bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and identification of transfer factor specific to Staphylococcus aureus in vitro
Authors: Zhou Jianwei , Kong Cui , Wang Xiukui , Shao Jun , Feng Lin , Zhang Zhaocai
Published: May 2014

The objective of the study was to explore the methods for preparing transfer factor specific to Staphylococcus aureus (SA‐STF) in vitro. Under the optimum conditions, the spleen cells of rabbits were immunized with SA in vitro to prepare SA‐STF, and the immune activities were identified with the phagocytosis and sterilization, skin delayed‐type hypersensitivity, and immune protection tests. The concentration of polypeptide was 2.26 ± 0.27 mg/mL, and ribose was 0.684 ± 0.094 mg/mL. The phagocytosis and sterilization rates of the STF group were 70.9 ± 12.4% and 62.1 ± 12.2%, respectively, and compared with the non‐specific transfer factor (NTF) group, there were no significant differences (P = 0.074 and 0.069, respectively). The skin was inflamed and marked nodules formed at the injection site in the mice of the STF group rather than the NTF and control groups. The survival rate of the STF‐1 group was significantly higher than the survival rates of the STF‐2 (P = 0.024) and NTF groups (P = 0.016). SA‐STF was prepared and characterized successfully in vitro, and it probably is a biological candidate for therapy or adjuvant therapy for diseases caused by Staphylococcus aureus.
Overexpression of microRNAs enhances recombinant protein production in Chinese hamster ovary cells
Authors: Loh Wan Ping , Loo Bernard , Zhou Lihan , Zhang Peiqing , Lee Dong‐Yup , Yang Yuansheng , Lam Kong Peng
Published: May 2014

MicroRNAs (miRNAs) are short, non‐coding RNAs that can negatively regulate expression of multiple genes at post‐transcriptional levels. Using miRNAs to target multiple genes and pathways is a promising cell‐engineering strategy to increase recombinant protein production in mammalian cells. Here, we identified miRs‐17, ‐19b, ‐20a, and ‐92a to be differentially expressed between high‐ and low‐ monoclonal antibody‐producing Chinese hamster ovary (CHO) cell clones using next‐generation sequencing and quantitative real‐time PCR. These miRNAs were stably overexpressed individually and in combination in a high‐producing clone to assess their effects on CHO cell growth, recombinant protein productivity and product quality. Stably transfected pools demonstrated 24–34% increases in specific productivity (qP) and 21–31% increases in titer relative to the parental clone, without significant alterations in proliferation rates. The highest protein‐producing clones isolated from these pools exhibited 130–140% increases in qP and titer compared to the parental clone, without major changes in product aggregation and N‐glycosylation profile. From our clonal data, correlations between enhanced qP/titer and increased levels of miRs‐17, ‐19b, and ‐92a were observed. Our results demonstrate the potential of miRs‐17, ‐19b, and ‐92a as cell‐engineering targets to increase recombinant protein production in mammalian cells.
Cancer incidence in Khartoum, Sudan: first results from the Cancer Registry, 2009–2010
Authors: Saeed Intisar E. , Weng Hsin‐Yi , Mohamed Kamal H. , Mohammed Sulma I.
Published: May 2014

In 2009, the first National Population‐based Cancer Registry (NCR) was established in Sudan. We report in this study, the first data from the NCR for Khartoum State for the period 2009–2010. The NCR staff used passive and active approaches to collect data on cancer diagnosed by all means in Khartoum State. Rates were age standardized to the 2010 Sudan Standard Population and 1966 and 2000 World Standard Population and expressed per 100,000 populations. During 2009–2010, 6771 new cancer cases were registered. Of those, 3646 (53.8%) cases were in women and 3125 (46.2%) were in men. The most commonly diagnosed cancer among women was breast followed by leukemia, cervix, and ovary, and among men it was prostate cancer followed by leukemia, lymphoma, oral, colorectal, and liver. In children less than 15 years of age, leukemia was the most common cancer followed lymphoma, and cancer of the eye, bone, kidney, and the brain. The overall age‐standardized rate (ASR) per 100,000 population was higher in women (124.3) than in men (90.8) using 2010 Sudan Standard Population. Similarly, it was higher in women (188.6 and 206.3 per 100,000 population) than in men (145.4 and 160.0 per 100,000 population) using 1966 and 2000 World Standard Population, respectively. The data from NCR indicated that prostate and breast as the most commonly diagnosed cancer sites in men and women in Khartoum, while cancer of the cervix trailed behind portraying a cancer picture similar to that of the developed world. Despite the study limitations, the NCR data gave a fair representation of cancer profile of Khartoum State and underscored the need for high‐quality cancer registries in Sudan.
Highly Efficient Reversible Hydrogenation of Carbon Dioxide to Formates Using a Ruthenium PNP‐Pincer Catalyst
Authors: Filonenko Georgy A. , van Putten Robbert , Schulpen Erik N. , Hensen Emiel J. M. , Pidko Evgeny A.
Published: May 2014

The front cover artwork for Issue 6/2014 is provided by the research group of Inorganic Materials Chemistry and the Institute for Complex Molecular Systems, Eindhoven University of Technology (The Netherlands). The image shows a concept of a hydrogen battery in which H2 storage and its release are achieved through reversible hydrogenation of CO2 catalysed by an Ru‐PNP pincer complex. See the Communication itself at http://dx.doi.org/10.1002/cctc.201402119.
Probing the Redox Chemistry of Titanium Silicalite‐1: Formation of Tetrahedral Ti3+ Centers by Reaction with Triethylaluminum
Authors: Morra Elena , Giamello Elio , Chiesa Mario
Published: May 2014

