bluuebunny/crossref_metadata_2025 huggingface dataset:
Low dose of propranolol does not affect rat osteotomy healing and callus strength
Authors: Smitham Peter , Crossfield Lawrence , Hughes Gillian , Goodship Allen , Blunn Gordon , Chenu Chantal
Published: April 2014

Experimental studies suggest that the β‐blocker propranolol stimulates bone formation but little work has investigated its effect on fracture healing. In this study, we examined if a low dose of propranolol, previously shown to be preventive against bone loss in rats, improves bone repair. Female Wistar rats were injected with saline or propranolol (0.1 mg/kg/day) (n = 20/group), 5 days a week for 8 weeks. Three weeks after the beginning of treatment, all rats underwent a mid‐diaphyseal transverse osteotomy in the left femur. Radiographic analysis of ostetomy healing was performed 2 and 5 weeks after osteotomy. Rats were sacrificed at 5 weeks and femora collected for measurements of fracture strength by torsional testing, callus volume, and mineral content by micro‐CT analysis and histology of fracture callus. Eighty nine percent of osteotomies achieved apparent radiological union by 5 weeks in both groups. Propranolol treatment did not significantly alter the torsional strength of the fractured femur compared with controls. The volume and mineralization of fracture callus at 5 weeks were not significantly different in both groups. Histology showed that endochondral ossification was not affected by propranolol. Altogether, our results demonstrate that propranolol using the regimen described does not significantly improve or inhibit rat osteotomy healing and mechanical strength. © 2014 The Authors. Journal of Orthopaedic Research Published by Wiley Periodicals, Inc. J Orthop Res 32:887–893, 2014.
Pilot test of a patient decision aid about liver transplant organ quality
Authors: Volk Michael L. , Roney Meghan , Fagerlin Angela
Published: April 2014

Prior studies have shown that patients are reluctant to accept donor-specific risks, and transplant professionals lack an effective and time-efficient means of obtaining informed consent. We designed and pilot-tested a Web-based patient decision aid (DA) on organ quality. The DA was administered to 53 liver transplant candidates (median Model for End-Stage Liver Disease score = 14, range = 7-26), and they took a mean of 15 minutes to complete it. Questions about knowledge and attitudes were asked before and after the DA. Subjects' knowledge improved, with 53% and 60% correctly answering questions about hepatitis B virus and human immunodeficiency virus transmission before the DA and 94% and 100%, respectively, correctly answering them afterward (P < 0.001). The accuracy of mortality prediction also improved from a mean 3-month mortality estimate of 22% before the DA to 12% afterward (P < 0.001). After the DA, subjects felt that it was more likely that they might be offered a less-than-perfect liver (P = 0.001), and they were more likely to consider accepting such a liver (P < 0.001). In conclusion, implementing a Web-based patient DA is feasible and improves knowledge among liver transplant candidates. The use of this tool may decrease candidates' reluctance to accept extended criteria organs. Liver Transpl 20:850-855, 2014. © 2014 AASLD.
Self‐Assembly of Polyrotaxanes Synthesized Via Click Chemistry of Azido‐Endcapped PNIPAAm‐b‐Pluronic F68‐b‐PNIPAAm/γ‐CD with Propargylamine‐Substituted β‐CDs
Authors: Jiang Lan , Ye Lin , Zhang Ai‐ying , Feng Zeng‐guo
Published: April 2014

A kind of γ‐(cyclodextrin) (γ‐CD)‐based polyrotaxane (PR) is synthesized via an aqueous click reaction between propargylamine‐substituted β‐CD and polypseudorotaxanes (PPRs) self‐assembled from azido‐endcapped PNIPAAm‐b‐Pluronic F68‐b‐PNIPAAm with a varying amount of γ‐CD. The evolution of the self assembly, dependent on the preparation process, is observable by X‐ray diffraction (XRD) and DSC analyses. The γ‐CD is able to be included and preferably entrapped on the PNIPAAm blocks, showing a unique loose‐fit aggregate structure after the click reaction. Most γ‐CDs gradually slip over to the middle PPG block of Pluronic F68, giving rise to a characteristic channel‐type crystal structure in the dialy­sis process. In addition, the lower critical solution temperature (LCST) is sharply enhanced due to the coverage of the remaining γ‐CDs hindering the thermally responsive aggregation of the PNIPAAm blocks.

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Long non‐coding RNA 91H contributes to the occurrence and progression of esophageal squamous cell carcinoma by inhibiting IGF2 expression
Authors: Gao Tianyi , He Bangshun , Pan Yuqin , Xu Yeqiong , Li Rui , Deng Qiwen , Sun Huilin , Wang Shukui
Published: April 2014

