bluuebunny/crossref_metadata_2025 huggingface dataset:
Information security: Designing a stochastic‐network for throughput and reliability
Authors: Schavland Jeffrey , Chan Yupo , Raines Richard A.
Published: July 2009

Todas information and communication network requires a design that is secure to tampering. Traditional performance measures of reliability and throughput must be supplemented with measures of security. Recognition of an adversary who can inflict damage leads toward a game‐theoretic model. Through such a formulation, guidelines for network designs and improvements are derived. We opt for a design that is most robust to withstand both natural degradation and adversarial attacks. Extensive computational experience with such a model suggests that a Nash‐equilibrium design exists that can withstand the worst possible damage. Most important, the equilibrium is value‐free in that it is stable irrespective of the unit costs associated with reliability vs. capacity improvement and how one wishes to trade between throughput and reliability. This finding helps to pinpoint the most critical components in network design. From a policy standpoint, the model also allows the monetary value of information‐security to be imputed. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009
On the exponentially weighted moving variance
Authors: Huwang Longcheen , Wang Yi‐Hua Tina , Yeh Arthur B. , Chen Ze‐Shiang Jason
Published: July 2009

MacGregor and Harris (J Quality Technol 25 (1993) 106–118) proposed the exponentially weighted mean squared deviation (EWMS) and the exponentially weighted moving variance (EWMV) charts as ways of monitoring process variability. These two charts are particularly useful for individual observations where no estimate of variability is available from replicates. However, the control charts derived by using the approximate distributions of the EWMS and EWMV statistics are difficult to interpret in terms of the average run length (ARL). Furthermore, both control charting schemes are biased procedures. In this article, we propose two new control charts by applying a normal approximation to the distributions of the logarithms of the weighted sum of chi squared random variables, which are respectively functions of the EWMS and EWMV statistics. These new control charts are easy to interpret in terms of the ARL. On the basis of the simulation studies, we demonstrate that the proposed charts are superior to the EWMS and EWMV charts and they both are nearly unbiased for the commonly used smoothing constants. We also compare the performance of the proposed charts with that of the change point (CP) CUSUM chart of Acosta‐Mejia (1995). The design of the proposed control charts is discussed. An example is also given to illustrate the applicability of the proposed control charts. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009
Quality risk in outsourcing: Noncontractible product quality and private quality cost information
Authors: Kaya Murat , Özer Özalp
Published: July 2009

This article addresses the concept of quality risk in outsourcing. Recent trends in outsourcing extend a contract manufacturer's (CM's) responsibility to several functional areas, such as research and development and design in addition to manufacturing. This trend enables an original equipment manufacturer (OEM) to focus on sales and pricing of its product. However, increasing CM responsibilities also suggest that the OEM's product quality is mainly determined by its CM. We identify two factors that cause quality risk in this outsourcing relationship. First, the CM and the OEM may not be able to contract on quality; second, the OEM may not know the cost of quality to the CM. We characterize the effects of these two quality risk factors on the firms' profits and on the resulting product quality. We determine how the OEM's pricing strategy affects quality risk. We show, for example, that the effect of noncontractible quality is higher than the effect of private quality cost information when the OEM sets the sales price after observing the product's quality. We also show that committing to a sales price mitigates the adverse effect of quality risk. To obtain these results, we develop and analyze a three‐stage decision model. This model is also used to understand the impact of recent information technologies on profits and product quality. For example, we provide a decision tree that an OEM can use in deciding whether to invest in an enterprise‐wide quality management system that enables accounting of quality‐related activities across the supply chain. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009
An explicit finite‐difference method for the approximate solutions of a generic class of anharmonic dissipative nonlinear media
Authors: Macías‐Díaz Jorge Eduardo
Published: July 2009

We develop an explicit finite‐difference method to approximate solutions of modified, Fermi–Pasta–Ulam media, which consider the presence of parameters, such as external damping, relativistic mass, a coefficient for the nonlinear term, and a coefficient of coupling in the case of discrete systems. We propose discrete expressions to approximate consistently the total energy of the system and the average energy flux, and prove that the discrete rate of change of energy is a consistent estimate of its continuous counterpart. The method is thoroughly tested in the energy domain, and our results show that the method gives an approximately constant energy in the case of conservative systems, which fluctuates within a narrow margin of error that may be attributed to truncation errors. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010
Optimal control of work‐in‐process inventory of a two‐station production line
Authors: Kokangul A. , Khaniyev T. , Cochran J. K.
Published: July 2009

Most production lines keep a minimal level of inventory stock to save storage costs and buffer space. However, the random nature of processing, breakdown, and repair times can significantly affect the efficiency of a production line and force the stocking of work‐in‐process inventory. We are interested in the case when starvation and blockage are preferentially avoided.

