bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards constraining the magnitude of global agricultural sediment and soil organic carbon fluxes
Authors: Doetterl Sebastian , Van Oost Kristof , Six Johan
Published: December 2011

Reliable quantitative data on the extent and rates of soil erosion are needed to understand the global significance of soil‐erosion induced carbon exchange and to underpin the development of science‐based mitigation strategies, but large uncertainties remain. Existing estimates of agricultural soil and soil organic carbon (SOC) erosion are very divergent and span two orders of magnitude. The main objective of this study was to test the assumptions underlying existing assessments and to reduce the uncertainty associated with global estimates of agricultural soil and SOC erosion. We parameterized a simplified erosion model driven by coarse global databases using an empirical database that covers the conterminous USA. The good agreement between our model results and empirical estimates indicate that the approach presented here captures the essence of agricultural erosion at the scales of continents and that it may be used to predict the significance of erosion for the global carbon cycle and its impact on soil functions. We obtained a global soil erosion rate of 10.5 Mg ha‐1 y‐1 for cropland and 1.7 Mg ha‐1 y‐1 for pastures. This corresponds to SOC erosion rates of 193 kg C ha‐1 y‐1 for cropland and 40.4 kg C ha‐1 y‐1 for eroding pastures and results in a global flux of 20.5 (±10.3) Pg y‐1 of soil and 403.5 (±201.8) Tg C y‐1. Although it is difficult to accurately assess the uncertainty associated with our estimates of global agricultural erosion, mainly due to the lack of model testing in (sub‐)tropical regions, our estimates are significantly lower than former assessments based on the extrapolation of plot experiments or global application of erosion models. Our approach has the potential to quantify the rate and spatial signature of the erosion‐induced disturbance at continental and global scales: by linking our model with a global soil profile database, we estimated soil profile modifications induced by agriculture. This showed that erosion‐induced changes in topsoil SOC content are significant at a global scale (an average SOC loss of 22% in 50 years) and agricultural soils should therefore be considered as dynamic systems that can change rapidly. Copyright © 2011 John Wiley & Sons, Ltd.
Convective‐radiative fins with simultaneous variation of thermal conductivity, heat transfer coefficient, and surface emissivity with temperature
Authors: Aziz A. , Torabi Mohsen
Published: December 2011

This paper is a numerical study of thermal performance of a convective‐radiative fin with simultaneous variation of thermal conductivity, heat transfer coefficient, and surface emissivity with temperature. The convective heat transfer is assumed to be a power function of the local temperature between the fin and the ambient which allows simulation of different convection mechanisms such as natural convection (laminar and turbulent), boiling, etc. The thermal conductivity and the surface emissivity are treated as linear functions of the local temperature between the fin and the ambient which provide a satisfactory representation of the thermal property variations of most fin materials. The thermal performance is governed by seven parameters, namely, convection–conduction parameter Nc, radiation–conduction parameter Nr, thermal conductivity parameter A, emissivity parameter B, the exponent n associated with convective heat transfer coefficient, and the two temperature ratios, θa and θs, that characterize the temperatures of convection and radiation sinks. The effect of these parameters on the temperature distribution and fin heat transfer rate are illustrated and the results interpreted in physical terms. Compared with the constant properties model, the fin heat transfer rate can be underestimated or overestimated considerably depending on the values of the governing parameters. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.20408
Effects of indoxyl sulfate on adherens junctions of endothelial cells and the underlying signaling mechanism
Authors: Peng Yu‐Sen , Lin Yen‐Tung , Chen Ying , Hung Kuan‐Yu , Wang Seu‐Mei
Published: December 2011

Uremic patients have a much higher risk of cardiovascular diseases and death. Uremic toxins are probably involved in the development of vascular endothelial dysfunction. Indoxyl sulfate (IS) is a uremic toxin that accumulates with deterioration of renal function. This study explored the effects of IS on the adherens junctions of vascular endothelial cells and revealed the underlying mechanism. Bovine pulmonary artery endothelial cells (BPAECs) were treated with IS, and the distribution of vascular endothelial cadherin (VE‐cadherin), p120‐catenin, β‐catenin, and stress fibers was examined by immunofluorescence. IS treatment resulted in disruption of intercellular contacts between BPAECs with prominent parallel‐oriented intracellular stress fiber formation. Intracellular free radical levels which measured by flow cytometry increased after IS treatment. The antioxidant, MnTMPyP, and an ERK pathway inhibitor, U0126, both significantly prevented IS‐induced disruption of intercellular contacts. Western blotting analyses demonstrated that IS‐induced phosphorylation of myosin light chain kinase (MLCK) and myosin light chains (MLC) as well as activation of extracellular‐signal‐regulated protein kinase (ERK1/ERK2). Pretreatment with MnTMPyP prevented ERK1/2 phosphorylation. U0126 prevented the IS‐induced MLCK and MLC phosphorylation. MEK‐ERK acted as the upstream regulator of the MLCK‐MLC pathway. These findings suggest that the superoxide anion‐MEK‐ERK‐MLCK‐MLC signaling mediates IS‐induced junctional dispersal of BPAECs. J. Cell. Biochem. 113: 1034–1043, 2012. © 2011 Wiley Periodicals, Inc.
Chemical transfection of dye‐conjugated microRNA precursors for microRNA functional analysis of M2 macrophages
Authors: Ng Yee Seng , Roca Hernan , Fuller David , Sud Sudha , Pienta Kenneth J.
Published: December 2011

