bluuebunny/crossref_metadata_2025 huggingface dataset:
RELIABILITY STUDIES OF P3HT: PCBM ORGANIC SOLAR CELLS FABRICATED WITH CALCIUM–ALUMINUM AND LITHIUM FLUORIDE–ALUMINIUM CATHODES
Authors: KRISHNAN T. S. , IYER S. SUNDAR KUMAR
Published: December 2011

This work addresses the shelf life characteristics of P3HT: PCBM blend based organic solar cells (OSC) fabricated with Ca–Al and LiF–Al cathodes. Some of these devices are encapsulated in nitrogen ambient and some in room ambient. Device electrical characteristics are studied under both dark and light. In the analysis under dark ambient conditions, the degradation in peak dark current is monitored over time (in days) and an empirical model is postulated for the degradation based on statistical curve fitting techniques. In the analysis under light, degradation of parameters such as fill factor (FF), open circuit voltage (V oc ) and short circuit current density (J sc ) is monitored over time in these devices (for different cathodes and different ambients) and the results are analyzed and compared. Also, accelerated stress tests are conducted wherein the devices are subjected to continuous illumination for a period of 1.5 h under two different intensities (0.76 sun and 1 sun) and again, the results are analyzed and compared. A model is fitted to the observed degradation in normalized J sc and the degradation constants (k deg ) are obtained. It is seen that the devices fabricated with cathode as LiF–Al and being encapsulated in nitrogen ambient provide the best performance over time.
SYNTHESIS, STRUCTURAL AND MICROSTRUCTURAL STUDIES OF Ni/NiO:ZrO2 NANOCOMPOSITES FOR INTERMEDIATE TEMPERATURE SOLID OXIDE FUEL CELL APPLICATION
Authors: MOHANTY SUBRAT K. , PUROHIT G. , PUROHIT R. D. , SINHA P. K. , MONDAL APARNA , NAYAK BIBHUTI B.
Published: December 2011

The present work emphasizes on the synthesis of Ni (10, 20 and 30 mol%) added tetragonal (t) ZrO 2 nanopowders and Ni / NiO :t- ZrO 2 (50:50 mol%) nanocomposites through precipitation route using hydrazine hydrate ( N 2 H 5 OH ) as a precipitating reagent. In this work, the precipitation route is optimized using different ways. Phase development, particle morphology and phase distributions were studied using X-ray diffraction (XRD), transmission electron microscopy (TEM) and back scattered mode-scanning electron microscopy (SEM), respectively. Structural analysis revealed that the constant pH way is effective in synthesizing Ni :t- ZrO 2 nanopowders up to moderate temperatures as compared to direct or reverse way. The minimum concentrations of Ni for stabilization of t- ZrO 2 (due to incorporation of Ni 2+ in the ZrO 2 lattice) at 700°C and 800°C are 10 mol% and 20 mol%, respectively. Uniform distribution of Ni / NiO phases in ZrO 2 matrix with 35–42% porosity was observed in 50 mol% Ni added t- ZrO 2 nanocomposite pellets, calcined in air and H2 atmosphere. The precipitation method using N 2 H 5 OH for preparing Ni / NiO :t- ZrO 2 nanocomposite powders, is attractive and could be useful in synthesizing anode material for intermediate temperature solid oxide fuel cell application.
H2S DETECTION BY CuO NANOWIRES AT ROOM TEMPERATURE
Authors: KAUR MANMEET , GANAPATHI KAILASA , DATTA NIYANTA , MUTHE K. P. , GUPTA S. K.
Published: December 2011

Room temperature gas sensing properties of CuO nanowires synthesized by thermal oxidation of copper foils was studied in different configurations: (i) isolated nanowires aligned between two electrodes, (ii) as grown CuO foil consisting of nanowires and (iii) CuO nanowire films. Sensors were studied for response to different gases. Different sensors showed qualitatively different response on exposure to H2S . Isolated nanowires showed high sensitivity, (~200% for 10 ppm of gas) and fast response (30 s) and recovery times (60 s). In these samples, the resistance mainly decreased on exposure to H2S (though a small initial increase was observed). In CuO foils, resistance increased for low concentrations (5–10 ppm) but decreased at high concentrations. In the case of CuO nanowire films, resistance only increased on exposure of H2S (upto 400 ppm). Since CuO is a p-type semiconductor, on exposure to H2S an increase in resistance is expected due to oxygen adsorption related process. Decrease in resistance in some of the sensors was understood in terms of reaction of CuO with H2S resulting in the formation of CuS .
EFFECT OF PRE-HEATING AND SEED LAYER ON HYDROTHERMAL GROWTH AND OPTICAL PROPERTIES OF ZINC OXIDE NANORODS
Authors: SHUKLA GAURAV , KHARE ALIKA
Published: December 2011

Hydrothermal growth of highly c-axis oriented ZnO nanorods with high aspect ratio on pulsed laser deposited ZnO seed layer is reported. Effect of pre-heating time, growth time and seed layer on the structural, morphological and optical properties of ZnO nanorods is presented. The possible growth mechanism for ZnO nanorods is also discussed.
THE EFFECT OF RESIDUAL POLY(VINYL ALCOHOL) ON BIOPHYSICAL INTERACTION OF NANOPARTICLES WITH ENDOTHELIAL CELL MODEL MEMBRANE
Authors: BHAVE RADHIKA , PEETLA CHIRANJEEVI , LABHASETWAR VINOD
Published: December 2011

