bluuebunny/crossref_metadata_2025 huggingface dataset:
CD147 Promotes Entry of Pentamer-Expressing Human Cytomegalovirus into Epithelial and Endothelial Cells
Authors: Vanarsdall Adam L. , Pritchard Sarah R. , Wisner Todd W. , Liu Jing , Jardetzky Ted S. , Johnson David C.
Published: May 2018

Human cytomegalovirus (HCMV) replicates in many diverse cell types
in vivo
, and entry into different cells involves distinct entry mechanisms and different envelope glycoproteins. HCMV glycoprotein gB is thought to act as the virus fusogen, apparently after being triggered by different gH/gL proteins that bind distinct cellular receptors or entry mediators. A trimer of gH/gL/gO is required for entry into all cell types, and entry into fibroblasts involves trimer binding to platelet-derived growth factor receptor alpha (PDGFRα). HCMV entry into biologically relevant epithelial and endothelial cells and monocyte-macrophages also requires a pentamer, gH/gL complexed with UL128, UL130, and UL131, and there is evidence that the pentamer binds unidentified receptors. We screened an epithelial cell cDNA library and identified the cell surface protein CD147, which increased entry of pentamer-expressing HCMV into HeLa cells but not entry of HCMV that lacked the pentamer. A panel of CD147-specific monoclonal antibodies inhibited HCMV entry into epithelial and endothelial cells, but not entry into fibroblasts. shRNA silencing of CD147 in endothelial cells inhibited HCMV entry but not entry into fibroblasts. CD147 colocalized with HCMV particles on cell surfaces and in endosomes. CD147 also promoted cell-cell fusion induced by expression of pentamer and gB in epithelial cells. However, soluble CD147 did not block HCMV entry and trimer and pentamer did not bind directly to CD147, supporting the hypothesis that CD147 acts indirectly through other proteins. CD147 represents the first HCMV entry mediator that specifically functions to promote entry of pentamer-expressing HCMV into epithelial and endothelial cells.

IMPORTANCE
Human cytomegalovirus infects nearly 80% of the world’s population and causes significant morbidity and mortality. The current method of treatment involves the use of antiviral agents that are prone to resistance and can be highly toxic to patients; currently, there is no vaccine against HCMV available. HCMV infections involve virus dissemination throughout the body, infecting a wide variety of tissues; however, the mechanism of spread is not well understood, particularly with regard to which cellular proteins are utilized by HCMV to establish infection. This report describes the characterization of a newly identified cellular molecule that affects HCMV entry into epithelial and endothelial cells. These results will lead to a better understanding of HCMV pathogenesis and have implications for the development of future therapeutics.
Ceftazidime Is the Key Diversification and Selection Driver of VIM-Type Carbapenemases
Authors: Martínez-García Laura , González-Alba José M. , Baquero Fernando , Cantón Rafael , Galán Juan Carlos
Published: May 2018

In recent decades, carbapenems have been considered the last line of antibiotic therapy for Gram-negative bacterial infections. Unfortunately, strains carrying a high diversity of β-lactamases able to hydrolyze carbapenems have emerged in the clinical setting. Among them, VIM β-lactamases have diversified in a bloom of variants. The evolutionary reconstructions performed in this work revealed that, at the end of the 1980s, two independent events involving diversification from VIM-2 and VIM-4 produced at least 25 VIM variants. Later, a third event involving diversification from VIM-1 occurred in the mid-1990s. In a second approach to understanding the emergence of VIM carbapenemases, 44 mutants derived from VIM-2 and VIM-4 were obtained by site-directed mutagenesis based on those positions predicted to be under positive selection. These variants were expressed in an isogenic context. The more-evolved variants yielded increased levels of hydrolytic efficiency toward ceftazidime to a higher degree than toward carbapenems. In fact, an antagonist effect was frequently observed. These results led us to develop an experimental-evolution step. When
Escherichia coli
strains carrying VIM-2 or VIM-4 were submitted to serial passages at increasing concentrations of carbapenems or ceftazidime, more-efficient new variants (such as VIM-11 and VIM-1, with N165S [bearing a change from N to S at position 165] and R228S mutations, respectively) were only obtained when ceftazidime was present. Therefore, the observed effect of ceftazidime in the diversification and selection of VIM variants might help to explain the recent bloom of carbapenemase diversity, and it also represents another example of the potential universal effect exerted by ceftazidime in the selection of more-efficient β-lactamase variants, as in TEM, CTX-M, or KPC enzymes.

