bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Fragmentation of AlON and Spinel Under Ballistic Impact
Authors: Strassburger Elmar , Hunzinger Martin , Patel Parimal , McCauley James W.
Published: February 2013

It has been demonstrated that significant weight reductions can be achieved, compared to conventional glass-based armor, when a transparent ceramic is used as the strike face on a glass-polymer laminate. Magnesium aluminate spinel (MgAl2O4) and AlON are promising candidate materials for application as a hard front layer in transparent armor. Comprehensive, systematic investigations of the fragmentation of ceramics have shown that the mode of fragmentation is one of the key parameters influencing the ballistic resistance of ceramics. In the study described here, the fragmentation of AlON and three types of spinel was analyzed: two types of fine grained spinel with nominal average grain sizes 0.6 μm and 1.6 μm and a bimodal grain-sized spinel with large grains of 250 μm size in a fine grain (5–20 μm) matrix were examined. The ceramic specimens of 6-mm thickness were glued to an aluminum backing and impacted with armor piercing (AP) projectiles of caliber 7.62 mm at two different velocities—850 m/s and 1100 m/s. The targets were integrated into a target box, which allowed for an almost complete recovery and analysis of the ceramic fragments. Different types of high-speed cameras were applied in order to visualize the different phases of fragment formation and ejection. A laser light-sheet illumination technique was applied in combination with high-speed cameras in order to determine size and speed of ejected ceramic fragments during projectile penetration. The application of the visualization techniques allowed for the analysis of the dynamics of the fragment formation and interaction with the projectile. A significant difference in the fragment size distributions of bimodal grain-sized spinel and AlON was observed.
Fast Food Linked to Asthma and Allergies in Children
Authors: Reznik Marina
Published: February 2013

Fast food intake is associated with increased risk of severe asthma, rhinoconjunctivitis, and eczema in youth.
Structural and Functional Analysis of the Pore-Forming Toxin NetB from Clostridium perfringens
Authors: Yan Xu-Xia , Porter Corrine J. , Hardy Simon P. , Steer David , Smith A. Ian , Quinsey Noelene S. , Hughes Victoria , Cheung Jackie K. , Keyburn Anthony L. , Kaldhusdal Magne , Moore Robert J. , Bannam Trudi L. , Whisstock James C. , Rood Julian I.
Published: February 2013

Clostridium perfringens
is an anaerobic bacterium that causes numerous important human and animal diseases, primarily as a result of its ability to produce many different protein toxins. In chickens,
C. perfringens
causes necrotic enteritis, a disease of economic importance to the worldwide poultry industry. The secreted pore-forming toxin NetB is a key virulence factor in the pathogenesis of avian necrotic enteritis and is similar to alpha-hemolysin, a β-barrel pore-forming toxin from
Staphylococcus aureus
. To address the molecular mechanisms underlying NetB-mediated tissue damage, we determined the crystal structure of the monomeric form of NetB to 1.8 Å. Structural comparisons with other members of the alpha-hemolysin family revealed significant differences in the conformation of the membrane binding domain. These data suggested that NetB may recognize different membrane receptors or use a different mechanism for membrane-protein interactions. Consistent with this idea, electrophysiological experiments with planar lipid bilayers revealed that NetB formed pores with much larger single-channel conductance than alpha-hemolysin. Channel conductance varied with phospholipid net charge. Furthermore, NetB differed in its ion selectivity, preferring cations over anions. Using hemolysis as a screen, we carried out a random-mutagenesis study that identified several residues that are critical for NetB-induced cell lysis. Mapping of these residues onto the crystal structure revealed that they were clustered in regions predicted to be required for oligomerization or membrane binding. Together these data provide an insight into the mechanism of NetB-mediated pore formation and will contribute to our understanding of the mode of action of this important toxin.

IMPORTANCE
Necrotic enteritis is an economically important disease of the worldwide poultry industry and is mediated by
Clostridium perfringens
strains that produce NetB, a β-pore-forming toxin. We carried out structural and functional studies of NetB to provide a mechanistic insight into its mode of action and to assist in the development of a necrotic enteritis vaccine. We determined the structure of the monomeric form of NetB to 1.8 Å, used both site-directed and random mutagenesis to identify key residues that are required for its biological activity, and analyzed pore formation by NetB and its substitution-containing derivatives in planar lipid bilayers.
RidA Proteins Prevent Metabolic Damage Inflicted by PLP-Dependent Dehydratases in All Domains of Life
Authors: Lambrecht Jennifer A. , Schmitz George E. , Downs Diana M.
Published: February 2013

Pyridoxal 5′-phosphate (PLP) is a coenzyme synthesized by all forms of life. Relevant to the work reported here is the mechanism of the PLP-dependent threonine/serine dehydratases, which generate reactive enamine/imine intermediates that are converted to keto acids by members of the RidA family of enzymes. The RidA protein of
Salmonella enterica
serovar Typhimurium LT2 is the founding member of this broadly conserved family of proteins (formerly known as YjgF/YER057c/UK114). RidA proteins were recently shown to be enamine deaminases. Here we demonstrate the damaging potential of enamines in the absence of RidA proteins. Notably,
S. enterica
strains lacking RidA have decreased activity of the PLP-dependent transaminase B enzyme IlvE, an enzyme involved in branched-chain amino acid biosynthesis. We reconstituted the threonine/serine dehydratase (IlvA)-dependent inhibition of IlvE
in vitro
, show that the
in vitro
system reflects the mechanism of RidA function
in vivo
, and show that IlvE inhibition is prevented by RidA proteins from all domains of life. We conclude that 2-aminoacrylate (2AA) inhibition represents a new type of metabolic damage, and this finding provides an important physiological context for the role of the ubiquitous RidA family of enamine deaminases in preventing damage by 2AA.