MicroRNAs (miRNAs) are short noncoding ribonucleic acids known to affect gene expression at the translational level and there is mounting evidence that miRNAs play a role in the function of tumor‐associated macrophages (TAMs). To aid the functional analyses of miRNAs in an in‐vitro model of TAMs known as M2 macrophages, a transfection method to introduce artificial miRNA constructs or miRNA molecules into primary human monocytes is needed. Unlike differentiated macrophages or dendritic cells, undifferentiated primary human monocytes have been known to show resistance to lentiviral transduction. To circumvent this challenge, other techniques such as electroporation and chemical transfection have been used in other applications to deliver small gene constructs into human monocytes. To date, no studies have compared these two methods objectively to evaluate their suitability in the miRNA functional analysis of M2 macrophages. Of the methods tested, the electroporation of miRNA‐construct containing plasmids and the chemical transfection of miRNA precursor molecules are the most efficient approaches. The use of a silencer siRNA labeling kit (Ambion) to conjugate Cy 3 fluorescence dyes to the precursor molecules allowed the isolation of successfully transfected cells with fluorescence‐activated cell sorting. The chemical transfection of these dye‐conjugated miRNA precursors yield an efficiency of 37.5 ± 0.6% and a cell viability of 74 ± 1%. RNA purified from the isolated cells demonstrated good quality, and was fit for subsequent mRNA expression qPCR analysis. While electroporation of plasmids containing miRNA constructs yield transfection efficiencies comparable to chemical transfection of miRNA precursors, these electroporated primary monocytes seemed to have lost their potential for differentiation. Among the most common methods of transfection, the chemical transfection of dye‐conjugated miRNA precursors was determined to be the best‐suited approach for the functional analysis of M2 macrophages. J. Cell. Biochem. 113: 1714–1723, 2012. © 2012 Wiley Periodicals, Inc.
Lanthanum chloride bidirectionally influences calcification in bovine vascular smooth muscle cells
Authors: Zhao Wen‐Hua , Gou Bao‐Di , Zhang Tian‐Lan , Wang Kui
Published: December 2011

Vascular calcification (VC) is frequent prevalence in patients with chronic kidney disease (CKD) and atherosclerosis. Lanthanum carbonate is used as an orally administered phosphate‐binding agent to reduce the gastrointestinal absorption of phosphate and ameliorate VC in advanced CKD. In this study, we used bovine vascular smooth muscle cells as a model VC in vitro and studied the effects of lanthanum chloride on calcium deposition. Exposure of cells to LaCl3 at the concentration of 0.1 µM suppressed the β‐glycerophosphate‐induced alkaline phosphatase activity and calcium deposition. Furthermore, LaCl3 upregulated the β‐glycerophosphate‐suppressed expression of calcium‐sensing receptor. In contrast to the inhibitory effect of LaCl3 on calcium deposition, higher level lanthanum (50 µM) was found to promote immediately precipitation of calcium phosphate in cell culture medium. At this concentration, LaCl3 was found to induce cell apoptosis which involves caspases‐9 and ‐3. These data indicate that the promotory effect of LaCl3 on calcium deposition is likely mediated by induction of apoptosis. Our in vitro findings do suggest that, in the context of raised lanthanum, greater attention should be paid to potential toxic effects associated to the use of lanthanide‐based drugs. J. Cell. Biochem. 113: 1776–1786, 2012. © 2011 Wiley Periodicals, Inc.
Evaluation of BMP‐2 gene‐activated muscle grafts for cranial defect repair
Authors: Liu Fangjun , Porter Ryan M. , Wells James , Glatt Vaida , Pilapil Carmencita , Evans Christopher H.
Published: December 2011

Large, osseous, segmental defects heal poorly. Muscle has a propensity to form bone when exposed to an osteogenic stimulus such as that provided by transfer and expression of cDNA encoding bone morphogenetic protein‐2 (BMP‐2). The present study evaluated the ability of genetically modified, autologous muscle to heal large cranial defects in rats. Autologous grafts (8 mm × 2 mm) were punched from the biceps femoris muscle and transduced intraoperatively with recombinant adenovirus vector containing human BMP‐2 or green fluorescent protein cDNA. While the muscle biopsies were incubating with the vector, a central parietal 8 mm defect was surgically created in the calvarium of the same animal. The gene‐activated muscle graft was then implanted into the cranial defect. After 8 weeks, crania were examined radiographically, histologically, and by micro‐computed tomography and dual energy X‐ray absorptiometry. Although none of the defects were completely healed in this time, muscle grafts expressing BMP‐2 deposited more than twice as much new bone as controls. Histology confirmed the anatomical integrity of the newly formed bone, which was comparable in thickness and mineral density to the original cranial bone. This study confirms the in vivo osteogenic properties of genetically modified muscle and suggests novel strategies for healing bone. © 2011 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1095–1102, 2012
Application of stable carbon isotopes for reconstructing salt‐marsh floral zones and relative sea level, New Jersey, USA
Authors: Kemp Andrew C. , Vane Christopher H. , Horton Benjamin P. , Engelhart Simon E. , Nikitina Daria
Published: December 2011

