bluuebunny/crossref_metadata_2025 huggingface dataset:
Decellularization of intact tissue enables MALDI imaging mass spectrometry analysis of the extracellular matrix
Authors: Gessel Megan , Spraggins Jeffrey M. , Voziyan Paul , Hudson Billy G , Caprioli Richard M
Published: October 2015

Matrix‐assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) is a powerful molecular mapping technology that offers unbiased visualization of the spatial arrangement of biomolecules in tissue. Although there has been a significant increase in the number of applications employing this technology, the extracellular matrix (ECM) has received little attention, likely because ECM proteins are mostly large, insoluble and heavily cross‐linked. We have developed a new sample preparation approach to enable MALDI IMS analysis of ECM proteins in tissue. Prior to freezing and sectioning, intact tissues are decellularized by incubation in sodium dodecyl sulfate. Decellularization removes the highly abundant, soluble species that dominate a MALDI IMS spectrum while preserving the structural integrity of the ECM. In situ tryptic hydrolysis and imaging of tryptic peptides are then carried out to accommodate the large sizes of ECM proteins. This new approach allows the use of MALDI IMS for identification of spatially specific changes in ECM protein expression and modification in tissue. Copyright © 2015 John Wiley & Sons, Ltd.
Mass spectrometric profiling of valepotriates possessing various acyloxy groups from Valeriana jatamansi
Authors: Lin Sheng , Ye Ji , Liang Xu , Zhang Xi , Su Juan , Fu Peng , Lv Di‐Ya , Shan Lei , Shen Yun‐Heng , Li Hui‐Liang , Yang Xian‐Wen , Zhang Wei‐Dong
Published: October 2015

Valepotriates, plant secondary metabolites of the family Valerianaceae, contain various acyloxy group linkages to the valepotriate nucleus and exhibit significant biological activities. Identification of valepotriates is important to uncover potential lead compounds for the development of new sedative and antitumor drugs. However, making their structure elucidation by nuclear magnetic resonance (NMR) experiments is too difficult to be realized because of the overlapped carbonyl carbon signals of acyloxy groups substituted at different positions. Thus, the mass spectrometric profiling of these compounds in positive ion mode was developed to unveil the exact linkage of acyloxy group and the core of valepotriate. In this study, electrospray ionization tandem multistage mass spectrometry (ESI‐MS/MSn) in ion trap and collision‐induced dissociation tandem MS were used to investigate the fragmentation pathways of four types of valepotriates in Valeriana jatamansi, including 5‐hydroxy‐5,6‐dihydrovaltrate hydrin (5‐hydroxy‐5,6‐dihydrovaltrate chlorohydrin), 5,6‐dihydrovaltrate hydrin (5,6‐dihydrovaltrate chlorohydrin), 5‐hydroxy‐5,6‐dihydrovaltrate and valtrate hydrin (valtrate chlorohydrin). The high‐resolution mass spectrum (HRMS) data of all the investigated valepotriates from quadrupole time‐of‐flight MS/MS were used as a supportive of the fragmentation rules we hypothesized from ion‐trap stepwise MSn. As a result, the loss sequence of acyloxy groups and the abundance of key product ions, in combination with the characteristic product ions corresponding to the valepotriate nucleus, could readily differentiate the four different types of valepotriates. The summarized fragmentation rules were also successfully exploited for the structural characterization of three new trace valepotriates from V. jatamansi. The results indicated that the developed analytical method could be employed as a rapid, effective technique for structural characterization of valepotriates, especially for the trace compounds that could not be identified by NMR techniques. This study may also arouse interest for further structural analysis of other valepotriate‐containing type herbal medicines. Copyright © 2015 John Wiley & Sons, Ltd.
Evaluation of mass spectrometric data using principal component analysis for determination of the effects of organic lakes on protein binder identification
Authors: Hrdlickova Kuckova Stepanka , Rambouskova Gabriela , Hynek Radovan , Cejnar Pavel , Oltrogge Doris , Fuchs Robert
Published: October 2015

Matrix‐assisted laser desorption/ionisation–time of flight (MALDI‐TOF) mass spectrometry is commonly used for the identification of proteinaceous binders and their mixtures in artworks. The determination of protein binders is based on a comparison between the m/z values of tryptic peptides in the unknown sample and a reference one (egg, casein, animal glues etc.), but this method has greater potential to study changes due to ageing and the influence of organic/inorganic components on protein identification. However, it is necessary to then carry out statistical evaluation on the obtained data. Before now, it has been complicated to routinely convert the mass spectrometric data into a statistical programme, to extract and match the appropriate peaks. Only several ‘homemade’ computer programmes without user‐friendly interfaces are available for these purposes.

