronic disease, immune compromise, CNS infection or bacteremia, ICU admission, and longer length of stay. On multivariable analysis controlling for time to follow-up, failure to recover was independently associated with septic shock (relative risk, 1.79; 95% CI, 1.24–2.58), older age (relative risk, 1.02/yr; 95% CI, 1.01–1.05), immune compromise (relative risk, 1.83; 95% CI, 1.40–2.40), and length of stay (relative risk, 1.03/d; 95% CI, 1.01–1.04).

Conclusions:

Nearly one-quarter of children surviving hospitalization for community-acquired sepsis experienced a clinically significant deterioration in health-related quality of life. We identify risk factors for poor outcomes following sepsis and highlight the need for ongoing evaluation and treatment by primary and specialty care providers for pediatric sepsis survivors after hospital discharge.
Proving the Effectiveness of the Fundamentals of Robotic Surgery (FRS) Skills Curriculum
Authors: Satava Richard M. , Stefanidis Dimitrios , Levy Jeffrey S. , Smith Roger , Martin John R. , Monfared Sara , Timsina Lava R. , Darzi Ara Wardkes , Moglia Andrea , Brand Timothy C. , Dorin Ryan P. , Dumon Kristoffel R. , Francone Todd D. , Georgiou Evangelos , Goh Alvin C. , Marcet Jorge E. , Martino Martin A. , Sudan Ranjan , Vale Justin , Gallagher Anthony G.
Published: February 2019

Objective:

To demonstrate the noninferiority of the fundamentals of robotic surgery (FRS) skills curriculum over current training paradigms and identify an ideal training platform.

Summary Background Data:

There is currently no validated, uniformly accepted curriculum for training in robotic surgery skills.

Methods:

Single-blinded parallel-group randomized trial at 12 international American College of Surgeons (ACS) Accredited Education Institutes (AEI). Thirty-three robotic surgery experts and 123 inexperienced surgical trainees were enrolled between April 2015 and November 2016. Benchmarks (proficiency levels) on the 7 FRS Dome tasks were established based on expert performance. Participants were then randomly assigned to 4 training groups: Dome (n = 29), dV-Trainer (n = 30), and DVSS (n = 32) that trained to benchmarks and control (n = 32) that trained using locally available robotic skills curricula. The primary outcome was participant performance after training based on task errors and duration on 5 basic robotic tasks (knot tying, continuous suturing, cutting, dissection, and vessel coagulation) using an avian tissue model (transfer-test). Secondary outcomes included cognitive test scores, GEARS ratings, and robot familiarity checklist scores.

Results:

All groups demonstrated significant performance improvement after skills training (P < 0.01). Participating residents and fellows performed tasks faster (DOME and DVSS groups) and with fewer errors than controls (DOME group; P < 0.01). Inter-rater reliability was high for the checklist scores (0.82–0.97) but moderate for GEARS ratings (0.40–0.67).

Conclusions:

We provide evidence of effectiveness for the FRS curriculum by demonstrating better performance of those trained following FRS compared with controls on a transfer test. We therefore argue for its implementation across training programs before surgeons apply these skills clinically.
Open Versus Laparoscopic Versus Robotic Versus Transanal Mesorectal Excision for Rectal Cancer
Authors: Simillis Constantinos , Lal Nikhil , Thoukididou Sarah N. , Kontovounisios Christos , Smith Jason J. , Hompes Roel , Adamina Michel , Tekkis Paris P.
Published: February 2019

Objective:

To compare techniques for rectal cancer resection.

Summary Background Data:

Different surgical approaches exist for mesorectal excision.

Methods:

Systematic literature review and Bayesian network meta-analysis performed.