Poly(vinyl alcohol) (PVA) is commonly used as an emulsifier in the formulation of nanoparticles (NPs) comprising poly DL-lactide co-glycolide and polylactide-based biodegradable polymers for drug and gene delivery applications. A fraction of PVA remains associated with the NPs at the interface despite their repeated washing (residual PVA). We hypothesize that this residual PVA influences the interfacial properties of NPs and hence their biophysical interactions with membrane lipids. In this study, we formulated NPs using PVA of different molecular weights to determine the effects of the residual PVA on biophysical interactions of the formulated NPs with the endothelial cell model membrane using a Langmuir balance. Despite similar physical properties (particle size and zeta potential), NPs formulated with different PVA demonstrated significant variations in their intrinsic surface properties and biophysical interactions with the model membrane. This was evident from the difference in the surface pressure–area (π–A) isotherms prepared in the presence of different formulations of NPs and the change in surface pressure of the model membrane following interaction with NPs. The variation in the biophysical properties was observed even with the NPs formulated using the same molecular weight PVA but obtained from different lots. Since the interfacial properties of NPs can significantly influence NP interactions with cells and tissue, their biophysical characterization could prove to be an important parameter not only to obtain consistent results with NPs but also to optimize their properties for drug/gene delivery applications.
THE EFFECT OF MICRON-RUBBER AND NANO-SILICA PARTICLES ON THE FATIGUE CRACK GROWTH BEHAVIOR OF AN EPOXY POLYMER
Authors: MANJUNATHA C. M. , JAGANNATHAN N. , PADMALATHA K. , TAYLOR A. C. , KINLOCH A. J.
Published: December 2011

A thermosetting epoxy polymer was hybrid-modified by incorporating 9 wt.% of CTBN rubber micro particles and 10 wt.% of silica nano-particles. The unmodified and the hybrid-modified resins were poured into steel moulds and cured to produce bulk epoxy polymer sheets from which standard compact tension test specimens were machined. Fatigue crack growth tests were conducted using a 50 kN servo-hydraulic test machine, with the following test parameters: stress ratio, R = σ min /σ max = 0.1, sinusoidal waveform and frequency, ν = 3 Hz. The crack length was monitored by a compliance technique. The fracture surfaces were observed in a high resolution scanning electron microscope. The fatigue crack growth rate of the hybrid epoxy polymer was observed to be significantly lower than that of the unmodified epoxy polymer. The threshold stress intensity factor range, ΔK th , of the epoxy polymer was observed to increase by the addition of micron-rubber and nano-silica particles. The energy dissipating mechanisms viz, (i) cavitation of the rubber microparticles followed by plastic-deformation and void growth of the epoxy and, (ii) silica nanoparticle debonding followed by plastic-deformation and void growth of the epoxy, were observed to be operative and contribute for the reduced crack growth rate in the hybrid epoxy polymer.
MODIFICATION IN OPTICAL AND ELECTRICAL PROPERTIES OF POLY(METHYL METHACRYLATE) ON BLENDING WITH POLYANILINE
Authors: TOMAR A. K. , MAHENDIA SUMAN , KUMAR SHYAM
Published: December 2011

The chemically synthesized Polyaniline (PAni) was characterized through UV-Visible spectroscopy. The appearance of intense peak due to polarons at around 830 nm in electronic absorption spectrum signifies its conducting nature. Characteristics of PMMA–PAni blends with different concentration (by wt) of as-synthesized PAni, prepared via solution casting method, were studied using SEM, UV-Visible spectroscopy and current–voltage (I–V) measurements. Reduction in optical band gap value of PMMA from 3.06 eV to 2.16 eV and about 7 orders of increase in conductivity were observed in PMMA–PAni blend (10% by wt of PAni). Further, investigations of I–V curves suggest the Ohmic conduction in lower voltage region and space-charge limited current (SCLC) as the dominating conduction mechanism at higher voltages (i.e., above 60 V), in both pure PMMA and blended films.
Nitric oxide activates hypoglossal motoneurons by cGMP-dependent inhibition of TASK channels and cGMP-independent activation of HCN channels
Authors: Wenker Ian C. , Benoit Justin P. , Chen Xinnian , Liu Hattie , Horner Richard L. , Mulkey Daniel K.
Published: December 2011

Nitric oxide (NO) is an important signaling molecule that regulates numerous physiological processes, including activity of respiratory motoneurons. However, molecular mechanism(s) underlying NO modulation of motoneurons remain obscure. Here, we used a combination of in vivo and in vitro recording techniques to examine NO modulation of motoneurons in the hypoglossal motor nucleus (HMN). Microperfusion of diethylamine (DEA; an NO donor) into the HMN of anesthetized adult rats increased genioglossus muscle activity. In the brain slice, whole cell current-clamp recordings from hypoglossal motoneurons showed that exposure to DEA depolarized membrane potential and increased responsiveness to depolarizing current injections. Under voltage-clamp conditions, we found that NO inhibited a Ba2+-sensitive background K+ conductance and activated a Cs+-sensitive hyperpolarization-activated inward current ( Ih). When Ih was blocked with Cs+ or ZD-7288, the NO-sensitive K+ conductance exhibited properties similar to TWIK-related acid-sensitive K+ (TASK) channels, i.e., voltage independent, resistant to tetraethylammonium and 4-aminopyridine but inhibited by methanandamide. The soluble guanylyl cyclase blocker 1 H-(1,2,4)oxadiazole(4,3- a)quinoxaline-1-one (ODQ) and the PKG blocker KT-5823 both decreased NO modulation of this TASK-like conductance. To characterize modulation of Ih in relative isolation, we tested effects of NO in the presence of Ba2+ to block TASK channels. Under these conditions, NO activated both the instantaneous ( Iinst) and time-dependent ( Iss) components of Ih. Interestingly, at more hyperpolarized potentials NO preferentially increased Iinst. The effects of NO on Ih were retained in the presence of ODQ and blocked by the cysteine-specific oxidant N-ethylmaleimide. These results suggest that NO activates hypoglossal motoneurons by cGMP-dependent inhibition of a TASK-like current and S-nitrosylation-dependent activation of Ih.
Post Irradiation Spindle Cell Carcinoma of Tonsillar Pillar
Authors: Kinra Prateek , Srinivas V. , Sinha Kavita , Dutta Vibha
Published: December 2011

