bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECTS OF DIETARY NITRATE SUPPLEMENTATION ON 5 KM RUNNING TIME TRIAL PERFORMANCE IN TRAINED FEMALE RUNNERS
Authors: Lanceley R , Ranchordas M , Ruddock A
Published: October 2013

Ingestion of dietary nitrate supplementation enhances athletic time trial performance but data on its effectiveness in trained female runners is limited. The purpose of this study was to investigate the effect of beetroot juice supplementation (BRJ) on 5 km running time trial performance compared to a placebo (PLA) and no supplementation (CON). Using a double-blind, repeated-measures crossover design with a 14 day washout period, 11 trained female runners (age 20±3 years,52.6±4.6 mL.kg.min−1, body mass 53.0±3.9 kg, stature 164.2±5.8 cm) ingested 2×70 mL of either BRJ (∼8 mmoL·d−1nitrate) or PLA for 4 days and 2.5 h before performing a 5 km time trial. Blood pressure (BP), mean heart rate (HR), post-test blood lactate (BLa), 5 km time trial and 1 km split times were assessed. No main effect was found for change in systolic BP (CON=122±8, PLA=120±7, BRJ=114±9 mm Hg), but trends towards reductions after BRJ were observed, BRJ vs CON -8 mm Hg (-10 to 5; 90% CI, ES=0.82) and BRJ vs PLA 6 mm Hg (9 to  2; 90% CI, ES=0.64). No main effect was found for 5 km time trial performance (CON=1287±126, PLA=1268±109, BRJ=1237±109 s) but trends towards reductions after BRJ were observed, BRJ vs CON −49 s (73 to −26; 90% CI, ES=0.44) and BRJ and PLA −31 s (−48 to −14; 90% CI, ES=0.30). 1 km split times were similar between conditions except for the 2ndkm where BRJ was faster than CON by 16 s (−25 to −7; 90% CI and ES=0.61) and PLA by 12 s (20 to 4; 90% CI and ES=0.57). No between group differences were observed for mean HR (CON=182±8, PLA 181±7, BRJ=182±7 bpm−1; or post time trial BLa (CON=6.8±1.9, PLA=6.9±1.9, BRJ=6.9±1.9 mmol.L−1). Although not statistically significant, these results suggest BRJ supplementation improved 5 km time trial performance over PLA by 31 s (2.4%). Athletes should consider ingesting BRJ to improve 5 km running performance.
ABEL-SPORT™ TEST FOR ASSESSING OVER TRAINING SYNDROME AND DETECTING INFECTION
Authors: Knight J , Wakeman M , Reeves J
Published: October 2013

There are many tests available to the sports science team to manage training loads and measure the effects of physical, psychological, environmental and physiological interventions. However, those that aim to predict an infection and/or identify overtraining, generally remain wanting. And to complicate matters further there is often a lack of consensus as to what constitutes overreaching (OR) overtraining (OT) and the overtraining syndrome (OTS). We describe a reproducible test, on a small drop of blood, that can be performed close to the athlete on a portable luminometer (ABEL meter-1) or in a laboratory. The test does not measure a single biomarker of OTS but instead utilises hidden information acquired by circulating leucocytes as they patrol the body spotting pathogens, responding to markers of inflammation (cytokines and chemokines) and other changes in the blood that occur after strenuous exercise. These cells also know you have an infection before there are any signs or symptoms. The ABEL-sport™ test is designed to elicit this hidden information from the cells. The test incorporates the bioluminescent protein Pholasinâwhich emits light with reactive oxygen species (ROS). In the test, the NADPH oxidase system of the leucocytes is artificially activated to produce ROS. Light response graphs quantify changes in the rate of production and magnitude of the ROS generated. The interpretation of the graphs is used to identify various responses during training, indicating if the athlete is heading towards OTS and identifying infections, superimposed on training curves. ABEL-sport™ provides objective assessments of an athlete which can support management decisions. The test has been validated for many years with elite and amateur athletes in many different fields and was successfully used by Skandia Team GB for two years prior to and in the final run up to the Olympics in Beijing in 2008 when Britain's squad topped the medal table in the Olympic sailing competition.
Shortness of Breath with Daily Activities questionnaire: validation and responder thresholds in patients with chronic obstructive pulmonary disease
Authors: Watkins Michael L , Wilcox Teresa K , Tabberer Maggie , Brooks Jean M , Donohue James F , Anzueto Antonio , Chen Wen-Hung , Crim Courtney
Published: October 2013

Objectives

To test the reliability, validity and responsiveness of the 13-item Shortness of Breath with Daily Activities (SOBDA) questionnaire, and determine the threshold for response and minimal important difference (MID).

Design

6 week, randomised, double-blind, placebo-controlled study.

Setting

40 centres in the USA between 29 October 2009 and 1 July 2010.

Primary and secondary outcome measures

547 patients with chronic obstructive pulmonary disease (COPD) were enrolled and 418 entered the 2-week run-in period. Data from the run-in period were collected to test internal consistency, test–retest reliability, convergent validity and known-groups validity of the SOBDA. Three hundred and sixty six patients were randomised 2:2:1 to fluticasone propionate/salmeterol 250/50 µg, salmeterol 50 µg or placebo, twice daily. Results from the SOBDA questionnaire, Patient Global Assessment of Change Question, modified Medical Research Council Dyspnoea Scale (mMRC), Clinician Global Impression of Dysponea Severity (CGI-S), Clinician Global Impression of Change Question and Chronic Respiratory Disease Questionnaire self-administered standardised version (CRQ-SAS) were evaluated; spirometry and safety parameters were measured. Study endpoints were selected to investigate the cross-sectional and longitudinal validity of the SOBDA questionnaire in relation to the clinical criteria.

