bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Human Papillomavirus Detection by Aptima HPV and cobas HPV Tests in a Population of Women Referred for Colposcopy following Detection of Atypical Squamous Cells of Undetermined Significance by Pap Cytology
Authors: Castle Philip E. , Eaton Barbara , Reid Jennifer , Getman Damon , Dockter Janel
Published: February 2015

Few studies have compared the cobas HPV test to the Aptima HPV assay (AHPV) and the Aptima HPV 16 18/45 genotype assay (AHPV GT) for high-risk human papillomavirus (hrHPV) detection, clinical performance in detecting cervical intraepithelial neoplasia grade 2 (CIN2) or more severe (CIN2+) diagnoses, and risk stratification by partial HPV genotyping. The cobas HPV test is a DNA test that separately and concurrently detects HPV16, HPV18, and a pool of 12 other hrHPV types. AHPV is an RNA test for a pool of 14 hrHPV genotypes, and AHPV GT is an RNA test run on AHPV-positive results to detect HPV16 separately from HPV18 and HPV45, which are detected together. In a population of patients (
n
= 988) referred for colposcopy because of a cervical Pap cytology result of atypical squamous cells of undetermined significance (ASC-US), a cervical scrape specimen was taken, placed into a ThinPrep Pap test vial containing PreservCyt liquid cytology medium, and tested in a blinded fashion with cobas and AHPV and with AHPV GT for AHPV-positive results. The final diagnoses were based on a consensus panel review of the biopsy specimen histology. AHPV and cobas were equally sensitive for CIN2+ diagnoses (89.4% each;
P
= 1.000), and AHPV was more specific than cobas (63.1% versus 59.3%;
P
≤ 0.001). The percent total agreement, percent positive agreement, and kappa value were 90.9%, 81.1%, and 0.815, respectively. Risk stratification using partial HPV genotyping was similar for the two assays. AHPV and AHPV GT had similar sensitivity and risk stratification to cobas HPV, but they were more specific than cobas HPV.
Glycosylation of Mouse DPP4 Plays a Role in Inhibiting Middle East Respiratory Syndrome Coronavirus Infection
Authors: Peck Kayla M. , Cockrell Adam S. , Yount Boyd L. , Scobey Trevor , Baric Ralph S. , Heise Mark T.
Published: February 2015

Middle East respiratory syndrome coronavirus (MERS-CoV) utilizes dipeptidyl peptidase 4 (DPP4) as an entry receptor. Mouse DPP4 (mDPP4) does not support MERS-CoV entry; however, changes at positions 288 and 330 can confer permissivity. Position 330 changes the charge and glycosylation state of mDPP4. We show that glycosylation is a major factor impacting DPP4 receptor function. These results provide insight into DPP4 species-specific differences impacting MERS-CoV host range and may inform MERS-CoV mouse model development.
Expression of Human Decay-Accelerating Factor on Intestinal Epithelium of Transgenic Mice Does Not Facilitate Infection by the Enteral Route
Authors: Pan Jieyan , Zhang Lili , Odenwald Matthew A. , Shen Le , Turner Jerrold R. , Bergelson Jeffrey M.
Published: February 2015

In vitro
, infection of polarized human intestinal epithelial cells by coxsackievirus B3 (CVB3) depends on virus interaction with decay-accelerating factor (DAF), a receptor expressed on the apical cell surface. Although mice are highly susceptible to CVB3 infection when virus is delivered by intraperitoneal injection, infection by the enteral route is very inefficient. Murine DAF, unlike human DAF, does not bind virus, and we hypothesized that the absence of an accessible receptor on the intestinal surface is an important barrier to infection by the oral route. We generated transgenic mice that express human DAF specifically on intestinal epithelium and measured their susceptibility to infection by a DAF-binding CVB3 isolate. Human DAF permitted CVB3 to bind to the intestinal surface
ex vivo
and to infect polarized monolayers of small-intestinal epithelial cells derived from DAF transgenic mice. However, expression of human DAF did not facilitate infection by the enteral route either in immunocompetent animals or in animals deficient in the interferon alpha/beta receptor. These results indicate that the absence of an apical receptor on intestinal epithelium is not the major barrier to infection of mice by the oral route.

IMPORTANCE
CVB3 infection of human intestinal epithelial cells depends on DAF at the apical cell surface, and expression of human DAF on murine intestinal epithelial cells permits their infection
in vitro
. However, expression of human DAF on the intestinal surface of transgenic mice did not facilitate infection by the oral route. Although the role of intestinal DAF in human infection has not been directly examined, these results suggest that DAF is not the critical factor in mice.
African Green Monkey TRIM5α Restriction in Simian Immunodeficiency Virus-Specific Rhesus Macaque Effector CD4 T Cells Enhances Their Survival and Antiviral Function
Authors: Jain Sumiti , Trivett Matthew T. , Ayala Victor I. , Ohlen Claes , Ott David E.
Published: February 2015

