bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence-Based Systematic Review: Effects of Different Service Delivery Models on Communication Outcomes for Elementary School–Age Children
Authors: Cirrin Frank M. , Schooling Tracy L. , Nelson Nickola W. , Diehl Sylvia F. , Flynn Perry F. , Staskowski Maureen , Torrey T. Zoann , Adamczyk Deborah F.
Published: July 2010

Purpose

The purpose of this investigation was to conduct an evidence-based systematic review (EBSR) of peer-reviewed articles from the last 30 years about the effect of different service delivery models on speech-language intervention outcomes for elementary school–age students.

Method

A computer search of electronic databases was conducted to identify studies that addressed any of 16 research questions. Structured review procedures were used to select and evaluate data-based studies that used experimental designs of the following types: randomized clinical trial, nonrandomized comparison study, and single-subject design study.

Results

The EBSR revealed a total of 5 studies that met the review criteria and addressed questions of the effectiveness of pullout, classroom-based, and indirect–consultative service delivery models with elementary school–age children. Some evidence suggests that classroom-based direct services are at least as effective as pullout intervention for some intervention goals, and that highly trained speech-language pathology assistants, using manuals prepared by speech-language pathologists to guide intervention, can provide effective services for some children with language problems.

Conclusion

Lacking adequate research-based evidence, clinicians must rely on reason-based practice and their own data until more data become available concerning which service delivery models are most effective. Recommendations are made for an expanded research agenda.
First-principles calculation and transmission electron microscopy observation for hydrogen adsorption on carbon nanowalls
Authors: Kita Y. , Hayashi S. , Kinoshita I. , Tachibana M. , Tachikawa M. , Kobayashi K. , Tanimura M.
Published: July 2010

Transmission electron microscopy (TEM) technique was used to investigate the structure of carbon nanowalls (CNWs). The TEM observation clearly indicated the existence of the bended graphene structure in boundary regions between the crystallites of CNWs. According to this TEM result, the first-principles calculation was employed for the bended coronene molecule as the model of the boundary region between the crystallites of CNWs, to elucidate the mechanism of the hydrogen adsorption to CNWs. The hydrogen adsorption energies onto both on-top and hollow sites become greater as the bending angle increases, because the electronic structure of the carbon atom at the adsorption site changes from sp2 to sp3 hybridization character by natural bond orbital analysis. Our computational result is reasonably consistent with the specific feature of hydrogen adsorption to CNWs, which had been reported in our previous work by ultraviolet photoelectron spectroscopy and temperature program desorption measurements by Kinoshita et al.[Chem. Phys. Lett. 450, 360 (2008)].
Pulsed laser deposited Y3Fe5O12 films: Nature of magnetic anisotropy II
Authors: Manuilov S. A. , Grishin A. M.
Published: July 2010

Recently we found epitaxial Fe-deficient yttrium iron garnet Y3Fe5−tO12−3t/2 (YIG) films pulsed laser deposited onto the (111) and (001) face of Gd3Ga5O12 single crystal experience, respectively, strong rhombohedral and tetragonal distortions and possess unusual magnetic anisotropy. Using the crystal field theory, we explained these anomalies and showed in YIG(111) films ferric ion vacancies preferentially occupy octahedral complexes, order themselves along the [111] growth direction, cause rhombohedral lattice distortions, generate strong uniaxial and significantly reduce cubic crystalline anisotropy, Manuilov et al., [J. Appl. Phys. 106, 123917 (2009)]. Oxygen vacancies govern electrical neutrality and in spite of high concentration (in access of 7 at. %) they are perfectly ordered that is indicated by narrow ferromagnetic resonance linewidth. The present paper aims to compare growth anisotropies induced in (111) and (001) epitaxial Fe-deficient YIG films. Ordering of vacancies appeared to be different in (111) and (001) oriented YIG films. In highly Fe-deficient YIG(001) we found much smaller imbalance in redistribution of vacancies between the octa- and tetrahedral magnetic sublattices. This feature together with a weaker crystal field in tetrahedral Fe3+–O2− complexes result in reduced growth induced magnetic anisotropy in (001) oriented tetragonal distorted YIGs compared to rhombohedral distorted YIG(111) films.
Combined effects of Ga, N, and Al codoping in solution grown 3C–SiC
Authors: Sun J. W. , Zoulis G. , Lorenzzi J. C. , Jegenyes N. , Peyre H. , Juillaguet S. , Souliere V. , Milesi F. , Ferro G. , Camassel J.
Published: July 2010

We report on Ga-doped 3C–SiC epitaxial layers grown on on-axis (0001) 6H–SiC substrates using the vapor-liquid-solid technique and different Si1−xGax melts. The resulting samples have been investigated using secondary ion mass spectroscopy (SIMS), micro-Raman spectroscopy (μ-R) and, finally, low temperature photoluminescence (LTPL) spectroscopy. From SIMS measurements we find Ga concentrations in the range of 1018 cm−3, systematically accompanied by high nitrogen content. In good agreement with these findings, the μ-R spectra show that the Ga-doped samples are n-type, with electron concentrations close to 2×1018 cm−3. As expected, the LTPL spectra are dominated by strong N–Ga donor-acceptor pair (DAP) transitions. In one sample, a weak additional N–Al DAP recombination spectrum is also observed, showing the possibility to have accidental codoping with Ga and Al simultaneously. This was confirmed on a non-intentionally doped 3C–SiC (witness) sample on which, apart of the usual N and Al bound exciton lines, a small feature resolved at 2.35 eV comings from neutral Ga bound excitons. Quantitative analyses of the DAP transition energies in the Ga-doped and witness sample gave 346 meV for the optical binding energy of Ga acceptors in 3C–SiC against 251 meV for the Al one. The conditions for the relative observa-tion of Ga and Al related LTPL features are discussed and the demonstration of room temperature luminescence using Ga doping is done.
Determination of the role of O vacancy in Co:ZnO magnetic film
Authors: Yan Wensheng , Jiang Qinghua , Sun Zhihu , Yao Tao , Hu Fengchun , Wei Shiqiang
Published: July 2010