Results

Internal consistency of the SOBDA questionnaire (Cronbach α) was 0.89. Test–retest reliability (intraclass correlation) was 0.94. The SOBDA weekly scores correlated with the patient-reported and clinician-reported mMRC, CGI-S and CRQ-SAS dyspnoea domain scores (0.29, 0.24, 0.24 and –0.68, respectively). The SOBDA weekly scores differentiated between the responders and the non-responders as rated by the patients and the clinicians. Anchor-based and supportive distribution-based analyses produced a range of the potential values for the threshold for the responders and MID.

Conclusions

The 13-item SOBDA questionnaire is reliable, valid and responsive to change in patients with COPD. On using anchor-based methods, the proposed responder threshold shows a −0.1 to −0.2 score change. A specific threshold value will be identified as more data are generated from future clinical trials.

Trial registration

NCT00984659; GlaxoSmithKline study number: ASQ112989.
Women's experiences in relation to stillbirth and risk factors for long-term post-traumatic stress symptoms: a retrospective study
Authors: Gravensteen Ida Kathrine , Helgadóttir Linda Björk , Jacobsen Eva-Marie , Rådestad Ingela , Sandset Per Morten , Ekeberg Øivind
Published: October 2013

Objectives

(1) To investigate the experiences of women with a previous stillbirth and their appraisal of the care they received at the hospital. (2) To assess the long-term level of post-traumatic stress symptoms (PTSS) in this group and identify risk factors for this outcome.

Design

A retrospective study.

Setting

Two university hospitals.

Participants

The study population comprised 379 women with a verified diagnosis of stillbirth (≥23 gestational weeks or birth weight ≥500 g) in a singleton or twin pregnancy 5–18 years previously. 101 women completed a comprehensive questionnaire in two parts.

Primary and secondary outcome measures

The women's experiences and appraisal of the care provided by healthcare professionals before, during and after stillbirth. PTSS at follow-up was assessed using the Impact of Event Scale (IES).

Results

The great majority saw (98%) and held (82%) their baby. Most women felt that healthcare professionals were supportive during the delivery (85.6%) and showed respect towards their baby (94.9%). The majority (91.1%) had received some form of short-term follow-up. One-third showed clinically significant long-term PTSS (IES ≥ 20). Independent risk factors were younger age (OR 6.60, 95% CI 1.99 to 21.83), induced abortion prior to stillbirth (OR 5.78, 95% CI 1.56 to 21.38) and higher parity (OR 3.46, 95% CI 1.19 to 10.07) at the time of stillbirth. Having held the baby (OR 0.17, 95% CI 0.05 to 0.56) was associated with less PTSS.

Conclusions

The great majority saw and held their baby and were satisfied with the support from healthcare professionals. One in three women presented with a clinically significant level of PTSS 5–18 years after stillbirth. Having held the baby was protective, whereas prior induced abortion was a risk factor for a high level of PTSS.

Trial registration

The study was registered athttp://www.clinicaltrials.gov, with registration number NCT 00856076.
The impact of an intervention programme employing a hands-on technique to reduce the incidence of anal sphincter tears: interrupted time-series reanalysis
Authors: Fretheim Atle , Odgaard-Jensen Jan , Røttingen John-Arne , Reinar Liv Merete , Vangen Siri , Tanbo Tom
Published: October 2013

Objective

To re-evaluate previously published findings from an uncontrolled before–after evaluation of an intervention programme to reduce the incidence of anal sphincter tears. A key component of the programme was the use of a hands-on technique where the birth attendant presses the neonate's head during the final stage of delivery while simultaneously supporting the woman's perineum with the other hand.

Design

Interrupted time-series analysis using segmented regression modelling.

Setting

Obstetric departments of five Norwegian hospitals.

Participants

All women giving births vaginally in the study hospitals, 2002–2008.

Methods

The main data source was the Medical Birth Registry of Norway. We estimated the change in incidence of anal sphincter tears before and after implementation of the intervention in the five intervention hospitals, taking into account the trends in incidence before and after implementation.

Main outcome measures

Incidence of anal sphincter tears and episiotomies.

Results

There were 75 543 registered births at the five included hospitals. We found a 2% absolute reduction in incidence of anal sphincter tears associated with the hospital intervention programme, representing almost a halving in the number of women experiencing serious anal sphincter tears. This is a substantially smaller estimate than previously reported. However, it does represent a highly significant decrease in anal sphincter injuries. The programme was also associated with a significant increase in episiotomies.

Conclusions

The intervention programme was associated with a significant reduction in the incidence of obstetric anal sphincter tears. Still, the findings should be interpreted with caution as they seem to contradict the findings from randomised controlled studies of similar interventions.
Use of autologous fat grafting for reconstruction postmastectomy and breast conserving surgery: a systematic review protocol
Authors: Agha Riaz A , Goodacre Tim , Orgill Dennis P
Published: October 2013

Introduction

There is growing interest in the potential use of autologous fat grafting (AFG) for the purposes of breast reconstruction. However, concerns have been raised regarding the technique's clinical effectiveness, safety and interference with screening mammography. The objective of this systematic review was to determine the oncological, clinical, aesthetic and functional, patient reported, process and radiological outcomes for AFG.