Spindle cell carcinoma of the tonsillar pillar is a rare malignancy. A case of spindle cell carcinoma of the anterior tonsillar pillar in a 59-year-old man is presented. A growth on the anterior tonsillar pillar, measuring9×7×6 mm, was resected. The neoplasm occurred as a complication of radiotherapy (excessive cumulative radiation dose of 60 Gray) for carcinoma larynx with a latency period of three years. Postradiation spindle cell carcinoma is an uncommon disease manifesting as sarcoma in a previously irradiated field, usually with a latent period of 5 years or more. Literature is limited to small series. Histologically, this tonsillar growth was composed of a squamous cell carcinoma (epithelial component) and a spindle cell sarcomatous component. The two components of the tumour were confirmed using the immunohistochemical staining (cytokeratin and vimentin). Further p53 positivity of the sarcomatous elements aided in ruling out radiation-induced nonmalignant changes of mesenchymal tissue. This paper discusses this rare tumour in a common setting.
Clinical Effectiveness, Access to, and Satisfaction with Care Using a Telehomecare Substitution Intervention: A Randomized Controlled Trial
Authors: Bowles Kathryn H. , Hanlon Alexandra L. , Glick Henry A. , Naylor Mary D. , O'Connor Melissa , Riegel Barbara , Shih Nai-Wei , Weiner Mark G.
Published: December 2011

Background. Hospitalization accounts for 70% of heart failure (HF) costs; readmission rates at 30 days are 24% and rise to 50% by 90 days. Agencies anticipate that telehomecare will provide the close monitoring necessary to prevent HF readmissions.Methods and Results. Randomized controlled trial to compare a telehomecare intervention for patients 55 and older following hospital discharge for HF to usual skilled home care. Primary endpoints were 30- and 60-day all-cause and HF readmission, hospital days, and time to readmission or death. Secondary outcomes were access to care, emergency department (ED) use, and satisfaction with care. All-cause readmissions at 30 days (16% versus 19%) and over six months (46% versus 52%) were lower in the telehomecare group but were not statistically significant. Access to care and satisfaction were significantly higher for the telehomecare patients, including the number of in-person visits and days in home care.Conclusions. Patient acceptance of the technology and current home care policies and processes of care were barriers to gaining clinical effectiveness and efficiency.
Approximately Quintic and Sextic Mappings Form r‐Divisible Groups into Ŝerstnev Probabilistic Banach Spaces: Fixed Point Method
Authors: Eshaghi Gordji M. , Cho Y. J. , Ghaemi M. B. , Majani H.
Published: December 2011

Using the fixed point method, we investigate the stability of the systems of quadratic‐cubic and additive‐quadratic‐cubic functional equations with constant coefficients form r‐divisible groups into Ŝerstnev probabilistic Banach spaces.
Sexual Dysfunction and Hyperprolactinemia in Male Psychotic Inpatients: A Cross-Sectional Study
Authors: Johnsen Erik , Kroken Rune , Løberg Else-Marie , Kjelby Eirik , Jørgensen Hugo A.
Published: December 2011

Introduction. Sexual dysfunction (SD) and hyperprolactinemia are frequently reported in patients with psychotic disorders and have the potential for severe complications but investigations in males are particularly scarce. The primary aims were to determine the prevalence of SD and hyperprolactinemia in male patients and to investigate whether associations exist between SD and prolactin levels.Methods. Cross-sectional data were obtained at discharge from the hospital or 6 weeks after admittance for patients acutely admitted for psychosis and treated with a second-generation antipsychotic drug.Results. Half the patients reported diminished sexual desire and more than a third reported erectile and ejaculatory dysfunctions with no differences among the drugs. More than half the sample was hyperprolactinemic. No association was found between prolactin levels and SD.Conclusion. High rates of SD and hyperprolactinemia were found in male patients and should be a treatment target. SD and hyperprolactinemia were not correlated.
Limit Circle/Limit Point Criteria for Second‐Order Sublinear Differential Equations with Damping Term
Authors: Shao Jing , Song Wei
Published: December 2011

The purpose of the present paper is to establish some new criteria for the classification of the sublinear differential equation as of the nonlinear limit circle type or of the nonlinear limit point type. The criteria presented here generalize some known results in the literature.
Mean‐Square Convergence of Drift‐Implicit One‐Step Methods for Neutral Stochastic Delay Differential Equations with Jump Diffusion
Authors: Hu Lin , Gan Siqing
Published: December 2011

