bluuebunny/crossref_metadata_2025 huggingface dataset:
E-Learning Quality
Authors: Mena Marta
Published: April 2012

The evaluation issue has acquired significant importance in recent years and has increased concern about the analysis of educational practices’ quality. This chapter deals with the concept of quality and asks about the different aspects that define it. It develops certain criteria that allow for assessing good e-learning practices. The first aspects that are necessary to define are: (a) the pursued purpose and (b) the Institution’s structural configuration. Good practice evidences are: a direct relation between the program proposal and the intervention context; coherence between theory and practice; presence of interactive and multimedia materials together with permanent interaction; strategies and devices especially designed to support learning; appropriate technology; permanent evaluating research; and a clear human resources policy.
Major Functional Transcriptome of an Inferred Center Regulator of an ER(–) Breast Cancer Model System
Authors: Liu Li-Yu Daisy , Chang Li-Yun , Kuo Wen-Hung , Hwa Hsiao-Lin , Lin Yi-Shing , Huang Shiu-Feng , Chen Chiung-Nien , Chang King-Jen , Hsieh Fon-Jou
Published: April 2012

We aimed to find clinically relevant gene activities ruled by the signal transducer and activator of transcription 3 ( STAT3) proteins in an ER(–) breast cancer population via network approach. STAT3 is negatively associated with both lymph nodal category and stage. MYC is a component of STAT3 network. MYC and STAT3 may co-regulate gene expressions for Warburg effect, stem cell like phenotype, cell proliferation and angiogenesis. We identified a STAT3 network in silico showing its ability in predicting its target gene expressions primarily for specific tumor subtype, tumor progression, treatment options and prognostic features. The aberrant expressions of MYC and STAT3 are enriched in triple negatives (TN). They promote histological grade, vascularity, metastasis and tumor anti-apoptotic activities. VEGFA, STAT3, FOXM1 and METAP2 are druggable targets. High levels of METAP2, MMP7, IGF2 and IGF2R are unfavorable prognostic factors. STAT3 is an inferred center regulator at early cancer development predominantly in TN.
Optimal Polynomial Recurrence
Authors: Lyall Neil , Magyar Ákos
Published: April 2012

Let P ∊ ℤ[n] with P(0) = 0 and “ > 0. We show, using Fourier analytic techniques, that if then there must exist n ∊ ℕ such that

In addition to this we show, using the same Fourier analytic methods, that if A ⊆ ℕ, then the set
of ε-optimal return times

is syndetic for every ε > 0. Moreover, we show that R(A, P, ε) is dense in every sufficiently long interval, in particular we show that there exists an L = L(ε, P, A) such that

for all intervals I of natural numbers with
Global Well-Posedness and Convergence Results for the 3D-Regularized Boussinesq System
Authors: Selmi Ridha
Published: April 2012

Analytical study of the regularization of the Boussinesq systemis performed in frequency space using Fourier theory. Existence and uniqueness of weak solutions with minimum regularity requirement are proved. Convergence results of the unique weak solution of the regularized Boussinesq system to a weak Leray-Hopf solution of the Boussinesq system are established as the regularizing parameterαvanishes. The proofs are done in the frequency space and use energy methods, the Arselà-Ascoli compactness theorem and a Friedrichs-like approximation scheme.
Resultants of Chebyshev Polynomials: A Short Proof
Authors: Louboutin Stéphane R.
Published: April 2012

We give a simple proof of the value of the resultant of two Chebyshev polynomials (of the first or the second kind), values lately obtained by D. P. Jacobs, M. O. Rayes, and V. Trevisan.
Estimates for Compositions of Maximal Operators with Singular Integrals
Authors: Richard Oberlin
Published: April 2012

We prove weak-type (1, 1) estimates for compositions of maximal operators with singular integrals. Our main object of interest is the operator Δ*Ψ where Δ* is Bourgain’s maximal multiplier operator and is the sum of several modulated singular integrals; here our method yields a significantly improved bound for theLqoperator norm when 1 <q< 2. We also consider associated variation-norm estimates.
Optimal Control Strategies for Virus Spreading in Inhomogeneous Epidemic Dynamics
Authors: Shang Yilun
Published: April 2012

In this paper, we study the spread of virus/worm in computer networks with a view to addressing cyber security problems. Epidemic models have been applied extensively to model the propagation of computer viruses, which characterize the fact that infected machines may spread malware to other hosts connected to the network. In our framework, the dynamics of hosts evolves according to a modified inhomogeneous Susceptible-Infectious-Susceptible (SIS) epidemic model with time-varying transmission rate and recovery rate. The infection of computers is subject to direct attack as well as propagation among hosts. Based on optimal control theory, optimal attack strategies are provided by minimizing the cost (equivalently maximizing the profit) of the attacker. We present a threshold function of the fraction of infectious hosts, which captures the dynamically evolving strategies of the attacker and reflects the persistence of virus spreading. Moreover, our results indicate that if the infectivity of a computer worm is low and the computers are installed with antivirus software with high reliability, the intensity of attacks incurred will likely be low. This agrees with our intuition.
On the Radius of Comparison of a Commutative C*-algebra
Authors: Elliott George A. , Niu Zhuang
Published: April 2012