Methods and analysis

All original studies, including randomised controlled trials, cohorts studies, case–control studies, case series and case reports involving women undergoing breast reconstruction. All AFG techniques performed for the purposes of reconstruction in the postmastectomy or breast conserving surgery setting will be considered. Outcomes are defined within this protocol along; oncological, clinical, aesthetic and functional, patient reported, process and radiological domains. The search strategy has been devised to find papers about ‘fat grafting and breast reconstruction’ and is outlined within the body of this protocol. The full search strategy is outlined within the body of the protocol. The following electronic databases will be searched from 1 January 1986 to 6 June 2013: PubMed, MEDLINE, EMBASE, SCOPUS, CINAHL, PsycINFO, SciELO, The Cochrane Library, including the Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effect (DARE), the Cochrane Methodology Register, Health Technology Assessment Database, the NHS Economic Evaluation Databases and Cochrane Groups, ClinicalTrials.gov, Current Controlled Trials Database, the World Health Organisation (WHO) International Clinical Trials Registry Platform, UpToDate.com, NHS Evidence and the York Centre for Reviews and Dissemination. Grey literature searches will also be conducted as detailed in our review protocol. Eligibility assessment occurred in two stages, title and abstract screening and then full text assessment. Data were extracted and stored in a database with standardised extraction fields to facilitate easy and consistent data entry.

Ethics and dissemination

This systematic review will be published in a peer-reviewed journal. It will also be presented at national and international conferences in the fields of plastic, reconstructive and aesthetic surgery and at more general surgical and methodological conferences. It will be disseminated electronically and in print. Brief reports of the review findings will be disseminated directly to the appropriate audiences of surgeons and societies through email and other modes of communication. Updates of the review will be conducted to inform and guide healthcare practice and policy.

Protocol Registration

PROSPERO—National Institute of Health Research (NIHR) Prospective Register of Systematic Reviews (CRD42013005254)
Publishing priorities of biomedical research funders
Authors: Collins Ellen
Published: October 2013

Objectives

To understand the publishing priorities, especially in relation to open access, of 10 UK biomedical research funders.

Design

Semistructured interviews.

Setting

10 UK biomedical research funders.

Participants

12 employees with responsibility for research management at 10 UK biomedical research funders; a purposive sample to represent a range of backgrounds and organisation types.

Conclusions

Publicly funded and large biomedical research funders are committed to open access publishing and are pleased with recent developments which have stimulated growth in this area. Smaller charitable funders are supportive of the aims of open access, but are concerned about the practical implications for their budgets and their funded researchers. Across the board, biomedical research funders are turning their attention to other priorities for sharing research outputs, including data, protocols and negative results. Further work is required to understand how smaller funders, including charitable funders, can support open access.
Near-infrared spectroscopy in the assessment of suspected sepsis in the emergency department
Authors: Macdonald Stephen P J , Brown Simon G A
Published: October 2013

Background and aims

The conventional approach to sepsis resuscitation involves early interventions targeting global oxygenation and macro-haemodynamic variables such as central venous and systemic arterial pressures. There is increasing recognition of the importance of microcirculatory changes in shock states, including sepsis, and the relationship of these to outcome. Near-infrared spectroscopy (NIRS) is a recently developed non-invasive technology that measures tissue oxygen saturations (StO2), which may be an indirect measure of the adequacy of the microcirculation. StO2measurements, therefore, have the potential to identify patients who are at risk of progressing to organ dysfunction and could be used to guide resuscitation. This article reviews the current state of knowledge of NIRS in the setting of sepsis, examining its application, validity and prognostic value.

Methods

A search of the relevant literature was performed using Medline, Embase and Cochrane databases, and a qualitative analysis was undertaken.

Results

A limited number of observational studies, mostly conducted among patients with severe sepsis, have shown that NIRS may correlate with severity of illness but demonstrate a variable relationship between StO2and outcome.

Conclusions

Outstanding questions still remain as to whether NIRS can help to risk-stratify patients with suspected sepsis in the emergency department and the utility of StO2as a resuscitation target.
Has health in Spain been declining since the economic crisis?
Authors: Regidor Enrique , Barrio Gregorio , Bravo María J , de la Fuente Luis
Published: October 2013

Background

The economic recession starting in 2008 may be having negative effects on health.

Purpose

We aimed to identify and characterise changes in trends in 15 health indicators in Spain during the recession.

Methods

Joinpoint regression and average annual percent change (AAPC) were used to compare trends.

Results

Premature mortality rates from several causes of death, except from cancer, showed statistically significant downward trends during the recession, as did poor self-reported health. HIV incidence was stable. No indicator declined significantly more slowly during the recession than in the preceding 4-year period, and two declined significantly faster.