Annealing-induced changes in structural and magnetic property of Zn0.98Co0.02O thin film prepared at a low oxygen pressure by pulsed laser deposition have been studied with x-ray absorption fine structure, x-ray diffraction, and magnetization measurement. Intrinsic ferromagnetism at room temperature is observed for the as-deposited thin film, in which the Co ions are found to be substitutional for the Zn sites. Upon annealing in air, the occupation sites of Co ions keeps unchanged, whereas the magnetic property undergoes a dramatic change. X-ray absorption near-edge spectroscopy analysis and multiple-scattering calculations reveal that the change in magnetic property caused by annealing in air is due to the annihilation of the preformed oxygen vacancy. This study provides further evidence that O vacancy indeed plays an important role in activating the ferromagnetic interactions in Co-doped ZnO.
Optical switching of a metamaterial by temperature controlling
Authors: Huang Wan-xia , Yin Xiao-gang , Huang Cheng-ping , Wang Qian-jin , Miao Teng-fei , Zhu Yong-yuan
Published: July 2010

We have fabricated a metamaterial of metal/semiconductor/metal sandwich nanostrips structure comprising a pair of gold strips and a vanadium dioxide (VO2) strip. The optical response of the metamaterial has been studied. The results indicate the nanostructure with VO2 strips can be used as a temperature-controlling optical switch and the mechanism of this switch can be explained by the magnetic resonance.
Effect of structural relaxation and oxidation conditions on interlayer exchange coupling in Fe|MgO|Fe tunnel junctions
Authors: Yang H. X. , Chshiev M. , Kalitsov A. , Schuhl A. , Butler W. H.
Published: July 2010

The effect of structural relaxation and interfacial oxidation is demonstrated from first principles to have a crucial impact on interlayer exchange coupling (IEC) in crystalline Fe|MgO|Fe magnetic tunnel junctions (MTJs). It is shown that the IEC becomes antiferromagnetic for the relaxed structure in contrast to ferromagnetic for unrelaxed Fe|MgO|Fe MTJs. Furthermore, the antiferromagnetic IEC is strongly enhanced in the presence of oxygen vacancies while it is decreased by overoxidation and may even become ferromagnetic for sufficiently high oxygen concentration at the Fe∣MgO interface. These results were supported using a tight-binding model and provide an explanation for recent experimental studies.
Nanoscale space charge generation in local oxidation nanolithography
Authors: Chiesa Marco , Garcia Ricardo
Published: July 2010

We have measured the surface potential and the space charge generated during the first stages of atomic force microscopy field-induced oxidation. Space charge densities are about 1017 cm−3 for oxidation times below 10 ms. In a dry atmosphere, the surface potential is negative. However, in humid air the surface potential could be either positive or negative. This effect is attributed to a screening effect of the water molecules. These results explain and support the use of local oxidation patterns as templates for building molecular architectures. They also establish the space charge build up as an intrinsic feature in local oxidation experiments.
Effective light trapping in polycrystalline silicon thin-film solar cells by means of rear localized surface plasmons
Authors: Ouyang Zi , Pillai Supriya , Beck Fiona , Kunz Oliver , Varlamov Sergey , Catchpole Kylie R. , Campbell Patrick , Green Martin A.
Published: July 2010

Significant photocurrent enhancement has been achieved for evaporated solid-phase-crystallized polycrystalline silicon thin-film solar cells on glass, due to light trapping provided by Ag nanoparticles located on the rear silicon surface of the cells. This configuration takes advantage of the high scattering cross-section and coupling efficiency of rear-located particles formed directly on the optically dense silicon layer. We report short-circuit current enhancement of 29% due to Ag nanoparticles, increasing to 38% when combined with a detached back surface reflector. Compared to conventional light trapping schemes for these cells, this method achieves 1/3 higher short-circuit current.
Human antibodies reveal a protective epitope that is highly conserved among human and nonhuman influenza A viruses
Authors: Grandea Andres G. , Olsen Ole A. , Cox Thomas C. , Renshaw Mark , Hammond Philip W. , Chan-Hui Po-Ying , Mitcham Jennifer L. , Cieplak Witold , Stewart Shaun M. , Grantham Michael L. , Pekosz Andrew , Kiso Maki , Shinya Kyoko , Hatta Masato , Kawaoka Yoshihiro , Moyle Matthew
Published: July 2010