Transition‐metal ions with open‐shell configurations hold promise in the development of novel coordination chemistry and potentially unprecedented redox catalysis. Framework‐substituted Ti3+ ions with tetrahedral coordination are generated by reductive activation of titanium silicalite‐1 with triethylaluminum, an indispensable co‐catalyst for heterogeneous Ziegler–Natta polymerization catalysts. Continuous‐wave and pulse electron paramagnetic resonance methods are applied to unravel details on the local environment of the reduced transition metal‐ions, which are shown to be part of the silica framework by detection of 29Si hyperfine interactions. The chemical accessibility of the reduced sites is probed using ammonia as probe molecule. Evidence is found for the coordination of a single ammonia molecule. Comparison to similar systems, such as TiAlPO‐5, reveals clear differences in the coordination chemistry of the reduced Ti sites in the two solids, which may be understood considering the different electronic properties of the solid frameworks.
Size‐Regulable Vesicles Based on Anion–π Interactions
Authors: He Qing , Han Yuchun , Wang Yilin , Huang Zhi‐Tang , Wang De‐Xian
Published: May 2014

Taking tetraoxacalix[2]arene[2]triazine as a functionalization platform, a series of new amphiphilic molecules were synthesized in 18 to 53 % yields by using a fragment coupling protocol. These amphiphilic molecules self‐assembled into stable vesicles in a mixture of THF and water, with the surface of the vesicles engineered by electron‐deficient cavities. Various anions are able to selectively influence the size of self‐assembled vesicles, following the order of F−<ClO4−<SCN−<BF4−<Br−<Cl−<NO3−, as revealed by DLS measurements. Such a sequence was independent with the hydration cost and in agreement with the binding strength of anions with tetraoxacalix[2]arene[2]triazine host molecule, indicating that the anion–π interaction most probably competed over other possible weak interactions and accounted for this interesting selectivity. In addition, the chloride permeation process across the membrane of the vesicles was also preliminarily studied by means of fluorescent experiments. This study, in addition to providing the potentiality of heteracalixaromatics as new models to construct functional vesicles, opens a new avenue to study the anion–π interactions in aqueous and also potentially in living systems.
Interfacial Chiral Selection by Bulk Species
Authors: Dong Hua , Ignés‐Mullol Jordi , Claret Josep , Pérez Lourdes , Pinazo Aurora , Sagués Francesc
Published: May 2014

A chiral selection process in a self‐assembled soft monolayer of an achiral amphiphile as a consequence of its interaction with chiral species dissolved in the aqueous subphase, is reported. The extent of the chiral selection is statistically measured in terms of the enantiomorphic excess of self‐assembled submillimeter domains endowed with well‐defined orientational chirality that is unambiguously resolved using optical microscopy. Our results show that the emergence of chirality is mediated by electrostatic interactions and significantly enhanced by hydrophobic effects. This chiral chemical effect can be suppressed and even reversed by opposing a macroscopic physical influence, such as vortical stirring. This result gives evidence for the crucial role of hydrodynamic effects in supramolecular aggregation.
A Highly Luminescent Tetramer from a Weakly Emitting Monomer: Acid‐ and Redox‐Controlled Multiple Complexation by Cucurbit[7]uril
Authors: Bergamini Giacomo , Fermi Andrea , Marchini Marianna , Locritani Mirko , Credi Alberto , Venturi Margherita , Negri Fabrizia , Ceroni Paola , Baroncini Massimo
Published: May 2014

The tetrahedral, shape‐persistent molecule 14+, containing four pyridylpyridinium units connected through a central carbon atom, exhibits unexpected photophysical properties including a substantially redshifted absorption (2350 cm−1) and a very strong fluorescence (Φem=40 %), compared with the monomer 2+ (Φem=0.4 %). Density functional theory calculations on the structure and spectroscopic properties of 14+ and 2+ show that exciton interactions, homoconjugation, and orbital nature account for the observed differences in their photophysical properties. The protonated tetramer binds four cucurbit[7]uril molecules and the host/guest interactions can be controlled by chemical (acid/base) as well as redox stimuli.
Reductive Cross‐Coupling Reactions between Two Electrophiles
Authors: Knappke Christiane E. I. , Grupe Sabine , Gärtner Dominik , Corpet Martin , Gosmini Corinne , Jacobi von Wangelin Axel
Published: May 2014

Reductive cross‐electrophile coupling reactions have recently been developed to a versatile and sustainable synthetic tool for selective CC bond formation. The employment of cheap and abundant electrophiles avoids the pre‐formation and handling of organometallic reagents. In situ reductive coupling is effected in the presence of a transition‐metal catalyst (Ni, Co, Pd, Fe) and a suitable metallic reductant (Mn, Zn, Mg). This Concept article assesses the current state of the art and summarizes recent protocols with various combinations of alkyl, alkenyl, allyl, and aryl reagents and highlights key mechanistic studies.
Nickel‐Catalyzed Decarboxylative Acylation of Heteroarenes by sp2 CH Functionalization
Authors: Yang Ke , Zhang Cheng , Wang Peng , Zhang Yan , Ge Haibo
Published: May 2014