Conclusion

Health in Spain has continued to improve during the first four years of the economic recession at a rate equal to or higher than in previous years.
Modified balloon assisted coil embolization for the treatment of intracranial and cervical arterial aneurysms using coaxial dual lumen balloon microcatheters: initial experience
Authors: Jagadeesan Bharathi D , Siddiq Farhan , Grande Andrew W , Tummala Ramachandra P
Published: October 2013

Introduction

Traditional balloon assisted coil embolization techniques for intracranial aneurysms require a single lumen balloon to remodel the aneurysm neck and a separate microcatheter to place coils. Here we report utilization of a single coaxial dual balloon microcatheter to achieve both coil placement and neck remodeling in a series of intracranial and cervical arterial aneurysms.

Materials and methods

A series of five patients, including two with subarachnoid hemorrhage, presented to our institution with wide necked oblong aneurysms (8–30 mm maximum diameter). Coil embolization in four of these aneurysms was performed by advancing the tip of either a 4×10 mm Scepter C or a 4×11 mm Scepter XC balloon microcatheter (Microvention, Tustin, USA) into the aneurysm, inflating the balloon at the aneurysm neck, and placing the coils through the same microcatheter. In the fifth patient, who had a giant aneurysm at the top of the basilar artery, two Scepter XC balloon microcatheters were placed side by side and inflated simultaneously at the neck of the aneurysm; coil embolization was then successfully performed through both Scepter XC microcatheters.

Results

Coil embolization was successfully performed with this technique in all five aneurysms. There was no instance of aneurysm rupture, thromboembolic complications, occlusion of branch vessels near the aneurysm neck, or prolapse of coil loops into the parent vessel.

Conclusions

Aneurysmal neck remodeling and coil embolization can both be achieved using a single coaxial dual lumen balloon microcatheter in selected oblong intracranial and cervical arterial aneurysms.
Across-sectional survey of prevalence and correlates of couple sexual concurrency among married couples in fishing communities along Lake Victoria in Kisumu, Kenya
Authors: Kwena Zachary A , Mwanzo Isaac J , Bukusi Elizabeth A , Achiro Lilian F , Shisanya Chris A
Published: October 2013

Objective

Sexual concurrency has been associated with HIV infection. Since HIV in sub-Saharan Africa is mostly spread within the context of heterosexual couples, it is necessary that intervention is focused on such couples. We sought to establish the correlates of couple sexual concurrency in Kisumu, Kenya.

Methods

We conducted 1090 gender-matched interviews in 545 couples in a cross-sectional survey. A random sample of fishermen and their spouses from 33 fish-landing beaches along the shores of Lake Victoria in Kisumu were asked to enrol in the study. Couples were separated into different private rooms for simultaneous interviews that documented socioeconomic and behavioural characteristics, and information on number of sexual partnerships in the preceding 6 months and their status. Based on reported concurrency status of the spouses, a couple was categorised as either concurrent when at least one spouse reported a concurrent sexual relationship or non-concurrent.

Results

Overall, 32.1% of the men and 6.2% of the women had concurrent sexual relationships in the 6 months preceding the study, resulting in 37.6% of the couples being sexually concurrent. Unmet sexual desire, intra-spousal suspicions of infidelity, male dominance scripts, domestic violence, couples’ children and women's age were the correlates of couple sexual concurrency.

Conclusions

Unmet sexual desires, inter-spousal infidelity suspicions, male dominance scripts and domestic violence were the main correlates of couple sexual concurrency in these fishing communities.
Multiplex polymerase chain reaction using ethidium monoazide and propidium monoazide for distinguishing viable and dead cells of arcobacters in biofilm
Authors: Hrušková Lucie , Mot’ková Petra , Vytřasová Jarmila
Published: October 2013

This paper concerns the formation of biofilm in bacteria of the genus Arcobacter. A multiplex polymerase chain reaction (PCR) method was introduced and optimized for detecting biofilm while using the intercalating dyes ethidium monoazide (EMA) and propidium monoazide (PMA), first for analysis of strains of the genus Arcobacter from a collection, and then applied to samples of prepared biofilms. The results of the study indicate considerable variability among species of bacteria within the genus Arcobacter. The EMA–PMA PCR method can distinguish viable cells from dead cells and is therefore suitable for determining the viability of cells.
Moose (Alces alces) predation by eastern coyotes (Canislatrans) and eastern coyote × eastern wolf (Canislatrans×Canislycaon) hybrids
Authors: Benson J.F. , Patterson B.R.
Published: October 2013

It has been widely assumed that coyotes (Canis latrans Say, 1823) are incapable of killing adult moose (Alces alces (L., 1758)) and previous studies of coyote predation support this assumption. However, eastern coyotes and eastern coyote × eastern wolf (Canis lycaon Schreber, 1775) are larger than western coyotes and appear to rely on larger prey in some areas. We used a combination of GPS telemetry, genetic analysis, and field investigation to test the hypothesis that eastern coyotes and coyote × wolf hybrids are capable of preying on adult moose in central Ontario. Our hypothesis was supported, as we documented four definitive cases of eastern coyotes and (or) eastern coyote × eastern wolf hybrids killing moose ≥1.5 years old. Predation by coyotes and coyote × wolf hybrids probably does not represent a threat to moose population viability in central Ontario, but our results suggest that researchers and managers in other areas with declining moose populations that are sympatric with eastern coyotes and (or) coyote × wolf hybrids should consider coyote predation as a potential source of mortality.
THE INTERNATIONAL LINEAR COLLIDER
Authors: BARISH BARRY , BRAU JAMES E.
Published: October 2013