Results:

Twenty-nine randomized controlled trials included, reporting on 6237 participants, comparing: open versus laparoscopic versus robotic versus transanal mesorectal excision. No significant differences identified between treatments in intraoperative morbidity, conversion rate, grade III/IV morbidity, reoperation, anastomotic leak, nodes retrieved, involved distal margin, 5-year overall survival, and locoregional recurrence. Operative blood loss was less with laparoscopic surgery compared with open, and with robotic surgery compared with open and laparoscopic. Robotic operative time was longer compared with open, laparoscopic, and transanal. Laparoscopic operative time was longer compared with open. Laparoscopic surgery resulted in lower overall postoperative morbidity and fewer wound infections compared with open. Robotic surgery had fewer wound infections compared with open. Time to defecation was longer with open surgery compared with laparoscopic and robotic. Hospital stay was longer after open surgery compared with laparoscopic and robotic, and after laparoscopic surgery compared with robotic. Laparoscopic surgery resulted in more incomplete or nearly complete mesorectal excisions compared with open, and in more involved circumferential resection margins compared with transanal. Robotic surgery resulted in longer distal resection margins compared with open, laparoscopic, and transanal.

Conclusions:

The different techniques result in comparable perioperative morbidity and long-term survival. The laparoscopic and robotic approaches may improve postoperative recovery, and the open and transanal approaches may improve oncological resection. Technique selection should be based on expected benefits by individual patient.
Inter- and Intra-Generation Genomic Predictions for Douglas-fir Growth in Unobserved Environments
Authors: Ratcliffe Blaise , Thistlethwaite Francis , El-Dien Omnia Gamal , Cappa Eduardo P. , Porth Ilga , Klápště Jaroslav , Chen Charles , Wang Tongli , Stoehr Michael , El-Kassaby Yousry A.
Published: February 2019

Conifers are prime candidates for genomic selection (GS) due to their long breeding cycles. Previous studies have shown much reduced prediction accuracies (PA) of breeding values in unobserved environments, which may impede its adoption. The impact of explicit environmental heterogeneity modeling including genotype-by-environment (G×E) interaction effects using environmental covariates (EC) in a reaction-norm genomic prediction model was tested using single-step GBLUP (ssGBLUP). A three-generation coastal Douglas-fir experimental population with 14 genetic trials (n = 13,615) permitted estimation of intra- and inter-generation PA in unobserved environments using 66,969 SNPs derived from exome capture. Intra- and inter-generation PAs ranged from 0.447-0.640 and 0.317-0.538, respectively. The inclusion of ECs in the prediction models explained up to 23% of the phenotypic variation for the fully specified model and resulted in the best model fit. Modeling G×E effects in the training population increased PA up to 6% and 13% over the base model for inter- and intra-generations, respectively. GS-PA can be substantially improved using ECs to explain environmental heterogeneity and G×E effects. The ssGBLUP methodology allows historical genetic trials containing non-genotyped samples to contribute in genomic prediction, and, thus, effectively boosting training population size which is a critical step. Further pheno- and enviro-typing developments may improve GS-PA.
Epidemiological Analysis of Ear Diseases in 221 Dogs in Northwest of China
Authors: Tang F-L. , Yang H-Q. , Ma X-W. , Lu D-Z.
Published: February 2019

Ear disease is a relatively common disease in veterinary, and it will great effect on the pets’ life. This study mainly collected and collated the cases of Xi’an Teaching Hospital of Northwest A&F University from 2012 to 2016, and conducted an epidemiological analysis of the incidence of ear disease in dogs. In this study, the common ear diseases in dogs were divided into otitis externa, otitis media, otitis interna, and ear hematoma. The results showed that the total number of dog ear disease cases was 221, the highest incidence was otitis externa (84.62%), and the main cause of otitis externa was the bacterial infection (44.10%), which followed by fungal infection (32.31%). The ratio of male to female is 1:1.5. In terms of the dog species, the highest incidence was Teddy (18.55%), followed by the Golden Retriever (10.41%). The most common ear diseases in puppies was otitis externa, ear canal hyperplasia and ear canal tumors occur mainly in older dogs. Through the analysis of the 221 cases of ear diseases, we could better understand the development and epidemiology of dog ear diseases, and provide some reference for clinical diagnosis, treatment and prevention of dog ear diseases.
Murine Surf4 is essential for early embryonic development
Authors: Emmer Brian T. , Lascuna Paul J. , Kotnik Emilee N. , Saunders Thomas L. , Khoriaty Rami , Ginsburg David
Published: February 2019

