bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of the zeta potential for stationary phase characterization in ion chromatography
Authors: Buszewski Bogusław , Jaćkowska Magdalena , Bocian Szymon , Dziubakiewicz Ewelina
Published: November 2012

Two series of homemade stationary bonded phases for ion chromatography were investigated according to their zeta potential. One set of dendrimer anion exchanger was synthesized on the polymer support whereas the second material was prepared on the silica gel. The zeta potential data in water environment as well as buffered water solution were obtained. The influence of the length of anion‐exchanger chains, the type of the support of the modified surface, and charge distribution on these data was investigated. Additionally, the zeta potential was correlated with retention factor of inorganic ions to describe their influence on the retention mechanism in ion chromatography.
Effect of Short‐Chain Branching on the Melt Behavior of Polypropylene Under Small‐Amplitude Oscillatory Shear Conditions
Authors: Palza Humberto , Quijada Raúl , Wilhelm Manfred
Published: November 2012

The melt rheological properties of several isotactic copolymers of propylene with either 1‐hexene or 1‐octadecene, synthesized by the Me2Si[2‐Me‐Ind]2ZrCl2/MAO catalytic system, are studied under small‐amplitude oscillatory shear conditions. Our results show that the addition of short‐chain branching (C4 or C16) modifies the main melt properties. The zero‐shear‐rate viscosity is strongly decreased when the comonomers are incorporated as compared with an equivalent homopolymer of the same molar mass. These experimental findings are in agreement with previous models based on the reptation theory. The plateau modulus and the reptation relaxation time are also decreased with the presence of comonomer. An increase in the activation energy of flow is observed in the polypropylene melt when short‐chain branching are incorporated. The changes in the properties depend strongly on the size of the comonomer.
Simulating the Shape‐Memory Behavior of Amorphous Switching Domains of Poly(L‐lactide) by Molecular Dynamics
Authors: Ghobadi Ehsan , Heuchel Matthias , Kratz Karl , Lendlein Andreas
Published: November 2012

The thermally induced shape‐memory effect of polymers is typically characterized by cyclic uniaxial thermomechanical tests. Here, a molecular‐dynamics (MD) simulation approach of such a cyclic uniaxial thermomechanical test is presented for amorphous switching domains of poly(L‐lactide) (PLLA). Uniaxial deformation of the constructed PLLA models is simulated with a Parinello–Rahman scheme, as well as a pragmatic geometrical approach. We are able to describe two subsequent test cycles using the presented simulation approach. The obtained simulated shape‐memory properties in both test cycles are similar and independent of the applied deformation protocols. The simulated PLLA shows high shape fixity ratios (Rf ≥ 94%), but only a moderate shape recovery ratio is obtained (Rr ≥ 30%). Finally, the structural changes during the simulated test are characterized by analysis of the changes in the dihedral angle distributions.

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Photo‐Cured Epoxy Networks Functionalized With Fe3O4 Generated by Non‐hydrolytic Sol–Gel Process
Authors: Sangermano Marco , Allia Paolo , Tiberto Paola , Barrera Gabriele , Bondioli Federica , Florini Nicola , Messori Massimo
Published: November 2012

Magnetite nanoparticles were prepared by a non‐hydrolytic sol–gel (NHSG) process in the presence of benzyl alcohol. The obtained magnetite suspensions were mixed with an aliphatic epoxy resin and the formulations were photo‐polymerized to achieve composite materials with magnetic properties. The prepared magnetite nanoparticles and epoxy composites were fully characterized in terms of their magnetic properties.
Dibromomaleimide Derivative as an Efficient Polymer Coupling Agent for Building Topological Polymers
Authors: Cui Yi , Yan Yechao , Chen Yongming , Wang Zhaohui
Published: November 2012

The dibromomaleimide derivative, N‐(4‐bromobutyl)‐dibromomaleimide (dBMIB), is found to be a highly efficient coupling agent to dimerize thiol‐terminated hydrophilic polymers by substituent reaction. When mono‐thiol poly(ethylene oxide) (PEO45‐SH) is mixed with dBMIB in an equivalent molar feed in water, a dimer of PEO45 with a maleimide unit located at the chain center, (PEO45)2MIB, is obtained quantitatively. The dBMIB is also used to dimerize thiol‐ terminated poly(N‐(2‐acryloyloxyethyl) pyrrolidone) and poly(N,N‐dimethyl acrylamide). Moreover, the butylene bromide of (PEO45)2MIB is transferred into a butylene azide, which is allowed to react with alkynyl‐terminated polystyrene to give a A2B miktoarm star polymer via a copper‐catalyzed azide–alkyne cycloaddition coupling reaction.
On irreducible p, q‐representations of Lie algebras \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {G} (0,1)$\end{document} and \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {G} (0,0)$\end{document}
Authors: Sahai Vivek , Yadav Sarasvati
Published: November 2012

In this paper, the irreducible p, q‐representations of the Lie algebras \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {G}(0,1)$\end{document} and \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathcal {G}(0,0)$\end{document} are discussed. We prove two theorems that classify certain irreducible p, q‐representations of these Lie algebras and construct their one variable models in terms of p, q‐derivative and dilation operators. As an application, we derive a p, q‐special function identity based on one such model.
Proton and Electron Conducting Polymer Composite Films Based on SBS Triblock Copolymer
Authors: Adhikari Rameshwar , Khatiwada Shankar P. , Yadav Amar P. , Lebek Werner
Published: November 2012

