bluuebunny/crossref_metadata_2025 huggingface dataset:
Implementation of a continuous admission model reduces the length of stay of patients on an internal medicine clinical teaching unit
Authors: Szecket Nicolas , Wong Hannah J. , Wu Robert C. , Berman Hershl D. , Morra Dante
Published: September 2011

BACKGROUND:

Optimizing hospital operations is a critical issue facing healthcare systems. Reducing unnecessary variation in patient flow is likely to improve efficiency and optimize capacity for hospital inpatients. The objective of this study was to determine whether changing admissions, from a “bolus” system to a “drip” system, would result in a smoothed daily discharge rate, and reduce the length of stay of patients on a General Internal Medicine clinical teaching unit over a period of 1 year.

METHODS:

We conducted a retrospective analysis of the General Internal Medicine inpatient service at Toronto General Hospital for the 6‐month periods from March to August during 2 consecutive years. Length of stay distributions and daily discharge rate variations were compared between the 2 study periods.

RESULTS:

There were a total of 2734 discharges, 1446 occurring in the pre‐change period, and 1288 in the post‐change period. There was overall smoothing of the daily discharge rates, and a reduction of 0.3 days in median length of stay in the post‐change period (P = 0.0065).

CONCLUSIONS:

Restructuring the admission system to achieve constant daily admissions to each care team resulted in a smoothing of daily discharge rates and improved operational efficiency with shorter lengths of stay. Journal of Hospital Medicine 2011;. © 2011 Society of Hospital Medicine.
Median nerve deformation in differential finger motions: Ultrasonographic comparison of carpal tunnel syndrome patients and healthy controls
Authors: van Doesburg Margriet H. M. , Henderson Jacqueline , Yoshii Yuichi , van der Molen Aebele B. Mink , Cha Stephen S. , An Kai‐Nan , Amadio Peter C.
Published: September 2011

We investigated the median nerve deformation in the carpal tunnel in patients with carpal tunnel syndrome and controls during thumb, index finger, middle finger, and a four finger motion, using ultrasound. Both wrists of 29 asymptomatic volunteers and 29 patients with idiopathic carpal tunnel syndrome were evaluated by ultrasound. Cross‐sectional images during motion from full extension to flexion were recorded. Median nerve cross‐sectional area, perimeter, aspect ratio of the minimal enclosing rectangle, and circularity in extension and flexion positions were calculated. Additionally, a deformation index was calculated. We also calculated the intra‐rater reliability. In both controls and patients, the median nerve cross‐sectional area became significantly smaller from extension to flexion in all finger motions (p < 0.05). In flexion and extension, regardless of the specific finger motion, the median nerve deformation, circularity and the change in perimeter were all significantly greater in CTS patients than in controls (p < 0.05). We found excellent intra‐rater reliability for all measurements (ICC > 0.84). With this study we have shown that it is possible to assess the deformation of the median nerve in carpal tunnel syndrome with ultrasonography and that there is more deformation of the median nerve in carpal tunnel syndrome patients during active finger motion. These parameters might be useful in the evaluation of kinematics within the carpal tunnel, and in furthering our understanding of the biomechanics of carpal tunnel syndrome in the future. © 2011 Orthopaedic Research Society. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:643–648, 2012
Article alerts: items from 2010, part I
Authors: Hafdahl Adam R.
Published: September 2011

This third installment of the ‘Article Alerts’ feature section highlights 100 articles published in 2010 for the print component. More than 400 books and chapters and more than 100 dissertations and theses were added to the archive component since the last installment. Many items in the online supplemental material now include an identifier to facilitate online access. Copyright © 2011 John Wiley & Sons, Ltd.
Potent antitumour activity of the combination of HSV‐TK and endostatin armed oncolytic adeno‐associated virus for bladder cancer in vitro and in vivo
Authors: Pan Jian Gang , Zhou Xing , Zeng Ge Wa , Han Rui Fa
Published: September 2011

Background

Gene therapy may offer a new tool for the treatment of bladder cancer. Previously, we have shown a significant antitumour effect in bladder cancer xenografts in a nude mouse model using intratumoural herpes simple virus thymidine (HSV‐TK) and Endostatin gene therapy.

Objectives

Given the high vascularity of human bladder cancer and the ability of HSV‐TK or Endostatin monotherapy to eradicate the tumours, we decided to test a novel combination of cytotoxicity and antiangiogenisis gene therapy using intratumourally delivered HSV‐TK and Endostatin adeno‐associated viruses (AAVs).

Methods

We constructed plasmid AAV‐TK‐IRES‐Endostatin (pAAV‐TIE) and packaged the AAV particles contain gene fragments of HSV‐TK and Endostatin. The function of HSV‐TK and Endostatin was evaluated separately in vitro via T24 bladder tumour cells and human umbilical vein endothelial (HUVEC) cells. The combination anticancer effect of recombinant AAV‐TIE (rAAV‐TIE) was measured in vivo while rAAV‐HSV‐TK and rAAV‐Endostatin as control groups.

Results

In vitro, rAAV‐TIE was found to induce a significant increase in apoptosis in HUVEC cells equally as rAAV‐Endostatin and confirmed that the inhibition of endothelial cells mediated by rAAV‐TIE was associated with the apoptotic process. rAAV‐TIE was found to induce a significant increase in apoptosis in T24 cells equally as rAAV‐HSV‐TK and confirmed that the inhibition of T24 cells mediated by rAAV‐TIE was associated with the apoptotic process too. In vivo, our results showed that the tumours in mice injected with the rAAV‐TIE not only took significantly longer to emerge but also that their growth, once established, was significant slower than that of tumours grown, compared with single HSV‐TK or Endostatin treated animals.