A class of drift‐implicit one‐step schemes are proposed for the neutral stochastic delay differential equations (NSDDEs) driven by Poisson processes. A general framework for mean‐square convergence of the methods is provided. It is shown that under certain conditions global error estimates for a method can be inferred from estimates on its local error. The applicability of the mean‐square convergence theory is illustrated by the stochastic θ‐methods and the balanced implicit methods. It is derived from Theorem 3.1 that the order of the mean‐square convergence of both of them for NSDDEs with jumps is 1/2. Numerical experiments illustrate the theoretical results. It is worth noting that the results of mean‐square convergence of the stochastic θ‐methods and the balanced implicit methods are also new.
Microembolus Detection by Transcranial Doppler Sonography: Review of the Literature
Authors: Vuković-Cvetković Vlasta
Published: December 2011

Transcranial Doppler can detect microembolic signals which are characterized by unidirectional high intensity increase, short duration, random occurrence, and a “whistling” sound. Microembolic signals have been detected in a number of clinical settings: carotid artery stenosis, aortic arch plaques, atrial fibrillation, myocardial infarction, prosthetic heart valves, patent foramen ovale, valvular stenosis, during invasive procedures (angiography, percutaneous transluminal angioplasty), surgery (carotid, cardiopulmonary bypass, orthopedic), and in certain systemic diseases. Microembolic signals are frequent in large artery disease, less commonly detected in cardioembolic stroke, and infrequent in lacunar stroke. This article provides an overview about the current state of technical and clinical aspects of microembolus detection.
Photogenerating Silver Nanoparticles and Polymer Nanocomposites by Direct Activation in the Near Infrared
Authors: Balan Lavinia , Schneider Raphael , Turck Colette , Lougnot Daniel , Morlet-Savary Fabrice
Published: December 2011

This work reports on an improvement of the photochemically assisted synthesis of silver nanoparticles by direct photoreduction of AgNO3 with a laser source emitting in the near infrared range (NIR). For this, polymethine dyes were used as the photoactive agents. Both the effects of central chain structure and activation intensity were investigated. The reduction kinetics was followed up by UV‐Vis spectroscopy, and the particles size was evaluated by transmission electron microscopy. The results showed that light intensity affects both the average size and size distribution of Ag nanoparticles generated through this process. The particles can also be generated in situ in a photopolymerizable formulation so that metal/polymer nanocomposites become available through a one‐step photoassisted process on the basis of NIR activation. The process described herein is very fast (seconds to a few minutes), and it readily lends itself to automatization for mass production of micro‐optical elements implemented directly onto integrated NIR sources.
Focus Issue on Male Infertility
Authors: Kobayashi Hideyuki , Nagao Koichi , Nakajima Koichi
Published: December 2011

Male infertility problems can occur when sperms are limited in number or function. In this paper, we describe the clinical evaluation of male infertility. A detailed history, physical examination, and basic semen analysis are required. In addition, ultrasound, karyotyping, and hormonal studies are needed to determine specific causes of infertility. In addition, the World Health Organization (WHO, 2009) has developed a manual to provide guidance in performing a comprehensive semen analysis. Among the possible reasons for male infertility, nonobstructive azoospermia is the least treatable, because few or no mature sperm may be produced. In many cases, men with nonobstructive azoospermia typically have small-volume testes and elevated FSH. Although treatment may not completely restore the quality of semen from men with subnormal fertility, in some cases a successful pregnancy can still be achieved through assisted reproductive technology.
IFN-γ and indoleamine 2,3-dioxygenase signaling between donor dendritic cells and T cells regulates graft versus host and graft versus leukemia activity
Authors: Lu Ying , Giver Cynthia R. , Sharma Akshay , Li Jian Ming , Darlak Katarzyna A. , Owens Lauren M. , Roback John D. , Galipeau Jacques , Waller Edmund K.
Published: December 2011

Allogeneic hematopoietic stem cell transplantation (HSCT) can eradicate chemorefractory leukemia through the graft-versus-leukemia (GVL) activity of donor T cells. However, the clinical success of allo-HSCT is limited by the graft-versus-host disease (GVHD) activity of donor T cells. We have reported previously that donor bone marrow precursors of plasmacytoid dendritic cells (pre-pDCs) can activate donor T cells toward T-helper 1 immune polarization in murine allogeneic HSCT. To optimize the GVL activity of these activated donor T cells and limit their graft versus host activity, we engineered the cellular constituents of an allogeneic hematopoietic stem cell graft with highly purified hematopoietic stem cells, T cells, and pre-pDCs and studied their GVL and GVHD activities in a murine model of allogeneic HSCT. Transplanted donor pre-pDCs expanded in vivo for 2 weeks after transplant, and they markedly augmented the activation and GVL activity of donor T cells while attenuating their GVHD activity, leading to an improved therapeutic index. Bidirectional signaling between donor T cells and donor pDCs with IFN-γ synthesis by donor T cells inducing indoleamine 2,3-dioxygenase synthesis by donor pDCs limited GVHD by altering the balance between donor T-reg and inflammatory T cells. Manipulating the content of donor DC precursors in allogeneic HSCT is a novel method to optimize the balance between GVL and GVHD.
Population-based survival for malignant mesothelioma after introduction of novel chemotherapy
Authors: Damhuis Ronald A.M. , Schroten Caroline , Burgers Jacobus A.
Published: December 2011

Malignant mesothelioma is known for its dismal prognosis and poor response to conventional treatment. Chemotherapy with cisplatin–antifolate combinations recently showed promising response rates and prolonged survival in randomised trials.