In this paper, we would like to present our completely new, publically available, non‐commercial software, ms‐alone and multiMS‐toolbox, for principal component analyses of MALDI‐TOF MS data for R software, and their application to the study of the influence of heterogeneous matrices (organic lakes) for protein identification. Using this new software, we determined the main factors that influence the protein analyses of artificially aged model mixtures of organic lakes and fish glue, prepared according to historical recipes that were used for book illumination, using MALDI‐TOF peptide mass mapping. Copyright © 2015 John Wiley & Sons, Ltd.
Health benefit of fucosterol from marine algae: a review
Authors: Abdul Qudeer Ahmed , Choi Ran Joo , Jung Hyun Ah , Choi Jae Sue
Published: October 2015

Seaweeds belong to a group of marine plants known as algae, which are consumed as sea vegetables in several Asian countries. Recent studies have focused on the biological and pharmacological activities of seaweeds and their highly bioactive secondary metabolites because of their potential in the development of new pharmaceutical agents. Although several varieties of bioactive novel compounds such as phlorotannins, diterpenes and polysaccharides from seaweeds have already been well scrutinized, fucosterol as a phytosterol still needs to reinvent itself. Fucosterol (24‐ethylidene cholesterol) is a sterol that can be isolated from algae, seaweed and diatoms. Fucosterol exhibits various biological therapeutics, including anticancer, antidiabetic, antioxidant, hepatoprotective, antihyperlipidemic, antifungal, antihistaminic, anticholinergic, antiadipogenic, antiphotodamaging, anti‐osteoporotic, blood cholesterol reducing, blood vessel thrombosis preventive and butyrylcholinesterase inhibitory activities. In this review, we address some potential approaches for arbitrating novel fucosterol biologics in the medical field, focusing on the selection of personalized drug candidates and highlighting the challenges and opportunities regarding medical breakthroughs. We also highlight recent advances made in the design of this novel compound, as the significant health benefits from using these optimized applications apply to the nutraceutical and pharmaceutical fields. © 2015 Society of Chemical Industry
Effects of an equol‐producing bacterium isolated from human faeces on isoflavone and lignan metabolism in mice
Authors: Tamura Motoi , Hori Sachiko , Nakagawa Hiroyuki , Yamauchi Satoshi , Sugahara Takuya
Published: October 2015

BACKGROUND

Equol is a metabolite of daidzein that is produced by intestinal microbiota. The oestrogenic activity of equol is stronger than daidzein. Equol‐producing bacteria are believed to play an important role in the gut. The rod‐shaped and Gram‐positive anaerobic equol‐producing intestinal bacterium Slackia TM‐30 was isolated from healthy human faeces and its effects on urinary phyto‐oestrogen, plasma and faecal lipids were assessed in adult mice.

RESULTS

The urinary amounts of equol in urine were significantly higher in mice receiving the equol‐producing bacterium TM‐30 (BAC) group than in the control (CO) group (P < 0.05). However, no significant differences were observed between the urinary amounts of daidzein, dihydrodaidzein, enterodiol, and enterolactone between the BAC and CO groups. No significant differences in the plasma lipids were observed between the two groups. The lipid content (% dry weight) in the faeces sampled on the final day of the experiment tended to be higher in the BAC group than in the CO group (P = 0.07).

CONCLUSION

Administration of equol‐producing bacterium TM‐30 affected the urinary amounts of phyto‐oestrogens and the faecal lipid contents of mice. The equol‐producing bacterium TM‐30 likely influences the metabolism of phyto‐oestrogen via changes in the gastrointestinal environment. © 2015 Society of Chemical Industry
Selected chemical compounds in firm and mellow persimmon fruit before and after the drying process
Authors: Senica Mateja , Veberic Robert , Grabnar Jana Jurhar , Stampar Franci , Jakopic Jerneja
Published: October 2015

BACKGROUND

Persimmon is a seasonal fruit and only available in fresh form for a short period of each year. In addition to freezing, drying is the simplest substitute for the fresh fruit and accessible throughout the year. The effect of mellowing and drying was evaluated in ‘Tipo’ persimmon, an astringent cultivar.

RESULTS

‘Tipo’ firm fruit contained high levels of tannins (1.1 mg g−1 DW), which were naturally decreased to 0.2 mg g−1 DW after mellowing. The drying process greatly impacted the contents of carotenoids, total phenols, individual phenolics, tannins, organic acids, sugars and colour parameters in firm and mellow fruit. The reduction of tannins, phenolic compounds and organic acids were accompanied by the increase of sugars and carotenoids, improving the colour of the analysed samples.

CONCLUSION

These results showed that the drying process improved the quality of persimmon products and extended their shelf life. © 2015 Society of Chemical Industry
Land Cover Transition in Northern Tanzania
Authors: Ouedraogo Issa , Barron Jennie , Tumbo Siza D. , Kahimba Frederic C.
Published: October 2015

Land conversion in sub‐Saharan Africa has profound biophysical, ecological, political and social consequences for human well‐being and ecosystem services. Understanding the process of land cover changes and transitions is essential for good ecosystem management policy that would lead to improved agricultural production, human well‐being and ecosystems health. This study aimed to assess land cover transitions in a typical semi‐arid degraded agro‐ecosystems environment within the Pangani river basin in northern Tanzania. Three Landsat images spanning over 30 years were used to detect random and systematic patterns of land cover transition in a landscape dominated by crop and livestock farming. Results revealed that current land cover transition is driven by a systematic process of change dominated by the following: (i) transition from degraded land to sparse bushland (10·8%); (ii) conversion from sparse bushland to dense bushland in lowland areas (6·0%); (iii) conversion from bushland to forest (4·8%); and (iv) conversion from dense bushland to cropland in the highlands (4·5%). Agricultural lands under water harvesting technology adoption show a high degree of persistence (60–80%) between time slices. This suggests that there is a trend in land‐use change towards vegetation improvement in the catchment with a continuous increase in the adoption of water harvesting technologies for crop and livestock farming. This can be interpreted as a sign of agricultural intensification and vegetation regrowth in the catchment. Copyright © 2015 John Wiley & Sons, Ltd.
Glabridin, an isoflavan from licorice root, upregulates paraoxonase 2 expression under hyperglycemia and protects it from oxidation
Authors: Yehuda Itamar , Madar Zecharia , Leikin‐Frenkel Alicia , Szuchman‐Sapir Andrea , Magzal Faiga , Markman Gilad , Tamir Snait
Published: October 2015

Scope

Hyperglycemia is associated with oxidative stress, which accelerates cardiovascular complications. This study investigates the potential of glabridin to regulate paraoxonase 2 (PON2) levels, in vivo, and explores the glabridin protective effect on PON2 through tryptophan‐fluorescence quenching and mass spectrometry.