IMPORTANCE
External stresses that disrupt metabolic components can perturb cellular functions and affect growth. A similar consequence is expected if endogenously generated metabolites are reactive and persist in the cellular environment. Here we show that the metabolic intermediate 2-aminoacrylate (2AA) causes significant cellular damage if allowed to accumulate aberrantly. Furthermore, we show that the widely conserved protein RidA prevents this accumulation by facilitating conversion of 2AA to a stable metabolite. This work demonstrates that the reactive metabolite 2AA, previously considered innocuous in the cell due to a short half-life in aqueous solution, can survive in the cellular environment long enough to cause damage. This work provides insights into the roles and persistence of reactive metabolites
in vivo
and shows that the RidA family of proteins is able to prevent damage caused by a reactive intermediate that is created as a consequence of PLP-dependent chemistry.
Carbon Catabolite Control in Candida albicans: New Wrinkles in Metabolism
Authors: Lorenz Michael C.
Published: February 2013

Most microorganisms maintain strict control of nutrient assimilation pathways to ensure that they preferentially use compounds that generate the most energy or are most efficiently catabolized. In doing so, they avoid potentially inefficient conflicts between parallel catabolic and metabolic pathways. The regulation of carbon source utilization in a wide array of bacterial and fungal species involves both transcriptional and posttranscriptional mechanisms, and while the details can vary significantly, carbon catabolite control is widely conserved. In many fungi, the posttranslational aspect (carbon catabolite inactivation [CCI]) involves the ubiquitin-mediated degradation of catabolic enzymes for poor carbon sources when a preferred one (glucose) becomes available. A recent article presents evidence for a surprising exception to CCI in the fungal pathogen
Candida albicans
, an organism that makes use of gluconeogenic carbon sources during infection (D. Sandai, Z. Yin, L. Selway, D. Stead, J. Walker, M. D. Leach, I. Bohovych, I. V. Ene, S. Kastora, S. Budge, C. A. Munro, F. C. Odds, N. A. Gow, and A. J. Brown,
mBio
3[6]:e00495-12).
In vitro
, addition of glucose to cells grown in a poor carbon source rapidly represses transcripts encoding gluconeogenic and glyoxylate cycle enzymes, such as phosphoenolpyruvate carboxykinase (Pck1p) and isocitrate lyase (Icl1p), in both
C. albicans
and
Saccharomyces cerevisiae
. Yet, uniquely, the
C. albicans
proteins persist, permitting parallel assimilation of multiple carbon sources, likely because they lack consensus ubiquitination sites found in the yeast homologs. Indeed, the yeast proteins are rapidly degraded when expressed in
C. albicans
, indicating a conservation of the machinery needed for CCI. How this surprising metabolic twist contributes to fungal commensalism or pathogenesis remains an open question.
Next-Generation Sequencing of Small RNAs from HIV-Infected Cells Identifies Phased microRNA Expression Patterns and Candidate Novel microRNAs Differentially Expressed upon Infection
Authors: Chang Stewart T. , Thomas Matthew J. , Sova Pavel , Green Richard R. , Palermo Robert E. , Katze Michael G.
Published: February 2013

HIV infection of CD4
+
T cells induces a range of host transcriptional changes in mRNAs as well as microRNAs that may coordinate changes in mRNAs. To survey these dynamic changes, we applied next-generation sequencing, analyzing the small RNA fraction of HIV-infected cells at 5, 12, and 24 h postinfection (RNA-Seq). These time points afforded a view of the transcriptomic changes occurring both before and during viral replication. In the resulting small RNA-Seq data set, we detected a phased pattern of microRNA expression. Largely distinct sets of microRNAs were found to be suppressed at 5 and 12 h postinfection, and both sets of changes rebounded later in infection. A larger set of microRNA changes was observed at 24 h postinfection. When integrated with mRNA expression data, the small RNA-Seq data indicated a role for microRNAs in transcriptional regulation, T cell activation, and cell cycle during HIV infection. As a unique benefit of next-generation sequencing, we also detected candidate novel host microRNAs differentially expressed during infection, including one whose downregulation at 24 h postinfection may allow full replication of HIV to proceed. Collectively, our data provide a uniquely comprehensive view of the changes in host microRNAs induced by HIV during cellular infection.

IMPORTANCE
New sequencing technologies allow unprecedented views into changes occurring in virus-infected cells, including comprehensive and largely unbiased measurements of different types of RNA. In this study, we used next-generation sequencing to profile dynamic changes in cellular microRNAs occurring in HIV-infected cells. The sensitivity afforded by sequencing allowed us to detect changes in microRNA expression early in infection, before the onset of viral replication. A phased pattern of expression was evident among these microRNAs, and many that were initially suppressed were later overexpressed at the height of infection, providing unique signatures of infection. By integrating additional mRNA data with the microRNA data, we identified a role for microRNAs in transcriptional regulation during infection and specifically a network of microRNAs involved in the expression of a known HIV cofactor. Finally, as a distinct benefit of sequencing, we identified candidate nonannotated microRNAs, including one whose downregulation may allow HIV-1 replication to proceed fully.
An unusual presentation of an amoebic liver abscess: the story of an unwanted souvenir
Authors: Swaminathan Vikram , O'Rourke Joanne , Gupta Rashmi , Kiire C F
Published: February 2013