To assess the impact of this development on clinical practice and survival at a population-based level, treatment patterns and survival trends were studied for patients diagnosed with mesothelioma in the period 1995–2006. 4,731 records were retrieved from the Netherlands Cancer Registry and chemotherapy use and median survival were analysed.

For the periods 1995–1998 to 2005–2006, chemotherapy use increased from 8% to 36%. Median survival increased over time from 7.1 months to 9.2 months. For pleural mesothelioma, multivariable analysis demonstrated that survival was poorer for elderly patients and sarcomatoid tumours. The prognostic impact of chemotherapy increased with time. Median survival for chemotherapy treated patients improved from 10.1 months (1995–1998) to 13.1 months (2005–2006). For peritoneal mesothelioma, median survival was poor (3.9 months) but better for females and younger patients.

This study demonstrates that chemotherapy use increased at a national level and coincided with an improvement in survival. The novel chemotherapy regimen appears to be more effective but, due to the observational nature of this study, alternative explanations cannot be excluded.
Recommendations for epidemiological studies on COPD
Authors: Bakke P.S. , Rönmark E. , Eagan T. , Pistelli F. , Annesi-Maesano I. , Maly M. , Meren M. , Vermeire P. , Vestbo J. , Viegi G. , Zielinski J. , Lundbäck B.
Published: December 2011

The prevalence of chronic obstructive pulmonary disease (COPD) has been extensively studied, especially in Western Europe and North America. Few of these data are directly comparable because of differences between the surveys regarding composition of study populations, diagnostic criteria of the disease and definitions of the risk factors. Few community studies have examined phenotypes of COPD and included other ways of characterising the disease beyond that of spirometry.

The objective of the present Task Force report is to present recommendations for the performance of general population studies in COPD in order to facilitate comparable and valid estimates on COPD prevalence by various risk factors.

Diagnostic criteria in epidemiological settings, and standardised methods to examine the disease and its potential risk factors are discussed. The paper also offers practical advice for planning and performing an epidemiological study on COPD.

The main message of the paper is that thorough planning is worth half the study. It is crucial to stick to standardised methods and good quality control during sampling. We recommend collecting biological markers, depending on the specific objectives of the study. Finally, studies of COPD in the population at large should assess various phenotypes of the disease.
Looking to the future: a new decade of pulmonary arterial hypertension therapy
Authors: McLaughlin V.V.
Published: December 2011

Pulmonary arterial hypertension (PAH) is a severe and debilitating disease characterised by vascular proliferation and remodelling of the small pulmonary arteries, leading to a progressive increase in pulmonary vascular resistance, increased afterload on the right ventricle and, ultimately, right heart failure. Although there is no “cure” for PAH, the availability of targeted therapies over the past decade has led to major advances in the management of PAH, reflected in improvements in survival in the modern treatment era. However, despite this, disease progression is inevitable in the majority of patients with PAH and overall the long-term prognosis, although improved, remains poor. There is a clear and urgent need for new therapeutic options, either through the development of improved drugs that act on targets established by existing PAH-specific therapies, or of agents targeting novel pathogenic pathways not addressed by currently available therapies. A number of such new agents that have shown promise in experimental models and preliminary human studies are discussed in this article.
Prognostic factors in pulmonary arterial hypertension: assessing the course of the disease
Authors: Howard L.S.
Published: December 2011

The practical management of pulmonary arterial hypertension (PAH) requires an accurate assessment of disease severity and prognosis. A number of prognostic indicators are known to be associated with patient outcome, and recent treatment guidelines advocate using such parameters to guide management decisions. Although PAH is characterised by the presence of pulmonary vasculopathy, it is the response of the right ventricle to an increased afterload that is the greatest determinant of a patient's symptoms and survival; thus, measurements that capture right ventricular function provide the best potential to assess PAH severity. One challenge is to understand how the tests we use in everyday clinical practice relate to right heart function in PAH patients, and how current measures can be improved and developed to optimise assessment of disease status and progress. Future research in the field of PAH should focus on how best to assess right heart function, and which measures or combination of measures provide the most relevant information for the individual patient.
A Test Method for Monitoring Modulus Changes during Durability Tests on Building Joint Sealants
Authors: White Christopher C. , Hunston Donald L. , Tean Tan Kar
Published: December 2011

The durability of building joint sealants is generally assessed using a descriptive methodology involving visual inspection of exposed specimens for defects. It is widely known that this methodology has inherent limitations, including that the results are qualitative. A new test method is proposed that provides more fundamental and quantitative information about changes occurring in a sealant during durability testing. This test method utilizes a stress relaxation experiment to evaluate the non-linear viscoelastic behavior of sealants. In particular, changes in the time dependence of the apparent modulus can be observed and related to molecular changes in the sealant. Such changes often precede the formation of cracks and theultimate failure of the sealant. This paper compares results obtained from the new test method and the currently used descriptive methodology.
CCAAT/Enhancer Binding Protein-δ Expression by Dendritic Cells Regulates CNS Autoimmune Inflammatory Disease
Authors: Tsai Vicky W. W. , Mohammad Mohammad G. , Tolhurst Ornella , Breit Samuel N. , Sawchenko Paul E. , Brown David A.
Published: December 2011