Newly synthesized proteins co-translationally inserted into the endoplasmic reticulum (ER) lumen may be recruited into anterograde transport vesicles by their association with specific cargo receptors. We recently identified a role for the cargo receptor SURF4 in facilitating the secretion of PCSK9 in cultured cells. To examine the function of SURF4 in vivo, we used CRISPR/Cas9-mediated gene editing to generate mice with germline loss-of-function mutations in Surf4. Surf4+/- mice exhibited grossly normal appearance, behavior, body weight, fecundity, and organ development and demonstrated no significant alterations in circulating plasma levels of PCSK9, apolipoprotein B, or total cholesterol. Surf4-/- mice exhibit embryonic lethality, with complete loss of all Surf4-/- offspring between embryonic days 3.5 and 9.5. Taken together with the much milder phenotypes of PCSK9 or apolipoprotein B deficiency in mice, these findings imply the existence of additional SURF4 cargoes or functions that are essential for murine early embryonic development.
Multiscale model of integrin adhesion assembly
Authors: Bidone Tamara C , Skeeters Austin V , Oakes Patrick W , Voth Gregory A
Published: February 2019

The ability of adherent cells to form adhesions is critical to several phases of their physiology. The assembly of adhesions is mediated by several types of integrins. These integrins differ in physical properties, including rate of diffusion on the plasma membrane, rapidity of changing conformation from bent to extended, affinity for extracellular matrix ligands, and lifetimes of their ligand-bound states. However, the way in which nanoscale physical properties of integrins ensure proper adhesion assembly remains elusive. We observe experimentally that both beta-1 and beta-3 integrins localize in nascent adhesions at the cell leading edge. In order to understand how different nanoscale parameters of beta-1 and beta-3 integrins mediate proper adhesion assembly, we therefore develop a coarse-grained computational model. Results from the model demonstrate that morphology and distribution of nascent adhesions depend on ligand binding affinity and strength of pairwise interactions. Organization of nascent adhesions depends on the relative amounts of integrins with different bond kinetics. Moreover, the model shows that the architecture of an actin filament network does not perturb the total amount of integrin clustering and ligand binding; however, only bundled actin architectures favor adhesion stability and ultimately maturation. Together, our results support the view that cells can finely tune the expression of different integrin types to determine both structural and dynamic properties of adhesions.
The exotic species Senecio inaequidens pays the price for arriving late in temperate European grasslands
Authors: Delory Benjamin , Weidlich Emanuela W. A. , Kunz Miriam , Neitzel Joshua , Temperton Vicky
Published: February 2019

The South African ragwort (Senecio inaequidens DC.) is one of the fastest exotic plant invaders in Central Europe but, despite its large distribution area, it is still not commonly found in European grasslands. In order to better understand the mechanisms behind invasion resistance of grassland communities to S. inaequidens, we determined (1) to what extent the timing of arrival of S. inaequidens in the community affected its invasiveness as well as the performance of the native species, and (2) how the direction and strength of priority effects were affected by the composition of the native community being invaded, particularly with regard to the presence of N2-fixing species (legumes).
In a greenhouse experiment, we manipulated the timing of arrival of the exotic species in the community and the composition of the native background community to test the influence of these factors on the productivity and N content of exotic and native species. Using a set of interaction indices, we also investigated if the plant species origin (native or exotic) and the native community composition affected the benefit of arriving early and the cost of arriving late (i.e., priority effects) in the community.
We showed that both exotic and native species created inhibitory priority effects for late-arriving species. The establishment success of S. inaequidens strongly depended on its timing of arrival in a grassland community. On average, S. inaequidens benefited more from arriving early than the natives. We did not find any evidence to support that the presence of legumes in the background community would favour invasion by S. inaequidens. When natives arrived later than S. inaequidens, however, priority effects were weaker when legumes were present in the native community.
Synthesis: we showed that priority effects created by natives can lower the risk of invasion by S. inaequidens and are an important mechanism to explain why this exotic species is not commonly found in European grasslands yet. Our results suggest that an early arrival of this species at a site with low native species abundance (e.g., following a disturbance) is a scenario that could favour invasion by S. inaequidens.
Aurora kinase Ipl1 facilitates bilobed distribution of clustered kinetochores to ensure error-free chromosome segregation in Candida albicans
Authors: Varshney Neha , Sanyal Kaustuv
Published: February 2019