This case was rather unusual with regard to the disease presentation. The patient had non-specific symptoms of weight loss and general malaise, without any history of preceding diarrhoea or dysentery. It is important to be aware of the epidemiology of the disease, and to relate it to patients presenting with symptoms suggestive of amoebiasis. We discuss the recommended investigations and management options for these patients based on the current guidelines/evidence.
Ureteric obstruction secondary to retroperitoneal fibrosis leading to acute kidney injury
Authors: Bjorndalen Harald , Hastings Robert A
Published: February 2013

A 65-year-old man presenting with apparent acute coronary syndrome was found to have an acute kidney injury. A CT scan of the abdomen revealed bilateral hydronephrosis secondary to retroperitoneal fibrosis, and an unruptured infrarenal abdominal aortic aneurysm Medical management with corticosteroids relieved the ureteric obstruction and renal function started to normalise within 72 h.
High pleural ammonia negatively interferes with the measurement of adenosine deaminase activity
Authors: Loh Tze Ping , Tan Karen Mei Ling , Chew Suru , Chan Douglas S G
Published: February 2013

Pleural adenosine deaminase activity (ADA) is a sensitive and specific test for tuberculous pleurisy. Here, we report a case of undetectable ADA in the pleural fluid of a man presenting with chronic cough, fever and night sweats. Subsequent laboratory investigations and review revealed that the presence of high concentrations of ammonia in pleural fluid, commonly seen in empyema, negatively interferes with ADA results when measured by the Guisti and Galanti method. The source of ammonia may come from deamination of amino acids, ammonia-producing microbes and/or leucocytes. This interference invalidates ADA results and is present in ∼2% of our laboratory requests. It is important to keep this interference in mind when tuberculosis/ammonia-producing bacteria coinfections are suspected and during early phases of tuberculous pleurisy, when neutrophils predominate in the pleural fluids.
Air pollution exposure in early pregnancy and adverse pregnancy outcomes: a register-based cohort study
Authors: Olsson David , Mogren Ingrid , Forsberg Bertil
Published: February 2013

Objectives

Our aim was to study the possible associations between exposure to elevated levels of air pollution, ozone (O3) and vehicle exhaust (NOx), during early gestation, and adverse pregnancy outcomes such as pre-eclampsia, preterm birth and small for gestational age.

Design

Prospective register-based cohort study.

Setting

The Swedish Medical Birth Register includes data on all deliveries during 1998 to 2006 in Greater Stockholm, Sweden. The national Patient Register and the Prescribed Drug Register were used to collect information on maternal asthma.

Participants

All singleton pregnancies, conceived at the earliest in August 1997 and at the latest in February 2006, were included, n=120 755.

Outcome measures

We studied preterm birth, small for gestational age and pre-eclampsia.

Results

4.4% of pregnancies resulted in a preterm birth. The prevalence of pre-eclampsia was 2.7%. We observed an association between first trimester O3and preterm birth (OR 1.04, 95% CI 1.01 to 1.08) as well as an association with pre-eclampsia (OR 1.04, 95% CI 1.01 to 1.08), per 10 µg/m3increase in O3. We observed no association between first trimester NOxand adverse pregnancy outcomes. No associations were observed between any of the air pollutants and small for gestational age.

Conclusions

Increased levels of O3during the first trimester increased the risk of pre-eclampsia and preterm birth. Air pollutants did not exhibit any effects on fetal growth restriction. We estimated 1 in every 20 cases of pre-eclampsia to be associated with O3exposure.
A cross-sectional study of workplace social capital and blood pressure: a multilevel analysis at Japanese manufacturing companies
Authors: Fujino Yoshihisa , Kubo Tatsuhiko , Kunimoto Masamizu , Tabata Hidetoshi , Tsuchiya Takuto , Kadowaki Koji , Nakamura Takehiro , Oyama Ichiro
Published: February 2013

Objectives

We examined the contextual effect of workplace social capital on systolic blood pressure (SBP).

Design

Cross-sectional.

Setting

A conglomerate from 58 workplaces in Japan.

Participants

Of the 5844 workers at a Japanese conglomerate from 58 workplaces, 5368 were recruited. Individuals who received drugs for hypertension (n=531) and who lacked information on any variable (n=167) were excluded from the analyses, leaving 4735 individuals (3281 men and 1454 women) for inclusion.

Primary and secondary outcome measures

Systolic blood pressure.

Results

The contextual effect of workplace social capital on SBP was examined using a multilevel regression analysis with a random intercept. Coworker support had a contextual effect at the workplace level (coefficient=−1.97, p=0.043), while a lack of trust for coworkers (coefficient=0.27, p=0.039) and lack of helpfulness from coworkers were associated with SBP (coefficient=0.28, p=0.002).

Conclusions

The present study suggested that social capital at the workplace level has beneficial effects on SBP.
Treatment quality indicators predict short-term outcomes in patients with diabetes: a prospective cohort study using the GIANTT database
Authors: Sidorenkov Grigory , Voorham Jaco , Zeeuw Dick de , Haaijer-Ruskamp Flora M , Denig Petra
Published: February 2013

Objective

To assess whether quality indicators for treatment of cardiovascular and renal risk factors are associated with short-term outcomes in patients with diabetes.

Design

A prospective cohort study using linear regression adjusting for confounders.

Setting

The GIANTT database (Groningen Initiative to Analyse Type 2 Diabetes Treatment) containing data from primary care medical records from The Netherlands.

Participants

15 453 patients with type 2 diabetes mellitus diagnosed before 1 January 2008. Mean age 66.5 years, 47.5% men.

Exposure

Quality indicators assessing current treatment (CT) status or treatment intensification (TI) for patients with diabetes with elevated cardiovascular or renal risk factors.