The expression of xenogeneic TRIM5α proteins can restrict infection in various retrovirus/host cell pairings. Previously, we have shown that African green monkey TRIM5α (AgmTRIM5α) potently restricts both human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus mac239 (SIV
mac239
) replication in a transformed human T-cell line (L. V. Coren, et al., Retrovirology 12:11, 2015,
http://dx.doi.org/10.1186/s12977-015-0137-9
). To assess AgmTRIM5α restriction in primary cells, we transduced AgmTRIM5α into primary rhesus macaque CD4 T cells and infected them with SIV
mac239
. Experiments with T-cell clones revealed that AgmTRIM5α could reproducibly restrict SIV
mac239
replication, and that this restriction synergizes with an intrinsic resistance to infection present in some CD4 T-cell clones. AgmTRIM5α transduction of virus-specific CD4 T-cell clones increased and prolonged their ability to suppress SIV spread in CD4 target cells. This increased antiviral function was strongly linked to decreased viral replication in the AgmTRIM5α-expressing effectors, consistent with restriction preventing the virus-induced cytopathogenicity that disables effector function. Taken together, our data show that AgmTRIM5α restriction, although not absolute, reduces SIV replication in primary rhesus CD4 T cells which, in turn, increases their antiviral function. These results support prior
in vivo
data indicating that the contribution of virus-specific CD4 T-cell effectors to viral control is limited due to infection.

IMPORTANCE
The potential of effector CD4 T cells to immunologically modulate SIV/HIV infection likely is limited by their susceptibility to infection and subsequent inactivation or elimination. Here, we show that AgmTRIM5α expression inhibits SIV spread in primary effector CD4 T cells
in vitro
. Importantly, protection of effector CD4 T cells by AgmTRIM5α markedly enhanced their antiviral function by delaying SIV infection, thereby extending their viability despite the presence of virus. Our
in vitro
data support prior
in vivo
HIV-1 studies suggesting that the antiviral CD4 effector response is impaired due to infection and subsequent cytopathogenicity. The ability of AgmTRIM5α expression to restrict SIV infection in primary rhesus effector CD4 T cells now opens an opportunity to use the SIV/rhesus macaque model to further elucidate the potential and scope of anti-AIDS virus effector CD4 T-cell function.
Chimeric Rhinoviruses Obtained via Genetic Engineering or Artificially Induced Recombination Are Viable Only if the Polyprotein Coding Sequence Derives from the Same Species
Authors: Schibler Manuel , Piuz Isabelle , Hao Weidong , Tapparel Caroline
Published: February 2015

Recombination is a widespread phenomenon that ensures both the stability and variation of RNA viruses. This phenomenon occurs with different frequencies within species of the
Enterovirus
genus. Intraspecies recombination is described frequently among non-rhinovirus enteroviruses but appears to be sporadic in rhinoviruses. Interspecies recombination is even rarer for rhinoviruses and mostly is related to ancient events which contributed to the speciation of these viruses. We reported that artificially engineered 5′ untranslated region (UTR) interspecies rhinovirus/rhinovirus or rhinovirus/non-rhinovirus enterovirus recombinants are fully viable. Using a similar approach, we demonstrated in this study that exchanges of the P1-2A polyprotein region between members of the same rhinovirus species, but not between members of different species, give rise to competent chimeras. To further assess the rhinovirus intra- and interspecies recombination potential, we used artificially induced recombination by cotransfection of 5′-end-deleted and 3′-end-deleted and replication-deficient genomes. In this system, intraspecies recombination also resulted in viable viruses with high frequency, whereas no interspecies rhinovirus recombinants could be recovered. Mapping intraspecies recombination sites within the polyprotein highlighted recombinant hotspots in nonstructural genes and at gene boundaries. Notably, all recombinants occurring at gene junctions presented in-frame sequence duplications, whereas most intragenic recombinants were homologous. Taken together, our results suggest that only intraspecies recombination gives rise to viable rhinovirus chimeras in the polyprotein coding region and that recombination hotspots map to nonstructural genes with in-frame duplications at gene boundaries. These data provide new insights regarding the mechanism and limitations of rhinovirus recombination.

IMPORTANCE
Recombination represents a means to ensure both the stability and the variation of RNA viruses. While intraspecies recombination is described frequently among non-rhinovirus enteroviruses, it seems to occur more rarely in rhinoviruses. Interspecies recombination is even rarer in this virus group and is mostly related to ancient events, which contributed to its speciation. We used engineered chimeric genomes and artificially induced RNA recombination to study experimentally the recombination potential of rhinoviruses and analyze recombination sites. Our results suggest that only intraspecies recombination gives rise to viable chimeras in the polyprotein coding region. Furthermore, characterization of intraspecies chimeras provides new insight into putative recombination hotspots within the polyprotein. In summary, we applied two powerful and complementary experimental approaches to improve current knowledge on rhinovirus recombination.
Niemann-Pick type B in adulthood
Authors: Simões Rita Gonçalves , Maia Helena
Published: February 2015

Niemann-Pick disease (NPD) is a rare group of autosomal recessive disorders associated with intracellular deposition of sphingomyelin. NPD type B is a milder form, generally later in onset, with a good prognosis for survival into adulthood and usually with no neurological abnormalities. The authors describe the case of a 52-year-old man who presented with unexplained pancytopenia and splenomegaly. He was admitted to emergency splenectomy due to pathological splenic rupture. The histological findings showed diffuse histiocytosis, suggesting lysosomal storage disease. The NPD was confirmed when residual activity of acid sphingomyelinase in peripheral blood leucocytes and cultured skin fibroblasts was detected. Besides lipid abnormalities, the patient also had lipid interstitial pneumonia. There is no treatment for NPD. Management is based on surveillance and supportive care. The patient has reached the sixth decade of life with no symptoms and, despite the pneumonia and splenectomy, he still has a fairly healthy life.
Prolonged duration of transbrachial intra-aortic balloon pump as bridge to heart transplantation
Authors: Smith Triston B B J , Shridhar Puneeth , Khalil Ramzi , Lasorda David Michael
Published: February 2015

