bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermoelectric properties of topological insulator Bi2Te3, Sb2Te3, and Bi2Se3 thin film quantum wells
Authors: Osterhage Hermann , Gooth Johannes , Hamdou Bacel , Gwozdz Paul , Zierold Robert , Nielsch Kornelius
Published: September 2014

The thermoelectric (TE) figure of merit ZT of topological insulator Bi2Te3, Sb2Te3, and Bi2Se3 thin film quantum wells is calculated for thicknesses below 10 nm, for which hybridization of the surface states as well as quantum confinement in the bulk are individually predicted to enhance ZT. Here, the question is addressed what ZT can be expected from coexisting surface and bulk states in such quantum wells. It is demonstrated that the parallel contributing bulk and surface channels tend to cancel each other out. This is because the surface-to-volume ratios of the thin films prevent the domination of transport through a single channel and because the individual bulk and surface ZTs are optimized at different Fermi levels.
The effects of early time laser drive on hydrodynamic instability growth in National Ignition Facility implosions
Authors: Peterson J. L. , Clark D. S. , Masse L. P. , Suter L. J.
Published: September 2014

Defects on inertial confinement fusion capsule surfaces can seed hydrodynamic instability growth and adversely affect capsule performance. The dynamics of shocks launched during the early period of x-ray driven National Ignition Facility (NIF) implosions determine whether perturbations will grow inward or outward at peak implosion velocity and final compression. In particular, the strength of the first shock, launched at the beginning of the laser pulse, plays an important role in determining Richtmyer-Meshkov (RM) oscillations on the ablation front. These surface oscillations can couple to the capsule interior through subsequent shocks before experiencing Rayleigh-Taylor (RT) growth. We compare radiation hydrodynamic simulations of NIF implosions to analytic theories of the ablative RM and RT instabilities to illustrate how early time laser strength can alter peak velocity growth. We develop a model that couples the RM and RT implosion phases and captures key features of full simulations. We also show how three key parameters can control the modal demarcation between outward and inward growth.
Nonlocal control of electron temperature in short direct current glow discharge plasma
Authors: Demidov V. I. , Kudryavtsev A. A. , Kurlyandskaya I. P. , Stepanova O. M.
Published: September 2014

To demonstrate controlling the electron temperature in nonlocal plasma, experiments have been performed on a short (without positive column) dc glow discharge with a cold cathode by applying different voltages to the conducting discharge wall. The experiments have been performed for low-pressure noble gas discharges. The applied voltage can modify trapping the energetic electrons emitted from the cathode sheath and arising from the atomic and molecular processes in the plasma within the device volume. This phenomenon results in the energetic electrons heating the slow plasma electrons, which consequently modifies the electron temperature. Furthermore, a numerical model of the discharge has demonstrated the electron temperature modification for the above case.
Local characterization of nanostructured high sensitivity piezoelectric BiScO3-PbTiO3 ceramics by piezoresponse force microscopy
Authors: Salazar Norberto , Algueró Miguel , Amorín Harvey , Castro Alicia , Gil Adriana , Ricote Jesús
Published: September 2014

Piezoresponse force microscopy has been used for the local characterization of high sensitivity piezoelectric BiScO3-PbTiO3 ceramics with compositions close to the morphotropic phase boundary, with decreasing grain sizes down to 28 nm. The use of this high resolution technique has allowed not only the analysis of the evolution of the ferroelectric domain configurations, with the disappearance of ferroelastic domains at the nanoscale, but also to establish the existence of correlations among the polarization of adjacent single-domain grains and the formation of inversion superdomains. The effect of the grain size reduction on the piezoelectric coefficients was also studied. Finally, piezoelectric loops have been obtained on the smallest grains, and some distinctive features, such as an atypical clockwise hysteresis is discussed and related to high resistivity grain boundaries.
Interplay between snake and quantum edge states in a graphene Hall bar with a pn-junction
Authors: Milovanović S. P. , Ramezani Masir M. , Peeters F. M.
Published: September 2014

The magneto- and Hall resistance of a locally gated cross shaped graphene Hall bar is calculated. The edge of the top gate is placed diagonally across the center of the Hall cross. Four-probe resistance is calculated using the Landauer-Büttiker formalism, while the transmission coefficients are obtained using the non-equilibrium Green's function approach. The interplay between transport due to edge channels and snake states is investigated. When two edge channels are occupied, we predict oscillations in the Hall and the bend resistance as function of the magnetic field, which are a consequence of quantum interference between the occupied snake states.
Modelling methane emissions from remotely collected liveweight data and faecal near-infrared spectroscopy in beef cattle
Authors: González L. A. , Charmley E. , Henry B. K.
Published: September 2014