Let X be a compact metric space. A lower bound for the radius of comparison of the C*-algebra C(X) is given in terms of dimQ X, where dimQ X is the cohomological dimension with rational coefficients. If dimQX = dim X = d, then the radius of comparison of the C*-algebra C(X) is maxf0; (d/1)=2/1g if d is odd, and must be either d=2/1 or d=2/2 if d is even (the possibility d=2 - 1 does occur, but we do not know if the possibility d=2 - 2 can also occur).
The 2009–2010 Arctic stratospheric winter – general evolution, mountain waves and predictability of an operational weather forecast model
Authors: Dörnbrack A. , Pitts M. C. , Poole L. R. , Orsolini Y. J. , Nishii K. , Nakamura H.
Published: April 2012

Abstract. The relatively warm 2009–2010 Arctic winter was an exceptional one as the North Atlantic Oscillation index attained persistent extreme negative values. Here, selected aspects of the Arctic stratosphere during this winter inspired by the analysis of the international field experiment RECONCILE are presented. First of all, and as a kind of reference, the evolution of the polar vortex in its different phases is documented. Special emphasis is put on explaining the formation of the exceptionally cold vortex in mid winter after a sequence of stratospheric disturbances which were caused by upward propagating planetary waves. A major sudden stratospheric warming (SSW) occurring near the end of January 2010 concluded the anomalous cold vortex period. Wave ice polar stratospheric clouds were frequently observed by spaceborne remote-sensing instruments over the Arctic during the cold period in January 2010. Here, one such case observed over Greenland is analysed in more detail and an attempt is made to correlate flow information of an operational numerical weather prediction model to the magnitude of the mountain-wave induced temperature fluctuations. Finally, it is shown that the forecasts of the ECMWF ensemble prediction system for the onset of the major SSW were very skilful and the ensemble spread was very small. However, the ensemble spread increased dramatically after the major SSW, displaying the strong non-linearity and internal variability involved in the SSW event.
Are simulated aerosol-induced effects on deep convective clouds strongly dependent on saturation adjustment?
Authors: Lebo Z. J. , Morrison H. , Seinfeld J. H.
Published: April 2012

Abstract. Three configurations of a bulk microphysics scheme in conjunction with a detailed bin scheme are implemented in the Weather Research and Forecasting (WRF) model to specifically address the role of the saturation adjustment assumption (i.e., condensing/evaporating the surplus/deficit water vapor relative to saturation in one time step) on aerosol-induced invigoration of deep convective clouds. The bulk model configurations are designed to treat cloud droplet condensation/evaporation using either saturation adjustment, as employed in most bulk models, or an explicit representation of supersaturation over a time step, as used in bin models. Results demonstrate that the use of saturation adjustment artificially enhances condensation and latent heating at low levels and limits the potential for an increase in aerosol concentration to increase buoyancy at mid to upper levels. This leads to a small weakening of the time- and domain-averaged convective mass flux (~ -3%) in polluted compared to clean conditions. In contrast, the bin model and bulk scheme with explicit prediction of supersaturation simulate an increase in latent heating aloft and the convective updraft mass flux is weakly invigorated (~5%). The bin model also produces a large increase in domain-mean cumulative surface precipitation in polluted conditions (~18%), while all of the bulk model configurations simulate little change in precipitation. Finally, it is shown that the cold pool weakens substantially with increased aerosol loading when saturation adjustment is applied, which acts to reduce the low-level convergence and weaken the convective dynamics. With an explicit treatment of supersaturation in the bulk and bin models there is little change in cold pool strength, so that the convective response to polluted conditions is influenced more by changes in latent heating aloft. It is concluded that the use of saturation adjustment can explain differences in the response of cold pool evolution and convective dynamics with aerosol loading simulated by the bulk and bin models, but cannot explain large differences in the response of surface precipitation between these models.
A new method to calibrate aerodynamic roughness over the Tibetan Plateau using Ensemble Kalman Filter
Authors: Lee J. H. , Timmermans J. , Su Z. , Mancini M.
Published: April 2012

Abstract. Aerodynamic roughness height (Zom) is a key parameter required in land surface hydrological model, since errors in heat flux estimations are largely dependent on accurate optimization of this parameter. Despite its significance, it remains an uncertain parameter that is not easily determined. This is mostly because of non-linear relationship in Monin-Obukhov Similarity (MOS) and unknown vertical characteristic of vegetation. Previous studies determined aerodynamic roughness using traditional wind profile method, remotely sensed vegetation index, minimization of cost function over MOS relationship or linear regression. However, these are complicated procedures that presume high accuracy for several other related parameters embedded in MOS equations. In order to simplify a procedure and reduce the number of parameters in need, this study suggests a new approach to extract aerodynamic roughness parameter via Ensemble Kalman Filter (EnKF) that affords non-linearity and that requires only single or two heat flux measurement. So far, to our knowledge, no previous study has applied EnKF to aerodynamic roughness estimation, while a majority of data assimilation study has paid attention to land surface state variables such as soil moisture or land surface temperature. This approach was applied to grassland in semi-arid Tibetan area and maize on moderately wet condition in Italy. It was demonstrated that aerodynamic roughness parameter can inversely be tracked from data assimilated heat flux analysis. The aerodynamic roughness height estimated in this approach was consistent with eddy covariance result and literature value. Consequently, this newly estimated input adjusted the sensible heat overestimated and latent heat flux underestimated by the original Surface Energy Balance System (SEBS) model, suggesting better heat flux estimation especially during the summer Monsoon period. The advantage of this approach over other methodologies is that aerodynamic roughness height estimated in this way is useful even when eddy covariance data are absent and is time-variant over vegetation growth, as well as is not affected by saturation problem of remotely sensed vegetation index.
Monoamine Oxidase A and B Gene Polymorphisms and Negative and Positive Symptoms in Schizophrenia
Authors: Camarena Beatriz , Fresán Ana , Aguilar Alejandro , Escamilla Raúl , Saracco Ricardo , Palacios Jorge , Tovilla Alfonso , Nicolini Humberto
Published: April 2012