Conclusions

We concluded that the inhibition of angiogenesis using Endostatin gene transfer, together with the cytotoxicity HSV‐TK gene therapy, resulted in a significant antitumour effect compared to the single gene based therapy in BTCC. The results warrant further development of the combination gene therapy, and suggest that this approach, directed towards systemic efficiency, could be used as an additional treatment for human BTCC. J. Surg. Oncol. 2012; 105:249–257. © 2011 Wiley Periodicals, Inc.
Assessment of pulpal vitality using laser speckle imaging
Authors: Stoianovici Charles , Wilder‐Smith Petra , Choi Bernard
Published: September 2011

Background and Objective

The pulpal chamber of each tooth contains the vasculature necessary to maintain a viable tooth. A critical need exists to develop an objective, repeatable method to assess pulpal viability. We hypothesized that the existence of blood perfusion within the pulp can be determined with analysis of laser speckle imaging (LSI) patterns generated by transillumination of the tooth.

Study Design/Materials and Methods

We used nine extracted human cuspids and incisors. A Tygon tube was inserted into a channel created within each tooth and Intralipid pumped through the tube in a controlled manner with a syringe infusion pump. We evaluated the feasibility of LSI for flow assessment using both transillumination and epiillumination imaging configurations. With the transillumination geometry, we also assessed the effect of the angle of incidence of the probe laser light on the speckle flow index (SFI) values extracted from the collected speckle images.

Results

Transillumination LSI, and not epiillumination LSI, enables differentiation between the absence and presence of perfusion in an in vitro tooth model. SFI values are insensitive to the relative angle of incidence of the laser light, over a wide range of angles.

Conclusions

Our preliminary in vitro data suggest that transillumination LSI is a promising method to identify the presence of blood flow in the pulpal chamber. Future in vivo evaluation is warranted. Lasers Surg. Med. © 2011 Wiley‐Liss, Inc.
Global analytic, Gevrey and C∞ hypoellipticity on the 3‐torus
Authors: Himonas A. Alexandrou , Petronilho Gerson , Carvalho dos Santos L. A.
Published: September 2011

It is proved that a class of sub‐Laplacians on the 3‐dimensional torus is globally analytic, Gevrey and C∞ hypoelliptic if and only if either a Diophantine condition holds or there is a point of finite type for the vector fields defining the operator under consideration. This work is motivated by the desire of attaining a better understanding of necessary and sufficient conditions for the global Gevrey and C∞ hypoellipticity of a sub‐Laplacian on a compact analytic manifold. This together with the more delicate local hypoellipticity are well‐known open problems in the theory of linear partial differential equations.
High frequency and reduced penetrance of lRRK2 g2019S mutation among Parkinson's disease patients in Cantabria (Spain)
Authors: Sierra María , González‐Aramburu Isabel , Sánchez‐Juan Pascual , Sánchez‐Quintana Coro , Polo José Miguel , Berciano José , Combarros Onofre , Infante Jon
Published: September 2011

The frequency and penetrance of the LRRK2 G2019S mutation varies considerably in different Parkinson disease (PD) populations. This information is essential both for clinical purposes and genetic counseling. The objective of this study was to estimate the prevalence and penetrance of the G2019S mutation of the LRRK2 gene in a small region in northern Spain (Cantabria). The G2019S mutation was tested in 367 consecutive patients with PD attended as outpatients in a tertiary Hospital in Northern Spain, and 126 at‐risk family members of probands were also investigated for G2019S mutation and disease status. The gene penetrance was estimated in terms of cumulative age‐specific incidence of PD by the Kaplan‐Meier method. Thirty‐two PD patients (8.7%) carried the G2019S mutation. Penetrance estimation of the G2019S mutation was 2% at 50 years, 12% at 60 years, 26% at 70 years, and 47% at 80 years. The frequency of the G2019S mutation of the LRRK2 gene in PD patients from Cantabria is among the highest reported so far after North African Arabs and Ashkenazi Jews. At the age of 80 years only one‐half of G2019S mutation carriers manifest motor symptoms of PD. © 2011 Movement Disorder Society
Observation and numerical simulation of an event of vortex/wave shedding from a mountain near the Hong Kong International Airport
Authors: Chan Pak Wai
Published: September 2011

In the evening of 11 April 2011, vortex/wave shedding from a mountain to the south of the Hong Kong International Airport (HKIA) appeared to occur following the establishment of fresh to strong easterly airflow in Hong Kong. This paper documents the observations by the various meteorological instruments of the event and discusses the possibility of forecasting the vortex/wave shedding using a high resolution numerical weather prediction (NWP) model. The vortex/wave shedding was well observed by the Light Detection and Ranging (LIDAR) system at HKIA. The vortex/wave appeared as an area of reversed flow against the background east to southeasterly airflow in the airport area. It was detached from the mountain and moved to the northwest with the background southeasterly flow, with a gradual decrease of the spatial extent in the area of reversed flow. The vortex/wave brought about significant wind shear to both arrival flight paths to the west of HKIA, as evidenced from the headwind profile data measured by the LIDARs and the aircraft data. It had rather large vertical extent, reaching the top of the boundary layer, but did not extend downward to the surface, as shown from the vertical scans of the LIDAR and the surface wind observations. The shedding event is successfully captured by high‐resolution NWP model with a spatial resolution of 50 m. The model output has a lead time of 6–7 h ahead of the event, indicating the possible occurrence of terrain‐induced wind shear in the form of vortex/wave shedding from a mountain. As a result, the numerical simulation could be useful in giving an early alert to the aviation weather forecaster about the significant wind shear event, which could be hazardous to the landing aircraft. Copyright © 2011 Royal Meteorological Society
Evaluation of the acute effects of distal coronary microembolization using multidetector computed tomography and magnetic resonance imaging
Authors: Saeed Maythem , Hetts Steven W. , Ursell Philip C. , Do Loi , Kolli K. Pallav , Wilson Mark W.
Published: September 2011

