bluuebunny/crossref_metadata_2025 huggingface dataset:
Pollution, toxicity, and ecological risk of heavy metals in surface river sediments of a large basin undergoing rapid economic development
Authors: Tang Wenzhong , Zhang Chao , Zhao Yu , Shan Baoqing , Song Zhixin
Published: October 2016

A comprehensive and detailed investigation of heavy metal pollution, toxicity, and ecological risk assessment was conducted for the surface river sediments of the Haihe Basin in China based on 220 sampling sites selected in 2013. The average concentrations of Cr, Cu, Ni, Pb, and Zn in the sediments were 129 mg/kg, 63.4 mg/kg, 36.6 mg/kg, 50.0 mg/kg, and 202 mg/kg, respectively. As indicated by the geoaccumulation and pollution load indices, most surface river sediments of the Haihe Basin were contaminated with the investigated metals, especially in the junction region of the Zi Ya He and Hei Long Gang watersheds. The 5 heavy metals in the sediments all had anthropogenic sources, and the enrichment degrees followed the order Cu > Pb > Zn > Cr > Ni, with mean enrichment factors of 3.27, 2.77, 2.58, 1.81, and 1.44, respectively. According to the mean index of comprehensive potential ecological risk (38.9), the studied sediments of the Haihe Basin showed low potential ecological risk, but the sediments were potentially biologically toxic based on the mean probable effect concentration quotient (0.547), which may be the result of speciation of the 5 metals in the sediments. The results indicate that heavy metal pollution should be considered during the development of ecological restoration strategies in the Haihe Basin. Environ Toxicol Chem 2017;36:1149–1155. © 2016 SETAC
Check‐hybrid GLDPC codes: Systematic elimination of trapping sets and guaranteed error correction capability
Authors: Ravanmehr Vida , Khatami Mehrdad , Declercq David , Vasic Bane
Published: October 2016

In this paper, we propose a new approach to construct a class of check‐hybrid generalized low‐density parity‐check (CH‐GLDPC) codes, which are free of small trapping sets. The approach is based on converting some selected check nodes involving a trapping set into super checks corresponding to a 2‐error‐correcting component code. Specifically, we follow 2 main purposes to construct the check‐hybrid codes; first, on the basis of the knowledge of trapping sets of an LDPC code, single parity checks are replaced by super checks to disable the trapping sets. We show that by converting specified single check nodes, denoted as critical checks, to super checks in a trapping set, the parallel bit flipping decoder corrects the errors on a trapping set. The second purpose is to minimize the rate loss through finding the minimum number of such critical checks. We also present an algorithm to find critical checks in a trapping set of a column‐weight 3 LDPC code of girth 8 and then provide upper bounds on the minimum number of such critical checks such that the decoder corrects all error patterns on elementary trapping sets. Guaranteed error correction capability of the CH‐GLDPC codes is also studied. We show that a CH‐GLDPC code in which each variable node is connected to 2 super checks corresponding to a 2‐error‐correcting component code corrects up to 5 errors. The results are also extended to column‐weight 4 LDPC codes of girth 6. Finally, we investigate eliminating of trapping sets of a column‐weight 3 LDPC code of girth 8 using the Gallager B decoding algorithm.
Continuous fiber‐reinforced thermoplastic composites: influence of processing on fire retardant properties
Authors: Lin Qing , Ferriol Michel , Cochez Marianne , Vahabi Henri , Vagner Christelle
Published: October 2016

Fiber‐reinforced thermoplastic composite materials can find numerous applications in the transportation sector and replace thermoset composites. However, they have to comply with strict standards, particularly with those concerning their fire behavior. In this frame, composites based on an acrylic resin Elium® (Arkema), a woven fiberglass, (taffetas tissue Chomarat G‐Weave 600 P/A) and Exolit OP930 (Clariant) as fire retardant were prepared by using three processes. The thermal stability and fire behavior were studied by means of thermogravimetric analysis and cone calorimetry. The obtained results allowed to highlight the drawbacks of each processing method and to select the most appropriate. The improvement of the fire behavior by combining post‐curing of the composites, addition of a cross‐linking agent, and addition of aluminum trihydroxide was also investigated. Copyright © 2016 John Wiley & Sons, Ltd.
Multi‐scale experimental investigations of the thermal degradation of pine needles
Authors: Fateh T. , Richard F. , Zaida J. , Rogaume T. , Joseph P.
Published: October 2016

In this work, the thermal degradation of pine needles (from a Mediterranean species) was studied using a thermogravimetric analysis and cone calorimeter that were coupled to Fourier transform infrared spectrometer. The thermogravimetric analyses were carried out at four heating rates, in both air and nitrogen atmospheres. The evolution of gaseous components, mass loss and mass loss rate were recorded as a function of time and temperature. In order to account for the observed behaviours of the materials, we have also proposed a mechanism for the thermal degradation of pine needles, by primarily analysing the evolutions of both mass loss rate and gaseous components under nitrogen and air atmospheres. The kinetic parameters were subsequently estimated by using a genetic algorithm method. The cone calorimetric measurements were mainly conducted with a view to investigating the influence of thermal transfer processes, occurring in a porous bed of pine needles with regard to its thermal degradation. The experiments were conducted at five external heat fluxes under a well‐ventilated atmosphere. Measurements consisted of the mass loss, mass loss rate and the amount of gaseous emissions. The main gases emitted during the thermal degradation and the combustion of the pine needles were found to be CH4, CO, CO2, NO and water vapour. In addition, the evolution of the temperature was measured by using a set of five thermocouples, placed in a vertical position at the centreline of the sample. The results obtained showed that the bed of pine needles behaved as a thermally thick fuel. On the contrary, at higher external heat fluxes, the sample behaved as a thermally thin sample. Copyright © 2016 John Wiley & Sons, Ltd.
The Role of Medical Expenditure Risk in Portfolio Allocation Decisions
Authors: Ayyagari Padmaja , He Daifeng
Published: October 2016