The objective of the present study was to develop a model-data fusion approach using remotely collected liveweight (LW) data from individual animals (weighing station placed at the water trough) and evaluate the potential for these data from frequent weighing to increase the accuracy of estimates of methane emissions from beef cattle grazing tropical pastures. Remotely collected LW data were used to calculate daily LW change (LWC), i.e. growth rate on a daily basis, and then to predict feed intake throughout a 342-day grazing period. Feed intake and diet dry matter digestibility (DMD) from faecal near-infrared spectroscopy analysis were used to predict methane emissions using methods for both tropical and temperate cattle as used in the Australian national inventory (Commonwealth of Australia 2014). The remote weighing system captured both short- and long-term environmental (e.g. dry and wet season, and rainfall events) and management effects on LW changes, which were then reflected in estimated feed intake and methane emissions. Large variations in all variables, measured and predicted, were found both across animals and throughout the year. Methane predictions using the official national inventory model for tropical cattle resulted in 20% higher emissions than those for temperate cattle. Predicted methane emissions based on a simulation using only initial and final LW and assuming a linear change in LW between these two points were 7.5% and 5.8% lower than those using daily information on LW from the remote weighing stations for tropical and temperate cattle, respectively. Methane emissions and feed intake can be predicted from remotely collected LW data in near real-time on a daily basis to account for short- and long-term variations in forage quality and intake. This approach has the potential to provide accurate estimates of methane emissions at the individual animal level, making the approach suitable for grazing livestock enterprises wishing to participate in carbon markets and accounting schemes.
Proteopathic tau seeding predicts tauopathy in vivo
Authors: Holmes Brandon B. , Furman Jennifer L. , Mahan Thomas E. , Yamasaki Tritia R. , Mirbaha Hilda , Eades William C. , Belaygorod Larisa , Cairns Nigel J. , Holtzman David M. , Diamond Marc I.
Published: September 2014

Significance

Prion-like propagation of proteopathic seeds may underlie the progression of neurodegenerative diseases, including the tauopathies and synucleinopathies. We aimed to construct a versatile and simple cell assay to sensitively and specifically detect proteopathic seeding activity. Using a combination of FRET flow cytometry and a tau monoclonal FRET biosensor cell line, we report seed detection in the femtomolar range. This assay is easily applied to human brain homogenates and selectively responds to Alzheimer's disease but not Huntington's disease brains. By comparing seeding activity in a mouse model of human tauopathy, we demonstrate detection of proteopathic seeding far in advance of standard histopathological markers. Proteopathic seeding is thus an early marker of tauopathy, consistent with a causal role for tau seeds in neurodegeneration.
Frequency-modulated solar rotational periodicity of geomagnetic indices
Authors: Chang Heon-Young
Published: September 2014

Many attempts have been made to search for various timescales in the power spectrum of geomagnetic indices so that common periodicities in the solar activity and geomagnetic activity indices are identified. The spectral behavior of geomagnetic activity parameters may also provide invaluable information about physical processes involved. In this study we attempt to demonstrate that the frequency modulation associated with a long-term variation may cause extra sidelobes around the principal peak with a periodicity of ∼ 27 d in the observed power spectrum of geomagnetic activity indices, and/or may even split the peak into two adjacent peaks. We employ a straightforward model of an oscillation frequency-modulated by an arbitrary agent to consider the solar rotational periodicity of geomagnetic indices. As a result, we have found that the peak with the periodicity of ∼ 27 d in the observed power spectrum of geomagnetic indices seems likely frequency-modulated by the amount of 0.0026 d−1 which corresponds to a ∼ 1 yr period. We thus suggest that the fundamental period of the periodic perturbative agent is much longer than a year according to our analysis. Finally, we conclude by discussing the implications of what we have found.
Improving the moment approach for astrometric binaries: possible application to Cygnus X-1
Authors: Yamada Kei , Yamaguchi Masaki S. , Asada Hideki , Gouda Naoteru
Published: September 2014

A moment approach for orbital determinations of astrometric binaries from astrometric observations alone has been recently studied for a low signal-to-noise ratio (Iwama et al. 2013, PASJ, 65, 2). Through avoiding a direct use of the time-consuming Kepler equation, temporal information is taken into account to increase the accuracy of statistical moments. As numerical tests, 100 realizations are done and the mean value and the standard deviation are also evaluated. For a semimajor axis, the difference between the mean of the recovered values and the true value decreases to less than a tenth in the case of 10000 observed points. Therefore, the present approach works better than the previous one for orbital determinations when one has a large number of observed points. The present approach is thus applicable to Cyg X-1.
Superoutburst of SDSS J090221.35+381941.9: First measurement of mass ratio in an AM CVn-type object using growing superhumps
Authors: Kato Taichi , Ohshima Tomohito , Denisenko Denis , Dubovsky Pavol A. , Kudzej Igor , Stein William , de Miguel Enrique , Henden Arne , Miller Ian , Antonyuk Kirill , Antonyuk Oksana , Pit Nikolaj , Sosnovskij Aleksei , Baklanov Alex , Babina Julia , Pavlenko Elena P. , Matsumoto Kazunari , Fukushima Daiki , Takenaka Megumi , Kawabata Miho , Sakai Daisuke , Maeda Kazuki , Matsuda Risa , Matsumoto Katsura , Littlefield Colin , Oksanen Arto , Itoh Hiroshi , Masi Gianluca , Nocentini Francesca , Schmeer Patrick , Pickard Roger D. , Kiyota Seiichiro , Dvorak Shawn , Ulowetz Joseph , Maeda Yutaka , Michel Raúl , Shugarov Sergey Yu. , Chochol Drahomir , Novák Rudolf
Published: September 2014

We report on a superoutburst of the AM CVn-type object SDSS J090221.35+381941.9 [J0902; orbital period 0.03355(6) d] in 2014 March–April. The entire superoutburst consisted of a precursor outburst and the main superoutburst, followed by a short rebrightening. During the rising phase of the main superoutburst, we detected growing superhumps (stage A superhumps) with a period of 0.03409(1) d. During the plateau phase of the superoutburst, superhumps with a shorter period (stage B superhumps) were observed. Using the orbital period and the period of stage A superhumps, we were able to measure the dynamical precession rate of the accretion disk at the 3:1 resonance, and obtained a mass ratio (q) of 0.041(7). This is the first successful measurement of the mass ratio in an AM CVn-type object accomplished by the recently developed stage A superhump method. The value is generally in agreement with that based on the theoretical evolutionary model. The orbital period of J0902 is the longest among those of the outbursting AM CVn-type objects, and a period on the borderline between the outbursting system and the system with a stable cool disk appears to be longer than one supposed.
Hepatic Hepcidin Protects against Polymicrobial Sepsis in Mice by Regulating Host Iron Status
Authors: Zeng CongLi , Chen QiXing , Zhang Kai , Chen QingHua , Song ShengWen , Fang XiangMing
Published: September 2014

AbstractAbstract

Disruption of mouse hepatic hepcidin expression led to significant increases in organ damage and mortality when sepsis was produced. Decreasing the iron levels in these mice improved survival.