CCAAT enhancer binding protein-delta (C/EBPδ) is a transcription factor that regulates inflammatory processes mediating bystander neuronal injury and CNS autoimmune inflammatory disease. The mechanism of the involvement of C/EBPδ in these processes remains to be determined. Here, we examined the cellular source(s) and mechanisms by which C/EBPδ may be involved in an animal model of multiple sclerosis. Mice deficient in C/EBPδ expression exhibited less severe clinical disease than wild-type littermates in response to induction of experimental autoimmune encephalomyelitis (EAE) by vaccination with a myelin oligodendrocyte glycoprotein (MOG) fragment. This reduction in EAE severity was associated with a significant alteration in the complement of major CNS T-helper (Th) cell subtypes throughout disease, manifest as reduced ratios of Th17 cells to regulatory T-cells (Tregs). Studies in bone marrow chimeric mice indicated that C/EBPδ expression by peripherally derived immune cells mediates C/EBPδ involvement in EAE. Follow upin vitroandin vivoexamination of dendritic cell (DC) mediated Th-cell development suggests that C/EBPδ suppresses DC expression of interleukin-10 (IL-10), favoring Th17 over Treg development.In vitroandin vivoblockade of IL-10 signaling attenuated the effect of reduced C/EBPδ expression by DCs on Th17:Treg ratios. These findings identify C/EBPδ as an important DC transcription factor in CNS autoimmune inflammatory disease by virtue of its capacity to alter the Th17:Treg balance in an IL-10 dependent fashion.
Homeostatic Strengthening of Inhibitory Synapses Is Mediated by the Accumulation of GABAAReceptors
Authors: Rannals Matthew D. , Kapur Jaideep
Published: December 2011

Mechanisms of homeostatic plasticity scale synaptic strength according to changes in overall activity to maintain stability in neuronal network function. This study investigated mechanisms of GABAergic homeostatic plasticity. Cultured neurons exposed to depolarizing conditions reacted with an increased firing rate (high activity, HA) that normalized to control levels after 48 h of treatment. HA-treated hippocampal neurons displayed an attenuated response to further changes in depolarization, and the firing rate in HA-treated neurons increased above normalized levels when inhibition was partially reduced back to the level of control neurons. The amplitude and frequency of mIPSCs in hippocampal neurons increased after 48 h of HA, and increases in the size of GABAAreceptor γ2 subunit clusters and presynaptic GAD-65 puncta were observed. Investigation of the time course of inhibitory homeostasis suggested that accumulation of GABAAreceptors preceded presynaptic increases in GAD-65 puncta size. Interestingly, the size of GABAAreceptor γ2 subunit clusters that colocalized with GAD-65 were larger at 12 h, coinciding in time with the increase found in mIPSC amplitude. The rate of internalization of GABAAreceptors, a process involved in regulating the surface expression of inhibitory receptors, was slower in HA-treated neurons. These data also suggest that increased receptor expression was consolidated with presynaptic changes. HA induced an increase in postsynaptic GABAAreceptors through a decrease in the rate of internalization, leading to larger synaptically localized receptor clusters that increased GABAergic synaptic strength and contributed to the homeostatic stabilization of neuronal firing rate.
Attentional Modulation of Neuromagnetic Evoked Responses in Early Human Visual Cortex and Parietal Lobe following a Rank-Order Rule
Authors: Lennert Therese , Cipriani Roberto , Jolicoeur Pierre , Cheyne Douglas , Martinez-Trujillo Julio C.
Published: December 2011

Top-down voluntary attention modulates the amplitude of magnetic evoked fields in the human visual cortex. Whether such modulation is flexible enough to adapt to the demands of complex tasks in which abstract rules must be applied to select a target in the presence of distracters remains unclear. We recorded brain neuromagnetic activity using whole-head magnetoencephalography in 14 human subjects during a rule-guided target selection task, and applied event-related Synthetic Aperture Magnetometry to image instantaneous changes in neuromagnetic source activity throughout the brain. During the task subjects selected one of two stimuli (the target) and ignored the other (the distracter) based on a color-rank rule (color 1 > color 2 > color 3). Our results revealed that in early visual color-sensitive areas and the parietal cortex visual stimuli evoke activity that scaled following the rank-order rule. This effect was stronger and occurred later in the parietal lobe (∼200 ms after target/distracter onset) relative to early visual areas (∼180 ms). Moreover, we found that transient changes in the target's motion direction evoked stronger responses relative to similar changes in the distracter at ∼180 ms from change onset in contralateral areas hMT+/V5. These results suggest that during target selection and allocation of attention to a stimulus, top-down signals adjust their intensity following complex selection rules according to the organism's priorities, thereby differentially modulating neuromagnetic activity across visual cortical areas.
Functional characterization of a rare germline mutation in the gene encoding the cyclin-dependent kinase inhibitor p27Kip1 (CDKN1B) in a Spanish patient with multiple endocrine neoplasia-like phenotype
Authors: Malanga Donatella , De Gisi Silvia , Riccardi Miriam , Scrima Marianna , De Marco Carmela , Robledo Mercedes , Viglietto Giuseppe
Published: December 2011

Objective

The aim of this study was to investigate the presence of germline mutations in theCDKN1Bgene that encodes the cyclin-dependent kinase (Cdk) inhibitor p27 in multiple endocrine neoplasia 1 (MEN1)-like Spanish index patients. TheCDKN1Bgene has recently been identified as a tumor susceptibility gene for MEN4, with six germline mutations reported so far in patients with a MEN-like phenotype but negative for MEN1 mutations.