Methods and results

Adult mouse offspring of saturated fatty acids fed mothers, which developed hyperglycemia after exposure to a high fat diet in their adult life, had lower levels of heart PON2 mRNA and protein expression than did the control mice (64 and 26%, respectively). Glabridin supplementation significantly upregulated PON2 mRNA and protein expression in the liver (2.1‐fold and 2.6‐fold, respectively) and heart (2.5‐fold and 1.6‐fold, respectively) in these mice. In vitro studies demonstrated that the fluorescence quenching of PON2 by glabridin was a result of the formation of a glabridin–PON2 interaction. The binding constant (7.61 × 105 M−1) and the ΔG (–33.55kJ/mol) indicated that this interaction was driven by a hydrophobic force, which confers protection against CuSO4‐induced PON2 oxidation.

Conclusion

Such results indicate that glabridin preserves the anti‐atherogenic abilities of PON2 by maintaining its levels, in vivo. The glabridin–PON2 interaction may be the mechanism by which glabridin protects PON2 from oxidation, thus contributing to the protection of PON2 activity in hyperglycemia.
The Learning Process and Technological Change in Wind Power: Evidence from China's CDM Wind Projects
Authors: Tang Tian , Popp David
Published: October 2015

The Clean Development Mechanism (CDM) is a project‐based carbon trade mechanism that subsidizes the users of climate‐friendly technologies and encourages technology transfer. The CDM has provided financial support for a large share of Chinese wind projects since 2002. Using pooled cross‐sectional data of 486 registered CDM wind projects in China from 2002 to 2009, we examine the determinants of technological change in wind power from a learning perspective. We use a spatial error model to estimate the effects of different channels of learning—learning through R&D in wind turbine manufacturing, learning from a firm's previous wind project experience, spillovers from industry‐wide project experience, and learning through the network interaction between project developer and turbine manufacturer—on technological change, measured as reductions in projected costs or as increased capacity factor across CDM wind projects. While we find that a project developer's previous experience matters, interactions between a wind project developer and its partner foreign turbine manufacturer lead to the largest cost reductions and capacity factor improvement. We also find that spillovers from industry‐wide experience only exist for wind farm installation. The evidence of industry‐wide spillovers and the joint learning within partnerships between project developers and foreign turbine manufacturers supports the subsidies to users of wind technologies, and policy regimes that promote international collaboration and technology transfer.
Model systems of human papillomavirus‐associated disease
Authors: Doorbar John
Published: October 2015

Human papillomaviruses (HPVs) cause a range of serious diseases, including the vast majority of cervical cancers, most anal cancers and around half of head and neck cancers. They are also responsible for troublesome benign epithelial lesions, including genital warts and laryngeal papillomas, and in some individuals HPVs lead to recurrent respiratory papillomatosis and other difficult‐to‐manage diseases. As a result, there is a great need for model systems that accurately mimic papillomavirus infections in humans. This is complicated by the diverse variety of HPVs, which now number over 200 types, and the different strategies they have evolved to persist in the population. The most well‐developed models involve the culture of HPV‐containing keratinocytes in organotypic raft culture, an approach which appears to accurately mimic the life cycle of several of the high‐risk cancer‐associated HPV types. Included amongst these are HPV16 and 18, which cause the majority of cervical cancers. The low‐risk HPV types persist less well in tissue‐culture models, and our ability to study the productive life cycle of these viruses is more limited. Although ongoing research is likely to improve this situation, animal models of papillomavirus disease can provide considerable basic information as to how lesions form, regress and can be controlled by the immune system. The best studied are cottontail rabbit papillomavirus, rabbit oral papillomavirus and, more recently, mouse papillomavirus (MmuPV), the last of which is providing exciting new insights into viral tropisms and immune control. In addition, transgenic models of disease have helped us to understand the consequences of persistent viral gene expression and the importance of co‐factors such as hormones and UV irradiation in the development of neoplasia and cancer. It is hoped that such disease models will eventually lead us to better understanding and better treatments for human disease. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Models of endometriosis and their utility in studying progression to ovarian clear cell carcinoma
Authors: King Claire M , Barbara Cynthia , Prentice Andrew , Brenton James D , Charnock‐Jones D Stephen
Published: October 2015