Economic theory suggests that medical spending risk affects the extent to which households are willing to accept financial risk, and consequently their investment portfolios. In this study, we focus on the elderly for whom medical spending represents a substantial risk. We exploit the exogenous reduction in prescription drug spending risk because of the introduction of Medicare Part D in the U.S. in 2006 to identify the causal effect of medical spending risk on portfolio choice. Consistent with theory, we find that Medicare‐eligible persons increased risky investment after the introduction of prescription drug coverage, relative to a younger, ineligible cohort. Copyright © 2016 John Wiley & Sons, Ltd.
Earlier and more specific detection of persistent neck disease with diffusion‐weighted MRI versus subsequent PET/CT after definitive chemoradiation for oropharyngeal squamous cell carcinoma
Authors: Yu Yao , Mabray Marc , Silveira William , Shen Peter Y. , Ryan William R. , Uzelac Alina , Yom Sue S.
Published: October 2016

Background

The purpose of this study was to test if diffusion‐weighted imaging (DWI) identified persistent neck disease after chemoradiotherapy (CRT) for oropharyngeal cancer earlier and as accurately as subsequent positron emission tomography (PET)/CT.

Methods

We performed a review of patients with oropharyngeal cancer treated with definitive CRT who underwent DWI and PET/CT at a median of 8 and 14 weeks posttreatment. Imaging characteristics were correlated with pathologically proven neck failure.

Results

Forty‐one patients and 58 hemi‐necks were analyzed. With a median follow‐up of 120 weeks, 4 neck failures were identified. The apparent diffusion coefficient (ADC) of lymph node failures was lower (1220 vs 1910 μm2/s; p = .003) than non‐failures. Using an ADC threshold of 1500 μm2/s, the sensitivity, specificity, and positive and negative predictive values (PPV; NPV) were 100% (4/4), 92% (46/50), 50% (4/8), and 100% (46/46) for DWI, respectively, and 100% (3/3), 71% (22/31), 25% (3/12), and 100% (22/22) for PET/CT, respectively.

Conclusion

Earlier DWI produced similar sensitivity and better specificity in identifying persistent neck disease as 3‐month PET/CT. © 2016 Wiley Periodicals, Inc. Head Neck 39: 432–438, 2017
Financial Cycle, Business Cycle and Monetary Policy: Evidence from Four Major Economies
Authors: Ma Yong , Zhang Jinglan
Published: October 2016

Economists used to think that financial factors are not important in the business cycle, but the 2008 global financial crisis has made it apparent that financial cycle plays a much larger role in macroeconomic dynamics than anticipated. Against this background, economists endeavor to introduce financial factors into macroeconomic models. In this paper, we incorporate financial cycle into a four‐equation model to study the linkages and interactions between financial cycle, business cycle and monetary policy. The results suggest that financial cycle plays a significant role in the business cycle, and that financial cycle shock has become a main driving force for macroeconomic fluctuations, especially during times of financial instability. In addition, by comparing the performance of the finance‐augmented Taylor rule with that of the conventional Taylor rule, we find that both the financial system and the real economy will be better stabilized under the finance‐augmented Taylor rule. This result adds new evidence to the argument that monetary policy has an important role in safeguarding the financial system and that financial stability should be adopted as a target for monetary policy. Copyright © 2016 John Wiley & Sons, Ltd.
Comparing fixed‐amount and progressive‐amount DRO Schedules for tic suppression in youth with chronic tic disorders
Authors: Capriotti Matthew R. , Turkel Jennifer E. , Johnson Rachel A. , Espil Flint M. , Woods Douglas W.
Published: October 2016

Chronic tic disorders (CTDs) involve motor and/or vocal tics that often cause substantial distress and impairment. Differential reinforcement of other behavior (DRO) schedules of reinforcement produce robust, but incomplete, reductions in tic frequency in youth with CTDs; however, a more robust reduction may be needed to affect durable clinical change. Standard, fixed‐amount DRO schedules have not commonly yielded such reductions, so we evaluated a novel, progressive‐amount DRO schedule, based on its ability to facilitate sustained abstinence from functionally similar behaviors. Five youth with CTDs were exposed to periods of baseline, fixed‐amount DRO (DRO‐F), and progressive‐amount DRO (DRO‐P). Both DRO schedules produced decreases in tic rate and increases in intertic interval duration, but no systematic differences were seen between the two schedules on any dimension of tic occurrence. The DRO‐F schedule was generally preferred to the DRO‐P schedule. Possible procedural improvements and other future directions are discussed.
Novel silk protein barrier membranes for guided bone regeneration
Authors: Smeets Ralf , Knabe Christine , Kolk Andreas , Rheinnecker Michael , Gröbe Alexander , Heiland Max , Zehbe Rolf , Sachse Manuela , Große‐Siestrup Christian , Wöltje Michael , Hanken Henning
Published: October 2016