Candida albicans, an ascomycete, has an ability to switch to diverse morphological forms. While C. albicans is predominatly diploid, it can tolerate aneuploidy as a survival strategy under stress. Aurora kinase B homolog Ipl1 is a critical ploidy regulator that controls microtubule dynamics and chromosome segregation in Saccharomyces cerevisiae. In this study, we show that Ipl1 in C. albicans has a longer activation loop than that of the well-studied ascomycete S. cerevisiae. Ipl1 localizes to the kinetochores during the G1/S phase and associates with the spindle during mitosis. Ipl1 regulates cell morphogenesis and is required for cell viability. Ipl1 monitors microtubule dynamics which is mediated by separation of spindle pole bodies. While Ipl1 is dispensable for maintaining structural integrity and clustering of kinetochores in C. albicans, it is required for the maintenance of kinetochore geometry to form bilobed structures along the mitotic spindle, a feature of Ipl1 that was not observed in other yeasts. Depletion of Ipl1 results in erroneous kinetochore-microtubule attachments leading to aneuploidy-associated resistance to fluconazole, the most common anti-fungal drug used to treat Candida infections. Taking together, we suggest that Ipl1 spatiotemporally ensures kinetochore geometry to facilitate bipolar spindle assembly crucial for ploidy maintenance in C. albicans.
Prediction of Four Novel SNPs V17M, R11H, A66T, and F57S in the SBDS Gene Possibly Associated with Formation of Shwachman-Diamond Syndrome, using an Insilico Approach
Authors: Sati Anfal Osama Mohamed , Ali Sara Ali Abdallah , Abduallah Rouaa Babikir Ahmed , Elsied Manal Satti Awad , Salih Mohamed Ahmed
Published: February 2019

Shwachman-Diamond syndrome SDS (MIM 260400) is an autosomal recessive disorder. Characterized by exocrine insufficiency of the pancreas, bone marrow hypoplasia resulting in cytopenias, especially neutropenia, variable degree of skeletal abnormalities, failure to thrive, and increasing risk of developing myelodysplasia or transformation to leukemia. SDS is mainly caused by Shwachman Bodian Diamond Syndrome gene (MIM ID 607444). SBDS gene is 14899 bp in length, located in chromosome seven in the eleventh region of the long arm, and is composed of five exons. It's a ribosomal maturation factor which encodes a highly conservative protein that has widely unknown functions despite of its abundance in the nucleolus. A total number of 53 SNPs of homo sapiens SBDS gene were obtained from the national center for biotechnology information (NCBI) analyzed using translational tools, 7 of which were deleterious according to SIFT server and were further analyzed using several softwares (Polyhen-2, SNPs&Go, I-Mutant 2.0, Mutpred2, structural analysis soft wares and multiple sequence alignment tool). Four SNPs (rs11557408 (V17M), rs11557409 (R11H), rs367842164 (A66T), and rs376960114 (F57S)) were predicted to be disease causing, localized at highly conservative regions of the SBDS protein and were not reported in any previous study. In addition, the study predicts new functions of the SBDS protein DNA related, and suggests explanations for Patients developing cytopenias and failure to thrive through genetic coexpression and physical interaction with RBF1 and EXOSC3, respectively.
Soluble tubulin is locally enriched at mitotic centrosomes in C. elegans
Authors: Baumgart Johannes , Kirchner Marcel , Redemann Stefanie , Woodruff Jeffrey , Verbavatz Jean-Marc , Julicher Frank , Hyman Anthony , Mueller-Reichert Thomas , Brugues Jan
Published: February 2019