In this study, a mathematical model has been developed using asymptotic approximation and simulation that provides asymptotic results for the expected value and the variance of the stock level in a buffer as a function of time. In addition, the functional relationship between buffer capacity and the first stopping time caused by starvation or blockage has been determined. Copyright © 2009 John Wiley & Sons, Ltd.
Dicer is required for proper liver zonation
Authors: Sekine Shigeki , Ogawa Reiko , Mcmanus Michael T , Kanai Yae , Hebrok Matthias
Published: July 2009

A number of genes and their protein products are expressed within the liver lobules in a region‐specific manner and confer heterogeneous metabolic properties to hepatocytes; this phenomenon is known as ‘metabolic zonation’. To elucidate the roles of Dicer, an endoribonuclease III type enzyme required for microRNA biogenesis, in the establishment of liver zonation, we examined the distribution of proteins exhibiting pericentral or periportal localization in hepatocyte‐specific Dicer1 knockout mouse livers. Immunohistochemistry showed that the localization of pericentral proteins was mostly preserved in Dicer1‐deficient livers. However, glutamine synthetase, whose expression is normally confined to a few layers of hepatocytes surrounding the central veins, was expressed in broader pericentral areas. Even more striking was the observation that all the periportal proteins that were examined, including phosphoenolpyruvate carboxykinase, E‐cadherin, arginase 1, and carbamoyl phosphate synthetase‐I, lost their localized expression patterns and were diffusely expressed throughout the entire lobule. Thus, with regard to periportal protein expression, the consequences of Dicer loss were similar to those caused by the disruption of β‐catenin. An analysis of livers deficient in β‐catenin did not identify the down‐regulation of Dicer1 or any microRNAs, indicating that they are not directly activated by β‐catenin. Thus, the present study illustrates that Dicer plays a pivotal role in the establishment of liver zonation. Dicer is essential for the suppression of periportal proteins by Wnt/β‐catenin/TCF signalling, albeit it likely acts in an indirect manner. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Erythrocytapheresis in children with sickle cell disease and acute chest syndrome
Authors: Velasquez M. Paulina , Mariscalco Mary M. , Goldstein Stuart L. , Airewele Gladstone E.
Published: July 2009

Background

Red cell exchange (RCE) is part of the management of acute chest syndrome (ACS) in patients with sickle cell disease. The study describes the indications and outcome of the procedure.

Procedure

We retrospectively reviewed 53 episodes of ACS in 44 patients who received RCE from January 2003 to October 2006. Patients were aged between 18 months and 19 years.

Results

Sixty‐two percent of the patients had at least one previous episode of ACS. ACS was diagnosed at presentation in 66%, in the remainder ACS was diagnosed after a median of 2 days. Clinical Respiratory Score (CRS) was assigned retrospectively to assess respiratory distress (0 = no distress, >6 = severe). Median admission CRS of 2, progressed to 4 before RCE and declined to 2 within 24 hr afterwards. Median day of RCE was day 2 (IQR 1–3) and the main indication was worsening respiratory distress. No patient developed venous thrombosis, alloantibodies or other complications from RCE. Median length of hospitalization was 7 days (IQR: 5–9 days). Patients with a platelet count significantly lower than their baseline on admission had an increased risk of mechanical ventilation.

Conclusions

RCE appears to be a safe and effective treatment for patients with sickle cell disease and ACS. One‐third of patients who received RCE for ACS had no respiratory symptoms on admission. Pediatr Blood Cancer 2009;53:1060–1063. © 2009 Wiley‐Liss, Inc.
The problematic art of conversation: Communication and health practice evolution
Authors: Walsh Kenneth , Jordan Zoe , Apolloni Lucia
Published: July 2009

Conversation is an important part of everyday life and is increasingly recognized as being critical to the success of practice change initiatives in the health care environment. However, conversation is becoming something of a lost art and it is important that we consciously ‘create the space’ to have constructive, meaningful and inclusive conversations in and around health practices.

This article explores the importance of conversation to organizational functioning, and the potential for practice development to facilitate meaningful conversations around clinical practice and practice change. It also discusses a form of conversation called future‐focused conversation as one approach to assist cultural evolution in health environments. Copyright © 2009 John Wiley & Sons, Ltd.
Non‐aspirin NSAIDs, cyclooxygenase‐2 inhibitors and risk for cardiovascular events–stroke, acute myocardial infarction, and death from coronary heart disease
Authors: Roumie Christianne L. , Choma Neesha N. , Kaltenbach Lisa , Mitchel, Jr Edward F. , Arbogast Patrick G. , Griffin Marie R.
Published: July 2009

Purpose

To determine if certain non‐steroidal anti‐inflammatory drugs (NSAIDs) are associated with increased risk of cardiovascular events: acute myocardial infarction (AMI), stroke, and death from coronary heart disease (CHD).

Methods

We conducted a retrospective cohort study of Tennessee Medicaid enrollees aged 35–94 years between 1 January 1999 and 31 December 2005. Eligible persons were non‐institutionalized, had continuous enrollment, and had no serious illness prior to cohort entry. Exposure to celecoxib, rofecoxib, valdecoxib, ibuprofen, naproxen, diclofenac, and indomethacin was studied. The outcome was hospitalization for AMI, stroke, or death from CHD among those with and without a history of cardiovascular disease (CVD). Adjusted hazard ratios (aHR) and 95% confidence intervals (95% CI) are reported.

Results

There were 610 001 persons in the final cohort and 14% had a baseline history of CVD. In those without CVD (N = 525 249) there were 1 566 678 person‐years of follow‐up and 12 184 events. In this group, non‐users had 7.90 events/1000 person‐years. Events/1000 person‐years were 10.41 for current use of celecoxib (aHR 1.00, 95% CI 0.89–1.13), 10.91 for rofecoxib (aHR 1.21, 95% CI 1.07–1.37), 12.46 for valdecoxib (aHR 1.30 95% CI 1.04–1.61), and 13.25 for indomethacin (aHR 1.36, 95% CI 1.11–1.66) compared to non‐users. Among patients with a past history of CVD (N = 84 752) there were 397 977 person‐years of follow‐up and 10 248 events. Non‐users had 28.30 events/1000 person‐years. Among those with CVD, rofecoxib use was associated with increased event rate (30.28 events/1000 person‐years [aHR 1.21, 95% CI 1.08–1.37]) and naproxen was associated with a decreased event rate (22.66 events/1000 person‐years [aHR 0.88, 95% CI 0.79–0.99]). Among new users, the results were similar except risk among naproxen users was no longer different than non‐users.