IMPORTANCE
One of the objectives recently proposed by the World Health Organization (WHO) Assembly in the global plan on antimicrobial resistance was to improve the understanding and knowledge of antimicrobial resistance. In the present work, we paid attention to the drivers of diversification and selection of new carbapenemases in Gram-negative bacteria, which occupy one of the most critical places in the WHO priority list of antibiotic-resistant microorganisms. Based on evolutionary-reconstruction, site-directed-mutagenesis, and experimental-evolution approaches, we proposed a critical role of ceftazidime exposure in the selection of VIM carbapenemase variants. This surprising finding is also applicable to other β-lactamases, indicating that ceftazidime, and not other antibiotics, might have a universal effect in the diversification of β-lactamases. Our results might help to define future strategies to reconsider the extended use of ceftazidime.
Rise and fall of the eosinophils in heart failure: a rare but important phenomenon seen with cardiomyopathy
Authors: Ali Danish , Snead David , Dhakshinamurthy Vijay Anand , Banerjee Prithwish
Published: May 2018

A 65-year-old lady and a 69-year-old gentleman, both with a background history of adult-onset asthma, presented with clinical features of heart failure (HF). High-sensitivity cardiac troponin T and eosinophils were significantly raised, along with poor left ventricular (LV) systolic function on cardiac imaging. Endocardial and skin biopsy (in cases 1 and 2, respectively) showed eosinophilic infiltration. This in combination with the clinical features confirmed the diagnosis of eosinophilic myocarditis (EM) secondary to eosinophilic granulomatosis with polyangiitis in case 1. Both cases were managed with high-dose intravenous corticosteroids and conventional HF medication. Case 1 successfully responded clinically with improvement in LV systolic function. Case 2 required further immunosuppressive therapy (rituximab) and cardiac resynchronisation therapy, but eventually died of septic shock secondary to immunosuppressives. Our cases highlight the importance of early diagnosis and treatment of EM and ongoing monitoring of patients on immunosuppressive therapy.
Impact of measles supplementary immunisation activities on utilisation of maternal and child health services in low-income and middle-income countries
Authors: Postolovska Iryna , Helleringer Stéphane , Kruk Margaret E , Verguet Stéphane
Published: May 2018

Background

Measles supplementary immunisation activities (SIAs) are an integral component of measles elimination in low-income and middle-income countries (LMICs). Despite their success in increasing vaccination coverage, there are concerns about their negative consequences on routine services. Few studies have conducted quantitative assessments of SIA impact on utilisation of health services.

Methods

We analysed the impact of SIAs on utilisation of selected maternal and child health services using Demographic and Health Surveys and Multiple Indicator Cluster Surveys from 28 LMICs, where at least one SIA occurred over 2000–2014. Logistic regressions were conducted to investigate the association between SIAs and utilisation of the following services: facility delivery, postnatal care and outpatient sick child care (for fever, diarrhoea, cough).

Results

SIAs do not appear to significantly impact utilisation of maternal and child services. We find a reduction in care-seeking for treatment of child cough (OR 0.67; 95% CI 0.48 to 0.95); and a few significant effects at the country level, suggesting the need for further investigation of the idiosyncratic effects of SIAs in each country.

Conclusion

The paper contributes to the debate on vertical versus horizontal programmes to ensure universal access to vaccination. Measles SIAs do not seem to affect care-seeking for critical conditions.
Study of the measurement and predictive validity of the Functional Movement Screen
Authors: Philp Fraser , Blana Dimitra , Chadwick Edward K , Stewart Caroline , Stapleton Claire , Major Kim , Pandyan Anand D
Published: May 2018

Objective

The aim of the study was to evaluate the reported measurement capabilities and predictive validity of the Functional Movement Screen (FMS) for injury.

Methods

This was a prospective observational longitudinal study of 24 male footballers from a single team in England, alongside analysis of an existing database over one season (September 2015–May 2016). A preseason FMS was carried out with scores recorded by an experienced assessor and derived, retrospectively, from the three-dimensional movement data that were simultaneously captured. The assessor scores were compared with the photogrammetric system to determine measurement validity, and predictive validity was quantified by assessing sensitivity and specificity (cut-off score of 14).

Results

The real-time assessor score matched the photogrammetric score awarded for one of the participants, was higher than the photogrammetric system for 22 participants and was lower than the photogrammetric system in 1 participant. There was no discernible relationship between FMS scores and the competencies required to be met as per the rules articulated for the allocation of a score. A higher number of total injuries were associated with higher FMS scores, whether determined through real-time assessment or codification of kinematic variables. Additionally, neither method of score determination was able to prospectively identify players at risk of serious injury.

Conclusion

The FMS does not demonstrate the properties essential to be considered as a measurement scale and has neither measurement nor predictive validity. A possible reason for these observations could be the complexity in the instructions associated with the scale. Further work on eliminating redundancies and improving the measurement properties is recommended.
Bioprosthetic aortic valve durability in the era of transcatheter aortic valve implantation
Authors: Salaun Erwan , Clavel Marie-Annick , Rodés-Cabau Josep , Pibarot Philippe
Published: May 2018

The main limitation of bioprosthetic valves is their limited durability, which exposes the patient to the risk of aortic valve reintervention. Transcatheter aortic valve implantation (TAVI) is considered a reasonable alternative to surgical aortic valve replacement (SAVR) in patients with intermediate or high surgical risk. TAVI is now rapidly expanding towards the lower risk populations. Although the results of midterm durability of the transcatheter bioprostheses are encouraging, their long-term durability remains largely unknown. The objective of this review article is to present the definition, mechanisms, incidence, outcome and management of structural valve deterioration of aortic bioprostheses with specific emphasis on TAVI. The structural valve deterioration can be categorised into three stages: stage 1: morphological abnormalities (fibrocalcific remodelling and tear) of bioprosthesis valve leaflets without hemodynamic valve deterioration; stage 2: morphological abnormalities and moderate hemodynamic deterioration (increase in gradient and/or new onset of transvalvular regurgitation); and stage 3: morphological abnormalities and severe hemodynamic deterioration. Several specifics inherent to the TAVI including valve oversizing, manipulation, delivery, positioning and deployment may cause injuries to the valve leaflets and increase leaflet mechanical stress, which may limit the long-term durability of transcatheter bioprostheses. The selection of the type of aortic valve replacement and bioprosthesis should thus take into account the ratio between the demonstrated durability of the bioprostheses versus the life expectancy of the patient. Pending the publication of robust data on long-term durability of transcatheter bioprostheses, it appears reasonable to select SAVR with a bioprosthesis model that has well-established long-term durability in patients with low surgical risk and long life expectancy.
Reported fire safety and first-aid amenities in Airbnb venues in 16 American cities
Authors: Kennedy Hudson R , Jones Vanya C , Gielen Andrea
Published: May 2018

