bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimizing wireless unicast and multicast sensor networks on the basis of evolutionary game theory
Authors: Chen Zhide , Qiao Cheng , Xu Li , Wu Wei
Published: June 2013

This paper presents two routing games, a unicast and a multicast routing game, for wireless sensor networks. We analyze the actions of nodes inside/outside lowest cost path (LCP) and draw their payoff functions. Our simulation shows that this evolutionary game theory scheme has several advantages over a widely used collusion–resistant routing scheme. All nodes, either out of LCP or in LCP, will ultimately choose the strategy ‘transmit’. To improve the payoff, nodes in LCP should either minimize their actual forwarding cost or maximize their claimed cost as long as it remains in the LCP, whereas minimizing the actual claimed cost is not an optimal option for nodes out of LCP. Copyright © 2013 John Wiley & Sons, Ltd.
Robust NMR Approaches for the Determination of Homonuclear Dipole–Dipole Coupling Constants in Studies of Solid Materials and Biomolecules
Authors: Saalwächter Kay
Published: June 2013

This review addresses the NMR spectroscopy study of molecular structure and dynamics by way of homonuclear dipole–dipole couplings by relying on their orientation and direct distance dependence. The study of homonuclear couplings as opposed to heteronuclear couplings poses specific challenges. On the one hand, two like spins cannot be independently manipulated easily, which means that simple shift‐refocusing concepts by using hard π pulses cannot be used to cope with potentially large chemical‐shift dispersions at the high fields used today. On the other hand, the noncommutativity of the different pair Hamiltonians in a multispin system leads to complications associated with the isolation of specific pair couplings while minimizing the influence of the other spins. In particular, the so‐called dipolar‐truncation effect challenges the observation of weak couplings of interest in the presence of stronger ones. Recent advances in determining homonuclear dipole–dipole coupling constants are reviewed, stressing the use of double‐quantum spectroscopy approaches and their similarity to the popular heteronuclear rotational‐echo double‐resonance experiment. Particular emphasis is put on corrections for the influence of transverse relaxation effects on the measured data, and the handling of distribution effects as well as potential dynamic heterogeneities in complex substances.
Angular stability of electric field‐induced effects in crystalline materials
Authors: Kushnir O. S. , Yurkevych O. V. , Andrushchak A. S.
Published: June 2013

We analyze angular bandwidths of extrema of the indicative surfaces describing spatial anisotropy of piezoelectric (PE) and electrooptic (EO) properties of doped lithium niobate (LiNbO3:MgO) and langasite (La3Ga5SiO14) crystals. A number of highly efficient experimental geometries are suggested, which are promising for PE and EO devices. Our data obtained with both analytical and numerical techniques characterize angular stability of those devices and, in particular, their angular aperture. We show that, besides of a maximal size of the electric field‐induced effects, ‘nondirect crystal cuts’ offer considerably higher angular stability of their characteristics, when compared with that typical for ‘direct crystal cuts’ usually employed in PE and EO devices.
Preparation of Glycerol Carbonate Esters by using Hybrid Nafion–Silica Catalyst
Authors: Climent María J. , Corma Avelino , Iborra Sara , Martínez‐Silvestre Sergio , Velty Alexandra
Published: June 2013

Glycerol carbonate esters (GCEs), which are valuable biomass‐derivative compounds, have been prepared through the direct esterification of glycerol carbonate and long organic acids with different chain lengths, in the absence of solvent, and with heterogeneous catalysts, including acidic‐organic resins, zeolites, and hybrid organic–inorganic acids. The best results, in terms of activity and selectivity towards GCEs, were obtained using a Nafion–silica composite. A full reaction scheme has been established, and it has been demonstrated that an undesired competing reaction results in the generation of glycerol and esters derived from a secondary hydrolysis of the endocyclic ester group, which is attributed to water formed during the esterification reaction. The influence of temperature, substrate ratio, catalyst‐to‐substrate ratio, and the use of solvent has been studied and, under optimized reaction conditions and with the adequate catalyst, it was possible to achieve 95 % selectivity for the desired product at 98 % conversion. It was demonstrated that the reaction rate decreased as the number of carbon atoms in the linear alkyl chain of the carboxylic acid increased for both p‐toluenesulfonic acid and Nafion–silica nanocomposite (Nafion SAC‐13) catalysts. After fitting the experimental data to a mechanistically based kinetic model, the reaction kinetic parameters for Nafion SAC‐13 catalysis were determined and compared for reactions involving different carboxylic acids. A kinetic study showed that the reduced reactivity of carboxylic acids with increasing chain lengths could be explained by inductive as well as steric effects.
A picopower temperature‐compensated, subthreshold CMOS voltage reference
Authors: Albano Domenico , Crupi Felice , Cucchi Francesca , Iannaccone Giuseppe
Published: June 2013

A voltage reference consisting of only two nMOS transistors with different threshold voltages is presented. Measurements performed on 23 samples from a single batch show a mean reference voltage of 275.4 mV. The subthreshold conduction and the low number of transistors enable to achieve a mean power consumption of only 40 pW. The minimum supply voltage is 0.45 V, which coincides with the lowest value reported so far. The mean TC in the temperature range from 0 to 120 °C is 105.4 ppm/°C, while the mean line sensitivity is 0.46%/V in the supply voltage range 0.45–1.8 V. The occupied area is 0.018 mm2. The power supply rejection rate without any filtering capacitor is −48 dB at 20 Hz and −29.2 dB at 10 kHz. Thanks to large area transistors and to a careful layout, the coefficient of variation of the reference voltage is only 0.62%. We introduce as a new figure of merit, the voltage temperature parameter (VTP), which gives a direct measure of the overall percentage variation of the reference voltage on the typical 2D domain of supply voltage and temperature. For the proposed circuit, the average VTP is 1.70% with a standard deviation of 0.21%. In order to investigate the effect of transistor area on process variability, a 4X replica of the proposed configuration has been fabricated and tested as well. Except for LS, the 4X replica doesn't exhibit any appreciable improvement with respect to the basic voltage reference. Copyright © 2013 John Wiley & Sons, Ltd.
Noisy spit: Parental noncompliance with child salivary cortisol sampling
Authors: Smith Victoria C. , Dougherty Lea R.
Published: June 2013