We investigated use of δ13C in bulk organic sediment to define the botanical origin of samples preserved in coastal sediment as a means to reconstruct relative sea level in New Jersey, USA. Modern transects at three sites demonstrated that low and high salt‐marsh floral zones dominated by C4 species (Spartina alterniflora and Spartina patens) were associated with sediment δ13C values between −18.9‰ and −15.8‰ and occurred from mean tide level (MTL) to mean higher high water (MHHW). Brackish transitional settings vegetated by Phragmites australis with Iva fructescens and Typha sp. (C3 species) and freshwater upland samples (C3 species) were characterized by bulk sediment δ13C values of −27.0‰ to −22.0‰ and existed above MHHW. Parallel transects at one site suggested that intra‐site variability was not discernible. The utility of δ13C values for reconstructing relative sea level in New Jersey is limited by an inability to differentiate between brackish sediments related to sea level and freshwater upland samples. To facilitate this distinction in a 4.4 m core, we used a multi‐proxy approach (δ13C values with presence or absence of agglutinated foraminifera) to recognize indicative meanings for four sample types. Sediment with δ13C values greater than −18.9‰ was derived from a vegetated salt‐marsh and formed between MTL and MHHW. Sediment with δ13C values less than −22.0‰ and containing agglutinated foraminifera formed in a brackish transitional zone between MHHW and highest astronomical tide (HAT). This is the narrowest elevational range of the four sample types and most precise sea‐level indicator. Sediment with δ13C values less than −22.0‰ and lacking foraminifera can only constrain the upper bound of former sea level. Samples with intermediate values (−22.0‰ to −18.9‰) formed between MTL and HAT. Using these indicative meanings and radiocarbon dates, we suggest that a transition from brackish to salt‐marsh δ13C values recorded in the core took approximately 350 years (from 1800 to 1450 cal. a BP). Copyright © 2011 John Wiley & Sons, Ltd.
The dependence of radiofrequency induced pacemaker lead tip heating on the electrical conductivity of the medium at the lead tip
Authors: Langman Deborah A. , Goldberg Ira B. , Judy Jack , Paul Finn J. , Ennis Daniel B.
Published: December 2011

Radiofrequency induced pacemaker lead tip heating is one of the main reasons magnetic resonance imaging (MRI) is contraindicated for patients with pacemakers. The objective of this work was to evaluate the dependence of pacemaker lead tip heating during MRI scanning on the electrical conductivity of the medium surrounding the pacemaker lead tip. The effect of conductivity was measured using hydroxyethyl cellulose, polyacrylic acid, and saline with conductivities ranging from 0 to 3 S/m which spans the range of human tissue conductivity. The maximum lead tip heating observed in polyacrylic acid was 50.4°C at 0.28 S/m, in hydroxyethyl cellulose the maximum was 36.8°C at 0.52 S/m, and in saline the maximum was 12.5°C at 0.51 S/m. The maximum power transfer theorem was used to calculate the relative power deposited in the solution based on the characteristic impedance of the pacemaker lead and test solution impedance. The results demonstrate a strong correlation between the relative power deposited and pacemaker lead tip heating for hydroxyethyl cellulose and saline solutions. Maximum power deposition occurred when the impedance of the solution matched the pacemaker lead impedance. Pacemaker lead tip heating is dependent upon the electrical conductivity of the solution at the lead tip and should be considered when planning in vitro gel or saline experiments. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Stretchable coil arrays: Application to knee imaging under varying flexion angles
Authors: Nordmeyer‐Massner J. A. , De Zanche N. , Pruessmann K. P.
Published: December 2011

To fit high‐density receiver arrays for MRI closely around individual target anatomies, there is a need to provide a high degree of geometric adjustability with ease of handling and patient comfort. In this work, this is accomplished by the construction of a coil array that is stretchable such that it automatically conforms to a given anatomy's shape and size. Stretchability is implemented by creating the coil conductors from braided wire mounted on an elastic textile substrate. The signal‐to‐noise ratio yield of such coils is measured by MRI experiments at 3 T, and the signal‐to‐noise ratio effect of coil stretching is investigated with and without adjustment of the matching between each coil and the respective preamplifier. Four‐channel and eight‐channel arrays of stretchable receiver coils are evaluated in phantoms as well as for in vivo imaging of the human knee. Exploiting stretchability, it is demonstrated that the knee can be imaged under varying flexion angles up to 60° while maintaining closely coupled array detection, high signal‐to‐noise ratio, and uniform coverage of the entire joint. Magn Reson Med, 2012. © 2012 Wiley Periodicals, Inc.
Microscopic diffusivity compartmentation in formalin‐fixed prostate tissue
Authors: Bourne Roger M. , Kurniawan Nyoman , Cowin Gary , Stait‐Gardner Timothy , Sved Paul , Watson Geoffrey , Price William S.
Published: December 2011

MR microimaging at 16.4 T with 40‐μm isotropic voxels was used to investigate compartmentation of water diffusion in formalin‐fixed prostate tissue. Ten tissue samples (∼ 28 mm3 each) from five organs were imaged. The mean diffusivity of epithelial, stromal, and ductal/acinar compartments was estimated by two methods: (1) manual region of interest selection and (2) Gaussian fitting of voxel diffusivity histograms. For the region of interest‐method, the means of the tissue sample compartment diffusivities were significantly different (P < 0.001): 0.54 ± 0.05 μm2/ms for epithelium‐containing voxels, 0.91 ± 0.17 μm2/ms for stroma, and 2.20 ± 0.04 μm2/ms for saline‐filled ducts. The means from the histogram method were also significantly different (P < 0.001): 0.45 ± 0.08 μm2/ms for epithelium‐containing voxels, 0.83 ± 0.16 μm2/ms for stroma, 2.21 ± 0.02 μm2/ms for duct. Estimated partial volumes of epithelial, stromal, and ductal/acinar compartments in a “tissue only” subvolume of each sample were significantly different (P < 0.02) between cancer and normal tissue for all three compartments. It is concluded that the negative correlation between apparent diffusion coefficient and cancer Gleason grade observed in vivo results from an increase of partial volume of epithelial tissue and concomitant decrease of stromal tissue and ductal space. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Association of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 status with total choline concentration and tumor volume in breast cancer patients: An MRI and in vivo proton MRS study
Authors: Sah Rani G. , Sharma Uma , Parshad Rajinder , Seenu Vurthaluru , Mathur Sandeep R. , Jagannathan Naranamangalam R.
Published: December 2011