Long non‐coding RNAs (lncRNAs) have been recently recognized as a major class of regulators in mammalian systems. 91H, a novel long noncoding antisense transcripts located on the position of the H19/IGF2 locus has been suggested to play a potential tumor‐suppressor role in tumor development. However, little study has proved the mechanism in esophageal squamous cell carcinoma (ESCC). We carried out this study to explore the role of lncRNA 91H in the regulation of H19 imprinting control regions (ICR) and IGF2 expression and the association between 91H and ESCC progression. The cell line TE‐1, Eca‐109, and 232 ESCC patients' matched sets of paraffin‐embedded adjacent normal and tumor samples were obtained in this study. The results showed that 91H expression was significantly lower in patients with higher depth of invasion, neoplastic grading and TNM which usually leads to the overexpression of IGF2 in tumor progression. The expression of 91H usually decreased in TE‐1 and Eca‐109 when treated with demethylation agent. Further analysis revealed that, in 91H knockdown cell lines, IGF2 expression was also significantly higher than negative controls. Therefore, the results demonstrated that the lncRNA 91H was associated with H19 ICR methylation and inhibited IGF2 expression of ESCC patients which may optimize the mechanism of IGF2 regulation in tumor development. Patients with higher depth of invasion, neoplastic grading and TNM usually demonstrated lower 91H expression potentially represent a novel clinically relevant event to identify individuals at increased risk for the occurrence, progression and prognosis of ESCC. © 2014 Wiley Periodicals, Inc.
Abnormal dorsal premotor–motor inhibition in writer's cramp
Authors: Pirio Richardson Sarah , Beck Sandra , Bliem Barbara , Hallett Mark
Published: April 2014

The authors hypothesized that a deficient premotor–motor inhibitory network contributes to the unwanted involuntary movements in dystonia. The authors studied nine controls and nine patients with writer's cramp (WC). Dorsal premotor–motor cortical inhibition (dPMI) was tested by applying conditioning transcranial magnetic stimulation (TMS) to the dorsal premotor cortex and then a test pulse to the ipsilateral motor cortex at an interval of 6 ms. The authors used an H‐reflex in flexor carpi radialis paired with TMS over the premotor cortex to assess for spinal cord excitability change. Finally, the authors interrupted a choice reaction time task with TMS over dorsal premotor cortex to assess performance in a nondystonic task. The results showed that WC patients exhibited dPMI at rest (88.5%, the ratio of conditioned to unconditioned test pulse), in contrast to controls, who did not show dPMI (109.6%) (P = 0.0198). This difference between patients and controls persisted during contraction (100% vs. 112%) and pen‐holding (95.6% vs. 111%). The H‐reflex in the arm was not modulated by the premotor cortex stimulation. The WC patients made more errors, and the error rate improved with TMS over the premotor cortex. These results suggest that abnormal premotor–motor interactions may play a role in the pathophysiology of focal dystonia. The dPMI was not modulated by task in either group, but was constantly greater in the patients. The significance of the increased inhibition is likely to be compensatory. It appears to be a robust finding and, in combination with other features, could be further explored as a biomarker. © 2014 International Parkinson and Movement Disorder Society
Computational coupling of moisture diffusion and mechanical deformation in polymer matrix composites
Authors: Bailakanavar M. , Fish J. , Aitharaju V. , Rodgers W.
Published: April 2014

A computationally efficient multiscale–multiphysics model aimed at predicting mechanical response of thermoplastic composites subjected to different levels of moisture was developed. The mathematical model of the coupled moisture‐diffusion–mechanical‐deformation phenomenon was stated at the microscale, based on the observed experimental data, and then upscaled using a mathematical homogenization approach. A two‐way coupling between moisture diffusion and mechanical deformation was introduced by which diffusivity was enhanced by hydrostatic strain, whereas strength and stiffness were assumed to degrade because of moisture ingression, which also gives rise to swelling. The computational complexity of analyzing the two coupled physical processes at multiple scales was reduced via a model reduction scheme for multiple physical processes. The model was validated for 30% by weight filled glass fiber and carbon fiber reinforced thermoplastic composites. The moisture conditioning and uniaxial tension experiments were utilized to identify diffusion and mechanical properties at a fine scale. The identified properties were then used to validate the formulation in the three‐point bending test. Copyright © 2014 John Wiley & Sons, Ltd.
A novel approach to representative orientation distribution functions for modeling and simulation of polycrystalline shape memory alloys
Authors: Junker P.
Published: April 2014

A micromechanical model for polycrystalline shape memory alloys (SMAs) was introduced in a series of papers by Hackl and coauthors. In order to model the polycrystalline aspect, they assumed a specific set of orientation distribution functions that had to be resolved with high numerical effort. Although this model displays interesting aspects, its use to simulate macroscopic specimens is problematic due to the long calculation time.

In this paper, we present a new approach to modeling and simulation of polycrystalline SMAs that is based on parameterization of a class of orientation distribution functions by using only a few parameters. A variational concept is applied to derive evolution equations for these parameters. The resultant material model drastically reduces the calculation time and may thus provide an approach to efficient micromechanical simulation of specimens that are of engineering interest.

This study presents a variety of different numerical examples, such as pseudoelastic and pseudoplastic material behavior for CuAlNi and NiTi SMAs, to demonstrate the broad applicability of the material model. The numerical benefit of the presented modeling approach is demonstrated by comparative calculations of the new model versus the previous model. Copyright © 2014 John Wiley & Sons, Ltd.
Dimensional reduction of nonlinear finite element dynamic models with finite rotations and energy‐based mesh sampling and weighting for computational efficiency
Authors: Farhat Charbel , Avery Philip , Chapman Todd , Cortial Julien
Published: April 2014