We describe a case demonstrating the quality of life (QOL) benefit and safety of using a transbrachial approach for insertion of an intra-aortic balloon pump (IABP) in a patient awaiting cardiac transplantation. A 68-year-old man with ischaemic cardiomyopathy was admitted to our cardiac intensive care unit to await the availability of a suitable donor organ for orthotopic heart transplant. An IABP was needed for haemodynamic support due to cardiogenic shock. Since the patient did not want to be committed to lying supine in bed for multiple days, as would have been the case had the IABP been placed using the conventional femoral route, we inserted a 7.5 Fr ‘sheathless’ IABP via the transbrachial approach. The patient's haemodynamics improved and the device was left in place for 240 h without vascular compromise. He was subsequently successfully transplanted and is doing well on follow-up.
Service evaluation of the GOALS family-based childhood obesity treatment intervention during the first 3 years of implementation
Authors: Watson Paula M , Dugdill Lindsey , Pickering Katie , Owen Stephanie , Hargreaves Jackie , Staniford Leanne J , Murphy Rebecca C , Knowles Zoe , Cable N Timothy
Published: February 2015

Objectives

To evaluate the impact of the GOALS (Getting Our Active Lifestyles Started) family-based childhood obesity treatment intervention during the first 3 years of implementation.

Design

Single-group repeated measures with qualitative questionnaires.

Setting

Community venues in a socioeconomically deprived, urban location in the North-West of England.

Participants

70 overweight or obese children (mean age 10.5 years, 46% boys) and their parents/carers who completed GOALS between September 2006 and March 2009.

Interventions

GOALS was a childhood obesity treatment intervention that drew on social cognitive theory to promote whole family lifestyle change. Sessions covered physical activity (PA), diet and behaviour change over 18 2 h weekly group sessions (lasting approximately 6 months). A Template for Intervention Description and Replication (TIDieR) checklist of intervention components is provided.

Primary and secondary outcome measures

The primary outcome measure was child body mass index (BMI) z-score, collected at baseline, post-intervention and 12 months. Secondary outcome measures were child self-perceptions, parent/carer BMI and qualitative changes in family diet and PA (parent/carer questionnaire).

Results

Child BMI z-score reduced by 0.07 from baseline to post-intervention (p<0.001) and was maintained at 12 months (p<0.05). There was no change in parent/carer BMI or child self-perceptions, other than an increase in perceived social acceptance from baseline to post-intervention (p<0.05). Parents/carers reported positive changes to family PA and dietary behaviours after completing GOALS.

Conclusions

GOALS completion was associated with small improvements in child BMI z-score and improved family PA and dietary behaviours. Several intervention modifications were necessary during the implementation period and it is suggested childhood obesity treatment interventions need time to embed before a definitive evaluation is conducted. Researchers are urged to use the TIDieR checklist to ensure transparent reporting of interventions and facilitate the translation of evidence to practice.
Trauma airway management in emergency departments: a multicentre, prospective, observational study in Japan
Authors: Nakao Shunichiro , Kimura Akio , Hagiwara Yusuke , Hasegawa Kohei
Published: February 2015

Objectives

Although successful airway management is essential for emergency trauma care, comprehensive studies are limited. We sought to characterise current trauma care practice of airway management in the emergency departments (EDs) in Japan.

Design

Analysis of data from a prospective, observational, multicentre registry—the Japanese Emergency Airway Network (JEAN) registry.

Setting

13 academic and community EDs from different geographic regions across Japan.

Participants

723 trauma patients who underwent emergency intubation from March 2010 through August 2012.

Outcome measures

ED characteristics, patient and operator demographics, methods of airway management, intubation success or failure at each attempt and adverse events.

Results

A total of 723 trauma patients who underwent emergency intubation were eligible for the analysis. Traumatic cardiac arrest comprised 32.6% (95% CI 29.3% to 36.1%) of patients. Rapid sequence intubation (RSI) was the initial method chosen in 23.9% (95% CI 21.0% to 27.2%) of all trauma patients and in 35.5% (95% CI 31.4% to 39.9%) of patients without cardiac arrest. Overall, intubation was successful in ≤3 attempts in 96% of patients (95% CI 94.3% to 97.2%). There was a wide variation in the initial methods of intubation; RSI as the initial method was performed in 0–50.9% of all trauma patients among 12 EDs. Similarly, there was a wide variation in success rates and adverse event rates across the EDs. Success rates varied between 35.5% and 90.5% at the first attempt, and 85.1% and 100% within three attempts across the 12 EDs.