During mitosis, the centrosome expands its capacity to nucleate microtubules. Understanding the mechanisms of centrosomal microtubule nucleation is, however, constrained by a lack of knowledge of the amount of soluble and polymer tubulin at mitotic centrosomes. Here we combined light microscopy and serial-section electron tomography to measure the amount of dimer and polymer at mitotic centrosomes in early C. elegans embryos. We show that a C. elegans one-cell stage centrosome at metaphase contains more than ten thousand microtubules with a total polymer concentration of 230 μM. Centrosomes concentrate soluble α/β tubulin by about tenfold over the cytoplasm, reaching peak values of 470 μM, giving a combined total monomer and polymer tubulin concentration at centrosomes of up to 660 μM. These findings support in vitro data suggesting that microtubule nucleation in C. elegans centrosomes is driven in part by concentrating soluble tubulin.
Rotary substates of mitochondrial ATP synthase reveal the basis of flexible F1-Fo coupling
Authors: Murphy Bonnie J. , Klusch Niklas , Langer Julian D. , Mills Deryck J. , Yildiz Özkan , Kühlbrandt Werner
Published: February 2019

F1Fo-ATP synthases play a central role in cellular metabolism, making the energy of the proton-motive force across a membrane available for a large number of energy-consuming processes. We determined the single-particle cryo-EM structure of active dimeric ATP synthase from mitochondria of Polytomella sp. at 2.7- 2.8 Å resolution. Separation of 13 well-defined rotary substates by 3D classification provides a detailed picture of the molecular motions that accompany c-ring rotation and result in ATP synthesis. Crucially, the F1 head rotates along with the central stalk and c-ring rotor for the first ~30° of each 120° primary rotary step. The joint movement facilitates flexible coupling of the stoichiometrically mismatched F1 and Fo subcomplexes. Flexibility is mediated primarily by the interdomain hinge of the conserved OSCP subunit, a well-established target of physiologically important inhibitors. Our maps provide atomic detail of the c-ring/a-subunit interface in the membrane, where protonation and deprotonation of c-ring cGlu111 drives rotary catalysis. An essential histidine residue in the lumenal proton access channel binds a strong non-peptide density assigned to a metal ion that may facilitate c-ring protonation, as its coordination geometry changes with c-ring rotation. We resolve ordered water molecules in the proton access and release channels and at the gating aArg239 that is critical in all rotary ATPases. We identify the previously unknown ASA10 subunit and present complete de novo atomic models of subunits ASA1-10, which make up the two interlinked peripheral stalks that stabilize the Polytomella ATP synthase dimer.
Threonine synthase CoTHR4 is involved in infection-related morphogenesis during the pre-penetration stage in Colletotrichum orbiculare
Authors: Harata Ken , Okuno Tetsuro
Published: February 2019

Upon recognition of host plants, Colletotrichum orbiculare, an anthracnose disease fungus of cucurbitaceous plants, initiates morphological differentiation, including conidial germination and appressorium formation on the cuticle layer. The series of infection processes of C. orbiculare requires enormous nutrient and energy, but the surface of the cucurbitaceous hosts is hardly nutrient-rich. Hence, C. orbiculare must exert tight management of its intracellular nutrients in order to properly induce infection-related morphogenesis. Here, we carried out a large-scale insertional mutagenesis screen using Agrobacterium tumefaciens-mediated transformation to identify novel genes involved in the pathogenicity of C. orbiculare and found that CoTHR4-encoded threonine synthase, a homolog of Saccharomyces cerevisiae THR4, is required for pathogenicity and conidiation in C. orbiculare. Threonine supplementation allowed the cothr4 mutant to produce conidia to a level equivalent to that of the wild-type. The conidia produced from the threonine-treated cothr4 mutant failed to germinate in the absence of threonine, but retained the ability to germinate and to form appressoria in the presence of threonine. However, the conidia produced from the threonine-treated cothr4 mutant remained attenuated in pathogenicity on cucumber cotyledons even in the presence of threonine. Cytorrhysis assays revealed that appressoria of the cothr4 mutant induced by exogenous threonine treatment showed low turgor generation. Taken together, these results showed that threonine synthase CoThr4 plays a pivotal role in infection-related morphogenesis during the pre-penetration stage of C. orbiculare.
Proposal for a photoelectron spectroscopy and microscopy beamline (0.5–11 keV) at the High Energy Photon Source
Authors: Tang Kun , Zheng Lei , Wang Jia-Ou , Zhao Yi-Dong
Published: February 2019