Given that schizophrenia is a heterogeneous disorder, the analysis of clinical characteristics could help to identify homogeneous phenotypes that may be of relevance in genetic studies. Linkage and association studies have suggested that a locus predisposing to schizophrenia may reside within Xp11. We analyzed uVNTR and rs1137070, polymorphisms fromMAOAand rs1799836 ofMAOBgenes to perform single SNP case-control association study in a sample of 344 schizophrenia patients and 124 control subjects. Single polymorphism analysis of uVNTR, rs1137070 and rs1799836 SNPs did not show statistical differences between cases and controls. Multivariate ANOVA analysis of clinical characteristics showed statistical differences betweenMAOB/rs1799836 and affective flattening scores (F=4.852,P=0.009), and significant association betweenMAOA/uVNTR and affective flattening in female schizophrenia patients (F=4.236,P=0.016) after Bonferroni’s correction. Our preliminary findings could suggest that severity of affective flattening may be associated by modifier variants ofMAOAandMAOBgenes in female Mexican patients with schizophrenia. However, further large-scale studies using quantitative symptom-based phenotypes and several candidate variants should be analyzed to obtain a final conclusion.
President's page
Authors: Sonnenwald Diane H.
Published: April 2012

Editor's Summary

Despite its name, the American Society for Information Science and Technology (ASIS&T) is an international organization, embracing its geographically diverse membership. As a global scholarly organization, ASIS&T has responsibilities and considerations that reach far beyond local and national concerns. That breadth of concern is reflected in deeds, such as a reduced membership fee for those in less developed countries, as well as in words. Including “American” in the name may convey pride and distinction but creates obstacles for some. It is time to consider a name change that accurately reflects the scope and goals of the organization. Members are invited to comment until May 1, 2012, on a change that retains the acronym “ASIS&T” while revising the title to ASsociation for Information Science & Technology.
Digital humanities and information visualization: Innovation and integration
Authors: Beaudoin Joan , Buchanan Sarah
Published: April 2012

Editor's Summary

The chairs of Special Interest Group/Arts & Humanities and Special Interest Group/Visualization, Images and Sound have assembled articles that cover a range of research and projects reflecting the confluence of the two topics. Papers describe expanded access to resources in the humanities previously unavailable, leading to a digital renaissance. This access enables data mining and new insights for research and analysis, as well as enhanced possibilities for presenting results with interactive capabilities. Case studies explore information visualization technologies used to enrich a thesis presentation, cast literary analysis in a new light and reveal associations among scholars. The advantages of visualization extend to thesaurus‐powered search interfaces but are shown to be an under‐exploited tool for music research.
Interactive visualization for multilingual search
Authors: Ruecker Stan , Shiri Ali , Fiorentino Carlos
Published: April 2012

Editor's Summary

Multilingual thesauri provide the context for exploring experimental user interfaces that support interactive visualization. The authors created two search interfaces that draw on the semantic richness of bilingual thesauri and provide for search, browse and results display. The Searchling interface offers search, browsable navigation and the full term‐record data for a selected term, as well as a simple switch between language views. It provides active user assistance by displaying options to broaden or narrow search. User evaluation showed Searchling to be easy to use, appealing broadly but especially to linear thinkers. The T‐Saurus interface is more visual, with term search results represented by the size, number, proximity and opacity of buckets. Terms can be displayed in multiple languages simultaneously, and multiple terms can be chosen to form a query to retrieve documents. Visual thinkers appreciated its dynamic and interactive visualization interface. Studies demonstrate the support both interfaces provide for fully using rich, multilingual thesauri as well as differences for users with different cognitive styles.
From records to data with viewshare: An argument, an interface, a design
Authors: Bailey Jefferson , Owens Trevor
Published: April 2012

Editor's Summary

Viewshare is a platform designed to support the work of cultural heritage institutions in their efforts to share data, dynamically visualize their collections and access and discover items. It was developed as a free and open tool for partners of the National Digital Information Infrastructure and Preservation Program. Its central goal is to reveal patterns within collections to lead to new understanding. Viewshare features a simple and intuitive interface and limited requirements for technical skills, and it supports a wide variety of digital collections and metadata types. Its users establish custom metadata, import and enhance collection data and create their own interface to support dynamic and interactive views of their digital collections. The process is illustrated with the Fulton Street Trade Card Collection from the Brooklyn Public Library.
What happens when architectural questions are not asked?
Authors: Haller Thom
Published: April 2012

Editor's Summary

A mysterious change in the background information architecture of Facebook resulted in the author apparently going silent. His disappearance was traced back to a wrong choice among the revised privacy options. The classification labels were ambiguous, not clearly differentiated, and offering no definition, leaving the user uncertain which to use. The labels All and Public were open to misinterpretation, and the distinction between two option groups was similarly vague. The example illustrates problems that arise when information architects fail to fully consider the implications of clustering certain kinds of information, the relationships between clusters and the appropriateness of labels to reflect the content. The example illustrates information architects' unending challenge to make the complex clear.
Rapid Perturbation of Free‐Energy Landscapes: From In Vitro to In Vivo
Authors: Gelman Hannah , Platkov Max , Gruebele Martin
Published: April 2012