Conclusions

We found an increased risk of cardiovascular events among all and new current users of rofecoxib, valdecoxib, and indomethacin in patients with no history of CVD. Among patients with CVD, all and new current rofecoxib use was associated with an increased risk of a cardiovascular event. Copyright © 2009 John Wiley & Sons, Ltd.
Proteomic profiling of the prechylomicron transport vesicle involved in the assembly and secretion of apoB‐48‐containing chylomicrons in the intestinal enterocytes
Authors: Wong Diana M. , Webb Jennifer P. , Malinowski Paul M. , Macri Joseph , Adeli Khosrow
Published: July 2009

Intracellular assembly of chylomicrons (CM) occurs in intestinal enterocytes through a series of complex vesicular interactions. CM are transported from the ER to the Golgi using a specialized vesicular compartment called the prechylomicron transport vesicle (PCTV). In this study, PCTVs were isolated from the enteric ER of the Syrian Golden hamster, and characterized using 2‐DE and MS. Proteomic profiles of PCTV‐associated proteins were developed with the intention of identifying proteins involved in the formation, transport, lipidation, and assembly of CM particles. Positively identified proteins included those involved in lipoprotein assembly, namely microsomal triglyceride transfer protein and apolipoprotein B‐48, as well as proteins involved in vesicular transport, such as Sar1 and vesicle‐associated membrane protein 7. Other groups of proteins found were chaperones, intracellular vesicular trafficking proteins, fatty acid‐binding proteins, and lipid‐related proteins. These findings have increased our understanding of the transport vesicle involved in the intracellular assembly and transport of CM and can provide insight into potential cellular factors responsible for dysregulation of intestinal CM production.
Proteomics‐based identification of two novel direct targets of hypoxia‐inducible factor‐1 and their potential roles in migration/invasion of cancer cells
Authors: Liao Shi‐Hua , Zhao Xu‐Yun , Han Yu‐Hui , Zhang Jing , Wang Li‐Shun , Xia Li , Zhao Ke‐Wen , Zheng Ying , Guo Meng , Chen Guo‐Qiang
Published: July 2009

Hypoxia‐inducible factor‐1 (HIF‐1), consisting of oxygen‐sensitive HIF‐1α and constitutively expressed HIF‐1β subunits, is a master transcriptional activator for cellular response to hypoxia. To explore direct HIF‐1 targets, here we used differential gel electrophoresis (DIGE) to compare the HIF‐1‐regulated proteins between leukemic U937T‐cell line with and without conditional induction of HIF‐1α protein by tetracycline‐off system. Among the upregulated proteins identified, mRNA levels of annexin A1, macrophage‐capping protein (CapG), S100 calcium‐binding protein A4 (S100A4), S100A11, acyl‐CoA‐binding protein and calcyclin‐binding protein also increased. The expressions of the annexin A1, CapG and S100A4 genes were significantly induced by hypoxia in five adherent cell lines tested besides U937 cells, while their expressions were blocked by the short hairpin RNA specifically against HIF‐1α. Further luciferase reporter assay and chromatin immunoprecipitation showed that HIF‐1α directly bound to three hypoxia‐responsive elements located at intron 1 of S100A4 gene and hypoxia‐responsive element at −350 to −346 of CapG gene, which are essential for HIF‐1‐induced expression. Additionally, the role of S100A4 expression in migration and invasion of cancer cells were also confirmed. These findings would provide new sights for understanding the molecular mechanisms underlying HIF‐1 action.
Photonic immobilization of high‐density protein arrays using Fourier optics
Authors: Skovsen Esben , Kold Ane B. , Neves‐Petersen Maria Teresa , Petersen Steffen B.
Published: July 2009

The technique of UV‐light‐assisted immobilization of disulfide containing proteins has been combined with the Fourier‐transforming properties of lenses as well as with a simple millimeter scale feature size spatial mask. The result is a new simple and inexpensive way of creating high‐density protein arrays with feature sizes down to a few hundred nanometers, which represents an improvement of tenfold over existing commercially available high‐density protein arraying methods.
Calpain‐truncated CRMP‐3 and ‐4 contribute to potassium deprivation‐induced apoptosis of cerebellar granule neurons
Authors: Liu Wei , Zhou Xing‐wang , Liu Shaojun , Hu Kunhua , Wang Chong , He Qingyu , Li Mingtao
Published: July 2009