An optical design study of a beamline proposed for the new 6 GeV synchrotron, the High Energy Photon Source (HEPS), to be built in Beijing, China, is described. The beamline is designed to cover an energy range from 0.5 to 11 keV with two experimental stations, one for X-ray photoelectron spectroscopy (PES) experiments and the other for photoelectron emission microscopy (XPEEM) experiments. A 5 m APPLE II-type undulator with a relatively long magnetic period (55 mm) is used as the only radiation source. To optimize the optical efficiency for the full energy range, the beamline is split into a soft X-ray branch that is based on a variable-line-spacing plane-grating monochromator and a tender X-ray branch that uses a four-bounce monochromator with three Si channel-cut pairs. To allow both PES and XPEEM to be performed over the entire energy range, two toroidal mirrors and a bendable KB mirror pair are employed to deliver the soft and tender beams, respectively, to either of two experimental stations.
Integration of facility management and building information modeling (BIM)
Authors: Dixit Manish K. , Venkatraj Varusha , Ostadalimakhmalbaf Mohammadreza , Pariafsai Fatemeh , Lavy Sarel
Published: February 2019

Purpose

The purpose of this study is to investigate factors that impede the integration of facilities management (FM) into building information modeling (BIM) technology. The use of BIM technology in the commercial construction industry has grown enormously in recent years. Its application to FM, however, is still limited. The literature highlights issues that hinder BIM–FM integration, which are studied and discussed in detail in this paper.

Design/methodology/approach

A review of literature is conducted to identify and categorize key issues hampering the application of BIM to FM. This paper has also designed a questionnaire based on a literature review and surveyed FM professionals at two industry events. Using the collected responses, these issues are analyzed and discussed using non-parametric statistical analyses.

Findings

A total of 16 issues are identified through the literature review of 54 studies under the four categories of BIM-execution and information-management, technological, cost-based and legal and contractual issues. The results of the survey of FM professionals (with 57 complete responses) reveal that the single most important issue is the lack of FM involvement in project phases when BIM is evolving.

Originality/value

The findings of this study could assist the construction industry (e.g. building-material and equipment manufacturers, design professionals, general contractors, construction managers, owners and facility managers) with creating guidelines that would help in BIM–FM integration. BIM is a virtual database that contains important design and construction information, which can be used for effective and efficient life cycle management if building data are captured completely and accurately with a facility manager’s involvement.
Estimating student ability and problem difficulty using item response theory (IRT) and TrueSkill
Authors: Lee Youngjin
Published: February 2019

Purpose

The purpose of this paper is to investigate an efficient means of estimating the ability of students solving problems in the computer-based learning environment.

Design/methodology/approach

Item response theory (IRT) and TrueSkill were applied to simulated and real problem solving data to estimate the ability of students solving homework problems in the massive open online course (MOOC). Based on the estimated ability, data mining models predicting whether students can correctly solve homework and quiz problems in the MOOC were developed. The predictive power of IRT- and TrueSkill-based data mining models was compared in terms of Area Under the receiver operating characteristic Curve.

Findings

The correlation between students’ ability estimated from IRT and TrueSkill was strong. In addition, IRT- and TrueSkill-based data mining models showed a comparable predictive power when the data included a large number of students. While IRT failed to estimate students’ ability and could not predict their problem solving performance when the data included a small number of students, TrueSkill did not experience such problems.