Nickel‐catalyzed ligand‐free decarboxylative cross‐coupling of azole derivatives with α‐oxoglyoxylic acids has been developed. This work represents the first example of decarboxylative cross‐coupling reactions, in a CH bond functionalization manner, through nickel catalysis, and tolerates various functional groups. Additionally, this approach provides an efficient access to azole ketones, an important structural motif in many medicinal compounds with a broad range of biological activities.
Enantioselective Synthesis of Xanthatin
Authors: Bergmann Andreas , Reiser Oliver
Published: May 2014

The enantioselective synthesis of cytostatic and antibiotic xanthatin (1 a) is reported. As a key intermediate, a bicyclic compound 2 was identified, which can be readily synthesized from methyl‐2‐furoic acid in diastereo‐ and enantiomerically pure form. Compound 2 can be functionalized regio‐ and stereoselectively at C‐6 and C‐7, allowing the facile introduction of the functionalities found in xanthatin, as well as the synthesis of derivatives thereof. Moreover, a robust strategy for the introduction of the exo‐methylene group at C‐3, commonly found in many sesquiterpenes, was developed that makes use of masking the alkene in the α,β‐unsaturated carbonyl system by O‐pivaoyl, which is stable under acidic and mild basic conditions but eliminated upon treatment with strong bases.
Redox‐ and Hypoxia‐Responsive MRI Contrast Agents
Authors: Do Quyen N. , Ratnakar James S. , Kovács Zoltán , Sherry A. Dean
Published: May 2014

The development of responsive or “smart” magnetic resonance imaging (MRI) contrast agents that can report specific biomarker or biological events has been the focus of MRI contrast agent research over the past 20 years. Among various biological hallmarks of interest, tissue redox and hypoxia are particularly important owing to their roles in disease states and metabolic consequences. Herein we review the development of redox‐/hypoxia‐sensitive T1 shortening and paramagnetic chemical exchange saturation transfer (PARACEST) MRI contrast agents. Traditionally, the relaxivity of redox‐sensitive Gd3+‐based complexes is modulated through changes in the ligand structure or molecular rotation, while PARACEST sensors exploit the sensitivity of the metal‐bound water exchange rate to electronic effects of the ligand‐pendant arms and alterations in the coordination geometry. Newer designs involve complexes of redox‐active metal ions in which the oxidation states have different magnetic properties. The challenges of translating redox‐ and hypoxia‐sensitive agents in vivo are also addressed.
Inferior survival among Aboriginal children with cancer in Ontario
Authors: Marjerrison Stacey , Pole Jason D. , Sung Lillian
Published: May 2014

BACKGROUND

Pediatric cancer distribution and outcomes have not been examined in Canadian Aboriginal children. The objective of this study was to describe the distribution, event‐free survival, and overall survival of Aboriginal children with malignancies who reside in Ontario compared with non‐Aboriginal children.

METHODS

This population‐based study included 10,520 Ontario children (aged <18 years) who were diagnosed with cancer between 1985 and 2011. Patients were identified from the Pediatric Oncology Group of Ontario Networked Information System database. Aboriginal children were identified by self‐reported ethnicity or postal code on a Native reserve at diagnosis. Descriptive statistics of the patients were presented and compared using the Fisher exact test. Event‐free and overall survival probabilities were calculated for Aboriginal and non‐Aboriginal children, described using Kaplan‐Meier curves, and compared using log‐rank tests.

RESULTS

In total, 65 Aboriginal children and 10,364 non‐Aboriginal children with malignancy were identified. The distribution of malignancy type was similar between the 2 groups. There were no significant differences in baseline characteristics, presence of metastatic disease, or treatment approach (clinical trial, standard of care, or individualized protocol) between the groups. The 5e‐year event‐free survival rate (± standard error) was 56.3% ± 6.2% among Aboriginal children versus 72.8% ± 0.4% among non‐Aboriginal children (P = .0042), and the 5‐year overall survival rate was 64% ± 6.0% versus 79.3 ± 0.4% (P = .0017), respectively. The cause of death did not vary according to Aboriginal ethnicity.

CONCLUSIONS

Survival was significantly inferior among Aboriginal children who had cancer compared with non‐Aboriginal children who had cancer in Ontario. Future studies are required to define the etiology of this disparity, evaluate the issue nationally, and create interventions to improve outcomes for Aboriginal children. Cancer 2014;120:2751–2759. © 2014 American Cancer Society.
Infections among long‐term survivors of childhood and adolescent cancer: A report from the Childhood Cancer Survivor Study
Authors: Perkins Joanna L. , Chen Yan , Harris Anne , Diller Lisa , Stovall Marilyn , Armstrong Gregory T. , Yasui Yutaka , Robison Leslie L. , Sklar Charles A. ,   on behalf of the Childhood Cancer Survivor Study
Published: May 2014

BACKGROUND

Little is known about infections among adult survivors of childhood cancer. The authors report the occurrence of infections and risk factors for infections in a large cohort of survivors of childhood cancer.

METHODS

The Childhood Cancer Survivor Study cohort was used to compare incidence rates of infections among 12,360 5‐year survivors of childhood cancer with the rates of 4023 siblings. Infection‐related mortality of survivors was compared with that of the US population. Demographic and treatment variables were analyzed using Poisson regression to determine the rate ratios (RRs) and corresponding 95% confidence intervals (CIs) for associations with infectious complications.