The purpose of this study was to test the potential of clinical imaging modalities, 64‐slice multidetector computed tomography (MDCT) and 1.5T magnetic resonance imaging (MRI) for qualitative and quantitative evaluation of acute microinfarcts and to determine the effects of <120 μm microemboli on left ventricular function, perfusion, cardiac injury biomarkers, arrhythmia, and cellular and vascular structures. Under X‐ray fluoroscopy, 40–120 μm (16 mm3) microemboli were delivered to embolize the left anterior descending (LAD) coronary artery of nine pigs. MDCT/MRI were performed at 72 h in a single session. Microinfarcts were visible in six of nine animals on delayed contrast‐enhanced MDCT/MR images but measurable in all animals using semiautomated threshold methods. Other MDCT and MRI sequences demonstrated decline in left ventricular ejection fraction, regional strain and perfusion in visible and invisible microinfarcted regions. Microemboli caused significant elevation in cardiac injury enzymes and arrhythmias. Various sizes of microinfarcts appeared microscopically as distinct aggregates of macrophages replacing myocardium. Semiautomated threshold methods are necessary to measure and confirm/deny the presence of myocardial microinfarcts. This study offers support for alternative applications of MDCT/MRI in assessing clinical cases in which microemboli <120 μm escape protective devices during percutaneous coronary interventions. Although microembolization resulted in no mortality, it caused left ventricular dysfunction, perfusion deficit, cellular damage increase in cardiac injury enzymes, and arrhythmias. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
RXR antagonism induces G0/G1 cell cycle arrest and ameliorates obesity by up‐regulating the p53–p21$^{\rm{Cip1}}$ pathway in adipocytes
Authors: Nakatsuka Atsuko , Wada Jun , Hida Kazuyuki , Hida Aya , Eguchi Jun , Teshigawara Sanae , Murakami Kazutoshi , Kanzaki Motoko , Inoue Kentaro , Terami Takahiro , Katayama Akihiro , Ogawa Daisuke , Kagechika Hiroyuki , Makino Hirofumi
Published: September 2011

The peroxisome proliferator activated receptor‐γ (PPARγ) agonist, pioglitazone (PIO), exerts anti‐diabetic properties associated with increased fat mass, whereas the retinoid X receptor (RXR) antagonist HX531 demonstrates anti‐obesity and anti‐diabetic effects with reduced body weight and fat pad mass. The cell cycle abnormality in adipocytes has not been well‐investigated in obesity or during treatment with modulators of nuclear receptors. We therefore investigated cell size and cell cycle distributions of adipocytes in vivo and examined the expression of cell cycle regulators in cultured human visceral preadipocytes. The cell size distribution and cell cycle analyses of in vivo adipocytes derived from OLETF rats demonstrated that HX531 brought about G0/G1 cell cycle arrest associated with the inhibition of cellular hypertrophy, which resulted in the reduction of fat pad mass. In contrast, PIO promoted proliferation activities associated with the increase in M + late M:G0 + G1 ratio and the appearance of both small and hypertrophied adipocytes. In cultured human visceral preadipocytes HX531 up‐regulated cell cycle regulators, p53, p21$^{\rm{Cip1}}$, cyclin D1, Fbxw7 and Skp2, which are known contributors towards G0/G1 cell cycle arrest. The knockdown of p53 with a shRNA lentivirus reversed the HX531‐induced up‐regulation of p21$^{\rm{Cip1}}$, which is one of the major p53‐effector molecules. We conclude that HX531 exerts anti‐obesity and anti‐diabetes properties by up‐regulating the p53‐p21$^{\rm{Cip1}}$ pathway, resulting in G0/G1 cell cycle arrest and the inhibition of cellular hypertrophy of adipocytes. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Properties of chlorinated polyethylene rubber/ethylene vinyl acetate copolymer blend‐based foam
Authors: Zhang Bao Sheng , Zhang Zhen Xiu , Lv Xiu Feng , Lu Bing Xue , Xin Zhen Xiang
Published: September 2011

A series of chlorinated polyethylene rubber (CM)/ethylene vinyl acetate (EVA) blends were prepared at different blending ratio. The blends were foamed by compression molding and azodicarbonamide (AZDC) was used as chemical blowing agent. Cure characteristics were researched first, and then the morphology and physical properties were investigated. It was found that neat CM foams presented a series of problems such as low hardness and high shrinkage ratio. To solve the above problems, some EVA was added into CM matrix. And the results indicated that these aforementioned defects were improved after the addition of EVA component. Tensile strength increased first and then fell, and morphology properties of CM/EVA blends were also investigated. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Quantum chemical study on the mechanism of intramolecular cyclization of 2‐benzyloxyphenyl trimethylsilyl ketone to give the benzofuran derivatives
Authors: Cai Dinglong , Wang Mian , Wang Jianyi , Duan Wengui
Published: September 2011