This study assesses the biocompatibility of novel silk protein membranes with and without modification, and evaluates their effect on facilitating bone formation and defect repair in guided bone regeneration. Two calvarian bone defects 12 mm in diameter were created in each of a total of 38 rabbits. Four different types of membranes, (silk‐, hydroxyapatite‐modified silk‐, β‐TCP‐modified silk‐ and commonly clinically used collagen‐membranes) were implanted to cover one of the two defects in each animal. Histologic analysis did not show any adverse tissue reactions in any of the defect sites indicating good biocompatibility of all silk protein membranes. Histomorphometric and histologic evaluation revealed that collagen and β‐TCP modified silk membranes supported bone formation (collagen: bone area fraction p = 0.025; significant; β‐TCP modified silk membranes bone area fraction: p = 0.24, not significant), guided bone regeneration and defect bridging. The bone, which had formed in defects covered by β‐TCP modified silk membranes, displayed a more advanced stage of bone tissue maturation with restoration of the original calvarial bone microarchitecture when compared to the bone which had formed in defects, for which any of the other test membranes were used. Micro‐CT analysis did not reveal any differences in the amount of bone formation between defects with and without membranes. In contrast to the collagen membranes, β‐TCP modified silk membranes were visible in all cases and may therefore be advantageous for further supporting bone formation beyond 10 weeks and preventing soft tissue ingrowth from the periphery. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2603–2611, 2017.
Development and Validation of a Novel Laboratory-Specific Correction Equation for Total Serum Calcium and Its Association With Mortality Among Hemodialysis Patients
Authors: Obi Yoshitsugu , Nguyen Danh V , Streja Elani , Rivara Matthew B , Rhee Connie M , Lau Wei Ling , Chen Yanjun , Kovesdy Csaba P , Mehrotra Rajnish , Kalantar-Zadeh Kamyar
Published: October 2016

Conventional albumin-corrected calcium is inaccurate in predicting ionized calcium, and hidden hypercalcemia, characterized as high ionized calcium with normal total calcium, is associated with higher mortality in hemodialysis patients. By using a national cohort of hemodialysis patients in the Unites States, a novel laboratory-specific prediction equation composed of total calcium, albumin, and phosphorus was derived from 242 patients in the South Atlantic division (adjusted R2 = 0.80 versus 0.71 for the conventional equation) and then validated among 566 patients in the other divisions (adjusted R2 = 0.79 versus 0.68 for the conventional equation). Compared with the conventional equation, the novel equation showed a greater correlation with intact parathyroid hormone. Its relative performance against the conventional equation was consistent across subgroups based on medications related to calcium metabolism. The novel equation also had a higher sensitivity (57% versus 34%) and an equivalent specificity (99% versus 100%) against ionized hypercalcemia at a cut-off value of 10.2 mg/dL. Sensitivity and specificity at 9.4 mg/dL was 94% and 76% (versus 87% and 82% for the conventional equation), respectively. A survival analysis in 87,779 incident hemodialysis patients showed that among patients who were categorized as having a high-normal calcium status (ie, >9.4 to 10.2 mg/dL) by the conventional equation, there appeared a trend toward higher adjusted mortality risk across higher calcium status defined according to the novel equation. Meanwhile, the mortality risk was consistent across calcium strata defined according to the conventional equation within the categories defined by the novel equation. In conclusion, in comparison to the conventional equation, a novel laboratory-specific correction equation derived for correction of total calcium performs significantly better in ascertaining hidden hypercalcemia in hemodialysis patients, and aids in identifying patients at higher risk for mortality. © 2016 American Society for Bone and Mineral Research.
A Novel High Efficient Catalyst AgBr/CaMoO4 for the Reduction of p‐Nitrophenol
Authors: Wang Xiaomin , Song Jimei , Gao Rui , Yang Jie
Published: October 2016

A new composite catalyst AgBr/CaMoO4
was successfully fabricated by loading AgBr nanoparticles on CaMoO4
support via a convenient precipitation/deposition method, without any controlling agent and template. The microstructure, chemical composition, and morphologies of the AgBr/CaMoO4
were characterized by X‐ray diffraction, Fourier transform infrared, X‐ray photoelectron spectroscopy, and scanning electron microscopy. A series of comparative experiments showed that the composite AgBr/CaMoO4
exhibits higher catalytic activity than pure AgBr or CaMoO4
for the reduction of p‐nitrophenol (4‐NP). Moreover, the AgBr content greatly impacted the catalytic activity of composite AgBr/CaMoO4
. The conversion rate of 4‐NP with AgBr/CaMoO4
‐5% as catalyst could reach 100% within only 4 min, which might be attributed to more number of available active sites from the highly dispersed AgBr nanoparticles on the surface of CaMoO4
microspheres. In addition, the composite catalyst AgBr/CaMoO4
displayed a good structural and cycling stability. The present study might provide a new strategy to design composite materials with excellent catalytic performance.
Essential Role of CFTR in PKA‐Dependent Phosphorylation, Alkalinization, and Hyperpolarization During Human Sperm Capacitation
Authors: Puga Molina Lis C. , Pinto Nicolás A. , Torres Rodríguez Paulina , Romarowski Ana , Vicens Sanchez Alberto , Visconti Pablo E. , Darszon Alberto , Treviño Claudia L. , Buffone Mariano G.
Published: October 2016

