bluuebunny/crossref_metadata_2025 huggingface dataset:
A Re-Evaluation of Fixed Effect(s) Meta-Analysis
Authors: Rice Kenneth , Higgins Julian P. T. , Lumley Thomas
Published: March 2017

Meta-analysis is a common tool for synthesizing results of multiple studies. Among methods for performing meta-analysis, the approach known as ‘fixed effects’ or ‘inverse variance weighting’ is popular and widely used. A common interpretation of this method is that it assumes that the underlying effects in contributing studies are identical, and for this reason it is sometimes dismissed by practitioners. However, other interpretations of fixed effects analyses do not make this assumption, yet appear to be little known in the literature. We review these alternative interpretations, describing both their strengths and their limitations. We also describe how heterogeneity of the underlying effects can be addressed, with the same minimal assumptions, through either testing or meta-regression. Recommendations for the practice of meta-analysis are given; it is hoped that these will foster more direct connection of the questions that meta-analysts wish to answer with the statistical methods they choose.
Orientation and characterization of immobilized antibodies for improved immunoassays (Review)
Authors: Welch Nicholas G. , Scoble Judith A. , Muir Benjamin W. , Pigram Paul J.
Published: March 2017

Orientation of surface immobilized capture proteins, such as antibodies, plays a critical role in the performance of immunoassays. The sensitivity of immunodiagnostic procedures is dependent on presentation of the antibody, with optimum performance requiring the antigen binding sites be directed toward the solution phase. This review describes the most recent methods for oriented antibody immobilization and the characterization techniques employed for investigation of the antibody state. The introduction describes the importance of oriented antibodies for maximizing biosensor capabilities. Methods for improving antibody binding are discussed, including surface modification and design (with sections on surface treatments, three-dimensional substrates, self-assembled monolayers, and molecular imprinting), covalent attachment (including targeting amine, carboxyl, thiol and carbohydrates, as well as “click” chemistries), and (bio)affinity techniques (with sections on material binding peptides, biotin-streptavidin interaction, DNA directed immobilization, Protein A and G, Fc binding peptides, aptamers, and metal affinity). Characterization techniques for investigating antibody orientation are discussed, including x-ray photoelectron spectroscopy, spectroscopic ellipsometry, dual polarization interferometry, neutron reflectometry, atomic force microscopy, and time-of-flight secondary-ion mass spectrometry. Future perspectives and recommendations are offered in conclusion.
Modification of Schottky barrier properties of Al/p-type Si Schottky rectifiers with graphene-oxide-doped poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) interlayer
Authors: Janardhanam Vallivedu , Jyothi Inapagundla , Yuk Shim-Hoon , Choi Chel-Jong , Yun Hyung-Joong , Won Jonghan , Hong Won-Gi , Lee Sung-Nam , Rajagopal Reddy Varra
Published: March 2017

The effects of graphene-oxide (GO) doping in the poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) interlayer on the electrical and chemical properties of Al/p-type Si Schottky diodes were demonstrated. GO concentrations of 0.05 and 0.1 wt. % were used in the interlayer. The barrier height of the Al/p-type Si Schottky diode with a GO-doped PEDOT:PSS interlayer was higher than that of the diode with the pristine PEDOT:PSS interlayer; ultraviolet photoelectron spectroscopy measurements indicated that this could be well correlated with variations in the hole-injection barrier between the PEDOT:PSS interlayer and Al film caused by GO doping. The addition of 0.05 wt. % GO to the PEDOT:PSS interlayer increased the PEDOT to PSS ratio, resulting in an increase in conductivity. However, the conductivity of the PEDOT:PSS doped with 0.1 wt. % GO decreased; x-ray photoelectron spectroscopy results indicated that this could be attributed to the increased insulating GO content in PEDOT:PSS. At higher forward bias, an analysis of the forward log I–log V plot of the Al/p-type Si Schottky diodes with pristine and GO-doped PEDOT:PSS interlayers revealed different space-charge-limited current-transport mechanisms, which could be associated with additional traps originating from the GO.
Automated acoustic analysis of 50-kHz ultrasonic vocalizations using template matching and contour analysis
Authors: Barker David J. , Johnson Aaron M.
Published: March 2017

Ultrasonic vocalizations are a useful tool for inferring affective states in the rat and have been incorporated in research paradigms modeling important human conditions. While the majority of studies report the quantity or rate of observed ultrasonic vocalizations, growing evidence suggests that critical data may be contained in the acoustic features of individual vocalizations. Thus, the goal of the present study was to develop and validate a method for measuring acoustic parameters of ultrasonic vocalizations that were collected using automatic template detection. Acoustic parameters derived using this method were found to be comparable to those collected using commercially available software.
Iterative solution to bulk wave propagation in polycrystalline materials
Authors: Kube Christopher M.
Published: March 2017

This article reevaluates two foundational models for bulk ultrasonic wave propagation in polycrystals. A decoupling of real and imaginary parts of the effective wave number permits a simple iterative method to obtain longitudinal and shear wave attenuation constants and phase velocity relations. The zeroth-order solution is that of Weaver [J. Mech. Phys. Solids 38, 55–86 (1990)]. Continued iteration converges to the unified theory solution of Stanke and Kino [J. Acoust. Soc. Am. 75, 665–681 (1984)]. The converged solution is valid for all frequencies. The iterative method mitigates the need to solve a nonlinear, complex-valued system of equations, which makes the models more robust and accessible to researchers. An analysis of the variation between the solutions is conducted and is shown to be proportional to the degree of inhomogeneity in the polycrystal.
Cancer immunotherapy comes of age
Authors: Dance Amber
Published: March 2017

Oncologists have long rested their treatment plans on three so-called "pillars"—chemotherapy, surgery, and radiation. But in recent years, scientists have been busily erecting a fourth pillar: immunotherapy. The idea of harnessing the immune system to fight cancer has already moved from the lab to the clinic, thanks to technologies such as checkpoint inhibitors and genetically engineered immune cells.