Biological systems are often studied under the most “physiological” conditions possible. However, purposeful perturbation of biological systems can provide much information about their dynamics, robustness, and function. Such perturbations are particularly easy to apply at the interface of molecular biophysics and cellular biology, at which complex and highly regulated networks emerge from the behavior of individual biomolecules. Due to the size of diffusion coefficients and the length scale of biomolecules, the fastest timescales at this interface extend to below a microsecond. Thus perturbations must be induced and detected rapidly. We focus on examples of proteins and RNAs interacting with themselves (folding) or one another (binding, signaling). Beginning with general principles that have been learned from simple models and perturbation experiments in vitro, we progress to more complex environments that mimic aspects of the living cell, and finally rapid perturbation experiments in living cells. On the experimental side we highlight in particular two classes of rapid perturbation methods (nanoseconds to seconds) that have been traditionally employed in biophysical chemistry, but that will become increasingly important in cell biology and in vivo: fast relaxation techniques and phase‐sensitive modulation techniques. These techniques are now increasingly married with imaging to produce a spatiotemporal map of biomolecular stability, dynamics and, in the near future, interaction networks inside cells. Many important chemical processes occur on biologically fast timescales, and yet have important ramifications for slower biological networks.
Recursive partitioning analysis of prognostic factors for glioblastoma patients aged 70 years or older
Authors: Scott Jacob G. , Bauchet Luc , Fraum Tyler J. , Nayak Lakshmi , Cooper Anna R. , Chao Samuel T. , Suh John H. , Vogelbaum Michael A. , Peereboom David M. , Zouaoui Sonia , Mathieu‐Daudé Hélène , Fabbro‐Peray Pascale , Rigau Valérie , Taillandier Luc , Abrey Lauren E. , DeAngelis Lisa M. , Shih Joanna H. , Iwamoto Fabio M.
Published: April 2012

BACKGROUND:

The most‐used prognostic scheme for malignant gliomas included only patients aged 18 to 70 years. The purpose of this study was to develop a prognostic model for patients ≥70 years of age with newly diagnosed glioblastoma.

METHODS:

A total of 437 patients ≥70 years of age with newly diagnosed glioblastoma, pooled from 2 tertiary academic institutions, was identified for recursive partitioning analysis (RPA). The resulting prognostic model, based on the final pruned RPA tree, was validated using 265 glioblastoma patients ≥70 years of age from a data set independently compiled by a French consortium.

RESULTS:

RPA produced 9 terminal nodes, which were pruned to 4 prognostic subgroups with markedly different median survivals: subgroup I = patients <75.5 years of age who underwent surgical resection (9.3 months); subgroup II = patients ≥75.5 years of age who underwent surgical resection (6.4 months); subgroup III = patients with Karnofsky performance status of 70 to 100 who underwent biopsy only (4.6 months); and subgroup IV = patients with Karnofsky performance status <70 who underwent biopsy only (2.3 months). Application of this prognostic model to the French cohort also resulted in significantly different (P < .0001) median survivals for subgroups I (8.5 months), II (7.7 months), III (4.3 months), and IV (3.1 months).

CONCLUSIONS:

This model divides elderly glioblastoma patients into prognostic subgroups that can be easily implemented in both the patient care and the clinical trial settings. This purely clinical prognostic model serves as a backbone for the future incorporation of the increasing number of potential molecular prognostic markers. Cancer 2012. © 2012 American Cancer Society.
Implementation of the new American Cancer Society process for creating cancer screening guidelines
Authors: Byers Tim
Published: April 2012

The American Cancer Society recently revised the methods it will use to develop cancer screening guidelines. This commentary provides a summary of those new methods, and commentary on the roles of laboratory‐based specialists and cytologists in future screening guideline development.
Counterion‐Induced Inversion of Conformer Stability of a [5]Helquat Dication
Authors: Severa Lukáš , Jirásek Michael , Švec Pavel , Teplý Filip , Révész Ágnes , Schröder Detlef , Koval Dušan , Kašička Václav , Císařová Ivana , Šaman David
Published: April 2012

Helquats are a recently introduced class of compounds, which can be perceived as a combination of helicenes with the skeleton of bispyridinium ions such as paraquat. In addition to their helical shape, some of these compounds can also adopt saddle‐like conformations. The focus here is on a specific [5]helquat dication HQ2+, which is investigated by various experimental techniques in condensed media as well as in the gas phase in combination with parallel computational studies. For this compound, the helical form is strongly favored in the free dication HQ2+ in the gas phase as well as in the condensed‐phase salts [HQ2+ ⋅ 2X−], whereas in the singly charged ion pairs in the gas phase, the saddle conformer [SQ2+ ⋅ X−] is significantly more stable than the helical form [HQ2+ ⋅ X−] for a number of anions X−. The reason for this inversion of stability in the binary ion pairs is that the saddle conformer has a central binding pocket, in which the anion can interact with both pyridinium centers, whereas the more compact helix conformer permits the anion to approach only a single cationic center efficiently.
Metabolism and disposition of N,N‐dimethyltryptamine and harmala alkaloids after oral administration of ayahuasca
Authors: Riba Jordi , McIlhenny Ethan H. , Valle Marta , Bouso José Carlos , Barker Steven A.
Published: April 2012