Studies assessing hypothalamic‐pituitary‐adrenal (HPA) axis functioning in young children commonly involve parental collection of salivary cortisol in ambulatory settings. However, no data are available on the compliance of parents in collecting ambulatory measures of children's salivary cortisol. This study examined the effects of parental compliance on the cortisol awakening response (CAR) and diurnal cortisol slopes in a sample of preschool‐age children (ages 3–5). Eighty‐one parents were instructed to collect their child's salivary cortisol samples upon their child's waking, 30 and 45 min post‐waking and before bedtime on two weekdays. Subjective parental compliance was assessed using parent‐report, and objective parental compliance was assessed using an electronic monitoring device. Rates of compliance were higher based on parent‐report than electronic monitoring. Parental noncompliance as indicated by electronic monitoring was associated with higher waking cortisol and lower CAR. Findings suggest the need to incorporate electronic monitoring of parental compliance into developmental neuroendocrine research, especially when assessing the CAR. © 2013 Wiley Periodicals, Inc. Dev Psychobiol 56: 647–656, 2014.
Effects of the kappa opioid receptor antagonist, nor‐binaltorphimine, on ethanol intake: Impact of age and sex
Authors: Morales Melissa , Anderson Rachel I. , Spear Linda P. , Varlinskaya Elena I.
Published: June 2013

The kappa opioid receptor (KOR) antagonist, nor‐binaltorphimine (nor‐BNI), was used to investigate the role of the KOR system in mediating ethanol intake. On P25 (adolescent) or P67 (adult) male and female rats were individually housed and given ad libitum access to food and water. The experimental procedure was initiated on P28 or P70: animals were given 30 min/day access to a 10% ethanol/supersaccharin solution every other day (3 baseline exposures). On the day after the final baseline test, rats were injected with nor‐BNI (0, 2.5, 5, 10 mg/kg), with testing initiated 24 hr later (30‐min access every other day, 3 test exposures). Nor‐BNI (10 mg/kg) increased ethanol intake in adult males, whereas the same dose decreased intake in adult females, suggesting pronounced sex differences in KOR‐associated mediation of ethanol intake in adulthood. There was no impact of nor‐BNI in adolescent animals of either sex, suggesting that the KOR may play less of a role in modulating ethanol intake during adolescence. © 2013 Wiley Periodicals, Inc. Dev Psychobiol 56: 700–712, 2014.
mRNA fluorescence in situ hybridization to determine overlapping gene expression in whole‐mount mouse embryos
Authors: Neufeld Stanley J. , Zhou Xiaolan , Vize Peter D. , Cobb John
Published: June 2013

Background: Whole‐mount in situ hybridization (ISH) is a prevalent tool to examine the spatial distribution of gene transcripts in intact embryos. Chromogenic‐based methods of signal development are commonly used in mouse embryos because of their high sensitivity. Fluorescence techniques, however, offer several advantages over chromogenic methods including the ability to visualize multiple signals in a specimen at once. Results: We describe a procedure for fluorescence in situ hybridization (FISH) for whole mouse embryos up to embryonic day 13.5. We show that this approach successfully produces a bright expression signal for several genes, validating the procedure in multiple tissues. Further, we show that double FISH can be used to visualize the expression of two genes in a single embryo by determining that Hoxd13 and Shh are co‐expressed in both the limb bud and the hindgut. Finally, we demonstrate that FISH can be paired with confocal microscopy to take optical sections of interior regions of the embryo. Conclusions: FISH is a valid alternative to chromogenic‐based ISH for visualizing gene expression in whole mouse embryos. This work provides a framework to add additional fluorescence signals in the mouse such as visualizing both mRNA and protein by pairing the procedure with immunofluorescence. Developmental Dynamics 242:1094–1100, 2013. © 2013 Wiley Periodicals, Inc.
An integrated modelling framework of catchment‐scale ecohydrological processes: 2. The role of water subsidy by overland flow on vegetation dynamics in a semi‐arid catchment
Authors: Niu Guo‐Yue , Troch Peter A. , Paniconi Claudio , Scott Russell L. , Durcik Matej , Zeng Xubin , Huxman Travis , Goodrich David , Pelletier Jon
Published: June 2013

In water‐limited regions, surface water and carbon fluxes are strongly controlled by soil water availability, which may be highly variable at very small spatial scales (e.g. metres) because of variations in terrain, soils, and vegetation conditions and to processes of water redistribution along hillslopes. This second of a two‐part paper first evaluates the performance of a newly developed ecohydrological model over a small semi‐arid experimental catchment (7·92 ha) in southeastern Arizona. Secondly, it investigates the effects of soil properties on water subsidy resulting from lateral overland flow re‐infiltration and on overall ecohydrological response.