Increasing evidence shows that calpain‐mediated proteolytic processing of a selective number of proteins plays an important role in neuronal apoptosis. Study of calpain‐mediated cleavage events and related functions may contribute to a better understanding of neuronal apoptosis and neurodegenerative diseases. We, therefore, investigated the role of calpain substrates in potassium deprivation‐induced apoptosis of cerebellar granule neurons (CGNs). Twelve previously known and seven novel candidates of calpain substrates were identified by 2‐D DIGE and MALDI‐TOF/TOF MS analysis. Further, the identified novel calpain substrates were validated by Western blot analysis. Moreover, we focused on the collapsin response mediator proteins (CRMP‐1, ‐2, ‐3 and ‐4 isoforms) and found that CRMPs were proteolytically processed by calpain but not by caspase, both in vivo and in vitro. To clarify the properties of the calpain‐mediated proteolysis of CRMPs, we constructed the deletion mutants of CRMPs for additional biochemical studies. In vitro cleavage assays revealed that CRMP‐1, ‐2 and ‐4 were truncated by calpain at the C‐terminus, whereas CRMP‐3 was cleaved at the N‐terminus. Finally, we assessed the role of CRMPs in the process of potassium deprivation‐triggered neuronal apoptosis by overexpressing the truncated CRMPs in CGNs. Our data clearly showed that the truncated CRMP‐3 and ‐4, but not CRMP‐1 and ‐2, significantly induced neuronal apoptosis. These findings demonstrated that calpain‐truncated CRMP‐3 and ‐4 act as pro‐apoptotic players when CGNs undergo apoptosis.
Accurate quantitation of standard peptides used for quantitative proteomics
Authors: Bordeerat Narisa K. , Georgieva Nadia I. , Klapper David G. , Collins Leonard B. , Cross Tyra J. , Borchers Christoph H. , Swenberg James A. , Boysen Gunnar
Published: July 2009

MS‐based proteomics has become an indispensable tool in system biology generating a need for accurate and precise quantitation of peptide standards. The presented method utilizes ultra performance LC‐MS/MS (UPLC‐MS/MS) to accurately quantify peptide standards at concentrations of 0.1–10 μM. The ability for accurate quantitation of micro‐molar concentrations has the advantages that quantitation can be performed routinely with high precision and the high sensitivity of the method minimizes the amounts required.
Proteomic profiling of PrP27‐30‐enriched preparations extracted from the brain of hamsters with experimental scrapie
Authors: Giorgi Alessandra , Di Francesco Laura , Principe Serena , Mignogna Giuseppina , Sennels Lau , Mancone Carmine , Alonzi Tonino , Sbriccoli Marco , De Pascalis Angela , Rappsilber Juri , Cardone Franco , Pocchiari Maurizio , Maras Bruno , Schininà M. Eugenia
Published: July 2009

Transmissible spongiform encephalopathies (TSEs) are neurodegenerative disorders characterized by the accumulation in the CNS of a pathological conformer (PrPTSE) of the host‐encoded cellular prion protein (PrPC). PrPTSE has a central role in the pathogenesis of the disease but other factors are likely involved in the pathological process. In this work we employed a multi‐step proteomic approach for the identification of proteins that co‐purify with the protease‐resistant core of PrPTSE (PrP27‐30) extracted from brains of hamsters with experimental scrapie. We identified ferritin, calcium/calmodulin‐dependent protein kinase α type II, apolipoprotein E, and tubulin as the major components associated with PrP27‐30 but also trace amounts of actin, cofilin, Hsp90α, the γ subunit of the T‐complex protein 1, glyceraldehyde 3‐phosphate dehydrogenase, histones, and keratins. Whereas some of these proteins (tubulin and ferritin) are known to bind PrP, other proteins (calcium/calmodulin‐dependent protein kinase α type II, Hsp90α) may associate with PrPTSE fibrils during disease. Apolipoprotein E and actin have been previously observed in association with PrPTSE, whereas cofilin and actin were shown to form abnormal rods in the brain of patients with Alzheimer disease. The roles of these proteins in the development of brain lesions are still unclear and further work is needed to explain their involvement in the pathogenesis of TSEs.
Getting a grip on proteomics data – Proteomics Data Collection (ProDaC)
Authors: Eisenacher Martin , Martens Lennart , Hardt Tanja , Kohl Michael , Barsnes Harald , Helsens Kenny , Häkkinen Jari , Levander Fredrik , Aebersold Ruedi , Vandekerckhove Joël , Dunn Michael J. , Lisacek Frederique , Siepen Jennifer A. , Hubbard Simon J. , Binz Pierre‐Alain , Blüggel Martin , Thiele Herbert , Cottrell John , Meyer Helmut E. , Apweiler Rolf , Stephan Christian
Published: July 2009

In proteomics, rapid developments in instrumentation led to the acquisition of increasingly large data sets. Correspondingly, ProDaC was founded in 2006 as a Coordination Action project within the 6th European Union Framework Programme to support data sharing and community‐wide data collection. The objectives of ProDaC were the development of documentation and storage standards, setup of a standardized data submission pipeline and collection of data. Ending in March 2009, ProDaC has delivered a comprehensive toolbox of standards and computer programs to achieve these goals.
Nature of the transient species formed in the pulse radiolysis of 4‐hydroxybenzyl alcohol in aqueous solutions: observation of equilibrium in the reaction of OH‐adducts with HPO ions
Authors: Dhiman Surajdevprakash B. , Naik Devidas B.
Published: July 2009