Endometriosis is a common benign gynaecological condition affecting at least 10% of women of childbearing age and is characterized by pain – frequently debilitating. Although the exact prevalence is unknown, the economic burden is substantial (∼$50 billion a year in the USA alone) and it is associated with considerable morbidity. The development of endometriosis is inextricably linked to the process of menstruation and thus the models that best recapitulate the human disease are in menstruating non‐human primates. However, the use of these animals is ethically challenging and very expensive. A variety of models in laboratory animals have been developed and the most recent are based on generating menstrual‐like endometrial tissue that can be transferred to a recipient animal. These models are genetically manipulable and facilitate precise mechanistic studies. In addition, these models can be used to study malignant transformation in epithelial ovarian carcinoma. Epidemiological and molecular evidence indicates that endometriosis is the most plausible precursor of both clear cell and endometrioid ovarian cancer (OCCA and OEA, respectively). While this progression is rare, understanding the underlying mechanisms of transformation may offer new strategies for prevention and therapy. Our ability to pursue this is highly dependent on improved animal models but the current transgenic models, which genetically modify the ovarian surface epithelium and oviduct, are poor models of ectopic endometrial tissue. In this review we describe the various models of endometriosis and discuss how they may be applicable to developing our mechanistic understanding of OCCA and OEA. © 2015 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
Investigation of thermal properties and mechanical properties of reduced graphene oxide/polyimide resin composites
Authors: Liu Peijiang , Yao Zhengjun , Zhou Jintang
Published: October 2015

In this article, reduced graphene oxide/polyimide resin composites which exhibited enhancements in mechanical properties were successfully fabricated by hot‐pressing, and reduced graphene oxide nanosheets were synthesized by thermal reduced method, which can readily mix with PI powders in aqueous solution by sonication process. The chemical structures of rGO were carefully characterized by X‐ray diffraction, Fourier transfer infrared spectroscopy and X‐ray photoelectron spectroscopy. The field emission scanning electron microscopy observations showed that the rGO displayed excellent dispersibility and compatibility with the PI matrix. The mechanical analysis indicated that the tensile and flexural strength values of the rGO/PI resin composite with 1.5 wt% rGO loading reached 80.7 and 133.3 MPa, respectively. Compared with pure PI, the optimized rGO/PI resin composite exhibited an enhancement of 30% in tensile strength, 19% in flexural strength and 27% in impact strength, due to the fine dispersion of high specific surface area of graphene nanosheets and the good adhesion between the rGO and the matrix. In addition, thermogravimetric analysis, dynamic mechanical analysis, and dielectric properties were also investigated. POLYM. COMPOS., 38:2321–2331, 2017. © 2015 Society of Plastics Engineers
Grafting polystyrene with various graft densities through epoxy groups of graphene nanolayers via atom transfer radical polymerization
Authors: Roghani‐Mamaqani Hossein
Published: October 2015

A double bond and amine group containing chemical (OD) was synthesized by coupling reaction of ethylenediamine and 3‐(chlorodimethylsilyl)propyl methacrylate. Subsequently, graphene oxide (GO) was functionalized with OD in different densities via ring opening of its epoxy groups. The graphene containing double bond (GOD) was incorporated into polystyrene (PS) chains by a grafting through atom transfer radical polymerization. Grafting of OD at the surface of GO was confirmed by Fourier transform infrared spectroscopy and thermogravimetric analysis (TGA). The interlayer spacing of the graphenes was evaluated by X‐ray diffraction. Molecular weight and PDI values of the free and attached PS chains were studied by size exclusion chromatography. TGA was also used to study the degradation points, char values, and grafting ratios. Relaxation of PS chains in the presence of graphene layers was evaluated by differential scanning calorimetry. Scanning electron and transmission electron microscopies show that flat graphene layers are wrinkled during oxidation and functionalization processes. POLYM. COMPOS., 38:2450–2458, 2017. © 2015 Society of Plastics Engineers
Benefit–Risk Assessment, Communication, and Evaluation (BRACE) throughout the life cycle of therapeutic products: overall perspective and role of the pharmacoepidemiologist
Authors: Radawski Christine , Morrato Elaine , Hornbuckle Kenneth , Bahri Priya , Smith Meredith , Juhaeri Juhaeri , Mol Peter , Levitan Bennett , Huang Han‐Yao , Coplan Paul , Li Hu ,   on behalf of the BRACE Special Interest Group
Published: October 2015

Purpose

Optimizing a therapeutic product's benefit–risk profile is an on‐going process throughout the product's life cycle. Different, yet related, benefit–risk assessment strategies and frameworks are being developed by various regulatory agencies, industry groups, and stakeholders. This paper summarizes current best practices and discusses the role of the pharmacoepidemiologist in these activities, taking a life‐cycle approach to integrated Benefit–Risk Assessment, Communication, and Evaluation (BRACE).

Methods

A review of the medical and regulatory literature was performed for the following steps involved in therapeutic benefit–risk optimization: benefit–risk evidence generation; data integration and analysis; decision making; regulatory and policy decision making; benefit–risk communication and risk minimization; and evaluation. Feedback from International Society for Pharmacoepidemiology members was solicited on the role of the pharmacoepidemiologist. The case example of natalizumab is provided to illustrate the cyclic nature of the benefit–risk optimization process.

Results

No single, globally adopted benefit–risk assessment process exists. The BRACE heuristic offers a way to clarify research needs and to promote best practices in a cyclic and integrated manner and highlight the critical importance of cross‐disciplinary input. Its approach focuses on the integration of BRACE activities for risk minimization and optimization of the benefit–risk profile.