Mammalian sperm require to spend a limited period of time in the female reproductive tract to become competent to fertilize in a process called capacitation. It is well established that HCO3− is essential for capacitation because it activates the atypical soluble adenylate cyclase ADCY10 leading to cAMP production, and promotes alkalinization of cytoplasm, and membrane hyperpolarization. However, how HCO3− is transported into the sperm is not well understood. There is evidence that CFTR activity is involved in the human sperm capacitation but how this channel is integrated in the complex signaling cascades associated with this process remains largely unknown. In the present work, we have analyzed the extent to which CFTR regulates different events in human sperm capacitation. We observed that inhibition of CFTR affects HCO3−‐entrance dependent events resulting in lower PKA activity. CFTR inhibition also affected cAMP/PKA‐downstream events such as the increase in tyrosine phosphorylation, hyperactivated motility, and acrosome reaction. In addition, we demonstrated for the first time, that CFTR and PKA activity are essential for the regulation of intracellular pH, and membrane potential in human sperm. Addition of permeable cAMP partially recovered all the PKA‐dependent events altered in the presence of inh‐172 which is consistent with a role of CFTR upstream of PKA activation. J. Cell. Physiol. 232: 1404–1414, 2017. © 2016 Wiley Periodicals, Inc.
Life cycle assessment of solar‐driven oxidation as a polishing step of secondary‐treated urban effluents
Authors: Ioannou‐Ttofa Lida , Foteinis Spyros , Chatzisymeon Efthalia , Michael‐Kordatou Irene , Fatta‐Kassinos Despo
Published: October 2016

BACKGROUND

In this work, the life cycle assessment (LCA) methodology is utilized to estimate the environmental footprint of solar Fenton oxidation at pilot scale used as a polishing step of secondary‐treated urban effluents. All inputs (e.g. natural resources, raw materials, etc.) and outputs (e.g. emissions, etc.) of the process were quantitatively defined and/or estimated. The system under study includes raw materials, energy, land use, chemicals, local transportation needs, and air‐/waterborne emissions.

RESULTS

The main environmental hotspots of this system were identified (i.e. energy consumption and use of chemicals). The environmental sustainability of this technology was found to be high, since its environmental footprint for the treatment of 1 m3 of wastewater was found to be only 8.7 kg CO2 m−3, which is approx. 1.6% of the total CO2 emissions of the treatment of the daily effluents of a Cypriot resident. Nevertheless, alternative scenarios were investigated, in order to further enhance its overall environmental performance.

CONCLUSIONS

The results indicate that the majority of the environmental impacts of this process could be attributed to indirect emissions, tracing back to electricity generation, followed by emissions from the chemicals used. The most critical improvement identified herein, is the use of a renewable energy source. © 2016 Society of Chemical Industry
Crime linkage of sex offences in Japan by multiple correspondence analysis
Authors: Yokota Kaeko , Watanabe Kazumi , Wachi Taeko , Otsuka Yusuke , Hirama Kazuki , Fujita Goro
Published: October 2016

This study examined the effectiveness of multiple correspondence analysis (MCA) for linking crimes. The data consisted of 720 incidents committed by 360 individual offenders of serial criminal sexual contact cases (i.e., rape and forced indecency). According to the measured similarity obtained from the Euclidean distance in the MCA configuration, a rank‐score was assigned to each linked pair and unlinked pair. The validity of MCA for linking crimes was evaluated with a 10‐fold cross‐validation procedure and a receiver operating characteristic analysis. The t‐test of rank scores showed a statistically significant difference between linked pairs and unlinked pairs (t(641.43) = −18.53, p < .001, d = 1.38). The value of the area under the receiver operating characteristic curve was .83 (95% CI = .80–.86), indicating a high level of discriminative accuracy in distinguishing offences committed by the same person from those committed by different persons.
Three‐dimensional T1 and T2* mapping of human lung parenchyma using interleaved saturation recovery with dual echo ultrashort echo time imaging (ITSR‐DUTE)
Authors: Gai Neville D. , Malayeri Ashkan A. , Bluemke David A.
Published: October 2016

Purpose

To develop and assess a new technique for three‐dimensional (3D) full lung T1 and T2* mapping using a single free breathing scan during a clinically feasible time.

Materials and Methods

A 3D stack of dual‐echo ultrashort echo time (UTE) radial acquisition interleaved with and without a WET (water suppression enhanced through T1 effects) saturation pulse was used to map T1 and T2* simultaneously in a single scan. Correction for modulation due to multiple views per segment was derived. Bloch simulations were performed to study saturation pulse excitation profile on lung tissue. Optimization of the saturation delay time (for T1 mapping) and echo time (for T2* mapping) was performed. Monte Carlo simulation was done to predict accuracy and precision of the sequence with signal‐to‐noise ratio of in vivo images used in the simulation. A phantom study was carried out using the 3D interleaved saturation recovery with dual echo ultrashort echo time imaging (ITSR‐DUTE) sequence and reference standard inversion recovery spin echo sequence (IR‐SE) to compare accuracy of the sequence. Nine healthy volunteers were imaged and mean (SD) of T1 and T2* in lung parenchyma at 3T were estimated through manually assisted segmentation. 3D lung coverage with a resolution of 2.5 × 2.5 × 6 mm3 was performed and nominal scan time was recorded for the scans. Repeatability was assessed in three of the volunteers. Regional differences in T1/T2* values were also assessed.