A rigorous computational framework for the dimensional reduction of discrete, high‐fidelity, nonlinear, finite element structural dynamics models is presented. It is based on the pre‐computation of solution snapshots, their compression into a reduced‐order basis, and the Galerkin projection of the given discrete high‐dimensional model onto this basis. To this effect, this framework distinguishes between vector‐valued displacements and manifold‐valued finite rotations. To minimize computational complexity, it also differentiates between the cases of constant and configuration‐dependent mass matrices. Like most projection‐based nonlinear model reduction methods, however, its computational efficiency hinges not only on the ability of the constructed reduced‐order basis to capture the dominant features of the solution of interest but also on the ability of this framework to compute fast and accurate approximations of the projection onto a subspace of tangent matrices and/or force vectors. The computation of the latter approximations is often referred to in the literature as hyper reduction. Hence, this paper also presents the energy‐conserving sampling and weighting (ECSW) hyper reduction method for discrete (or semi‐discrete), nonlinear, finite element structural dynamics models. Based on mesh sampling and the principle of virtual work, ECSW is natural for finite element computations and preserves an important energetic aspect of the high‐dimensional finite element model to be reduced. Equipped with this hyper reduction procedure, the aforementioned Galerkin projection framework is first demonstrated for several academic but challenging problems. Then, its potential for the effective solution of real problems is highlighted with the realistic simulation of the transient response of a vehicle to an underbody blast event. For this problem, the proposed nonlinear model reduction framework reduces the CPU time required by a typical high‐dimensional model by up to four orders of magnitude while maintaining a good level of accuracy. Copyright © 2014 John Wiley & Sons, Ltd.
Biophysical markers for abnormal placentation: first and/or second trimester
Authors: Farina Antonio
Published: April 2014

Placental development is a major cause of a successful pregnancy, and in the presence of placental dysfunction, there is a higher risk of pregnancy complications. Doppler technology can be used for screening and detecting the more common pregnancy‐associated diseases like preeclampsia, intrauterine growth retardation, and perinatal loss. In this review, the biophysical markers are discussed in the light of the latest information that appeared in the medical literature. © 2014 John Wiley & Sons, Ltd.
Project System Vulnerability to Political Risks in International Construction Projects: The Case of Chinese Contractors
Authors: Deng Xiaopeng , Pheng Low Sui , Zhao Xianbo
Published: April 2014

This study aims to explore the variables affecting the project system vulnerability to political risks in international construction projects. A questionnaire survey was conducted and 138 responses were received from both academia and industry. The exploratory factor analysis was then adopted to uncover the relationships among these variables. The results showed that three exposure factors (i.e., attribute-based exposure, strategy-based exposure, and transaction-based exposure) and three capacity factors (i.e., core competitive capacity, relative bargain capacity, and integrate adaptive capacity) were believed to be the significant underlying factors for the project system vulnerability to political risks. Also, case studies were conducted and the results indicated that the emergent framework was suitable and tractable for application in the future. This study provides a method for measuring the project system vulnerability to political risks; thus, international construction enterprises can decrease their risk exposure and enhance their capacity for dealing with political risks in international construction projects.
The Effects of Incentive Mechanism on Knowledge Management Performance in China: The Moderating Role of Knowledge Attributes
Authors: Zhang Lianying , Zhang Zhen
Published: April 2014

Knowledge management of a new product development project team is critical for a firm's competitive advantage, and incentive mechanism is one of the most effective knowledge management drives. In this paper, we examined the effects of non-financial incentive and team-based financial incentive on knowledge management performance in China and identified the moderating effects of knowledge attributes (codifiability and teachability). Our findings indicate that non-financial incentive and team-based financial incentive have positive effects on knowledge management performance. Codifiability and teachability enhance the team-based financial incentive–knowledge management performance relationship. Finally, implications for research and practice are discussed.
Mutual Caring—Resolving Habituation through Awareness: Supporting Meaningful Learning from Projects
Authors: Jugdev Kam , Wishart Paul
Published: April 2014

This study used Grounded Theory methodology and developed an emergent theory of Mutual Caring. The main concern was Habituation to ineffective lessons learned sharing practices. Habituation is resolved through Mutual Caring, a socially and psychologically adaptive process. Mutual Caring involves comfortable conversations, engaging/sharing, and developing self-confidence, resulting in an enhanced wisdom pool. This paper extends the emphasis on tangible knowledge-sharing mechanisms. Mutual Caring could lead to better outcomes, such as more accessible and usable knowledge, a project management wisdom pool, and criteria for improved dyadic relationships to enhance project learning.
What you Should Know about Megaprojects and Why: An Overview
Authors: Flyvbjerg Bent
Published: April 2014

This paper takes stock of megaproject management, an emerging and hugely costly field of study, by first answering the question of how large megaprojects are by measuring them in the units of mega, giga, and tera, and concluding with how we are presently entering a new “tera era” of trillion-dollar projects. Second, total global megaproject spending is assessed, at US$6 to US$9 trillion annually, or 8% of the total global gross domestic product (GDP), which denotes the biggest investment boom in human history. Third, four “sublimes”—political, technological, economic, and aesthetic—are identified and used to explain the increased size and frequency of megaprojects. Fourth, the “iron law of megaprojects” is laid out and documented: Over budget, over time, over and over again. Moreover, the “break–fix model” of megaproject management is introduced as an explanation of the iron law. Fifth, Albert O. Hirschman's theory of the “Hiding Hand” is revisited and critiqued as unfounded and corrupting for megaproject thinking in both the academy and policy. Sixth, it is shown how megaprojects are systematically subject to “survival of the unfittest,” which explains why the worst projects get built rather than the best. Finally, it is argued that the conventional way of managing megaprojects has reached a “tension point,” in which tradition is being challenged and reform is emerging.
Synthesis and property of polyoxazolidone having fluorene moiety by polyaddition of diisocyanate and diepoxide
Authors: Azechi Motohisa , Endo Takeshi
Published: April 2014