With optimized parameters, the model shows a higher ability to simulate surface energy and water fluxes than CO2 fluxes at all temporal scales. The model simulates observed CO2 fluxes fairly well at diurnal scales during the main growing seasons and the interannual variability of these fluxes in response to soil moisture variations from drought years to wet years. However, the model reproduces less well carbon assimilation in spring and positive CO2 flux pulses following early monsoon rain events, suggesting a need for further development of the model's representations of multiple plant species and soil carbon decomposition. The model simulates soil moisture at 5 cm much better than at 15 cm mainly because of heterogeneous soil properties. Through five numerical experiments with varying saturated hydraulic conductivity values, it is revealed that the discharge at the outlet of this semi‐arid catchment is essentially attributed to lateral overland flow that is generated mainly by infiltration‐excess runoff. Subsurface flow plays a minor role in this semi‐arid catchment with a very deep groundwater table (>100 m). The model produces wetter soils in lowland areas along stream rills and channels through re‐infiltration of lateral overland flow. This water subsidy provides plants with favourable conditions to produce more leaves, CO2, and ET fluxes in lowland areas. Re‐infiltration of overland flow over complex terrain may play a role in buffering climatic impacts in a warming climate with fewer but more intense rainfall events in the Southwestern United States. Copyright © 2013 John Wiley & Sons, Ltd.
Complement C4 maintains peripheral B‐cell tolerance in a myeloid cell dependent manner
Authors: Chatterjee Priyadarshini , Agyemang Amma F. , Alimzhanov Marat B. , Degn Soren , Tsiftsoglou Stefanos A. , Alicot Elisabeth , Jones Sarah A. , Ma Minghe , Carroll Michael C.
Published: June 2013

The factors that allow self‐reactive B cells to escape negative selection and become activated remain poorly defined. Using a BCR knock‐in mouse strain, we identify a pathway by which B‐cell selection to nucleolar self‐antigens is complement dependent. Deficiency in complement component C4 led to a breakdown in the elimination of autoreactive B‐cell clones at the transitional stage, characterized by a relative increase in their response to a range of stimuli, entrance into follicles, and a greater propensity to form self‐reactive GCs. Using mixed BM chimeras, we found that the myeloid compartment was sufficient to restore negative selection in the autoreactive mice. A model is proposed in which in the absence of complement C4, inappropriate clearance of apoptotic debris promotes chronic activation of myeloid cells, allowing the maturation and activation of self‐reactive B‐cell clones leading to increased spontaneous formation of GCs.
Application of a Partial Least Squares Regression for the Determination of Nanomolar Concentrations of Scandium in the Presence of Nickel by Adsorptive Stripping Voltammetry
Authors: Jakubowska Małgorzata , Piech Robert , Górski Łukasz
Published: June 2013

This paper presents the methodology of a very sensitive determination of scandium in excess of nickel by adsorptive stripping voltammetry on a mercury film electrode and PLS regression. A calibration set consisting of binary mixtures containing 5, 15, 25, 35 or 45×10−9 M Sc(III) and simultaneously 0.5–50×10−7 M of Ni(II) was used to develop the chemometric PLS calibrations. An external set containing synthetic mixtures of 10, 20, 30, 40×10−9 M Sc(III) and the same Ni(II) concentration as mentioned above was used to validate the model and evaluate predictive ability. The application of data pretreatment techniques involving baseline correction, smoothing, range‐scaling, mean‐centering and their influence on the PLS model complexity, were also investigated. In the effect, the model for Sc(III), including 6 latent variables, was constructed. The model fulfills validation criteria and is characterized by a good prediction ability (majority of the prediction errors are lower than 10%). This work shows significant progress in the development of a very sensitive analytical technique for the determination of scandium in the presence of different concentrations of nickel by application of multivariate calibration tools.
High‐resolution methods for preserving the sum of mass fractions: improved χ‐scheme and an alternative
Authors: Syamlal Madhava , Benyahia Sofiane
Published: June 2013

When high resolution convection schemes are used for discretizing chemical species mass balance equations, the mass fractions are not guaranteed to add to one. We show that a proposed remedy called χ —scheme (Darwish and Moukalled, Comput. Methods Appl. Mech. Engrg. 192 (2003): 1711) will degrade to a diffusive first‐order scheme when a chemical species vanishes from the mixture, for example, because of chemical reactions. We propose an improvement to the χ ‐scheme to overcome this problem. Furthermore, a computationally efficient alternative scheme is proposed and evaluated with several examples, to quantify the improvements in the accuracy and the computational time. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Investigation of the Direct Methanol Fuel Cell with Novel Assembly Method
Authors: Yuan Z. Y. , Zhang Y. F. , Fu W. T. , Li Z. P. , Liu X. W.
Published: June 2013

Assembly pressure compresses the under part of the gas diffusion layer, and the inhomogeneous compression can cause performance variation of the direct methanol fuel cell. Compared with the cell with traditional assembly method using bolts at the corner of plates, the cell with a novel assembly method uniforming the pressure is designed, fabricated, and tested in this paper. First, a three‐dimensional model is developed to simulate the pressure distribution with different assembly patterns. Then, a multi‐physics simulation including methanol mass transport, methanol diffusion, and electron transport is conduced. The modeling results reveal that the novel assembly method can ensure the flatness of the membrane electrode when compared with the traditional method. The overall performance first increases and then decreases with the increase of assembly pressure, and the optimal pressure is 1.5 MPa. Additionally, the cell with both assembly methods are fabricated and tested under optimal condition, and there are only <8% discrepancy between the experimental results and simulation; Influences of cell efficiency patterned with two assembly methods are also studied.
Catalyst Degradation in High Temperature Proton Exchange Membrane Fuel Cells Based on Acid Doped Polybenzimidazole Membranes
Authors: Cleemann L. N. , Buazar F. , Li Q. , Jensen J. O. , Pan C. , Steenberg T. , Dai S. , Bjerrum N. J.
Published: June 2013