Reactions of .OH/O.− radicals, H‐atoms as well as specific oxidants such as N and Cl radicals with 4‐hydroxybenzyl alcohol (4‐HBA) in aqueous solutions have been investigated at various pH values using the pulse radiolysis technique. At pH 6.8, .OH radicals were found to react with 4‐HBA (k = 6 × 109 dm3 mol−1 s−1) mainly by contributing to the phenyl moiety and to a minor extent by H‐abstraction from the CH2OH group. .OH radical adduct species of 4‐HBA, i.e., .OH‐(4‐HBA) formed in the addition reaction were found to undergo dehydration to give phenoxyl radicals of 4‐HBA. Decay rate of the adduct species was found to vary with pH. At pH 6.8, decay was very much dependent on phosphate buffer ion concentrations. Formation rate of phenoxyl radicals was found to increase with phosphate buffer ion concentration and reached a plateau value of 1.6 × 105 s−1 at a concentration of 0.04 mol dm−3 of each buffering ion. It was also seen that .OH‐(4‐HBA) adduct species react with HPO ions with a rate constant of 3.7 × 107 dm3 mol−1 s−1 and there was no such reaction with H2PO ions. However, the rate of reaction of .OH‐(4‐HBA) adduct species with HPO ions decreased on adding KH2PO4 to the solution containing a fixed concentration of Na2HPO4 which indicated an equilibrium in the H+ removal from .OH‐(4‐HBA) adduct species in the presence of phosphate ions. In the acidic region, the .OH‐(4‐HBA) adduct species were found to react with H+ ions with a rate constant of 2.5 × 107 dm3 mol−1 s−1. At pH 1, in the reaction of .OH radicals with 4‐HBA (k = 8.8 × 109 dm3 mol−1 s−1), the spectrum of the transient species formed was similar to that of phenoxyl radicals formed in the reaction of Cl radicals with 4‐HBA at pH 1 (k = 2.3 × 108 dm3 mol−1 s−1) showing that .OH radicals quantitatively bring about one electron oxidation of 4‐HBA. Reaction of .OH/O.− radicals with 4‐HBA by H‐abstraction mechanism at neutral and alkaline pH values gave reducing radicals and the proportion of the same was determined by following the extent of electron transfer to methyl viologen. H‐atom abstraction is the major pathway in the reaction of O.− radicals with 4‐HBA compared to the reaction of .OH radicals with 4‐HBA. At pH 1, transient species formed in the reactions of H‐atoms with 4‐HBA (k = 2.1 × 109 dm3 mol−1 s−1) were found to transfer electrons to methyl viologen quantitatively. Copyright © 2009 John Wiley & Sons, Ltd.
Intramolecular Diels–Alder reaction in enyne–allenes: a computational investigation and comparison with the Myers–Saito and Schmittel reactions
Authors: Chen Hsin‐Tsung , Chen Hui‐Lung , Ho Jia‐Jen
Published: July 2009

The reaction mechanisms as well as substituted effect and solvent effect of the enyne–allenes are investigated by Density Functional Theory (DFT) method and compared with the Myers–Saito and Schmittel reactions. The Myers–Saito reaction of non‐substituted enyne–allenes is kinetically and thermodynamically favored as compared to the Schmittel reaction; while the concerted [4 + 2] cycloaddition is only 1.32 kcal/mol higher than the C2C7 cyclization and more exothermic (ΔRE = −69.38 kcal/mol). For R1 = CH3 and t‐Bu, the increasing barrier of the C2C7 cyclization is higher than that for the C2C6 cyclization because of the steric effect, so the increased barrier of the [4 + 2] cycloaddition is affected by such substituted electron‐releasing group. Moreover, the strong steric effect of R1 = t‐Bu would shift the C2C7 cyclization to the [4 + 2] cycloaddition. On the other hand, for R1 = Ph, NH2, O−, NO2, and CN substituents, the barrier of the C2C6 cyclization would be more diminished than the C2C7 cyclization due to strong mesomeric effect; the reaction path of C2C7 cyclization would also shift to the [4 + 2] cycloaddition. The solvation does not lead to significant changes in the potential‐energy surface of the reaction except for the more polar surrounding solvent such as dimethyl sulfoxide (DMSO), or water. Copyright © 2009 John Wiley & Sons, Ltd.
Impact of alopecia and scalp cooling on the well‐being of breast cancer patients
Authors: van den Hurk Corina J. G. , Mols Floortje , Vingerhoets Ad J. J. M. , Breed Wim P. M.
Published: July 2009

Objective: Chemotherapy‐induced alopecia, a common and distressing side effect of chemotherapy, may be prevented by scalp cooling, which reduces toxicity of cytostatics in hair root cells. This is the first study designed to assess the effect of scalp cooling on well‐being.

Methods: A prospective multi‐centre study was performed in 13 hospitals. Breast cancer patients treated with (N=98) and without (N=168) scalp cooling completed questionnaires (EORTC QLQ‐C30 and EORTC‐QLQ‐BR23, BIS, MBA, HADS) before chemotherapy, and three weeks and six months after the last chemotherapy cycle.

Results: Scalp cooling was effective in 52% of the cases. Alopecia was considered among the most distressing problems at all three moments of measurement. A trend towards higher well‐being was found in successfully scalp‐cooled patients, as indicated by a general better health‐related quality of life and better body image, whereas unsuccessfully scalp‐cooled patients reported lowest well‐being.