Airbnb helps hosts rent all or part of their home to guests as an alternative to traditional hospitality settings. Airbnb venues are not uniformly regulated across the USA. This study quantified the reported prevalence of fire safety and first-aid amenities in Airbnb venues in the USA. The sample includes 120 691 venues in 16 US cities. Proportions of host-reported smoke and carbon monoxide (CO) detectors, fire extinguishers and first-aid kits were calculated. The proportion of venues that reportedly contained amenities are as follows: smoke detectors 80% (n=96 087), CO detectors 57.5% (n=69 346), fire extinguishers 42% (n=50 884) and first-aid kits 36% (n=43 497). Among this sample of Airbnb venues, safety deficiencies were noted. While most venues had smoke alarms, approximately 1/2 had CO alarms and less than 1/2 reported having a fire extinguishers or first-aid kits. Local and state governments or Airbnb must implement regulations compliant with current National Fire Protection Association fire safety standards.
Years of life lost due to encounters with law enforcement in the USA, 2015–2016
Authors: Bui Anthony L , Coates Matthew M , Matthay Ellicott C
Published: May 2018

Background

To inform discussions on rates, burden and priority-setting in relation to police violence, we quantified the number and rate of years of life lost (YLLs) due to police violence by race/ethnicity and age in the USA, 2015–2016.

Methods

We used data on the number of deaths due to police violence from ‘The Counted’, a media-based source compiled byThe Guardian. YLLs are the difference between an individual’s age at death and their corresponding standard life expectancy at age of death.

Results

There were 57 375 and 54 754 YLLs due to police violence in 2015 and 2016, respectively. People of colour comprised 38.5% of the population, but 51.5% of YLLs. YLLs were greatest among those aged 25–34 years, and the number of YLLs at younger ages was greater among people of colour than whites.

Conclusions

The number of YLLs due to police violence is substantial. YLLs highlight that police violence disproportionately impacts young people, and the young people affected are disproportionately people of colour. Framing police violence as an important cause of deaths among young adults provides another valuable lens to motivate prevention efforts.
Cognitive-behavioural therapy does not meaningfully reduce depression in most people with epilepsy: a systematic review of clinically reliable improvement
Authors: Noble Adam J , Reilly James , Temple James , Fisher Peter L
Published: May 2018

Psychological treatment is recommended for depression and anxiety in those with epilepsy. This review used standardised criteria to evaluate, for the first time, the clinical relevance of any symptom change these treatments afford patients. Databases were searched until March 2017 for relevant trials in adults. Trial quality was assessed and trial authors asked for individual participants’ pre-treatment and post-treatment distress data. Jacobson’s methodology determined the proportion in the different trial arms demonstrating reliable symptom change on primary and secondary outcome measures and its direction. Search yielded 580 unique articles; only eight eligible trials were identified. Individual participant data for five trials—which included 398 (85%) of the 470 participants randomised by the trials—were received. The treatments evaluated lasted ~7 hours and all incorporated cognitive-behavioural therapy (CBT). Depression was the primary outcome in all; anxiety a secondary outcome in one. On average, post-treatment assessments occurred 12 weeks following randomisation; 2 weeks after treatment had finished. There were some limitations in how trials were conducted, but overall trial quality was ‘good’. Pooled risk difference indicated likelihood of reliable improvement in depression symptoms was significantly higher for those randomised to CBT. The extent of gain was though low—the depressive symptoms of most participants (66.9%) receiving CBT were ‘unchanged’ and 2.7% ‘reliably deteriorated’. Only 30.4% made a ‘reliable improvement. This compares with 10.2% of participants in the control arms who ‘reliably improved’ without intervention. The effect of the treatments on secondary outcome measures, including anxiety, was also low. Existing CBT treatments appear to have limited benefit for depression symptoms in epilepsy. Almost 70% of people with epilepsy do not reliably improve following CBT. Only a limited number of trials have though been conducted in this area and there remains a need for large, well-conducted trials.
Systematic review of fit note use for workers in the UK
Authors: Dorrington Sarah , Roberts Emmert , Mykletun Arnstein , Hatch Stephani , Madan Ira , Hotopf Matthew
Published: May 2018

Objectives

The fit note, introduced in England, Wales and Scotland in 2010, was designed to change radically the sickness certification process from advising individuals on their inability to work to advising them on what they could do if work could be adapted. Our review aimed to evaluate the following: (1) Is the ‘maybe fit’ for work option being selected for patients? (2) Are work solutions being recommended? (3) Has the fit note increased return to work? (4) Has the fit note reduced the length of sickness absence? We considered the way in which outcomes vary according to patient demographics including type of health problem.