Background:

Hepcidin is a master regulator of iron metabolism primarily produced by the liver. Markedly increased hepcidin levels have been observed in septic individuals, while decreased hepatic hepcidin expression has been demonstrated in liver diseases that tend to develop into sepsis. However, the role of liver hepcidin in sepsis remains unknown.

Methods:

Mouse hepatic hepcidin expression was silenced using adenovirus-mediated hepcidin-specific short hairpin RNA injected via the tail vein. Sepsis was induced by cecal ligation and puncture, and the outcome (n = 23 for hepcidin knockdown mice, n = 15 for controls) and pathogenic changes (n = 5) related to sepsis were evaluated. The impact of alteration of iron status on the survival rate of hepatic hepcidin knockdown mice (n = 18 to 19) was also investigated.

Results:

Disruption of liver hepcidin expression increased serum iron level (537.8 ± 28.1 μg/dl [mean ± SD] vs. 235.9 ± 62.2 μg/dl; P < 0.05) and reduced iron content in the spleen macrophages at the steady state. Hepatic hepcidin knockdown mice not only showed increased 7-day mortality (73.9% vs. 46.7%; P < 0.05), but also had exacerbated organ damage and oxidative stress, as well as compromised host inflammatory responses and bacterial clearance at 24 h after polymicrobial sepsis. Treating the hepatic hepcidin knockdown mice with low-iron diet plus iron chelation decreased systemic iron content (serum level: 324.0 ± 67.4 μg/dl vs. 517.4 ± 13.4 μg/dl; P < 0.05) and rescued the mice from lethal sepsis (7-day survival: 36.8% vs. 83.3%; P < 0.01).

Conclusions:

Hepatic hepcidin plays an important role in sepsis through regulation of iron metabolism. The findings may have potential therapeutic implications for liver diseases in which hepcidin expression is decreased.
Pseudomonas aeruginosa bacteraemia: independent risk factors for mortality and impact of resistance on outcome
Authors: Dantas Raquel Cavalcanti , Ferreira Melina Lorraine , Gontijo-Filho Paulo Pinto , Ribas Rosineide Marques
Published: September 2014

The rates of multidrug-resistant, extensively drug-resistant and pandrug-resistant isolates amongst non-fermenting Gram-negative bacilli, particularlyPseudomonas aeruginosa, have risen worldwide. The clinical consequence of resistance and the impact of adverse treatment on the outcome of patients withP. aeruginosabacteraemia remain unclear. To better understand the predictors of mortality, the clinical consequence of resistance and the impact of inappropriate therapy on patient outcomes, we analysed the first episode ofP. aeruginosabacteraemia in patients from a Brazilian tertiary-care hospital during the period from May 2009 to August 2011. Antimicrobial susceptibility testing was conducted; phenotypic detection of metallo-β-lactamase (MBL) and PCR of MBL genes were performed on carbapenem-resistant strains. Amongst the 120P. aeruginosaisolates, 45.8 % were resistant to carbapenem and 36 strains were tested for MBL detection. A total of 30 % were phenotypically positive and, of these, 77.8 % expressed an MBL gene,blaSPM-1(57 %) andblaVIM-type (43 %). The resistance rates to ceftazidime, cefepime, piperacillin/tazobactam, carbapenem, fluoroquinolone and aminoglycoside were 55, 42.5, 35, 45.8, 44 and 44 %, respectively. Previous antibiotic use, length of a hospital stay ≥30 days prior toP. aeruginosa, haemodialysis, tracheostomy, pulmonary source of bacteraemia and Intensive Care Unit admission were common independent risk factors for antimicrobial resistance. Cefepime resistance, multidrug resistance and extensive drug resistance were independently associated with inappropriate therapy, which was an important predictor of mortality, being synergistic with the severity of the underlying disease.
Evaluation of reported cases of pertussis: epidemiological study in a large city in Spain
Authors: Solano Rubén , Rius Cristina , Simón Pere , Manzanares-Laya Sandra , Ros Miriam , Toledo Diana , Domíngez Àngela , Caylà Joan A.
Published: September 2014

We retrospectively analysed the incidence rate of reported cases of pertussis in Barcelona during 2009–2012 according to age, sex, type of medical centre and vaccination status. We included 748 confirmed or suspected cases, 613 (82.0 %) of which were confirmed by laboratory testing and the remaining 135 (18.0 %) by epidemiological evidence. The highest reported incidence of pertussis was amongst <1 year olds [96.1 per 100 000 person-years, 95 % confidence interval (CI): 84.3–109.1]. The majority of confirmed and suspected cases were reported in 2011 and 2012, and the total incidence (confirmed or suspected) was 6.3 (95 % CI: 5.6–6.9) and 4.2 (95 % CI: 3.6–4.7) per 100 000 person-years, respectively. Incidence increased significantly (P = 0.001) in 2011–2012 compared with 2009. Most confirmed cases occurred in children <1 year old (87.9 %). Cases were confirmed by real-time (RT)-PCR (87.5 %; 95 % CI: 81.3–87.6) and bacterial culture (13.7 %; 95 % CI: 11.0–17.1). We recommend performing RT-PCR in suspected cases with no epidemiological link to a confirmed case.
Development of a multiplex PCR assay for identification of Klebsiella pneumoniae hypervirulent clones of capsular serotype K2
Authors: Bialek-Davenet Suzanne , Criscuolo Alexis , Ailloud Florent , Passet Virginie , Nicolas-Chanoine Marie-Hélène , Decré Dominique , Brisse Sylvain
Published: September 2014