Conclusions: Scalp cooling contributes not only to the well‐being of successfully scalp‐cooled patients but also seems to cause additional distress when patients lose their hair despite scalp cooling. This might be related to disappointment due to alopecia despite scalp cooling or possibly to a general higher biological availability of cytostatics. We recommend additional support for patients when scalp cooling is not successful and to spend more effort to maximise the effectiveness of scalp cooling. Copyright © 2009 John Wiley & Sons, Ltd.
Ice‐wedge pseudomorphs and frost‐cracking structures in Weichselian sediments, central‐west Poland
Authors: Ewertowski Marek
Published: July 2009

Wedge‐shaped structures are described from three sites in the central Wielkopolska region (central‐west Poland) in two main positions: (1) within fluvioglacial deposits below the Weichselian subglacial till and (2) within recessional deposits above this subglacial till. The wedges are interpreted as ice‐wedge pseudomorphs (Rensko site), relict frost cracks (Tomice site) and thermokarst‐affected ice‐wedge pseudomorphs (Annowo‐Kiszkowo area). The pseudomorphs suggest that thermal‐contraction cracking occurred in the region in front of the advancing Weichselian ice sheet, as well as following its recession. Frost structures, which are interpreted as having degraded slowly, were much more affected by thermokarst processes (Annowo‐Kiszkowo area) than those in the Rensko and Tomice sites which probably thawed rapidly, due to an insulating and warming effect of the overlying ice masses. The development of ice wedges was influenced by wet conditions in former depressions between ice‐cored ridges or by large amounts of meltwater in the proglacial environment. These periglacial features support previous hypotheses that climatic conditions in the Wielkopolska region after the last ice‐sheet recession changed gradually from glacial to periglacial. Copyright © 2009 John Wiley & Sons, Ltd.
Combined structural and optical studies of stacking faults in 4H‐SiC layers grown by chemical vapour deposition
Authors: Marinova Maya , Robert Teddy , Juillaguet Sandrine , Tsiaoussis Ioannis , Frangis Nikolaos , Polychroniadis Efstathios , Camassel Jean , Chassagne Thierry
Published: July 2009

The formation of in‐grown stacking faults (SFs) in chemical vapour deposition (CVD) grown 4H‐SiC epilayer has been studied by high‐resolution transmission electron microscopy (HRTEM) and low‐temperature photoluminescence (LTPL). Local inhomogeneities in the SF density have been found, where different SF arrangements appear. They range from pure 8H‐SiC unit cells to a few distinguished sequences, forming in some cases long‐range semi‐periodic incommensurate structures. Despite such large dispersion, the same optical (LTPL) signature is always found. This is discussed in the light of coupled quantum well models.

magnified image

HRTEM image showing the formation of an extended defect (16 bilayers thick) in a CVD grown 4H‐SiC epitaxial layer.
Structural changes and peculiarities of NiPdSi formation investigated by Raman and Auger spectroscopy
Authors: Karabko Aliaksandra , Dostanko Anatoly , Kong JinFang , Shen Wenzhong
Published: July 2009

In this contribution we report on peculiarities of formation, structural and vibrational properties of compositional (alloying) nickel silicides such as NiPdSi. MicroRaman analysis has shown that NiPdSi films are thermally stable up to 900 °C, which is by 100 °C higher than that for pure NiSi films. Using Miedema's model we have calculated the heat of formation for NiPdSi to be by 4 kJ mol−1 smaller than that for pure NiSi. This demonstrates an essential role of Pd in the enhancement of thermal stability of NiSi and in retardation of NiSi2 phase formation. Raman spectra registered for NiPdSi show the peaks at wavenumbers typical for NiSi, although red shifted, as well as new Raman peaks at 322 and 434 cm−1 reported recently in [Karabko et al. J. Appl. Phys. 105, 033518 (2009)]. We have assigned these two peaks to the compositional disorder, introduced by the presence of Pd alloy. By means of Auger electron spectroscopy (AES) we have determined the peculiarities of the element distribution and Pd diffusion in NiPdSi and NiSi films, which results in a slight lack of silicon in the stoichiometry of phases and exponential decay law of Pd distribution with temperature.
Multi‐layer thickness determination using differential‐based enhanced Fourier transforms of X‐ray reflectivity data
Authors: Poust Benjamin , Sandhu Rajinder , Goorsky Mark
Published: July 2009

Layer thickness determination of single and multi‐layer structures is achieved using a new method for generating Fourier transforms (FTs) of X‐ray reflectivity data. This enhanced Fourier analysis is compared to other techniques in the determination of AlN layer thickness deposited on sapphire. In addition to demonstrably improved results, the results also agree with thicknesses determined using simulations and TEM measurements. The effectiveness of the technique is further demonstrated using the more complicated metamorphic epitaxial multi‐layer AlSb/InAs structures deposited on GaAs. The approach reported here is based upon differentiating the specular intensity with respect to the vertical reciprocal space coordinate QZ. In general, differentiation is far more effective at removing the sloping background present in reflectivity scans than logarithmic compression alone, average subtraction alone, or other methods. When combined with any of the other enhancement techniques, however, differentiation yields distinguishable discrete Fourier transform (DFT) power spectrum peaks for even the weakest and most truncated of sloping oscillations that are present in many reflectivity scans from multi‐layer structures.
Resistance switching properties of epitaxial Pr0.7Ca0.3MnO3 thin films with different electrodes
Authors: Lau H. K. , Leung C. W. , Chan Y. K.
Published: July 2009

Resistance switching effect caused by external electric field was investigated in Pr0.7Ca0.3MnO3 (PCMO) thin films grown on (001)‐oriented LaAlO3, by using different metallic (Al, Pt, Au, Ti) electrodes. When Al was used as one or both of the electrodes, PCMO thin films exhibited resistance changes upon reversing voltage polarities. Nonlinear, hysteretic current–voltage loops were observed. Our measurements showed that the total resistance of the samples were dominated by interfacial resistance. Such kind of device structure can find applications in non‐volatile memory devices.
Dependence on substrate temperature of the conformation and structure of a poly[3‐(4‐octyloxyphenyl)thiophene] (POOPT) thin film obtained by matrix assisted pulsed laser evaporation (MAPLE)
Authors: Califano Valeria , Bloisi Francesco , Vicari Luciano , Cassinese Antonio , Barra Mario , Carella Antonio , Roviello Antonio
Published: July 2009