Methods

Studies were identified by a systematic search. We included all studies of any design conducted in the UK with working age adults, aged 16 or over, from 1 April 2010 to 1 Nov 2017. Risk of bias was assessed using a modified Newcastle-Ottawa Scale.

Results

Thirteen papers representing seven studies met inclusion criteria. In the largest study, ‘maybe fit’ for work was recommended in 6.5% of fit notes delivered by general practitioners (GP; n=361 801) between April 2016 and March 2017. ‘Maybe fit’ recommendations were made in 8.5%–10% of fit notes received by primary care patients in employment, and in 10%–32% of patients seen by GPs trained in the Diploma in Occupational Medicine. ‘Maybe fit’ was recommended more for women, those with higher socioeconomic status, and for physical, as opposed to psychiatric disorders. The majority of fit notes with the ‘maybe fit’ option selected included work solutions. There was inconclusive evidence to suggest that the introduction of the fit note has reduced sickness absence among patients in employment.

Conclusions

Fit notes represent a major shift in public policy. Our review suggests that they have been incompletely researched and not implemented as intended.
Primary extraskeletal chondrosarcoma in the axillary region of a dog with review of the literature
Authors: Pennington Catrina , Monne Rodriguez Josep , Finck Marlene , Walton Ben
Published: May 2018

An eight‐year‐old, intact male English springer spaniel was presented with a five‐month history of right forelimb lameness. MRI revealed a right axillary mass with associated nerve root thickening. Radiographs showed no evidence of bone involvement or pulmonary metastasis. A biopsy was taken of the mass, and histopathological examination was consistent with a high‐grade chondrosarcoma. Conservative treatment was elected, and the patient euthanased four months later, after which postmortem examination was performed.
The impact of sedentary and physical activity behaviour on frailty in middle-aged and older adults
Authors: Kehler Dustin Scott
Published: May 2018

Physical activity and sedentary behaviours are associated with frailty. However, it is unknown if different accumulation patterns of these behaviours are linked with frailty. Four studies were conducted: the first 3 determined if bouts of moderate–vigorous physical activity (MVPA) and patterns of sedentary behaviours were associated with frailty (study 1), and if sex (study 2) and cardiovascular disease (CVD) status (study 3) affected these associations. Study 4 systematically reviewed the evidence to determine if preoperative physical activity and sedentary behaviours were linked to postcardiac surgical outcomes. Studies 1–3 used accelerometer data from the 2003–2004/2005–2006 National Health and Nutrition Examination Survey. Bouted (≥10 min) and sporadic (<10 min) durations of MVPA were analyzed based on meeting a proportion of the physical activity guidelines of 150 min/week. Prolonged sedentary behaviours were measured in bouts lasting ≥30 min. Breaks from sedentary behaviour were any ≥1 min interruption in sedentary time. Average intensity and duration during breaks were analyzed. Frailty was measured with a 46-item frailty index (FI). Study 4 included investigations that linked preoperative physical activity behaviours to postoperative health outcomes. The first 3 studies revealed that sporadic and bouted MVPA were associated with a lower FI. Meeting 1%–49% of the physical activity guidelines had a protective association with frailty. Prolonged sedentary bouts had a more detrimental association with frailty in females than males. Bouted MVPA was associated with a lower FI in CVD participants but not in those without CVD. Average break intensity was associated with a lower FI across studies. Average break duration was associated with frailty in males and in those with CVD. Study 4 included 11 articles, which reported inconsistent findings in relation to self-reported physical activity behaviour and postoperative outcomes in cardiac surgery patients. No studies analyzed sedentary behaviour or frailty. Data from this thesis suggest that bouts of MVPA and patterns of sedentary behaviours are associated with frailty, and support the need to limit extended periods of sedentary time and promote a physically active lifestyle. Studies are needed to determine if preoperative physical activity and sedentary behaviours are associated with postcardiac surgical frailty.
A novel MS3 experiment for quantifying ions with a linear ion trap
Authors: Campbell J. Larry , Collings Bruce A. , Le Blanc J.C. Yves , Hager James W.
Published: May 2018

Liquid chromatography coupled with tandem mass spectrometry has long been employed for the quantitation of molecules. With judicious selection of precursor and fragment ions, multiple-reaction monitoring assays can be developed rapidly for these experiments. However, there are cases where analyses struggle due to high background signals caused by matrix effects that interfere with the analytical signal. An alternative to MRMs involves using two stages of tandem mass spectrometry — an MS3 experiment. Although this technique can provide greater selectivity than MS/MS experiments, cycle times for MS3 experiments are typically longer than MRM-type experiments. Here, we present a quantitation technique employing an MS3 method with shorter cycle times than traditional linear ion trap MS3 scans. Termed “scan-free” MS3, this technique performs “mass analysis” by isolating the ions of interest in the linear ion trap and then emptying the trap of these ions. The signal will be due only to those preselected ions, resulting in an MS3 experiment with up to a ∼35% reduction in cycle times relative to standard MS3 experiments without loss of sensitivity. We compare the analytical performance of this method with MRMs, as well as standard MS3 experiments, finding equivalent or better performance from the scan-free MS3 method.
Further studies on the 1988MW5.9 Saguenay, Quebec, earthquake sequence
Authors: Ma Shutian , Motazedian Dariush , Lamontagne Maurice
Published: May 2018