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Inflammation boosts bacteriophage transfer between
Salmonella
spp.
Authors: Diard Médéric , Bakkeren Erik , Cornuault Jeffrey K. , Moor Kathrin , Hausmann Annika , Sellin Mikael E. , Loverdo Claude , Aertsen Abram , Ackermann Martin , De Paepe Marianne , Slack Emma , Hardt Wolf-Dietrich
Published: March 2017

The parasite of my parasite is my friend?

Virulence factors of pathogenic bacteria can be swapped by means of bacterial viruses called phages. In turn, the pathogenic bacteria are under attack by the hosts' immune responses. Diard
et al.
discovered that SopEϕ, a phage parasite of pathogenic
Salmonella
species, is encouraged to spread between bacteria by the mouse host's inflammatory responses. Conversely, mucosal vaccination against
Salmonella
reduced inflammatory responses and curbed the transfer of SopEϕ to naïve bacteria.

Science
, this issue p.
1211
Reversion of antibiotic resistance in
Mycobacterium tuberculosis
by spiroisoxazoline SMARt-420
Authors: Blondiaux Nicolas , Moune Martin , Desroses Matthieu , Frita Rosangela , Flipo Marion , Mathys Vanessa , Soetaert Karine , Kiass Mehdi , Delorme Vincent , Djaout Kamel , Trebosc Vincent , Kemmer Christian , Wintjens René , Wohlkönig Alexandre , Antoine Rudy , Huot Ludovic , Hot David , Coscolla Mireia , Feldmann Julia , Gagneux Sebastien , Locht Camille , Brodin Priscille , Gitzinger Marc , Déprez Benoit , Willand Nicolas , Baulard Alain R.
Published: March 2017

Countering TB prodrug resistance

The arsenal of antibiotics for treating tuberculosis (TB) contains many prodrugs, such as ethionamide, which need activation by normal metabolism to release their toxic effects. Ethionamide is potentiated by small molecules. Blondiaux
et al.
screened for more potent analogs and identified a lead compound called SMARt-420. This small molecule inactivates a TetR-like repressor, EthR2, and boosts ethionamide activation. SMARt-420 successfully promoted clearance of multidrug-resistant strains of
Mycobacterium tuberculosis
from the lungs of mice.

Science
, this issue p.
1206
Building Archean cratons from Hadean mafic crust
Authors: O’Neil Jonathan , Carlson Richard W.
Published: March 2017

Archean cratons get a Hadean mash-up

The vast majority of the rock record over Earth's 4.6-billion-year history has been destroyed through subduction and recycling back into the mantle. Although some slivers of 4-billion-year-old crust remain in the rock record, only isolated zircon mineral grains are dated to be older. However, O'Neil and Carlson found isotopic evidence of reworked basaltic crust more than 4.3 billion years old mixed into some of the 2.7-billion-year-old rocks of the Superior Province in Canada. Thus, our planet's oldest crust was reworked and retained during formation of at least one continental craton.

Science
, this issue p.
1199
How economics can shape precision medicines
Authors: Stern A. D. , Alexander B. M. , Chandra A.
Published: March 2017

Innovation incentives, pricing, and access are critical
The cancer epigenome: Concepts, challenges, and therapeutic opportunities
Authors: Dawson Mark A.
Published: March 2017

Cancer biology is profoundly influenced by changes in the epigenome. Because the dynamic plasticity of the epigenome lends itself well to therapeutic manipulation, the past few years have witnessed an unprecedented investment in the development, characterization, and translation of targeted epigenetic therapies. In this review, I provide a broad context for recent developments that offer a greater understanding of how epigenetic regulators facilitate the initiation, maintenance, and evolution of cancer. I discuss newly developed epigenetic therapies and the cellular and molecular mechanisms that may govern sensitivity and resistance to these agents. I also review the rationale for future combination therapies involving existing and emerging epigenetic drugs.
PARP inhibitors: Synthetic lethality in the clinic
Authors: Lord Christopher J. , Ashworth Alan
Published: March 2017

PARP inhibitors (PARPi), a cancer therapy targeting poly(ADP-ribose) polymerase, are the first clinically approved drugs designed to exploit synthetic lethality, a genetic concept proposed nearly a century ago. Tumors arising in patients who carry germline mutations in either
BRCA1
or
BRCA2
are sensitive to PARPi because they have a specific type of DNA repair defect. PARPi also show promising activity in more common cancers that share this repair defect. However, as with other targeted therapies, resistance to PARPi arises in advanced disease. In addition, determining the optimal use of PARPi within drug combination approaches has been challenging. Nevertheless, the preclinical discovery of PARPi synthetic lethality and the route to clinical approval provide interesting lessons for the development of other therapies. Here, we discuss current knowledge of PARP inhibitors and potential ways to maximize their clinical effectiveness.
Learning from monkey “talk”
Authors: Snowdon Charles T.
Published: March 2017