Design and methods

Fifteen Spanish index cases with MEN-like symptoms were screened for mutations in theCDKN1Bgene and the mutant variant was studied functionally by transcription/translation assaysin vitroand in transiently transfected HeLa cells.

Results

We report the identification of a heterozygous GAGA deletion in the 5′-UTR ofCDKN1B, NM_004064.3:c.-32_-29del, in a patient affected by gastric carcinoid tumor and hyperparathyroidism. This deletion falls inside the region that is responsible forCDKN1Btranscription and is predicted to destroy a secondary stem and loop structure that includes the GAGAGA element responsible for ribosome recruitment. Accordingly,in vitrostudies of coupled transcription/translation assays and transient transfection in HeLa cells showed that the GAGA deletion in theCDKN1B5′-UTR significantly impairs the transcription of downstream reporter luciferase (of ∼40–60%) and, possibly, the translation of the corresponding mRNA. This mutation was associated with a significant reduction in the amount ofCDKN1BmRNA in peripheral blood leukocytes from the patient, as demonstrated by quantitative real-time PCR.

Conclusions

Our results confirm that germlineCDKN1Bmutations may predispose to a human MEN4 condition and add novel evidence that alteration in the transcription/translation rate ofCDKN1BmRNA might be the mechanism implicated in tumor susceptibility.
The Structure of Genealogies in the Presence of Purifying Selection: A Fitness-Class Coalescent
Authors: Walczak Aleksandra M , Nicolaisen Lauren E , Plotkin Joshua B , Desai Michael M
Published: December 2011

Compared to a neutral model, purifying selection distorts the structure of genealogies and hence alters the patterns of sampled genetic variation. Although these distortions may be common in nature, our understanding of how we expect purifying selection to affect patterns of molecular variation remains incomplete. Genealogical approaches such as coalescent theory have proven difficult to generalize to situations involving selection at many linked sites, unless selection pressures are extremely strong. Here, we introduce an effective coalescent theory (a “fitness-class coalescent”) to describe the structure of genealogies in the presence of purifying selection at many linked sites. We use this effective theory to calculate several simple statistics describing the expected patterns of variation in sequence data, both at the sites under selection and at linked neutral sites. Our analysis combines a description of the allele frequency spectrum in the presence of purifying selection with the structured coalescent approach of Kaplan et al. (1988), to trace the ancestry of individuals through the distribution of fitnesses within the population. We also derive our results using a more direct extension of the structured coalescent approach of Hudson and Kaplan (1994). We find that purifying selection leads to patterns of genetic variation that are related but not identical to a neutrally evolving population in which population size has varied in a specific way in the past.
Increasing rubella seronegativity despite a compulsory school law.
Authors: Schum T R , Nelson D B , Duma M A , Sedmak G V
Published: December 2011

To determine if lower rubella susceptibility persisted five to seven years after immunization legislation, we retrospectively reviewed the serologic status of 341 outpatients from 1985 to 1987 in an inner-city school age population. Seronegative rates increased significantly during the two-year study period from 4.2 to 24.5 percent (17 percent overall). (Beta = 6.8%, 95% CI = 3.3, 10.3). Charts were reviewed for 57 of 58 seronegative and 114 seropositive controls. Estimates were then made to the population of 341 subjects. Those with documented rubella immunization had a seronegative rate of 13 percent compared to 19 percent if the immunization status was unknown. For patients who received care in our clinic for less than two years, 32 percent were seronegative compared to 10 percent for those treated greater than or equal to 2 years (odds ratio = 0.31, 95% CI = 0.16, 0.60). Among patients immunized in 1977 or 1978, 33 percent were seronegative compared to 7 percent immunized at other times (OR = 0.21, 95% CI = 0.07, 0.63). Factors associated with increased rubella seronegativity include immunization in 1977 or 1978 and lack of continuity of care in our clinic. Much of the increase remains unexplained.
The health consequences of maquiladora work: women on the US-Mexican border.
Authors: Guendelman S , Silberg M J
Published: December 2011

OBJECTIVES. As more US companies take jobs to Mexico, complaints are growing that the assembly plants (maquiladoras) exert adverse effects on workers' health. This study assessed the health of female electronic and garment maquiladora workers, comparing them with women employed in services and non-wage earners. METHODS. A survey was administered to 480 women living in Tijuana in 1990. The sample was stratified by occupation and length of employment. Functional impediments, nervousness, depression, and sense of control were used as outcome variables, controlling for other confounders. RESULTS. Despite working longer hours, receiving lower wages, and having less decision latitude and education, maquiladora workers were not worse off than service workers. Maquiladora workers reported similar incidences of depression and lack of control over life. Electronics workers, especially, had lower incidences of nervousness and functional impediments, after controlling for other confounders. Also, maquiladora work did not add an extra health burden compared with non-wage earners. CONCLUSIONS. The adverse effects of maquiladoras previously reported may have been exaggerated. Subjective factors, including negative attitudes toward economic adversity and work dissatisfaction, were stronger predictors of health than were objective indicators.
Risk factors associated with HIV infection among male prostitutes.
Authors: Elifson K W , Boles J , Sweat M
Published: December 2011