Main outcome measures

Low-density lipoprotein cholesterol (LDL-C), systolic blood pressure (SBP), and albumin:creatinine ratio (ACR) before and after assessment of treatment quality.

Results

Use of lipid-lowering drugs was associated with better LDL-C levels (−0.41 mmol/litre; 95% CI −0.48 to −0.34). Use of blood pressure-lowering drugs and use of renin–angiotensin system inhibitors in patients with elevated risk factor levels was not associated with better SBP and ACR outcomes, respectively. TI was also associated with better LDL-C (−0.82 mmol/litre; CI −0.93 to −0.71) in patients with elevated LDL-C levels, and with better SBP (−1.26 mm Hg; CI −2.28 to −0.24) in patients with two elevated SBP levels. Intensification of albuminuria-lowering treatment showed a tendency towards better ACR (−2.47 mmol/mg; CI −5.32 to 0.39) in patients with elevated ACR levels.

Conclusions

Quality indicators of TI were predictive of better short-term cardiovascular and renal outcomes, whereas indicators assessing CT status showed association only with better LDL-C outcome.
Do you have to re-examine to reconsider your diagnosis? Checklists and cardiac exam
Authors: Sibbald Matthew , de Bruin Anique B H , Cavalcanti Rodrigo B , van Merrienboer Jeroen J G
Published: February 2013

Background

Few studies have investigated whether clinicians can use checklists to verify their diagnostic decisions. Checklists may improve accuracy by prompting clinicians to reconsider or recollect information but might impair decision making by adding to clinicians’ cognitive load. This study assessed whether checklists improve cardiac exam diagnostic accuracy, and whether this benefit is dependent on collecting additional information.

Methods

191 internal medicine residents examined a cardiopulmonary simulator. They provided a diagnosis, subjective rating of certainty, and key findings before and after using a checklist. Residents were randomised; half were allowed access to the simulator and half were prohibited access to the simulator while using the checklist. Residents rated their cognitive load in each step: prechecklist diagnosis, checklist use and postchecklist diagnosis.

Result

Verifying with a checklist resulted in improved diagnostic accuracy; 88 residents (46%) made the correct diagnosis before using the checklist compared with 97 (51%) afterwards, p=0.04. The benefit of checklist use was restricted to residents allowed to re-examine the simulator (10 changed to correct diagnosis and one to an incorrect diagnosis) whereas no net benefit was seen among residents unable to re-examine the simulator (two changed to a correct diagnosis and two to an incorrect diagnosis, p=0.03). Those able to re-examine the simulator were slightly more confident after checklist use, whereas those unable to re-examine were slightly less confident after checklist use (p=0.01). The opportunity to re-examine the simulator had no effect on the accuracy of key findings reported. Of the three steps, checklist use was associated with the lowest cognitive load (F1,189=68 p<0.001).

Conclusions

Verifying diagnostic decisions with a checklist improved diagnostic accuracy. This benefit was only seen when more information could be collected. Checklist use was not associated with increased cognitive load.
Maternal cell phone and cordless phone use during pregnancy and behaviour problems in 5-year-old children
Authors: Guxens Mònica , van Eijsden Manon , Vermeulen Roel , Loomans Eva , Vrijkotte Tanja G M , Komhout Hans , van Strien Rob T , Huss Anke
Published: February 2013

Background

A previous study found an association between maternal cell phone use during pregnancy and maternal-reported child behaviour problems at age 7. Together with cell phones, cordless phones represent the main exposure source of radiofrequency-electromagnetic fields to the head. Therefore, we assessed the association between maternal cell phone and cordless phone use during pregnancy and teacher-reported and maternal-reported child behaviour problems at age 5.

Methods

The study was embedded in the Amsterdam Born Children and their Development study, a population-based birth cohort study in Amsterdam, the Netherlands (2003–2004). Teachers and mothers reported child behaviour problems using the Strength and Difficulties Questionnaire at age 5. Maternal cell phone and cordless phone use during pregnancy was asked when children were 7 years old.

Results

A total of 2618 children were included. As compared to non-users, those exposed to prenatal cell phone use showed an increased but non-significant association of having teacher-reported overall behaviour problems, although without dose-response relationship with the number of calls (OR=2.12 (95% CI 0.95 to 4.74) for <1 call/day, OR=1.58 (95% CI 0.69 to 3.60) for 1–4 calls/day and OR=2.04 (95% CI 0.86 to 4.80) for ≥5 calls/day). ORs for having teacher-reported overall behaviour problems across categories of cordless phone use were below 1 or close to unity. Associations of maternal cell phone and cordless phone use with maternal-reported overall behaviour problems remained non-significant. Non-significant associations were found for the specific behaviour problem subscales.

Conclusion

Our results do not suggest that maternal cell phone or cordless phone use during pregnancy increases the odds of behaviour problems in their children.
Evaluating reintroduction methods for the Gulf of Saint Lawrence aster (Symphyotrichum laurentianum) on Prince Edward Island
Authors: Atkinson Kerry-Lynn , Lacroix Christian
Published: February 2013