Nonhuman primates are capable of several key elements of human language
Atoms on the move—finding the hydrogen
Authors: Cairney Julie
Published: March 2017

A cryogenic atom probe technique allows direct observation of hydrogen at the atomic scale
A Single-Dose Recombinant Parainfluenza Virus 5-Vectored Vaccine Expressing Respiratory Syncytial Virus (RSV) F or G Protein Protected Cotton Rats and African Green Monkeys from RSV Challenge
Authors: Wang Dai , Phan Shannon , DiStefano Daniel J. , Citron Michael P. , Callahan Cheryl L. , Indrawati Lani , Dubey Sheri A. , Heidecker Gwendolyn J. , Govindarajan Dhanasekaran , Liang Xiaoping , He Biao , Espeseth Amy S.
Published: March 2017

Human respiratory syncytial virus (RSV) is a common cause of severe respiratory disease among infants, immunocompromised individuals, and the elderly. No licensed vaccine is currently available. In this study, we evaluated two parainfluenza virus 5 (PIV5)-vectored vaccines expressing RSV F (PIV5/F) or G (PIV5/G) protein in the cotton rat and African green monkey models for their replication, immunogenicity, and efficacy of protection against RSV challenge. Following a single intranasal inoculation, both animal species shed the vaccine viruses for a limited time but without noticeable clinical symptoms. In cotton rats, the vaccines elicited RSV F- or G-specific serum antibodies and conferred complete lung protection against RSV challenge at doses as low as 10
3
PFU. Neither vaccine produced the enhanced lung pathology observed in animals immunized with formalin-inactivated RSV. In African green monkeys, vaccine-induced serum and mucosal antibody responses were readily detected, as well. PIV5/F provided nearly complete protection against RSV infection in the upper and lower respiratory tract at a dose of 10
6
PFU of vaccine. At the same dose levels, PIV5/G was less efficacious. Both PIV5/F and PIV5/G were also able to boost neutralization titers in RSV-preexposed African green monkeys. Overall, our data indicated that PIV5/F is a promising RSV vaccine candidate.

IMPORTANCE
A safe and efficacious respiratory syncytial virus (RSV) vaccine remains elusive. We tested the recombinant parainfluenza virus 5 (PIV5) vectors expressing RSV glycoproteins for their immunogenicity and protective efficacy in cotton rats and African green monkeys, which are among the best available animal models to study RSV infection. In both species, a single dose of intranasal immunization with PIV5-vectored vaccines was able to produce systemic and local immunity and to protect animals from RSV challenge. The vaccines could also boost RSV neutralization antibody titers in African green monkeys that had been infected previously. Our data suggest that PIV5-vectored vaccines could potentially protect both the pediatric and elderly populations and support continued development of the vector platform.
Prion Strain Characterization of a Novel Subtype of Creutzfeldt-Jakob Disease
Authors: Galeno Roberta , Di Bari Michele Angelo , Nonno Romolo , Cardone Franco , Sbriccoli Marco , Graziano Silvia , Ingrosso Loredana , Fiorini Michele , Valanzano Angelina , Pasini Giulia , Poleggi Anna , Vinci Ramona , Ladogana Anna , Puopolo Maria , Monaco Salvatore , Agrimi Umberto , Zanusso Gianluigi , Pocchiari Maurizio
Published: March 2017

In 2007, we reported a patient with an atypical form of Creutzfeldt-Jakob disease (CJD) heterozygous for methionine-valine (MV) at codon 129 who showed a novel pathological prion protein (PrPTSE) conformation with an atypical glycoform (AG) profile and intraneuronal PrP deposition. In the present study, we further characterize the conformational properties of this pathological prion protein (PrPTSEMVAG), showing that PrPTSEMVAGis composed of multiple conformers with biochemical properties distinct from those of PrPTSEtype 1 and type 2 of MV sporadic CJD (sCJD). Experimental transmission of CJD-MVAGto bank voles and gene-targeted transgenic mice carrying the human prion protein gene (TgHu mice) showed unique transmission rates, survival times, neuropathological changes, PrPTSEdeposition patterns, and PrPTSEglycotypes that are distinct from those of sCJD-MV1 and sCJD-MV2. These biochemical and experimental data suggest the presence of a novel prion strain in CJD-MVAG.

IMPORTANCESporadic Creutzfeldt-Jakob disease is caused by the misfolding of the cellular prion protein, which assumes two different major conformations (type 1 and type 2) and, together with the methionine/valine polymorphic codon 129 of the prion protein gene, contribute to the occurrence of distinct clinical-pathological phenotypes. Inoculation in laboratory rodents of brain tissues from the six possible combinations of pathological prion protein types with codon 129 genotypes results in the identification of 3 or 4 strains of prions. We report on the identification of a novel strain of Creutzfeldt-Jakob disease isolated from a patient who carried an abnormally glycosylated pathological prion protein. This novel strain has unique biochemical characteristics, does not transmit to humanized transgenic mice, and shows exclusive transmission properties in bank voles. The identification of a novel human prion strain improves our understanding of the pathogenesis of the disease and of possible mechanisms of prion transmission.
Incidence, risk factors and clinical outcomes of acute kidney injury associated with scrub typhus: a retrospective study of 510 consecutive patients in South Korea (2001–2013)
Authors: Hwang Kyungo , Jang Ha Nee , Lee Tae Won , Cho Hyun Seop , Bae Eunjin , Chang Se-Ho , Park Dong Jun
Published: March 2017

Objectives

Renal involvement in scrub typhus ranges from simple urinary abnormalities to acute kidney injury (AKI) leading to death. This study evaluated the incidence, predictors and prognosis of AKI associated with scrub typhus according to the RIFLE (risk, injury, failure, loss, end-stage kidney disease) criteria.