Quantum chemical calculations have been performed to explore the mechanism of intramolecular cyclization of 2‐benzyloxyphenyl trimethylsilyl ketone (acylsilane) to give the benzofuran derivatives stereoselectively. This reaction involves a formation of siloxycarbene intermediate and a C–H bond insertion of siloxycarbene. The comparative studies on three possible insertion of siloxycarbene show that the concerted insertion of siloxycarbene into C–H bond (pathway a), which needs overcoming an energy barrier of 45.1 kcal/mol, is the most unlikely pathway, and the stepwise insertion of siloxycarbene without spin multiplicity change (pathway c) is energetically more favorable than the stepwise insertion of siloxycarbene with spin multiplicity change (pathway b). More importantly, this work can provide an insight into the stereoselectivity in this reaction in atomic molecular level. The formation of siloxycarbene is calculated to be endergonic by 22.9 kcal/mol with an energy barrier of 30.2 kcal/mol, being the rate‐determining step of the whole process. Copyright © 2011 John Wiley & Sons, Ltd.
Poly(dicyclopentadiene)‐montmorillonite nanocomposite formation via simultaneous intergallery‐surface initiation and chain crosslinking using ROMP
Authors: Simons Ranya , Guntari Stefanie Nina , Goh Tor Kit , Qiao Greg G. , Bateman Stuart A.
Published: September 2011

Exfoliated poly(dicyclopentadiene) (pDCPD)—montmorillonite (MMT) nanocomposites were synthesized via intergallery‐surface‐initiated ring opening metathesis polymerization (ROMP). This is the first example of in situ polymerization of pDCPD from clay intergallery surfaces using ROMP. Grubbs catalyst was immobilized on the surface of MMT clay modified with vinylbenzyl dimethyloctadecyl ammonium chloride (VOAC), and DCPD polymerized from the clay surface while simultaneously crosslinking to form a thermoset nanocomposite in a one‐pot reaction. X‐ray diffraction and transmission electron microscopy analysis indicated that the resultant nanocomposites exhibited exfoliated morphologies with heterogeneous clay platelet distribution. Conventional bulk‐initiated nanocomposites containing VOAC modified MMT were also synthesized as a comparison, and these resulted in nanocomposites with intercalated morphologies. The differences between the morphologies demonstrated that growing polymer chains from the initiator sites on the intergallery surface of the clay platelets pushed the platelets apart during the polymerization of the intergallery‐surface‐initiated nanocomposites, aiding in the exfoliation process. Compression testing indicated that the intergallery‐surface‐initiated nanocomposites led to improvements of up to 50% in the compressive Young's Modulus, while the bulk‐initiated nanocomposites at the same clay loadings did not exhibit improved properties. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Unravelling the detailed microstructure of a semiconducting (quasi‐metal) soluble polymer incorporating conjugated thienylene methine sequences
Authors: Stagnaro Paola , Panizza Manuela , Gandini Alessandro , Prevosto Daniele , Lucchesi Mauro
Published: September 2011

This article reports a thorough spectroscopic characterization and the complete microstructural unravelling of a novel soluble poly(thienylene methylene) recently obtained by a straightforward process based on the methanesulfonic acid‐catalyzed self‐condensation of 2‐acetoxymethyl‐3,4‐dimethylthiophene. These macromolecules were found to generate both in situ (in the acidic reaction medium) and ex situ (by the addition of appropriate dopants) conjugated sequences consisting of alternating aromatic‐ and quinoid‐like thiophene rings, that is, conjugated thienylene methine sequences. The effect of different types of dopants on the electronic features of these polymers was assessed by the extent of bathochromic shifts they induced in the macromolecule UV–vis spectra. Doped films obtained by solution casting were characterized by dielectric spectroscopy to evaluate their electronic conductivity. The observed low values of conductivity were explained on microscopic basis evidencing the presence of polymer branching. All the structures arising from side reactions responsible for branching were determined by an exhaustive NMR study, which led to the formulation of the corresponding mechanisms. Remarkably, all these polymers, irrespective of their specific structural features and molecular weights, retained complete solubility in common solvents. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
“Smart” poly(2‐(dimethylamino)ethyl methacrylate‐ran‐9‐(4‐vinylbenzyl)‐9H‐carbazole) copolymers synthesized by nitroxide mediated radical polymerization
Authors: Lessard Benoît , Marić Milan
Published: September 2011