The Gulf of St. Lawrence aster (SLA; Symphyotrichum laurentianum (Fernald) G.L. Nesom) is an annual plant species endemic to the Gulf of St. Lawrence region. Owing to the dynamic nature of the environment that the SLA inhabits, severe and major threats to both the aster and its habitat exist. The Committee on the Status of Endangered Wildlife in Canada listed the species as threatened in Canada in 2004. This status was assigned based on the species' limited distribution, fluctuating population size, and continued pressures on its habitat. Surveys have revealed that both site and population numbers have been further and drastically reduced on Prince Edward Island. In 2007, only one populated site of 482 individuals remained. It is possible that this species has been extirpated from Prince Edward Island. Recovery of this species on Prince Edward Island is feasible. Promising results related to seeding and the transplantation of greenhouse-grown seedlings at four in situ sites demonstrated that SLA plantlets have the potential to serve as seed stock to re-establish populations. Over the 2 years of the transplantation experiment, the pooled overall survivorship was 52.8%. Specific site manipulations that were tested may also increase the potential survivorship of the transplants and facilitate second-generation germination.
Genetic variation and reproductive mode in two epiphytic lichens of conservation concern: a transatlantic study ofEvernia divaricataandUsnea longissima
Authors: Rolstad Jørund , Ekman Stefan , Andersen Heidi Lie , Rolstad Erlend
Published: February 2013

North European epiphytic lichens are often genetically impoverished compared with their North American counterparts. This has been hypothesized to impede sexual reproduction due to reduced chances of finding compatible mating type partners. We compared genetic variation and reproductive mode in two threatened Scandinavian lichens, Evernia divaricata and Usnea longissima, with more viable populations in North America to see (i) if these species also show genetical depletion in northern Europe and (ii) if the occurrence of sexual propagules (ascospores in apothecia) is more prevalent in genetically diverse populations. Genetic variation of the fungal component was assessed by sequencing two nuclear rDNA gene regions (ITS and IGS) in 1005 and 1477 thalli, collected from 92 and 160 localities of E. divaricata and U. longissima, respectively. Scandinavian populations of both species were almost devoid of genetic variation compared with much higher genetic diversity in North America. We found no support for the proposed relationship between genetic diversity and fertility. Fertile thalli were found in several genetically invariable populations. Fertility increased with population size and regional abundance in E. divaricata, but not in U. longissima. In Scandinavia, E. divaricata was more fertile than previously recorded, whereas all sampled populations of U. longissima were sterile and possibly clonal.
A WEIGHTED NETWORK EVOLUTION WITH TRAFFIC FLOW UNDER PREFERENTIAL ATTACHMENT
Authors: DAI MEIFENG , LU RONGRONG
Published: February 2013

With more attentions drawn to transportation, we find that it is available to analyze transportation system by using weighted networks. Distinguishing from traditional method, we introduce a dynamic weighted network model with evolutional size and weight. Additionally, the expected strength allocation vector of the model consists of a deterministic component reflecting preferential attachment and a random component, which can characterize the realistic network better. In this paper, we obtain the degree and strength distributions of the weighted network and we conclude that the network has scale-free characteristics.
LOCAL ENTANGLEMENT ENTROPY AT THE MOTT METAL-INSULATOR TRANSITION IN INFINITE DIMENSIONS
Authors: SU DAN-DAN , DAI XI , TONG NING-HUA
Published: February 2013

We study the critical behavior of the single-site entanglement entropy S at the Mott metal-insulator transition in infinite-dimensional Hubbard model. For this model, the entanglement between a single site and rest of the lattice can be evaluated exactly, using the dynamical mean-field theory (DMFT). Both the numerical solution using exact diagonalization and the analytical one using two-site DMFT gives S - Sc∝ α log2[(1/2 - Dc)/Dc](U - Uc), with Dcthe double occupancy at Ucand α < 0 being different on two sides of the transition.
DIELECTRIC PROPERTIES OF Ca2CuO3–CaCu2O3–CuO COMPOSITE CERAMICS
Authors: LI QING-SHOU , ZHANG YUN-QIANG , LI LI-BEN , ZANG GUO-ZHONG
Published: February 2013

The Ca 2 CuO 3– CaCu 2 O 3– CuO ceramics were synthesized by traditional solid-state sintering method. The complex dielectric response of the samples measured from 102–106 Hz and from 300–500 K reveals very high real part of ε > 104. The activation energy (being about 0.63 eV) calculated by the Arrhenius equation indicates that the oxygen vacancies may contribute to the high dielectric response. And the fitting to a Schottky barrier model of capacitance versus applied voltage suggests that the existence of Schottky barrier at the grain boundaries may be another important reason for the origination of good dielectric properties.
ADVANCED ANALYSIS OF STEEL–CONCRETE COMPOSITE BEAM-COLUMNS BY REFINED PLASTIC HINGE METHOD
Authors: FONG M. , CHAN S. L.
Published: February 2013

Based on the second-order inelastic analysis, this paper presents a practical method of design for steel–concrete composite beam-columns that satisfies code performance requirements. The concept of second-order inelastic analysis for structures is to consider both geometric and material nonlinearities and their imperfections so that the real structural behavior can be captured and the assumption for effective lengths is not required. The refined plastic hinge approach proposed herein traces the gradual material yielding and simulates full plasticity of a cross-section. The definitions of the initial and full yield surfaces (which are used to initiate the yielding and to indicate the full plastic stage) for steel–concrete composite cross-sections, based on the cross-section analysis, are presented. The proposed method is verified in examples of isolated composite columns and frames.
MULTIBODY DYNAMIC MODELING AND FLUTTER ANALYSIS OF A FLEXIBLE SLENDER VEHICLE
Authors: RASTI A. , FAZELZADEH S. A.
Published: February 2013