RESULTS

Compared with the US population, survivors were at an increased risk of death from infectious causes (standardized mortality ratio [SMR], 4.2; 95% CI, 3.2‐5.4), with the greatest risk observed among females (SMR, 3.2; 95% CI, 1.5‐6.9) and among those who had been exposed to total body irradiation (SMR, 7.8; 95% CI, 1.8‐33.0). Survivors also reported higher rates than siblings of overall infectious complications (RR, 1.3; 95% CI, 1.2‐1.4) and higher rates of all categories of infection.

CONCLUSIONS

Survivors of childhood cancer remain at elevated risk for developing infectious‐related complications, and they have a higher risk of infection‐related mortality years after therapy. Further investigation is needed to provide insight into the mechanisms for the observed excess risks. Cancer 2014;120:2514–2521. © 2014 American Cancer Society.
Accuracy of bronchial brush and wash specimens prepared by the ThinPrep method in the diagnosis of pulmonary small cell carcinoma
Authors: Wang Cheng , Duan Qiuli , Kelly Margaret , Duggan Máire A.
Published: May 2014

BACKGROUND

ThinPrep bronchial brush and wash accuracy in the diagnosis of pulmonary small cell carcinoma (pSCCa) and measured as sensitivity, specificity, positive and negative predictive values (PPV and NPV) is incompletely studied or unknown.

METHODS

Specimens collected over 5 years from 199 pSCCa and 938 negative (Neg) for pulmonary cancer individuals were selected by linking the laboratory file with the cancer registry. Results other than unsatisfactory were classified as true‐positive and ‐negative, and false‐positive and ‐negative tests so as to calculate accuracy estimates. Slides of all false‐negative and ‐positive and randomly selected samples of true‐positive and ‐negative tests were evaluated for 11 abnormal cell features typical of pSCCa in conventional preparations: distribution differences by disease status were tested for significance.

RESULTS

There were 129 brush and 170 wash in the pSCCa group and 365 brush and 1153 wash in the Neg group. Of all specimens, 1.2% were unsatisfactory. Brush sensitivity, specificity, PPV, and NPV were 61.9%, 99.4%, 97.5%, and 88%, respectively. Wash frequencies were 53.3%, 98.8%, 86.5%, and 93.5%, respectively. Abnormal cell features occurred in 29.9% of the selected pSCCa and 4.7% of the Neg specimens, and distribution differences were significant for each feature (P < .001).

CONCLUSIONS

Unsatisfactory brush and wash specimens are infrequent in the diagnosis of pSCCa, and both have moderate sensitivity and high specificity, PPV, and NPV. pSCCa abnormal cell features resemble those seen in conventional preparations and can distinguish specimens with pSCCa from those negative for pulmonary cancer. Cancer (Cancer Cytopathol) 2014;122:577–585. © 2014 American Cancer Society.
Does hue affect the perception of grayness?
Authors: Shamey Renzo , Sawatwarakul Weethima , Fu Sha
Published: May 2014

Although gray is defined as an achromatic color sensation varying only in lightness, in practice, grayness can be tinged by any hue within a limited range of chroma. Given the fact that preferred perceived white and black are slightly chromatic, the hypothesis tested in this study is that the preferred perceived object gray is also slightly chromatic. Two psychophysical experiments were carried out to test this hypothesis. A total of 56 color normal subjects assessed 27 different gray patches that varied mainly in hue, in three separate trials. Subjects selected a subset of samples (10 in the first experiment and five in the second experiment) that were considered “most gray” resulting in 168 selected sets of samples. Subjects then ranked their selected subset of samples from most to least gray. A total of 1225 assessments were thus obtained (750 assessments in the first experiment and 465 in the second experiment). Results from both experiments were in good agreement and indicate that greenish blue grays in the range of 190° to 235° of CIELAB hue angle were selected as most gray, thus indicating that the perception of grayness is influenced by hue. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 374–382, 2015
Population pharmacokinetic and pharmacodynamic analysis of plasma Aβ40 and Aβ42 following single oral doses of the BACE1 inhibitor AZD3839 to healthy volunteers
Authors: Quartino Angelica , Huledal Gunilla , Sparve Erik , Lüttgen Maria , Bueters Tjerk , Karlsson Pär , Olsson Tina , Paraskos Jonathan , Maltby Justine , Claeson‐Bohnstedt Kristina , Lee Chi‐Ming , Alexander Robert , Fälting Johanna , Paulsson Björn
Published: May 2014

Modulating deposition of Aβ‐containing plaques in the brain may be beneficial in treating Alzheimer's disease. β‐site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitors have been shown to reduce Aβ in plasma and CSF in healthy volunteers. In this study safety, pharmacokinetics and pharmacodynamics that is reduction of the plasma biomarkers Aβ40 and Aβ42, of the BACE1 inhibitor AZD3839 were evaluated.

Single oral ascending doses (1–300 mg) of AZD3839 were administered to 54 young healthy volunteers in a randomized, double‐blind, placebo‐controlled study. The data was analyzed using non‐linear mixed effects modeling. AZD3839 reduced Aβ40 and Aβ42 in plasma with estimated potencies (EC50) of 46 and 59 nM, respectively, and a maximum effect of approximately 55%. This was in excellent agreement with the concentration–response relationships obtained in mouse and guinea pig. AZD3839 exposure displayed non‐linear kinetics, described by a three‐compartment model with a saturated binding compartment and an increase in bioavailability with dose. AZD3839 was safe, although, a dose‐dependent QTcF prolongation was observed (mean 20 milliseconds at 300 mg).