Results

The phantom study showed accuracy of T1 values to be within 2.3% of values obtained from IR‐SE. Mean T1 value in lung parenchyma was 1002 ± 82 ms while T2* was 0.85 ± 0.1 ms. Scan time was ∼10 min for volunteer scans. Mean coefficient of variation (CV) across slices was 0.057 and 0.09, respectively. Regional variation along the gravitational direction and between right and left lung were not significant (P = 0.25 and P = 0.06, respectively) for T1. T2* showed significant variation (P = 0.03) along the gravitational direction. Repeatability for three volunteers was within 0.7% for T1 and 1.9% for T2*.

Conclusion

3D T1 and T2* maps of the entire lung can be obtained in a single scan of ∼10 min with a resolution of 2.5 × 2.5 × 6 mm3.

Level of Evidence: 2

J. Magn. Reson. Imaging 2017;45:1097–1104
Esophageal carcinoma: Ex vivo evaluation by high‐spatial‐resolution T2‐mapping MRI compared with histopathological findings at 3.0T
Authors: Wei Yi , Wu Sen , Gao Feifei , Sun Tingyi , Zheng Dandan , Ning Peigang , Zhao Cuihua , Li Ziyuan , Li Xiaodong , Li Linlin , Zhu Shaocheng
Published: October 2016

Purpose

To prospectively determine the feasibility of T2‐mapping magnetic resonance imaging (MRI) to quantitatively describe the signal characteristics of the normal esophageal wall and assess the depth of esophageal wall invasion by carcinoma at 3.0T.

Materials and Methods

Thirty‐two patient specimens, each having foci of carcinoma, were studied using 3.0T MR. Freehand regions of interest were placed to measure the T2 value of the normal esophageal layers and were compared with the regions of carcinoma. Three independent readers reviewed the MR images to evaluate the depth of carcinoma invasion; when the three radiologists could not fully agree with each other, the final stage was determined by consensus. The Games‐Howell test was used to compare the difference between the normal esophageal layers and carcinoma. Spearman correlation coefficient analysis was used to compare the stage at MRI with that at histopathological analysis. The interobserver agreement was compared with Cohen's kappa. The sensitivity, specificity, and accuracy for detecting carcinoma invasion were calculated.

Results

The T2 values between the carcinoma and normal esophageal layers were different (all P < 0.01), except for the inner circular muscle (P = 0.511). The T2 value of each layer of the normal esophageal wall was also different from that of the adjacent layer (all P < 0.01). In 29 of 32 lesions, the depth of the esophageal wall invasion determined by MR was consistent with the histopathological stage (r = 0.969, P < 0.001). The sensitivity, specificity, and accuracy were 80%, 96.3%, and 93.8%, respectively, for invasion into the mucosa; 77.8%, 95.7%, and 90.6%, respectively, for invasion into submucosa; 100%, 95.8%, and 96.9%, respectively, for invasion into muscularis propria; and 100%, 100%, and 100%, respectively, for invasion into the adventitia.

Conclusion

T2‐mapping MR images obtained using a 3.0T MR scanner can be used to depict the precise histopathological layers of the esophageal wall clearly and provide excellent diagnostic accuracy for assessing esophageal carcinoma invasion.

Level of Evidence: 1

Technical Efficacy: Stage 2

J. MAGN. RESON. IMAGING 2017;45:1609–1616
Extracellular ATP induces graded reactive response of astrocytes and strengthens their antioxidative defense in vitro
Authors: Adzic Marija , Stevanovic Ivana , Josipovic Natasa , Laketa Danijela , Lavrnja Irena , Bjelobaba Ivana M. , Bozic Iva , Jovanovic Marija , Milosevic Milena , Nedeljkovic Nadezda
Published: October 2016

It is widely accepted that adenosine triphosphate (ATP) acts as a universal danger‐associated molecular pattern with several known mechanisms for immune cell activation. In the central nervous system, ATP activates microglia and astrocytes and induces a neuroinflammatory response. The aim of the present study was to describe responses of isolated astrocytes to increasing concentrations of ATP (5 µM to 1 mM), which were intended to mimic graded intensity of the extracellular stimulus. The results show that ATP induces graded activation response of astrocytes in terms of the cell proliferation, stellation, shape remodeling, and underlying actin and GFAP filament rearrangement, although the changes occurred without an apparent increase in GFAP and actin protein expression. On the other hand, ATP in the range of applied concentrations did not evoke IL‐1β release from cultured astrocytes, nor did it modify the release from LPS and LPS+IFN‐γ–primed astrocytes. ATP did not promote astrocyte migration in the wound‐healing assay, nor did it increase production of reactive oxygen and nitrogen species and lipid peroxidation. Instead, ATP strengthened the antioxidative defense of astrocytes by inducing Cu/ZnSOD and MnSOD activities and by increasing their glutathione content. Our current results suggest that although ATP triggers several attributes of activated astrocytic phenotype with a magnitude that increases with the concentration, it is not sufficient to induce full‐blown reactive phenotype of astrocytes in vitro. © 2016 Wiley Periodicals, Inc.
Temporal patterns of precipitation and vegetation variability over Botswana during extreme dry and wet rainfall seasons
Authors: Mberego Seth
Published: October 2016