Influenza remains a serious public health threat throughout the world. Vaccines and antivirals are available that can provide protection from infection. However, new viral strains emerge continuously because of the plasticity of the influenza genome, which necessitates annual reformulation of vaccine antigens, and resistance to antivirals can appear rapidly and become entrenched in circulating virus populations. In addition, the spread of new pandemic strains is difficult to contain because of the time required to engineer and manufacture effective vaccines. Monoclonal antibodies that target highly conserved viral epitopes might offer an alternative protection paradigm. Herein we describe the isolation of a panel of monoclonal antibodies derived from the IgG
+
memory B cells of healthy, human subjects that recognize a previously unknown conformational epitope within the ectodomain of the influenza matrix 2 protein, M2e. This antibody binding region is highly conserved in influenza A viruses, being present in nearly all strains detected to date, including highly pathogenic viruses that infect primarily birds and swine, and the current 2009 swine-origin H1N1 pandemic strain (S-OIV). Furthermore, these human anti-M2e monoclonal antibodies protect mice from lethal challenges with either H5N1 or H1N1 influenza viruses. These results suggest that viral M2e can elicit broadly cross-reactive and protective antibodies in humans. Accordingly, recombinant forms of these human antibodies may provide useful therapeutic agents to protect against infection from a broad spectrum of influenza A strains.
Paired neuron recordings in the prefrontal and inferotemporal cortices reveal that spatial selection precedes object identification during visual search
Authors: Monosov Ilya E. , Sheinberg David L. , Thompson Kirk G.
Published: July 2010

We addressed the question of how we locate and identify objects in complex natural environments by simultaneously recording single neurons from two brain regions that play different roles in this familiar activity—the frontal eye field (FEF), an area in the prefrontal cortex that is involved in visual spatial selection, and the inferotemporal cortex (IT), which is involved in object recognition—in monkeys performing a covert visual search task. Although the monkeys reported object identity, not location, neural activity specifying target location was evident in FEF before neural activity specifying target identity in IT. These two distinct processes were temporally correlated implying a functional linkage between the end stages of ”where” and “what” visual processing and indicating that spatial selection is necessary for the formation of complex object representations associated with visual perception.
Optimum Runge-Kutta methods
Authors: Hull T. E. , Johnston R. L.
Published: July 2010

The optimum Runge-Kutta method of a particular order is the one whose truncation error is a minimum. Various measures of the size of the truncation error are considered. The optimum method is practically independent of the measure being used. Moreover, among methods of the same order which one might consider using the difference in size of the estimated error is not more than a factor of 2 or 3. These results are confirmed in practice insofar as the choice of optimum method is concerned, but they underestimate the variation in error between different methods.
Efficient algorithms for polynomial interpolation and numerical differentiation
Authors: Krogh Fred T.
Published: July 2010

Algorithms based on Newton’s interpolation formula are given for: simple polynomial interpolation, polynomial interpolation with derivatives supplied at some of the data points, interpolation with piecewise polynomials having a continuous first derivative, and numerical differentiation. These algorithms have all the advantages of the corresponding algorithms based on Aitken-Neville interpolation, and are more efficient.
Variations on variable-metric methods. (With discussion)
Authors: Greenstadt J.
Published: July 2010

In unconstrained minimization of a function

f
f

, the method of Davidon-FletcherPowell (a "variable-metric" method) enables the inverse of the Hessian

H
H

of

f
f

to be approximated stepwise, using only values of the gradient of

f
f

. It is shown here that, by solving a certain variational problem, formulas for the successive corrections to

H
H

can be derived which closely resemble Davidon’s. A symmetric correction matrix is sought which minimizes a weighted Euclidean norm, and also satisfies the "DFP condition." Numerical tests are described, comparing the performance (on four "standard" test functions) of two variationally-derived formulas with Davidon’s. A proof by Y. Bard, modelled on Fletcher and Powell’s, showing that the new formulas give the exact

H
H

after

N
N

steps, is included in an appendix.
Three-dimensional second-order accurate difference schemes for discontinuous hydrodynamic flows
Authors: Rubin Ephraim L. , Preiser Stanley
Published: July 2010

In this paper, we show how a second-order accurate two-step method used in the numerical computation of hydrodynamic flows may be derived directly from the integral conservation laws. A necessary and sufficient condition for stability for the linearized equations is derived for the three-dimensional Cartesian coordinate case.
The incomplete beta function and its ratio to the complete beta function
Authors: Osborn David , Madey Richard
Published: July 2010

The incomplete beta function,
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper B Subscript x Baseline left-parenthesis p comma q right-parenthesis equals integral Subscript 0 Superscript x Baseline y Superscript p minus 1 Baseline left-parenthesis 1 minus y right-parenthesis Superscript q minus 1 Baseline d y">

B
x

(
p
,
q
)
=
∫

0
x

y

p
−
1

(
1
−
y

)

q
−
1

d
y

{B_x}(p,q) = \int {_0^x} {y^{p - 1}}{(1 - y)^{q - 1}}dy

, and its ratio to the complete beta function

B
1

(
p
,
q
)

{B_1}(p,q)

has been calculated on an IBM-7044 computer to five significant figures and tabulated for the arguments p and q each in the interval from 0.5 to 2.0 with increments of 0.05 and for the parameter

x
x

in the interval 0.1 to 1.0 with increments of 0.01. The function was evaluated by first expanding a factor of the integrand in a binomial series and then integrating each term. In order to facilitate computation, one expansion is taken for

x
≦
1

/

2

x \leqq 1/2

and another for

1

/

2
>
x
≦
1

1/2 > x \leqq 1

. The expansions are truncated when the relative error is less than or equal to an arbitrarily predetermined fraction. Typical running time for achieving five significant figures on the IBM-7044 is about one minute for

10
4

{10^4}

values.
mbmdr: an R package for exploring gene–gene interactions associated with binary or quantitative traits
Authors: Calle M. Luz , Urrea Víctor , Malats Núria , Van Steen Kristel
Published: July 2010