A series of poly(2‐(dimethylamino)ethyl methacrylate‐ran‐9‐(4‐vinylbenzyl)‐9H‐carbazole) (poly(DMAEMA‐ran‐VBK)) random copolymers, with VBK molar feed compositions fVBK,0 = 0.02–0.09, were synthesized using 10 mol % [tert‐butyl[1‐(diethoxyphosphoryl)‐2,2‐dimethylpropyl]amino] nitroxide (SG1) relative to 2‐([tert‐butyl[1‐(diethoxyphosphoryl)‐2,2‐dimethylpropyl]amino]oxy)‐2‐methylpropionic acid (BlocBuilder) at 80 °C and 90 °C. Controlled polymerizations were observed, even with fVBK,0 = 0.02, as reflected by a linear increase in number average molecular weight (Mn) versus conversion X ≤ 0.6 with final copolymers characterized by relatively narrow, monomodal molecular weight distributions (Mw/Mn ≈ 1.5). Poly(DMAEMA‐ran‐VBK) copolymers were deemed sufficiently pseudo‐“living” to reinitiate a second batch of N,N‐dimethylacrylamide (DMAA), with very few apparent dead chains, as indicated by the monomodal shift in the gel permeation chromatography chromatograms. Poly(DMAEMA‐ran‐VBK) random copolymers exhibited tuneable lower critical solution temperature (LCST), in aqueous solution, by modifying copolymer composition, solution pH and by the addition of the water‐soluble poly(DMAA) segment. 1H NMR analysis determined that, in water, the VBK units of the poly(DMAEMA‐ran‐VBK) random copolymer were segregated to the interior of the copolymer aggregate regardless of solution temperature and that poly(DMAEMA‐ran‐VBK)‐b‐poly(DMAA) block copolymers formed micelles above the LCST. In addition, the final random copolymer and block copolymer exhibited temperature dependent fluorescence due to the VBK units. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
The proteomics of cancer stem cells. Potential clinical applications for innovative research in oncology
Authors: Scatena Roberto , Bottoni Patrizia , Pontoglio Alessandro , Giardina Bruno
Published: September 2011

Cancer stem cells (CSCs) or tumour‐maintaining cells are becoming an important new reality in oncology. The intriguing molecular pathophysiology of CSCs may justify some of the obscure pathogenetic, diagnostic, prognostic, and above all, therapeutic aspects of cancer and, eventually, lead to new solutions in oncology. CSC is a cell within the tumour that possesses the capacity to self‐renew and, in doing so, gives rise to the heterogeneous lineages that comprise the tumour. The precise identification of this peculiar subpopulation of cancer cells, which has some intriguing similarities to normal stem cells, is becoming an important and urgent topic in oncology. In fact, some debated CSC markers have been already adopted by pharmacological research as targets of new and/or old anticancer drugs, showing an intriguing therapeutic index. These discussed identification markers include cell surface proteins, different activated signalling pathways, several molecules of the stem cell niche, various drug resistance mechanisms (ABCG2 and ALDH), telomerase, oncogenes and oncosuppressors (p16INK4 – Rb) and lastly, various microRNAs. In this new promising area of cancer research, proteomics, in general, and oncoproteomics, in particular, can and must play a significant role if the methodological approaches and the experimental protocols are correctly designed and interpreted.
Humoral immune responses to Plasmodium falciparum among HIV‐1‐infected Kenyan adults
Authors: Nnedu Obinna N. , O'Leary Michael P. , Mutua Daniel , Mutai Beth , Kalantari‐Dehaghi Mina , Jasinskas Al , Nakajima‐Sasaki Rie , John‐Stewart Grace , Otieno Phelgona , Liang Xiaowu , Waitumbi John , Kimani Francis , Camerini David , Felgner Philip L. , Walson Judd L. , Vigil Adam
Published: September 2011

Introduction: Humoral immune responses play a pivotal role in naturally acquired immunity to malaria. Understanding which humoral responses are impaired among individuals at higher risk for malaria may improve our understanding of malaria immune control and contribute to vaccine development.

Methods: We compared humoral responses with 483 Plasmodium falciparum antigens between adults in, Kisumu (high, year‐long malaria transmission leading to partial immunity), and adults in Kisii (low, seasonal malaria transmission). Then within each site, we compared malaria‐specific humoral responses between those at higher risk for malaria (CD4+≤500) and those at lower risk for malaria (CD4+>500). A protein microarray chip containing 483 P. falciparum antigens and 71 HIV antigens was used. Benjamini–Hochberg adjustments were made to control for multiple comparisons.

Results: Fifty‐seven antigens including CSP, MSP1, LSA1 and AMA1 were identified as significantly more reactive in Kisumu than in Kisii. Ten of these antigens had been identified as protective in an earlier study. CD4+ T‐cell count did not significantly impact humoral responses.

Conclusion: Protein microarrays are a useful method to screen multiple humoral responses simultaneously. This study provides useful clues for potential vaccine candidates. Modest decreases in CD4 counts may not significantly impact malaria‐specific humoral immunity.
The salivary proteome: Challenges and perspectives
Authors: Siqueira Walter L. , Dawes Colin
Published: September 2011

We provide a brief overview of the salivary proteome but with an emphasis on the major challenges in protein identification and quantitation. Precautions are necessary to avoid proteolysis, deglycosylation and dephosphorylation of salivary proteins by microbial and host enzymes in saliva. Many proteins are differentially expressed in secretions from different salivary glands and their proportional contributions to saliva vary with the flow rate. The total protein concentration in the secretion from any one gland varies considerably, depending on factors such as flow rate, duration of stimulation, nature of the stimulus and circadian rhythms. Many plasma proteins enter saliva via gingival crevicular fluid, of which there are increased amounts in persons with gingivitis or periodontal disease. These factors must be taken into account in the identification of potential biomarkers for different oral or systemic diseases.
Small‐Angle Neutron Scattering and Contrast Variation Measurement of the Interfacial Surface Area in PBX 9501 as a Function of Pressing Intensity
Authors: Mang Joseph T. , Hjelm Rex P.
Published: September 2011