Originality/value

Estimating students’ ability is critical to determine the most appropriate time for providing instructional scaffolding in the computer-based learning environment. The findings of this study suggest that TrueSkill can be an efficient means for estimating the ability of students solving problems in the computer-based learning environment regardless of the number of students.
Ownership, tax and intercorporate loans in China
Authors: Huang Wei
Published: February 2019

Purpose

This paper aims to investigate the interconnections between corporate ownership, tax system and controlling shareholder tunneling through intercorporate loans in an emerging market setting.

Design/methodology/approach

China’s Enterprises Income Tax reform in 2008 abolished its previous multiple-tiers tax system under which foreign direct investment (FDI) firms enjoyed preferential tax rates than domestic firms by introducing a new unified-rate tax system. Using difference-in-differences tests, the author analyzes changes of controlling shareholders tunneling through intercorporate loans among Chinese listed companies around this reform.

Findings

The author documents significant reductions of intercorporate loans after the reform. More importantly, the author reveals that foreign-invested firms experienced larger reductions of intercorporate loans than domestic firms. The author also shows that state association matters for domestic firms’ response to the reform. In addition, the author documents positive stock market reaction to the tax reform announcement for firms that exhibited higher level of tunneling prior to the reform, indicating market expectation of reduced principal-principal conflict post-reform.

Research limitations/implications

The findings suggest effective corporate governance system is warranted to constrain intercorporate fund transfers in emerging markets where tax incentives are used for attracting inward foreign direct investments. Institutional reforms in emerging markets aimed at removing market frictions can alleviate the problem of controlling shareholder expropriations of minority interests or tunneling.

Originality/value

This is a pioneering study that reveals the role of tax as a public governance mechanism in weak minority investor protection environment.
Context, gender and entrepreneurial intentions
Authors: van Ewijk Anne Rienke , Belghiti-Mahut Sophia
Published: February 2019

Purpose

This paper aims to explore how gender differences in entrepreneurial intentions (EI) change when entrepreneurship education (EE) is added to the force field of macro-social stimulants and inhibitors of female EI in the particular context of the United Arab Emirates (UAE).

Design/methodology/approach

The study is based on a pre-post survey with entrepreneurship students and students with a similar profile enrolled in other courses (N = 246) at three universities. The three main hypotheses are evaluated through independent-samplest-tests and a hierarchical multiple regression analysis.

Findings

The findings indicate a negative effect of gender stereotypes on female students’ EI in the UAE, regardless of the course type. Furthermore, entrepreneurship courses appear to be more successful than other courses in raising the EI of students in general and female students in particular. Finally, adding EE to the equation of macro-social inhibitors and stimulants of female EI in the UAE seems to tip the balance in favor of the influence of economic affluence, rapid modernization and proactive governmental policies to stimulate the entrepreneurial spirit among female residents. That is, at the end of the entrepreneurship courses, there was no significant gender difference in EI anymore and female students are significantly more likely to experience a positive change in EI than male students.

Research limitations/implications

The literature review identifies the need for future studies to evaluate the impact of variability in sampling and methods among previous studies on gender effects in EE. Building on the findings, future studies could identify which aspects of EE are pivotal for customizing female students’ specific local interests and needs. The study is limited in the sense that the data set did not enable tests of moderators at the course level (which mostly requires more qualitative data) and individual level. In addition, the sample is not representative for all female residents in the UAE at large.

Practical implications

This study might stimulate (UAE) policymakers to increase the scope and quality of EE. In turn, university administrators are recommended to find ways to compensate the self-selection effect (overcome likely opt-out by female students) when entrepreneurship courses are elective.

Originality/value

This exploration was inspired by the strong emphasis that Julie Weeks put on the gendered impact of macro-level factors in business enabling environments (Weeks, 2011). The empirical analysis builds on a conceptual framework that integrates Krueger’s model of EI, theory on gender stereotypes in entrepreneurship and previous literature on the role of EE (reinforcing or mitigating stereotypes). The study is executed in the relatively unexplored context of the UAE, which offers strong macro-social inhibitors for ánd stimulants of female entrepreneurship.
Agenda-setting on traditional vs social media
Authors: Chen Liang , Shi Jingyuan , Guo Yu , Wang Pianpian , Li Yiwei
Published: February 2019

Purpose

The purpose of this paper is to explore and compare haze-related content between traditional and social media in China by applying agenda-setting theory and the extended parallel process model (EPPM). Specifically, this paper examines the correlation between the two forms of media in terms of the ranking of the attributes of haze (i.e. the EPPM components) and the interrelationships among the attributes.