Summary: We describe mbmdr, an R package for implementing the model-based multifactor dimensionality reduction (MB-MDR) method. MB-MDR has been proposed by Calle et al. as a dimension reduction method for exploring gene–gene interactions in case-control association studies. It is an extension of the popular multifactor dimensionality reduction (MDR) method of Ritchie et al. allowing a more flexible definition of risk cells. In MB-MDR, risk categories are defined using a regression model which allows adjustment for covariates and main effects and, in addition to the classical low risk and high risk categories, MB-MDR considers a third category of indeterminate or not informative cells. An important improvement added to the current mbmdr algorithm with respect to the original MB-MDR formulation in Calle et al. and also to the classical MDR approach, is the extension of the methodology to different outcome types. While MB-MDR was initially proposed for binary traits in the context of case-control studies, the mbmdr package provides options to analyze both binary or quantitative traits for unrelated individuals.

Availability:  http://cran.r-project.org/

Contact:  malu.calle@uvic.cat

Supplementary information:  Supplementary data are available at Bioinformatics online.
Perioperative Hypothermia (33°C) Does Not Increase the Occurrence of Cardiovascular Events in Patients Undergoing Cerebral Aneurysm Surgery
Authors: Nguyen Hoang P. , Zaroff Jonathan G. , Bayman Emine O. , Gelb Adrian W. , Todd Michael M. , Hindman Bradley J.
Published: July 2010

Background

Perioperative hypothermia has been reported to increase the occurrence of cardiovascular complications. By increasing the activity of sympathetic nervous system, perioperative hypothermia also has the potential to increase cardiac injury and dysfunction associated with subarachnoid hemorrhage.

Methods

The Intraoperative Hypothermia for Aneurysm Surgery Trial randomized patients undergoing cerebral aneurysm surgery to intraoperative hypothermia (n = 499, 33.3 degrees +/- 0.8 degrees C) or normothermia (n = 501, 36.7 degrees +/- 0.5 degrees C). Cardiovascular events (hypotension, arrhythmias, vasopressor use, myocardial infarction, and others) were prospectively followed until 3-month follow-up and were compared in hypothermic and normothermic patients. A subset of 62 patients (hypothermia, n = 33; normothermia, n = 29) also had preoperative and postoperative (within 24 h) measurement of cardiac troponin-I and echocardiography to explore the association between perioperative hypothermia and subarachnoid hemorrhage-associated myocardial injury and left ventricular function.

Results

There was no difference between hypothermic and normothermic patients in the occurrence of any single cardiovascular event or in composite cardiovascular events. There was no difference in mortality (6%) between groups, and there was only a single primary cardiovascular death (normothermia). There was no difference between hypothermic and normothermic patients in postoperative versus preoperative left ventricular regional wall motion or ejection fraction. Compared with preoperative values, hypothermic patients had no postoperative increase in cardiac troponin-I (median change 0.00 microg/l), whereas normothermic patients had a small postoperative increase (median change + 0.01 microg/l, P = 0.038).

Conclusion

In patients undergoing cerebral aneurysm surgery, perioperative hypothermia was not associated with an increased occurrence of cardiovascular events.
Properties of the phage-shock-protein (Psp) regulatory complex that govern signal transduction and induction of the Psp response in Escherichia coli
Authors: Jovanovic Goran , Engl Christoph , Mayhew Antony J. , Burrows Patricia C. , Buck Martin
Published: July 2010

The phage-shock-protein (Psp) response maintains the proton-motive force (pmf) under extracytoplasmic stress conditions that impair the inner membrane (IM) in bacterial cells. InEscherichia colitranscription of thepspABCDEandpspGgenes requires activation ofσ54-RNA polymerase by the enhancer-binding protein PspF. A regulatory network comprising PspF–A–C–B–ArcB controlspspexpression. One key regulatory point is the negative control of PspF imposed by its binding to PspA. It has been proposed that under stress conditions, the IM-bound sensors PspB and PspC receive and transduce the signal(s) to PspA via protein–protein interactions, resulting in the release of the PspA–PspF inhibitory complex and the consequent induction ofpsp. In this work we demonstrate that PspB self-associates and interacts with PspC via putative IM regions. We present evidence suggesting that PspC has two topologies and that conserved residue G48 and the putative leucine zipper motif are determinants required for PspA interaction and signal transduction upon stress. We also establish that PspC directly interacts with the effector PspG, and show that PspG self-associates. These results are discussed in the context of formation and function of the Psp regulatory complex.
THIS ARTICLE HAS BEEN RETRACTED: Spinal 2‐chloroprocaine: effective dose for ambulatory surgery
Authors: SELL A. , TEIN T. , PITKÄNEN M.
Published: July 2010

Background: There is an interest in finding a safe, short‐acting spinal anaesthetic, suitable for ambulatory surgery. In this prospective study, we evaluated the effective dose of plain 2‐chloroprocaine (2‐CP) for lower limb surgery, including knee arthroscopy and saphenectomy.

Methods: Sixty‐four ASA physical status I–III patients undergoing elective lower limb surgery were randomly allocated to one of the four local anaesthetic groups for spinal anaesthesia in a double‐blind manner. The patients (n=16 patients in each group) received 35, 40, 45 or 50 mg of 10 mg/ml isobaric 2‐CP.