Conclusions

In this multicentre prospective study in Japan, we observed a high overall success rate in airway management during trauma care. However, the methods of intubation and success rates were highly variable among hospitals.
Radiography of the equine stifle
Authors: Hennessy Simon , Singer Ellen
Published: February 2015

The stifle is a complex joint and, when faced with a patient suffering from pain in this area, a veterinary surgeon will often use radiography as the first port of call. This article describes the radiographic projections routinely acquired of the stifle region, and the common conditions diagnosed with this imaging modality, while acknowledging that additional imaging modalities are often required to reach a final diagnosis.
Republished: The first North American use of the Pipeline Flex flow diverter
Authors: Duckworth Edward AM , Nickele Christopher , Hoit Daniel , Belayev Andrey , Moran Christopher J , Arthur Adam S
Published: February 2015

Flow diversion for the management of intracranial aneurysms represents a paradigm shift in how aneurysms are managed. The Pipeline embolization device (PED) is, to date, the only flow diverter approved for use in the USA by the Food and Drug Administration. Limitations and complications with new treatment strategies are inevitable, and with the PED there have been reports of complications, most commonly with challenging deployments. Once deployment has been initiated, the device is ‘one-way’; it can only be deployed further or removed. Yet, situations arise in which the ability to recapture or reposition the device would be advantageous. A second-generation Pipeline has been developed that addresses these concerns. We report the first use in North America of this second-generation Pipeline device: the Pipeline Flex. We discuss our rationale for using the device, our impressions of its operation, and the relevant literature concerning the current state of flow diversion.
Republished: Emergency placement of stent-graft for symptomatic acute carotid artery occlusion after endarterectomy
Authors: Ko Jun Kyeung , Choi Chang Hwa , Lee Sang Weon , Lee Tae Hong
Published: February 2015

A patient underwent a left-sided carotid endarterectomy (CEA) for an asymptomatic 80% carotid artery (CA) stenosis. There were no signs of intolerance during the carotid cross-clamping and an initially uneventful awakening was observed. However, in the third postoperative hour he experienced left amaurosis and dysarthria. An urgent MRI showed an occluded internal CA on the operated site without evidence of acute infarction. To recanalize the occluded internal CA and minimize leakage from the arteriotomy site, a self-expandable stent-graft was placed, covering the dissection and the distal atherosclerotic lesions. Complete recanalization of the left internal CA was achieved and the patient showed a dramatic improvement of his preoperative deficits. To our knowledge, this is the first case of stent-graft implantation for a symptomatic acute CA occlusion following CEA. Stent-graft placement should be considered as an alternative method of treatment for acute CA occlusion or dissection following CEA.
Type 2 diabetes in youth
Authors: Cameron Erin , O’Reilly Caitlin
Published: February 2015

Since the 1990s, concerns about a global obesity epidemic have flourished. These concerns regarding obesity are expressed in popular culture and scientific literature and emphasize both weight and weight loss when defining health and well-being. As a result scholars are now calling attention to a “shadow epidemic” of weight stigma that is shown to have harmful physiological and psychological impacts in youth. In tandem with “globesity” concerns, there has been a similar concern expressed over the epidemic of type 2 diabetes, which some have termed “diabesity.” Although there is less known about diabetes stigma, the topic has much overlap with obesity stigma. In this narrative review we discuss the related problems of obesity and type 2 diabetes stigma, with an emphasis on issues specific to youth, as relevant. Drawing from literature on weight bias, critical weight studies, and Health at Every Size (HAES), we highlight pedagogical approaches to address obesity stigma and their implications to redress the problem of type 2 diabetes-related stigma in health care.
Children have type 2 diabetes too: an historical perspective
Authors: Dean Heather J. , Sellers Elizabeth A.C.
Published: February 2015

Prior to 1985, type 2 diabetes was a disease of adults. Simultaneously with the global epidemic of childhood obesity, type 2 diabetes has increased in children. Initially, the presentation of small case series of type 2 diabetes in children was met with skepticism. As the number and size of the case series grew and the first long-term outcomes of end-stage complications in young adults appeared in the literature, the international community took notice with guarded interest. Type 2 diabetes disproportionately affects the children of specific ethnic groups and from disadvantaged socioeconomic environments, especially Indigenous populations. The past decade has seen unprecedented intense global interest in the etiology, treatment, and prevention of type 2 diabetes in children.
Effect of nonextensive electrons on dust–ion acoustic wave self-modulation
Authors: Panahi N. , Alinejad H. , Mahdavi M.
Published: February 2015

Nonlinear self-modulation of dust–ion acoustic (DIA) waves is studied in an unmagnetized dusty plasma comprising warm adiabatic ions, arbitrarily charged dust particles, and hot nonextensive q-distributed electrons. By employing the multiple space and time scales perturbation, a nonlinear Schrödinger equation is derived for the evolution of the wave amplitude. The existence along with the stability of wave packets are discussed in the parameter space of two oppositely charged dust and ion temperature over different ranges of the nonextensive parameter q. The growth rate of the modulation instability is also given for different values of the q parameter. It is found that the critical wave number at which the instability sets in increases as the nonextensive parameter q increases. This leads to a wider range (in spatial extension) of the stable envelope solitons. It is also found that the effects of ion temperature and negative (positive) dust concentration significantly modify the criteria for the modulation instability of DIA waves. Our finding should elucidate the nonlinear electrostatic structures that propagate in astrophysical and cosmological plasma scenarios where nonextensive particles exist: such as instellar plasma, stellar polytropes, cosmic radiation, and systems with long-rang interaction.
Quasi-static thermal evolution of compact objects
Authors: Becerra L. , Hernández H. , Núñez L.A.
Published: February 2015