Polyoxazolidones having fluorenyl group were synthesized by polyaddition of 9,9‐diglycidyl fluorene with various diisocyanates. The polymer from 9,9‐diglycidyl fluorene and methylenediphenyl 4,4′‐diisocyanate was afforded in high yield although polydispersity of the polymer was found relatively broad. The IR spectrum of the obtained polymer showed two absorption in carbonyl region. One of them was assigned to the expected oxazolidone, while the other at 1710 cm−1 appeared due to a carbonyl group of the isocyanurate moieties produced by cyclotrimerization of isocyanate. It is assumed that the cyclotrimerization would cause the broad polydispersity caused by the branched structure formed by isocyanurate. The polymers obtained with three kinds of diisocyanates (methylenediphenyl 4,4'‐diisocyanate, 1,6‐hexamethylene diisocyanate, 1,4‐phenylene diisocyanate) showed high thermal stability, as their Td10 was depended on the structure of diisocyanate. All polymers had high transparency in a visible region. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1755–1760
Examining pediatric emergency home ventilation practices in home health nurses: Opportunities for improved care
Authors: Kun Sheila S. , Beas Virginia N. , Keens Thomas G. , Ward Sally S.L. , Gold Jeffrey I.
Published: April 2014

Objectives

To assess the pediatric home health nurses' knowledge in tracheostomy and ventilator emergency care on home mechanical ventilation (HMV).

Background

Emergencies are frightening experiences for solo home health nurses and require advanced skills in emergency response and care, especially in pediatric patients who pose unique challenges.

Working Hypothesis

Nurses with greater years of nursing experience would perform better on emergency HMV case‐based scenarios than nurses with less years of experience.

Study Design

An exploratory online survey was used to evaluate emergency case‐based pediatric scenarios. Demographic and professional experiences were profiled.

Patient‐subject Selection

Seventy‐nine nurses had an average of 6.73 (SD = 1.41) years in pediatric nursing. Over 70% received their HMV training in their agency, 41% had less than 4 years of experience, and 30.4% had encountered at least one emergency situation at home.

Methodology

The online survey was distributed by managers of 22 home health agencies to nurses providing pediatric HMV care.

Results

Nurses scored an average of 4.87 out of 10 possible points. There were no significant differences between nurses with <4 years of experience versus those with more experience on ventilator alarms knowledge or total knowledge. Ninety‐seven percent of the nurses favored more training in HMV from a variety of settings (e.g., agency, on‐line training).

Conclusions

Nurses did not perform well in case‐based ventilator alarm scenarios. Length of nursing experience did not differentiate greater knowledge. It is clear that nurses require and want more training in emergency‐based HMV. Recommendations for an enhanced curriculum are suggested. Pediatr Pulmonol. 2015; 50:691–697. © 2014 Wiley Periodicals, Inc.
Control of density of CdSe quantum dots grown by MEE on MgS
Authors: Rajan Akhil , Moug Richard T. , Davidson Ian A. , Prior Kevin A.
Published: April 2014

CdSe quantum dots were grown on MgS barrier layers by migration enhanced epitaxy. Following depositon of CdSe at 240 °C, the layers were annealed at 320 °C. In this study the annealing time was varied along with a delay time introduced between the CdSe deposition and the high temperature anneal.

By varying just these two parameters the CdSe dot density measured by AFM could be varied by one order of magnitude. A short growth delay of just one minute between deposition and annealing was particularly effective and gave the lowest CdSe dot density reported so far of ∼40 × 108cm–2. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improved transport properties for ZnO films on Al2O3(11$\bar2$0) by MOCVD
Authors: Hiragino Y. , Furubayashi Y. , Moriyama K. , Fujita Y.
Published: April 2014

ZnO films on Al2O3 (112$\bar2$0) with excellent transport properties were grown using metalorganic chemical vapor deposition (MOCVD) with a high speed rotating disk and a separated showerhead. Diisopropylzinc and tert ‐butanol were used as Zn and O precursors, respectively. Hall‐effect measurements revealed that the ZnO films in this work showed a high mobility of 140 cm2/Vs and a low carrier concentration of 1.5×1017 cm–3, both of which are comparable to those grown by molecular beam epitaxy or pulsed laser deposition. This report should open a way to the mass production of single crystalline ZnO films which should be usable for optoelectronic devices. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrically driven single photon emission from a CdSe/ZnSSe/MgS semiconductor quantum dot
Authors: Quitsch Wolf , Kümmell Tilmar , Gust Arne , Kruse Carsten , Hommel Detlef , Bacher Gerd
Published: April 2014

We demonstrate electrically driven single photon emission from a CdSe/ZnSSe/MgS single quantum dot embedded in a resonant cavity light emitting diode. Patterned Pd/Au top contacts are used to inject the charge carriers locally. Single quantum dot electroluminescence is obtained at T = 4 K from nanoapertures lithographically defined in the top contacts. At low current densities, antibunching with a value of g(2)(0) = 0.16 is achieved. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of zinc oxide on pyrolytic graphite sheet by electrochemical and mist chemical vapor depositions
Authors: Kake Shunsuke , Uno Kazuyuki , Furotani Ikuhiro , Makabe Harutaka , Yamasaki Yuichiro , Tanaka Ichiro
Published: April 2014

Growth of zinc oxide (ZnO) on pyrolytic graphite sheet (PGS) by electrochemical deposition (ECD) and mist chemical vapor deposition (CVD) was investigated in the viewpoint of crystal orientations. We examined the fullwidth at half‐maximum (FWHM) of X‐ray rocking curve profiles of graphite 0002 and ZnO 0002 diffractions for the investigations. In the case of ECD, thermal annealing at 400, 800, and 1000 °C for PGS before the growth reduced the FWHM value of the grown ZnO.