Many small earthquakes occur annually in Eastern Canada, but moderate to strong earthquakes are infrequent. The 25 November 1988 MW5.9 Saguenay mainshock remains the largest earthquake in the last 80 years in eastern North America. In this article, some aspects of that earthquake sequence were re-analyzed using several modern methods. The regional depth-phase modeling procedure was used to refine the focal depths for the foreshock, the aftershocks, and other MN≥ 2.5 regional earthquakes. The hypocenters of 10 earthquakes were relocated using hypoDD. The spatial distribution of eight relocated hypocenters defines the rupture plane of the mainshock. The moment tensor for the mainshock was retrieved using three-component long-period surface wave records at station HRV (Harvard seismograph station) with additional constraints from P-wave polarities. One nodal plane is conclusively identified to be close to the rupture plane, and its strike is similar to the trend of the south wall of the Saguenay Graben. Based on the consistency between the strike of the nodal plane and the trend of the Graben, as well as the deep focal depth distribution, we suggest that the Saguenay earthquake sequence is related to the reactivation of one of the faults of the Saguenay Graben.
A scheme for preparing cluster state with nitrogen-vacancy centers and microtoroidal resonator coupled systems
Authors: Yu Li-Zhi , Wu Tao
Published: May 2018

Quantum entanglement is a key resource in quantum information processing. In this paper, we propose a scheme for preparing a cluster entangled state by means of multiple nitrogen vacancy centers and microtoroidal resonator coupled systems. The scheme employs an input–output process and single-photon interference, without any other auxiliary entanglement particles or classical communication. Considering the current experimental technology, the scheme will be implemented and has an important role in the preparation of cluster entangled state by means of nitrogen vacancy centers and microtoroidal resonator coupled systems.
Genetic mapping and a new PCR-based marker linked to a dwarfing gene in oat (Avena sativa L.)
Authors: Zhao Jun , Tang Xueqin , Wight Charlene P. , Tinker Nicholas A. , Jiang Yunfeng , Yan Honghai , Ma Jian , Lan Xiujin , Wei Yuming , Ren Changzhong , Chen Guoyue , Peng Yuanying
Published: May 2018

Short straw is a desired trait in cultivated hexaploid oat (Avena sativa L.) for some production environments. Marker-assisted selection, a key tool for achieving this objective, is limited by a lack of mapping data and available markers. Here, bulked-segregant analysis was used to identify PCR-based markers associated with a dwarfing gene. Genetic analysis identified a monogenic dominant inheritance of one dwarfing gene from WAOAT2132, temporarily designated DwWA. A simple sequence repeat (SSR) marker (AME117) that was already available and a new codominant PCR-based marker (bi17) developed by homologous cloning in the present study were both associated with the dwarfing gene. The two markers were located 21 and 1.2 cM from DwWA, respectively. The bi17 marker was mapped to neighboring SNP markers on chromosome 18D of the oat consensus map. Since Dw6 was previously mapped on chromosome 18, and since our new marker bi17 is also diagnostic for NILs generated for Dw6, there is strong evidence that the dwarfing gene identified in WAOAT2132 is Dw6. The newly developed markers could find applications in the identification of this gene in oat germplasm and in the fine mapping or positional cloning of the gene.
Quantum field-theoretical description of neutrino and neutral kaon oscillations
Authors: Volobuev Igor P.
Published: May 2018

It is shown that the neutrino and neutral kaon oscillation processes can be consistently described in quantum field theory using only plane waves of the mass eigenstates of neutrinos and neutral kaons. To this end, the standard perturbative S-matrix formalism is modified so that it can be used for calculating the amplitudes of the processes passing at finite distances and finite time intervals. The distance-dependent and time-dependent parts of the amplitudes of the neutrino and neutral kaon oscillation processes are calculated and the results turn out to be in accordance with those of the standard quantum mechanical description of these processes based on the notion of neutrino flavor states and neutral kaon states with definite strangeness. However, the physical picture of the phenomena changes radically: now, there are no oscillations of flavor or definite strangeness states, but, instead of it, there is interference of amplitudes due to different virtual mass eigenstates.
Charged anti-de Sitter BTZ black holes in Maxwell-f(T) gravity
Authors: Nashed G. G. L. , Capozziello S.
Published: May 2018

Inspired by the Bañados, Teitelboim and Zanelli (BTZ) formalism, we discuss the Maxwell-[Formula: see text] gravity in [Formula: see text] dimensions. The main task is to derive exact solutions for a special form of [Formula: see text], with [Formula: see text] being the torsion scalar of Weitzenböck geometry. To this end, a triad field is applied to the equations of motion of charged [Formula: see text] and sets of circularly symmetric noncharged and charged solutions have been derived. We show that, in the charged case, the monopole-like and the [Formula: see text] terms are linked by a correlative constant despite the known results in teleparallel geometry and its extensions.[Formula: see text] Furthermore, it is possible to show that the event horizon is not identical with the Cauchy horizon due to such a constant. The singularities and the horizons of these black holes are examined: they are new and have no analogue in the literature due to the fact that their curvature singularities are soft. We calculate the energy content of these solutions by using the general vector form of the energy–momentum within the framework of [Formula: see text] gravity. Finally, some thermodynamical quantities, like entropy and Hawking temperature, are derived.
E11, brane dynamics and duality symmetries
Authors: West Peter
Published: May 2018