Degradation of carbon supported platinum catalysts is a major failure mode for the long term durability of high temperature proton exchange membrane fuel cells based on phosphoric acid doped polybenzimidazole membranes. With Vulcan carbon black as a reference, thermally treated carbon black and multi‐walled carbon nanotubes were used as supports for electrode catalysts and evaluated in accelerated durability tests under potential cycling at 150 °C. Measurements of open circuit voltage, area specific resistance and hydrogen permeation through the membrane were carried out, indicating little contribution of the membrane degradation to the performance losses during the potential cycling tests. As the major mechanism of the fuel cell performance degradation, the electrochemical active area of the cathodic catalysts showed a steady decrease in the cyclic voltammetric measurements, which was also confirmed by the post TEM and XRD analysis. A strong dependence of the fuel cell performance degradation on the catalyst supports was observed. Graphitization of the carbon blacks improved the stability and catalyst durability though at the expense of a significant decrease in the specific surface area. Multi‐walled carbon nanotubes as catalyst supports showed further significant improvement in the catalyst and fuel cell durability.
Operation of the Alkaline Direct Formate Fuel Cell in the Absence of Added Hydroxide
Authors: Nguyen T. Q. , Bartrom A. M. , Tran K. , Haan J. L.
Published: June 2013

The direct formate fuel cell (DFFC) has recently been demonstrated as a viable alkaline direct liquid fuel cell (DLFC) that does not require addition of hydroxide to the fuel stream for operation. In this work, we report that the DFFC can produce significant power at low temperatures without added hydroxide, especially when compared with other alkaline DLFCs powered by alcohols. Using oxygen at the cathode, the DFFC powered by 1 M HCOOK achieves a maximum power density of 106 mW cm–2 at 50 °C and 64 mW cm–2 at 23 °C. Using air at the cathode, the same DFFC achieves a maximum power density of 76 mW cm–2 at 50 °C and 27 mW cm–2 at 23 °C. These power densities were achieved without addition of hydroxide to the fuel stream. Constant current operation demonstrates that the maximum power density can be maintained at least for several hours of operation. Finally, we use electrochemical analysis to demonstrate that the formate oxidation reaction is not dependent on pH between 9 and 14, which permits the use of formate fuel without added hydroxide in the DFFC. An alkaline DLFC that does not require added hydroxide is promising for safe and practical operation.
Exergoeconomic Analysis of a Residential Hybrid PV‐Fuel Cell‐Battery System
Authors: Hosseini M. , Dincer I. , Rosen M. A.
Published: June 2013

A residential photovoltaic (PV)‐based hydrogen fuel cell (FC) system is analyzed using exergoeconomic methods, and its monthly performance is investigated. Mathematical models for predicting the power outputs of the PV and FC systems are presented. The results reported include the PV output and the shares attributable to the battery and the SOFC in supplying the electrical demand. Moreover, to study the performance of the hybrid system in supplying the daily demand, results are presented for two typical days in summer and winter. An exergoeconomic analysis is performed to determine the electricity unit cost over the system lifetime. The PV‐electrolyzer system is not able to produce a sufficient amount of hydrogen during winter days, so seasonal hydrogen storage is required to feed the FC. Power penetrations of the PV and the battery systems are at maxima during the summer months, while the penetration of the FC system reaches 67% in January and December. Due to its low efficiency (16%), the maximum exergy destruction occurs in the PV modules (86%). The unit cost of electricity varies on a monthly basis, reaching a minimum of 0.26 $ kWh–1 in July and a maximum of 1.8 $ kWh–1 in January and December.
Dynamic simulation of rainfall kinetic energy flux in a cloud resolving model
Authors: Nissan H. , Toumi R.
Published: June 2013

We present the first simulation of rainfall kinetic energy flux in a cloud resolving model. This demonstrates the potential for conducting erosion prediction studies using a regional climate model. Soil erosion is already a major global problem, and there is growing pressure on our land to deliver food and stability. Rainfall kinetic energy flux is an important variable in erosion prediction but is generally parameterized from intensity due to measurement difficulties. We show that a cloud resolving model can be used to dynamically simulate the kinetic energy of rain from basic physics, using four microphysics schemes. Results are within the range of observations and also capture the observed variability in kinetic energy for a given intensity. Large drops are shown to contribute disproportionately to total kinetic energy compared with their number, suggesting that several existing relations between terminal velocity and size of raindrops are poorly suited for kinetic energy modeling.
Serum interferon gamma level predicts recurrence in hepatocellular carcinoma patients after curative treatments
Authors: Lee I‐Cheng , Huang Yi‐Hsiang , Chau Gar‐Yang , Huo Teh‐Ia , Su Chien‐Wei , Wu Jaw‐Ching , Lin Han‐Chieh
Published: June 2013