Conclusion

The activities defined in the BRACE heuristic contribute to the optimization of the benefit–risk profile of therapeutic products in the clinical world at both the patient and population health level. With interdisciplinary collaboration, pharmacoepidemiologists are well suited for bringing in methodology expertise, relevant research, and public health perspectives into the BRACE process. Copyright © 2015 John Wiley & Sons, Ltd.
The adherence‐outcome relationship is not altered by diary‐driven adjustments of microelectronic monitor data
Authors: Eby Jessica , Chapman Jennifer , Marukutira Tafireyi , Anabwani Gabriel , Tshume Ontibile , Lepodisi Omphile , Dipotso Tebo , Mokete Keboletse , Gross Robert , Lowenthal Elizabeth
Published: October 2015

Purpose

The purpose of this study was to determine whether diary‐driven adjustment of Medication Event Monitoring System (MEMS) data based on Supporting Information strengthens the relationship between measured antiretroviral medication adherence and plasma HIV viral load (VL).

Methods

HIV+ adolescents on antiretroviral treatment were monitored with MEMS for 30 days preceding a VL measurement. The primary outcome was VL ≥ 400 copies/mL. Handwritten diaries were used to comprehensively record deviations from recommended use (bottle opened but dose not taken or bottle not opened and dose taken). Data were adjusted (“cleaned”) based on diary events. Data were “capped” at the prescribed number of doses/day. Receiver operator characteristic analysis compared the relationships between (i) raw MEMS data, (ii) diary‐cleaned, (iii) capped, or (iv) cleaned and capped MEMS data and VL.

Results

Over 30 days preceding VL measurements, 273 adolescents had 465 diary events. Capping resulted in fewer patients classified as 95% adherent (65.2%) compared with raw data (71.4%), p < 0.001. Adherence was highly associated with VL (OR 1.05, p < 0.001). The area under the receiver operating characteristic curve for continuous adherence compared with VL was 0.89 (95%CI: 0.82–0.95). Neither diary‐cleaning, capping, nor cleaning and capping MEMS data significantly altered the association between adherence and VL (p = 0.14, 0.40, and 0.19, respectively).

Conclusion

Medication Event Monitoring System data‐cleaning based on diary entries did not affect the adherence–VL relationship. Copyright © 2015 John Wiley & Sons, Ltd.
Sputtered Zn(O,S)/In2O3:H window layers for enhanced blue response of chalcopyrite solar cells
Authors: Steigert Alexander , Lauermann Iver , Niesen Thomas , Dalibor Thomas , Palm Jörg , Körner Stefan , Scherg‐Kurmes Harald , Muydinov Ruslan , Szyszka Bernd , Klenk Reiner
Published: October 2015

A combination of undoped ZnO and ZnO:Al is the most commonly used window layer stack for chalcopyrite solar cells. The high carrier density and thickness required to achieve a sufficiently low sheet resistance lead to optical absorption and cause losses in photocurrent, in particular in monolithically interconnected modules. Additionally, the band gap of the CdS buffer layer and of un‐doped ZnO limit the blue response. These losses could be avoided by using a transparent conductive oxide with high carrier mobility and wider band gap in combination with a buffer layer which also has a wide band gap. We propose a stack of Zn(O,S) and In2O3:H and report on our first results concerning its implementation. This stack is Cd‐free, highly transparent over a wide range, and can be deposited completely by sputtering which is an industrially proven dry process. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
Ab initio spin‐dependent band structures of carbon nanotubes
Authors: D'yachkov Pavel , Makaev Dmitry
Published: October 2015

Using a linearized augmented cylindrical wave (LACW) approach taking into account the screw and rotational symmetries of carbon nanotubes (CNTs), the first principles technique for the spin‐dependent band structure calculations of single‐walled CNTs is developed. The method is applicable to any tubule independent on diameter and chirality. The calculations are based on the two‐component relativistic Hamiltonian and muffin‐tin and exchange approximations for potentials. As example, the band structures of the three chiral, one armchair, and one zigzag CNTs are calculated and presented as the functions of the screw wave vector and rotational quantum number. The spin‐orbit coupling effects appear as splitting of some nonrelativistic electron bands equal to between the 0.01 and 1 meV depending on the CNTs structure, rotational quantum number, and Brillouin zone position. In agreement with previous empirical tight‐binding theories, almost perfect polarization of spin is observed in the case of chiral tubules. © 2015 Wiley Periodicals, Inc.
Evaluation of isolation in virtual machine environments encounter in effective attacks against memory
Authors: Hakamian Mir Alireza , Rahmani Amir Masoud
Published: October 2015

One of the main features of the hypervisor is the isolation among virtual machine (VM) environments. By isolation between VMs, malicious activity in one VM could not affect all other VMs, so it is necessary to apply security mechanisms in order to improve isolation between VMs. Before applying security policies to a virtualization system, it is necessary to quantitatively measure the hypervisor from isolation point of view aiming at increasing security of isolation among VMs; then considering the circumstances of the VM execution environments and the results of measurements, we can find areas in the virtualization system with the most effective on enhancing isolation. This paper, proposed a semi‐Markov model for evaluation of isolation, by studying the Xen virtualization architecture. We considered certain type of vulnerability that successfully exploiting it can lead to the attacker's malicious codes execution in part of memory address space. We included all three layers in virtualization for the evaluation purpose, because we wanted to consider strength and weakness areas in virtualization system and not just specific layer such as hypervisor, so it can be figured out that improving security in which layer of virtualization is most effective in improving security of isolation, in respect to the increasing or decreasing attacker's (defender's) ability to be successful. The sensitivity analysis results show that MTTSF is more sensitive to the increasing ability of defensive mechanisms to be successful at the application layer and decreasing the attacker's ability to successfully exploit vulnerabilities at the guest operating system layer, model parameters. Copyright © 2015 John Wiley & Sons, Ltd.
Designing multi‐arm multi‐stage clinical trials using a risk–benefit criterion for treatment selection
Authors: Jaki Thomas , Hampson Lisa V.
Published: October 2015