In this paper, the substrate temperature influence on the structural and main opto‐electronic properties of poly[3‐(4‐octyloxyphenyl)thiophene] (POOPT) films, deposited by matrix assisted pulsed laser evaporation (MAPLE), was analyzed. Fourier transform infrared analysis of films was performed to verify that laser irradiation has not induced polymer modifications or decomposition, confirming the reliability and high control of the MAPLE deposition technique. UV–Visible spectroscopy allowed gaining insights about films conformation and packing, while conductivity values have been measured by basic current–voltage measurements. In agreement with the experimental observations reported for other growth techniques, our results highlight the substrate temperature effect in promoting the film structural organization and improving their charge transport capability. At substrate temperature of 453 K, films deposited by MAPLE show a higher conjugation length in comparison with spin‐coated films. The substrate temperature increase also favors side‐chains commutation to different steric configurations.
Electrical, structural and optical characterization of copper oxide thin films as a function of post annealing temperature
Authors: Figueiredo V. , Elangovan E. , Gonçalves G. , Franco N. , Alves E. , Park S.H.K. , Martins R. , Fortunato E.
Published: July 2009

Copper oxide thin films were obtained by annealing (temperature ranging between 100 and 450 °C) the metallic Cu films deposited on glass substrates by e‐beam evaporation. XRD studies confirmed that the cubic Cu phase of the as‐deposited films changes into single cubic Cu2O phase and single monoclinic CuO phase, depending on the annealing conditions. The crystallite size is varied between ∼12 and 31 nm. The lattice parameters of cubic Cu and Cu2O phases are estimated to ∼3.60 and ∼4.26 Å, respectively. The films with Cu2O phase showed p‐type characteristics. The conductivity is decreased linearly with the decreasing temperature (1/T), which has confirmed the semiconductor nature of the deposited films. The calculated activation energy is varied between 0.10 and 0.16 eV. The surface microstructure is changed depending on the variation in the annealing temperature. The poor transmittance of the as‐deposited films (<1%) is increased to a maximum of ∼80% (800 nm) on annealing at 200 °C. The estimated direct allowed band gap is varied between 1.73 and 2.89 eV.
Spatially resolved contact‐resistance measurements on crystalline silicon solar cells
Authors: Kontermann Stefan , Hörteis Matthias , Ruf Alexander , Feo Sergio , Preu Ralf
Published: July 2009

This paper demonstrates a method for quantitatively determining the spatially resolved contact resistance of silicon solar cells. Contact‐resistance maps obtained by this technique on screen‐printed industrial silicon solar cells are presented and discussed. Extending the contact‐resistance map to a series‐resistance map by adding contributions from the rear, bulk, emitter, and metallization shows this map to qualitatively agree well with photoluminescence (PL) series‐resistance imaging. Compared to existing approaches, our technique enables the spatially resolved measurement of the contact resistance separately from any other series‐resistance contributions.
Role of oxygen additive on hydrogen impurity incorporation in nanocrystalline diamond films fabricated by microwave plasma chemical vapor deposition
Authors: Tang C. J. , Gu L. P. , Grácio J. , Ribeiro J. L.
Published: July 2009

In this work, we study the influence of oxygen additive in the gas phase on hydrogen impurity incorporation into thick nanocrystalline diamond (NCD) films. Various diamond samples were grown on large silicon wafers of 5.08 cm diameter by adjusting the amount of oxygen and nitrogen additives into a conventional CH4/H2 plasma while keeping the other parameters constant using a 5‐kW microwave plasma‐assisted chemical vapor deposition (MPCVD) reactor. The morphology, crystalline quality, and hydrogen impurity content of the produced diamond samples were characterized using scanning electron microscopy, micro‐Raman spectroscopy, and Fourier transform infrared (FTIR) spectroscopy, respectively. The Raman and the FTIR spectra of the diamond samples indicate that on increasing the amount of oxygen additive in the gas phase, the crystalline quality of the NCD films is significantly enhanced, while their bonded hydrogen content decreases drastically. We conclude that a small amount of oxygen addition has an enhancement effect on the overall quality of diamond films ranging from polycrystalline to nanocrystalline in two ways: improving the diamond crystalline quality and suppressing hydrogen impurity incorporation.
Fabrication and optical properties of thin silica‐coated CdSe/ZnS quantum dots
Authors: Sun Ye , Masia Francesco , Langbein Wolfgang , Borri Paola
Published: July 2009

We demonstrate the fabrication of thin silica‐coated CdSe/ZnS colloidal quantum dots using a reverse microemulsion method. Spherical particles of <20 nm diameter with a single dot in the centre of a thin silica shell of good morphology are achieved, promising for biophotonic applications where hydrophilic bio‐compatible and small luminescent nanoparticles are needed. We characterize the spectrally‐ and time‐resolved photoluminescence of these silica‐coated dots, from which we identify the influence of each step of the coating procedure on their emission quantum yield. Optimization of the growth parameters eventually results in a less than two‐fold reduction of the quantum yield after silica‐coating.
Photoplastic effects in chalcogenide glasses: A review
Authors: Yannopoulos S. N. , Trunov M. L.
Published: July 2009