Methods

We retrospectively evaluated the medical records of patients diagnosed with scrub typhus from January 2001 to November 2013 in Gyeongsang National University Hospital.

Results

During the study period, 510 patients were diagnosed with scrub typhus and the incidence of AKI was 35.9%. There were 132 (25.9%) patients at risk, 37 (7.3%) with injury and 14 (2.7%) with failure. In comparison with the non-AKI group, the AKI group was older (73.9 vs 63.4 years, p<0.001) and had more comorbidities such as hypertension, diabetes mellitus and chronic kidney disease (CKD). AKI frequently occurs in hypertensive patients taking angiotensin receptor blockers or ACE inhibitors (p=0.002), and in patients with diabetes with higher glycated haemoglobin levels (p=0.033). Haematuria and proteinuria were more frequent in the AKI group. There was no relationship between the severity of proteinuria and occurrence of AKI. Intensive care unit admission and death were more frequent in the AKI group. The renal function of most patients with AKI recovered without sequelae, except for 1 patient who had underlying CKD. Multivariate analysis showed that age, presence of CKD, serum albumin level and time to hospital presentation after symptom onset were independent predictors of AKI in patients with scrub typhus.

Conclusions

Our current results suggest that the presence of underlying CKD, older age, lower serum albumin level and time to hospital presentation after symptom onset were important risk factors to determine occurrence of AKI. Whether earlier diagnosis and treatment in patients with the above risk factors reduce the incidence and severity of AKI deserves to be investigated.
Alcohol policy changes and 22-year trends in individual alcohol consumption in a Swiss adult population: a 1993–2014 cross-sectional population-based study
Authors: Dumont Shireen , Marques-Vidal Pedro , Favrod-Coune Thierry , Theler Jean-Marc , Gaspoz Jean-Michel , Broers Barbara , Guessous Idris
Published: March 2017

Objective

Evidence on the impact of legislative changes on individual alcohol consumption is limited. Using an observational study design, we assessed trends in individual alcohol consumption of a Swiss adult population following the public policy changes that took place between 1993 and 2014, while considering individual characteristics and secular trends.

Design

Cross-sectional study.

Setting

Swiss general adult population.

Participants

Data from 18 963 participants were collected between 1993 and 2014 (aged 18–75 years).

Outcome measures

We used data from the ‘Bus Santé’ study, an annual health survey conducted in random samples of the adult population in the State of Geneva, Switzerland. Individual alcohol intake was assessed using a validated food frequency questionnaire. Individual characteristics including education were self-reported. 7 policy changes (6 about alcohol and 1 about tobacco) that occurred between 1993 and 2014 defined 6 different periods. We predicted alcohol intake using quantile regression with multivariate analysis for each period adjusting for participants' characteristics and tested significance periods. Sensitivity analysis was performed including drinkers only, the 10th centile of highest drinkers and smoker's status.

Results

Between 1993 and 2014, participants' individual alcohol intake decreased from 7.1 to 5.4 g/day (24% reduction, p<0.001). Men decreased their alcohol intake by 34% compared with 22% for women (p<0.001). The decrease in alcohol intake remained significant when considering drinkers only (28% decrease, p<0.001) and the 10th centile highest drinkers (24% decrease, p<0.001). Consumption of all alcoholic beverages decreased between 1993 and 2014 except for the moderate consumption of beer, which increased. After adjustment for participants' characteristics and secular trends, no independent association between alcohol legislative changes and individual alcohol intake was found.

Conclusions

Between 1993 and 2014, alcohol consumption decreased in the Swiss adult population independently of policy changes.
Clinical usefulness of the free web-based image analysis application ImmunoRatio for assessment of Ki-67 labelling index in breast cancer
Authors: Yeo Min-Kyung , Kim Hee Eun , Kim Sung Hun , Chae Byung Joo , Song Byung Joo , Lee Ahwon
Published: March 2017

Aims

Ki-67 is a prognostic marker in breast cancer; however, the use of the Ki-67 labelling index (LI) in clinical practice requires a consistent and easily accessible scoring method. The present study evaluated the use of the free internet-based image analysis program ImmunoRatio to score Ki-67 LI in breast cancer in comparison with manual counting.

Methods

Ki-67 immunohistochemical detection was performed in 577 breast cancer cases, and the Ki-67 LI was determined by ImmunoRatio and manual counting.

Results

The Ki-67 LI determined by ImmunoRatio correlated well with that obtained by manual counting. The concordance rate between ImmunoRatio and manual counting was excellent (κ coefficient of 0.881) at a Ki-67 LI cut-off value of 20%. Cases with high Ki-67 LI by ImmunoRatio were associated with poor overall survival, in particular in the hormone receptor positive group.