In this paper, multibody dynamic modeling and flutter analysis of a flexible slender vehicle are investigated. The method is a comprehensive procedure based on the hybrid equations of motion in terms of quasi-coordinates. The equations consist of ordinary differential equations for the rigid body motions of the vehicle and partial differential equations for the elastic deformations of the flexible components of the vehicle. These equations are naturally nonlinear, but to avoid high nonlinearity of equations the elastic displacements are assumed to be small so that the equations of motion can be linearized. For the aeroelastic analysis a perturbation approach is used, by which the problem is divided into a nonlinear flight dynamics problem for quasi-rigid flight vehicle and a linear extended aeroelasticity problem for the elastic deformations and perturbations in the rigid body motions. In this manner, the trim values that are obtained from the first problem are used as an input to the second problem. The body of the vehicle is modeled with a uniform free–free beam and the aeroelastic forces are derived from the strip theory. The effect of some crucial geometric and physical parameters and the acting forces on the flutter speed and frequency of the vehicle are investigated.
A PERIDYNAMICS FORMULATION BASED HIERARCHICAL MULTISCALE MODELING APPROACH BETWEEN CONTINUUM SCALE AND ATOMISTIC SCALE
Authors: RAHMAN R. , HAQUE A.
Published: February 2013

In this paper, a multiscale modeling framework has been established between peridynamics and atomistic models. Peridynamics (PD) formulation is based on continuum theory implying nonlocal force based interactions. Peridynamics (PD) and molecular dynamics (MD) have similarities since both use nonlocal force based interaction. It means continuum points in PD and MD atoms are separated by finite distance and exert force upon each other. In this work PD based continuum model of epoxy polymer is defined by meshless Lagrangian particles. MD is coupled with PD based continuum model through a hierarchical multiscale modeling framework. In this framework, PD particles at coarse scale interact with fine scale PD particles by transferring pressure, displacements and velocities among each other. Based on the same hierarchical coupling method, fine scale PD model is seamlessly interfaced with molecular model through an intermediate mesoscale region i.e. coarse-grain atomic model. At the end of this hierarchical downscaling, the information — such as deformation, energy and other important parameters — were captured in the atomistic region under the applied force at micro and macro regions. A two-dimensional plate of neat epoxy was considered for demonstration of such multiscale simulation platform. The region of interest in the 2D plate was interfaced with atomistic model by applying the proposed hierarchical coupling method. The results show reasonable consistency between PD and MD simulations.
Cardiac mitochondrial proteomic expression in inbred rat strains divergent in survival time after hemorrhage
Authors: Klemcke Harold G. , DeKroon Robert M. , Mocanu Mihaela , Robinette Jennifer B. , Alzate Oscar
Published: February 2013

We have previously identified inbred rat strains differing in survival time to a severe controlled hemorrhage (StaH). In efforts to identify cellular mechanisms and ultimately genes that are important contributors to enhanced STaH, we conducted a study to characterize potential differences in cardiac mitochondrial proteins in these rats. Inbred rats from three strains [Brown Norway/Medical College of Wisconsin (BN); Dark Agouti (DA), and Fawn Hooded Hypertensive (FHH)] with different StaH (DA = FHH > BN) were assigned to one of three treatment groups ( n = 4/strain): nonoperated controls, surgically catheterized rats, or rats surgically catheterized and hemorrhaged 24 h postsurgery. Rats were euthanized 30 min after handling or 30 min after initiation of a 26 min hemorrhage. After euthanasia, hearts were removed and mitochondria isolated. Differential protein expression was determined using 2D DIGE-based Quantitative Intact Proteomics and proteins identified by MALDI/TOF mass spectrometry. Hundreds of proteins (791) differed among inbred rat strains ( P ≤ 0.038), and of these 81 were identified. Thirty-eight were unique proteins and 43 were apparent isoforms. For DA rats (longest STaH), 36 proteins increased and 30 decreased compared with BN (shortest STaH). These 81 proteins were associated with lipid (e.g., acyl CoA dehydrogenase) and carbohydrate (e.g., fumarase) metabolism, oxidative phosphorylation (e.g., ubiquinol-cytochrome C reductase), ATP synthesis (F1ATPase), and H2S synthesis (3-mercaptopyruvate sulfurtransferase). Although we cannot make associations between these identified mitochondrial proteins and StaH, our data do provide evidence for future candidate proteins with which to consider such associations.
Treatment of a Multitraumatized Tortured Refugee Needing an Interpreter with Exposure Therapy
Authors: Jensen Bo Søndergaard
Published: February 2013

This paper described the application and feasibility of exposure therapy treatment (ET) for posttraumatic stress disorder (PTSD) in a multitraumatized tortured refugee with chronic PTSD and depression, in need of an interpreter. The patient received 26 one-hour sessions of ET involving exposure to his trauma-related memories. Symptoms of PTSD, depression, and anxiety were assessed at pre- and posttreatment and 3-, 6-, and 12-month followup with the Harvard Trauma Questionnaire (HTQ-R), PTSD Symptom Scale-Self Report (PSS-SR), Major depression inventory (MDI), and Beck Anxiety Inventory (BAI). Treatment led to a significant improvement across all measures of posttraumatic stress disorder, anxiety, and depression, and the improvement was maintained at the 12-month follow-up. The results from this case study provide further preliminary evidence that ET may be effective in treating multi-traumatized torture survivors who are refugees and in need of an interpreter, despite the additional stressors and symptoms complexity experienced by tortured refugees.
Comparison of Oral Tolerance to ApoB and HSP60 Peptides in Preventing Atherosclerosis Lesion Formation in Apob48−/Ldlr− Mice
Authors: Mundkur Lakshmi , Mukhopadhyay Rupak , Deshpande Vrushali , Samson Sonia , Tarate Sagar , Varma Meenakshi , Sneha T. S. , Lu Xinjie , Kakkar Vijay V.
Published: February 2013