The association of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) status of breast cancer patients with total choline (tCho) concentration and tumor volume was investigated using in vivo proton magnetic resonance spectroscopy and MRI at 1.5 T. Values for tCho concentration were determined in 120 locally advanced breast cancer patients (stages IIB, IIIA, IIIB, and IIIC), 31 early breast cancer patients (stage IIA), 38 patients with benign lesions, and 37 controls. Significantly higher tCho concentration and lower tumor volume were observed in early breast cancer patients compared to locally advanced breast cancer patients (P < 0.05). tCho concentration and tumor volume did not correlate with age and menstruation. tCho cutoff values were obtained for the differentiation of malignant from benign breast tissues (2.54 mmol/kg); malignant versus normal (1.45 mmol/kg) and benign versus normal tissues (0.82 mmol/kg). Estrogen receptor negative patients showed significantly larger tumor volumes, indicating higher angiogenesis with aggressive tumor behavior. Nontriple negative and triple positive patients had a significantly higher tCho concentration compared to triple negative patients (P < 0.05), indicating complex molecular mechanism of cell proliferation and the molecular heterogeneity of breast lesions. The results indicate the potential use of integration of breast 1H magnetic resonance spectroscopy in diagnostic workup. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
In vivo chromium‐enhanced MRI of the retina
Authors: Chan Kevin C. , Fan Shu‐Juan , Zhou Iris Y. , Wu Ed X.
Published: December 2011

Chromium (Cr) has been used histologically to stabilize lipid fractions in the retina and is suggested to enhance oxidizable lipids in brain MRI. This study explored the feasibility, sensitivity, and specificity of in vivo chromium‐enhanced MRI of retinal lipids by determining its spatiotemporal profiles and toxic effect after intravitreal Cr(VI) injection to normal adult rats. One day after 3 μL Cr(VI) administration at 1–100 mM, the retina exhibited a dose‐dependent increase in T1‐weighted hyperintensity until 50 mM. Time‐dependently, significant T1‐weighted hyperintensity persisted up to 2 weeks after 10 mM Cr(VI) administration. Three‐dimensional chromium‐enhanced MRI of ex vivo normal eyes at isotropic 50‐μm resolution showed at least five alternating bands across retinal layers, with the outermost layer being the brightest. This agreed with histology indicating alternating lipid contents with the highest level in the photoreceptor layer of the outer retina. Although Cr(VI) reduction may induce oxidative stress and depolymerize microtubules, manganese‐enhanced MRI after chromium‐enhanced MRI showed a dose‐dependent effect of Cr toxicity on manganese uptake and axonal transport along the visual pathway. These results potentiated future longitudinal chromium‐enhanced MRI studies on retinal lipid metabolism upon further optimization of Cr doses with visual cell viability. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
Structure of Plasma‐Deposited Copolymer Films Prepared from Acrylic Acid and Styrene: Part I Dependence on the Duty Cycle
Authors: Fahmy Alaa , Mix Renate , Schönhals Andreas , Friedrich Jörg
Published: December 2011

Copolymers of acrylic acid and styrene (AA/S) were prepared by pulsed plasma deposition and their structures were studied in dependence on the duty cycle (DC) for a fixed composition of 1:1. As a result, low values of DC doses preserve the structure of monomers in the plasma deposited polymers while high DC leads to a higher degree of fragmentation and a loss in regular structure. Regarding plasma copolymerisation as a feasible method to finish surfaces with a definite number of functional groups it is necessary to characterize both, the chemical nature and the physical properties of the deposited layer. Therefore, a combination of different methods was employed for the characterization of thin plasma copolymer films (FTIR, dielectric spectroscopy, differential scanning calorimetry, X‐ray photoelectron spectroscopy (XPS)). Special attention was paid on the unambiguous identification of COOH groups at the surface after derivatization with trifluoroethanol by XPS and in the volume by FTIR. The glass transition temperature of the copolymer system is lower than that for the both plasma deposited homopolymers and increases with the DC in difference to plasma deposited poly(acrylic acid). The dielectric measurements showed that the plasma deposited films were not thermally stable and underwent an undesired post‐plasma chemical reaction. The results obtained by dielectric spectroscopy are discussed in detail in comparison with the data from FTIR and XPS measurements.