Results: In all patients, anaesthesia was sufficient for the planned surgery. The median peak block height (T9) was similar in all four groups (P=0.66). Time to complete sensory block regression was faster in the 35 mg group (111 min, mean) and in the 40 mg group (108 min) than in the 50 mg group (134 min, P=0.005). No differences in time to complete motor block regression were observed (P=0.3). Home discharge time was faster in the 35 mg group (123 min) and in the 40 mg group (122 min) than in the 50 mg group (165 min, P=0.001). No complications related to spinal anaesthesia were observed and no transient neurologic symptoms (TNS) were reported at the 3‐day follow‐up.

Conclusion: Spinal 2‐CP, 10 mg/ml 35, 40, 45 and 50 mg provide reliable sensory and motor block for ambulatory surgery, while reducing the dose of 2‐CP to 35 and 40 mg resulted in a spinal block of faster ambulation.
Social communication difficulties and autism spectrum disorder in young children with optic nerve hypoplasia and/or septo‐optic dysplasia
Authors: PARR JEREMY R , DALE NAOMI J , SHAFFER LARA M , SALT ALISON T
Published: July 2010

Aim  The aim of this study was to study systematically social, communication, and repetitive/restrictive (SCRR) behavioural difficulties and clinical autism spectrum disorder (ASD) in children with optic nerve hypoplasia (ONH) and/or septo‐optic dysplasia (SOD), and to investigate the relationship between visual impairment, SCRR difficulties, ASD, and cognition.

Method  A case‐note study of clinic records from a specialist developmental vision service was completed. Standardized assessments of vision and development and clinician judgements about SCRR difficulties and clinical ASD were made by a multidisciplinary team.

Results  A total of 45 females and 38 males (mean age 3y 5mo; range 10mo–6y 10mo) with ONH or SOD and profound visual impairment (PVI) or severe visual impairment (SVI) were assessed. A total of 58% of children had at least one SCRR difficulty, and 31% had a clinical diagnosis of ASD. The prevalence of ASD was slightly higher in children with SOD than in children with ONH (36% vs 26%) also slightly more frequent in children with PVI than in children with SVI (36% vs 27%). The prevalence of SCRR difficulties was statistically higher in children with PVI than in children with SVI (p=0.003). Clinical ASD was most likely to be diagnosed between 2 years 4 months and 4 years 6 months. Development was significantly delayed in children with ASD compared with children without social communication difficulties (p=0.001).

Interpretation  Children with SVI or PVI are at risk of SCRR difficulties and clinical ASD. Children with ONH and/or SOD and visual impairment have a similar risk of developing clinical ASD as other visual impairment groups. However, ASD prevalence data from this study are a minimum estimate, as some young children may have developed ASD behaviours in later childhood. Developmental surveillance for children with ONH and/or SOD should continue until at least the age of 4 years 6 months.
Biodiverse, a tool for the spatial analysis of biological and related diversity
Authors: Laffan Shawn W. , Lubarsky Eugene , Rosauer Dan F.
Published: July 2010

Biodiverse is a tool for the spatial analysis of diversity using indices based on taxonomic, phylogenetic and matrix (e.g. genetic dissimilarity) relationships. The explosion in georeferenced biological specimen and survey data means there is an increasing need for such tools. Biodiverse supports four processes: 1) linked visualisation of data distributions in geographic, taxonomic, phylogenetic and matrix spaces; 2) spatial moving window analyses including richness, endemism, phylogenetic diversity and beta diversity; 3) spatially constrained agglomerative cluster analyses; and 4) randomisations for hypothesis testing. Biodiverse is open‐source and supports user developed extensions. It can be used both through a graphical user interface and scripts. Biodiverse can be downloaded from .
Exercise and Supraphysiological Dose of Nandrolone Deconoate Increase Apoptosis in Spermatogenic Cells
Authors: Shokri Saeed , Aitken Robert John , Abdolvahhabi Mirabbas , Abolhasani Farid , Ghasemi Fahimeh Mohammad , Kashani Iraj , Ejtemaeimehr Shahram , Ahmadian Shahin , Minaei Bagher , Naraghi Mohammad Ali , Barbarestani Mohammad
Published: July 2010

Abstract: Anabolic‐androgenic steroids are used at high doses by athletes for improving athletic ability, physical appearance and muscle mass. Unfortunately, the abuse of these agents has significantly increased. It has been established that exercise and high doses of anabolic‐androgenic steroids may influence the hypothalamic‐pituitary‐gonadal axis, which can in turn affect testicular apoptosis. However, the effect of the combination of exercise and high dose of anabolic‐androgenic steroids on testicular apoptosis is not known. We investigated the combined effects of exercise and high doses of nandrolone decanoate on apoptosis in the spermatogenic cell lineage. Five groups of male Wistar strain albino rats were treated as follows for 8 weeks: solvent of nandrolone decanoate (peanut oil) as a vehicle (Sham); nandrolone decanoate (10 mg/kg/weekly) (nandrolone decanoate); exercise (1 hr/day, 5 days a week) (exercise); nandrolone decanoate (10 mg/kg/weekly) and exercise (1 hr/day, 5 days a week) (nandrolone decanoate exercise); and sedentary control without any injection or exercise (Control). Apoptosis in the male germ line was characterized by TUNEL, caspase‐3 assay and transmission electron microscopy. The weights of the testis and accessory sex organs, as well as sperm parameters significantly decreased in the experimental groups relative to the sham and control groups (p ≤ 0.05). Germ cell apoptosis and a significant decrease in the number of germ cell layers in nandrolone decanoate exercise‐treated testes were observed (p ≤ 0.05). Exercise training seems to increase the extent of apoptotic changes caused by supraphysiological dose of nandrolone decanoate in rats, which in turn affects fertility.
Literature Review of Methods for Mitigating Hydroelastic Response of VLFS Under Wave Action
Authors: Wang C. M. , Tay Z. Y. , Takagi K. , Utsunomiya T.
Published: July 2010