Host immunity may have important role in the prognosis of hepatocellular carcinoma (HCC). The aim of this study was to evaluate the correlation between circulating immune regulators and clinical outcome in patients with HCC. Sixty‐three HCC patients were prospectively enrolled. Serum levels of interleukin‐10 (IL‐10), transforming growth factor‐beta (TGF‐β), interferon‐gamma (IFN‐γ) and interferon gamma‐inducible protein 10 (IP‐10) were measured, as well as the prevalence of regulatory T cells (Treg), NK+ T cells, invariant natural killer T cells (iNKT), programmed cell death‐1 (PD‐1)+CD8+ T cells, T helper 17 cells (Th17), CD69+ and CD45RO+ T cells in peripheral blood mononuclear cells (PBMC). Correlation between these immune regulators and clinical outcome were analyzed. A low serum IFN‐γ level (<50 pg/mL) was significantly associated tumor stage (BCLC stage B: 61.25% vs. stage A: 25%, p = 0.010) and tumor size (>5 cm: 53.8% vs. <5 cm: 25%, p = 0.047). Recurrence‐free survival was evaluated in 48 patients receiving curative treatment of HCC. By multivariate analysis, BCLC stage [hazard ratio (HR) = 32.180, p < 0.001], tumor size (HR = 15.373, p = 0.005), AST (HR = 3.796, p = 0.011) and IFN‐γ (HR = 0.354, p = 0.018) levels were independent factors associated with recurrence‐free survival. In conclusion, serum IFN‐γ level correlates with tumor stage and tumor size in HCC patients. Patients with lower baseline IFN‐γ levels have a higher risk of tumor recurrence after curative treatment. IFN‐γ may reflect host anti‐tumor immunity and may be a potential marker of HCC recurrence after curative treatment.
Fetal growth and childhood acute lymphoblastic leukemia: Findings from the childhood leukemia international consortium
Authors: Milne Elizabeth , Greenop Kathryn R. , Metayer Catherine , Schüz Joachim , Petridou Eleni , Pombo‐de‐Oliveira Maria S. , Infante‐Rivard Claire , Roman Eve , Dockerty John D. , Spector Logan G. , Koifman Sérgio , Orsi Laurent , Rudant Jérémie , Dessypris Nick , Simpson Jill , Lightfoot Tracy , Kaatsch Peter , Baka Margarita , Faro Alessandra , Armstrong Bruce K. , Clavel Jacqueline , Buffler Patricia A.
Published: June 2013

Positive associations have been reported between the measures of accelerated fetal growth and risk of childhood acute lymphoblastic leukemia (ALL). We investigated this association by pooling individual‐level data from 12 case–control studies participating in the Childhood Leukemia International Consortium. Two measures of fetal growth—weight‐for‐gestational‐age and proportion of optimal birth weight (POBW)—were analysed. Study‐specific odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, and combined in fixed effects meta‐analyses. Pooled analyses of all data were also undertaken using multivariable logistic regression. Subgroup analyses were undertaken when possible. Data on weight for gestational age were available for 7,348 cases and 12,489 controls from all 12 studies and POBW data were available for 1,680 cases and 3,139 controls from three studies. The summary ORs from the meta‐analyses were 1.24 (95% CI: 1.13, 1.36) for children who were large for gestational age relative to appropriate for gestational age, and 1.16 (95% CI: 1.09, 1.24) for a one‐standard deviation increase in POBW. The pooled analyses produced similar results. The summary and pooled ORs for small‐for‐gestational‐age children were 0.83 (95% CI: 0.75, 0.92) and 0.86 (95% CI: 0.77, 0.95), respectively. Results were consistent across subgroups defined by sex, ethnicity and immunophenotype, and when the analysis was restricted to children who did not have high birth weight. The evidence that accelerated fetal growth is associated with a modest increased risk of childhood ALL is strong and consistent with known biological mechanisms involving insulin‐like growth factors. © 2013 UICC
Association between circulating concentrations of 25(OH)D and colorectal adenoma: A pooled analysis
Authors: Jacobs Elizabeth T. , Hibler Elizabeth A. , Lance Peter , Sardo Christine L. , Jurutka Peter W.
Published: June 2013

The relationship between the biomarker of vitamin D status, 25(OH)D, and the risk for colorectal neoplasia is suggestive but equivocal. Questions remain regarding whether there are differential associations between 25(OH)D and colorectal adenoma by gender, colorectal subsite or features of baseline and recurrent adenomas. We sought to investigate the relationship between 25(OH)D and both baseline and recurrent adenoma characteristics. Our study was conducted among 2,074 participants in a pooled population of two clinical intervention trials of colorectal adenoma recurrence. A cross‐sectional analysis of 25(OH)D and baseline adenoma characteristics and a prospective study of recurrent adenomas and their characteristics were conducted. There was a statistically significant inverse association between the concentrations of 25(OH)D and the presence of three or more adenomas at baseline. Compared to participants with 25(OH)D levels of <20 ng/mL, the adjusted odds ratios (ORs) (95% condifdence intervals [CIs]) were 0.99 (0.70–1.41) for those with concentrations of ≥20 and <30 ng/mL, and 0.73 (0.50–1.06) among participants with levels of ≥30 ng/mL (p‐trend = 0.05). Baseline villous histology was also significantly inversely related to 25(OH)D levels (p‐trend = 0.04). Conversely, 25(OH)D concentrations were not associated with overall colorectal adenoma recurrence, with ORs (95% CIs) of 0.91 (0.71–1.17) and 0.95 (0.73–1.24; p‐trend = 0.85). These findings support the concept that the relationship between vitamin D and colorectal neoplasia may vary by stage of adenoma development.
Enhanced antitumor activity mediated by human 4‐1BB‐engineered T cells
Authors: Daniel‐Meshulam Inbal , Horovitz‐Fried Miryam , Cohen Cyrille J.
Published: June 2013