On the other hand, in the case of mist CVD, the growth process and an etching process which may flatten the surface roughness simultaneously occurred. As a result, the FWHM values of the grown ZnO and the PGS were almost the same. These results indicate that each ZnO grain was grown on each graphite grain along with a same c‐orientation direction. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Heavily n‐type ZnO: A plasmonic material at telecommunication wavelengths
Authors: Kalusniak Sascha , Sadofev Sergey , Schäfer Peter , Henneberger Fritz
Published: April 2014

Doping of ZnO by Ga allows for generation of free electrons up to concentrations of about 1021 cm–3 without significant deterioration of the crystal structure. In this way, a metallic dielectric function is formed with a negative real part tuneable from the mid infrared up to telecommunication wavelengths. The losses are about one order of magnitude lower than in traditional metals.

We demonstrate surface plasmon polaritons with dispersion relations that can be engineered in a unique way by utilizing epitaxial multi‐layer structures of different doping level. In contrast to the standard air/metal excitations, the surface‐plasmon‐polariton frequency approaches a finite value in the zero‐wavevector limit at metal/metaltype interfaces. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Inhibition of LPS‐Induced TNF‐α and NO Production in Mouse Macrophage and Inflammatory Response in Rat Animal Models by a Novel Ayurvedic Formulation, BV‐9238
Authors: Dey Debendranath , Chaskar Sunetra , Athavale Nitin , Chitre Deepa
Published: April 2014

Rheumatoid arthritis is a chronic crippling disease, where protein‐based tumor necrosis factor‐alpha (TNF‐α) inhibitors show significant relief, but with potentially fatal side effects. A need for a safe, oral, cost‐effective small molecule or phyto‐pharmaceutical is warranted. BV‐9238 is an Ayurvedic poly‐herbal formulation containing specialized standardized extracts of Withania somnifera, Boswellia serrata, Zingiber officinale and Curcuma longa. The anti‐inflammatory and anti‐arthritic effects of BV‐9238 were evaluated for inhibition of TNF‐α and nitric oxide (NO) production, in lipopolysaccharide‐stimulated, RAW 264.7, mouse macrophage cell line. BV‐9238 reduced TNF‐α and NO production, without any cytotoxic effects. Subsequently, the formulation was tested in adjuvant‐induced arthritis (AIA) and carrageenan‐induced paw edema (CPE) rat animal models. AIA was induced in rats by injecting Freund's complete adjuvant intra‐dermally in the paw, and BV‐9238 and controls were administered orally for 21 days. Arthritic scores in AIA study and inflamed paw volume in CPE study were significantly reduced upon treatment with BV‐9238. These results suggest that the anti‐inflammatory and anti‐arthritic effects of BV‐9238 are due to its inhibition of TNF‐α, and NO, and this formulation shows promise as an alternate therapy for inflammatory disorders where TNF‐α and NO play important roles. Copyright © 2014 John Wiley & Sons, Ltd.
Concise Review: Mechanotransduction via p190RhoGAP Regulates a Switch Between Cardiomyogenic and Endothelial Lineages in Adult Cardiac Progenitors
Authors: Kshitiz  , Afzal Junaid , Kim Deok-Ho , Levchenko Andre
Published: April 2014

Mechanical cues can have pleiotropic influence on stem cell shape, proliferation, differentiation, and morphogenesis, and are increasingly realized to play an instructive role in regeneration and maintenance of tissue structure and functions. To explore the putative effects of mechanical cues in regeneration of the cardiac tissue, we investigated therapeutically important cardiosphere-derived cells (CDCs), a heterogeneous patient- or animal-specific cell population containing c-Kit+ multipotent stem cells. We showed that mechanical cues can instruct c-Kit+ cell differentiation along two lineages with corresponding morphogenic changes, while also serving to amplify the initial c-Kit+ subpopulation. In particular, mechanical cues mimicking the structure of myocardial extracellular matrix specify cardiomyogenic fate, while cues mimicking myocardium rigidity specify endothelial fates. Furthermore, we found that these cues dynamically regulate the same molecular species, p190RhoGAP, which then acts through both RhoA-dependent and independent mechanisms. Thus, differential regulation of p190RhoGAP molecule by either mechanical inputs or genetic manipulation can determine lineage type specification. Since human CDCs are already in phase II clinical trials, the potential therapeutic use of mechanical or genetic manipulation of the cell fate could enhance effectiveness of these progenitor cells in cardiac repair, and shed new light on differentiation mechanisms in cardiac and other tissues. Stem Cells  2014;32:1999–2007
LiSbS2‐mC16: Structure Determination from X‐ray Powder Diffraction Data
Authors: Huber Sebastian , Pfitzner Arno
Published: April 2014