Summary: Conducting polymer films were prepared by introducing ionic groups via chemical modification of one of the blocks of the polystyrene‐block‐polybutadiene‐block‐polystyrene (SBS) triblock copolymer and by adding different amount of metal salts into the modified block copolymer. The butadiene part of the copolymer was partially sulphonated to prepare the proton conducting film while the epoxidized form was used to fabricate electron conducting films with different inorganic salts. The products were characterized by Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM) and potential as well as conductivity measurements.
The Conversion of Paper Mill Sludge into Absorbent for Oil Spill Sanitation – The Life Cycle Assessment
Authors: Likon Marko , Saarela Juko
Published: November 2012

Summary: A production of a sorbent material from papermill sludge positively effects the environment instead of landfilling it and replacing an expanded polypropylene absorbent with papermill sludge sorbent for oil spill sanitations. The life cycle's assessment study shows a reduction of carbon footprint for more than 14 times and reduction of water consumption for 372 kg, based on the production of sorbent material for cleaning 1,000 kg of oil spill.A conversion of the papermill sludge into sorbent material prolongs paper products' life cycle for additional two cycles. A controlled incineration converts the used sorbent into inert meta‐kaolin product which can be further used as hydrophilic sorbent material. In this way the papermill sludge's life cycle is efficiently closed.
Nanoparticles Synthesis from Corn Cob (Xylan) and Their Potential Application as Colon‐Specific Drug Carrier
Authors: Kumar Samit , Negi Yuvraj Singh
Published: November 2012

Summary: Corn Cob based Xylan, a natural polysaccharide extracted from agro‐waste may be used as a tool to deliver drugs especially to the colon because of their timely retention in the physiological environment of stomach and small intestine and can only be degraded in colon by vast anaerobic microflora like bifidobacterium. The objective of present research study is to incorporate the drug namely 5‐aminosalicylic acid (5‐ASA) into xylan macromolecular backbone, either by surface adsorption or by intermolecular covalent bond formation so that absorption of drugs is prevented in upper gastrointestinal tract (GIT). To achieve the above objective, xylan prodrug of 5‐ASA was synthesized via activation of carboxylic acid with N,N‐carbonyldiimidazole. The structure of obtained xylan prodrug was evaluated by means FT‐IR spectroscopy. The ester carbonyl absorption band was observed at 1690 cm−1 in addition to the bands originated from 5‐ASA and xylan. The resulting prodrug and xylan itself assembled into spherical nanoparticles were analyzed by scanning electron microscopy. The prodrug of 5‐ASA was synthesized which might be active against inflammatory bowel diseases, a novel thought towards advanced drug delivery from xylan based nanoparticles will be presented.
Some Physicochemical Measurements of Chitosan/Starch Polymers in Acetic Acid‐Water Mixtures
Authors: Singh Virpal , Kumari Kamlesh
Published: November 2012

Summary: Physicochemical properties of chitosan/starch solution have been studied. Chitosan/starch solutions of different concentrations (90/10, 80/20, 70/30, 60/40, 50/50, 40/60, 30/70, 20/80, 10/90) are prepared in dilute acetic acid solution (1%, 2%, 3%, 4%). It is observed that the solution of chitosan/starch is miscible over entire range of concentration. The solution properties such as viscosity, density and refractive index are measured. The influence of concentration of solution and speed of rotation on shear stress and shear rate are also determined for polymer solution.
Existence analysis for a simplified transient energy‐transport model for semiconductors
Authors: Jüngel Ansgar , Pinnau René , Röhrig Elisa
Published: November 2012

A simplified transient energy‐transport system for semiconductors subject to mixed Dirichlet–Neumann boundary conditions is analyzed. The model is formally derived from the non‐isothermal hydrodynamic equations in a particular vanishing momentum relaxation limit. It consists of a drift‐diffusion‐type equation for the electron density, involving temperature gradients, a nonlinear heat equation for the electron temperature, and the Poisson equation for the electric potential. The global‐in‐time existence of bounded weak solutions is proved. The proof is based on the Stampacchia truncation method and a careful use of the temperature equation. Under some regularity assumptions on the gradients of the variables, the uniqueness of solutions is shown. Finally, numerical simulations for a ballistic diode in one space dimension illustrate the behavior of the solutions. Copyright © 2012 John Wiley & Sons, Ltd.
Off‐resonance‐robust velocity‐selective magnetization preparation for non‐contrast‐enhanced peripheral MR angiography
Authors: Shin Taehoon , Hu Bob S. , Nishimura Dwight G.
Published: November 2012

Purpose

To develop a new velocity‐selective (VS) excitation pulse sequence which is robust to field inhomogeneity, and demonstrate its application to non‐contrast‐enhanced peripheral MR angiography (MRA).

Methods

The off‐resonance‐robust VS saturation pulse is designed by incorporating 180° refocusing pulses into the k‐space‐based reference design and tailoring sequence parameters in a velocity region of interest. The VS saturation pulse is used as magnetization preparation for non‐contrast‐enhanced peripheral MRA to suppress background tissues but not arterial blood based on their velocities. Non‐contrast‐enhanced peripheral MRA using the proposed VS preparation was tested in healthy volunteers and a patient with arterial stenosis.