Following arXiv:hep-th/0412336 we use the nonlinear realisation of the semi-direct product of [Formula: see text] and its vector representation to construct brane dynamics. The brane moves through a space-time which arises in the nonlinear realisation from the vector representation and it contains the usual embedding coordinates as well as the worldvolume fields. The resulting equations of motion are first order in derivatives and can be thought of as duality relations. Each brane carries the full [Formula: see text] symmetry and so the Cremmer–Julia duality symmetries. We apply this theory to find the dynamics of the IIA and IIB strings, the M2 and M5 branes, the IIB D3 brane as well as the one and two branes in seven dimensions.
Pitching effect on transonic wing stall of a blended flying wing with low aspect ratio
Authors: Tao Yang , Zhao Zhongliang , Wu Junqiang , Fan Zhaolin , Zhang Yi
Published: May 2018

Numerical simulation of the pitching effect on transonic wing stall of a blended flying wing with low aspect ratio was performed using improved delayed detached eddy simulation (IDDES). To capture the discontinuity caused by shock wave, a second-order upwind scheme with Roe’s flux-difference splitting is introduced into the inviscid flux. The artificial dissipation is also turned off in the region where the upwind scheme is applied. To reveal the pitching effect, the implicit approximate-factorization method with sub-iterations and second-order temporal accuracy is employed to avoid the time integration of the unsteady Navier–Stokes equations solved by finite volume method at Arbitrary Lagrange–Euler (ALE) form. The leading edge vortex (LEV) development and LEV circulation of pitch-up wings at a free-stream Mach number M = 0.9 and a Reynolds number Re = [Formula: see text] is studied. The Q-criterion is used to capture the LEV structure from shear layer. The result shows that a shock wave/vortex interaction is responsible for the vortex breakdown which eventually causes the wing stall. The balance of the vortex strength and axial flow, and the shock strength, is examined to provide an explanation of the sensitivity of the breakdown location. Pitching motion has great influence on shock wave and shock wave/vortex interactions, which can significantly affect the vortex breakdown behavior and wing stall onset of low aspect ratio blended flying wing.
Wave dynamics in an extended macroscopic traffic flow model with periodic boundaries
Authors: Wang Yu-Qing , Chu Xing-Jian , Zhou Chao-Fan , Yan Bo-Wen , Jia Bin , Fang Chen-Hao
Published: May 2018

Motivated by the previous traffic flow model considering the real-time traffic state, a modified macroscopic traffic flow model is established. The periodic boundary condition is applied to the car-following model. Besides, the traffic state factor R is defined in order to correct the real traffic conditions in a more reasonable way. It is a key step that we introduce the relaxation time as a density-dependent function and provide corresponding evolvement of traffic flow. Three different typical initial densities, namely the high density, the medium one and the low one, are intensively investigated. It can be found that the hysteresis loop exists in the proposed periodic-boundary system. Furthermore, the linear and nonlinear stability analyses are performed in order to test the robustness of the system.
The q-deformed mKP hierarchy with two parameters
Authors: Tian Kelei , Ge Yanyan , Zhu Xiaoming
Published: May 2018

In this paper, with the help of the biparametric quantum calculus we construct the Sato theory on the q-deformation modified Kadomtsev–Petviashvili hierarchy with two parameters (qp-mKP), which is a new deformation of classical mKP hierarchy. The Lax equation and dressing operator of qp-mKP hierarchy are derived. By considering the M operator and [Formula: see text] operator, the additional symmetry of qp-mKP hierarchy is obtained.
Biclustering of Gene Expression Data Using Cuckoo Search and Genetic Algorithm
Authors: Yin Lu , Qiu Junlin , Gao Shangbing
Published: May 2018

Biclustering analysis of gene expression data can reveal a large number of biologically significant local gene expression patterns. Therefore, a large number of biclustering algorithms apply meta-heuristic algorithms such as genetic algorithm (GA) and cuckoo search (CS) to analyze the biclusters. However, different meta-heuristic algorithms have different applicability and characteristics. For example, the CS algorithm can obtain high-quality bicluster and strong global search ability, but its local search ability is relatively poor. In contrast to the CS algorithm, the GA has strong local search ability, but its global search ability is poor. In order to not only improve the global search ability of a bicluster and its coverage, but also improve the local search ability of the bicluster and its quality, this paper proposed a meta-heuristic algorithm based on GA and CS algorithm (GA-CS Biclustering, Georgia Association of Community Service Boards (GACSB)) to solve the problem of gene expression data clustering. The algorithm uses the CS algorithm as the main framework, and uses the tournament strategy and the elite retention strategy based on the GA to generate the next generation of the population. Compared with the experimental results of common biclustering analysis algorithms such as correlated correspondence (CC), fast, local clustering (FLOC), interior search algorithm (ISA), Securities Exchange Board of India (SEBI), sum of squares between (SSB) and coordinated scheduling/beamforming (CSB), the GACSB algorithm can not only obtain biclusters of high quality, but also obtain biclusters of high-biologic significance. In addition, we also use different bicluster evaluation indicators, such as Average Correlation Value (ACV), Mean-Squared Residue (MSR) and Virtual Error (VE), and verify that the GACSB algorithm has a strong scalability.
Reliability Modeling of SiC-Based Multiphase Synchronous Boost Converter
Authors: zaman Haider , Zheng Xiancheng , Ali Husan , Khan Shahbaz , Wu Xiaohua
Published: May 2018