Presented herein is a literature review on the design and performance of antimotion structures/devices such as breakwaters, submerged plates, oscillating water column breakwaters, air-cushion, auxiliary attachments, and mechanical joints for mitigating the hydroelastic response of very large floating structures (VLFS) under wave action. Shapes of VLFS that could minimize the hydrodynamic response of the structure are also discussed. The analytical, numerical, and experimental methods used in studying the effect of these antimotion structures/devices toward reducing the hydroelastic responses of VLFS are also reviewed.
Homogenization Techniques and Micromechanics. A Survey and Perspectives
Authors: Charalambakis Nicolas
Published: July 2010

In this paper, we present a critical survey on homogenization theory and related techniques applied to micromechanics. The validation of homogenization results, the characterization of composite materials and the optimal design of complex structures are issues of great technological importance and are viewed here as a combination of mathematical and mechanical homogenization. The mathematical tools for modeling sequentially layered composites are explained. The influence of initial and boundary conditions on the effective properties in nonlinear problems is clarified and the notion of stability by homogenization is analyzed. Multiscale micromechanics methods are outlined and the classical as well as the emerging analytical and computational techniques are presented. Computation of effective static and dynamical properties of materials with linear or nonlinear constitutive equations is closely related to the development of generalized theories such as the strain-gradient mechanics. Selected applications of these techniques are outlined. Moreover, the extension of kinetic techniques in homogenization and the related inverse imaging problem are presented.
Recent Studies on Buckling of Carbon Nanotubes
Authors: Wang C. M. , Zhang Y. Y. , Xiang Y. , Reddy J. N.
Published: July 2010

This paper reviews recent research studies on the buckling of carbon nanotubes. The structure and properties of carbon nanotubes are introduced to the readers. The various buckling behaviors exhibited by carbon nanotubes are also presented herein. The main factors, such as dimensions, boundary conditions, temperature, strain rate, and chirality, influencing the buckling behaviors are also discussed, as well as a brief introduction of the two most used methods for analyzing carbon nanotubes, i.e., continuum models and atomistic simulations. Summary and recommendations for future research are also given. Finally, a large body of papers is given in the reference section. It is hoped that this paper provides current knowledge on the buckling of carbon nanotubes, reviews the computational methods for determining the buckling loads, and inspires researchers to further investigate the buckling properties of carbon nanotubes for practical applications.
The Peach Bottom area in the Pennsylvania-Maryland Piedmont
Authors: Faill Rodger T. , Smith Robert C.
Published: July 2010

The Appalachian Piedmont in south-central Pennsylvania and north-central Maryland contains metasedimentary siliciclastic rocks (phyllites to quartzites) that were deposited largely offshore of Laurentia, prior to and during the early history of the Iapetan Ocean. The Peach Bottom area is centered on the belt of Peach Bottom Slate and overlying Cardiff Quartzite, which is surrounded by the late Neoproterozoic and early Paleozoic rocks of the Peters Creek and Scott Creek (new name) Formations. Their provenance was the Brandywine and Baltimore microcontinents that lay farther offshore of the Laurentian coast. This area also includes an ophiolitic mélange that formed in front of an advancing island arc in Iapetus. All these rocks lay largely undisturbed throughout much of the Paleozoic, experiencing only chlorite-grade greenschist facies metamorphism through deep burial. Alleghanian thrusting associated with the growth of the Tucquan anticline imparted their present widespread, monocline, steep southeast dip of the bed-parallel foliation.
Current-Activated, Pressure-Assisted Densification of Materials
Authors: Garay J.E.
Published: July 2010

This review of current-activated, pressure-assisted densification (CAPAD) focuses on both fundamental and practical issues. We provide some useful background for researchers interested in the process and critically assess the state of the technique.
Heterogeneous Integration of Compound Semiconductors
Authors: Moutanabbir Oussama , Gösele Ulrich
Published: July 2010

The ability to tailor compound semiconductors and to integrate them onto foreign substrates can lead to superior or novel functionalities with a potential impact on various areas in electronics, optoelectronics, spintronics, biosensing, and photovoltaics. This review provides a brief description of different approaches to achieve this heterogeneous integration, with an emphasis on the ion-cut process, also known commercially as the Smart-Cut™ process. This process combines semiconductor wafer bonding and undercutting using defect engineering by light ion implantation. Bulk-quality heterostructures frequently unattainable by direct epitaxial growth can be produced, provided that a list of technical criteria is fulfilled, thus offering an additional degree of freedom in the design and fabrication of heterogeneous and flexible devices. Ion cutting is a generic process that can be employed to split and transfer fine monocrystalline layers from various crystals. Materials and engineering issues as well as our current understanding of the underlying physics involved in its application to cleaving thin layers from freestanding GaN, InP, and GaAs wafers are presented.
The Indentation Size Effect: A Critical Examination of Experimental Observations and Mechanistic Interpretations
Authors: Pharr George M. , Herbert Erik G. , Gao Yanfei
Published: July 2010