Results

Calf angiograms obtained using the new VS preparation show more uniform background suppression than the reference VS preparation, as demonstrated by larger mean values and smaller standard deviations of artery‐to‐vein and artery‐to‐muscle contrast‐to‐noise ratios (71.0 ± 11.4 and 75.3 ± 12.1 versus 61.7 ± 22.7 and 58.5 ± 27.8). Two‐station peripheral MRA using the new VS preparation identifies stenosis of the femoral and popliteal arteries in the patient, as validated by digital subtraction angiography.

Conclusion

Non‐contrast‐enhanced MRA using the new VS magnetization preparation can reliably provide high angiographic contrast in the lower extremities with significantly improved immunity to field inhomogeneity. Magn Reson Med 70:1229–1240, 2013. © 2012 Wiley Periodicals, Inc.
Long‐term bladder drainage: Suprapubic catheter versus other methods: A scoping review
Authors: Hunter Kathleen F. , Bharmal Aamir , Moore Katherine N.
Published: November 2012

Aims

The purpose of this scoping review was to examine research activity comparing suprapubic catheterization to any other method of chronic bladder emptying such as intermittent and indwelling catheterization in adults in relation to complications, patient satisfaction, and health‐related quality of life (QoL).

Methods

A search of electronic databases (MEDLINE, CINAHL, SCOPUS, and OVID) was performed 1950–May 2012 using the search terms, singly or combined: suprapubic, catheter, long term, effectiveness, urinary, health promotion, incontinence, retention, QoL, and evidence based. All research designs were included. Papers were excluded if catheter duration was <30 days or were single case reports.

Results

Twenty‐six articles were identified for potential inclusion from an initial 394 and 14 retained after final review. Studies varied in subjects, outcome measures, and publication dates. The majority were retrospective reviews; four were descriptive/qualitative studies. Based on the clinical findings, suprapubic catheters are associated with a low incidence of urethral injury and stricture, but have similar rates of upper tract damage, vesicoureteral reflux, renal or bladder calculi, and symptomatic urinary tract infections compared to urethral catheters. Users report being generally satisfied with suprapubic catheters. No studies addressed stoma or skin care, urethral leakage, or adherence to the suprapubic catheter after insertion.

Conclusion

Most studies focused on clinical urologic issues rather than patient understanding of suprapubic catheter management, satisfaction, stoma and skin care, or health related QoL. Further studies are needed to elucidate efficacy from an individual user and clinician perspective. Neurourol. Urodynam. 32: 944–951, 2013. © 2012 Wiley Periodicals, Inc.
Recycled carbon fiber reinforced poly(butylene terephthalate) thermoplastic composites: fabrication, crystallization behaviors and performance evaluation
Authors: Chen Yong , Wang Xiaodong , Wu Dezhen
Published: November 2012

The thermoplastic composites based on poly(butylene terephthalate) (PBT) and recycled carbon fiber (RCF) were prepared through simple melt compounding by a twin‐screw extruder. An effective approach was utilized to clean and treat the RCF surface with a concentrated solution of nitric acid and then a solution of diglycidyl ether of bisphenol A as macromolecular coupling agent so as to improve the interfacial adhesion between the RCF and PBT matrix. As a result, the reinforcing potential of the RCF was enhanced substantially, and the mechanical properties, heat distortion temperature, and thermal stability of PBT could be significantly improved by incorporating this surface‐treated RCF. The morphologies of fracture surfaces indicated that the RCF achieved a homogeneous dispersion in the PBT matrix due to a good interfacial interaction between fiber and PBT. The investigations on the crystallization behaviors and kinetics demonstrated that the RCF acted as a nucleation agent for the crystallization of PBT, and the crystallization rate and nucleation density of PBT were increased remarkably due to the heterogeneous nucleating effect of RCF in the matrix. These features may be advantageous for the enhancement of mechanical properties, heat resistance, and processability of PBT‐based composites. This study may provide a design guide for carbon fiber‐reinforced PBT composites with a great potential as well as a low cost for industrial and civil applications. Copyright © 2012 John Wiley & Sons, Ltd.
Active proteases in nephrotic plasma lead to a podocin‐dependent phosphorylation of VASP in podocytes via protease activated receptor‐1
Authors: Harris Jessica J , McCarthy Hugh J , Ni Lan , Wherlock Matthew , Kang HeeGyung , Wetzels Jack F , Welsh Gavin I , Saleem Moin A
Published: November 2012

Focal segmental glomerulosclerosis (FSGS) is associated with glomerular podocyte injury. Podocytes undergo dramatic changes in their actin structure, with little mechanistic insight to date into the human disease. Post‐transplantation recurrence of FSGS is the archetypal form of the disease caused by unknown circulating plasma ‘factors’. There is increasing indication that plasma protease activity could be central to this disease. Using clinical plasma exchange material, collected from patients in relapse and remission stages of disease, the effects of FSGS plasma on human conditionally immortalized podocytes (ciPods) were studied. We show that vasodilator stimulated phosphoprotein (VASP) is phosphorylated in response to relapse plasma from ten consecutively tested patients, and not in response to paired remission plasma or non‐FSGS controls. The phosphorylation signal is absent in human podocytes carrying a pathological podocin mutation. To test for a plasma ligand, inhibition of proteases in relapse plasma leads to the loss of VASP phosphorylation. By the use of siRNA technology, we show that proteases in the plasma signal predominantly via protease activated receptor‐1 (PAR1) to VASP. Mechanistically, FSGS plasma increases podocyte motility, which is dependent on VASP phosphorylation. These data suggest a specific biomarker for disease activity, as well as revealing a novel and highly specific receptor‐mediated signalling pathway to the actin cytoskeleton. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Prophylactic penicillin after 5 years of age in patients with sickle cell disease: A survey of sickle cell disease experts
Authors: McCavit Timothy L. , Gilbert Megan , Buchanan George R.
Published: November 2012