Hypervirulent Klebsiella pneumoniae isolates of capsular serotype K2 (hvKP-K2) that cause community-acquired invasive infections represent several unrelated clones, which all belong to phylogenetic group KpI. These clones can be recognized using multilocus sequence typing and genomic analyses, but no rapid method currently exists to differentiate them. In this work, a multiplex PCR assay was developed to identify three hvKP-K2 groups: (i) sequence type (ST)86; (ii) ST380 and ST679 (i.e. clonal group 380); and (iii) ST65 and ST375. A specific genetic marker, Kp50233, allowing K. pneumoniae sensu stricto (corresponding to phylogroup KpI) to be distinguished from closely related species, was included in the assay. This PCR assay will be useful in better defining the epidemiology and clinical features of emerging virulent K. pneumoniae clones.
Antibacterial activity of Pinus elliottii and its major compound, dehydroabietic acid, against multidrug-resistant strains
Authors: Leandro Luís Fernando , Cardoso Miguel Jorge Oliveira , Silva Sandro Donizeti Caetano , Souza Maria Gorete Mendes , Veneziani Rodrigo Cassio Sola , Ambrosio Sergio Ricardo , Martins Carlos Henrique Gomes
Published: September 2014

Antibiotic-resistant bacteria have emerged from the widespread use of antibiotics worldwide and have prompted the search for new sources of antimicrobial substances.Pinusspp. contain several bioactive compounds consisting mainly of terpenes, terpenoids and some other aromatic and aliphatic constituents. These compounds exert important biological effects, and pine oils have found wide application in the industry. In the present study, we have evaluated the potential activity of the resin-oil ofPinus elliottiiand its major compound dehydroabietic acid (DA) against multiresistant bacteria by MIC, minimum bactericidal concentration and time-kill assays. The MIC of the resin-oil ofP. elliottiivaried between 25 and 100 µg ml−1. As for DA, the MIC and minimum bactericidal concentration varied between 6.25 and 50 and between 6.25 and 100 µg ml−1, respectively. The time-kill assay conducted with DA at 6.25 µg ml−1evidenced bactericidal activity againstStaphylococcus epidermidis(American Type Culture Collection 14990) within 24 h. On the basis of these results, the resin-oil ofP. elliottiiand its major compound DA play an important part in the search for novel sources of agents that can act against multiresistant bacteria.
Bioinformatics analysis and genetic diversity of the poliovirus
Authors: Liu Yanhan , Ma Tengfei , Liu Jianzhu , Zhao Xiaona , Cheng Ziqiang , Guo Huijun , Wang Shujing , Xu Ruixue
Published: September 2014

Poliomyelitis, a disease which can manifest as muscle paralysis, is caused by the poliovirus, which is a human enterovirus and member of the family Picornaviridae that usually transmits by the faecal–oral route. The viruses of the OPV (oral poliovirus attenuated-live vaccine) strains can mutate in the human intestine during replication and some of these mutations can lead to the recovery of serious neurovirulence. Informatics research of the poliovirus genome can be used to explain further the characteristics of this virus. In this study, sequences from 100 poliovirus isolates were acquired from GenBank. To determine the evolutionary relationship between the strains, we compared and analysed the sequences of the complete poliovirus genome and the VP1 region. The reconstructed phylogenetic trees for the complete sequences and the VP1 sequences were both divided into two branches, indicating that the genetic relationships of the whole poliovirus genome and the VP1 sequences are very similar. This branching indicates that the virulence and pathogenicity of poliomyelitis may be associated with the VP1 region. Sequence alignment of the VP1 region revealed numerous mutation sites in which mutation rates of >30 % were detected. In a group of strains recorded in the USA, mutation sites and mutation types were the same and this may be associated with their distribution in the evolutionary tree and their genetic relationship. In conclusion, the genetic evolutionary relationships of poliovirus isolate sequences are determined to a great extent by the VP1 protein, and poliovirus strains located on the same branch of the phylogenetic tree contain the same mutation spots and mutation types. Hence, the genetic characteristics of the VP1 region in the poliovirus genome should be analysed to identify the transmission route of poliovirus and provide the basis of viral immunity development.
Effect of carbapenem consumption patterns on the molecular epidemiology and carbapenem resistance of Acinetobacter baumannii
Authors: Mózes Julianna , Ebrahimi Fatemeh , Gorácz Orsolya , Miszti Cecília , Kardos Gábor
Published: September 2014