Multi‐arm clinical trials that compare several active treatments to a common control have been proposed as an efficient means of making an informed decision about which of several treatments should be evaluated further in a confirmatory study. Additional efficiency is gained by incorporating interim analyses and, in particular, seamless Phase II/III designs have been the focus of recent research. Common to much of this work is the constraint that selection and formal testing should be based on a single efficacy endpoint, despite the fact that in practice, safety considerations will often play a central role in determining selection decisions. Here, we develop a multi‐arm multi‐stage design for a trial with an efficacy and safety endpoint. The safety endpoint is explicitly considered in the formulation of the problem, selection of experimental arm and hypothesis testing. The design extends group‐sequential ideas and considers the scenario where a minimal safety requirement is to be fulfilled and the treatment yielding the best combined safety and efficacy trade‐off satisfying this constraint is selected for further testing. The treatment with the best trade‐off is selected at the first interim analysis, while the whole trial is allowed to compose of J analyses. We show that the design controls the familywise error rate in the strong sense and illustrate the method through an example and simulation. We find that the design is robust to misspecification of the correlation between the endpoints and requires similar numbers of subjects to a trial based on efficacy alone for moderately correlated endpoints. © 2015 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.
Acyl‐Trafficking During Plant Oil Accumulation
Authors: Chen Guanqun , Woodfield Helen K. , Pan Xue , Harwood John L. , Weselake Randall J.
Published: October 2015

Vegetable oils are an extremely important agricultural commodity. Their use has risen inexorably for the last 50 years and will undoubtedly be even more prevalent in the future. They have a role not only in foodstuffs but also as renewable chemicals. However, our understanding of their metabolism, and particularly its control, is incomplete. In this article we highlight current knowledge and its deficiencies. In particular, we focus on the important role that phosphatidylcholine plays in lipid accumulation and in influencing the quality of the vegetable oils produced.
Sustainable Process for Production of Azelaic Acid Through Oxidative Cleavage of Oleic Acid
Authors: Benessere Vincenzo , Cucciolito Maria E. , De Santis Augusta , Di Serio Martino , Esposito Roberto , Ruffo Francesco , Turco Rosa
Published: October 2015

This work describes two sustainable methods for production and purification of azelaic acid (AA) to replace the current process of ozonolysis of oleic acid (OA). The first proceeds in two steps, coupling smooth oxidation of OA to 9,10‐dihydroxystearic acid (DSA) with subsequent oxidative cleavage by sodium hypochlorite. An alternative methodology is also proposed, using a chemocatalytic system consisting of H2O2/H2WO4 for direct oxidative cleavage of the double bond of OA at 373 K. A convenient technique for separation and purification of azelaic acid is also proposed.
Pediatric orthopaedic lower extremity trauma and venous thromboembolism
Authors: Murphy Robert F. , Naqvi Manahil , Miller Patricia E. , Feldman Lanna , Shore Benjamin J.
Published: October 2015

Purpose

Research on venous thromboembolism events (VTE), such as deep venous thrombosis (DVT) and pulmonary embolism (PE), in pediatric orthopaedic trauma patients is sparse. We describe the incidence in the USA of VTE associated with pediatric lower extremity orthopaedic trauma, and characterize injury patterns and VTE treatment methods.

Methods

The Pediatric Health Information System (PHIS) was queried from 2004 to 2013 using ICD-9 codes for lower extremity fractures (pelvis, femur, tibia, ankle, foot) and dislocations (hip, knee, ankle, subtalar) and VTE. Records were queried for age, diagnoses, and VTE treatment.

Results

During the study period 285,611 clinical encounters reported lower extremity trauma. Of those, 167 patients were simultaneously coded with VTE (99 DVT, 50 PE, 18 combined DVT/PE), to give an incidence of VTE associated with pediatric lower extremity trauma of 0.058 %. Patients were from 39 centers, with an average age of 12.9 years (range 0–19). There were 249 fractures and 21 dislocations, with 25 (15 %) patients sustaining more than one lower extremity injury. The most common fracture locations were the femur/femoral neck (95), tibia/ankle (92), and pelvis (44). 72 % (121/167) of patients were treated with anticoagulation medication, of which the most common was low-molecular-weight heparin (111/167, 66 %).