Small‐angle neutron scattering with contrast variation was used to measure the interfacial surface area in a composite high explosive formulated with a deuterated binder. Continuing our work on the effect of varying the pressing intensity on void and binder size distribution, the effect of pressing intensity on the three interfaces (HMX‐binder, HMX‐voids and binder‐voids) of the PBX 9501 microstructure was studied. Formulation of PBX 9501 with a deuterated binder allowed the neutron scattering length density contrast to be varied and thus allowed differentiation of the three interfaces. Porod analysis was used to measure the surface area. The surface area at the interfaces of HMX and binder was found to increase with increasing pressing intensity, while the surface area between HMX and voids may have decreased slightly. No evidence was found for voids within the binder at any pressing intensity.
Protein loop closure using orientational restraints from NMR data
Authors: Tripathy Chittaranjan , Zeng Jianyang , Zhou Pei , Donald Bruce Randall
Published: September 2011

Protein loops often play important roles in biological functions. Modeling loops accurately is crucial to determining the functional specificity of a protein. Despite the recent progress in loop prediction approaches, which led to a number of algorithms over the past decade, few rigorous algorithmic approaches exist to model protein loops using global orientational restraints, such as those obtained from residual dipolar coupling (RDC) data in solution nuclear magnetic resonance (NMR) spectroscopy. In this article, we present a novel, sparse data, RDC‐based algorithm, which exploits the mathematical interplay between RDC‐derived sphero‐conics and protein kinematics, and formulates the loop structure determination problem as a system of low‐degree polynomial equations that can be solved exactly, in closed‐form. The polynomial roots, which encode the candidate conformations, are searched systematically, using provable pruning strategies that triage the vast majority of conformations, to enumerate or prune all possible loop conformations consistent with the data; therefore, completeness is ensured. Results on experimental RDC datasets for four proteins, including human ubiquitin, FF2, DinI, and GB3, demonstrate that our algorithm can compute loops with higher accuracy, a three‐ to six‐fold improvement in backbone RMSD, versus those obtained by traditional structure determination protocols on the same data. Excellent results were also obtained on synthetic RDC datasets for protein loops of length 4, 8, and 12 used in previous studies. These results suggest that our algorithm can be successfully applied to determine protein loop conformations, and hence, will be useful in high‐resolution protein backbone structure determination, including loops, from sparse NMR data. Proteins 2012. © 2011 Wiley Periodicals, Inc.
Examples of safety studies and SIL analysis on the ammonia plants of OCI Nitrogen
Authors: Duisters Harrie
Published: September 2011

A safety audit is almost invariably performed on new plant designs in the chemical industry. This will include at least a Hazop study of the basic design. Many plant owners also require an analysis of the safety integrity level or other methods of the installed safety measures.

The concept of acceptable risk changes with time, but many existing plants operate year after year without a systematic assessment of the safety level, even if the plant is revamped or modified. In addition, operating procedures may change without all safety aspects being considered in a formalized way. This sometimes leads to very dangerous and costly incidents, which could have been avoided if regular and systematic safety audits had been performed.

This article will discuss the systematic safety assessments that are performed at regular intervals on the 40‐ and 27‐years old OCI Nitrogen ammonia plants in The Netherlands. Examples are presented showing learning points that were found after a Hazop and a SIL analysis. © 2011 American Institute of Chemical Engineers Process Saf Prog, 2012
AlGaN/GaN heterojunction bipolar transistors by ammonia molecular beam epitaxy
Authors: Raman Ajay , Hurni Christophe A. , Speck James S. , Mishra Umesh K.
Published: September 2011

We demonstrate AlGaN/GaN heterojunction bipolar transistors (HBTs) by ammonia molecular beam epitaxy (NH3 MBE). The several benefits offered by NH3 MBE for the growth of GaN based vertical electronic devices are discussed. To obtain good ohmic contacts to the base layer, devices were fabricated with two different processes involving regrowths – regrown base contact (Wafer A) and regrown emitter (Wafer B). Devices on Wafers A and B had similar DC performance. Common emitter (CE) operation with a peak collector current density, JC > 1 kA/cm2 was obtained from devices on both wafers. In CE operation, a current gain (β) of 1.5–3 is observed in devices on both wafers. High base resistance is found to limit the current gain in CE operation, by limiting the base‐emitter bias voltage in the active region of the device. Maximum β values observed from Gummel plots at a fixed base‐collector (BC) bias of zero volts, are β ∼ 15 at JC = 0.88 kA/cm2 for Wafer A and β ∼13.5 at JC = 3 kA/cm2 for Wafer B. In devices on both wafers, variation is observed in the plots of β versus IC (collector current) for devices with the same emitter dimensions and geometry but with different lateral spacing between emitter mesa and base contacts (WEB). Peak β obtained is also observed to vary with WEB. An explanation is provided for the observed behaviour. This work demonstrates the potential of NH3 MBE for the growth of GaN HBTs.
GaN‐based p–i–n X‐ray detection
Authors: Yao Changsheng , Fu Kai , Wang Guo , Yu Guohao , Lu Min
Published: September 2011