This study investigates the temporal evolution of extreme rainfall seasons over Botswana, and their relationships to the growing season cycle of natural vegetation. Ground‐based precipitation data and remotely sensed Advanced Very High Resolution Radiometer (AVHRR)‐normalized difference vegetation index (NDVI) data are analysed for the July 1981–June 2006 period. Results confirm that Botswana's annual cycle of precipitation is characterized by substantial intra‐seasonal variation, which is resonated in natural vegetation cover. During extreme wet (dry) years, the most extreme surpluses (shortfalls) of monthly rainfall were observed in the middle of the rainfall season (January–February). While rainfall receipts during season onset and cessation may not be the highest, they were found to have strong influence on NDVI coefficient of variation. Extreme wet seasons could be distinguished from moderate wet seasons by examining their monthly peak patterns. Furthermore, the November–December period was identified through the NDVI as the critical period when extreme conditions may begin to emerge. These findings could have important implications for supporting seasonal forecasts and optimizing rainfed agricultural adaptation and natural resources management in southern Africa.
High‐resolution habitat modeling with airborne LiDAR for red tree voles
Authors: Johnston Aaron N. , Moskal L. Monika
Published: October 2016

Habitat suitability maps are important tools for conservation planning and species investigations, but maps at resolutions that are biologically meaningful and useful for local‐level decision‐making are lacking for many species that use resources at fine scales. Airborne light detection and ranging (LiDAR) describes 3‐dimensional structure of forests and other habitats at high resolution, which can improve habitat models for many species and facilitate investigations otherwise impossible with field data or other remote‐sensing techniques. We used an information‐theoretic approach and logistic regression to model habitat of red tree voles (Arborimus longicaudus) at multiple spatial scales with predictors derived from airborne LiDAR in southwestern Oregon. We developed a priori models to evaluate habitat associations and identify good models useful for high‐resolution mapping of habitat suitability across a large spatial extent. Our best models that compared habitats around nest trees of red tree voles to available sites performed well (i.e., accuracy = 0.83) on an independent test data set. We found fair performance in comparisons of habitat around nest trees to unused locations within areas previously identified as red tree vole habitat (i.e., accuracy = 0.71). Red tree vole nests were often in the largest trees in the stand and away from forest edges. Both analyses suggested that fine‐ and broad‐scale predictors are important for modeling habitat of red tree voles. Habitat suitability for red tree voles should be predicted effectively by LiDAR acquisitions even with low point densities because maps were robust to reductions in point densities as low as 1 point/m2. We found that LiDAR was effective for modeling habitat of red tree voles and expect it to improve performance of models for other species with similar habitat requirements. © 2016 The Wildlife Society.
The past, present, and future of American university presses: A view from the left coast
Authors: Mudditt Alison
Published: October 2016

Key points

American university presses have proved remarkably resilient but now face a daunting set of internal and external challenges.

At the heart of university press challenges is the future of the monograph – critical to scholarship, resistant to change, and declining in sales volume.

Internal pressures on presses to be more accountable and self‐sustaining are growing.

Presses are beginning to address current challenges – individually and collectively – with energy and optimism and a renewed level of collaboration.
‘Being small is not a fault’: Making sense of the newer generation of German‐language university presses
Authors: Bargheer Margo , Pabst Jutta
Published: October 2016

Key points

There are 33 university presses in Germany, most of them part of the working group of German‐language university presses, AG Universitätsverlage.

Göttingen University Press was formed in the late 1990s as an open access service for the university's scholars.

A publishing house within the academic network is able to be more responsive to the needs of its institution and scholars than an external publisher solely relying on revenues.

Taking control of publishing helps academia ensure that results will be disseminated in a way most beneficial to itself and society.
Processes driving seasonal variability in DMS, DMSP, and DMSO concentrations and turnover in coastal Antarctic waters
Authors: Asher E. C. , Dacey J. W. H. , Stukel M. , Long M. C. , Tortell P. D.
Published: October 2016

This study presents new measurements of the concentrations and turnover rates of dimethyl sulfide (DMS), dimethylsulfoniopropionate (DMSP), and dimethyl sulfoxide (DMSO) in coastal waters near Palmer Station, Antarctica, during the spring and summer of 2012–2013. Using several novel analytical and experimental techniques, we document variability in DMS, DMSP, and DMSO (DMS/P/O) concentrations and quantify dominant production and removal terms in the mixed layer DMS budget. Our results demonstrate considerable seasonal variability in the concentration of DMS (range 0–20 nM), total DMSP (8–160 nM), and total DMSO (4–160 nM). Over the seasonal cycle, dissolved DMSP concentrations were well correlated with total DMSP concentrations and the abundance of Phaeocystis antarctica, while DMSO concentrations (total and dissolved) were well correlated with DMS concentrations. DMSP cleavage from the dissolved pool (mean rate = 5.5 nM d−1) and release from microzooplankton grazing (mean 5.6 nM d−1) were the dominant sources of DMS, with smaller DMS production rates associated with DMSO reduction from the dissolved pool (mean 2.6 nM d−1) and krill grazing (mean 0.82 nM d−1). Specific rate constants for DMSP cleavage were inversely related to net primary production. Bacterial uptake was a primary contributor to DMS removal (mean −12 nM d−1), and we observed a significant correlation between bacterial production and gross DMS loss rate constants. Estimated sea‐air flux and photo‐oxidation constituted secondary DMS sinks. Our experimental and analytical methods provide insight into the DMS/P/O cycle at Palmer Station, and a starting point for future studies examining inter‐annual DMS/P/O variability in coastal Antarctic waters.
Self‐Healing Polymer Networks Based on Reversible Michael Addition Reactions
Authors: Kuhl Natascha , Geitner Robert , Bose Ranjita K. , Bode Stefan , Dietzek Benjamin , Schmitt Michael , Popp Jürgen , Garcia Santiago J. , van der Zwaag Sybrand , Schubert Ulrich S. , Hager Martin D.
Published: October 2016