Conclusions

The web-based automated image analysis program ImmunoRatio is an attractive alternative to manual counting to determine the Ki-67 LI in breast cancer.
Glutathione Peroxidase Activity and Expression Levels are Significantly Increased in Acute Coronary Syndromes
Authors: Holley Ana , Pitman Janet , Miller John , Harding Scott , Larsen Peter
Published: March 2017

High levels of the antioxidant enzyme, glutathione peroxidase (GPx), have been associated with improved outcomes following acute coronary syndromes (ACS), suggesting a protective role. How GPx levels are altered with coronary disease is not clearly established. This study examined GPx activity, protein, and mRNA levels in healthy controls, patients with stable coronary artery disease (CAD), and patients with ACS. We studied 20 individuals from each of the healthy control, stable CAD, and ACS groups. GPx activity and protein levels, along with oxidized low-density lipoprotein (oxLDL) were assayed in plasma. GPx mRNA levels from whole blood were quantified using real-time PCR. Levels of GPx activity in the plasma were higher in ACS (109±7.7 U/mL) compared with patients with stable CAD (95.2±16.4 U/mL, p<0.01) and healthy controls (87.6±8.3 U/mL, p<0.001). Plasma GPx protein levels were also elevated in ACS (21.6±9.5 µg/mL) compared with patients with stable CAD (16.5±2.8 µg/mL, p<0.05) and healthy controls (16.3±5.3 µg/mL, p<0.05). Levels of GPX1, GPX3, and GPX4 mRNA were significantly higher in the patients with ACS. Levels of oxLDL were also significantly higher in patients with ACS (61.9±22.2 U/L) than in patients with stable CAD (47.8±10.4 U/L, p<0.05) and healthy controls (48.9±11.9 U/L, p<0.05). Levels of oxLDL, GPx activity, protein, and mRNA are all significantly higher in patients with ACS compared with patients with stable CAD and healthy controls. These findings suggest that GPx may be upregulated in response to a change in oxidative stress during an ACS.
Prognosis of complete versus incomplete revascularisation of patients with STEMI with multivessel coronary artery disease: an observational study
Authors: Dimitriu-Leen Aukelien C , Hermans Maaike P J , Veltman Caroline E , van der Hoeven Bas L , van Rosendael Alexander R , van Zwet Erik W , Schalij Martin J , Delgado Victoria , Bax Jeroen J , Scholte Arthur J H A
Published: March 2017

Objective

The best strategy in patients with acute ST-segment elevation myocardial infarction (STEMI) with multivessel coronary artery disease (CAD) regarding completeness of revascularisation of the non-culprit lesion(s) is still unclear. To establish which strategy should be followed, survival rates over a longer period should be evaluated. The aim of this study was to investigate whether complete revascularisation, compared with incomplete revascularisation, is associated with reduced short-term and long-term all-cause mortality in patients with first STEMI and multivessel CAD.

Methods

This retrospective study consisted of 518 patients with first STEMI with multivessel CAD. Complete revascularisation (45%) was defined as the treatment of any significant coronary artery stenosis (≥70% luminal narrowing) during primary or staged percutaneous coronary intervention prior to discharge. The primary end point was all-cause mortality.

Results

Incomplete revascularisation was not independently associated with 30-day all-cause mortality in patients with acute first STEMI and multivessel CAD (OR 1.98; 95% CI 0.62to6.37; p=0.25). During a median long-term follow-up of 6.7 years, patients with STEMI with multivessel CAD and incomplete revascularisation showed higher mortality rates compared with patients who received complete revascularisation (24% vs 12%, p<0.001), and these differences remained after excluding the first 30 days. However, in multivariate analysis, incomplete revascularisation was not independently associated with increased all-cause mortality during long-term follow-up in the group of patients with STEMI who survived the first 30 days post-STEMI (HR 1.53 95% CI 0.89-2.61, p=0.12).

Conclusion

In patients with acute first STEMI and multivessel CAD, incomplete revascularisation compared with complete revascularisation was not independently associated with increased short-term and long-term all-cause mortality.
Atorvastatin can ameliorate left atrial stunning induced by radiofrequency ablation for atrial fibrillation
Authors: Xie Ruiqin , Yang Yingtao , Cui Wei , Yin Hongning , Zheng Hongmei , Zhang Jidong , You Ling
Published: March 2017

The objective of this study was to study the functional changes of the left atrium after radiofrequency ablation treatment for atrial fibrillation and the therapeutic effect of atorvastatin. Fifty-eight patients undergoing radiofrequency ablation for atrial fibrillation were randomly divided into non-atorvastatin group and atorvastatin group. Patients in the atorvastatin group were treated with atorvastatin 20 mg p.o. per night in addition to the conventional treatment of atrial fibrillation; patients in the non-atorvastatin group received conventional treatment of atrial fibrillation only. Echocardiography was performed before radiofrequency ablation operation and 1 week, 2 weeks, 3 weeks, and 4 weeks after operation. Two-dimensional ultrasound speckle tracking imaging system was used to measure the structural indexes of the left atrium. Results indicated that there was no significant change for indexes representing the structural status of the left atrium within a month after radiofrequency ablation (P > 0.05); however, there were significant changes for indexes representing the functional status of the left atrium. There were also significant changes in indexes reflecting left atrial strain status: the S and SRs of atorvastatin group were higher than those of non-atorvastatin group (P < 0.05). In summary, atorvastatin could improve left atrial function and shorten the duration of atrial stunning after radiofrequency ablation of atrial fibrillation.
Analogues of glacial valley profiles in particle mechanics and in cosmology
Authors: Faraoni Valerio , Cardini Adriana M.
Published: March 2017