In this paper, we describe the key features of the recently completed technical design for the International Linear Collider (ILC), a 200–500 GeV linear electron–positron collider (expandable to 1 TeV) that is based on 1.3 GHz superconducting radio-frequency (SCRF) technology. The machine parameters and detector characteristics have been chosen to complement the Large Hadron Collider physics, including the discovery of the Higgs boson, and to further exploit this new particle physics energy frontier with a precision instrument. The linear collider design is the result of nearly 20 years of R&D, resulting in a mature conceptual design for the ILC project that reflects an international consensus. We summarize the physics goals and capability of the ILC, the enabling R&D and resulting accelerator design, as well as the concepts for two complementary detectors. The ILC is technically ready to be proposed and built as a next generation lepton collider, perhaps to be built in stages beginning as a Higgs factory.
TOPOLOGICAL EFFECTIVE FIELD THEORIES FOR DIRAC FERMIONS FROM INDEX THEOREM
Authors: PALUMBO GIANDOMENICO , CATENACCI ROBERTO , MARZUOLI ANNALISA
Published: October 2013

Dirac fermions have a central role in high energy physics but it is well-known that they emerge also as quasiparticles in several condensed matter systems supporting topological order. We present a general method for deriving the topological effective actions of (3+1)-massless Dirac fermions living on general backgrounds and coupled with vector and axial-vector gauge fields. The first step of our strategy is standard (in the Hermitian case) and consists in connecting the determinants of Dirac operators with the corresponding analytical indices through the zeta-function regularization. Then, we introduce a suitable splitting of the heat kernel that naturally selects the purely topological part of the determinant (i.e., the topological effective action). This topological effective action is expressed in terms of gauge fields using the Atiyah–Singer index theorem which computes the analytical index in topological terms. The main new result of this paper is to provide a consistent extension of this method to the non-Hermitian case, where a well-defined determinant does not exist. Quantum systems supporting relativistic fermions can thus be topologically classified on the basis of their response to the presence of (external or emergent) gauge fields through the corresponding topological effective field theories (TEFTs).
RAMAN SPECTROSCOPY OF TEMPERATURE INDUCED EFFECTS IN FOUR CARBON ALLOTROPES
Authors: JOYA M. R. , ZANATTA A. R. , BARBA-ORTEGA J.
Published: October 2013

In this paper, we report strong variations in the Raman spectra of different carbon allotropes samples, for temperatures ranging from 83 K to 1123 K. The temperature dependence of D and G peak frequencies in the Raman spectrum of diamond, graphite, graphene, and carbon nanoparticles (CNPs) with 20 nm dot-size were investigated. These effects caused by temperature can be estimated from the changes in position [Formula: see text] and in linewidth of peak full width at half maximum (FWHM) G in the Raman spectrum of each sample. The broadening for each allotrope under the same conditions of temperature were: diamond ~ 4 cm-1, graphite ~ 50 cm-1, graphene ~ 5 cm-1 and nanoparticles ~ 7 cm-1. We also used scanning electron microscopy (SEM) to study the morphology and determine the size of the samples. According to the experimental data, the residual structural disorder and stress present in the samples are enhanced with temperature and responds for the observed changes in the Raman spectra. We present a systematic study of the temperature-dependent Raman spectra of four carbon allotropes.
ELECTRONIC STRUCTURES AND MAGNETISM IN Cu-DOPED ZnO MONOLAYER
Authors: PENG YUTING , WEI SHUYI , XIA CONGXIN , JIA YU
Published: October 2013

In this paper, the electronic structures and magnetic properties of the Cu -doped ZnO monolayer are investigated by means of first-principles methods based on density functional theory. Numerical results show that the Cu dopant can induce the half-metallic ferromagnets in the ZnO monolayer due to the strong p–d coupling. In addition, the semiconductor band gap is also decreased when Zn atom is substituted by Cu atom in the ZnO monolayer. Moreover, the formation energy calculations also indicate that it is energy favorable and relatively easier to incorporate Cu atom into the ZnO monolayer under Zn -rich experimental conditions.
FIRST-PRINCIPLES CALCULATION OF MAGNETO-ELECTRONIC STRUCTURE OF MOLECULE-FERROMAGNET HYBRID TUNNEL JUNCTIONS
Authors: ANSARINO MASOUD , RAVAN BAHRAM ABEDI , AHMADIZADEH YADOLLAH
Published: October 2013

In this paper, using first-principles calculations the electronic and magnetic structure of trans- and cis-polyacetylene based magnetic tunnel junctions is investigated. Energy minimization calculations are performed to obtain the equilibrium bonding length at the metal/polymer interfaces. Magnetic proximity-induced spin polarization across the polymeric chains is calculated and it is shown that irrespective of the parallel or anti-parallel magnetic configuration of the electrodes the carbon atoms attaching the Fe electrodes get oppositely polarized. Local density of states calculations reveal that, as a result of being attached to the ferromagnetic leads, states are induced in the energy gap region of molecule's px and py orbitals which infers their contribution in electronic transmission of the device.
STORAGE AND RETRIEVAL OF THE QUANTUM STATE OF A PHOTON WITH TWO CENTRAL FREQUENCIES IN QUANTUM DOTS
Authors: XIE DONG , WANG AN MIN
Published: October 2013