OBJECTIVES. This study documents the human immunodeficiency virus (HIV) and sexually transmitted disease seroprevalence rate for male prostitutes, identifies the risk factors for HIV, and provides baseline information for the development and implementation of appropriate prevention and intervention strategies. METHODS. Structured interviews were conducted with and blood samples were collected from 235 actively working male prostitutes in Atlanta, Georgia, from July 1988 through July 1991. RESULTS. The HIV seroprevalence was 29.4%; 25.1% of the sample had seromarker for syphilis and 58.3% for hepatitis B. Multivariate logistic regression analysis showed the following significant HIV risk factors: history of receptive anal sex with nonpaying partners, serologic history of hepatitis B or syphilis, and history of childhood physical abuse. CONCLUSIONS. The reported seroprevalence rates among these male prostitutes indicate they are a high-risk group. The striking difference in HIV seroprevalence by sexual orientation may warrant special attention. Considering the public health consequences, there is a clear need for innovative HIV prevention and intervention among these men.
The effects of a 4-year program promoting bicycle helmet use among children in Quebec.
Authors: Farley C , Haddad S , Brown B
Published: December 2011

OBJECTIVES. This study assessed the effectiveness of a 4-year program of bicycle helmet promotion that targeted elementary school children in one region of Quebec. The program revolved primarily around persuasive communication and community organization, combining standard educational activities and activities to facilitate helmet acquisition and use. METHODS. Helmet use was compared between more than 8000 young cyclists in municipalities exposed or not exposed to the program. Factors influencing helmet use were controlled through the use of multivariate analyses. RESULTS. Helmet use increased from 1.3% before program implementation to 33% in 1993. The program was clearly effective in most cycling circumstances and for various groups of children. However, the benefits of the program were unequally distributed; the program was one third as effective in poorer municipalities as in "average-rich" ones. CONCLUSIONS. This community-based program that combined various types of activities appeared to be effective. New intervention models are needed to ensure an equitable distribution of benefits.
Consequences in Georgia of a nationwide outbreak of Salmonella infections: what you don't know might hurt you.
Authors: Mahon B E , Slutsker L , Hutwagner L , Drenzek C , Maloney K , Toomey K , Griffin P M
Published: December 2011

OBJECTIVES: This study assessed the impact in Georgia of a nationwide salmonellosis outbreak caused by ice cream products and the effectiveness of the subsequent warning against eating the implicated products. METHODS: A telephone survey of 250 randomly selected Georgia customers of the ice cream producer was conducted 13 to 17 days after the warning. RESULTS: Respondents from 179 households representing 628 persons were interviewed. The median date of first hearing the warning was 5 days after it was issued, and 16 respondents (9%) had not heard it. Among those who had heard the warning, 42 (26%) did not initially believe the products were unsafe. In 22 (31%) of the 72 households that had the implicated ice cream when the respondent heard the warning, someone subsequently ate the ice cream. Diarrhea was reported in 26% (121/463) of persons who had eaten the products but in only 5% (8/152) who had not (odds ratio [controlling for household clustering] = 3.8; 95% confidence interval = 2.0, 7.5). We estimate this outbreak caused 11,000 cases of diarrhea in Georgia, 1760 (16%) with exposure after the warning. CONCLUSIONS: A large outbreak occurred in Georgia, much of which might have been prevented by a more timely and convincing warning.
Vasectomy in the United States, 1991 and 1995.
Authors: Magnani R J , Haws J M , Morgan G T , Gargiullo P M , Pollack A E , Koonin L M
Published: December 2011

OBJECTIVES: This study sought to assess whether the controversy surrounding publications linking vasectomy and prostate cancer has had an effect on vasectomy acceptance and practice in the United States. METHODS: National probability surveys of urology, general surgery, and family practices were undertaken in 1992 and 1996. RESULTS: Estimates of the total number of vasectomies performed, population rate, and proportion of practices performing vasectomy were not significantly different in 1991 and 1995. CONCLUSIONS: This study provides no solid evidence that the recent controversy over prostate cancer has influenced vasectomy acceptance or practice in the United States. However, the use of vasectomy appears to have leveled off in the 1990s.
Macrolevel Stressors, Terrorism, and Mental Health Outcomes: Broadening the Stress Paradigm
Authors: Richman Judith A. , Cloninger Lea , Rospenda Kathleen M.
Published: December 2011

Objectives. We examined the extent to which the stress paradigm linking psychosocial stressors to mental health status has focused disproportionate attention on microlevel social stressors to the detriment of macrolevel stressors. Also, we assessed the effects of the terrorist attacks of September 11, 2001, on subsequent mental health among participants in a Midwestern cohort study.

Methods. Respondents in a 6-wave longitudinal mail survey completed questionnaires before September 11, 2001, and again in 2003 and 2005. Regression analyses focused on measures of negative terrorism-related beliefs and fears, as well as psychological distress and deleterious alcohol use outcomes measured both before and after September 11.

Results. Negative terrorism-related beliefs and fears assessed in 2003 predicted distress and drinking outcomes in 2005 after control for sociodemographic characteristics and pre–September 11 distress and drinking.

Conclusions. The events of September 11 continue to negatively affect the mental health of the American population. Our results support the utility of according greater attention to the effects of such macrolevel social stressors in population studies embracing the stress paradigm.
A Decade of Research on Disparities in Medicare Utilization: Lessons for the Health and Health Care of Vulnerable Men
Authors: Gornick Marian E.
Published: December 2011

Medicare research has shown that there are substantial disparities by race and socioeconomic status in use of services. In this article, I review past research and discuss how findings apply specifically to vulnerable men aged 65 years or older.

Six lessons from this review are identified and illustrated here. Disparities in certain measures of health are growing; to reverse this trend, substantial efforts are needed, including dissemination of information about disparities as well as testing of hypotheses regarding underlying causes.