GaN‐based p–i–n X‐ray detectors have been fabricated. We observed using SEM that the surface of a GaN sample has a large number of hexagonal defects. The SEM results show that GaN itself contains numerous screw dislocations that will be the flow channel of leakage current, which in turn increased the reverse‐bias leakage current of detectors. We have observed a two‐step increase in X‐ray photocurrent, which is caused by two different detection mechanisms: photovoltaic and photoconductive, and the total photocurrent (Jp) to dark current (Jd) ratio is about 27.7 times and the net photocurrent is about 2.52 µA at 110 V reverse bias. As the X‐ray accelerating voltage increases, the photocurrent has a sublinear trend.
Ultra‐fast efficient synthesis of one‐dimensional nanostructures
Authors: Dąbrowska Agnieszka , Huczko Andrzej , Soszyński Michał , Bendjemil Badis , Micciulla Federico , Sacco Immacolata , Coderoni Laura , Bellucci Stefano
Published: September 2011

Self‐propagating high‐temperature synthesis (SHS) can be regarded as an efficient method to obtain new nanomaterials. Different starting mixtures of magnesium powder with various carbonates (Li2CO3, Na2CO3, CaCO3, FeCO3, (NH4)2CO3) were tried and the auto‐thermal reactions were carried out under both reactive (air) and neutral atmosphere (argon) with an initial pressure of 1 or 10 atm to yield novel nanomaterials. Both SiC nanofibres and novel branched SiC nanostructures were also obtained from Si/polytetrafluoroethylene (PTFE) mixtures and their synthesis and purification have been optimized. The application of those one‐dimensional (1‐D) SiC nanostructures as a composite filler is presented.
Magnetoconductance of carbon nanotubes probed in parallel magnetic fields up to 60 T
Authors: Jhang Sung Ho , Margańska Magdalena , del Valle Miriam , Skourski Yurii , Grifoni Milena , Wosnitza Joachim , Strunk Christoph
Published: September 2011

Magnetoconductance of carbon nanotubes (CNTs) is investigated. We clearly show that a semiconducting CNT can be converted into a metallic one, or vice versa, with the application of a large magnetic field parallel to the tube axis, providing a consistent confirmation of the Aharonov–Bohm (AB) effect on the band structure of CNTs. We also demonstrate that magnetic‐field values where the semiconductor‐to‐metal transition occurs can be tuned by mechanical strain. Combined control of both the strain and the AB effect may open up new possibilities for CNT devices. In addition, we propose an idea to manipulate spin‐split subbands of CNTs, resulting from spin–orbit interaction (SOI), by using the magnetic field to generate sizeable spin‐polarized currents.

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Split magnetoconductance peak due to SOI.
Dual action of light in photodarkened Ge–As–S films
Authors: Arsova Darina , Vateva Elena
Published: September 2011

In annealed chalcogenide films, thinner than 1 µm, highly expressed photodarkening (PD) can be fully restored after prolonged illumination. It was supposed that this light annealing effect (LAE) results from the dual action of light, which provokes not only increase of network disorder at PD but also decrease of disorder leading to photobleaching (PB), competing with PD. To confirm it, the changes of two parameters of disorder are studied: the Tauc slope B1/2, dependent on network bonding character, and the Urbach energy Eu, associated with tailing of the band edges. It is found that B1/2 decreases during PD and increases when PB overcomes the PD, which is direct evidence that the basis of the LAE is the dual action of light. The changes of disorder defined by Eu are found to be mostly inversely related to the changes of B1/2. The peculiarities of this relationship after various treatments are presented and the problem of the correspondence of both parameters of disorder is discussed.
Ab initio investigations on ballistic transport through carbon atomic chains attached to armchair and zigzag edged graphene electrodes
Authors: Ambavale S. K. , Sharma A. C.
Published: September 2011

Ballistic transport through carbon atomic chain (CAC) attached to relaxed armchair graphene (ACG), zigzag graphene (ZZG), and unrelaxed armchair graphene (UACG) electrodes have been investigated, as a function of energy measured from Fermi level with the use of PWSCF code of Quantum Espresso package. Our computed results show that the equilibrium conductance of CAC attached to ZZG‐electrodes tends to zero over a wide energy range across Fermi level. Similar behaviour of conductance is not seen when ZZG electrodes are replaced by ACG electrodes. CAC connected to ACG electrode is found better conducting as compared to CAC connected to ZZG electrode. The computed conductance, for a fixed energy value, strongly depends on whether CAC is attached to ZZG, ACG or UACG electrodes, suggesting that transport through electrode–CAC–electrode system depends on electrode edge structure. On comparing conductance of CAC connecting to graphene electrodes with that of CAC attached to metallic (Al) electrodes, we find that replacement of metallic electrode by graphene makes conductance smoother over wider energy range.

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Indirect comparisons in the comparative efficacy and non‐inferiority settings
Authors: Snapinn Steven , Jiang Qi
Published: September 2011

International Conference on Harmonization E10 concerns non‐inferiority trials and the assessment of comparative efficacy, both of which often involve indirect comparisons. In the non‐inferiority setting, there are clinical trial results directly comparing an experimental treatment with an active control, and clinical trial results directly comparing the active control with placebo, and there is an interest in the indirect comparison of the experimental treatment with placebo. In the comparative efficacy setting, there may be separate clinical trial results comparing each of two treatments with placebo, and there is interest in an indirect comparison of the treatments. First, we show that the sample size required for a trial intended to demonstrate superiority through an indirect comparison is always greater than the sample size required for a direct comparison. In addition, by introducing the concept of preservation of effect, we show that the hypothesis addressed in the two settings is identical. Our main result concerns the logical inconsistency between a reasonable criterion for preference of an experimental treatment to a standard treatment and existing regulatory guidance for approval of the experimental treatment on the basis of an indirect comparison. Specifically, the preferred treatment will not always meet the criterion for regulatory approval. This is due to the fact that the experimental treatment bears the burden of overcoming the uncertainty in the effect of the standard treatment. We consider an alternative approval criterion that avoids this logical inconsistency. Copyright © 2011 John Wiley & Sons, Ltd.
Thin Laminate Films for Barrier Packaging Application – Influence of Down Gauging and Substrate Surface Properties on the Permeation Properties
Authors: Mueller Kajetan , Schoenweitz Claudia , Langowski Horst‐Christian
Published: September 2011