Conclusions

The incidence of VTE events associated with lower extremity orthopaedic trauma is 0.058 %. Adolescents and polytrauma patients with injuries of the femur/femoral neck, tibia/ankle, and pelvis are more commonly affected. Low-molecular-weight heparin is commonly used to treat VTE in pediatric and adolescent patients.
A Time (Not) Apart: A Lesson in Economic History from Cotton Picking Books
Authors: Logan Trevon D.
Published: October 2015

I use the individual-level records from my own family in rural Mississippi to estimate the agricultural productivity of African Americans in manual cotton picking nearly a century after Emancipation, 1952–1965. On average, the Logan children were more than 95 % as productive as enslaved children from the same region in the late antebellum era, 1850–1860. Gender differences in productivity were smaller than among enslaved children and disappeared by late pubescence. Additional qualitative evidence answers questions about agricultural productivity that cannot be derived from the quantitative data. For example, the method of cotton picking was not the gang-labor system described by some economic historians, but an independent process. The qualitative evidence also shows that economic roles were deeply intertwined with racial identity.
THE DESIGN OF AN OPTIMAL RETROSPECTIVE RATING PLAN
Authors: Chen Xinxiang , Chi Yichun , Tan Ken Seng
Published: October 2015

A retrospective rating plan, whose insurance premium depends upon an insured's actual loss during the policy period, is a special insurance agreement widely used in liability insurance. In this paper, the design of an optimal retrospective rating plan is analyzed from the perspective of the insured who seeks to minimize its risk exposure in the sense of convex order. In order to reduce the moral hazard, we assume that both the insured and the insurer are obligated to pay more for a larger realization of the loss. Under the further assumptions that the minimum premium is zero, the maximum premium is proportional to the expected indemnity, and the basic premium is the only free parameter in the formula for retrospective premium given by Meyers (2004) and that the basic premium is determined in such a way that the expected retrospective premium equates to the expected indemnity with a positive safety loading, we formally establish the relationship that the insured will suffer more risk for a larger loss conversion factor or a higher maximum premium. These findings suggest that the insured prefers an insurance policy with the expected value premium principle, which is a special retrospective premium principle with zero loss conversion factor. In addition, we show that any admissible retrospective rating plan is dominated by a stop-loss insurance policy. Finally, the optimal retention of a stop-loss insurance is derived numerically under the criterion of minimizing the risk-adjusted value of the insured's liability where the liability valuation is carried out using the cost-of-capital approach based on the conditional value at risk.
Indications and Types of Antibiotic Agents Used in 6 Acute Care Hospitals, 2009–2010: A Pragmatic Retrospective Observational Study
Authors: Kelesidis Theodoros , Braykov Nikolay , Uslan Daniel Z. , Morgan Daniel J. , Gandra Sumanth , Johannsson Birgir , Schweizer Marin L. , Weisenberg Scott A. , Young Heather , Cantey Joseph , Perencevich Eli , Septimus Edward , Srinivasan Arjun , Laxminarayan Ramanan
Published: October 2015

BACKGROUND

To design better antimicrobial stewardship programs, detailed data on the primary drivers and patterns of antibiotic use are needed.

OBJECTIVE

To characterize the indications for antibiotic therapy, agents used, duration, combinations, and microbiological justification in 6 acute-care US facilities with varied location, size, and type of antimicrobial stewardship programs.

DESIGN, PARTICIPANTS, AND SETTING

Retrospective medical chart review was performed on a random cross-sectional sample of 1,200 adult inpatients, hospitalized (>24 hrs) in 6 hospitals, and receiving at least 1 antibiotic dose on 4 index dates chosen at equal intervals through a 1-year study period (October 1, 2009–September 30, 2010).

METHODS

Infectious disease specialists recorded patient demographic characteristics, comorbidities, microbiological and radiological testing, and agents used, dose, duration, and indication for antibiotic prescriptions.

RESULTS

On the index dates 4,119 (60.5%) of 6,812 inpatients were receiving antibiotics. The random sample of 1,200 case patients was receiving 2,527 antibiotics (average: 2.1 per patient); 540 (21.4%) were prophylactic and 1,987 (78.6%) were therapeutic, of which 372 (18.7%) were pathogen-directed at start. Of the 1,615 empirical starts, 382 (23.7%) were subsequently pathogen-directed and 1,231 (76.2%) remained empirical. Use was primarily for respiratory (27.6% of prescriptions) followed by gastrointestinal (13.1%) infections. Fluoroquinolones, vancomycin, and antipseudomonal penicillins together accounted for 47.1% of therapy-days.

CONCLUSIONS

Use of broad-spectrum empirical therapy was prevalent in 6 US acute care facilities and in most instances was not subsequently pathogen directed. Fluoroquinolones, vancomycin, and antipseudomonal penicillins were the most frequently used antibiotics, particularly for respiratory indications.

Infect. Control Hosp. Epidemiol. 2015;37(1):70–79
The Epidemiology of Carbapenem-Resistant Klebsiella pneumoniae Colonization and Infection among Long-Term Acute Care Hospital Residents
Authors: Mills John P , Talati Naasha J , Alby Kevin , Han Jennifer H
Published: October 2015

OBJECTIVE

An improved understanding of carbapenem-resistant Klebsiella pneumoniae (CRKP) in long-term acute care hospitals (LTACHs) is needed. The objective of this study was to assess risk factors for colonization or infection with CRKP in LTACH residents.

METHODS

A case-control study was performed at a university-affiliated LTACH from 2008 to 2013. Cases were defined as all patients with clinical cultures positive for CRKP and controls were those with clinical cultures positive for carbapenem-susceptible K. pneumoniae (CSKP). A multivariate model was developed to identify risk factors for CRKP infection or colonization.