This study investigated the molecular epidemiology of Acinetobacter baumannii in the University of Debrecen in relation to antibiotic consumption. Overall and ward-specific antibiotic consumption was measured by the number of defined daily doses (DDD) per 100 bed-days between 2002 and 2012. Consumption was analysed against the number of A. baumannii positive patients per 100 bed-days, number of isolates per positive sample, and proportion of carbapenem resistant A. baumannii, using time-series analysis. Altogether 160 A. baumannii isolates from different wards were collected and analysed. Carbapenemase genes blaOXA-23-like
, blaOXA-24-like
, blaOXA-48-like
, blaOXA-51-like
, blaOXA-58-like
and integrons were sought by PCR. Relatedness of isolates was assessed by PFGE. Prevalence and carbapenem resistance of A. baumannii were statistically associated with carbapenem consumption. Prevalence data followed carbapenem usage with three quarterly lags (r = 0.51–0.53, P<0.001), and meropenem and ertapenem, but not imipenem usage, affected prevalence. Colistin usage, in turn, lagged behind prevalence with one lag (r = 0.68–0.70, P<0.001). Six clusters were identified; the neurology ward with the lowest carbapenem consumption was associated with the carbapenem-susceptible cluster, as well as with the carbapenem-susceptible isolates in the cluster with variable susceptibility. Wards with high carbapenem usage almost exclusively harboured isolates from carbapenem-resistant clusters. All clusters were dominated by isolates of one or two wards, but most wards were represented in multiple clusters. Increases in prevalence and carbapenem resistance of A. baumannii were associated with usage of meropenem and ertapenem but not of imipenem, which led to the spread of multiple clones in the University.
WFABC: a Wright-Fisher ABC-based approach for inferring effective population sizes and selection coefficients from time-sampled data
Authors: Foll Matthieu , Shim Hyunjin , Jensen Jeffrey D.
Published: September 2014

With novel developments in sequencing technologies, time-sampled data are becoming more available and accessible. Naturally, there have been efforts in parallel to infer population genetic parameters from these datasets. Here, we compare and analyze four recent approaches based on the Wright-Fisher model for inferring selection coefficients (s) given effective population size (Ne), with simulated temporal datasets. Furthermore, we demonstrate the advantage of a recently proposed ABC-based method that is able to correctly infer genome-wide average Ne from time-serial data, which is then set as a prior for inferring per-site selection coefficients accurately and precisely. We implement this ABC method in a new software and apply it to a classical time-serial dataset of the medionigra genotype in the moth Panaxia dominula. We show that a recessive lethal model is the best explanation for the observed variation in allele frequency by implementing an estimator of the dominance ratio (h).
Market and technology orientations for service delivery innovation: the link of innovative competence
Authors: Tsou Hung-Tai , Chen Ja-Shen , Liao Wen-Hsuan
Published: September 2014

Purpose

– The purpose of this paper is to deploy an alternative way, drawing upon research in service innovation, to predict service delivery innovation from the extents of market and technology orientations and innovative competence.

Design/methodology/approach

– Five hypotheses were proposed. A two-part questionnaire was developed. One part of the questionnaire was completed by the sales manager and the other part by the marketing manager of select companies. The questionnaires were distributed to 533 information technology companies in Taiwan. Of the 533 questionnaires returned, 160 questionnaires were deemed usable. This study uses the partial least square analysis to test the hypotheses.

Findings

– Proactive market orientation and technology orientation affect exploratory and exploitative innovative competences; but, only exploitative innovation competence affects service delivery innovation.

Practical implications

– The findings indicate that managers need to understand the market trends and the technology availability and be able to customize corresponding service/product features which can further lead to stimulate exploitative innovative competence and facilitate service delivery innovation.

Originality/value

– The paper is among the first attempts to examine how market and technology orientations affect innovative competence and service delivery innovation. In addition, this study provides the explanatory variance missing in the literature that has not examined the black box relationship between market and technology orientations and service delivery innovation.
Hepatitis C virus infection and the risk of Sjögren or sicca syndrome: a meta‐analysis
Authors: Wang Yan , Dou Hengli , Liu Guowei , Yu Lili , Chen Shimin , Min Yan , Zhao Kanghai , Wang Xingjuan , Hu Chengjin
Published: September 2014

Previous studies have suggested an association between hepatitis C virus (HCV) infection and the development of Sjögren's syndrome (SS), also known as sicca syndrome. The main objective of this study was to summarize the existing evidence and quantitatively evaluate the association between hepatitis C virus infection and SS/sicca syndrome by performing a meta‐analysis of observational studies. MEDLINE and PubMed (January 1980–August 2013) were searched to identify relevant studies in English. Outcomes were calculated and are reported as odds risk (OR) and 95% CIs based on a random‐effects model. Heterogeneity was assessed with I2 statistics. Quality assessment was performed with the Newcastle–Ottawa scale. Based on meta‐analysis of five cross‐sectional and five cohort studies, a significant positive relationship between HCV infection and development of SS/sicca syndrome was found, the pooled random effects OR being 3.31 (95% CI, 1.46–7.48; P < 0.001). In subset analyses, the studies that used European diagnostic criteria showed a higher summary OR than did studies that adopted other diagnostic criteria. When the data were stratified by source of controls, significant associations were also observed when healthy people (OR = 9.44; 95% CI = 2.67–33.40; P = 0.204) or subjects with hepatitis B virus infection (OR = 6.57; 95% CI = 1.21–35.57; P = 0.5) were used as controls, but not when the controls were hospital‐based (OR = 0.99; 95% CI = 0.61–1.61; P = 0.169). In summary, the findings suggest that HCV infection is associated with SS/sicca syndrome. The observed increased risk in studies in which European diagnostic criteria and healthy controls were used and the decreased risk in studies with hospital‐based controls may be attributable to selection bias or other unknown factors.
Abuse potential and adverse cognitive effects of mitragynine (kratom)
Authors: Yusoff Nurul H. M. , Suhaimi Farah W. , Vadivelu Raja K. , Hassan Zurina , Rümler Anne , Rotter Andrea , Amato Davide , Dringenberg Hans C. , Mansor Sharif M. , Navaratnam Visweswaran , Müller Christian P.
Published: September 2014