4‐1BB (CD137) is a costimulatory molecule transiently expressed on the T‐cell surface after TCR engagement, whereas its ligand 4‐1BBL can be found on professional antigen‐presenting cells, but more importantly, also on tumor cells. As the role of the 4‐1BB/4‐1BBL pathway has emerged central to CD8+ T‐cell responses and survival, we sought to test its relevance in the context of genetically modified human T cells. To that end, T cells purified from healthy donors and from vaccinated‐melanoma patients were transduced to express high levels of constitutive 4‐1BB. 4‐1BB‐transduced T cells were cocultured with melanoma tumor lines and exhibited enhanced cytokine secretion, upregulation of activation markers as well as increased cytotoxicity in a chick‐chorioallantoic membrane model of human melanoma tumors. In addition, these cells expanded and proliferated at a higher rate, expressed heightened levels of the antiapoptotic molecule BclXL and were also relatively insensitive to immunosuppression mediated by transforming growth factor‐β, compared to control cells. We also show that 4‐1BBL expression on the target cell is essential to 4‐1BB‐mediated functional improvement. Overall, we conclude that the modification of human T cells with 4‐1BB yields enhanced antitumor function which may have important applications in therapies based on the genetic modification of patient lymphocytes.
Effect of atmospheric gas plasmas on cancer cell signaling
Authors: Ishaq Musarat , Evans Margaret (Meg) , Ostrikov Kostya (Ken)
Published: June 2013

Cancer is one of the most life‐threatening diseases with many forms still regarded as incurable. The conventional cancer treatments have unwanted side effects such as the death of normal cells. A therapy that can accurately target and effectively kill tumor cells could address the inadequacies of the available therapies. Atmospheric gas plasmas (AGP) that are able to specifically kill cancerous cells offer a promising alternative approach compared to conventional therapies. AGP have been shown to exploit tumor‐specific genetic defects and a recent trial in mice has confirmed its antitumor effects. The mechanism by which the AGP act on tumor cells but not normal cells is not fully understood. A review of the current literature suggests that reactive oxygen species (ROS) generated by AGP induce death of cancer cells by impairing the function of intracellular regulatory factors. The majority of cancer cells are defective in tumor suppressors that interfere normal cell growth pathways. It appears that pro‐oncogene or tumor suppressor‐dependent regulation of antioxidant/or ROS signaling pathways may be involved in AGP‐induced cancer cell death. The toxic effects of ROS are mitigated by normal cells by adjustment of their metabolic pathways. On the other hand, tumor cells are mostly defective in several regulatory signaling pathways which lead to the loss of metabolic balance within the cells and consequently, the regulation of cell growth. This review article evaluates the impact of AGP on the activation of cellular signaling and its importance for exploring mechanisms for safe and efficient anticancer therapies.
Differential urinary specific gravity as a molecular phenotype of the bladder cancer genetic association in the urea transporter gene, SLC14A1
Authors: Koutros Stella , Baris Dalsu , Fischer Alexander , Tang Wei , Garcia‐Closas Montserrat , Karagas Margaret R. , Schwenn Molly , Johnson Alison , Figueroa Jonine , Waddell Richard , Prokunina‐Olsson Ludmila , Rothman Nathaniel , Silverman Debra T.
Published: June 2013

Genome‐wide association studies (GWAS) identified associations between markers within the solute carrier family 14 (urea transporter), member 1 (SLC14A1) gene and risk of bladder cancer. SLC14A1 defines the Kidd blood groups in erythrocytes and is also involved in concentration of the urine in the kidney. We evaluated the association between a representative genetic variant (rs10775480) of SLC14A1 and urine concentration, as measured by urinary specific gravity (USG), in a subset of 275 population‐based controls enrolled in the New England Bladder Cancer Study. Overnight urine samples were collected, and USG was measured using refractometry. Analysis of covariance was used to estimate adjusted least square means for USG in relation to rs10775480. We also examined the mRNA expression of both urea transporters, SLC14A1 and SLC14A2, in a panel of human tissues. USG was decreased with each copy of the rs10775480 risk T allele (p‐trend = 0.011) with a significant difference observed for CC vs. TT genotypes (p‐valuetukey = 0.024). RNA‐sequencing in the bladder tissue showed high expression of SLC14A1 and the absence of SLC14A2, while both transporters were expressed in the kidney. We suggest that the molecular phenotype of this GWAS finding is the genotype‐specific biological activity of SLC14A1 in the bladder tissue. Our data suggest that SLC14A1 could be a unique urea transporter in the bladder that has the ability to influence urine concentration and that this mechanism might explain the increased bladder cancer susceptibility associated with rs10775480.
ANALYSIS OF TRACING ABILITY OF DIFFERENT SIZED PARTICLES IN DRIP IRRIGATION EMITTERS WITH COMPUTATIONAL FLUID DYNAMICS
Authors: Li Yunkai , Liu Haisheng , Yang Peiling , Wu Dan
Published: June 2013

The tracing ability of particles in the flow path is the key to digital particle image velocimetry (DPIV) testing and clogging control in drip irrigation emitters. Six different kinds of particles with respective diameters of 0.01, 0.02, 0.04, 0.05, 0.06 and 0.08 mm were considered, and the tracing ability was carried out by using the computational fluid dynamics (CFD) turbulence simulation method. Results showed that standard k‐ε model could well describe the transportation process of particles in drip irrigation emitters in terms of precision, applicable extensibility and computational expense. Clogging most likely occurred in the corner of the whole flow path of the drip irrigation emitter region, sections 1 and 8 plus sections 4 and 5. The tracing ability of the particles of 0.01 mm diameter was good enough to be used for a single‐phase test. And for a two‐phase test, diameters of the particles should be more than 0.04 mm. Copyright © 2013 John Wiley & Sons, Ltd.
Preparation of Ce‐doped TiO2 Hollow Fibers and Their Photocatalytic Degradation Properties for Dye Compound
Authors: Shi Zhongliang , Zhou Mingtao , Zheng Dongsong , Liu Hao , Yao Shuhua
Published: June 2013