We study under what conditions the thermal peeling is present for dissipative local and quasi-local anisotropic spherical matter configurations. Thermal peeling occurs when different signs in the velocity of fluid elements appear, giving rise to the splitting of the matter configuration. The evolution is considered in the quasi-static approximation and the matter contents are radiant, anisotropic (unequal stresses) spherical local, and quasi-local fluids. The heat flux and the associated temperature profiles are described by causal thermodynamics consistent with this approximation. It is found that both types of configurations can exhibit thermal peeling when most of the radiated energy emerges from the first half of the distribution, and thermal peeling appears to be associated with extreme astrophysical scenarios (highly relativistic and very energetic gravitational system).
Nonlinear dynamic image-based visual servoing of a quadrotor
Authors: Fink Geoff , Xie Hui , Lynch Alan F. , Jagersand Martin
Published: February 2015

This paper proposes a dynamic image-based visual servoing (IBVS) control law for a quadrotor unmanned aerial vehicle (UAV) equipped with a single fixed on-board camera facing downward. The motion control problem is to regulate the relative lateral position of the vehicle to a stationary target located on the ground. The control law is termed dynamic as it is based on the dynamics and kinematics of the vehicle. The proposed design uses a nonlinear input-dependent change of state coordinates and its error dynamics are proven to be locally exponentially stable with an estimate provided for the region of attraction. Experimental and simulation results demonstrate the method's ease of on-board implementation, performance, and robustness. The simulation and experimental results include a comparison with an established dynamic IBVS method. This comparison shows the proposed method can provide similar performance with the benefit of reduced complexity.
Averaging problems of running processes associated with Brownian motion and applications
Authors: Ta Bao Quoc
Published: February 2015

Recently the new technique to solve optimal stopping problems for Hunt processes is developed (see [S. Christensen, P. Salminen and B. Q. Ta, Optimal stopping of strong Markov processes, Stochastic Process. Appl. 123(3) (2013) 1138–1159]). The crucial feature of the approach is to utilize the representation of the r-excessive functions as expected suprema. However, it seems to be difficult when applying directly the approach to some concrete cases, e.g. one-sided problem for reflecting Brownian motion and two-sided problem for Brownian motion. In this paper, we review and exploit this approach to find explicit solutions of two problems above.
Observability of triple or double charged Higgs production in two Higgs doublet model type II at an e+e- linear collider
Authors: Hashemi M. , Ahmed I.
Published: February 2015

In this paper the charged Higgs signal through triple or double Higgs production in a two Higgs doublet model (2HDM) type II is studied. The main production process is e+e- →H+H-H0 followed by the charged Higgs decay to a pair of τν and the neutral Higgs decay to [Formula: see text]. The alternative process H+W-H0 is also included as a source of charged Higgs signal in the analysis. The focus is on a future e+e- linear collider operating at [Formula: see text]. The final state under consideration [Formula: see text] is suitable for electroweak background rejection using the b-tagging tools. It is shown that although the signal cross-section is small, with a reasonable background suppression, high signal significance values are achievable at an integrated luminosity 500 fb-1 depending on the charged Higgs mass, tan β and the CP-odd neutral Higgs mass. Finally results are quoted in terms of the signal significance for charged Higgs in the mass range 160 < mH± < 400 GeV .
Ru2Ti1-xFexGe: Novel candidate for the spintronic applications
Authors: Hamri A. , Dridi Z. , Hamri B. , Hallouche A.
Published: February 2015

The mechanical, electronic and magnetic properties of the full heusler alloys Ru 2 Ti 1-x Fe x Ge for the concentrations x = 0, 0.25, 0.5, 0.75, 1 using WIEN2k implementation of full potential linearized augmented plane wave (FP-LAPW) method in order to find a new compound for the spintronic applications within generalized gradient approximation (GGA) and modified Becke Johnson exchange potential with generalized gradient approximation (MBJ-GGA) as exchange correlation (XC) potential are reported for the first time. Our results show that the Fe incorporating in the Ru 2 TiGe created a half metallic (HM) gap at Fermi level (EF) in minority spin channel (MIC) and induced a magnetic moment on the paramagnetic Ru 2 TiGe . Moreover, the HM gap decreases with increasing the concentrations from 0.25 to 0.75, while the magnetic moment undergoes an inverse behavior.
Odd–even effect of melting finite polymer film on square lattice
Authors: Si Tieyan
Published: February 2015

Two-dimensional film system bears many exotic thermodynamics behaviors. We proposed a mathematical physics model to explore how the melting temperature of a two-dimensional mathematical dimer film depends on the odd–evenness of the finite width of dimer film. A weak external bond between dimers is introduced into the classical dimer model in this dimer film. We derived a general equation of melting temperature and applied it for computing the melting temperature of a dimer film covering a finite square lattice. The melting temperature is proportional to the external bonding energy that we assume it binds neighboring dimers together and proportional to the inverse of entropy per site. Furthermore, it shows fusing two small rectangular dimer film with odd number of length into one big rectangular film gains more entropy than fusing two small rectangles with even number of length into the same big rectangle. Fusing two small toruses with even number of length into one big torus reduces entropy. Fusing two small toruses with odd number of length increases the entropy. Thus two dimer films with even number of length repel each other, two dimer films with odd length attract each other. The odd–even effect is also reflected on the correlation function of two topologically distinguishable loops in a torus surface. The entropy of finite system dominates odd–even effect. This model has straightforward extension to longer polymers and three-dimensional systems.
Possibilistic Intuitionistic Fuzzy c-Means Clustering Algorithm for MRI Brain Image Segmentation
Authors: Verma Hanuman , Agrawal R. K.
Published: February 2015