Antigen-specific immune modulation is emerging as an attractive therapeutic option to prevent
atherosclerosis. We compared the efficacy of oral administration of peptides derived from apolipoprotein B (ApoB; 661–680) and heat shock protein 60 (HSP60; 153–163), in the
prevention of atherosclerotic lesion formation hyperlipidemic low density lipoprotein receptordeficient (LDLr−/−), apolipoprotein B-100 only (apoB100/100) mice model. Oral administration of peptides induced tolerance as seen by an increase in regulatory T cells in the peripheral immune system. Tolerance to ApoB peptide reduced plaque development by 28.7% (P<0.001) while HSP60 was effective in reducing lesion development by 26.8% in ApoB48/LDLr−/− mice. While tolerance to HSP60 resulted in increase in anti-inflammatory cytokines (IL10 and TGF-β), ApoB tolerance was effective in reducing the lipid deposition in the lesion. Our results suggest that the two peptides have distinct mechanisms of controlling the development of atherosclerosis in mice.
The (Real) Neurogenic/Gliogenic Potential of the Postnatal and Adult Brain Parenchyma
Authors: Bonfanti Luca
Published: February 2013

During the last two decades basic research in neuroscience has remarkably expanded due to the discovery of neural stem cells (NSCs) and adult neurogenesis in the mammalian central nervous system (CNS). The existence of such unexpected plasticity triggered hopes for alternative approaches to brain repair, yet deeper investigation showed that constitutive mammalian neurogenesis is restricted to two small “neurogenic sites” hosting NSCs as remnants of embryonic germinal layers and subserving homeostatic roles in specific neural systems. The fact that in other classes of vertebrates adult neurogenesis is widespread in the CNS and useful for brain repair sometimes creates misunderstandings about the real reparative potential in mammals. Nevertheless, in the mammalian CNS parenchyma, which is commonly considered as “nonneurogenic,” some processes of gliogenesis and, to a lesser extent, neurogenesis also occur. This “parenchymal” cell genesis is highly heterogeneous as to the position, identity, and fate of the progenitors. In addition, even the regional outcomes are different. In this paper the heterogeneity of mammalian parenchymal neurogliogenesis will be addressed, also discussing the most common pitfalls and misunderstandings of this growing and promising research field.
Hypertension Management in the High Cardiovascular Risk Population
Authors: Maraj Ilir , Makaryus John N. , Ashkar Anthony , McFarlane Samy I. , Makaryus Amgad N.
Published: February 2013

The incidence of hypertension is increasing every year. Blood pressure (BP) control is an important therapeutic goal for the slowing of progression as well as for the prevention of Cardiovascular disease. The management of hypertension in the high cardiovascular risk population remains a real challenge as the population continues to age, the incidence of diabetes increases, and more and more people survive acute myocardial infarction. We will review hypertension management in the high cardiovascular risk population: patients with coronary heart disease (CHD) and heart failure (HF) as well as in diabetic patients.
A Histopathological and Immunohistochemical Analysis of Ameloblastic Fibrodentinoma
Authors: Bologna-Molina Ronell , Salazar-Rodríguez Sirced , Bedoya-Borella Ana María , Carreón-Burciaga Ramón Gil , Tapia-Repetto Gabriel , Molina-Frechero Nelly
Published: February 2013

Ameloblastic fibrodentinoma (AFD) is considered a mixed odontogenic tumor that is characterized by conserved epithelial and ectomesenchymal neoplastic components. AFD is composed of long narrow cords and islands of odontogenic epithelium; the epithelial strands lie in a myxoid cell-rich ectomesenchymal tissue with stellate-shaped fibroblasts that exhibit long slender cytoplasmic extensions that resemble dental papilla. The lesions show the presence of dysplastic dentin. Although AFD is a rare entity and its very existence is not completely accepted, based on the extent of histodifferentiation, it is considered to represent a stage between ameloblastic fibroma and ameloblastic fibroodontoma. This study aimed to provide a histopathological and immunohistochemical characterization of this infrequent tumor. A large panel of antibodies including amelogenin, Ck 19, calretinin, syndecan-1, E-cadherin, MSH2, histone H3, and Ki-67 was used to illustrate the nature of the tumor.
Calprotectin Is a Useful Tool in Distinguishing Coexisting Irritable Bowel-Like Symptoms from That of Occult Inflammation among Inflammatory Bowel Disease Patients in Remission
Authors: Jelsness-Jørgensen Lars-Petter , Bernklev Tomm , Moum Bjørn
Published: February 2013

Background and Aim. In the inflammatory bowel diseases (IBDs), many symptoms are similar to the functional disorder irritable bowel syndrome (IBS). A challenge is thus to distinguish symptoms of IBD from IBS. The aim of this study was to investigate the levels of calprotectin in IBS-positive IBD patients in remission.Methods. Remission was defined as a simple clinical colitis activity index (SCCAI) or simple crohn’s disease activity index (SCDAI) score of less than three and less than four, respectively. The Rome II criteria were used to identify cases, and the calprotectin ELISA test was used to quantify calprotectin in stools.Results. The Rome II criteria were fulfilled in 24.6% of ulcerative colitis (UC) patients, while the comparable number for Crohn's disease (CD) was 21.4%. There was a tendency for elevated fecal calprotectin levels in IBS-positive patients, regardless of diagnosis. However, these differences were only significant in CD.Conclusions. Calprotectin levels are elevated in subgroups of IBD patients that are in remission and have coexisting IBS-like symptoms. This study underscores the clinical usefulness of a noninvasive marker to distinguish patients in need of intensified followup from those that do not need further workup.
On-Line Selection ofc-Alternating Subsequences from a Random Sample
Authors: Chen Robert W. , Shepp Larry A. , Yang Justín Ju-Chen
Published: February 2013