Background

Since the publication of the Prophlyactic Penicillin Study II in 1995, the management of penicillin prophylaxis for children with sickle cell disease (SCD) after 5 years of age has been controversial. In this study, we sought to describe current practice patterns of pediatric hematologists related to cessation of penicillin prophylaxis for children with SCD after 5 years of age.

Procedure

We performed a cross‐sectional, electronic survey of pediatric hematologists with expertise in SCD to examine practices regarding penicillin prophylaxis in children with SCD after 5 years of age. We also investigated factors potentially associated with continuation of penicillin prophylaxis using the Jonckheere–Terpstra test and Fisher's exact test.

Results

Of the 106 physicians surveyed from 76 centers, 84% completed the survey. Among respondents, 76% routinely recommended cessation of penicillin prophylaxis after 5 years of age. The practice of routinely continuing penicillin after 5 years of age was associated with decreased concern about antibiotic resistance in Streptococcus pneumoniae (P = 0.01), with the usage of prophylactic penicillin in mild SCD genotypes (sickle hemoglobin‐C disease and sickle β+ thalassemia, P = <0.001), and with increasing use of other preventive evaluations (e.g., MRI for silent stroke) in childhood (P = 0.05).

Conclusion

Most pediatric hematologists with an SCD expertise recommend cessation of prophylactic penicillin after 5 years of age. Pediatr Blood Cancer 2013; 60: 935–939. © 2012 Wiley Periodicals, Inc.
Pulmonary hypertension following haematopoietic stem cell transplantation for primary haemophagocytic lymphohistiocytosis
Authors: Zeilhofer Ulrike , Ashworth Michael , Amrolia Persis , Rao Anupama , Chiesa Robert , Veys Paul , Rao Kanchan
Published: November 2012

We report two children who developed severe, fatal pulmonary hypertension (PHT) after mismatched unrelated donor cord blood transplantation using reduced intensity conditioning for HLH. PHT was diagnosed on post mortem lung biopsies with no evidence of HLH, pulmonary veno‐occlusive disease, infection or of idiopathic pulmonary hypertension. PHT may be an association with HLH and physicians treating HLH should be aware of this potential association. Pediatr Blood Cancer 2013; 60: 521–523. © 2012 Wiley Periodicals, Inc.
Clinical and hematological features of homozygous hemoglobin O‐Arab [beta 121 Glu → Lys]
Authors: Dror Sayar
Published: November 2012

Hemoglobin O‐Arab [Beta 121 Glu → Lys] (Hb O‐Arab) is a rare abnormal hemoglobin (Hb) whose clinical and hematological features have been described in adults but not in children. We report three children, 9, 12, and 36 months of age, with homozygous Hb O‐Arab and assess the value of supplementary folic acid as treatment. Pediatr Blood Cancer 2013; 60: 506–507. © 2012 Wiley Periodicals, Inc.
Minimization of surface friction effect on scratch‐induced deformation in polymers
Authors: Hossain Mohammad Motaher , Minkwitz Rolf , Sue Hung‐Jue
Published: November 2012

Surface friction plays an important role in influencing the stress field development during scratch process, thus, scratch‐induced deformation mechanisms. In this study, three‐dimensional finite element method (FEM) parametric study was performed along with experimental validation to investigate the effect of surface friction on scratch‐induced deformation and its correlation with the constitutive behavior of polymers. As scratch depth and shoulder height are the key parameters for causing scratch visibility, the focus is to investigate the effect of surface friction on these two scratch‐induced deformation features and how the surface friction effect can be altered by varying the constitutive parameters. The FEM findings and experimental observations indicate that onset of groove formation during the scratch process is strongly influenced by yield stress and coefficient of surface friction. Also, the relative frictional effect on scratch‐induced deformation becomes minimal if the post‐yielding strain hardening slope of the polymer is high. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Maize proteomics: An insight into the biology of an important cereal crop
Authors: Pechanova Olga , Takáč Tomáš , Šamaj Jozef , Pechan Tibor
Published: November 2012

Maize (Zea mays L.) is the most grown cereal crop in the world (839 million tons in 2012). According to its agro‐economical importance, maize has received tremendous attention from research communities of academic, state, and industry origin. In this manuscript, we aspire to provide readers with the first comprehensive review of proteomics studies performed on maize within a 1987–2012 time period. The following topics are presented here: maize proteome profiling, developmental proteomics, response to abiotic and biotic stress, maize phosphoproteomics, tissue‐specific wild‐type versus mutant analyses, heterosis, seed viability, maize allergens, and safety assessment of genetically modified maize. Tissues, organelles, subcellular compartments, secretomes, methods, phenomena, and pertinent proteins were summarized and referenced in tables and figures to provide readers with expediently accessible information in the context of up‐to‐date achievements. This review illustrates maize proteomics as a firmly established research area with laboratories around the world diligently advancing our knowledge of diverse aspects of maize biology.
Screening for depression with Centre for Epidemiological Studies Depression Scale Revised and its implication for consultation–liaison psychiatry practice among cancer subjects: a perspective from a developing country
Authors: Olagunju Andrew T. , Aina Olatunji F. , Fadipe Babatunde
Published: November 2012

Objective

Co‐morbidity of depressive symptomatology is a common indication for use of mental health services in oncology. In this regard, screening instruments are useful for prompt identification of mental disorders in cancer. This study is set to evaluate the diagnostic validity of Centre for Epidemiological Studies Depression Scale Revised (CES‐DR) for depression screening in cancer.