A new polymeric material utilizing a highly efficient as well as reversible thiol‐ene click reaction is presented. For this purpose, a trithiol is reacted with a bisbenzylcyanoacetamide derivative resulting in the formation of a dynamic polymer network. The self‐healing ability of this novel material is tested by scratch healing experiments. Healing is found to take place from 60 °C onward. The underlying healing mechanism is studied in detail using temperature‐dependent Raman spectroscopy confirming the reversible opening of the thiol‐ene adducts. Additionally, the thermal and mechanical properties are investigated by differential scanning calorimetry, thermogravimetric analysis, and rheological measurements proving the network formation as well as its reversibility during the thermal treatment.

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Online Review Helpfulness: Role of Qualitative Factors
Authors: Agnihotri Arpita , Bhattacharya Saurabh
Published: October 2016

Consumers are increasingly reading online reviews before making any purchasing decisions. The significance of online reviews has only grown over the years. Though in the past, scholars have emphasized the impact of quantitative factors (e.g., review ratings) on online reviews, only recently have they begun to explore the role of qualitative aspects of online reviews. Content readability and associated sentiments in text provide two important qualitative cues that influence the helpfulness of online reviews. However, the extant literature has overemphasized the linear association between these aspects and the helpfulness of reviews. Using the elaboration likelihood model and the classic ideal point concept, the current work asserts that after an ideal point is attained, lucid and sentimental reviews diminish in utility (i.e., helpfulness of an online review for consumers decreases). This may happen because consumers are wary of fraudulent reviews. This study proposes that if experienced reviewers give such extreme reviews, then consumers might still draw utility from these reviews. In other words, this study explains the moderating role of reviewer experience, which heuristically influences consumers’ trust of online reviews, thus making even too simplistic or extremely sentimental reviews helpful.
A Randomized Clinical Trial of Atomoxetine for Mild Cognitive Impairment in Parkinson's Disease
Authors: Hinson Vanessa K. , Delambo Amy , Elm Jordan , Turner Travis
Published: October 2016

Background

Mild cognitive impairment in Parkinson's disease (PD‐MCI) is associated with diminished norepinephrine from the locus coeruleus to the prefrontal cortex. Atomoxetine is a specific norepinephrine reuptake inhibitor that has been approved by the US Food and Drug Administration to treat attention deficit hyperactivity disorder in adults. The authors hypothesized that atomoxetine would improve attention and executive functioning in patients with PD‐MCI.

Methods

Thirty participants who met Movement Disorder Society Task Force Level I criteria for PD‐MCI were enrolled in a randomized controlled trial of atomoxetine. Cognitive evaluations were performed at baseline and after 10 weeks of treatment or placebo. A safety visit was performed at Week 12. A global statistical test was used to examine treatment effects on standardized tests of attention, working memory, processing speed, and set shifting (primary outcome measure). Secondary outcomes included cognitive measures hypothesized to be insensitive to atomoxetine, the Conners Adult Attention Deficit Hyperactivity Disorder Rating Scale, and safety measures.

Results

Fifteen participants were randomized to each arm. Groups were similar on medical and demographic variables and baseline cognition. Three serious adverse events occurred; 2 on atomoxetine (syncope, isolated episode of atrial fibrillation) and 1 on placebo (atrial fibrillation). The global statistical test of primary outcome measures did not reveal a significant difference between groups. However, significant improvements were observed for atomoxetine but not placebo on subjective measures of attention and impulsivity (Conners Adult Attention Deficit Hyperactivity Disorder Rating Scale).

Conclusions

Atomoxetine treatment produced subjective, but not objective, improvements in PD‐MCI. Failure to detect objective differences may be due to insensitivity of cognitive tests or severity of cognitive deficits in the study participants.
Anti‐HIV‐1 Activity Prediction of Novel Gp41 Inhibitors Using Structure‐Based Virtual Screening and Molecular Dynamics Simulation
Authors: Sepehri Saghi , Saghaie Lotfollah , Fassihi Afshin
Published: October 2016