The indentation size effect is one of several size effects on strength for which “smaller is stronger.” Through use of geometrically self-similar indenters such as cones and pyramids, the size effect is manifested as an increase in hardness with decreasing depth of penetration and becomes important at depths of less than approximately 1 μm. For spherical indenters, the diameter of the sphere is the most important length scale; spheres with diameters of less than approximately 100 μm produce measurably higher hardnesses. We critically review experimental observations of the size effect, focusing on the behavior of crystalline metals, and examine prevailing ideas on the mechanisms responsible for the effect in light of recent experimental observations and computer simulations.
Microfluidic Synthesis of Polymer and Inorganic Particulate Materials
Authors: Park Jai Il , Saffari Amir , Kumar Sandeep , Günther Axel , Kumacheva Eugenia
Published: July 2010

This article reviews recent developments in the microfluidic preparation of different types of particles made of polymeric and inorganic materials. We discuss control of the particle sizes, morphologies, shapes, and structures in terms of various features of microfluidic synthesis.
Optimal Design of Heterogeneous Materials
Authors: Torquato S.
Published: July 2010

This article reviews recent inverse techniques that we have devised to optimize the structure and macroscopic properties of heterogeneous materials such as composite materials, porous media, colloidal dispersions, and polymer blends. Optimization methods provide a systematic means of designing materials with tailored properties and microstructures for a specific application. This article focuses on two inverse problems that are solved via optimization techniques: (a) the topology optimization procedure used to design heterogeneous materials and (b) stochastic optimization methods employed to reconstruct or construct microstructures.
Oxide Thermoelectric Materials: A Nanostructuring Approach
Authors: Koumoto Kunihito , Wang Yifeng , Zhang Ruizhi , Kosuga Atsuko , Funahashi Ryoji
Published: July 2010

Thermoelectric power generation technology is now expected to help overcome global warming and climate change issues by recovering and converting waste heat into electricity, thus improving the total efficiency of energy utilization and suppressing the consumption of fossil fuels that are supposedly the major sources of CO2 emission. Thermoelectric oxides, composed of nontoxic, naturally abundant, light, and cheap elements, are expected to play a vital role in extensive applications for waste heat recovery in an air atmosphere. This review article summarizes our previous and ongoing studies on SrTiO3-based materials and further discusses nanostructuring approaches for both SrTiO3 and CaMnO3 materials. ZnMnGaO4 is taken as a model case for constructing a self-assembled nanostructure. The present status of thermoelectric oxide module development is also introduced and discussed.
Self-Healing Polymers and Composites
Authors: Blaiszik B.J. , Kramer S.L.B. , Olugebefola S.C. , Moore J.S. , Sottos N.R. , White S.R.
Published: July 2010

Self-healing polymers and fiber-reinforced polymer composites possess the ability to heal in response to damage wherever and whenever it occurs in the material. This phenomenal material behavior is inspired by biological systems in which self-healing is commonplace. To date, self-healing has been demonstrated by three conceptual approaches: capsule-based healing systems, vascular healing systems, and intrinsic healing polymers. Self-healing can be autonomic—automatic without human intervention—or may require some external energy or pressure. All classes of polymers, from thermosets to thermoplastics to elastomers, have potential for self-healing. The majority of research to date has focused on the recovery of mechanical integrity following quasi-static fracture. This article also reviews self-healing during fatigue and in response to impact damage, puncture, and corrosion. The concepts embodied by current self-healing polymers offer a new route toward safer, longer-lasting, fault-tolerant products and components across a broad cross section of industries including coatings, electronics, transportation, and energy.
An Assessment of AKIN Criteria for Hospital-Acquired Acute Kidney Injury: A Prospective Observational Cohort Study
Authors: Kwon Soon Hyo , Noh Hyunjin , Jeon Jin Seok , Kim Yongbae , Han Dong Cheol
Published: July 2010

Background and Aims: The Acute Kidney Injury Network (AKIN) criteria assert a new definition for acute kidney injury (AKI). We investigated the incidence of hospital-acquired AKI, along with the clinical characteristics and outcomes in hospitalized patients according to AKIN stage. Methods: We performed a prospective, observational, single-center study. We monitored serum creatinine everyday for all patients using a hospital data survey system during the study period from September 2007 to February 2008. Results: Hospital-acquired AKI occurred in 1.2% of all hospitalized patients during the study period. Among patients with AKI, 29.2% were in stage 1, 36.5% were in stage 2 and 34.4% were in stage 3. A significantly higher rate of renal recovery was observed in patients with lower-stage injuries (71.4, 60.0, and 21.2% for stages 1, 2, and 3, respectively). Mortality for patients with stage 3 AKI (51.5%) was significantly higher than that for patients with stages 1 or 2 (p < 0.013). Independent risk factors for mortality in patients with AKI included malignancy, stage 3 AKI, diuretic use, and intensive care unit admission prior to AKI. Conclusions: Our findings support the utility of the AKIN criteria for hospital-acquired AKI, and demonstrate that stage 3 AKI poses a significant risk for poor patient and renal outcomes.
Cognitive Profile of Chronic Kidney Disease and Hemodialysis Patients without Dementia
Authors: Post James B. , Jegede Adejoke B. , Morin Kel , Spungen Ann M. , Langhoff Erik , Sano Mary
Published: July 2010