Monoclinic LiSbS2‐mC16 was synthesized by solid‐state reaction of Li2S, Sb, and S in the ratio 1:2:5 at a temperature of 900 °C. The excess of sulfur serves as a kind of flux and is not incorporated in the structure. The product is air and moisture sensitive. The crystal structure of the dark red product was determined from X‐ray powder diffraction data at 293 K. LiSbS2‐mC16 crystallizes in the space group C2/c (no. 15) with a = 8.0205(8) Å, b = 7.9243(8) Å, c = 6.6987(7) Å, β = 126.303(6)°, V = 343.11(7) Å3, and Z = 4. It forms an ordered NaCl type superstructure, which shows two different sites for the cations, whereas the cubic high temperature modification cF8 exhibits only one position with a mixed occupation by lithium and antimony. Lithium has a slightly distorted octahedral coordination by sulfur. The distortion of the octahedral coordination polyhedron is much stronger in the case of antimony. Therefore it is better described as a 2 + 2 + 2 coordination mode.
Sexual Function and Body Image are Similar after Laparoscopy‐Assisted and Open Ileal Pouch–Anal Anastomosis
Authors: Kjaer Mie Dilling , Laursen Stig Borbjerg , Qvist Niels , Kjeldsen Jens , Poornoroozy Peiman Hossein
Published: April 2014

Background

Ileal pouch–anal anastomosis (IPAA) is performed in patients with ulcerative colitis and familial adenomatous polyposis where the majority of patients are sexually active. Laparoscopic surgery is becoming the preferred technique for most colorectal interventions, and we examined postoperative sexual function and body image compared to those after open surgery IPAA.

Methods

Patients treated with IPAA in the period from October 2008 to March 2012 were included. Evaluation of sexual function, body image, and quality of life was performed using the Female Sexual Function Index (FSFI), the International Index of Erectile Function (IIEF), the Body Image Questionnaire (BIQ), and the Short Inflammatory Bowel Disease Questionnaire (SIBDQ).

Results

We included 72 patients (38 laparoscopy‐assisted and 34 open). Response rate was 74 %. There were no differences in demographics, functional outcome, quality of life (SIBDQ score: 53 vs. 53), or time of follow‐up (637 vs. 803 days). All women and men showed scores above the cutoff line of normal sexual function. There was no significant difference in sexual function between the laparoscopic and open groups. We found no differences in BIQ between open and laparoscopic IPAA; however, there was a tendency toward lower postoperative self‐esteem among women compared to men (p = 0.07). We also found a tendency toward a better body image among laparoscopy‐treated women compared to open‐treated women (p = 0.07).

Conclusions

Although there might be a tendency toward better body image among laparoscopy‐treated women, the two surgical techniques seem equal with respect to postoperative sexual function.
Lysosomal diseases: diagnostic update
Authors: Winchester Bryan
Published: April 2014

Technological developments in newborn and population screening, biomarker discovery for monitoring treatment and rapid high throughput DNA sequencing are having a great impact on the diagnostic procedure for symptomatic patients with lysosomal storage diseases. The use of dried blood spots, initially for newborn screening, has stimulated the introduction of automated, rapid and more sensitive methods for the assay of lysosomal enzymes, including the synthesis of novel substrates. Storage products and secondary metabolites in urine and cells can be identified and measured very accurately and sensitively by high performance liquid chromatography and tandem mass spectrometry. This has enhanced the preliminary metabolite screen for LSDs and facilitated the diagnosis of transport defects. Fast, reliable and affordable high throughput DNA sequencing, such as whole or selected exome sequencing, is helping to make diagnoses in difficult cases, to reveal novel gene defects, to widen the clinical spectrum of diseases and possibly to identify modifying genetic factors. Bioinformatics will be necessary to handle the data generated by these new technologies. Notwithstanding, these technical innovations, accurate and reliable diagnosis will still depend on the knowledge and experience of skilled laboratory staff.
Anabolic exercise in haemodialysis patients: a randomised controlled pilot study
Authors: Kirkman Danielle L. , Mullins Paul , Junglee Naushad A. , Kumwenda Mick , Jibani Mahdi M. , Macdonald Jamie H.
Published: April 2014

Background

The anabolic response to progressive resistance exercise training (PRET) in haemodialysis patients is unclear. This pilot efficacy study aimed to determine whether high‐intensity intradialytic PRET could reverse atrophy and consequently improve strength and physical function in haemodialysis patients. A second aim was to compare any anabolic response to that of healthy participants completing the same program.

Methods

In a single blind controlled study, 23 haemodialysis patients and 9 healthy individuals were randomly allocated to PRET or an attention control (SHAM) group. PRET completed high‐intensity exercise leg extensions using novel equipment. SHAM completed low‐intensity lower body stretching activities using ultra light resistance bands. Exercises were completed thrice weekly for 12 weeks, during dialysis in the haemodialysis patients. Outcomes included knee extensor muscle volume by magnetic resonance imaging, knee extensor strength by isometric dynamometer and lower body tests of physical function. Data were analysed by a per protocol method using between‐group comparisons.

Results

PRET elicited a statistically and clinically significant anabolic response in haemodialysis patients (PRET—SHAM, mean difference [95 % CI]: 193[63 to 324] cm3) that was very similar to the response in healthy participants (PRET—SHAM, 169[−41 to 379] cm3). PRET increased strength in both haemodialysis patients and healthy participants. In contrast, PRET only enhanced lower body functional capacity in the healthy participants.