Methods

The CES‐DR and the Schedule for Clinical Assessment in Neuropsychiatry (SCAN) were administered by the researchers on 200 attendees of a Nigerian hospital with histological diagnoses of cancer. Subsequently, the diagnostic validity of CES‐DR was compared with SCAN.

Results

Ninety‐eight (49.0%) participants had significant depressive symptomatology (CES‐DR scores of ≥16) as against the diagnosis of depression in 55 (27.5%) participants following SCAN interview. Furthermore, of these 55 (27.5%) depressed participants, two (3.6%) participants had CES‐DR scores <16 (non‐cases). The Cronbach's alpha reliability of CES‐DR was 0.86, and sensitivity and specificity of CES‐DR were 96.4% and 68.7%, respectively, whereas positive and negative predictive values of CES‐DR were found to be 0.54 and 0.98, respectively, in this study. The average administration time of CES‐DR was 6 (±2) min, and an inter‐rater reliability of 93.7% was observed.

Conclusions

The CES‐DR was found in this study to be a useful tool for screening for depression in cancer but with diagnostic limitation when compared with SCAN. The development as well as popularization of screening instrument(s) with improved diagnostic and administration property for prompt identification of mental disorders to improve consultation–liaison psychiatry services in cancer care is recommended. Furthermore, replication of similar research is warranted. Copyright © 2012 John Wiley & Sons, Ltd.
Cardiac fibroma, anomalous pulmonary venous course, and persistent pneumonia in a patient with gorlin syndrome
Authors: Kopp Benjamin T. , Rosen Kerry L. , O'Donovan Julie C. , Sheikh Shahid
Published: November 2012

We report the unusual case of a child referred for persistent pneumonia and possible pulmonary nodules who was found to have a cardiac fibroma and diagnosed with Gorlin syndrome. Pulmonologists should be aware of the potential for vascular anomalies associated with this syndrome as well as the risk for pulmonary metastases from primary skin tumors. Pediatr Pulmonol. 2014; 49:E7–E9. © 2013 Wiley Periodicals, Inc.
Left main bronchus compression as a result of tuberculous lymphnode compression of the right‐sided airways with right lung volume loss in children
Authors: Andronikou S. , Van Wyk M.J. , Goussard P. , Gie R.P.
Published: November 2012

Rationale

The superior mediastinal space is confined by the sterno‐manubrium anteriorly and the vertebral column posterior. An abnormal relationship between the superior mediastinal structures may result in compression of the left main bronchus. In patients with right‐sided pneumonectomy an exaggerated compensatory response may lead to stretching and compression of the remainder of the intra‐thoracic airway. Lymphobronchial TB mimics pneumonectomy when it causes compression of the bronchus intermedius, between nodal lymphnode groups with resultant volume loss in the right lung and displacement of the mediastinum to the right. The left main bronchus may be at risk of compression due to rotation and displacement of the major vessels.

Aim

To report pediatric cases of right‐sided lymphobronchial TB with volume loss, demonstrate the use of angle measurements to quantify mediastinal dynamics and support a pathogenetic theory for left main bronchus compression.

Materials and Methods

CT scans in children with TB and right lung volume loss, were compared retrospectively with controls using angle measurements based on descriptions of the aorta‐carinal syndrome and the post‐pneumonectomy syndrome. The Mann–Whitney U‐test was used to compare groups.

Results

The “Pulmonary bifurcation angle” between the main pulmonary arteries reached statistical significance (P = 0.025). The “Pulmonary outflow tract rotation” angle (pulmonary trunk with the mid sagittal plane) approached statistical significance (P = 0.078). The left main bronchus ranged from complete obliteration in two patients to 0.7 cm. In 16 of 30 patients the size was reduced to less than 75% of expected.

Conclusion

In children with right lung volume loss from TB, the compression of the contralateral bronchus is due to narrowing of the pulmonary artery bifurcation angle as the main trunk rotates towards the midline. This is comparable to the post‐pneumonectomy syndrome. Pediatr Pulmonol. 2014; 49:263–268. © 2012 Wiley Periodicals, Inc.
Resveratrol worsens survival in SCID mice with prostate cancer xenografts in a cell‐line specific manner, through paradoxical effects on oncogenic pathways
Authors: Klink Joseph C. , Tewari Alok K. , Masko Elizabeth M. , Antonelli Jodi , Febbo Phillip G. , Cohen Pinchas , Dewhirst Mark W. , Pizzo Salvatore V. , Freedland Stephen J.
Published: November 2012

BACKGROUND

Resveratrol increases lifespan and decreases the risk of many cancers. We hypothesized resveratrol will slow the growth of human prostate cancer xenografts.