In this paper, a proposal for how to store and retrieve the quantum state of a nonstationary photon wave packet in quantum dots is presented. Here, the input photon with two central frequencies is different from the usual photon. In order to store the quantum state of the input photon more stably, we control the magnetic field to transfer the coherence from electronic spins to nuclear spins. In this paper, we also suggest one method to produce a photon with two central frequencies, and point out a possible way to code quantum information.
PERSISTENT PATTERNS IN MICROTUBULE DIPOLE LATTICES
Authors: NANDI SHUBHENDU , JOHNSON NEIL F. , COHN JOSHUA L.
Published: October 2013

Microtubules (MTs) are cytoskeletal protein polymers orchestrating a host of important cellular functions including, but not limited to, cell support, cell division, cell motility and cell transport. We construct a toy-model of the MT lattice composed of classical vector Ising spins (dipole moments) representing the tubulin molecules, the building block of MTs. Nearest-neighbor (NN) and next-nearest-neighbor (NNN) interactions are considered within an anisotropic dielectric medium. As a consequence of the helical topology, certain spin orientations render the lattice frustrated with NN ferroelectric and NNN antiferroelectric bonds. Mapping the problem to a 2D Ising model and employing Monte Carlo methods we find that frozen clusters of spins exist at human physiological temperatures. This suggests a novel biological mechanism for storing information in living organisms, whereby the classical tubulin spin states become information bits and information gets stored in MTs in a way that is robust to thermal fluctuations.
Changes in translation rate modulate stress-induced damage of diverse proteins
Authors: Kim Heejung , Strange Kevin
Published: October 2013

Proteostasis is the maintenance of the proper function of cellular proteins. Hypertonic stress disrupts proteostasis and causes rapid and widespread protein aggregation and misfolding in the nematode Caenorhabditis elegans. Optimal survival in hypertonic environments requires degradation of damaged proteins. Inhibition of protein synthesis occurs in response to diverse environmental stressors and may function in part to minimize stress-induced protein damage. We recently tested this idea directly and demonstrated that translation inhibition by acute exposure to cycloheximide suppresses hypertonicity-induced aggregation of polyglutamine::YFP (Q35::YFP) in body wall muscle cells. In this article, we further characterized the relationship between protein synthesis and hypertonic stress-induced protein damage. We demonstrate that inhibition of translation reduces hypertonic stress-induced formation and growth of Q35::YFP, Q44::YFP, and α-synuclein aggregates; misfolding of paramyosin and ras GTPase; and aggregation of multiple endogenous proteins expressed in diverse cell types. Activation of general control nonderepressible-2 (GCN-2) kinase signaling during hypertonic stress inhibits protein synthesis via phosphorylation of eukaryotic initiation factor-2α (eIF-2α). Inhibition of GCN-2 activation prevents the reduction in translation rate and greatly exacerbates the formation and growth of Q35::YFP aggregates and the aggregation of endogenous proteins. The current studies together with our previous work provide the first direct demonstration that hypertonic stress-induced reduction in protein synthesis minimizes protein aggregation and misfolding. Reduction in translation rate also serves as a signal that activates osmoprotective gene expression. The cellular proteostasis network thus plays a critical role in minimizing hypertonic stress-induced protein damage, in degrading stress-damaged proteins, and in cellular osmosensing and signaling.
Preference for linoleic acid in obesity-prone and obesity-resistant rats is attenuated by the reduction of CD36 on the tongue
Authors: Chen Christina S.-Y. , Bench Elias M. , Allerton Timothy D. , Schreiber Allyson L. , Arceneaux Kenneth P. , Primeaux Stefany D.
Published: October 2013

Differential sensing of dietary fat and fatty acids by the oral cavity is proposed to regulate the susceptibility to obesity. In the current experiments, animals that differ in their susceptibility to obesity were used to investigate the influence of the oral cavity on the preference for the polyunsaturated fatty acid, linoleic acid. In experiment 1, the preference for differing concentrations of linoleic acid was determined in obesity-prone Osborne-Mendel (OM) and obesity-resistant S5B/Pl (S5B) rats. The preference threshold for linoleic acid was lower in S5B rats, compared with OM rats. To determine whether differences in linoleic acid preference threshold were related to innate strain differences in the fatty acid receptors on the tongue, the expression of GPR120, GPR40, and CD36 on the circumvallate papillae were assessed in OM and S5B rats. Results indicated that the expression of CD36, GPR40, and GPR120 did not differ between these two strains. Numerous studies have examined the role of CD36 on fat intake; therefore, in experiment 3, RNA interference was used to decrease the expression of CD36 on the tongues of OM and S5B rats, and the effect of decreased CD36 expression on linoleic acid preference was determined. CD36 siRNA attenuated linoleic acid preference for the most preferred concentration in both OM and S5B rats. Overall, these data indicate that there are innate differences in the preference threshold for linoleic acid in obesity-prone and obesity-resistant rats. Experimentally reducing the expression of CD36 on the circumvallate papillae attenuated the preference for linoleic acid in both strains.
The direction and role of phenotypic transition between podocytes and parietal epithelial cells in focal segmental glomerulosclerosis
Authors: Sakamoto Kazuo , Ueno Toshiharu , Kobayashi Namiko , Hara Satoshi , Takashima Yasutoshi , Pastan Ira , Matsusaka Taiji , Nagata Michio
Published: October 2013