Conclusions

Intradialytic PRET elicited a normal anabolic and strength response in haemodialysis patients. The lack of a change in functional capacity was surprising and warrants further investigation.
Geochemistry of metamorphic rocks of the Kurai block (Gorny Altai)
Authors: Kuibida Ya.V. , Kruk N.N. , Gusev N.I. , Vladimirov V.G. , Demonterova E.I.
Published: April 2014

We consider the primary nature and sources of the protoliths of metamorphic rocks of the Kurai block located in the large Teletskoe–Kurai system of deep faults separating the Gorny Altai and West Sayan structures. It has been established that the protoliths of the Kurai block metapelites were deposits of transitional crust: They lack typical rocks of mature continental crust (arkoses, litharenites) and have reduced (relative to the upper continental crust) contents of lithophile elements and elevated contents of transition elements. The average Nd model age of the protoliths of the metapelites of the Kurai complex corresponds to the Middle Riphean (1.4–1.6 Ga). The metabasites of the Kurai complex are similar in petrologic composition to metamorphic products of oceanic basalts. It is shown that the formation of metamorphic associations of the Kurai block was caused by tectonometamorphic transformations of a compositionally heterogeneous rock unit (basalts, aluminous and volcanomict sediments), which were, most likely, a fragment of Middle Cambrian–Early Ordovician turbidite basin with an oceanic basement.
Water content in minerals of mantle xenoliths from the Udachnaya pipe kimberlites (Yakutia)
Authors: Ragozin A.L. , Karimova A.A. , Litasov K.D. , Zedgenizov D.A. , Shatsky V.S.
Published: April 2014

Distribution of water among the main rock-forming nominally anhydrous minerals of mantle xenoliths of peridotitic and eclogitic parageneses from the Udachnaya kimberlite pipe, Yakutia, has been studied by IR spectroscopy. The spectra of all minerals exhibit vibrations attributed to hydroxyl structural defects. The content of H2O (ppm) in minerals of peridotites is as follows: 23–75 in olivine, 52–317 in orthopyroxene, 29–126 in clinopyroxene, and 0–95 in garnet. In eclogites, garnet contains up to 833 ppm H2O, and clinopyroxene, up to 1898 ppm (~ 0.19 wt.%). The obtained data and the results of previous studies of minerals of mantle xenoliths show wide variations in H2O contents both within different kimberlite provinces and within the Udachnaya kimberlite pipe. Judging from the volume ratios of mineral phases in the studied xenoliths, the water content varies over narrow ranges of values, 38–126 ppm. At the same time, the water content in the studied eclogite xenoliths is much higher and varies widely, 391–1112 ppm.
Error analysis of frequency-dependent magnetic susceptibility measurements: magnetic viscosity studies with the Bartington MS2 system
Authors: Kozhevnikov N.O. , Kamnev Ya.K. , Kazansky A.Yu.
Published: April 2014

Magnetic viscosity of rocks associated with magnetic relaxation of ultrafine ferrimagnetic mineral grains (superparamagnetism) is employed in magnetic grain size measurements. Magnetic viscosity is most often estimated from dual frequency measurements of magnetic susceptibility. The measured susceptibility values bear uncertainty that comprises two components: an instrument error and a drift. The instrument error refers to the accuracy of the measurement system and shows how precise the data are in ideal operation conditions. This error affects especially the low susceptibilities of weak samples, which thus should be measured on a high sensitivity range. Drift is due to external factors, such as changes in the temperature of sensors and/or samples, as well as in the orientation of the samples relative to the sensor, vibration, electromagnetic noise, etc. Drift, more critical for measurements on strong samples, is manageable by the operator. To reduce drift, every effort should be made to maintain suitable ‘quiet’ operation conditions.
Forgotten accounts of historical earthquakes in Siberia (17th and 18th centuries) by J.G. Gmelin
Authors: Nikonov A.A. , Fleifel L.D.
Published: April 2014

This contribution represents the first Russian publication and in-depth analysis of accounts by J.G. Gmelin of earthquakes in Siberia from the late 17th and the first three decades of the 18th centuries. These forgotten accounts, though short and fragmentary, expand the existing database and enable new solutions of some of the problematic aspects in the study of seismicity in this region.
Fractional dynamics of tethered particles in oscillatory Stokes flows
Authors: Lim Edwin A. , Kobayashi Marcelo H. , Coimbra Carlos F. M.
Published: April 2014

A mechanistic model for the low-Reynolds-, high-Strouhal-number behaviour of a system consisting of a spherical particle attached to an inelastic tether under uniform sinusoidal cross-flow is presented. Unsteady history drag and virtual mass effects are considered for both the sphere and the tether. The mechanics of the problem is such that the resulting coupled fractional differential equations are linear and solvable analytically. The stationary solutions obtained in this work show that there are limiting dimensions for the length and thickness of the tether when compared to the radius of the particle that allow for the motion of the particle–tether system to simulate the motion of a free particle. These conditions exist for the range of small oscillation amplitudes that are required for keeping the particle Reynolds number smaller than unity while oscillating the particle–tether system at high frequencies (Strouhal numbers larger than unity). The fractional order model for the particle–tether system is compared against detailed experimental results for tethered particles for a wide range of experimental frequencies, including the low-frequency range where tether effects are measurable.
Deep-sea Ampharetidae (Polychaeta) from Capbreton Canyon (north-east Atlantic) with the description of a new species
Authors: Aguirrezabalaga Florencio , Parapar Julio
Published: April 2014