Background/Aims: The high risk and prevalence of dementia among patients with chronic kidney disease (CKD) and in those receiving hemodialysis (HD) may be preceded by mild cognitive impairment (MCI). We aimed to assess cognitive function in CKD and HD patients with no history of stroke or dementia, in order to identify and characterize early cognitive deficits. Methods: 24 CKD and 27 HD male outpatients without history of cerebrovascular or neurodegenerative disease underwent comprehensive neuropsychological testing in an observational cross-sectional study. Test results were used to categorize patients into MCI subtypes. Results: All subjects scored ≧28 on the Mini-Mental State Examination. The prevalence of executive function was at least 25% in both groups and memory impairment occurred in 13% of the HD patients and 15% of those with CKD. MCI occurred in 76% of the group and HD patients showed a higher prevalence of MCI compared to CKD patients (89 vs. 63%) with a preponderance (>70%) of cases across both groups classified as non-amnestic MCI. Conclusion: Predialysis CKD and HD patients have a high prevalence of MCI despite normal global cognitive function. MCI was more prevalent among the HD patients and deficits more frequently resulted in non-amnestic MCI.
Moderate Chronic Kidney Disease in Women Is Associated with Fracture Occurrence Independently of Osteoporosis
Authors: Kinsella Sinead , Chavrimootoo Shawn , Molloy Michael G. , Eustace Joseph A.
Published: July 2010

Background: Chronic kidney disease (CKD) is associated with increased risk of fragility fracture but whether this is independent of osteoporosis is unclear. Methods: We conducted a retrospective cross-sectional study of 1,702 female patients referred for dual-energy X-ray absorptiometry (DXA) scanning (Lunar IDXA) between September 2006 and April 2007. Estimated glomerular filtration rate (eGFR; ml/min/1.73 m2) by Modification of Diet in Renal Disease was calculated within 1 year (median interval 4 weeks) of the DXA scan. The independent association of self-reported fracture occurrence with eGFR category was assessed using multivariate logistic regression. Results: Mean age (SD) was 61.7 (10.8) years; mean eGFR (SD) was 68.8 (12.2). The percentages of subjects with an eGFR of 75–89, 60–74, 30–59 and <30 was 34, 45, 20 and 0.8%, respectively. Forty-seven percent had osteoporosis. Mean T scores for the above eGFR categories were –2.2, –2.3, –2.5 and –3.0, respectively (p trend <0.001). Osteoporosis was significantly associated with eGFR on univariate analysis but not following adjustment for age. The percentage of patients with a fracture (29%) and with multiple prior fractures (3.5%) was higher at lower eGFR (p < 0.001, χ2 test). The adjusted odds ratios (95% confidence interval) of any prior fracture for eGFR 75–89, 60–74 and 30–59 were 1.0 (reference), 1.2 (0.9–1.6) and 1.4 (1.0–1.9), respectively, adjusting simultaneously for age, T score, risk factors and treatment for osteoporosis. Conclusion: Moderate CKD is a significant independent predictor of fracture occurrence.
High Expression of Vascular Endothelial Growth Factor in EV71-Infected Patients Does Not Originate from EV71-Infected Cells
Authors: Huang Shu-Chen , Raghavaraju Giri , Liu Hsiao-Sheng
Published: July 2010

Background: Enterovirus (EV) 71 is an important pathogen causing death in children under 5 years of age worldwide. However, the core pathogenesis remains elusive. We reveal that the protein expression level of vascular endothelial growth factor (VEGF) in EV71 patients was 2-fold higher than in normal controls. However, the origin of VEGF in EV71-infected patients remains unclear. Methods: VEGF mRNA and protein expression in four EV71-infected cell lines was evaluated by RT-PCR, ELISA and Western blotting. Results: We found that only mRNA expression of VEGF was increased in the infected cells. Intra- and extracellular VEGF protein expression was decreased or unchanged in the four infected cell lines compared with the uninfected and inactivated EV71-infected cells. Conclusions: Our data reveal that EV71 infection of four human cell lines induced VEGF mRNA expression but did not induce VEGF protein expression in the infected cells. Therefore, the increased VEGF protein expression in EV71-infected patients may be due to the influence of surrounding non-infected cells following stimulation of proinflammatory cytokines secreted from the infected cells.
Characterization of the Duck Plague Virus UL35 Gene
Authors: Cai Ming-Sheng , Cheng An-Chun , Wang Ming-Shu , Chen Wan-Ping , Zhang Xian , Zheng Shang-Xi , Pu Yang , Lou Kun-Peng , Zhang Yao , Sun Lei , Wang Lu-Lu , Zhu De-Kang , Luo Qi-Hui , Chen Xiao-Yue
Published: July 2010

Objective: Previous study has demonstrated that the duck plague virus (DPV) UL35 gene can be expressed as a recombinant fusion protein, and the prepared antiserum has a high reactivity and specificity against the purified recombinant protein. In the present study, to elucidate the properties and functions of its encoding protein, the UL35 gene product (VP26) was identified by using the prepared rabbit polyclonal antiserum. Methods: Real-time PCR, Western blot and immunofluorescence analysis were used to determine the transcription and expression kinetics and subcellular localization of DPV VP26 in DPV-infected cells. Results: A protein of approximately 13 kDa that reacted with the antiserum was detected in immunoblot of DPV-infected cellular lysates. Real-time PCR and Western blot analysis of DPV-infected cells showed that VP26 was produced predominantly at the late stage of infection, its production was highly dependent on viral DNA synthesis, and the UL35 gene was regulated as a late viral gene, suggesting that the gene should be categorized as γ2 class. Additionally, analysis of the association of DPV VP26 with purified virions revealed that VP26 was a component of extracellular mature DPV virions. Subcellular localization demonstrated that VP26 firstly localized in cytoplasm, then it transferred to the nucleus and aggregated in the punctate region of the nucleus in DPV-infected cells. Conclusion: Taken together, these results will provide a foundation for further functional analysis of the DPV UL35 gene.