Mitragynine is the major psychoactive alkaloid of the plant kratom/ketum. Kratom is widely used in Southeast Asia as a recreational drug, and increasingly appears as a pure compound or a component of ‘herbal high’ preparations in the Western world. While mitragynine/kratom may have analgesic, muscle relaxant and anti‐inflammatory effects, its addictive properties and effects on cognitive performance are unknown. We isolated mitragynine from the plant and performed a thorough investigation of its behavioural effects in rats and mice. Here we describe an addictive profile and cognitive impairments of acute and chronic mitragynine administration, which closely resembles that of morphine. Acute mitragynine has complex effects on locomotor activity. Repeated administration induces locomotor sensitization, anxiolysis and conditioned place preference, enhances expression of dopamine transporter‐ and dopamine receptor‐regulating factor mRNA in the mesencephalon. While there was no increase in spontaneous locomotor activity during withdrawal, animals showed hypersensitivity towards small challenging doses for up to 14 days. Severe somatic withdrawal signs developed after 12 hours, and increased level of anxiety became evident after 24 hours of withdrawal. Acute mitragynine independently impaired passive avoidance learning, memory consolidation and retrieval, possibly mediated by a disruption of cortical oscillatory activity, including the suppression of low‐frequency rhythms (delta and theta) in the electrocorticogram. Chronic mitragynine administration led to impaired passive avoidance and object recognition learning. Altogether, these findings provide evidence for an addiction potential with cognitive impairments for mitragynine, which suggest its classification as a harmful drug.
Role of Cytokine Signaling in Group B Streptococcus‐Stimulated Expression of Human Beta Defensin‐2 in Human Extraplacental Membranes
Authors: Boldenow Erica , Hogan Kelly A. , Chames Mark C. , Aronoff David M. , Xi Chuanwu , Loch‐Caruso Rita
Published: September 2014

Problem

Group B Streptococcus (GBS) is a leading cause of neonatal morbidity and mortality. We tested the hypothesis that the choriodecidua plays a role in GBS‐stimulated human beta defensin(HBD)‐2 increases in amnion cells through a secreted factor of choriodecidual origin.

Method of study

Human amnion epithelial cells were treated with choriodecidual GBS‐conditioned medium, live GBS, lipoteichoic acid (LTA), or lipopolysaccharide (LPS), with and without IL‐1 inhibitors.

Results

Choriodecidual tissue punches released IL‐1α and IL‐1β in response to GBS and this medium significantly stimulated release of HBD‐2 by amnion cell cultures. Inhibitors of IL‐1 significantly impaired the release of HBD‐2 from amnion cells treated with GBS choriodecidual conditioned medium. Direct stimulation of amnion cells with GBS, LTA, or LPS did not increase HBD‐2 release.

Conclusion

Paracrine signaling involving IL‐1 of choriodecidual origin is likely a critical driver for amnion HBD‐2 increases in response to GBS infection of extraplacental membranes.
Pulmonary hypertension and its management in patients undergoing non‐cardiac surgery
Authors: Pilkington S. A. , Taboada D. , Martinez G.
Published: September 2014

Pulmonary hypertension is a complex disorder of the pulmonary vasculature that leads to increased peri‐operative morbidity and mortality. Non‐cardiac surgery constitutes a significant risk in patients with pulmonary hypertension. The management of right ventricular failure is inherently challenging and fraught with life‐threatening consequences. A thorough understanding of the pathophysiology, the severity of the disease and its treatment modalities is required to deliver optimal peri‐operative care. This review provides an evidence‐based overview of the definition, classification, pathophysiology, diagnosis and treatment of pulmonary hypertension and focuses on the peri‐operative management and treatment of pulmonary hypertensive crises in a non‐cardiac setting.
Blocking blue light during mania – markedly increased regularity of sleep and rapid improvement of symptoms: a case report
Authors: Henriksen Tone EG , Skrede Silje , Fasmer Ole Bernt , Hamre Børge , Grønli Janne , Lund Anders
Published: September 2014

Objective

Available pharmacological treatment of mania is insufficient. Virtual darkness therapy (blue light‐blocking treatment by means of orange‐tinted glasses) is a promising new treatment option for mania. The basis for this might be the recently identified blue light‐sensitive retinal photoreceptor, which is solely responsible for light stimulus to the circadian master clock. This is the first case report describing the clinical course of a closely monitored, hospitalized patient in a manic episode first receiving clear‐lensed, and then blue light‐blocking glasses.

Methods

A 58‐year‐old Caucasian man, with bipolar I disorder and three previous manic episodes, was hospitalized during a manic episode. In addition to pharmacological treatment, he was treated with clear‐lensed glasses for seven days, then one day without glasses, followed by six days of blue light‐blocking glasses. During the entire observational period, he wore an actigraph with internal light sensors.

Results

Manic symptoms were unaltered during the first seven days. The transition to the blue‐blocking regime was followed by a rapid and sustained decline in manic symptoms accompanied by a reduction in total sleep, a reduction in motor activity during sleep intervals, and markedly increased regularity of sleep intervals. The patient's total length of hospital stay was 20 days shorter than the average time during his previous manic episodes.