Despite attractive thermal and electrical characteristics, wide band-gap semiconductor devices such as SiC MOSFET have struggled to penetrate in aircraft applications because of reliability issues in earlier releases. The second and third generation SiC MOSFETs have achieved improved reliability using high quality oxides and innovative fabrication process. This paper presents a failure rate model for SiC MOSFET based on the accelerated test data at a given operating condition. The proposed model enables the system level reliability analysis of second generation SiC MOSFET-based converters. The reliability of SiC two-phase synchronous boost converter has been evaluated at two different operating conditions: 10 and 16 A load condition. To predict the life time of the converter even after a chain of component failures, Markov’s reliability model of the converter is developed. The state transition probabilities and mean time to failure (MTTF) of SiC converter are compared against its Si counterpart which shows that second generation SiC MOSFETs are for aircraft applications with high reliability.
TRADING STRATEGIES WITHIN THE EDGES OF NO-ARBITRAGE
Authors: CARTEA ÁLVARO , JAIMUNGAL SEBASTIAN , RICCI JASON
Published: May 2018

We develop a trading strategy that employs limit and market orders in a multiasset economy where the assets are not only correlated, but can also be structurally dependent. To model the structural dependence, the mid-price processes follow a multivariate reflected Brownian motion on the closure of a no-arbitrage region which is dictated by the bid–ask spreads of the assets. We provide a mathematical framework for such an economy and solve for the value function and optimal control for an investor who takes positions in these assets. The optimal strategy exhibits two dominant features which depend on how far the vector of mid-prices is from the no-arbitrage bounds. When mid-prices are sufficiently far from the no-arbitrage edges, the strategy behaves as that of a market maker who posts buy and sell limit orders. And when the mid-price vector is close to the edge of the no-arbitrage region, the strategy executes a combination of market orders and limit orders to profit from statistical arbitrages. We discuss a numerical scheme to solve for the value function and optimal control, and perform a simulation study to discuss the main characteristics of the optimal strategy.
N-Doped Graphene Quantum Dots Using Different Bases
Authors: Naik M. Jaya Prakash , Mohanta Sourajit , Mandal Peetam , Saha Mitali
Published: May 2018

Photoluminescent graphene quantum dots (GQDs) have received tremendous attention due to their sui generis chemical, electronic and optical properties but fabricating the pristine quality of GQD is extremely challenging. Herein, we have reported the pyrolysis of citric acid which in the presence of different bases viz. triethylamine, ammonium hydroxide and urea, produced N-doped GQDs at different pH. The effect of different pH has been studied in detail to optimize the formation conditions of the GQD. Ultraviolet–visible (UV–Vis) spectroscopy and normalized fluorescence spectra were applied to analyze the optical properties of the GQD. The mean particle size was analyzed by a particle size analyzer (dynamic light dispersion).
Accurate prediction of human miRNA targets via graph modeling of the miRNA-target duplex
Authors: Mohebbi Mohammad , Ding Liang , Malmberg Russell L. , Momany Cory , Rasheed Khaled , Cai Liming
Published: May 2018

miRNAs are involved in many critical cellular activities through binding to their mRNA targets, e.g. in cell proliferation, differentiation, death, growth control, and developmental timing. Accurate prediction of miRNA targets can assist efficient experimental investigations on the functional roles of miRNAs. Their prediction, however, remains a challengeable task due to the lack of experimental data about the tertiary structure of miRNA-target binding duplexes. In particular, correlations of nucleotides in the binding duplexes may not be limited to the canonical Watson Crick base pairs (BPs) as they have been perceived; methods based on secondary structure prediction (typically minimum free energy (MFE)) have only had mix success. In this work, we characterized miRNA binding duplexes with a graph model to capture the correlations between pairs of nucleotides of an miRNA and its target sequences. We developed machine learning algorithms to train the graph model to predict the target sites of miRNAs. In particular, because imbalance between positive and negative samples can significantly deteriorate the performance of machine learning methods, we designed a novel method to re-sample available dataset to produce more informative data learning process.

We evaluated our model and miRNA target prediction method on human miRNAs and target data obtained from mirTarBase, a database of experimentally verified miRNA-target interactions. The performance of our method in target prediction achieved a sensitivity of 86% with a false positive rate below 13%. In comparison with the state-of-the-art methods miRanda and RNAhybrid on the test data, our method outperforms both of them by a significant margin.