In conclusion, AZD3839 reduced plasma Aβ40 and Aβ42, demonstrating clinical peripheral proof of mechanism. Pre‐clinical models were predictive for the effect of AZD3839 on the human plasma biomarker in a strictly quantitative manner.
iPortal: the swiss grid proteomics portal: Requirements and new features based on experience and usability considerations
Authors: Kunszt Peter , Blum Lorenz , Hullár Béla , Schmid Emanuel , Srebniak Adam , Wolski Witold , Rinn Bernd , Elmer Franz‐Josef , Ramakrishnan Chandrasekhar , Quandt Andreas , Malmström Lars
Published: May 2014

Development of workflow and data management systems are challenging because of the need to provide a service for users with varying degrees of expertise from novices to experts with more knowledge than the developers. We have received feedback from users and developers on the functionality and usability of the Swiss Grid Proteomics Portal, now called iPortal, during its first year of operation. Monitoring and interaction with the production system under heavy use have provided further information on how to improve efficiency and stability. In a second, highly upgraded version of iPortal, we have introduced several new concepts based on this feedback. In this paper, we detail the requirements and the improvements we have made, and also give an outlook on future directions. Copyright © 2014 John Wiley & Sons, Ltd.
Artificial bee colony based energy‐aware resource utilization technique for cloud computing
Authors: Kansal Nidhi Jain , Chana Inderveer
Published: May 2014

Cloud computing is a form of distributed computing, which promises to deliver reliable services through next‐generation data centers that are built on virtualized compute and storage technologies. It is becoming truly ubiquitous and with cloud infrastructures becoming essential components for providing Internet services, there is an increase in energy‐hungry data centers deployed by cloud providers. As cloud providers often rely on large data centers to offer the resources required by the users, the energy consumed by cloud infrastructures has become a key environmental and economical concern. Much energy is wasted in these data centers because of under‐utilized resources hence contributing to global warming. To conserve energy, these under‐utilized resources need to be efficiently utilized and to achieve this, jobs need to be allocated to the cloud resources in such a way so that the resources are used efficiently and there is a gain in performance and energy efficiency. In this paper, a model for energy‐aware resource utilization technique has been proposed to efficiently manage cloud resources and enhance their utilization. It further helps in reducing the energy consumption of clouds by using server consolidation through virtualization without degrading the performance of users’ applications. An artificial bee colony based energy‐aware resource utilization technique corresponding to the model has been designed to allocate jobs to the resources in a cloud environment. The performance of the proposed algorithm has been evaluated with the existing algorithms through the CloudSim toolkit. The experimental results demonstrate that the proposed technique outperforms the existing techniques by minimizing energy consumption and execution time of applications submitted to the cloud. Copyright © 2014 John Wiley & Sons, Ltd.
An architecture‐level graphics processing unit energy model
Authors: Wang Zhuowei , Cheng Lianglun , Zhao Wuqing , Xiong Naixue
Published: May 2014

With the continued development of hardware and software, graphics processing unit (GPU) has been used in general purpose computational fields, while accelerating applications for CPUs. To achieve high computing performance, a GPU typically includes hundreds of computing units. The high density of computing resource on‐chip incurs high power consumption as well as engendering high performance. The power consumption problem has become one of the most important problems for the development of GPUs. Focusing on a CPU‐GPU heterogeneous parallel system, this research proposed an architecture‐level GPU energy model, with the aim of reducing system energy demand and improving system efficiency. Taking the influences of memory and temperature on GPU energy demand into account, a dynamic energy model based on division of computation and memory and a static energy model based on real‐time temperature perception were established. Validation, through the evaluation and comparative analysis of nine typical GPU programmes, demonstrated that these models could reduce chip energy demand under the performance constraint conditions imposed. Copyright © 2014 John Wiley & Sons, Ltd.
Robust reliable sampled‐data H∞ control for uncertain stochastic systems with random delay
Authors: Sakthivel Rathinasamy , Selvi Subramaniam , Mathiyalagan Kalidass , Arunkumar Arumugham
Published: May 2014

In this article, the problem of robust reliable sampled‐data
control for a class of uncertain nonlinear stochastic system with random delay control input against actuator failures has been studied. In the considered system, the parameter uncertainty satisfies the norm bounded condition and the involved time delay in control input are assumed to be randomly time‐varying which is modeled by introducing Bernoulli distributed sequences. By constructing a novel Lyapunov–Krasovskii functional involving with the lower and upper bounds of the delay, a new set of sufficient conditions are derived in terms of linear matrix inequalities (LMIs) for ensuring the robust asymptotic stability of the uncertain nonlinear stochastic system with random delay and disturbance attenuation level
about its equilibrium point for all possible actuator failures. In particular, Schur complement together with Jenson's integral inequality is utilized to substantially simplify the derivation in the main results. The derived analytic results are applied to design robust reliable sampled‐data
controller for hanging crane structure model and simulation results are provided to demonstrate the effectiveness of the proposed control law. © 2014 Wiley Periodicals, Inc. Complexity 21: 42–58, 2015
Survival and growth patterns of white spruce (Picea glauca [Moench] Voss) rangewide provenances and their implications for climate change adaptation
Authors: Lu Pengxin , Parker William H. , Cherry Marilyn , Colombo Steve , Parker William C. , Man Rongzhou , Roubal Ngaire
Published: May 2014