Cerium‐doped titanium dioxide (TiO2) with a hollow fiber structure was successfully prepared using ammonium ceric nitrate and tetrabutyltitanate as precursors and cotton fiber as the template. The effects of cerium (Ce)‐doping on the crystallite sizes, crystal pattern, and optical property of the prepared catalysts were investigated by means of techniques such as scanning electron microscopy (SEM), X‐ray diffraction (XRD), BET surface area, and UV‐vis diffuse absorption spectroscopy. SEM observation showed that the prepared TiO2 fibers possessed fibrous shape inherited from the cotton fiber and had a hollow structure. As confirmed by XRD and UV‐vis diffuse absorption spectroscopy examinations, Ce‐doping restrained the growth of grain size and extended the photoabsorption edge of TiO2 hollow fiber into the visible light region. The present photocatalyst showed higher photocatalytic reactivity in photodegradation of highly concentrated methylene blue (MB) solutions than pure TiO2 under UV and visible light, and the amount of Ce‐doped significantly affected the catalytic property. In the experiment condition, the photocatalytic activity of 0.5 mol% Ce‐doped TiO2 fiber was optimal of all the prepared samples. In addition, the possibility of cyclic usage of the photocatalyst was also confirmed. The material was easily removed by centrifugal separation. Therefore, using the template method and by doping with cerium, TiO2 may hopefully become a low‐energy consuming, high activity and green environmentally friendly catalytic material.
Luminescence and Spectroscopic Studies of (Y0.99Ce0.01)3OF3S2: A New Orange Yellow‐emitting Oxyfluorosulfide Phosphor for LEDs
Authors: Chen Shing‐Nian , Chen Teng‐Ming
Published: June 2013

A new Ce3+‐doped oxyfluorosulfide phosphor, Y3OF3S2:Ce33+ has been investigated as a new candidate for potential application in phosphor‐converted light emitting diodes (pc‐LEDs). The synthesized Y3OF3S2:Ce33+ was characterized by powder X‐ray diffraction and various spectroscopic techniques. Y3OF3S2:Ce33+ can be excited by wide‐range (250‐400 nm) radiation and shows yellow‐orange broadband emission peaking at 610 nm with a quantum efficiency of 40%. These results indicate it may serve as a promising phosphor in near‐UV pc‐LEDs.
DELAYED‐ONSET PTSD AFTER COMBAT: THE ROLE OF SOCIAL RESOURCES
Authors: Horesh Danny , Solomon Zahava , Ein‐Dor Tsachi
Published: June 2013

Delayed‐onset posttraumatic stress disorder (DPTSD) has been under medico‐legal debate for years. Previous studies examining the prevalence and underlying mechanisms of DPTSD have yielded inconclusive findings. This study examined the role of social resources and warzone exposure in DPTSD. Six hundred and seventy‐five Israeli veterans from the 1982 Lebanon War, 369 with antecedent combat stress reaction (CSR) and 306 without CSR, were assessed prospectively, 1, 2, and 20 years after the war. Veterans were divided into 4 groups, according to the time of first PTSD onset (first onset at 1983, 1984, and 2002 and no‐PTSD onset). Participants completed self‐report questionnaires tapping various social resources (social network support, family environment, military company environment, homecoming reception), as well as subjective and objective warzone exposure. Our results show that a significant portion (16.5%) of the veterans reported DPTSD. As hypothesized, social resources were found to be implicated in DPTSD. Interestingly, however, social resources accounted for long—not short—delays in PTSD onset. In addition, higher levels of both objective and subjective battle exposure were associated with a more immediate PTSD onset. Finally, CSR was found to be the most powerful predictor of DPTSD. Theoretical and clinical implications of these findings are discussed.
RISK AND PROTECTIVE FACTORS FOR DRUG USE AND PARTNER VIOLENCE AMONG WOMEN IN EMERGENCY CARE
Authors: Gilbert Louisa , El‐Bassel Nabila , Chang Mingway , Shaw Stacey A. , Wu Elwin , Roy Lolita
Published: June 2013

This study estimates the effects of multilevel risk and protective factors on the co‐occurrence of drug use and intimate partner violence (IPV) victimization among a randomly selected sample of 241 women seeking emergency care in the Bronx, New York. Twenty percent of the sample reported both using drugs and experiencing IPV in the past 6 months. Multinomial logistic regression results indicate that childhood sexual abuse, incarceration history, psychological distress, binge drinking, partner drug use, and lower relationship decision‐making power are associated with both IPV victimization and drug use. The multilevel risk and protective factors associated with both IPV and drug use represent a combination of factors that are differentially associated with drug use only and with IPV victimization only outcomes. These findings suggest that women receiving emergency care who present both drug use and IPV are likely to need a greater range of services and more intensive interventions to address their cumulative risks.
Enhancement of pollutants removal from real sewage by embedding microbial fuel cell in anaerobic–anoxic–oxic wastewater treatment process
Authors: Xie Beizhen , Dong Wenbo , Liu Bojie , Liu Hong
Published: June 2013

BACKGROUND

Developing an economical biological nitrogen and phosphorus removal technology with high efficiency has become a research priority in current sewage treatment procedures. In order to solve the problems within the anaerobic–anoxic–oxic (A2/O) process, including substrates competition and high energy consumption, a microbial fuel cell (MFC) was embedded in the A2/O process to enhance the efficiencies of removal of nitrogen and phosphorus, along with electricity production.