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Nitrogen Introduction in pp‐HMDSO Thin Films Deposited by Atmospheric Pressure Dielectric Barrier Discharge: An XPS Study
Authors: Maurau Rémy , Boscher Nicolas D. , Guillot Jérôme , Choquet Patrick
Published: December 2011

We report on the change of chemistry involved by molecular nitrogen in the deposition process of pp‐HMDSO thin films with an AP‐DBD, using HMDSO as chemical precursor. By modifying the composition of the main gas from pure argon to pure nitrogen, thin films composition varied from SiOC:H to SiOCN:H. A small amount of nitrogen favours polymer chain propagation, by consuming species responsible for chain termination and playing a role in propagation phase. Higher nitrogen content leads to more cross‐linked coatings. The use of optical emission spectroscopy together with FT‐IR and XPS is shown to be relevant to study such processes.

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Trypsin‐like proteolytic contamination of commercially available psa purified from human seminal fluid
Authors: Manning Michael L. , Kostova Maya , Williams Simon A. , Denmeade Samuel R.
Published: December 2011

BACKGROUND

Prostate‐Specific Antigen (PSA) is a serine protease whose expression is maintained in all stages of prostate cancer. A role for PSA in the pathobiology for prostate cancer has not been firmly established. Experimental studies to date support a role for PSA through mechanisms such as release or processing of growth factors and degradation of the extracellular matrix. Exposure of prostate cancer cells to exogenous PSA also results in gene expression changes. These in vitro and biochemical assays rely on the use of commercially available PSA. Contamination of these commercial preparations can significantly impact the results of these in vitro studies.

METHODS

We characterized PSA and trypsin‐like activity of PSA preparations obtained from three commercial sources: Calbiochem, Fitzgerald, and AbD Serotec. Silver stained gels were used to compare the purity of each preparation and mass spectrometry was performed to characterize contaminating proteases.

RESULTS

PSA activity varied between PSA preparations with AbD Serotec PSA having highest degree of activity. Significant trypsin‐like activity, which was inhibited by aprotinin, was observed in PSA preparations from Calbiochem and Fitzgerald, but not AbD Serotec. These former two PSA preparations also contained the greatest degree of non‐PSA contaminants by silver stain and mass spectrometry.

CONCLUSIONS

Commercially available preparations of PSA contain contaminating proteins, including trypsin‐like protease activity, that could potentially complicate the interpretation of results obtained from in vitro studies assessing PSA proteolysis of potential protein substrates and effects of PSA on gene expression. Prostate 72:1233–1238, 2012. © 2011 Wiley Periodicals, Inc.
Effects of Short Vacations, Vacation Activities and Experiences on Employee Health and Well‐Being
Authors: de Bloom Jessica , Geurts Sabine A. E. , Kompier Michiel A. J.
Published: December 2011

It was investigated (1) whether employee health and well‐being (H&W) improve during short vacations (4–5 days), (2) how long this improvement lasts after returning home and resuming work and (3) to what extent vacation activities and experiences explain health improvements during and after short vacations.

Eighty workers reported their H&W 2 weeks before vacation (Pre), during vacation (Inter), on the day of return (Post 1) and on the third and 10th day after returning home (Post 2 and Post 3, respectively).

The results showed improvements in H&W during short vacations (d = 0.62), although this effect faded out rather quickly. Partial correlations and regression analyses showed that employees reported higher H&W during vacation, the more relaxed and psychologically detached they felt, the more time they spent on conversations with the partner, the more pleasure they derived from their vacation activities and the lower the number of negative incidents during vacation. Experiences of relaxation and detachment from work positively influenced H&W even after returning home. Working during vacation negatively influenced H&W after vacation.

In conclusion, short vacations are an effective, although not very long lasting, ‘cure’ to improve employees' H&W. Copyright © 2011 John Wiley & Sons, Ltd.
Corporate governance and environmental performance: is there really a link?
Authors: Walls Judith L. , Berrone Pascual , Phan Phillip H.
Published: December 2011

Corporate governance scholars are increasingly interested in firms' social and environmental performance. Empirical research in this area, however, has moved forward in an uncoordinated fashion, producing fragmented and contradictory results. Our paper seeks to address this situation by adopting a fact‐based research approach that comprehensively explores the link between corporate governance and environmental performance. Specifically, we aim to understand how the relationships between and among the firms' owners, managers, and boards of directors influence environmental performance. We are particularly interested in understanding the interactions among these three key sets of actors. In the end, we offer some observations about governance practices and discuss the implications for theory. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of mirtazapine on sleep disturbance under neuropathic pain‐like state
Authors: Enomoto Tatsuya , Yamashita Akira , Torigoe Kazuhiro , Horiuchi Hiroshi , Hirayama Shigeto , Nakahara Kae , Yanase Makoto , Sakai Hiroyasu , Ikegami Daigo , Nagase Hiroshi , Suzuki Tsutomu , Iseki Masako , Inada Eiichi , Narita Minoru
Published: December 2011