Intraspecific assisted migration (ISAM) through seed transfer during artificial forest regeneration has been suggested as an adaptation strategy to enhance forest resilience and productivity under future climate. In this study, we assessed the risks and benefits of ISAM in white spruce based on long‐term and multilocation, rangewide provenance test data. Our results indicate that the adaptive capacity and growth potential of white spruce varied considerably among 245 range‐wide provenances sampled across North America; however, the results revealed that local populations could be outperformed by nonlocal ones. Provenances originating from south‐central Ontario and southwestern Québec, Canada, close to the southern edge of the species' natural distribution, demonstrated superior growth in more northerly environments compared with local populations and performed much better than populations from western Canada and Alaska, United States. During the 19–28 years between planting and measurement, the southern provenances have not been more susceptible to freezing damage compared with local populations, indicating they have the potential to be used now for the reforestation of more northerly planting sites; based on changing temperature, these seed sources potentially could maintain or increase white spruce productivity at or above historical levels at northern sites. A universal response function (URF), which uses climatic variables to predict provenance performance across field trials, indicated a relatively weak relationship between provenance performance and the climate at provenance origin. Consequently, the URF from this study did not provide information useful to ISAM. The ecological and economic importance of conserving white spruce genetic resources in south‐central Ontario and southwestern Québec for use in ISAM is discussed.
Development of a Nonlinear Soft Sensor Using a GMDH Network for a Refinery Crude Distillation Tower
Authors: Fujii Kenzo , Yamamoto Toru
Published: May 2014

In atmospheric distillation processes, stabilization of processes is required in order to optimize the crude‐oil composition that corresponds to product market conditions. However, the process control systems sometimes fall into unstable states in the case where unexpected disturbances are introduced, and these unusual phenomena have had an undesirable effect on certain products. Furthermore, a useful chemical engineering model has not yet been established for these phenomena. This remains a serious problem in atmospheric distillation processes. This paper describes a new modeling scheme to predict unusual phenomena in the atmospheric distillation process using a GMDH (Group Method of Data Handling) network, which is a type of network model. According to the GMDH network, the model structure can be determined systematically. However, the method of least squares has been commonly utilized in determining weight coefficients (model parameters). Estimation accuracy is not entirely essential, because the sum of the squared errors between the measured values and estimates is evaluated. Therefore, instead of evaluating the sum of the squared errors, the sum of the absolute values of the errors is introduced and the Levenberg–Marquardt method is employed in order to determine the model parameters. The effectiveness of the proposed method is evaluated by foaming prediction in the crude oil switching operation in the atmospheric distillation process.
Modeling of Nonlinear Magnetizing Characteristics of Pole Transformer for Analyzing Islanding Prevention of Photovoltaic System
Authors: Yoshida Yoshiaki , Suzuki Hirokazu , Fujiwara Koji , Ishihara Yoshiyuki
Published: May 2014

With increasing penetration of distributed generators such as photovoltaic (PV) systems in distribution systems, it is very important to quickly detect islanding caused by power system faults in order to assure electrical safety. We have developed a nonlinear magnetizing characteristics model of pole transformers for use in analyzing islanding prevention in PV systems. Basic experiments on the islanding detection were performed for verification of the proposed model. Analytical results obtained by the proposed model agreed well with experimental results.
Sphingosine‐1‐phosphate lyase is expressed by CD68+ cells on the parenchymal side of marginal reticular cells in human lymph nodes
Authors: Park Saem Mul , Angel Catherine E. , McIntosh Julie D. , Brooks Anna E. S. , Middleditch Martin , Chen Chun‐Jen J. , Ruggiero Katya , Cebon Jonathan , Rod Dunbar P.
Published: May 2014

Lymph nodes (LNs) form the intersection between the vascular and lymphatic systems. Lymphocytes and antigen‐presenting cells (APCs) traffic between these systems, but the barriers crossed during this trafficking in human LNs are poorly defined. We identified a population of cells in human LNs that lines the boundary between the parenchyma and lymphatic sinuses, consistent with descriptions of marginal reticular cells (MRCs) in murine LNs. Human MRCs are CD141high podoplanin+, CD90+, ICAM1+, and VCAM1+ but lack endothelial and hematopoietic cell markers, or alpha‐smooth muscle actin. We then examined expression of the enzyme sphingosine‐1‐phosphate (S1P) lyase (SGPL1) relative to the boundary defined by MRCs. SGPL1 expression was almost exclusively restricted to cells on the parenchymal side of MRCs, consistent with a role in maintaining the S1P gradient between the sinuses and the parenchyma. Surprisingly the cells expressing SGPL1 in the parenchyma were CD68+ APCs. CD68+ APCs generated from human monocytes were able to internalize and irreversibly degrade S1P, and this activity was inhibited by the S1P analogue FTY720. This work provides a map of the key structures at the boundary where human lymphocytes egress into sinuses, and identifies a novel potential mechanism for the activity of S1P analogues in humans.
Resolving Salmonella infection reveals dynamic and persisting changes in murine bone marrow progenitor cell phenotype and function
Authors: Ross Ewan A. , Flores‐Langarica Adriana , Bobat Saeeda , Coughlan Ruth E. , Marshall Jennifer L. , Hitchcock Jessica R. , Cook Charlotte N. , Carvalho‐Gaspar Manuela M. , Mitchell Andrea M. , Clarke Mary , Garcia Paloma , Cobbold Mark , Mitchell Tim J. , Henderson Ian R. , Jones Nick D. , Anderson Graham , Buckley Christopher D. , Cunningham Adam F.
Published: May 2014