RESULTS

Three A2/O reactors, one with an embedded MFC, were set up, and nitrogen and phosphorus removal efficiencies and electricity generation were investigated. At the stage of stable operation, the chemical oxygen demand, total nitrogen and total phosphorus removal efficiencies of the MFC‐A2/O reactor, compared with the control, were increased by 15.9%, 9.3% and 1.4% on average, respectively. The average output power density of the MFC was 14.3 ± 1.4 mW m−3 and the internal resistance was 6000 Ω. Grey relational analysis was applied to study the most significant operational parameter of the A2/O process affecting electricity production of the MFC.

CONCLUSIONS

This research proved that nitrogen and phosphorus removal efficiency could be improved by embedding an MFC in the A2/O process. In addition, the MFC‐A2/O reactor can generate electricity continuously. © 2013 Society of Chemical Industry
Suppression of methanogenic activity in anaerobic granular biomass for hydrogen production
Authors: Hernández‐Mendoza Christian E. , Buitrón Germán
Published: June 2013

BACKGROUND

Several pretreatment methods at lab‐scale have been developed to inactivate methane‐producing and hydrogen‐consuming microorganisms. The need to obtain a hydrogen‐producing inoculum by a more practical method is still necessary. The objective of this study was to evaluate the adaptation of anaerobic granules to suppress the methanogenic activity for hydrogen production.

RESULTS

Preliminary tests in discontinuous operation indicated that methanogenic bacteria were hardly suppressed. The continuous adaptation of the granules, at pH of 4.5 and HRT of 5.5 h, produced hydrogen and successfully suppressed the methanogenic activity. An even distribution of β‐polysaccharides and cells was observed when the adapted granules were stained with fluorescent molecular tags. The reactor productivity was 71 ± 6 mL‐H2 Lreactor−1 h−1 with a yield of 2.6 ± 0.2 mol H2 mol–1 glucose.

CONCLUSION

Hydrogen was produced from methanogenic granules. The continuous strategy successfully suppressed the methanogenic activity of the seeded granules and the hydrogen production was stable. The high yield and even distribution of cells suggests that the continuous adaptation generated a more active biomass due to an improved mass transfer present in the process. © 2013 Society of Chemical Industry
Waste Nitrogen Metabolism and Excretion in Zebrafish Embryos: Effects of Light, Ammonia, and Nicotinamide
Authors: BUCKING CAROL , LEMOINE CHRISTOPHE M.R. , WALSH PATRICK J.
Published: June 2013

Bony fish primarily excrete ammonia as adults however the persistence of urea cycle genes may reflect a beneficial role for urea production during embryonic stages in protecting the embryo from toxic effects of ammonia produced from a highly nitrogenous yolk. This study aimed to examine the dynamic scope for changes in rates of urea synthesis and excretion in one such species (zebrafish, Danio rerio) by manipulating the intrinsic developmental rate (by alteration of light:dark cycles), as well as by direct chemical manipulation via ammonia injection (to potentially activate urea production) and nicotinamide exposure (to potentially inhibit urea production). Continuous dark exposure delayed development in embryos as evidenced by delayed appearance of hallmark anatomical features (heartbeat, eye pigmentation, body pigmentation, lateral line, fin buds) at 30 and 48 hr post‐fertilization, as well by a lower hatching rate compared to embryos reared in continuous light. Both ammonia and urea excretion were similarly effected and were generally higher in embryos continuously exposed to light. Ammonia injection resulted in significant increases (up to fourfold) of urea N excretion and no changes to ammonia excretion rates along with modest increases in yolk ammonia content during 2–6 hr post‐injection. Nicotinamide (an inhibitor of urea synthesis in mammals) reduced the ammonia‐induced increase in urea excretion and led to retention of ammonia in the yolk and body of the embryo. Our results indicate that there is a relatively rapid and large scope for increases in urea production/excretion rates in developing embryos. Potential mechanisms for these increases are discussed. J. Exp. Zool. 319A: 391–403, 2013. © 2013 Wiley Periodicals, Inc.
Detection of microseismic compressional (P) body waves aided by numerical modeling of oceanic noise sources
Authors: Obrebski Mathias , Ardhuin Fabrice , Stutzmann Eleonore , Schimmel Martin
Published: June 2013

Among the different types of waves embedded in seismic noise, body waves present appealing properties but are still challenging to extract. Here we first validate recent improvements in numerical modeling of microseismic compressional (P) body waves and then show how this tool allows fast detection and location of their sources. We compute sources at ~0.2 Hz within typical P teleseismic distances (30–90°) from the Southern California Seismic Network and analyze the most significant discrete sources. The locations and relative strengths of the computed sources are validated by the good agreement with beam‐forming analysis. These 54 noise sources exhibit a highly heterogeneous distribution, and cluster along the usual storm tracks in the Pacific and Atlantic oceans. They are mostly induced in the open ocean, at or near water depths of 2800 and 5600 km, most likely within storms or where ocean waves propagating as swell meet another swell or wind sea. We then emphasize two particularly strong storms to describe how they generate noise sources in their wake. We also use these two specific noise bursts to illustrate the differences between microseismic body and surface waves in terms of source distribution and resulting recordable ground motion. The different patterns between body and surface waves result from distinctive amplification of ocean wave‐induced pressure perturbation and different seismic attenuation. Our study demonstrates the potential of numerical modeling to provide fast and accurate constraints on where and when to expect microseismic body waves, with implications for seismic imaging and climate studies.