Sleep disturbance has been reported to be one of the most frequent symptoms in patients suffered from severe pain. Benzodiazepines are effective and reduce anxiety in the hours after use, but the induced sleep tends to be less than ideal in quality, with increased Stages I–II and reduces Stages III–IV sleep. In the present study, we investigated sleep disturbance under a neuropathic pain‐like state in mice using electroencephalogram (EEG)/electromyogram (EMG). In a model of neuropathic pain, sciatic nerve ligation caused a marked decrease in the latency of paw withdrawal in response to a thermal stimulus only on the ipsilateral side. Under this condition, sciatic nerve‐ligated animals showed a statistically significant increase in wakefulness and a decrease in non‐rapid eye movement (NREM) sleep during the light phase. Mirtazapine (MTZ) is an antidepressant, which is considered to enhance noradrenergic and serotonergic neurotransmission via antagonistic action at central α2‐adrenergic autoreceptors and heteroreceptors. In the present binding study, MTZ showed higher affinity for histamine H1 and serotonin 5‐HT2A/2C receptors than other receptors, including α2‐adrenergic receptor, in the mouse brain tissue. The thermal hyperalgesia and sleep disturbance following nerve ligation were almost completely alleviated by MTZ. These findings suggest that MTZ may improve the quality of sleep as well as control pain in patients with neuropathic pain mainly through histamine H1‐ and serotonin 5‐HT2‐receptor antagonistic actions. Synapse, 2012. © 2011 Wiley Periodicals, Inc.
Synthesis, Structure, and Magnetic Properties of a Dinuclear Antiferromagnetically Coupled Cobalt Complex
Authors: Wu Da‐Yu , Huang Wei , Wang Laiguo , Wu Genhua
Published: December 2011

A new dinuclear cobalt(II) compound,[(TPA*)CoII(DHBQ2–)CoII(TPA*)]2+ (12+) {TPA* =tris[(3, 5‐dimethyl‐pyrazol‐l‐yl)methyl] amine, DHBQ = deprotonated 2, 5‐dihydroxy‐1, 4‐benzoquinone}, was prepared and structurally and magnetically characterized. X‐ray crystallography revealed the centrosymmetric dinuclear divalent cobalt ions bridged by DHBQ2– unit. The cobalt ions in the title compound have a distorted octahedral arrangement by coordination with four nitrogens of a TPA* and two oxygens of a bridging DHBQ unit. Due to the interdimer offset face‐to‐face π–π stacking in the crystallographic ac plane, the complex shows extended 2D supramolecular structure. Magnetic experiments showed the cobalt‐based dinuclear compound exhibits antiferromagnetic interactions with g = 2.35 and J/kB = –2.76 K, respectively.
Generation of inhomogeneous plane shear acoustic modes by laser-induced thermoelastic gratings at the interface of transparent and opaque solids
Authors: Kouyate Mansour , Pezeril Thomas , Mounier Denis , Gusev Vitalyi
Published: December 2011

The detailed theoretical description of how picosecond plane shear acoustic fronts can be excited by ultrafast lasers at the interface of two isotropic media, a transparent medium and an opaque medium, is presented. The processes leading to the emission of inhomogeneous plane bulk shear acoustic modes from the interaction at the interface of plane inhomogeneous compression/dilatation modes thermoelastically generated by laser interference gratings are analyzed. The theory describes the basic features of the spectral transformation function of the laser light conversion into shear modes and predicts an interval of frequencies where it is possible to achieve the emission into the transparent medium of propagating shear inhomogeneous modes only, while the compression/dilatation inhomogeneous modes will be evanescent and will be localized at the interface. The guidelines for optimal choice of the materials, with the goal of improving the amplitude of the photoexcited picosecond shear acoustic fronts are proposed. All-optical monitoring, i.e., excitation and detection, by fs-ps laser pulses of picosecond plane inhomogeneous shear acoustic fronts propagating in thin films and substrates can be applied for the noncontact determination of shear rigidity of materials.
Scanning properties of a resonant fiber-optic piezoelectric scanner
Authors: Li Zhi , Yang Zhe , Fu Ling
Published: December 2011

We develop a resonant fiber-optic scanner using four piezoelectric elements arranged as a square tube, which is efficient to manufacture and drive. Using coupled-field model based on finite element method, scanning properties of the scanner, including vibration mode, resonant frequency, and scanning range, are numerically studied. We also physically measure the effects of geometry sizes and drive signals on the scanning properties, thus providing a foundation for general purpose designs. A scanner adopted in a prototype of imaging system, with a diameter of ∼2 mm and driven by a voltage of 10 V (peak to peak), demonstrates the scanning performance by obtaining an image of resolution target bars. The proposed fiber-optic scanner can be applied to micro-endoscopy that requires two-dimensional scanning of fibers.
Long-range interactions between like homonuclear alkali metal diatoms
Authors: Byrd Jason N. , Côté Robin , Montgomery John A.
Published: December 2011

Long-range electrostatic and van der Waals coefficients up to terms of order R−8 have been evaluated by the sum over states method using ab initio and time-dependent density functional theory. We employ several widely used density functionals and systematically investigate the convergence of the calculated results with basis set size. Static electric moments and polarizabilities up to octopole order are also calculated. We present values for Li2 through K2 which are in good agreement with existing values, in addition to new results for Rb2 and Cs2. Interaction potential curves calculated from these results are shown to agree well with high level ab initio theory. Preliminary results are reported that demonstrate the applicability of the method to larger alkali clusters.
Fast switching of magnetization in the ferromagnetic semiconductor (Ga,Mn)(As,P) using nonequilibrium phonon pulses
Authors: Casiraghi A. , Walker P. , Akimov A. V. , Edmonds K. W. , Rushforth A. W. , De Ranieri E. , Campion R. P. , Gallagher B. L. , Kent A. J.
Published: December 2011

We use short acoustic pulses to induce a fast irreversible switching of the magnetization orientation in a layer of (Ga,Mn)(As,P). The pulses are generated by femtosecond optical excitation of a metal transducer film and travel ballistically through the sample. We show that the switching is triggered by incoherent acoustic phonons, occurs through domain-related processes, and is concluded in ∼35 ns. We suggest that the mechanism behind the switching involves the holes in the material being heated due to their coupling to the phonons.
Microfabricated continuous cubic phase plate induced Airy beams for optical manipulation with high power efficiency
Authors: Cao Rui , Yang Yong , Wang Jingang , Bu Jing , Wang Mingwei , Yuan X.-C.
Published: December 2011