Ayahuasca is an Amazonian psychotropic plant tea obtained from Banisteriopsis caapi, which contains β‐carboline alkaloids, chiefly harmine, harmaline and tetrahydroharmine. The tea usually incorporates the leaves of Psychotria viridis or Diplopterys cabrerana, which are rich in N,N‐dimethyltryptamine (DMT), a psychedelic 5‐HT2A/1A/2C agonist. The β‐carbolines reversibly inhibit monoamine‐oxidase (MAO), effectively preventing oxidative deamination of the orally labile DMT and allowing its absorption and access to the central nervous system. Despite increased use of the tea worldwide, the metabolism and excretion of DMT and the β‐carbolines has not been studied systematically in humans following ingestion of ayahuasca. In the present work, we used an analytical method involving high performance liquid chromatography (HPLC)/electrospray ionization (ESI)/selected reaction monitoring (SRM)/tandem mass spectrometry(MS/MS) to characterize the metabolism and disposition of ayahuasca alkaloids in humans. Twenty‐four‐hour urine samples were obtained from 10 healthy male volunteers following administration of an oral dose of encapsulated freeze‐dried ayahuasca (1.0 mg DMT/kg body weight). Results showed that less than 1% of the administered DMT dose was excreted unchanged. Around 50% was recovered as indole‐3‐acetic acid but also as DMT‐N‐oxide (10%) and other MAO‐independent compounds. Recovery of DMT plus metabolites reached 68%. Harmol, harmalol, and tetrahydroharmol conjugates were abundant in urine. However, recoveries of each harmala alkaloid plus its O‐demethylated metabolite varied greatly between 9 and 65%. The present results show the existence in humans of alternative metabolic routes for DMT other than biotransformation by MAO. Also that O‐demethylation plus conjugation is an important but probably not the only metabolic route for the harmala alkaloids in humans. Copyright © 2012 John Wiley & Sons, Ltd.
Paromomycin‐loaded albumin microspheres: Efficacy and stability studies
Authors: Khan Wahid , Kumar Rajendra , Singh Sukhvinder , Arora Sunil Kumar , Kumar Neeraj
Published: April 2012

In the present work, paromomycin‐loaded albumin microspheres (PM‐MS) have been formulated for passive targeting of paromomycin (PM) to macrophages, for the treatment of visceral leishmaniasis (VL). PM‐MS were prepared by spray‐drying method with a mean particle size of ≈ 3 µm. Thermal and chemical cross‐linking methods were used for controlling drug release from the prepared microspheres (MS). PM‐MS were then tested for efficacy and stability studies. In efficacy study, in vitro promastigote assay was carried out to assess the susceptibility of promastigote to PM in the concentration range of 5.0–150 µg/ml; cytotoxicity assay was performed to determine possible toxicity of PM for the host cells (peritoneal macrophages) and intracellular amastigote assay was carried out to determine the efficacy of free PM (PM solution) and encapsulated PM (PM‐MS). Results obtained indicated a significant increase in efficacy of PM‐MS in comparison to PM solution at equivalent concentration. Subsequently, stability studies of prepared formulation was carried out at various temperature and humidity conditions, these studies provided stability of formulation at all tested conditions including accelerated conditions. Thus, it can be concluded that present work provides an optimized formulation with stability and enhanced efficacy. Copyright © 2012 John Wiley & Sons, Ltd.
Trans fatty acids influence the oxidation of LDL in ECV304 cells
Authors: Zhi Tan , Yanhong Liu , Rui Liang , Jian Song , Jinping Liu , Junzhu Wu
Published: April 2012

The objectives of this study are to explore whether separate sources of trans fatty acids (TFA) have different effects on ECV304 cell line and to further elucidate the oxidation mechanism induced by TFA. ECV304 cells are used in the study because they display many endothelial features. Cell apoptosis rates increased in a dose‐dependent manner following 24‐h treatment with TFA from separate sources. Additionally, TFA stimulated human alpha‐defensin 1 (HNP‐1) expression and resulted in a significant increase in both malondialdehyde (MDA) and ROS levels. MDA levels reach their peak at 18 h. HNP‐1 expression levels increase at 2 h and then reach their peak at 10 h. At the same time, the protein carbonyl (PCO) value declines slightly. After 10 h of TFA co‐culture, the cells were washed and fresh low‐density lipoprotein (LDL) was added. MDA generation significantly increased after 6 h and it could be inhibited by 4‐aminobenzoic acid hydrazide (ABAH) or sodium ferulate. However, after the TFA co‐culture for 2 h, adding LDL for 6 h just caused slight MDA generation change and the MDA generation could be inhibited by verapamil or sodium ferulate. TFA from different sources did not have different effects on ECV304. HNP‐1 mediates the oxidation induced by TFA by activating ROS. Furthermore, TFA can stimulate the oxidation of LDL in ECV304 cells through both passive and active pathway. In the oxidation induced by linoelaidic acid, ABAH can decrease the MDA generation in active oxidation pathway and verapamil can decrease the MDA generation in passive oxidation pathway.
Simulation and Experiment of a Cogeneration System Based on Proton Exchange Membrane Fuel Cell
Authors: Hwang J.‐J. , Wang P.‐C. , Kuo J.‐K.
Published: April 2012

This project designs and simulates a cogeneration system of proton exchange membrane fuel cell using Matlab/Simulink software and Thermolib heat module components. The system not only satisfies the need for electric power, but also provides heat recovery for future uses, thus increasing energy transfer efficiency.