During the Capbreton cruises (1987–1990), samples of bathyal benthic macrofauna were taken at 37 stations situated along the continental slope (480–1113 m depth) of the Capbreton Canyon (Bay of Biscay, north-east Atlantic). Ten species of polychaetes belonging to six genera (Melinna, Eclysippe, Amphicteis,Anobothrus, GlyphanostomumandTanseimaruana) of the family Ampharetidae Malmgren, 1866 were collected at 13 of these stations. Most of these species are reported for the first time in the area.Amphicteisaff.wesenbergaeis reported for the first time after its recent description and a new species belonging to the genusGlyphanostomumis here described. Moreover, the finding ofMelinna monoceroidesrepresents the northernmost record of the species;Tanseimaruana vestisis recorded for the second time from the East Atlantic after its recent finding in Icelandic waters;Anobothrusaff.gracilisis reported for the second time from the Iberian Peninsula, representing, the southernmost record of the species in the Atlantic Ocean. The potential identification of two fragments of an Ampharetinae indet asAnobothrus laubieri, a deep water Arctic species, is discussed.
A new genus of Colletteidae (Crustacea: Peracarida: Tanaidacea) from the Pacific with comments on dimorphic males with species specific characters
Authors: Larsen Kim , Araújo-Silva Catarina
Published: April 2014

A new genus and species of Tanaidacea are described from the manganese nodule province between the Clarion and the Clipperton Fracture Zone of the equatorial North Pacific Ocean collected during the French/German BIONOD expedition in 2012. The new genus,Cheliasetosatanais, can be diagnosed by the propodal and dactylus setation and the maxilliped endite armament. The male is also described and, while being a dimorphic swimming male, still shares the diagnostic characters and posseses a fully functional maxilliped.
A meta-analysis of the prevalence of attention deficit hyperactivity disorder in incarcerated populations
Authors: Young S. , Moss D. , Sedgwick O. , Fridman M. , Hodgkins P.
Published: April 2014

Background

Studies report the variable prevalence of attention deficit hyperactivity disorder (ADHD) in incarcerated populations. The aim of this meta-analysis was to determine the prevalence of ADHD in these populations.

Method

Primary research studies reporting the prevalence (lifetime/current) of ADHD in incarcerated populations were identified. The meta-analysis used a mixed log-binomial model, including fixed effects for each covariate and a random study effect, to estimate the significance of various risk factors.

Results

Forty-two studies were included in the analysis. ADHD prevalence was higher with screening diagnoses versus diagnostic interview (and with retrospective youth diagnoses versus current diagnoses). Using diagnostic interview data, the estimated prevalence was 25.5% and there were no significant differences for gender and age. Significant country differences were noted.

Conclusions

Compared with published general population prevalence, there is a fivefold increase in prevalence of ADHD in youth prison populations (30.1%) and a 10-fold increase in adult prison populations (26.2%).
Paradoxes and Challenges for China's Forests in the Reform Era
Authors: Robbins Alicia S.T. , Harrell Stevan
Published: April 2014

China's relatively recent dramatic increase in forest area has been hailed domestically and globally as one of the world's few environmental success stories, but significant problems remain in China's reforestation efforts. We describe the challenges that China still faces if it is to meet its laudable – but sometimes contradictory – goals for its forest sector: improving rural livelihoods, sustaining and restoring ecosystem services, and increasing output of the forest product-dependent manufacturing and construction sectors. We do so while pointing out the unintended consequences of implementing these policy goals: overstatement of the quantity and quality of the forest recovery, domestic human and ecological costs of the reforestation, and externalization of China's continually growing demand for timber and forest products in the form of increased imports from vulnerable forests in other parts of the world.
The Firstk-Regular Subgraph is Large
Authors: GAO PU
Published: April 2014

Let$(G_m)_{0\le m\le \binom{n}{2}}$be the random graph process starting from the empty graph on vertex set [n] and with a random edge added in each step. Letmkdenote the minimum integer such thatGmkcontains ak-regular subgraph. We prove that for all sufficiently largek, there exist two constants εk≥ σk> 0, with εk→ 0 ask→ ∞, such that asymptotically almost surely anyk-regular subgraph ofGmkhas size between (1 − εk)|${\mathcal C}_k$| and (1 − σk)|${\mathcal C}_k$|, where${\mathcal C}_k$denotes thek-core ofGmk.
The Rightful Demise of the Sh*t Sandwich: Providing Effective Feedback
Authors: James Ian Andrew
Published: April 2014

Background: As a trainee cognitive therapist in the early 1990s, I was taught the Sh*t Sandwich by my supervisor. I continued to use this technique for many years without seeing the need to extend my repertoire of feedback strategies. Aims: This article describes a number of other feedback techniques, raising awareness of the processes underpinning feedback, and facilitating reflection on feedback methods. Method: This review examines feedback and the methods of feedback used to improve clinical competence. Results: Evidence informs us that the use of good feedback has a significant effect on learners’ outcomes (Milne, 2009). However, despite recognition of its importance, many supervisors fail to give adequate feedback and utilize methods that are sub-optimal. One such problematic method is the notorious “Sh*t Sandwich” (SS), which attempts to hide criticism within a cushion of two positive statements. This paper looks at various models of giving negative and positive feedback, suggesting that our repertoire of feedback methods may require expanding. Conclusion: The review suggests that feedback is a complex process and methods that place an emphasis on the learner as an active participant in the learning process (i.e. interactive approaches) should be encouraged. The paper suggests that negative feedback should generally be avoided in favour of constructive support, accompanied by specific, descriptive, balanced feedback, with new learning being consolidated by role play. Generally, feedback should be given about the task rather than the person, but when it is personalized it should relate to effort rather than ability.