METHODS

SCID mice were fed Western diet (40% fat, 44% carbohydrate, 16% protein by kcal). One week later, human prostate cancer cells, either LAPC‐4 (151 mice) or LNCaP (94 mice) were injected subcutaneously. Three weeks after injection, LAPC‐4 mice were randomized to Western diet (control group), Western diet plus resveratrol 50 mg/kg/day, or Western diet plus resveratrol 100 mg/kg/day. The LNCaP mice were randomized to Western diet or Western diet plus resveratrol 50 mg/kg/day. Mice were sacrificed when tumors reached 1,000 mm3. Survival differences among groups were assessed using Cox proportional hazards. Serum insulin and IGF axis were assessed using ELISAs. Gene expression was analyzed using Affymetrix gene arrays.

RESULTS

Compared to control in the LAPC‐4 study, resveratrol was associated with decreased survival (50 mg/kg/day—HR 1.53, P = 0.04; 100 mg/kg/day—HR 1.22, P = 0.32). In the LNCaP study, resveratrol did not change survival (HR 0.77, P = 0.22). In combined analysis of both resveratrol 50 mg/kg/day groups, IGF‐1 was decreased (P = 0.05) and IGFBP‐2 was increased (P = 0.01). Resveratrol induced different patterns of gene expression changes in each xenograft model, with upregulation of oncogenic pathways E2F3 and beta‐catenin in LAPC‐4 tumors.

CONCLUSION

Resveratrol was associated with significantly worse survival with LAPC‐4 tumors, but unchanged survival with LNCaP. Based on these preliminary data that resveratrol may be harmful, caution should be advised in using resveratrol for patients until further studies can be conducted. Prostate 73: 754–762, 2013. © 2012 Wiley Periodicals, Inc.
A thermal theory for flammability diagrams guiding purge and inertion of a flammable mixture
Authors: Ma Tingguang
Published: November 2012

Recently, a thermal method was proposed to recheck the concept of flammability by manipulating the competition between heating and quenching. This method is further explored here to reconstruct flammability diagrams, explaining the contribution of each component toward flammability change for a mixture. Based on the assumption that a diluent will not change the flame temperature at the flammability limits, these isothermal processes lead to a conservative estimation of the flammable zone. Although rough near the inertion point, the theoretical flammability envelop has the potential to guide future purging and diluting operations. It will be a powerful tool for both educational purposes and practical utilities. © 2012 American Institute of Chemical Engineers Process Saf Prog 32: 42–48, 2013
Comparison of multiple steam treatment durations for control of bed bugs (Cimex lectularius L.)
Authors: Puckett Robert T , McDonald Danny L , Gold Roger E
Published: November 2012

Background

The factors contributing to the current resurgence of bed bug Cimex lectularius L. populations across the United States and elsewhere include, among others, the development of resistance to chemical insecticides and population management practices. This has led to the development and attempted refinement of many non‐chemical control methods that contribute to an IPM approach to solving the current bed bug population density increase in urban dwellings. One such approach is the use of heat in the form of steam to provide an effective mechanism for controlling localized infestations of bed bugs.

Results

The work reported herein was designed to refine our understanding of the duration of bed bug/steam contact necessary to affect mortality of bed bugs in laboratory trials. Beg bug eggs, nymphs and adults were exposed to three steam treatment exposure periods in these trials. Mean percentage mortality of bed bug eggs was 100% (regardless of duration of exposure), and that of nymphs and adults ranged from 88.0 to 94.0%. Survivorship of nymphs and adults in the trials was the result of experimental protocol restrictions that would not usually be associated with actual pest management efforts.

Conclusions

The treatment equipment used in these trials is portable and relatively inexpensive and represents a non‐chemical means of killing all life stages of bed bugs. While this method would likely be seen as an inefficient means of remediating a mature bed bug infestation within a structure, it does represent a practical component of integrated management of this pest insect. © 2012 Society of Chemical Industry
Osteoporosis: recommended diagnosis and management
Authors: Ralston Stuart
Published: November 2012

Osteoporosis is common in the elderly and postmenopausal women and is associated with an increased risk of low‐trauma fractures. Our Drug review outlines the recommended investigations and available treatment options, followed by sources of further information and a review of the prescription data.
Spinodal decomposition and the luminescence of Er in AlxIn1−xN:Er layers
Authors: Yang Miao , Weng Ye , Strunk Horst P.
Published: November 2012

Integrated photoluminescence intensities of the green lines from Er centers (2H11/2–4I15/2 and 4S3/2–4I15/2) embedded in AlxIn1−xN films are investigated in dependence of excitation energy and band gap energy of the film host. The films are deposited onto silicon and sapphire substrates by sputtering and subsequently annealed for optimization of the luminescence intensity. Two significant maxima of integrated intensity are observed. The first maximum appears, if the excitation energy matches the band gap energy of the AlxIn1−xN matrix. It can be explained by a bound exciton mediated energy transfer to Er centers. The second maximum occurs at below band gap energy excitation of some films with special compositions. These observations call for an adequate path for the excitation of Er. We propose a mechanism based on spinodal decomposition of AlxIn1−xN. In fact, our calculations and experiments (structure analysis in a transmission electron microscope) confirm that nanoparticles form of an In‐rich AlxIn1−xN phase, which can be assumed as quantum dots. Resonant energy transfer from these quantum dots into the luminescent centers can explain the Er luminescence enhancement.
Anisotropy of porous silicon formation rate in p‐Si
Authors: Astrova E. V. , Zharova Yu. A. , Ulin V. P. , Enicheva G. V.
Published: November 2012