We studied and demonstrated optical trapping capabilities of an Airy beam generated with a cubic phase plate incorporated into a conventional optical tweezer system. The power efficiency and damage threshold of the cubic phase plate were found to be much higher when spatial light modulators were employed in beam generation.
Evolution of sheet resistance of thin Ni film deposited on porous anodic alumina substrate
Authors: Song Aree , Sung Kim Chul , Kouh Taejoon
Published: December 2011

We have investigated the evolution of sheet resistance of thin nickel films, thermally evaporated on porous alumina substrates, based on in situ electron transport measurement. By comparing the porous films, having various surface area fractions, to the uniform film, following the scaling law in metal-insulator transition, we have been able to describe the growth and the resulting thickness-dependent sheet resistance of the porous film in light of the two-dimensional percolation model. The underlying pore array strongly affects the appearance of the film conductance, and the study suggests the possibility of modulating the electron transport characteristics with the constrained surface geometry.
Intense terahertz emission from atomic cluster plasma produced by intense femtosecond laser pulses
Authors: Jahangiri Fazel , Hashida Masaki , Nagashima Takeshi , Tokita Shigeki , Hangyo Masanori , Sakabe Shuji
Published: December 2011

Terahertz (THz) emission from argon cluster plasma, generated by intense femtosecond laser pulses in the energy range of 10–70 mJ, has been investigated. THz polarization, energy dependence, and angular distribution were measured to provide an initial discussion on the mechanisms of THz emission. THz pulses of much higher energy were generated from argon clusters than from argon gas, which indicates that plasma produced from atomic clusters holds considerable promise as an intense THz source.
GaSb nanowire single-hole transistor
Authors: Ganjipour Bahram , Nilsson Henrik A. , Mattias Borg B. , Wernersson Lars-Erik , Samuelson Lars , Xu H. Q. , Thelander Claes
Published: December 2011

We present an experimental study of single hole transistors (SHTs) made from p-type GaSb nanowires. Closely spaced source-drain electrodes are fabricated onto GaSb nanowires to define a SHT within a GaSb nanowire. Room temperature back-gate transfer characteristics show typical hole transport behavior. The fabricated devices are characterized by transport measurements at 1.5 K, where periodic conductance oscillations due to Coulomb blockade are observed and a charging energy of 5 meV is determined.
Vertebrate-like regeneration in the invertebrate chordate amphioxus
Authors: Somorjai Ildikó M. L. , Somorjai Rajmund L. , Garcia-Fernàndez Jordi , Escrivà Hector
Published: December 2011

An important question in biology is why some animals are able to regenerate, whereas others are not. The basal chordate amphioxus is uniquely positioned to address the evolution of regeneration. We report here the high regeneration potential of the European amphioxus
Branchiostoma lanceolatum
. Adults regenerate both anterior and posterior structures, including neural tube, notochord, fin, and muscle. Development of a classifier based on tail regeneration profiles predicts the assignment of young and old adults to their own class with >94% accuracy. The process involves loss of differentiated characteristics, formation of an
msx
-expressing blastema, and neurogenesis. Moreover, regeneration is linked to the activation of satellite-like Pax3/7 progenitor cells, the extent of which declines with size and age. Our results provide a framework for understanding the evolution and diversity of regeneration mechanisms in vertebrates.
Revealing conformational substates of lipidated N-Ras protein by pressure modulation
Authors: Kapoor Shobhna , Triola Gemma , Vetter Ingrid R. , Erlkamp Mirko , Waldmann Herbert , Winter Roland
Published: December 2011

Regulation of protein function is often linked to a conformational switch triggered by chemical or physical signals. To evaluate such conformational changes and to elucidate the underlying molecular mechanisms of subsequent protein function, experimental identification of conformational substates and characterization of conformational equilibria are mandatory. We apply pressure modulation in combination with FTIR spectroscopy to reveal equilibria between spectroscopically resolved substates of the lipidated signaling protein N-Ras. Pressure has the advantage that its thermodynamic conjugate is volume, a parameter that is directly related to structure. The conformational dynamics of N-Ras in its different nucleotide binding states in the absence and presence of a model biomembrane was probed by pressure perturbation. We show that not only nucleotide binding but also the presence of the membrane has a drastic effect on the conformational dynamics and selection of conformational substates of the protein, and a new substate appearing upon membrane binding could be uncovered. Population of this new substate is accompanied by structural reorientations of the G domain, as also indicated by complementary ATR-FTIR and IRRAS measurements. These findings thus illustrate that the membrane controls signaling conformations by acting as an effective interaction partner, which has consequences for the G-domain orientation of membrane-associated N-Ras, which in turn is known to be critical for its effector and modulator interactions. Finally, these results provide insights into the influence of pressure on Ras-controlled signaling events in organisms living under extreme environmental conditions as they are encountered in the deep sea where pressures reach the kbar range.
Genome and physiology of a model Epsilonproteobacterium responsible for sulfide detoxification in marine oxygen depletion zones
Authors: Grote Jana , Schott Thomas , Bruckner Christian G. , Glöckner Frank Oliver , Jost Günter , Teeling Hanno , Labrenz Matthias , Jürgens Klaus
Published: December 2011