Accurate segmentation of human brain image is an essential step for clinical study of magnetic resonance imaging (MRI) images. However, vagueness and other ambiguity present between the brain tissues boundaries can lead to improper segmentation. Possibilistic fuzzy c-means (PFCM) algorithm is the hybridization of fuzzy c-means (FCM) and possibilistic c-means (PCM) algorithms which overcomes the problem of noise in the FCM algorithm and coincident clusters problem in the PCM algorithm. A major challenge posed in the PFCM algorithm for segmentation of ill-defined MRI image with noise is to take into account the ambiguity in the final localization of the feature vectors due to lack of qualitative information. This may lead to improper assignment of membership (typicality) value to their desired cluster. In this paper, we have proposed the possibilistic intuitionistic fuzzy c-means (PIFCM) algorithm for Atanassov’s intuitionistic fuzzy sets (A-IFS) which includes the advantages of the PCM, FCM algorithms and A-IFS. Real and simulated MRI brain images are segmented to show the superiority of the proposed PIFCM algorithm. The experimental results demonstrate that the proposed algorithm yields better result.
THERMAL OXIDATION OF Ti6Al4V ALLOY WITH ENHANCED WEAR AND CORROSION RESISTANCE FOR OIL AND GAS APPLICATION: EFFECT OF TEMPERATURE
Authors: LIN NAIMING , ZHOU PENG , WANG YATING , ZOU JIAOJUAN , MA YONG , WANG ZHENXIA , TIAN WEI , YAO XIAOFEI , TANG BIN
Published: February 2015

Thermal oxidation (TO) treatments were performed at 873 K, 898 K, 923 K, 948 K, 973 K, 998 K and 1023 K for 10 h in air to improve the wear and corrosion resistance of Ti 6 Al 4 V alloy. The effect of TO temperature on microstructural characterizations and surface properties of the obtained TO layers were investigated. The results showed that TO layers with various thickness values were formed on Ti 6 Al 4 V alloy under different temperatures. The thickness of the TO layers increased with the increasing of TO temperature. TO layer that was obtained at 973 K suggested the highest surface hardness and the best wear resistance. TO layer that was realized at 948 K exhibited superior corrosion resistance to other TO layers. TO treatment could be considered as an effective method for preventing wear and corrosion of Ti 6 Al 4 V alloy.
ELECTRICITY FUTURES PRICE MODELING WITH LÉVY TERM STRUCTURE MODELS
Authors: BIAGINI FRANCESCA , BREGMAN JULIA , MEYER-BRANDIS THILO
Published: February 2015

In this paper, we generalize the approach of Hinz & Wilhelm (2006), Pricing flow commodity derivatives using fixed income market techniques. International Journal of Theoretical and Applied Finance 9, 1299–1321, replacing in the dynamics of the asset prices the Brownian motion by a more general Lévy process, also taking into account the occurrence of spikes. In particular, we reduce the modeling of an electricity futures market to the modeling of a Lévy bond market with an additional risky asset. This allows to employ well established techniques from interest rate term structure modeling. We then examine Markovianity of the induced electricity spot price, an important property when it comes to option pricing. We show that the considered method combined with the Fourier transform techniques provides semi analytic pricing formulas for European electricity options. Finally, we consider the pricing of path dependent derivatives such as electricity swing options.
Large Displacement Analysis of Rectangular Orthotropic Membranes Under Stochastic Impact Loading
Authors: Zheng Zhou-Lian , Lu Fa-Ming , He Xiao-Ting , Sun Jun-Yi , Xie Chuan-Xi , He Chao
Published: February 2015

This paper studies the calculation method about the displacement response mean function of rectangular orthotropic membranes with four edges fixed under stochastic impact loading. We set up the nonlinear stochastic governing differential equation, solve it according to the perturbation method and the random vibration theory and obtain the displacement response mean value function of the membrane surface. Furthermore, this paper makes a random simulation test for ZZF membrane material which is commonly applied in the membrane structural engineering and obtains abundant deflection response sample curves about the feature points of the membrane surface. For sample curves statistical analysis at some fixed time, sample means can be obtained, which verify the correctness of the theoretical calculation method. The calculation method provides a theoretical basis for vibration control of building membrane structures to control the occurrence of natural disasters.
Entangled states implemented by Bngroup operators, including properties based on HS decompositions, separability and concurrence
Authors: Ben-Aryeh Y.
Published: February 2015