Focal segmental glomerulosclerosis (FSGS) is a podocyte disease. Among the various histologies of FSGS, active epithelial changes, hyperplasia, as typically seen in the collapsing variant, indicates disease progression. Using a podocyte-specific injury model of FSGS carrying a genetic podocyte tag combined with double immunostaining by different sets of podocytes and parietal epithelial cell (PEC) markers [nestin/Pax8, Wilms' tumor-1 (WT1)/claudin1, and podocalyxin/Pax2], we investigated the direction of epithelial phenotypic transition and its role in FSGS. FSGS mice showed progressive proteinuria and renal dysfunction often accompanied by epithelial hyperplasia, wherein 5-bromo-4-chloro-3-indoyl β-d-galactoside (X-gal)-positive podocyte-tagged cells were markedly decreased. The average numbers of double-positive cells in all sets of markers were significantly increased in the FSGS mice compared with the controls. In addition, the average numbers of double-positive cells for X-gal/Pax8, nestin/Pax8 and podocalyxin/Pax2 staining in the FSGS mice were comparable, whereas those of WT1/claudin1 were significantly increased. When we divided glomeruli from FSGS mice into those with FSGS lesions and those without, double-positive cells tended to be more closely associated with glomeruli without FSGS lesions compared with those with FSGS lesions. Moreover, the majority of double-positive cells appeared to be isolated and very rarely associated with FSGS lesions (1/1,997 glomeruli). This study is the first to show the incidence and localization of epithelial cells with phenotypical changes in FSGS using a genetic tag. The results suggest that the major direction of epithelial phenotypic transition in cellular FSGS is from podocytes to PECs and that these cells were less represented in the active lesions of FSGS.
Demeclocycline attenuates hyponatremia by reducing aquaporin-2 expression in the renal inner medulla
Authors: Kortenoeven Marleen L. A. , Sinke Anne P. , Hadrup Niels , Trimpert Christiane , Wetzels Jack F. M. , Fenton Robert A. , Deen Peter M. T.
Published: October 2013

Binding of vasopressin to its type 2 receptor in renal collecting ducts induces cAMP signaling, transcription and translocation of aquaporin (AQP)2 water channels to the plasma membrane, and water reabsorption from the prourine. Demeclocycline is currently used to treat hyponatremia in patients with the syndrome of inappropriate antidiuretic hormone secretion (SIADH). Demeclocycline's mechanism of action, which is poorly understood, is studied here. In mouse cortical collecting duct (mpkCCD) cells, which exhibit deamino-8-d-arginine vasopressin (dDAVP)-dependent expression of endogenous AQP2, demeclocycline decreased AQP2 abundance and gene transcription but not its protein stability. Demeclocycline did not affect vasopressin type 2 receptor localization but decreased dDAVP-induced cAMP generation and the abundance of adenylate cyclase 3 and 5/6. The addition of exogenous cAMP partially corrected the demeclocycline effect. As in patients, demeclocycline increased urine volume, decreased urine osmolality, and reverted hyponatremia in an SIADH rat model. AQP2 and adenylate cyclase 5/6 abundances were reduced in the inner medulla but increased in the cortex and outer medulla, in the absence of any sign of toxicity. In conclusion, our in vitro and in vivo data indicate that demeclocycline mainly attenuates hyponatremia in SIADH by reducing adenylate cyclase 5/6 expression and, consequently, cAMP generation, AQP2 gene transcription, and AQP2 abundance in the renal inner medulla, coinciding with a reduced vasopressin escape response in other collecting duct segments.
Habenula functional resting-state connectivity in pediatric CRPS
Authors: Erpelding Nathalie , Sava Simona , Simons Laura E. , Lebel Alyssa , Serrano Paul , Becerra Lino , Borsook David
Published: October 2013

The habenula (Hb) is a small brain structure located in the posterior end of the medial dorsal thalamus and through medial (MHb) and lateral (LHb) Hb connections, it acts as a conduit of information between forebrain and brainstem structures. The role of the Hb in pain processing is well documented in animals and recently also in acute experimental pain in humans. However, its function remains unknown in chronic pain disorders. Here, we investigated Hb resting-state functional connectivity (rsFC) in patients with complex regional pain syndrome (CRPS) compared with healthy controls. Twelve pediatric patients with unilateral lower-extremity CRPS (9 females; 10–17 yr) and 12 age- and sex-matched healthy controls provided informed consent to participate in the study. In healthy controls, Hb functional connections largely overlapped with previously described anatomical connections in cortical, subcortical, and brainstem structures. Compared with controls, patients exhibited an overall Hb rsFC reduction with the rest of the brain and, specifically, with the anterior midcingulate cortex, dorsolateral prefrontal cortex, supplementary motor cortex, primary motor cortex, and premotor cortex. Our results suggest that Hb rsFC parallels anatomical Hb connections in the healthy state and that overall Hb rsFC is reduced in patients, particularly connections with forebrain areas. Patients' decreased Hb rsFC to brain regions implicated in motor, affective, cognitive, and pain inhibitory/modulatory processes may contribute to their symptomatology.
Positive Almost Periodic Solution for a Model of Hematopoiesis with Infinite Time Delays and a Nonlinear Harvesting Term
Authors: Zhou Hui , Wang Wen , Zhou Zongfu
Published: October 2013