PEM fuel cell‐based cogeneration system is introduced, including the hydrogen supply subsystem, air supply subsystem, load control subsystem, real‐time monitoring block, and heat recovery subsystem. The complete fuel cell‐based cogeneration system is constructed by assembling the fuel cell stack, fuel, coolant flow rate control system, and all the subsystems.

In addition to the fuel cell experiment, influencing factors on the fuel cell‐based system, such as the fuel inhale rate, coolant flow rate, system temperature, fuel humidification, thermal efficiency, electrical efficiency, and combined heat and power (CHP) system efficiency, are analyzed and charted regarding different loads. In this system, with the power at 3 kW, the CHP efficiency reaches 64%. The CHP efficiency is 76.6% with the load power at 4 kW. When the power is at 5 kW, the thermal efficiency reaches 36.9% and the CHP efficiency reaches 82.9%.
Regression of cardiac hypertrophy in cyp1a1ren‐2 transgenic rats
Authors: Peters Barbara S. , Dornaika Rami , Hosten Norbert , Hadlich Stefan , Mullins John J. , Peters Jörg , Rettig Rainer
Published: April 2012

Purpose:

To evaluate the usefulness of the cyp1a1ren‐2 transgenic rat model of inducible hypertension for studies of the development and regression of cardiac hypertrophy.

Materials and Methods:

Cyp1a1ren‐2 rats received a diet containing 0% or 0.167% indole‐3‐carbinonl (I3C) for 4 weeks to induce hypertension. Cardiac magnetic resonance imaging (MRI) at 7 T was performed every second week for 10 weeks to measure left ventricular mass and the ejection fraction. Concomitantly, in six cyp1a1ren‐2 rats blood pressure was recorded telemetrically.

Results:

Plasma prorenin concentrations rose from 138 ± 38 to 15,490 ± 3990 ng/angiotensin I/mL/h (P < 0.001) in I3C‐treated transgenic rats and returned to basal levels after cessation of I3C. Mean blood pressure increased to a plateau of 169 ± 11 mmHg by the second week of induction. After cessation of I3C (day 28), arterial pressure dropped to values slightly below those prior to induction within 4 days (basal: 106 ± 7 mmHg, day 32: 103 ± 21 mmHg; NS). At day 28, left ventricular mass was increased by 39% vs. 4% in controls (P < 0.001) without changes of the ejection fraction. Cardiac hypertrophy was completely reversed at day 70, as evaluated by MRI.

Conclusion:

The cyp1a1ren‐2 transgenic rat is a useful model to study reversal and healing in the absence of surgical interventions. J. Magn. Reson. Imaging 2012;36:373–378. © 2012 Wiley Periodicals, Inc.
Meta‐analysis of the association between the interleukin‐1A −889C/T polymorphism and Alzheimer's disease
Authors: Hua Ye , Zhao Hui , Kong Yuenan , Lu Xiaojie
Published: April 2012

No clear consensus has been reached on the Interleukin‐1A (IL‐1A) −889C/T polymorphism and Alzheimer's disease (AD) risk. In this meta‐analysis, 27 case–control studies were assessed to evaluate the possible association. Overall, positive associations of the IL‐1A −889C/T polymorphism with AD risk were found in allele comparison T vs. C (OR = 1.09, 95% CI = 1.01–1.18), recessive model TT vs. CT + CC (OR = 1.21, 95% CI = 1.01–1.45), and homozygote comparison (TT vs. CC; OR = 1.32, 95% CI = 1.04–1.67). In subgroup analysis stratified by ethnicity, significant associations were demonstrated in Caucasians but not in Asians. In subgroup analysis according to the age of onset, the data showed a significant association in patients with late‐onset AD in Caucasians but not in early‐onset AD. In conclusion, this meta‐analysis supports the idea that IL‐1A –889C/T polymorphism is capable of causing AD and LOAD susceptibility in Caucasians but not in Asians. © 2012 Wiley Periodicals, Inc.
Liquid–Liquid Extraction of 3FOx and 5FOx Polyoxetane Diols: Impact on Polyurethane Mechanical Properties, Surface Morphology, and Wetting Behavior
Authors: Zhang Wei , Henke Daniel , Presnall David , Chakrabarty Souvik , Wang Chenyu , Wynne Kenneth J.
Published: April 2012

Laboratory prepared and commercial poly(2‐2,2,2‐trifluoroethoxy‐2‐methyl)oxetane, P[3FOx] and poly(2‐2,2,2‐pentafluoropropoxy‐2‐methyl)oxetane, P[5FOx] polyols contain varying amounts of cyclics and low molar mass (LMW) constituents as byproducts of ring opening polymerization. Guided by phase diagrams determined by cloud point measurements, P[3FOx] diol separation is achieved. The impact of purification is explored via the preparation of P[3FOx] and P[5FOx] polyurethanes from cyclic/LMW‐free diols. Mechanical properties are improved because of higher polyurethane molecular weights. AFM revealed complex rugosity that is correlated with dynamic contact angles free from effects of water contamination.
Stabilization of pH‐Sensitive mPEG–PH–PLA Nanoparticles by Stereocomplexation Between Enantiomeric Polylactides
Authors: Liu Rong , He Bin , Li Dong , Lai Yusi , Tang James. Z. , Gu Zhongwei
Published: April 2012