The source codes, test sets and model files all are available at http://rna-informatics.uga.edu/?f=software&p=GraB-miTarget .
Business Modeling and Public Policy in High-Tech Industries: Exploratory Evidences from Two Brazilian Semiconductor Support Programs
Authors: Alves Alex da Silva , Botelho Antonio José Junqueira , Duarte Virgínia
Published: May 2018

This paper adopts an exploratory analysis based on a multiple case study to investigate the interplay of Small and Medium Enterprises (SMEs) business modeling strategies and Science, Technology and Innovation (STI) policies in a mid-income country efforts to develop a national semiconductor industry. Specifically, we analyze how 22 Brazilian SMEs supported by two comprehensive federal programs designed and implemented business models and strategies in an attempt to, on the one hand, meet the scope and timing of public funding resources and, on the other hand, develop capabilities to enter the industry’s global value chain. Drawing on a wide body of literature and on the evidence collected, we identified and categorized the firms’ business models into five groups: Pure Play IP, Pure Play Design, Fabless, Fabless Plus and Captive. We then analysed the firms’ within the specificities of each group. The paper shows that, in addition to business models and strategies oriented to meet short-term survival needs, the financial benefits for firms were low and unstable, with recurrent and unresolved frictions between policy-makers, planners and firms.
University–Industry Collaboration in Sri Lanka — A Developing Country Perspective
Authors: Wickramasinghe Vathsala , Malik Khaleel
Published: May 2018

Many advanced economies are at the forefront of the growth of university–industry (U–I) collaborations. But many developing countries have yet to fully implement this type of important linkage phenomenon. We report empirical findings from our study conducted in Sri Lanka to provide more explanations on the nature of U–I collaboration in developing countries. We used multiple methods to collect empirical data, namely a questionnaire survey, interviews with university academic staff and a few company managers, held focus group workshops and exploited secondary data on national government sponsorship initiatives linked to U–I collaborations. This paper discusses key practical implications around current modes of U–I collaborations, barriers to collaboration and funding of collaborations, which provide a number of valuable lessons for the advancement of knowledge.
Human Capital as Barrier to Innovation: Post-Transition Experience
Authors: Botrić Valerija , Božić Ljiljana
Published: May 2018

The paper addresses the question of human capital as constraint to innovation in post-transition economies. The analysis is performed both on the macroeconomic and microeconomic levels. Macroeconomic level encompasses discussion of available human capital and clustering of post-transition economies accordingly. Microeconomic analysis based on the Business Environment and Enterprise Performance Survey confirms that innovative firms are more likely to perceive inadequate education of the workforce as severe obstacle to their business activities. In all analyzed clusters, the more innovative employers feel compelled to train their employees, the more likely they are to be dissatisfied with the education of the workforce.
An Investigation of Culture and Contextual Performance in Projects: What is the Role of Project Leader Personal Style Differences?
Authors: Aronson Zvi H.
Published: May 2018

Can individual differences in the personal style of the leader contribute to project culture? How might culture boost behavioral outcomes and success in projects? Drawing on a sample of 189 participants in 59 projects, we illustrate that leader personal style plays a part in the development of culture in project-based work. Additionally, we show that culture in projects can be exercised by the leader to initiate contextual performance — when workers willingly exert extra effort during project implementation. Finally, we show that contextual performance contributes to project success. Recommendations for selecting and coaching persons designated as project leaders are provided.
Project Portfolio Management Best Practice and Implementation: A South African Perspective
Authors: Oostuizen Chiara , Grobbelaar Sara S. , Bam Wouter G.
Published: May 2018

This paper analyses the link between project portfolio management (PPM) implementation and perceived company success in achieving strategic objectives. As foundation for a conceptual model, the paper explores and investigates three areas of PPM literature: (1) PPM success criteria (2) PPM success factors and (3) problems faced in PPM. Using a conceptual model, the paper empirically investigates the link between the implementation of various PPM practices, the perceived importance of these practices and the perceived success of project portfolios within a South African context. A mixed methodology approach consisting of: (1) surveys and (2) follow-up interviews was followed during the execution of the study. The study targeted 10 different industries and obtained 342 responses in total. The survey data was supported by four semi-structured follow-up interviews that aimed to further investigate some of the salient trends observed in the data. The study enables the deduction of various recommendations for good practice and implementation gaps in the area of PPM in the South African context. This includes recommendations regarding practices that appear to have a strong link with perceived PPM success, yet are viewed as unimportant by many practitioners.
Label-Free Fluorescent Detection of Hg2+ in Aqueous Media Based on N-Doped MoS2 Nanosheets
Authors: Liu Jing , Li Xiao , Gong Xin , Qing Taiping , Zhang Peng , Feng Bo
Published: May 2018

The incorporation of dopant atoms alters the structure of MoS2, resulting in unique properties and practical applications. Herein, a facile and low-cost approach for producing N-doped molybdenum disulfide (N-MoS[Formula: see text] was carried out using melamine and MoS2 in a laboratory tube furnace at 400[Formula: see text]C for 2[Formula: see text]h. The N-MoS2 fluorescent probe showed sensitive response to Hg[Formula: see text] in a wide concentration range of 0.4–10[Formula: see text][Formula: see text]M with a low limit of 28[Formula: see text]nM. The practical applicability of detecting Hg[Formula: see text] in lake water samples may open a new way to evaluate Hg[Formula: see text] in wastewater.