RESULTS

A total of 222 patients were identified with K. pneumoniae clinical cultures during the study period; 99 (45%) were case patients and 123 (55%) were control patients. Our multivariate analysis identified factors associated with a significant risk for CRKP colonization or infection: solid organ or stem cell transplantation (OR, 5.05; 95% CI, 1.23–20.8; P=.03), mechanical ventilation (OR, 2.56; 95% CI, 1.24–5.28; P=.01), fecal incontinence (OR, 5.78; 95% CI, 1.52–22.0; P=.01), and exposure in the prior 30 days to meropenem (OR, 3.55; 95% CI, 1.04–12.1; P=.04), vancomycin (OR, 2.94; 95% CI, 1.18–7.32; P=.02), and metronidazole (OR, 4.22; 95% CI, 1.28–14.0; P=.02).

CONCLUSIONS

Rates of colonization and infection with CRKP were high in the LTACH setting, with nearly half of K. pneumoniae cultures demonstrating carbapenem resistance. Further studies are needed on interventions to limit the emergence of CRKP in LTACHs, including targeted surveillance screening of high-risk patients and effective antibiotic stewardship measures.

Infect. Control Hosp. Epidemiol. 2015;37(1):55–60
Waves in Newton’s bucket
Authors: Mougel J. , Fabre D. , Lacaze L.
Published: October 2015

The motion of a liquid in an open cylindrical tank rotating at a constant rate around its vertical axis of symmetry, a configuration called Newton’s bucket, is investigated using a linear stability approach. This flow is shown to be affected by several families of waves, all weakly damped by viscosity. The wave families encountered correspond to: surface waves which can be driven either by gravity or centrifugal acceleration, inertial waves due to Coriolis acceleration which are singular in the inviscid limit, and Rossby waves due to height variations of the fluid layer. These waves are described in the inviscid and viscous cases by means of mathematical considerations, global stability analysis and various asymptotic methods; and their properties are investigated over a large range of parameters $(a,Fr)$, with $a$ the aspect ratio and $Fr$ the Froude number.
Postprandial glycaemic and insulinaemic responses in adults after consumption of dairy desserts and pound cakes containing short-chain fructo-oligosaccharides used to replace sugars
Authors: Lecerf J. M. , Clerc E. , Jaruga A. , Wagner A. , Respondek F.
Published: October 2015

The present studies aimed to evaluate the glycaemic and insulinaemic responses, in healthy adults, to short-chain fructo-oligosaccharides (scFOS) from sucrose used to replace sugars in foods. Two study populations aged 18–50 years were recruited and they consumed dairy desserts or pound cakes containing either standard sugar content or scFOS to replace 30 % of the sugar content. For each study, the two products were tested once under a double-blind and cross-over design with at least 7 d between the two tests. Glucose and insulin were measured using standard methods in blood samples collected with a venous catheter for 120 min during a kinetic test. For the dairy desserts, replacing 30 % of the sugars with scFOS significantly reduced postprandial glycaemic (AUC0–120 min; P = 0·020) and insulinaemic (AUC0–120 min; P = 0·003) responses. For the pound cakes, the glycaemic response was not altered (AUC0–120 min; P =  0·322) while the insulinaemic response tended to be lower (AUC0–120 min; P = 0·067). This study showed that scFOS can be used to replace sugars with the benefit of lowering the postprandial glycaemic response without increasing the insulinaemic response. The effect might be modulated by other parameters (e.g. fat content) of the food matrices.
Monosodium l-glutamate in soup reduces subsequent energy intake from high-fat savoury food in overweight and obese women
Authors: Miyaki Takashi , Imada Toshifumi , Shuzhen Hao Susan , Kimura Eiichiro
Published: October 2015

The umami seasoning, monosodium l-glutamate (MSG), has been shown to increase satiety in normal body weight adults, although the results have not been consistent. The satiety effect of MSG in overweight and obese adults has not been examined yet. The objective of the present study was to investigate the effect of MSG in a vegetable soup on subsequent energy intakes as well as food selection in overweight and obese adult women without eating disorders. A total of sixty-eight overweight and obese women (BMI range: 25·0–39·9 kg/m2), otherwise healthy, were recruited to our study. A fixed portion (200 ml) of control vegetable soup or the same soup with added MSG (0·5 g/100 ml) was provided 10 min before an ad libitum lunch and an ad libitum snack in the mid-afternoon. The control soup had equivalent amount of Na to the soup with added MSG. Energy intakes at the ad libitum lunch and ad libitum snack time after the soup preload were assessed using a randomised, double-blind, two-way cross-over design. The soup with MSG in comparison with the control soup resulted in significantly lower consumption of energy at lunch. The addition of MSG in the soup also reduced energy intake from high-fat savoury foods. The soup with MSG showed lower but no significant difference in energy intake at mid-afternoon. The addition of umami seasoning MSG in a vegetable soup may decrease subsequent energy intake in overweight and obese women who do not have eating disorders.
Aid Is Not Oil: Donor Utility, Heterogeneous Aid, and the Aid-Democratization Relationship
Authors: Bermeo Sarah Blodgett
Published: October 2015

Recent articles conclude that foreign aid, like other nontax resources, inhibits political change in authoritarian regimes. This article challenges both the negative political effects of aid and the similarity of aid to other resources. It develops a model incorporating changing donor preferences and the heterogeneity of foreign aid. Consistent with the model's predictions, an empirical test for the period 1973–2010 shows that, on average, the negative relationship between aid and the likelihood of democratic change is confined to the Cold War period. However, in the post–Cold War period, nondemocratic recipients of particular strategic importance can still use aid to thwart change. The relationship between oil revenue and democratic change does not follow the same pattern over time or across recipients. This supports the conclusion that aid has different properties than other, fungible, resources.