A generalized model of Hematopoiesis with infinite time delays and a nonlinear harvesting term is investigated. By utilizing a fixed point theorem of the differential equations and constructing a suitable Lyapunov functional, we establish some conditions which guarantee the existence of a unique positive almost periodic solution and the exponential convergence of the system. Finally, we give an example to illustrate the effectiveness of our results.
Electromagnetic Radiations from Heavy Ion Collision
Authors: Mohanty Payal , Ghosh Sabyasachi , Mitra Sukanya
Published: October 2013

In this review, we have discussed the different sources of photons and dileptons produced in heavy ion collision (HIC). The transverse momentum (pT) spectra of photons for different collision energies are analyzed with a view of extracting the thermal properties of the system formed in HIC. We showed the effect of viscosity onpTspectra of produced thermal photons. The dilepton productions from hot hadrons are considered including the spectral change of light vector mesons in the thermal bath. We have analyzed thepTand invariant mass (M) spectra of dileptons for different collision energies too. As the individual spectra are constrained by certain unambiguous hydrodynamical inputs, so we evaluated the ratio of photon to dilepton spectra,Rem, to overcome those quantities. We argue that the variation of the radial velocity extracted fromRemwithMis indicative of a phase transition from the initially produced partons to hadrons. In the calculations of interferometry involving dilepton pairs, it is argued that the nonmonotonic variation of HBT radii with invariant mass of the lepton pairs signals the formation of quark gluon plasma in HIC. Elliptic flow (v2) of dilepton is also studied atsNN=2.76 TeV for 30–40% centrality using the(2+1)dhydrodynamical model.
Study on p-Wave Attenuation in Hydrate-Bearing Sediments Based on BISQ Model
Authors: Li Chuanhui , Feng Kai , Liu Xuewei
Published: October 2013

In hydrate-bearing sediments, the elastic wave attenuation characteristics depend on the elastic properties of the sediments themselves on the one hand, and on the other hand, they also depend on the hydrate occurrence state and hydrate saturation. Since the hydrate-bearing sediments always have high porosity, so they show significant porous medium characteristics. Based on the BISQ porous medium model which is the most widely used model to study the attenuation characteristics in the porous media, we focused on p-wave attenuation in hydrate-bearing sediments in Shenhu Area, South China Sea, especially in specific seismic frequency range, which lays a foundation for the identification of gas hydrates by using seismic wave attenuation in Shenhu Area, South China Sea. Our results depict that seismic wave attenuation is an effective attribute to identify gas hydrates.
Photovoltaic Power Prediction Based on Scene Simulation Knowledge Mining and Adaptive Neural Network
Authors: Niu Dongxiao , Wei Yanan , Chen Yanchao
Published: October 2013

Influenced by light, temperature, atmospheric pressure, and some other random factors, photovoltaic power has characteristics of volatility and intermittent. Accurately forecasting photovoltaic power can effectively improve security and stability of power grid system. The paper comprehensively analyzes influence of light intensity, day type, temperature, and season on photovoltaic power. According to the proposed scene simulation knowledge mining (SSKM) technique, the influencing factors are clustered and fused into prediction model. Combining adaptive algorithm with neural network, adaptive neural network prediction model is established. Actual numerical example verifies the effectiveness and applicability of the proposed photovoltaic power prediction model based on scene simulation knowledge mining and adaptive neural network.
Attribute Reduction in Intuitionistic Fuzzy Concept Lattices
Authors: Pang Jinzhong , Zhang Xiaoyan , Xu Weihua
Published: October 2013

As an effective tool for knowledge discovery, concept lattice has been successfully applied to various fields. And one of the key problems of knowledge discovery is attribute reduction. In order to understand the problems better, the attribute reduction is necessary to perfect the theory as well as expand application of concept lattice. This paper introduces the intuitionistic fuzzy theory into the concept lattice theory and proposes a kind of intuitionistic fuzzy concept lattice. Then, an approach to attribute reduction based on the discernibility matrix is proposed and investigated, which makes the discovery of implicit knowledge easier and the representation simpler in data; furthermore, the theory of concept lattice is perfected. The theory of intuitionistic fuzzy concept lattice is useful and meaningful in view of the complexity and fuzziness of information in real world, and the potential value of dealing with information is expected in the future.
A Secure and Efficient Data Aggregation Framework in Vehicular Sensing Networks
Authors: Du Suguo , Tian Peng , Ota Kaoru , Zhu Haojin
Published: October 2013

Vehicular ad hoc networks support a wide range of promising applications including vehicular sensing networks, which enable vehicles to cooperatively collect and transmit the aggregated traffic data for the purpose of traffic monitoring. The reported literatures mainly focus on how to achieve the data aggregation in dynamic vehicular environment, while the security issue especially on the authenticity and integrity of aggregation results receives less attention. In this study, we introduce a basic aggregation scheme which could aggregate the data and the message authentication codes by using syntactic aggregation and cryptographic aggregation. To tolerate duplicate messages and further improve the aggregation performance, we introduce a secure probabilistic data aggregation scheme based on Flajolet-Martin sketch and sketch proof technique. We also discuss the tradeoff between the bandwidth efficiency and the estimation accuracy. Extensive simulations and analysis demonstrate the efficiency and effectiveness of the proposed scheme.