The fusion of viral and host cell membranes is mediated using gp41 subunit of the human immunodeficiency virus type 1 (HIV‐1) envelope glycoprotein. As the HIV‐1 enters the host cells, the two helical regions (HR1 and HR2) in the ectodomain of gp41 form a six‐helix bundle, which carries the target and viral cell membranes to close proximity. Steps of this process serve as attractive targets for developing HIV‐1 fusion inhibitors. Identification of some novel HIV fusion inhibitors with the goal of blocking the formation of the six‐helix bundle was accomplished by computer‐aided drug design techniques. A virtual screening strategy was employed to recognize small molecules presumably able to bind the gp41 at the internal interface of the NHR helices at the core native viral six‐helix. This study was carried out in two stages. In the first stage, a library of more than seven thousand compounds was collected from ZINC, PubChem and BindingDB databases and protein data bank. Key contacts of known inhibitors with gp41 binding site residues were considered as the collecting criteria. In the second stage series of filtering processes were performed on this library in subsequent steps to find the potential gp41 inhibitors. The filtering criteria included pharmacokinetic and ADMET properties as well as in silico anti‐HIV‐1 prediction. Molecular docking simulation was carried out to identify interactions of the filtered molecules with the key residues in the gp41 binding site. Finally, molecular dynamics simulation indicates the superior inhibitory ability of three selected compounds over the known gp41inhibitor, NB‐64.
The long chain α–tocopherol metabolite α‐13’‐COOH and γ‐tocotrienol induce P‐glycoprotein expression and activity by activation of the pregnane X receptor in the intestinal cell line LS 180
Authors: Podszun Maren C. , Jakobi Metta , Birringer Marc , Weiss Johanna , Frank Jan
Published: October 2016

Scope

Members of the vitamin E family or their metabolites may induce the xenobiotic transporter P‐glycoprotein (P‐gp), which can limit the bioavailability of drugs and phytochemicals. This study aimed to investigate if α‐ and γ‐tocopherol, α‐ and γ‐tocotrienol, the long chain metabolite α‐tocopherol‐13’‐COOH, the short chain metabolites α‐ and γ‐carboxyethylhydroxychromanol and plastochromanol‐8 activate the pregnane X receptor (PXR) and thereby modulate P‐gp expression and/or activity.

Methods and results

P‐gp protein expression and activity were studied in LS 180 cells incubated with the respective test compound for 48 h. Furthermore, we determined if the compounds activate PXR in LS 180 cells, as PXR regulates P‐gp expression. Neither P‐gp protein expression and activity, nor PXR activity were influenced by α‐tocopherol, γ‐tocopherol and plastochromanol‐8. α‐Tocotrienol activated PXR in the reporter gene assay but did not induce protein expression or activity of P‐gp. γ‐Tocotrienol and α‐13’‐COOH activated PXR and induced protein expression and transporter activity of P‐gp.

Conclusion

Because the induction of P‐gp in the intestine may limit the systemic bioavailability of its substrates, the concurrent intake of drugs and γ‐tocotrienol and, if ever applicable, α‐13’‐COOH should be avoided.
The Cannabis Abuse Screening Test (CAST) revisited: examining measurement invariance by age
Authors: Sznitman Sharon R.
Published: October 2016

Defensible use of self‐reported cannabis use problem scales in age comparative frameworks requires that measured constructs have equal psychometric properties across age groups. This study compares the psychometric properties of the Cannabis Abuse Screening Test (CAST) across three age groups (18–24, 25–29, 30–40). Data was collected online from an accessible sample of 1316 cannabis users. Factor analysis compared the optimal factor structure and dimensionality diffraction. Multi‐group Model Invariance tests examined measurement invariance across the three age groups. CAST was two‐dimensional in all age groups with one factor measuring cannabis use problems and the other measuring deviation from a common standard of use. The two‐dimensional structure was more pronounced in older age groups. Weak factorial invariance was supported, suggesting that the meaning of the CAST factors is equivalent across age groups. Partial, but not full, strong factorial invariance was supported, indicating that only the cannabis use problem factor can be defensibly used to measure age group mean differences. Results confirm a well‐defined two‐dimensional CAST structure and factorial invariance across age groups. However, caution is needed when using the two items measuring deviation from a common standard in an age‐comparative framework. Replication studies based on a representative sample are needed.
Potential for high‐permittivity materials to reduce local SAR at a pacemaker lead tip during MRI of the head with a body transmit coil at 3 T
Authors: Yu Zidan , Xin Xuegang , Collins Christopher M.
Published: October 2016

Purpose

To illustrate the potential for high permittivity materials to be used in decreasing peak local SAR associated with implants when the imaging region is far from the implant.

Methods

We performed numerical simulations of a human subject with a pacemaker in a body‐sized birdcage coil driven at 128 MHz with and without a thin (5 mm) shell of material of high electric permittivity around the head.

Results

For a shell with relative permittivity of 600, the maximum specific energy absorption rate averaged over any 1 g of tissue near the pacemaker was reduced by 73.5% for a given B1 field strength at the center of the brain.

Conclusion

Although further study is required, initial simulations indicate that strategic use of high permittivity materials may broaden the conditions under which patients with certain implants can be imaged safely. Magn Reson Med 78:383–386, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Strom speichern mit neuen Materialien
Authors: Klaus Maximilian , Oetken Marco
Published: October 2016

Die dominierende Lithiumionen‐Akkumulatortechnik basiert auf Interkalationselektroden. Damit ist sie für die Schule zwar ein völlig neuartiger Typ wiederaufladbarer Batterien, Versuche damit sind dennoch möglich.