The use of the Bngroup operators is developed for implementing entangling processes for large n-qubits systems (n > 2). By operating with the Bngroup operators on the computational basis of states, entangled states are obtained with properties analogous to those of the 2-qubits Bell states. Tracing any qubit from the 3-qubits Bnentangled states, we get mixed states which are separable with zero concurrence, and correspondingly with only classical correlations. These properties are generalized to larger Bnentangled states (n > 3). The properties of the Bnentangled states are analyzed by the use of Hilbert–Schmidt (HS) decompositions.
Controlling entanglement of two qubits by quantum-jump-based feedback beyond rotating-wave approximation
Authors: Yang Qing , Liu Hui , Zhen Xiu-Lan , Yang Ming , Cao Zhuo-Liang
Published: February 2015

The entanglement dynamics of two identical atoms coupled to a single-mode cavity is considered. Based on the reduced non-perturbative quantum master equation method, the entanglement evolution of the two atoms with spontaneous emission under the quantum-jump-based feedback control is investigated beyond the conventional rotating-wave approximation (RWA). The research of entanglement evolution beyond RWA is a significant problem because of its importance to the field of strong coupling. The result of numerical simulations shows that an appropriate feedback control can prolong the entanglement time and increase the entanglement amplitude. The effect of synchronous control on two atoms is superior to that of one control.
New Minkowski type inequalities and entropic inequalities for quantum states of qudits
Authors: Man'ko V. I. , Markovich L. A.
Published: February 2015

The two-parameter Minkowski like inequality written for composite quantum system state is obtained for arbitrary Hermitian non-negative matrix with trace equal to unity. The inequality can be used as entropic and information inequality for density matrix of noncomposite finite quantum system, e.g. for a single qudit state. The analogs of strong subadditivity condition for the single qudit is discussed in context of obtained Minkowski like inequality.
Generation of optical-terahertz biphoton pairs via spontaneous parametric down-conversion
Authors: Kornienko V. V. , Germanskiy S. A. , Kitaeva G. Kh. , Penin A. N.
Published: February 2015

We examine the features of parametric down-conversion for generating non-classical optical-terahertz biphoton fields. The calculations were performed for a second-order correlation function and noise reduction factor (NRF), which were selected as measures of non-classicality of the field states. NRF measurement schemes were found to be less advantageous. Overall system temperature at which non-classical effects are still observable has been estimated as about 10 K. The priority of the main complicating factors for the quantum-optical measurements in the terahertz range has been determined. Thus, the most important parameter is the temperature of the system, after that come the absorption losses at terahertz frequencies, and the parametric conversion efficiency has the lowest impact. Increasing the pump radiation power has been found to be inefficient for "noise" suppression in this case. The calculations performed were based on lithium niobate dispersion properties due to its outstanding nonlinear optical properties and because it is frequently used for optical-to-terahertz frequency conversion.
Heat transfer analysis of bi-viscous ciliary motion fluid
Authors: Sher Akbar Noreen , Khan Z. H.
Published: February 2015

The impulsion system of cilia motion is deliberated by biviscosity fluid model. The problem of two-dimensional motion of biviscosity fluid privileged in a symmetric channel with ciliated walls is considered. The features of ciliary structures are resolute by the supremacy of viscous effects above inertial possessions by the long-wavelength and low Reynolds approximation. Closed-form solutions for the longitudinal pressure gradient, temperature and velocities are obtained. The pressure gradient and volume flow rate for different values of the biviscosity are also premeditated. The flow possessions for the biviscosity fluid resolute as a function of the cilia and metachronal wave velocity.
Generalized Hamiltonian for a graphene subjected to arbitrary in-plane strains
Authors: Wang Biao , Wang Yunhua , Liu Yulan
Published: February 2015

The interplay between the linear elastic deformation up to 20% and the unique electronic properties of graphene nanostructures offers an attractive prospect to manipulate their properties by strain. Here we review the recent progress on the electronic response of graphene to the in-plane strains, including the strain-modulated electronic structure and the strain-modulated spin, valley and superconducting transports. A generalized Hamiltonian for a graphene was constructed subjected to arbitrary in-plane strains. The Hamiltonian is helpful to design and optimize the graphene-based nano-electromechanical systems (NEMS).
Fluid shear, intercellular stress, and endothelial cell alignment
Authors: Steward Robert , Tambe Dhananjay , Hardin C. Corey , Krishnan Ramaswamy , Fredberg Jeffrey J.
Published: February 2015

Endothelial cell alignment along the direction of laminar fluid flow is widely understood to be a defining morphological feature of vascular homeostasis. While the role of associated signaling and structural events have been well studied, associated intercellular stresses under laminar fluid shear have remained ill-defined and the role of these stresses in the alignment process has remained obscure. To fill this gap, we report here the tractions as well as the complete in-plane intercellular stress fields measured within the human umbilical vein endothelial cell (HUVEC) monolayer subjected to a steady laminar fluid shear of 1 Pa. Tractions, intercellular stresses, as well as their time course, heterogeneity, and anisotropy, were measured using monolayer traction microscopy and monolayer stress microscopy. Prior to application of laminar fluid flow, intercellular stresses were largely tensile but fluctuated dramatically in space and in time (317 ± 122 Pa). Within 12 h of the onset of laminar fluid flow, the intercellular stresses decreased substantially but continued to fluctuate dramatically (142 ± 84 Pa). Moreover, tractions and intercellular stresses aligned strongly and promptly (within 1 h) along the direction of fluid flow, whereas the endothelial cell body aligned less strongly and substantially more slowly (12 h). Taken together, these results reveal that steady laminar fluid flow induces prompt reduction in magnitude and alignment of tractions and intercellular stress tensor components followed by the retarded elongation and alignment of the endothelial cell body. Appreciably smaller intercellular stresses supported by cell-cell junctions logically favor smaller incidence of gap formation and thus improved barrier integrity.
Distinct EEG seizure patterns reflect different seizure generation mechanisms
Authors: Salami Pariya , Lévesque Maxime , Gotman Jean , Avoli Massimo
Published: February 2015