Design/methodology/approach

Content analysis and semantic network analysis were employed to address the research aims.

Findings

The results revealed that more than half of the total messages on both types of media reflected the EPPM components, either threat or efficacy information. However, the imbalance between the threat and efficacy information was more prominent in the haze-related content presented in thePeople’s Dailythan it was on Weibo. In addition, the results from a Spearman’s rank-order correlation and a quadratic assignment procedure (QAP) indicated that there was no significant correlation between thePeople’s Dailyand Weibo in terms of the rankings of the attributes of haze (i.e. the EPPM components) or the interrelationships among the attributes.

Originality/value

This study is the first to apply a theoretical approach to examine and compare the nature of haze-related messages on traditional and social media.
Consumer psychological motivations to customer brand engagement: a case of brand community
Authors: Kumar Jitender , Nayak Jogendra Kumar
Published: February 2019

Purpose

This paper aims to explore the psychological motivations behind customers’ engagement with the brands and further investigate the effect of brand engagement on brand attachment and brand loyalty.

Design/methodology/approach

The theoretical model is tested with the data collected from 282 brand community members during offline brand community events, and structural equation modeling technique is used for statistical analysis.

Findings

The results indicate that brand psychological ownership and value-congruity act as important psychological motivations for customers to engage with the brands. A sense of brand attachment mediates the relationship between brand engagement and brand loyalty.

Research limitations/implications

Current study was conducted on a single brand community. Future research testing and validating the proposed model for multiple brands across different product categories is suggested for the generalization of current study results. The identification and validation of psychological drivers of engagement can have major implications on the ongoing research on customer engagement concept.

Practical implications

An effectively instilled sense of psychological ownership and value similarity notion in customers can help managers in engaging customers and capitalize on their repurchases and recommendations along with their attachment to the brands.

Originality/value

The study is unique in terms of the brand engagement model depicting the psychological antecedents to engagement with the brands and identifying the mediating role of brand attachment between brand engagement and behavioral loyalty.
Pushing for partnership: physician engagement and resistance in primary care renewal
Authors: Kreindler Sara A. , Struthers Ashley , Metge Colleen J. , Charette Catherine , Harlos Karen , Beaudin Paul , Bapuji Sunita B. , Botting Ingrid , Francois Jose
Published: February 2019

Purpose

Healthcare policymakers and managers struggle to engage private physicians, who tend to view themselves as independent of the system, in new models of primary care. The purpose of this paper is to examine this issue through a social identity lens.

Design/methodology/approach

Through in-depth interviews with 33 decision-makers and 31 fee-for-service family physicians, supplemented by document review and participant observation, the authors studied a Canadian province’s early efforts to engage physicians in primary care renewal initiatives.

Findings

Recognizing that the existing physician–system relationship was generally distant, decision-makers invested effort in relationship-building. However, decision-makers’ rhetoric, as well as the design of their flagship initiative, evinced an attempt to proceed directly from interpersonal relationship-building to the establishment of formal intergroup partnership, with no intervening phase of supporting physicians’ group identity and empowering them to assume equal partnership. The invitation to partnership did not resonate with most physicians: many viewed it as an inauthentic offer from an out-group (“bureaucrats”) with discordant values; others interpreted partnership as a mere transactional exchange. Such perceptions posed barriers to physician participation in renewal activities.

Practical implications

The pursuit of a premature degree of intergroup closeness can be counterproductive, heightening physician resistance.

Originality/value

This study revealed that even a relatively subtle misalignment between a particular social identity management strategy and its intergroup context can have highly problematic ramifications. Findings advance the literature on social identity management and may facilitate the development of more effective engagement strategies.