The generation of immune cells from BM precursors is a carefully regulated process. This is essential to limit the potential for oncogenesis and autoimmunity yet protect against infection. How infection modulates this is unclear. Salmonella can colonize systemic sites including the BM and spleen. This resolving infection has multiple IFN‐γ‐mediated acute and chronic effects on BM progenitors, and during the first week of infection IFN‐γ is produced by myeloid, NK, NKT, CD4+ T cells, and some lineage‐negative cells. After infection, the phenotype of BM progenitors rapidly but reversibly alters, with a peak ∼30‐fold increase in Sca‐1hi progenitors and a corresponding loss of Sca‐1lo/int subsets. Most strikingly, the capacity of donor Sca‐1hi cells to reconstitute an irradiated host is reduced; the longer donor mice are exposed to infection, and Sca‐1hic‐kitint cells have an increased potential to generate B1a‐like cells. Thus, Salmonella can have a prolonged influence on BM progenitor functionality not directly related to bacterial persistence. These results reflect changes observed in leucopoiesis during aging and suggest that BM functionality can be modulated by life‐long, periodic exposure to infection. Better understanding of this process could offer novel therapeutic opportunities to modulate BM functionality and promote healthy aging.
Impact of a stepwise protocol for treating pain on pain intensity in nursing home patients with dementia: A cluster randomized trial
Authors: Sandvik R.K. , Selbaek G. , Seifert R. , Aarsland D. , Ballard C. , Corbett A. , Husebo B.S.
Published: May 2014

Background

Pain is frequent and distressing in people with dementia, but no randomized controlled trials have evaluated the effect of analgesic treatment on pain intensity as a key outcome.

Methods

Three hundred fifty‐two people with dementia and significant agitation from 60 nursing home units were included in this study. These units, representing 18 nursing homes in western Norway, were randomized to a stepwise protocol of treating pain (SPTP) or usual care. The SPTP group received acetaminophen, morphine, buprenorphine transdermal patch and pregabalin for 8 weeks, with a 4‐week washout period. Medications were governed by the SPTP and each participant's existing prescriptions. We obtained pain intensity scores from 327 patients (intervention n = 164, control n = 163) at five time points assessed by the primary outcome measure, Mobilization‐Observation‐Behaviour‐Intensity‐Dementia‐2 (MOBID‐2) Pain Scale. The secondary outcome was activities of daily living (ADL). We used a linear intercept mixed model in a two‐way repeated measures configuration to assess change over time and between groups.

Results

The SPTP conferred significant benefit in MOBID‐2 scores compared with the control group [average treatment effect (ATE) −1.388; p < 0.001] at week 8, and MOBID‐2 scores worsened during the washout period (ATE = −0.701; p = 0.022). Examining different analgesic treatments, benefit was conferred to patients receiving acetaminophen compared with the controls at week 2 (ATE = −0.663; p = 0.010), continuing to increase until week 8 (ATE = −1.297; p < 0.001). Although there were no overall improvements in ADL, an increase was seen in the group receiving acetaminophen (ATE = +1.0; p = 0.022).

Conclusion

Pain medication significantly improved pain in the intervention group, with indications that acetaminophen also improved ADL function.
Getting started with open‐hardware: Development and control of microfluidic devices
Authors: da Costa Eric Tavares , Mora Maria F. , Willis Peter A. , do Lago Claudimir L. , Jiao Hong , Garcia Carlos D.
Published: May 2014

Understanding basic concepts of electronics and computer programming allows researchers to get the most out of the equipment found in their laboratories. Although a number of platforms have been specifically designed for the general public and are supported by a vast array of on‐line tutorials, this subject is not normally included in university chemistry curricula. Aiming to provide the basic concepts of hardware and software, this article is focused on the design and use of a simple module to control a series of PDMS‐based valves. The module is based on a low‐cost microprocessor (Teensy) and open‐source software (Arduino). The microvalves were fabricated using thin sheets of PDMS and patterned using CO2 laser engraving, providing a simple and efficient way to fabricate devices without the traditional photolithographic process or facilities. Synchronization of valve control enabled the development of two simple devices to perform injection (1.6 ± 0.4 μL/stroke) and mixing of different solutions. Furthermore, a practical demonstration of the utility of this system for microscale chemical sample handling and analysis was achieved performing an on‐chip acid–base titration, followed by conductivity detection with an open‐source low‐cost detection system. Overall, the system provided a very reproducible (98%) platform to perform fluid delivery at the microfluidic scale.
Volatility Risk Premium in Indian Options Prices
Authors: Garg Sonia , Vipul
Published: May 2014

The article examines the volatility forecasting and option pricing performance of model‐free implied volatility (MFIV) in comparison to that of the forecasts based on model‐free realized volatility (RV). There is evidence that the forecasts based on RV are significantly more efficient and less biased than those based on MFIV, whereas the option prices based on MFIV are significantly more efficient and less biased than those based on RV. These contrasting results can be reconciled by accounting for the volatility risk premium (VRP), which is found to follow an autoregressive process in this study. The significant daily returns, observed for various option strategies used to exploit the VRP, are substantially reduced, when the normal transaction costs are accounted for. Although the VRP is priced in the Indian options market, it can provide economic benefits only to those option writers, who have sufficiently low transaction costs. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 35:795–812, 2015
Valuing Retail Credit Tranches with Structural, Double Mixture Models
Authors: Bae Taehan , Iscoe Ian , Kim Changki
Published: May 2014