Conclusions

The unusually rapid decline in symptoms, accompanied by uniform sleep parameter changes toward markedly increased regularity, suggest that blue‐blockers might be targeting a central mechanism in the pathophysiology of mania that needs to be explored both in clinical research and in basic science.
Multiple independent IgE epitopes on the highly allergenic grass pollen allergen Phl p 5
Authors: Levin M. , Rotthus S. , Wendel S. , Najafi N. , Källström E. , Focke‐Tejkl M. , Valenta R. , Flicker S. , Ohlin M.
Published: September 2014

Background

Group 5 allergens are small proteins that consist of two domains. They belong to the most potent respiratory allergens.

Objective

To determine the binding sites and to study allergic patients' IgE recognition of the group 5 allergen (Phl p 5) from timothy grass pollen using human monoclonal IgE antibodies that have been isolated from grass pollen allergic patients.

Methods

Using recombinant isoallergens, fragments, mutants and synthetic peptides of Phl p 5, as well as peptide‐specific antibodies, the interaction of recombinant human monoclonal IgE and Phl p 5 was studied using direct binding and blocking assays. Cross‐reactivity of monoclonal IgE with group 5 allergens in several grasses was studied and inhibition experiments with patients' polyclonal IgE were performed.

Results

Monoclonal human IgE showed extensive cross‐reactivity with group 5 allergens in several grasses. Despite its small size of 29 kDa, four independent epitope clusters on isoallergen Phl p 5.0101, two in each domain, were recognized by human IgE. Isoallergen Phl p 5.0201 carried two of these epitopes. Inhibition studies with allergic patients' polyclonal IgE suggest the presence of additional IgE epitopes on Phl p 5.

Conclusions & Clinical Relevance

Our results reveal the presence of a large number of independent IgE epitopes on the Phl p 5 allergen explaining the high allergenic activity of this protein and its ability to induce severe allergic symptoms. High‐density IgE recognition may be a general feature of many potent allergens and form a basis for the development of improved diagnostic and therapeutic procedures in allergic disease.
Normosmic idiopathic hypogonadotropic hypogonadism due to a novel homozygous nonsense c.C969A (p.Y323X) mutation in the KISS1R gene in three unrelated families
Authors: Demirbilek Huseyin , Ozbek M. Nuri , Demir Korcan , Kotan L. Damla , Cesur Yasar , Dogan Murat , Temiz Fatih , Mengen Eda , Gurbuz Fatih , Yuksel Bilgin , Topaloglu A. Kemal
Published: September 2014

Objective

The spectrum of genetic alterations in cases of hypogonadotropic hypogonadism continue to expand. However, KISS1R mutations remain rare. The aim of this study was to understand the molecular basis of normosmic idiopathic hypogonadotropic hypogonadism.

Methods

Clinical characteristics, hormonal studies and genetic analyses of seven cases with idiopathic normosmic hypogonadotropic hypogonadism (nIHH) from three unrelated consanguineous families are presented.

Results

One male presented with absence of pubertal onset and required surgery for severe penoscrotal hypospadias and cryptorchidism, while other two males had absence of pubertal onset. Two of four female cases required replacement therapy for pubertal onset and maintenance, whereas the other two had spontaneous pubertal onset but incomplete maturation. In sequence analysis, we identified a novel homozygous nonsense (p.Y323X) mutation (c.C969A) in the last exon of the KISS1R gene in all clinically affected cases.

Conclusions

We identified a homozygous nonsense mutation in the KISS1R gene in three unrelated families with nIHH, which enabled us to observe the phenotypic consequences of this rare condition. Escape from nonsense‐mediated decay, and thus production of abnormal proteins, may account for the variable severity of the phenotype. Although KISS1R mutations are extremely rare and can cause a heterogeneous phenotype, analysis of the KISS1R gene should be a part of genetic analysis of patients with nIHH, to allow better understanding of phenotype–genotype relationship of KISS1R mutations and the underlying genetic basis of patients with nIHH.
Association between habitual physical activity and brown adipose tissue activity in individuals undergoing PET‐CT scan
Authors: Dinas Petros C. , Nikaki Alexandra , Jamurtas Athanasios Z. , Prassopoulos Vassilios , Efthymiadou Roxani , Koutedakis Yiannis , Georgoulias Panagiotis , Flouris Andreas D.
Published: September 2014

Objective

Augmented brown adipose tissue (BAT) mass and activity lead to higher basic metabolic rate which is beneficial against obesity. Our aim was to investigate whether habitual (i.e. usual weekly participation) physical activity is linked with BAT activity and mass in humans, in a group of patients undergoing 18F‐fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) scanning.

Design

Cross‐sectional study.

Patients

Forty patients with cancer [26 male; 14 female; age 52·7 ± 17·5; body mass index (BMI) 26·4 ± 4·5].

Measurements

Patients completed the ‘usual week’ form of the International Physical Activity Questionnaire and underwent assessment of BAT activity/mass via 18F‐fluorodeoxyglucose PET/CT.

Results

We detected a significant association between habitual physical activity (METs‐minute/week) and BAT activity [normalized by body weight (BW) (τ = 0·28, P = 0·02), body surface area (BSA) (τ = 0·29, P = 0·02) and lean body mass (LBM) (τ = 0·38, P = 0·002)]. We also found a significant negative relationship between BMI and BAT activity [normalized by BW (τ = −0·30, P = 0·006), BSA (τ = −0·31, P = 0·004) and LBM (τ = −0·45, P = 0·001)] as well as a significant negative relationship between age and BAT activity [normalized by LBM (τ = −0·28, P = 0·01)]. The results also indicate significant differences between low/moderate/high levels of habitual physical activity and BAT activity (P < 0·05). Moreover, BAT activity was different across the BMI categories (normal/overweight/obese) in both sexes (P < 0·05). Finally, BAT activity was greater in women than in men (P < 0·05).