A reduction in thickness of barrier laminated film systems generally leads to a quality decrease of the resulting packaging materials' functional properties. Especially for food packaging applications, adequate oxygen and water barrier properties are indispensable. The focus of this study was therefore the development of thin film systems using metallized aluminium or ethyl vinyl alcohol barrier laminates with low oxygen and water vapour transmission properties. Biaxially oriented polyethylene terephthalate and biaxially oriented polypropylene aluminium‐coated thin film laminates as well as corresponding ethyl vinyl alcohol film systems could be successfully produced with oxygen transmission rates of <0.5 cm³(STP)/(m² d bar) and water barrier values of <0.1 g/(m² d). It could be confirmed that the film thickness of these materials within the range of the investigated dimensions does not have an influence on the barrier properties. In fact, the parameters of the production process influence the functional properties of the film systems and must therefore be adapted. Machinability of these excellent thin film systems requires further investigation on packaging lines before they can be transferred to packaging application. Copyright © 2011 John Wiley & Sons, Ltd.
An improved discrete logarithm‐based multisignature scheme
Authors: Wang Lian Jie , Chen Jonathan Jen‐Rong
Published: September 2011

Many researchers have investigated the Rivest, Shamir, and Adleman (RSA) and ElGamal algorithms for digital multisignatures. Computational and communicational costs increase rapidly after a series of signings; these methods are unsuitable for organizations with multiple geographic locations. Because these methods require many online tasks, problems such as theft, data falsification, and masquerading often occur. This study therefore proposes a digital multisignature scheme that decreases computational costs and achieves quick validation. Copyright © 2011 John Wiley & Sons, Ltd.
The impact of randomization on the analysis of clinical trials
Authors: Rosenkranz Gerd K.
Published: September 2011

The design of a comparative clinical trial involves a method of allocating treatments to patients. Usually, this assignment is performed to achieve several objectives: to minimize selection and accidental bias, to achieve balanced treatment assignment in order to maximize the power of the comparison, and most importantly, to obtain the basis for a valid statistical inference. In this paper, we are concerned exclusively with the last point. In our investigation, we will assume that measurements can be decomposed in a patient‐specific effect, a treatment effect, and a measurement error. If the patient can be considered to be randomly drawn from a population, the randomization method does not affect the analysis. In fact, under this so‐called population model, randomization would be unnecessary to obtain a valid inference. However, when individuals cannot be considered randomly selected, the patient effects may become fixed but unknown constants. In this case, randomization is necessary to obtain valid statistical analyses, and it cannot be precluded that the randomization method has an impact on the results. This paper elaborates that the impact can be substantial even for a two‐sample comparison when a standard t‐test is used for data analysis. We provide some theoretical results as well as simulations. Copyright © 2011 John Wiley & Sons, Ltd.
Integrity in student development
Authors: Roberts Dennis C. , Banta Trudy W.
Published: September 2011

After discussing the relationship between theory and practice, the authors promote assessment as a means to improve the integrity of student development.
Study on molecular mechanism for improving neural regeneration after repair of sciatic nerve defect in rat by acellular nerve allograft
Authors: Zhang Lixin , Lv Xiaoying , Tong Xiaojie , Jia Hua , Li Zhenhua
Published: September 2011

Objective: Discuss the molecular mechanism for improving neural regeneration after repair of sciatic nerve defect in rat by acellular nerve allograft (ANA). Methods: Randomly divide 36 Wistar rats into six groups as normal control group, autografting group, and bridging groups of 2, 4, 8, 12 weeks, six rats for each group. Observe the expression of brain‐derived neurotrophic factor (BDNF) in L4 spinal cord and anterior tibial muscle at the injury site, calcitonin gene‐related peptide (CGRP) protein as well as mRNA, respectively. 12w after operation, histopathological observation was performed. Results: 2w after ANA bridging the sciatic nerve defect in rats, it was observed that the expression level of BDNF in spinal cord at the injury site and CGRP protein increased, reaching the peak level at 4w, lasting till 8w, then decreased but still significantly higher than that in normal control group at 12w, and was not significantly different compared with that in autografting group. However, the expression level of BDNF in anterior tibial muscle decreased gradually within the initial 4w, then increased progressively, reaching normal level at 12w, and was not significantly different compared with that in autografting group. The expression of BDNF mRNA and CGRPmRNA was essentially the same. 12w after operation, there was nerve regeneration in bridging group of 12w and autografting group. Conclusions: ANA possessed fine histocompatibility, and might substitute autograft to repair long‐segment defect of sciatic nerve in rats. This action might be related to upregulation of protein and mRNA expression for BDNF and CGRP in spinal cord. Synapse, 2012. © 2011 Wiley Periodicals, Inc.