Methoxy poly(ethylene glycol)–poly(L‐histidine)–poly(lactide) (mPEG45–PH30–PLA82) triblock copolymers self‐assemble into nanoparticles by sterocomplexation. The properties of the stereocomplex nanoparticles including morphology, stability, and biocompatibility are investigated. The results reveal that the stereocomplexation between PLLA and PDLA segments could prevent the aggregation of the nanoparticles when the pH value is around 6.8. The mean diameter of the stereocomplex nanoparticles is stabilized at about 100 nm when the pH values are changed from 7.9 to 5.0. The cytotoxicity of the stereocomplex nanoparticles is evaluated, and the results demonstrate that the stereocomplexation could decrease the cytotoxicity of the PDLA segments.
The importance of RF bandwidth for effective tagging in pulsed arterial spin labeling MRI at 9.4T
Authors: Wells J. A. , Siow B. , Lythgoe M. F. , Thomas D. L.
Published: April 2012

The movement towards MRI at higher field strengths (>7T) has enhanced the appeal of arterial spin labeling (ASL) for many applications due to improved SNR of the measurements. Greater field strength also introduces increased magnetic susceptibility effects resulting in marked B0 field inhomogeneity. Although B0 field perturbations can be minimised by shimming over the imaging volume, marked field inhomogeneity is likely to remain within the labeling region for pulsed ASL (PASL). This study highlights a potential source of error in cerebral blood flow quantification using PASL at high field. We show that labeling efficiency in flow‐sensitive alternating inversion recovery (FAIR) displayed marked sensitivity to the RF bandwidth of the inversion pulse in a rat model at 9.4T. The majority of preclinical PASL studies have not reported the bandwidth of the inversion pulse. We show that a high bandwidth pulse of > = 15 kHz was required to robustly overcome the field inhomogeneity in the labeling region at high field strength, which is significantly greater than the inversion bandwidth ~2–3 kHz used in previous studies. Unless SAR levels are at their limit, we suggest the use of a high bandwidth labeling pulse for most PASL studies. Copyright © 2012 John Wiley & Sons, Ltd.
Glacier-dammed Lake in Southeastern Tibetan Plateau during the Last Glacial Maximum
Authors: Guangxiang Yuan , Qingli Zeng
Published: April 2012

Lacustrine, alluvial terraces and sediments record at least one Holocene glacially dammed lake in Songzong Basin immediately upstream of the Purlung TsangpoRiver, a main tributary of the downstream of Yarlung Tsangpo River, at the northeastern syntaxis of the Himalaya. The lacustrine deposit is more than 88 meters thick at the SongzongLandslide. There is an 18.33 meters thick layer of lacustrine silt within the lacustrine terrace. The Optical Simulated Luminescence (OSL) ages at the bottom and top of the lacustrine silt layerare 22.5±3.3ka B.P., and 16.1±1.7ka B.P., respectively, which indicates that the lacustrine deposits were formed during the Last Glacial Maximum ranging from 25kaB.P. to 15kaB.P.The ancient shorelines and the lake erosion zone confirm the preexistence of Songzong Lake. There are also terraces formed by moraines in the Songzong Basin. The high and large moraineterrace seen near the mouth of the Dongqu Valley is very prominent. The special characteristics of thelacustrine sediment and the ancient lake line in the Songzong Basin indicate that the lacustrinesediments are related to the blocking of the Purlung Tsangpo River by a glacier from DongquValley during Last Glacial Maximum.
Geochemistry of Hindoli Group Metasediments, SE Aravalli Craton, NW India: Implications for Palaeoweathering and Provenance
Authors: Saxena Asha , Pandit M. K.
Published: April 2012

The southeastern fringe of the Precambrian Aravalli fold belt has been designated as Jahazpur Belt, which includes two greenschist facies metasedimentary lithopackages, Hindoli (Late Archean/Paleoproterozoic) and Jahazpur (Paleoproterozoic) Groups. We present geochemical data on metapelite (phyllite) and metagreywackes from the Hindoli Group. Metapelites are enriched in alumina while metagreywackes show a wide range and higher abundance of silica. Covariance between TiO2 – Al2O3, K2O – Al2O3 pairs and moderate to high SiO2/MgO ratios indicate a strong weathering control. Chemical Index of Alteration (CIA = 68 for metagraywackes; 75 for metapelites) reveals moderately weathered protoliths for them. Fractionated LREE pattern with almost flat HREE trend and moderate to high Eu anomalies (Eu/Eu* = 0.66 to 0.8) indicate feldspar bearing granite - granodiorite as probable compositions in the provenance. Very high PIA values (93) for metapelites reflect almost complete feldspar dissolution while the corresponding values for metagraywackes (68) are relatively lower. The diagnostic immobile trace elements (Sc, Zr, Th) can be interpreted as a variable felsic source (mainly granitic and subordinate granodioritic) for metagreywackes and a granodioritic (more mafic) one for metapelites. Considering the broad Precambrian geological set-up of NW India, the Banded Gneiss Complex (BGC), which predominantly comprises TTG gneisses and granites, amphibolite, etc. seems to be the most likely provenance for Hindoli sediments.
Childhood trauma and distress experiences associate with psychotic symptoms in patients attending primary and psychiatric outpatient care. Results of the RADEP study
Authors: Luutonen S. , Tikka M. , Karlsson H. , Salokangas R.K.R.
Published: April 2012

Goal

We studied the prevalence of and association between psychotic symptoms and childhood trauma experiences in primary care patients compared with psychiatric care patients.