We studied the anisotropy of meso‐ and microporous silicon formation rate on curved surfaces and on flat samples. Experiments on anodization of model p++‐cylinders demonstrated that faceting appears on their lateral surface. This indicates that the etching rates vary between different crystallographic planes. Quantitative data on the etching‐rate anisotropy were obtained by anodization of wafers through a mask in the form of narrow wedges radiating from a center in all directions (wagon wheel mask). We examined the dependence of porous silicon formation rate anisotropy on current and Si doping. It was shown that for p++ substrates, in all anodization modes, the <100> direction corresponds to the maximum growth rate. The current affects the etching‐rate distribution among crystallographic directions: under low currents anisotropy of pore‐front propagation rate may be as high as 20%. An even stronger influence on the anisotropy characteristics is exerted by the substrate doping level. It was found for the first time that, for silicon with acceptor concentration NB ≈ 1017–1018 cm−3, the <111> axis becomes the fastest growth direction, and the <100> axis, by contrast, is transformed to the direction of the slowest pore‐front propagation. This phenomenon correlates with rotation of the optical axis in birefringent mesoporous silicon on passing from p++‐Si to p+‐Si, as is known from the literature.
Surface passivation for ultrathin Al2O3 layers grown at low temperature by thermal atomic layer deposition
Authors: Frascaroli J. , Seguini G. , Cianci E. , Saynova D. , van Roosmalen J. , Perego M.
Published: November 2012

Thin layers of Al2O3 with thickness tox ≤ 8 nm were grown by thermal atomic layer deposition at low temperature of 100 °C and applied to achieve functional surface passivation of crystalline silicon substrates. Measurements of the effective lifetime were performed to characterize the surface passivation effect. Lifetime values in the range of 0.5 ms were obtained for Al2O3 films with tox ≥ 6 nm upon post‐deposition annealing (PDA) at 250 °C in N2 atmosphere. However, when the thickness of the Al2O3 films was reduced to 4 nm, lifetime values well below 0.1 ms were observed even after PDA. Combined capacitance–voltage and conductance–voltage measurements were carried out to extract the amount of charges located near the silicon‐oxide interface and the density of electrically active interface states, respectively. The results of the electrical characterization were used to elucidate the intimate physical mechanisms that govern charge recombination at the Al2O3/Si interface.

Density of interface states (a) and lifetime (b) values are reported as a function of the PDA temperature for Al2O3 films of three different thickness values: 4, 6, and 8 nm.

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Crystalline graphite oxide/PVDF nanocomposite gate dielectric: Low‐voltage and high field effect mobility thin‐film transistor
Authors: Sannigrahi J. , Bhadra D. , Chaudhuri B. K.
Published: November 2012

We fabricated an anthracene thin‐film transistor (TFT) with an ultrathin layer (∼450 nm) of poly‐vinylidene fluoride (PVDF)/graphite oxide nanoplatelets (GOnP) nanocomposite as a gate insulator. We obtained a TFT device with excellent electrical characteristics at low operating voltages (<1 V). The dielectric is a high‐ε gate insulator with a static dielectric constant of εr = 15.6. This device was found to have a field effect mobility of 1.1 cm2 V−1 s, a threshold voltage of 0.34 V, an exceptionally low subthreshold slope (SS) of 380 mV decade−1 and an on/off ratio of 105. The combination of favorable properties opens up the possibility to utilize such TFTs effectively at voltages as low as below 1 V. Such high‐ε PVDF/GOnP gate dielectric appears to be highly promising candidates for organic nonvolatile memories and sensor field effect transistors (FETs).
Elastic anisotropy and thermodynamic properties of tetrahedrally bonded dense C2N2(NH) under high pressure and high temperature
Authors: Yan Haiyan , Zhang Meiguang , Wei Qun , Guo Ping
Published: November 2012

The elastic anisotropy and thermodynamic properties of the potential superhard carbon nitride phase C2N2(NH) have been investigated by using an ab initio plane‐wave pseudopotential density theory method. The crystal parameters have been calculated at ambient as well as high pressure. The Young's modulus and shear modulus as a function of crystal orientations for C2N2(NH) have been systematically investigated. The Young's modulus is found to reach a maximum along the [100] direction. Using a set of total energy versus volume obtained with the first‐principles calculations, the quasiharmonic Debye model is applied to the study of the thermal and vibrational effects. The dependence of Debye temperature, Grüneisen parameter, heat capacity, and expansion coefficient on the temperature and pressure are systematically explored in the whole pressure range from 0 to 60 GPa and temperature range from 0 to 2000 K.
Neural network potentials for metals and oxides – First applications to copper clusters at zinc oxide
Authors: Artrith Nongnuch , Hiller Björn , Behler Jörg
Published: November 2012

The development of reliable interatomic potentials for large‐scale molecular dynamics (MD) simulations of chemical processes at surfaces and interfaces is a formidable challenge because a wide range of atomic environments and very different types of bonding can be present. In recent years interatomic potentials based on artificial neural networks (NNs) have emerged offering an unbiased approach to the construction of potential energy surfaces (PESs) for systems that are difficult to describe by conventional potentials. Here, we review the basic properties of NN potentials and describe their construction for materials like metals and oxides. The accuracy and efficiency are demonstrated using copper and zinc oxide as benchmark systems. First results for a potential of the combined ternary CuZnO system aiming at the description of oxide‐supported copper clusters are reported.