Low-voltage fast (LVF)- and hypersynchronous (HYP)-seizure onset patterns can be recognized in the EEG of epileptic animals and patients with temporal lobe epilepsy. Ripples (80–200 Hz) and fast ripples (250–500 Hz) have been linked to each pattern, with ripples predominating during LVF seizures and fast ripples predominating during HYP seizures in the rat pilocarpine model. This evidence led us to hypothesize that these two seizure-onset patterns reflect the contribution of neural networks with distinct transmitter signaling characteristics. Here, we tested this hypothesis by analyzing the seizure activity induced with the K+ channel blocker 4-aminopyridine (4AP, 4–5 mg/kg ip), which enhances both glutamatergic and GABAergic transmission, or the GABAA receptor antagonist picrotoxin (3–5 mg/kg ip); rats were implanted with electrodes in the hippocampus, the entorhinal cortex, and the subiculum. We found that LVF onset occurred in 82% of 4AP-induced seizures whereas seizures after picrotoxin were always HYP. In addition, high-frequency oscillation analysis revealed that 4AP-induced LVF seizures were associated with higher ripple rates compared with fast ripples ( P < 0.05), whereas picrotoxin-induced seizures contained higher rates of fast ripples compared with ripples ( P < 0.05). These results support the hypothesis that two distinct patterns of seizure onset result from different pathophysiological mechanisms.
Vestibular implantation and longitudinal electrical stimulation of the semicircular canal afferents in human subjects
Authors: Phillips James O. , Ling Leo , Nie Kaibao , Jameyson Elyse , Phillips Christopher M. , Nowack Amy L. , Golub Justin S. , Rubinstein Jay T.
Published: February 2015

Animal experiments and limited data in humans suggest that electrical stimulation of the vestibular end organs could be used to treat loss of vestibular function. In this paper we demonstrate that canal-specific two-dimensionally (2D) measured eye velocities are elicited from intermittent brief 2 s biphasic pulse electrical stimulation in four human subjects implanted with a vestibular prosthesis. The 2D measured direction of the slow phase eye movements changed with the canal stimulated. Increasing pulse current over a 0–400 μA range typically produced a monotonic increase in slow phase eye velocity. The responses decremented or in some cases fluctuated over time in most implanted canals but could be partially restored by changing the return path of the stimulation current. Implantation of the device in Meniere's patients produced hearing and vestibular loss in the implanted ear. Electrical stimulation was well tolerated, producing no sensation of pain, nausea, or auditory percept with stimulation that elicited robust eye movements. There were changes in slow phase eye velocity with current and over time, and changes in electrically evoked compound action potentials produced by stimulation and recorded with the implanted device. Perceived rotation in subjects was consistent with the slow phase eye movements in direction and scaled with stimulation current in magnitude. These results suggest that electrical stimulation of the vestibular end organ in human subjects provided controlled vestibular inputs over time, but in Meniere's patients this apparently came at the cost of hearing and vestibular function in the implanted ear.
Expression and function of a CP339,818-sensitive K+current in a subpopulation of putative nociceptive neurons from adult mouse trigeminal ganglia
Authors: Sforna Luigi , D'Adamo Maria Cristina , Servettini Ilenio , Guglielmi Luca , Pessia Mauro , Franciolini Fabio , Catacuzzeno Luigi
Published: February 2015

Trigeminal ganglion (TG) neurons are functionally and morphologically heterogeneous, and the molecular basis of this heterogeneity is still not fully understood. Here we describe experiments showing that a subpopulation of neurons expresses a delayed-rectifying K+current ( IDRK) with a characteristically high (nanomolar) sensitivity to the dihydroquinoline CP339,818 (CP). Although submicromolar CP has previously been shown to selectively block Kv1.3 and Kv1.4 channels, the CP-sensitive IDRKfound in TG neurons could not be associated with either of these two K+channels. It could neither be associated with Kv2.1 channels homomeric or heteromerically associated with the Kv9.2, Kv9.3, or Kv6.4 subunits, whose block by CP, tested using two-electrode voltage-clamp recordings from Xenopus oocytes, resulted in the low micromolar range, nor to the Kv7 subfamily, given the lack of blocking efficacy of 3 μM XE991. Within the group of multiple-firing neurons considered in this study, the CP-sensitive IDRKwas preferentially expressed in a subpopulation showing several nociceptive markers, such as small membrane capacitance, sensitivity to capsaicin, and slow afterhyperpolarization (AHP); in these neurons the CP-sensitive IDRKcontrols the membrane resting potential, the firing frequency, and the AHP duration. A biophysical study of the CP-sensitive IDRKindicated the presence of two kinetically distinct components: a fast deactivating component having a relatively depolarized steady-state inactivation ( IDRKf) and a slow deactivating component with a more hyperpolarized V1/2for steady-state inactivation ( IDRKs).