A sequence is a -alternating sequence if any odd term is less than or equal to the next even term and the any even term is greater than or equal to the next odd term , where is a nonnegative constant. In this paper, we present an optimal on-line procedure to select a -alternating subsequence from a symmetric distributed random sample. We also give the optimal selection rate when the sample size goes to infinity.
A Unique Dermoscopy Pattern of Solitary Cutaneous Reticulohistiocytosis
Authors: de Oliveira Felipe Ladeira , Nogueira Letycia Lopes Chagas , Chaves Gabriel Monteiro de Castro , Muniz Mariana Daflon Vinhosa , Timbó Renata Pinto Fernandes , Sasse Mariana Martins , Meotti Carolina Degen
Published: February 2013

Histiocytosis represents a group of rare disorders characterized by nonneoplastic proliferation of histiocytes and solitary cutaneous reticulohistiocytosis (SCR) is a form of non-Langerhans histiocytosis. SCR consists of small papule, usually single, varying in color from yellow to brownish-red, more frequent in young adults, and uncommon in childhood. We report a case of SCR in an 11-year-old child and emphasize a unique dermoscopy pattern of this lesion and its correlation with clinical and histopathological aspects in the diagnosis.
Metabolic Syndrome and Cardiovascular Risk Factors in a National Sample of Adolescent Population in the Middle East and North Africa: The CASPIAN III Study
Authors: Khashayar Patricia , Heshmat Ramin , Qorbani Mostafa , Motlagh Mohammad Esmaeil , Aminaee Tahere , Ardalan Gelayol , Farrokhi-Khajeh-Pasha Yasin , Taslimi Mahnaz , Larijani Bagher , Kelishadi Roya
Published: February 2013

Objective. The present study was designed to investigate the prevalence of different combinations of the metabolic syndrome (MetS) risk factors among a nationally representative sample of adolescents in the Middle East and North Africa (MENA).Methods. The study sample, obtained as part of the third study of the school-based surveillance system entitled CASPIAN III, was representative of the Iranian adolescent population aged from 10 to 18 years. The prevalence of different components of MetS was studied and their discriminative value was assessed by receiver operating characteristic (ROC) curve analysis.Results. The study participants consisted of 5738 students (2875 girls) with mean age of14.7±2.4years) living in 23 provinces in Iran; 17.4% of participants were underweight and 17.7% were overweight or obese. Based on the criteria of the International Diabetes Federation for the adolescent age group, 24.2% of participants had one risk factor, 8.0% had two, 2.1% had three, and 0.3% had all the four components of MetS. Low HDL-C was the most common component (43.2% among the overweight/obese versus 34.9% of the normal-weight participants), whereas high blood pressure was the least common component. The prevalence of MetS was 15.4% in the overweight/obese participants, the corresponding figure was 1.8% for the normal-weight students, and 2.5% in the whole population studied. Overweight/obese subjects had a 9.68 increased odds of (95% CI: 6.65–14.09) the MetS compared to their normal-weight counterparts. For all the three risk factors, AUC ranged between 0.84 and 0.88, 0.83 and 0.87, and 0.86 and 0.89 in waist circumference, abdominal obesity, and BMI for boys and between 0.78 and 0.97, 0.67 and 0.93, and 0.82 and 0.96 for girls, respectively.Conclusion. The findings from this study provide alarming evidence-based data on the considerable prevalence of obesity, MetS, and CVD risk factors in the adolescent age group. These results are confirmatory evidence for the necessity of primordial/primary prevention of noncommunicable disease should be considered as a health priority in communities facing a double burden of nutritional disorders.
Relationship between Serum Levels of OPG and TGF-βwith Decreasing Rate of BMD in Native Chinese Women
Authors: Wu Xi-Yu , Peng Yi-Qun , Zhang Hong , Xie Hui , Sheng Zhi-Feng , Luo Xiang-Hang , Dai Ru-Chun , Zhou Hou-De , Wu Xian-Ping , Liao Er-Yuan
Published: February 2013

The objective of this study was to investigate the relationship between serum levels of OPG, TGF-β1, and TGF-β2 and BMD decrease rate (BDR) in native Chinese women. This cross-sectional study was performed on 465 healthy native Chinese women aged 35–80 years. Serum levels of OPG, TGF-β1, and TGF-β2 were determined. BDR was measured by DXA at the posteroanterior spine, hip, and distal forearm. At all skeletal sites tested, there was a negative correlation between BDR and serum levels of both OPG (r=−0.122to –0.230, allP= 0.007–0.000) and TGF-β2 (r=−0.100to –0.173, allP= 0.029–0.000) and a positive correlation between BDR and serum TGF-β1 (r=0.245−0.365, allP=0.000). After adjustment for age and BMI, there were no statistically significant correlations between serum levels of OPG or TGF-β2 and BDR. However, statistically significant correlations between serum TGF-β1 and BDR at the lumbar spine and ultradistal forearm remained. Multiple linear regression stepwise analysis showed that serum OPG could explain 1.4–3.7% of BDR variation. Serum TGF-β1 was a positive determinant of BDR and could explain 5.3–13.3% of BDR variation.
On Entire and Meromorphic Functions That Share One Small Function with Their Differential Polynomial
Authors: Bhoosnurmath Subhas S. , Kabbur Smita R.
Published: February 2013

We study the uniqueness of meromorphic functions that share one small function with more general differential polynomial P[f]. As corollaries, we obtain results which answer open questions posed by Yu (2003).