An ordinary differential equation describing the transverse profiles of U-shaped glacial valleys has two formal analogies, which we explore in detail, bridging these different areas of research. First, an analogy with point particle mechanics completes the description of the solutions. Second, an analogy with the Friedmann equation of relativistic cosmology shows that the analogue of a glacial valley profile is a universe with a future singularity of interest in theoretical models of cosmology. A Big Freeze singularity, which was not previously observed for positive curvature index, is also contained in the dynamics.
Sensing characteristics of pure-shear film bulk acoustic resonator in viscous liquids
Authors: Chen Da , Song Shuren , Zhang Dexue , Wang Peng , Liu Weihui
Published: March 2017

We presented a pure-shear film bulk acoustic resonator (FBAR) and investigated its sensing characteristics in viscous liquids. In the resonator, the electrodes were located on the surface of c-axis-oriented AlN film to generate the lateral electric field and excite the shear acoustic resonance. Compared with the typical quasi-shear film bulk acoustic resonator based on inclined c-axis-oriented AlN or ZnO piezoelectric film, the proposed device exhibits significantly higher Q-factors and a notably improved detection limit, particularly in water and viscous liquids. The frequency shifts show a linear dependency on the square root of the product of the liquid viscosity and density of the glycerol solution in the viscosity range of 1–5 mPa[Formula: see text]s. Furthermore, we measured the mass sensitivity through real-time monitoring of the frequency change during the volatilization process of the loaded saline solutions. The proposed device shows the mass sensitivity of 465 Hz[Formula: see text]cm2/ng and the mass resolutions of 0.17 ng/cm2 in air, 0.25 ng/cm2 in water and 2.08 ng/cm2 in 50% glycerol solution, respectively. The obtained results clearly indicate that the proposed device is capable of using in liquid phase detection with high sensitivity requirements.
Efficient and Fast Iris Localization Using Binary Radial Gradient Features for Human–Computer Interaction
Authors: Kim Hong-In , Kim Jin-Bum , Park Rae-Hong
Published: March 2017

This paper proposes an efficient and fast iris localization method. It uses support vector machine learning of iris features that represent closed outer and inner iris boundaries encompassing a low-intensity region. In addition, depending on the location of the iris in an eye image, an iris detection method is proposed based on three sub-datasets of eye images (middle, right, and left sub-datasets) with different iris features. The proposed method is implemented using fast sliding window and fast computation of the iris detection score with binary features. Compared with state-of-the-art methods, experimental results show that the proposed method is twice as fast and has comparable accuracy, even when factoring in head rotation, glasses, and highlights.
Constant and Random Full Backup Models with Incremental and Differential Backup Schemes
Authors: Nakamura Syouji , Zhao Xufeng , Nakagawa Toshio
Published: March 2017

It has been commonly known in a Database Management System that constant plans of incremental/differential backup schemes are set up and their full backups should be done to balance the costs of data backup and failure recovery. In this paper, we consider a database system that is running for 24/7 and has several random busy states of updates, and we suppose that incremental/differential backups are implemented after each update and full backups are triggered at constant time [Formula: see text] and random updates [Formula: see text]. That is, models with decision variables of [Formula: see text] and [Formula: see text] for full backups with random incremental/differential backups are considered. We obtain the expected costs of data backup and failure recovery and the expected cost rates for full backups. Optimum solutions to minimize the expected cost rates are discussed in analytical ways. Furthermore, full backups that are made at time [Formula: see text] and updates [Formula: see text] are considered as constant and random modes respectively and compared analytically. For the discussions, numerical examples in exponential cases are given.
STRUCTURAL, ELECTRICAL AND OPTICAL PROPERTIES OF TiO2THIN FILM DEPOSITED ON THE NANO POROUS SILICON TEMPLATE
Authors: BAHAR MAHMOOD , DERMANI ENSIEH KHALILI
Published: March 2017

The porous silicon (PSi), which is produced by the electrochemical etching, has been used as a substrate for the growth of the titanium oxide (TiO2) thin films. By using the EBPVD method, TiO2thin films have been deposited on the surface of the PSi substrate. TiO2/PSi layers were annealed at the temperature of 400[Formula: see text]C, 500[Formula: see text]C and 600[Formula: see text]C for different tests. The morphology and structures of layers were investigated by the scanning electron microscopy (SEM) and X-ray diffraction (XRD). The current–voltage characteristic curves of samples and the ideality factor of heterojunction were studied. The results showed that the electrical properties of the samples change with increase in the annealing temperature. The optical properties of the prepared samples were investigated by using UV–Vis and photoluminescence (PL) spectroscopy. Green light emission of the PSi combined with the blue light and violet–blue emission obtained from the TiO2/PSi PL spectra. The results showed that the optical band gap energy of the PSi has increased from 1.86[Formula: see text]eV to 2.93[Formula: see text]eV due to the deposition of TiO2thin film.
Resonance of a Quasi-Zero Stiffness Vibration System Under Base Excitation with Load Mismatch
Authors: Cheng Chun , Li Shunming , Wang Yong , Jiang Xingxing
Published: March 2017