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Model of a copper cluster at the ZnO($10\overline {1} 0$) surface.
Raman‐scattering probe of anharmonic effects due to temperature and composition in InGaN
Authors: Kong J. F. , Shen W. Z. , Guo Q. X.
Published: November 2012

We have carried out a detailed investigation of temperature‐dependent micro‐Raman scattering on In1 − xGaxN films with different Ga compositions (0.06 ≤ χ ≤ 0.91). The observed phonon frequency downshift and linewidth broadening with increasing temperature of A1(LO) and E2(high) modes can be well explained by a model taking into account the contributions of the thermal expansion, the lattice‐mismatch‐induced strain, and the anharmonic phonon processes. We have elucidated the variation with Ga composition of the contribution of the three‐ and four‐phonon processes in the anharmonic effect. It is found that with increasing Ga composition the three‐phonon process increases over the four‐phonon process. The variation in the relative contribution from three‐ and four‐processes can be further attributed to the diversification of structural properties and phonon density of states in InGaN.
Dislocations in 4H‐ and 3C‐SiC single crystals in the brittle regime
Authors: Demenet Jean‐Luc , Amer Madyan , Tromas Christophe , Eyidi Dominique , Rabier Jacques
Published: November 2012

Nanoindentations at room temperature have been performed on 4H‐ and 3C‐SiC single crystals, and resulting microstructures have been analyzed by Transmission Electron Microscopy. In both structures, dislocations emitted from imprints are perfect dislocations lying in the basal plane for 4H‐ and in the {111} planes for 3C‐SiC. Dislocation segments are not dissociated and they are assumed to be lying in the shuffle set where only one bound per atom has to be cut for dislocation motion. It is deduced that the low stacking fault energy of silicon carbide is not involved in plasticity under high stress as compared to high temperature behaviour. The change in deformation mechanism reported in this study indicates that silicon carbide exhibits the same behaviour under high stress as other semiconducting materials, as silicon or antimonide indium. This could be a general feature for all this family of materials (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modification of dislocation PL centres due to misfit of bonded Si wafers
Authors: Steinman E. , Tereshchenko A. , Kononchuk O. , Vdovin V.
Published: November 2012

Structure and low temperature photoluminescence of Si(001) hydrophilic bonded wafers have been studied. Even at minimal misfit angles the observed dislocation related luminescence (DL) did not coincide with the luminescence of isolated dislocations. The dependence of spectral distribution of DL on the dislocation network density has been studied and analyzed on the basic of previously suggested recombination model. A strong dependence of the spectral distribution of DL on the misfit angle has been found. The temperature dependence of different sub bands in DL spectra has been interpreted in the model of successive thermal emptying of upper states. The similar behavior of DL at increasing temperature and increasing density of misfit dislocations has been interpreted in the model of a relative dependence of dislocation related upper states on the distance between dislocations (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energetic spectra of dislocation networks produced by hydrophilic bonding of silicon wafers
Authors: Kolevatov I. , Trushin M. , Vyvenko O. , Kittler M. , Kononchuk O.
Published: November 2012

Electronic states of dislocation networks produced by Si wafers bonding was studied by means of deep level transient and admittance spectroscopy methods. A strong field‐enhanced hole thermoemission was established for one shallow and one deep states in p‐type Si that was explained in the framework of dislocation‐related Poole‐Frenkel‐effect model. The shallow dislocation related states situated close to the valence as well as to the conduction band of silicon were found to be associated with the broad energetic bands with rapid interstate exchange. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of Corilagin on Membrane Permeability of Escherichia coli, Staphylococcus aureus and Candida albicans
Authors: Li Na , Luo Meng , Fu Yu‐jie , Zu Yuan‐gang , Wang Wei , Zhang Lin , Yao Li‐ping , Zhao Chun‐jian , Sun Yu
Published: November 2012

Corilagin is a member of polyphenolic tannins. Its antimicrobial activity and action mechanism against Escherichia coli, Staphylococcus aureus and Candida albicans were investigated through membrane permeability. Crystal violet staining determination, outer membrane (OM) and inner membrane (IM) permeability, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) and atomic force microscopy (AFM) were used as methods for our investigation. The minimum inhibitory concentrations were 62.5, 31.25 and 62.5 µg/mL for E. coli, S. aureus and C. albicans, respectively. Crystal violet results and SDS‐PAGE of supernatant proteins showed that corilagin dose‐dependently affected membrane permeability of E. coli and C. albicans but not of S. aureus. OM and IM permeability assays revealed comparable results for E. coli. By using AFM, we demonstrated extensive cell surface alterations of corilagin‐treated E. coli and C. albicans. SDS‐PAGE of precipitated proteins revealed possible targets of corilagin, i.e. Fib, Sae R, Sar S in S. aureus and Tye 7p in C. albicans. In conclusion, corilagin inhibited the growth of E. coli and C. albicans by disrupting their membrane permeability and that of S. aureus by acting on Fib, Sae R and Sar S but not on membrane integrity. Copyright © 2012 John Wiley & Sons, Ltd.