Conclusions

Increased participation in habitual physical activity is associated with higher BAT activity. Moreover, individuals with normal BMI demonstrate higher BAT activity compared to overweight and obese individuals. Finally, age is inversely linked with BAT activity, while women demonstrate higher BAT activity than men.
Revised criteria for PCOS in WHO Group II anovulatory infertility – a revival of hypothalamic amenorrhoea?
Authors: Lauritsen Mette Petri , Pinborg Anja , Loft Anne , Petersen Jørgen Holm , Mikkelsen Anne Lis , Bjerge Marianne Rich , Nyboe Andersen Anders
Published: September 2014

Objective

To evaluate revised criteria for polycystic ovarian morphology (PCOM) in the diagnosis of polycystic ovary syndrome (PCOS) in anovulatory infertility.

Design

Prospective cohort study.

Patients

WHO Group II anovulatory infertile women (n = 75).

Measurements

Clinical, sonographic and endocrine parameters, including anti‐Müllerian hormone (AMH).

Results

The Rotterdam criteria for PCOM (antral follicle count (AFC) ≥12 and/or ovarian volume >10 ml) were fulfilled in 93% of the women. The PCOM prevalence was 68% when increasing the threshold to AFC >20 and 76% according to an AMH‐based threshold of >35 pmol/l. The most recently proposed AFC ≥ 25 threshold reduced the PCOM prevalence to 52% (n = 39), leaving 48% (n = 36) without features of PCOM. Comparing the 36 women with non‐PCOM with the 39 women in the PCOM group according to AFC ≥ 25, 22% vs 59% (P = 0·001) had serum LH >10 IU/l, 11% vs 41% (P = 0·003) had an LH/FSH ratio >2 and 19% vs 41% (P = 0·04) had hirsutism and/or elevated total testosterone, free testosterone, and/or androstenedione. The non‐PCOM group included significantly more women with secondary infertility. The median AMH in the non‐PCOM group was 47 pmol/l, which was twofold lower than in the PCOM group but above the upper limit of normo‐ovulatory women.

Conclusions

According to a revised threshold of 25 follicles, almost half the anovulatory infertile women do not have PCOM. The characteristics of these women may be compatible with hypothalamic anovulation, but according to AMH levels, the ovaries remain multifollicular.

Perspectives

A better distinction between hypothalamic amenorrhoea and PCOS could improve treatment strategies for anovulatory infertility.
Novel 3D polycaprolactone scaffold for ridge preservation – a pilot randomised controlled clinical trial
Authors: Goh Bee Tin , Teh Luan Yook , Tan Danny Ben Poon , Zhang Zhiyong , Teoh Swee Hin
Published: September 2014

Objectives

This pilot randomised controlled clinical trial aimed to evaluate the feasibility and effectiveness of using a polycaprolactone (PCL) scaffold in fresh extraction sockets for ridge preservation. The hypothesis was that the insertion of a 3D bioresorbable PCL scaffold in fresh extraction sockets allowed for normal bone healing and better maintenance of ridge dimensions after 6 months as compared to extraction sockets without the scaffold.

Material and methods

Thirteen patients were randomised to either the test group (N = 6) where a PCL scaffold was inserted in the tooth socket after extraction or the control group (N = 7) where no space filler was used. Alveolar ridge height and width measurements were made at baseline and 6 months post‐extraction, for the evaluation of bone resorption. At 6 months, a core of bone was trephined out from the healed ridge for microcomputed tomographic (micro CT) and histological analyses, immediately before Stage I dental implant surgery. Stage II dental implant surgery was performed 4–6 months later.

Results

There was less vertical ridge resorption in the test group compared to the control group, and the difference was statistically significant in the mesio‐buccal aspect (P = 0.008). Micro CT and histological observations showed mainly mineralised bone formation in both groups, except for one specimen in the test group.

Conclusions

The insertion of a 3D bioresorbable PCL scaffold in fresh extraction sockets allowed for normal bone healing, and there was better maintenance of ridge height after 6 months as compared to extraction sockets without the scaffold.
Effects of different biomaterials on augmented bone volume resorptions
Authors: Ezirganli Seref , Kazancioglu Hakki O. , Mihmanli Ahmet , Sharifov Rasul , Aydin Mehmet S.
Published: September 2014

Objectives

The aim of this study was to assess the effects of platelet‐rich fibrin (PRF), deproteinized bovine bone graft (DBBG), and biphasic calcium phosphate (BCP) biomaterials on total volume resorption levels and bone augmentation.

Materials and methods

Nine New Zealand rabbits were divided into three groups (PRF,DBBG, andBCP). Two titanium barriers were fixed bilaterally to each rabbit's calvarium; a total of 18 titanium barriers were used. All barriers were removed on the 90th day. Computed tomography (CT) images of the animals were taken on the 90th, 120th, 150th, and 180th days.

Results

When the resorption level of the total volume in all groups on the 120th, 150th, and 180th days was compared with that of the 90th day, no significant differences among all groups were found in all intervals. According to the total volume on the 90th and 180th days, statistically significant differences between groupsDBBGandBCPwere not found; however, statistically significant differences were found between groupPRFand the others groups (P < 0.001). On the other hand, there were statistically significant differences in regenerated bone area between groupPRFandBCP.

Conclusion

According to the results of this study, grafts such asDBBGorBCPmust be used to augment bone volume sufficiently in guided bone regeneration.