A synopsis of various photoinduced changes of rheological, mechanical and elastic properties is presented in the first part of the article. After a critical appraisal of a large body of experimental data, it is suggested that the photoviscous effect, that is, the athermal decrease of viscosity of a non‐crystalline chalcogenide upon illumination, is the key for a plethora of photoinduced effects reported so far in the literature under different names. Morphic effects (shape or surface morphology) may appear either in the presence or absence of external mechanical stimuli leading to the fabrication of a variety of technologically important photoprocessed structures. A few representative examples of photoplastic effects are described in some detail in the second part of the paper, based on information provided by in situ Raman scattering and nanoindentation experiments.
On the atomic structure of thin amorphous Ge–Sb–Te films
Authors: Frumar Miloslav , Kohoutek Tomas , Prikryl Jan , Orava Jiri , Wagner Tomas
Published: July 2009

The structure of thin films of Ge2Sb2Te5 was studied by high‐resolution transmission electron microscopy (HRTEM) and by X‐ray diffraction (XRD). The as‐evaporated films prepared by flash evaporation were amorphous. Nearly, all the atoms were randomly distributed but even in as‐evaporated films small areas with some ordering were noticeable. The number and size of the ordered areas increased with thermal treatment of films to temperatures ∼80 °C, i.e., ∼70 °C below the crystallization temperature of amorphous Ge2Sb2Te5. After thermal treatment, small embryos of nucleation centers (size <8 nm) were formed. According to XRD measurements the films as a whole were still fully amorphous. The crystallite model of the structure of amorphous solids is then partly valid, at least for Ge2Sb2Te5. We expect that it can be applied also for other Ge–Sb–Te‐based films, as well as for the other amorphous chalcogenides. The possible impact of the formation of nucleation “embryos” on storage time of data in optical and electrical phase‐change memory materials and devices is discussed.
Garcinia mangostana L.: a phytochemical and pharmacological review
Authors: Obolskiy Dmitriy , Pischel Ivo , Siriwatanametanon Nisarat , Heinrich Michael
Published: July 2009

Garcinia mangostana L. (mangosteen, Clusiaceae) has a long history of use as a medical plant, mostly in Southeast Asia. This is a review of the phytochemistry and pharmacology of mangosteen. Traditionally mangosteen is famous for its antiinflammatory properties and is used in the treatment of skin infections and wounds. Other applications include the therapy of various conditions such as dysentery, different urinary disorders, cystitis and gonorrhoea. This review highlights the development of this botanical drug into a widely used nutraceutical. Products derived from G. mangostana are now distributed increasingly all over the world. This has given rise to a concomitant increase in research on the phytochemical constituents and biological activity of mangosteen. Central to the biological activity of the species are xanthones which are reviewed in detail. A comprehensive assessment of the biological activities of individual xanthones as well as extracts of G. mangostana is included. In addition, its potential in terms of developing novel drug leads is assessed. Products containing its fruits are now sold widely as ‘liquid botanical supplements’, but evidence for the health benefits of these products is still lacking. As shown here, a serious weakness in our knowledge is the lack of clinical data and it is not yet clear to what extent the findings about pharmacological activities are of potential clinical relevance. Copyright © 2009 John Wiley & Sons, Ltd.
A comparison of CUSUM, EWMA, and temporal scan statistics for detection of increases in poisson rates
Authors: Han Sung Won , Tsui Kwok‐Leung , Ariyajunya Bancha , Kim Seoung Bum
Published: July 2009

Various control chart methods have been used in healthcare and public health surveillance to detect increases in the rates of diseases or their symptoms. Although the observations in many health surveillance applications are often discrete, few efforts have been made to ex‐ plore the behavior of detection methods in discrete distributions. Joner et al. (Statist. Med. 2008; 27:2555–2575) investigated and compared the performance of the scan statistic methods with the cumulative sum (CUSUM) charts under a Bernoulli distribution. In this paper we compare the performance of three detection methods: temporal scan statistic, CUSUM, and exponential weighted moving average (EWMA) when the observations follow the Poisson distribution. A simulation study showed that the Poisson CUSUM and EWMA charts generally outperformed the Poisson scan statistic methods. In comparisons between CUSUM and EWMA, the CUSUM charts were superior in dealing with a large shift with a later change in time. However, the EWMA charts outperformed the CUSUM charts in situations with a small shift and an early change in time. The methods were also compared with thyroid cancer using a real data set. Copyright © 2009 John Wiley & Sons, Ltd.
Similarity Based Descriptors – Useful for Classification of Substrates of the Human Multidrug Transporter P‐Glycoprotein?
Authors: Schwaha Rita , Ecker Gerhard F.
Published: July 2009

As part of the ATP‐binding cassette transporter superfamily P‐glycoprotein (ABCB1) acts as xenotoxic exporter and consequently is strongly involved in multidrug resistance (MDR) and drug‐drug interactions. In this work we focus on our in‐house developed SIBAR approach for prediction of ABCB1 substrates. SIBAR values were calculated on basis of three different descriptor sets: 2D‐MOE descriptors, VSA descriptors and 3D Autocorrelation vectors using in total four reference sets. In order to compare linear with non‐linear classification methods we used binary QSAR and a support vector machine (SVM), respectively. Results demonstrate that with 2D‐MOE and VSA‐descriptors prediction of non substrates performs better, whereas autocorrelation vectors show higher accuracy for substrates. With respect to the different reference sets used in this case selection on basis of maximum diversity yielded better results than a set derived from the training set compounds. In general, the models show distinct differences in their performance depending on the combination of method and descriptor type.