The primary resonance and 1/3 subharmonic resonance of a quasi-zero stiffness (QZS) vibration system under base excitation with load mismatch are studied in this research. The incremental harmonic balance (IHB) method is applied to obtain highly accurate solutions involving more dynamic behaviors. The effect of the offset displacement mainly caused by overloading on the primary resonance and displacement transmissibility is investigated. The results indicate that the system exhibits a softening characteristic under certain conditions. Although the isolation performance of the QZS system deteriorates, it still outperforms the equivalent linear system for excitation amplitudes that are not too large. The parametric analysis of the 1/3 subharmonic resonance shows that the response is unbounded, and interesting dynamic behaviors can be observed, such as the jump phenomenon. Moreover, the 1/3 subharmonic resonance can be avoided by applying a larger damping or reducing the excitation amplitude to a lower level.
NEAT-FLEX: Predicting the conformational flexibility of amino acids using neuroevolution of augmenting topologies
Authors: Grisci Bruno , Dorn Márcio
Published: March 2017

The development of computational methods to accurately model three-dimensional protein structures from sequences of amino acid residues is becoming increasingly important to the structural biology field. This paper addresses the challenge of predicting the tertiary structure of a given amino acid sequence, which has been reported to belong to the NP-Complete class of problems. We present a new method, namely NEAT–FLEX, based on NeuroEvolution of Augmenting Topologies (NEAT) to extract structural features from (ABS) proteins that are determined experimentally. The proposed method manipulates structural information from the Protein Data Bank (PDB) and predicts the conformational flexibility (FLEX) of residues of a target amino acid sequence. This information may be used in three-dimensional structure prediction approaches as a way to reduce the conformational search space. The proposed method was tested with 24 different amino acid sequences. Evolving neural networks were compared against a traditional error back-propagation algorithm; results show that the proposed method is a powerful way to extract and represent structural information from protein molecules that are determined experimentally.
Circular orbits in the Taub–NUT and massless Taub–NUT spacetime
Authors: Pradhan Parthapratim
Published: March 2017

In this work, we study the equatorial causal geodesics of the Taub–NUT (TN) spacetime in comparison with massless TN spacetime. We emphasized both on the null circular geodesics and time-like circular geodesics. From the effective potential diagram of null and time-like geodesics, we differentiate the geodesics structure between TN spacetime and massless TN spacetime. It has been shown that there is a key role of the NUT parameter to changes the shape of pattern of the potential well in the NUT spacetime in comparison with massless NUT spacetime. We compared the innermost stable circular orbit (ISCO), marginally bound circular orbit (MBCO) and circular photon orbit (CPO) of the said spacetime with graphically in comparison with massless cases. Moreover, we compute the radius of ISCO, MBCO and CPO for extreme TN black hole (BH). Interestingly, we show that these three radii coincides with the Killing horizon, i.e. the null geodesic generators of the horizon. Finally in Appendix A, we compute the center-of-mass (CM) energy for TN BH and massless TN BH. We show that in both cases, the CM energy is finite. For extreme NUT BH, we found that the diverging nature of CM energy. First, we have observed that a non-asymptotic flat, spherically symmetric and stationary extreme BH showing such feature.
Spin angular momentum of proton spin puzzle in complex octonion spaces
Authors: Weng Zi-Hua
Published: March 2017

The paper focuses on considering some special precessional motions as the spin motions, separating the octonion angular momentum of a proton into six components, elucidating the proton angular momentum in the proton spin puzzle, especially the proton spin, decomposition, quarks and gluons, and polarization and so forth. Maxwell was the first to use the quaternions to study the electromagnetic fields. Subsequently the complex octonions are utilized to depict the electromagnetic field, gravitational field, and quantum mechanics and so forth. In the complex octonion space, the precessional equilibrium equation infers the angular velocity of precession. The external electromagnetic strength may induce a new precessional motion, generating a new term of angular momentum, even if the orbital angular momentum is zero. This new term of angular momentum can be regarded as the spin angular momentum, and its angular velocity of precession is different from the angular velocity of revolution. The study reveals that the angular momentum of the proton must be separated into more components than ever before. In the proton spin puzzle, the orbital angular momentum and magnetic dipole moment are independent of each other, and they should be measured and calculated respectively.
Some characterizations on minimal lightlike submanifolds
Authors: Kumar Sangeet
Published: March 2017

The present paper deals with the study of minimal lightlike submanifolds. We investigate a class of lightlike submanifolds namely, generic lightlike submanifolds under the minimal condition. We give one nontrivial example for minimal generic lightlike submanifolds and derive some characterization theorems for a generic lightlike submanifold to be a minimal lightlike submanifold. We also establish some conditions for the distributions for generic lightlike submanifolds to be minimal. We further derive the expressions for sectional curvature, null sectional curvature and induced Ricci tensor for a minimal lightlike submanifold. Finally, we prove that for a minimal lightlike submanifold, the null sectional curvature vanishes and the induced Ricci tensor is symmetric.
Charged three-dimensions black holes in Weitzenböck geometry
Authors: Nashed G. G. L.
Published: March 2017

In this study, we propose to derive circularly symmetric black holes in three-dimensions Maxwell-teleparallel gravity using a non-diagonal traid. Singularities and horizons of these black holes are analyzed. The conserved quantities are calculated using Komar formula and vanishing values are obtained. Therefore, a regularization through relecolization method is applied and finite values of mass and angular momentum are obtained.
A study of three-dimensional paracontact (κ̃,μ̃,ν̃)-spaces
Authors: Küpeli Erken İrem , Murathan Cengizhan
Published: March 2017