Patients and methods

We note 911 primary care and psychiatric care patients over 16 years of age filled in a questionnaire including a list of lifetime psychotic symptoms of the Composite International Diagnostic Interview (CIDI) and the childhood Trauma and Distress Scale (TADS). Prevalence of and correlations between psychotic symptoms and childhood trauma and stressful experiences were calculated. Association between the sum of CIDI symptoms and the TADS sum score was analysed by Anova.

Results

In primary care, more than half of the patients had had at least one psychotic symptom during their lifetime, and nearly 70% of patients had experienced a childhood trauma at some time or more often. In psychiatric care patients, CIDI symptoms were more prevalent and TADS scores were higher than in primary care patients. In the whole sample, CIDI symptoms correlated with TADS scores. The association remained even when the effects of age, service, and patient's functioning were taken into account. There was a dose-response between TADS scores and CIDI symptoms.

Conclusion

Childhood trauma experiences associate with psychotic symptoms. In clinical work, it is important to acknowledge that psychotic symptoms and childhood trauma experiences are common not only in psychiatric care but also in primary care patients, and thus require adequate attention.
Sonographic Evaluation of Supraspinatus Cross‐sectional Area in Collegiate Baseball Players
Authors: Malanga Gerard A. , Chu Samuel K. , Ramirez Del Toro Jose , Karnaugh Ronald D. , Dentico Richard , Komaroff Eugene
Published: April 2012

Objective

To establish the normal thickness of the supraspinatus tendon in collegiate baseball players with the use of ultrasound and to determine whether there are any significant differences between the dominant and nondominant supraspinatus thickness.

Design

A cross‐sectional observational study.

Setting

An outpatient clinical setting.

Participants

Twelve healthy, asymptomatic collegiate pitchers between the ages of 19 and 22 years.

Methods

Sonographic evaluation of 12 asymptomatic pitchers (9 right‐hand dominant and 3 left‐hand dominant) between the ages of 19 and 22 years was performed in a transverse plane (short axis) and longitudinal view (long axis) of their right and left shoulders. Maximum thickness was measured in both the long‐ and short‐axis views. On the long‐axis view, measurement was taken at the point where there was maximal height observed at the footprint insertion. Mixed‐model analysis of variance was used to test for differences in tendon thickness across factors. Post hoc contrasts were performed with a Tukey adjustment for the P values. The mean ± SD values, side‐to‐side difference, and difference between dominant and nondominant values were calculated and statistically analyzed for differences.

Results

An ultrasound examination showed a significant 3‐way interaction (P = .038) for view by side of hand dominance. Post hoc contrasts revealed that supraspinatus tendon thickness for right‐handed pitchers in the long‐axis view on the right side showed a mean value of 8.0 ± 0.32 mm versus the long‐axis view on the left side of 6.5 ± 0.34 mm (P = .006) and the short‐axis view on the right of 7.4 ± 0.40 mm versus the short‐axis view on the left of 6.1 ± 0.26 mm (P = .036). Supraspinatus tendon thickness for left‐handed pitchers in the long‐axis view on the left side showed a mean value of 7.5 ± 0.59 mm versus the long‐axis view on the right side of 5.9 ± 0.56 mm (P = .137) and the short‐axis view on the left of 6.5 ± 0.45 mm versus the short‐axis view on the right of 6.5 ± 0.68 mm (P = .999).

Conclusions

A database of normal values for supraspinatus tendon thickness in collegiate baseball pitchers has been developed. The results are consistent with expectations when the dominant side is compared with the nondominant side for right‐handed pitchers with increased tendon thickness noted on the dominant side. There was no side‐to‐side difference found in left‐hand dominant pitchers.
Genomic regions affecting fitness of the sweet corn mutantsugary1
Authors: DJEMEL A. , ROMAY M. C. , REVILLA P. , KHELIFI L. , ORDÁS A. , ORDÁS B.
Published: April 2012

Mutants often reduce fitness when incorporated into some genotypes, as is the case of the mutant genesugary1(su1) in maize (Zea maysL.). Understanding the genetic factors affecting variation in the fitness of a mutant is of major interest from a theoretical point of view and also from a breeder's perspective. The genetic regulation ofsu1behaviour was examined in two independent materials. First, populations of two recombinant inbred lines (RIL) were used, belonging to the Nested Association Mapping (NAM) design produced from crosses between the maize inbred B73 and two sweet corn lines (P39 and Il14h) that were genotyped with 1106 single nucleotide polymorphisms (SNPs). These RILs had a group of lines with thesu1allele and another group with the wild allele. At each marker, the allele frequencies of both groups of RILs were compared. Second, an F2population derived from the cross between A619 (a field maize inbred line) and P39 (a sweet corn inbred line) was characterized with 295 simple sequence repeats (SSRs). In addition, the population was phenotyped for several traits related to viability. A large linkage block was detected aroundsu1in the RILs belonging to the NAM. Furthermore, significant genomic regions associated withsu1fitness were detected along the 10 maize chromosomes, although the detected effects were small. Quantitative trait loci (QTLs) with effects in multiple traits related tosu1fitness were detected in the F2population, for example at bin 5·04. Therefore, the present results suggest that thesu1fitness depends on many genes of small effect distributed along the genome, with pleiotropic effects on multiple traits.