This study considers the class of double mixtures to model a general dependence structure beyond the typical conditional independence assumption among the entities in a homogeneous credit portfolio. The two mixing components are (i) the marginal distributions of the systemic and idiosyncratic factors and (ii) the conditional probability measure that incorporates the further dependence structure among the idiosyncratic factors, given the systemic factor. For a large portfolio, the fair spread of a structured retail credit tranche is expressed in terms of the sums of single integrals, which can be easily computed numerically. We discuss the behaviors of tranche spreads under several double mixture models, and calibrate these models to market data. © 2015 Wiley Periodicals, Inc. Jrl Fut Mark 35:849–867, 2015
Hypoactivation in right inferior frontal cortex is specifically associated with motor response inhibition in adult ADHD
Authors: Morein‐Zamir Sharon , Dodds Chris , van Hartevelt Tim J. , Schwarzkopf Wolfgang , Sahakian Barbara , Müller Ulrich , Robbins Trevor
Published: May 2014

Adult ADHD has been linked to impaired motor response inhibition and reduced associated activation in the right inferior frontal cortex (IFC). However, it is unclear whether abnormal inferior frontal activation in adult ADHD is specifically related to a response inhibition deficit or reflects a more general deficit in attentional processing. Using functional magnetic resonance imaging, we tested a group of 19 ADHD patients with no comorbidities and a group of 19 healthy control volunteers on a modified go/no‐go task that has been shown previously to distinguish between cortical responses related to response inhibition and attentional shifting. Relative to the healthy controls, ADHD patients showed increased commission errors and reduced activation in inferior frontal cortex during response inhibition. Crucially, this reduced activation was observed when controlling for attentional processing, suggesting that hypoactivation in right IFC in ADHD is specifically related to impaired response inhibition. The results are consistent with the notion of a selective neurocognitive deficit in response inhibition in adult ADHD associated with abnormal functional activation in the prefrontal cortex, whilst ruling out likely group differences in attentional orienting, arousal and motivation. Hum Brain Mapp 35:5141–5152, 2014. © 2014 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc.
Current epidemiology of hepatitis E virus infection in the United States: Low seroprevalence in the National Health and Nutrition Evaluation Survey
Authors: Ditah Ivo , Ditah Fausta , Devaki Pardha , Ditah Calistus , Kamath Patrick S. , Charlton Michael
Published: May 2014

Analysis of the National Health and Nutrition Evaluation Survey (NHANES) 1988-1994 dataset found a relatively high seroprevalence (21%) of hepatitis E virus (HEV) infection in the U.S. general population. Using data obtained within the NHANES 2009-2010 survey, where a high performance assay for HEV was used, we estimated the weighted seroprevalence of HEV infection among U.S. individuals 6 years and older. We also evaluated factors associated with HEV seropositivity. A total of 8,814 individuals were included in the analysis. The median age of study participants was 37 years (interquartile range [IQR] 17-58 years), with 51.2% being female. The weighted national seroprevalence of HEV was 6% (95% confidence interval [CI] 5.1%-6.9%). About 0.5% of those with HEV had evidence of recent exposure (immunoglobulin M-positive). In the univariate analyses, factors associated with HEV seropositivity were increasing age (P-trend < 0.001), birth outside of the U.S., Hispanic race, and “meat” consumption (>10 times/month). No significant association was observed with low socioeconomic status, water source, or level of education. In the multivariate analysis, only older age remained predictive of HEV seropositivity. Conclusion: The weighted national seroprevalence of HEV in the U.S. is much less than previously reported. Using data obtained with a high performance assay, the seroprevalence of HEV was estimated at 6.0% in the U.S. Based on these results, the seroprevalence of HEV is only one-third as high as previously reported. (Hepatology 2014;60:815–822)
Addressing the Stress of Work and Elder Caregiving of the Graying Workforce: The Moderating Effects of Financial Strain on the Relationship Between Work‐Caregiving Conflict and Psychological Well‐Being
Authors: Kim Najung , Gordon Judith R.
Published: May 2014

Human resource policies and practices must consider the issues associated with an aging workforce, and, more specifically, the stress experienced by those involved in caring for elders. This study examined such stress by studying the relationship between work–elder caregiving conflict and well‐being, as well as the role of perceived financial need in moderating that relationship. The sample included 583 women who worked full‐time and had significant elder caregiving responsibilities. The analysis showed that work interfering with caregiving (WIC) was significantly associated with both positive and negative affect, but caregiving interfering with work (CIW) was not significantly associated with either. Perceived financial need decreased older women's psychological well‐being and moderated the relationship between work–elder caregiving conflict and psychological well‐being such that the negative effect of WIC was stronger for older women with higher perceived financial need, while CIW decreased the well‐being of older women with lower perceived financial need but not for those with higher need. The results stress the importance of considering elder care as a source of work‐family conflict when managing the aging workforce as well as suggest a way to attenuate the negative effect of work‐family conflict by managing the perception of financial resources and needs of the employees. © 2014 Wiley Periodicals, Inc.