This paper is a study of three-dimensional paracontact metric [Formula: see text]-manifolds. Three-dimensional paracontact metric manifolds whose Reeb vector field [Formula: see text] is harmonic are characterized. We focus on some curvature properties by considering the class of paracontact metric [Formula: see text]-manifolds under a condition which is given at Definition 3.1. We study properties of such manifolds according to the cases [Formula: see text] [Formula: see text] and construct new examples of such manifolds for each case. We also show the existence of paracontact metric [Formula: see text] spaces with dimension greater than 3, such that [Formula: see text] but [Formula: see text]
On f(R) gravity in scalar–tensor theories
Authors: Ntahompagaze Joseph , Abebe Amare , Mbonye Manasse
Published: March 2017

We study [Formula: see text] gravity models in the language of scalar–tensor (ST) theories. The correspondence between [Formula: see text] gravity and ST theories is revisited since [Formula: see text] gravity is a subclass of Brans–Dicke models, with a vanishing coupling constant ([Formula: see text]). In this treatment, four [Formula: see text] toy models are used to analyze the early-universe cosmology, when the scalar field [Formula: see text] dominates over standard matter. We have obtained solutions to the Klein–Gordon equation for those models. It is found that for the first model [Formula: see text], as time increases the scalar field decreases and decays asymptotically. For the second model [Formula: see text], it was found that the function [Formula: see text] crosses the [Formula: see text]-axis at different values for different values of [Formula: see text]. For the third model [Formula: see text], when the value of [Formula: see text] is small, the potential [Formula: see text] behaves like the standard inflationary potential. For the fourth model [Formula: see text], we show that there is a transition between [Formula: see text]. The behavior of the potentials with [Formula: see text] is totally different from those with [Formula: see text]. The slow-roll approximation is applied to each of the four [Formula: see text] models and we obtain the respective expressions for the spectral index [Formula: see text] and the tensor-to-scalar ratio [Formula: see text].
Metal–Organic Framework for Selective Gas Scavenging
Authors: He Jiating , Li Xu
Published: March 2017

Selective gas adsorption plays an important role in adsorptive separation of gases and scavenging unfavorable or hazardous gases. The use of cost-effective and environmentally friendly materials for selective gas adsorption has become one of the most pressing needs today. The development of new adsorbents is essential but difficult due to the selectivity and efficiency requirements for practical application. As potential scavengers, metal–organic frameworks (MOFs) have drawn great attention. In this review, the current progress of science and technology development of MOFs on selective gas scavenging will be highlighted. Future perspectives for exploring MOFs for practical application will also be put forward.
Deep Learning in Medical Image Analysis
Authors: Shen Dinggang , Wu Guorong , Suk Heung-Il
Published: March 2017

This review covers computer-assisted analysis of images in the field of medical imaging. Recent advances in machine learning, especially with regard to deep learning, are helping to identify, classify, and quantify patterns in medical images. At the core of these advances is the ability to exploit hierarchical feature representations learned solely from data, instead of features designed by hand according to domain-specific knowledge. Deep learning is rapidly becoming the state of the art, leading to enhanced performance in various medical applications. We introduce the fundamentals of deep learning methods and review their successes in image registration, detection of anatomical and cellular structures, tissue segmentation, computer-aided disease diagnosis and prognosis, and so on. We conclude by discussing research issues and suggesting future directions for further improvement.
Progress in Human andTetrahymenaTelomerase Structure Determination
Authors: Chan Henry , Wang Yaqiang , Feigon Juli
Published: March 2017

Telomerase is an RNA–protein complex that extends the 3′ ends of linear chromosomes, using a unique telomerase reverse transcriptase (TERT) and template in the telomerase RNA (TR), thereby helping to maintain genome integrity. TR assembles with TERT and species-specific proteins, and telomerase function in vivo requires interaction with telomere-associated proteins. Over the past two decades, structures of domains of TR and TERT as well as other telomerase- and telomere-interacting proteins have provided insights into telomerase function. A recently reported 9-Å cryo–electron microscopy map of the Tetrahymena telomerase holoenzyme has provided a framework for understanding how TR, TERT, and other proteins from ciliate as well as vertebrate telomerase fit and function together as well as unexpected insight into telomerase interaction at telomeres. Here we review progress in understanding the structural basis of human and Tetrahymena telomerase activity, assembly, and interactions.
Geometric Principles for Designing Highly Symmetric Self-Assembling Protein Nanomaterials
Authors: Yeates Todd O.
Published: March 2017

Emerging protein design strategies are enabling the creation of diverse, self-assembling supramolecular structures with precision on the atomic scale. The design possibilities include various types of architectures: finite cages or shells, essentially unbounded two-dimensional and three-dimensional arrays (i.e., crystals), and linear or tubular filaments. In nature, structures of those types are generally symmetric, and, accordingly, symmetry provides a powerful guide for developing new design approaches. Recent design studies have produced numerous protein assemblies in close agreement with geometric specifications. For certain design approaches, a complete list of allowable symmetry combinations that can be used for construction has been articulated, opening a path to a rich diversity of geometrically defined protein materials. Future challenges include improving and elaborating on current strategies and endowing designed protein nanomaterials with properties useful in nanomedicine and material science applications.
Progress in Brewing Science and Beer Production
Authors: Bamforth C.W.
Published: March 2017

The brewing of beer is an ancient biotechnology, the unit processes of which have not changed in hundreds of years. Equally, scientific study within the brewing industry not only has ensured that modern beer making is highly controlled, leading to highly consistent, high-quality, healthful beverages, but also has informed many other fermentation-based industries.