Eutrophication and global climate change lead to expansion of hypoxia in the ocean, often accompanied by the production of hydrogen sulfide, which is toxic to higher organisms. Chemoautotrophic bacteria are thought to buffer against increased sulfide concentrations by oxidizing hydrogen sulfide before its diffusion to oxygenated surface waters. Model organisms from such environments have not been readily available, which has contributed to a poor understanding of these microbes. We present here a detailed study of “
Sulfurimonas gotlandica
” str. GD1, an Epsilonproteobacterium isolated from the Baltic Sea oxic-anoxic interface, where it plays a key role in nitrogen and sulfur cycling. Whole-genome analysis and laboratory experiments revealed a high metabolic flexibility, suggesting a considerable capacity for adaptation to variable redox conditions.
S. gotlandica
str. GD1 was shown to grow chemolithoautotrophically by coupling denitrification with oxidation of reduced sulfur compounds and dark CO
2
fixation. Metabolic versatility was further suggested by the use of a range of different electron donors and acceptors and organic carbon sources. The number of genes involved in signal transduction and metabolic pathways exceeds those of other
Epsilonproteobacteria
. Oxygen tolerance and environmental-sensing systems combined with chemotactic responses enable this organism to thrive successfully in marine oxygen-depletion zones. We propose that
S. gotlandica
str. GD1 will serve as a model organism in investigations that will lead to a better understanding how members of the
Epsilonproteobacteria
are able to cope with water column anoxia and the role these microorganisms play in the detoxification of sulfidic waters.
Lupus-associated causal mutation in neutrophil cytosolic factor 2 (NCF2) brings unique insights to the structure and function of NADPH oxidase
Authors: Jacob Chaim O. , Eisenstein Miriam , Dinauer Mary C. , Ming Wenyu , Liu Qiang , John Sutha , Quismorio Francesco P. , Reiff Andreas , Myones Barry L. , Kaufman Kenneth M. , McCurdy Deborah , Harley John B. , Silverman Earl , Kimberly Robert P. , Vyse Timothy J. , Gaffney Patrick M. , Moser Kathy L. , Klein-Gitelman Marisa , Wagner-Weiner Linda , Langefeld Carl D. , Armstrong Don L. , Zidovetzki Raphael
Published: December 2011

Systemic lupus erythematosus (SLE), the prototypic systemic autoimmune disease, is a debilitating multisystem autoimmune disorder characterized by chronic inflammation and extensive immune dysregulation in multiple organ systems, resulting in significant morbidity and mortality. Here, we present a multidisciplinary approach resulting in the identification of neutrophil cytosolic factor 2 (
NCF2
) as an important risk factor for SLE and the detailed characterization of its causal variant. We show that
NCF2
is strongly associated with increased SLE risk in two independent populations: childhood-onset SLE and adult-onset SLE. The association between
NCF2
and SLE can be attributed to a single nonsynonymous coding mutation in exon 12, the effect of which is the substitution of histidine-389 with glutamine (H389Q) in the PB1 domain of the NCF2 protein, with glutamine being the risk allele. Computational modeling suggests that the NCF2 H389Q mutation reduces the binding efficiency of NCF2 with the guanine nucleotide exchange factor Vav1. The model predicts that NCF2/H389 residue interacts with Vav1 residues E509, N510, E556, and G559 in the ZF domain of Vav1. Furthermore, replacing H389 with Q results in 1.5 kcal/mol weaker binding. To examine the effect of the NCF2 H389Q mutation on NADPH oxidase function, site-specific mutations at the 389 position in NCF2 were tested. Results show that an H389Q mutation causes a twofold decrease in reactive oxygen species production induced by the activation of the Vav-dependent Fcγ receptor-elicited NADPH oxidase activity. Our study completes the chain of evidence from genetic association to specific molecular function.
Human cytomegalovirus activation of ERK and myeloid cell leukemia-1 protein correlates with survival of latently infected cells
Authors: Reeves Matthew B. , Breidenstein Abagail , Compton Teresa
Published: December 2011

The ability of human CMV (HCMV) to enter and establish a latent infection in myeloid cells is crucial for survival and transmission in the human population. Initial pathogen binding and entry triggers a number of antiviral responses, including the activation of proapoptotic cell death pathways, which must be countered during latency establishment. However, mechanisms responsible for a prosurvival state in myeloid cells upon latent HCMV infection remain completely undefined. We hypothesized that the cellular antiapoptotic machinery must be initially activated by HCMV to promote early survival events upon entry. Here we show that HCMV transiently protects nonpermissive myeloid cells from chemical and virus entry induced cell death by up-regulating a key myeloid cell survival gene, myeloid cell leukemia (MCL)-1 protein. The induction of MCL-1 expression was independent of viral gene expression but dependent on activation of the ERK–MAPK pathway by viral glycoprotein B. Inhibition of ERK-MAPK signaling, inhibition of HCMV fusion, antibody-mediated neutralization of glycoprotein B signaling or expression of a shRNA against MCL-1 all correlated with increased cell death in response to virus infection or chemical stimulation. Finally we show that activation of ERK–MAPK signaling impacts on long-term latency and reactivation in hematopoietic cells. Thus, HCMV primes myeloid cells for from the initial virus-cell encounter. Given the importance of ERK and MCL-1 for myeloid cell survival, the successful establishment of HCMV latency in myeloid progenitors begins at the point of virus entry.