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Oxidation of graphite components could influence their designed life in a high-temperature nuclear reactor. The oxidized regions could potentially lower the allowed stress capacity. The American Society of Mechanical Engineers rules for the design and construction of graphite-moderated reactors recommend that subsurface regions that might become excessively damaged by oxidation during reactor operation be identified and excluded from geometry and stress calculations. Identification of oxidation-affected regions is possible, in principle, through complex modeling exercises of reactor behavior during hypothetical accident scenarios coupled with graphite oxidation models, but this procedure may not have the precision needed for informed decisions. This paper proposes an alternate method, based on interpretation of a series of well-designed oxidation experiments, which could augment the designer's tools. The procedure is illustrated by data on oxidation by air of several graphite grades (NBG-18, PCEA, IG-110, R4-650) that are corroborated with independent literature information, when available. The Wichner model for graphite oxidation used for this analysis provides conservative results that could be quickly implemented in the design process. [Display omitted] [ABSTRACT FROM AUTHOR]

Polyglutamylation is a posttranslational modification (PTM) that adds several glutamates on glutamate residues in the form of conjugated peptide chains by a family of enzymes known as polyglutamylases. Polyglutamylation is well documented in microtubules. Polyglutamylated microtubules consist of different α- and β-tubulin subunits with varied number of added glutamate residues. Kinetic control and catalytic rates of tubulin modification by polyglutamylases influence the polyglutamylation pattern of functional microtubules. The recent studies uncovered catalytic mechanisms of the glutamylation enzymes family, particularly tubulin tyrosine ligase-like (TTLL). Variable length polyglutamylation of primary sequence glutamyl residues have been mapped with a multitude of protein chemistry and proteomics approaches. Although polyglutamylation was initially considered a tubulin-specific modification, the recent studies have uncovered a calmodulin-dependent glutamylase, SidJ. Nano-electrospray ionization (ESI) proteomic approaches have identified quantifiable polyglutamylated sites in specific substrates. Indeed, conjugated glutamylated peptides were used in nano-liquid chromatography gradient delivery due to their relative hydrophobicity for their tandem mass spectrometry (MS/MS) characterization. The recent polyglutamylation characterization has revealed three major sites: E445 in α-tubulin, E435 in β-tubulin, and E860 in SdeA. In this review, we have summarized the progress made using proteomic approaches for large-scale detection of polyglutamylated peptides, including biology and analysis. [ABSTRACT FROM AUTHOR]

Background: Health disparities are pervasive and are linked to economic losses in the United States of up to $135 billion per year. The Flint Center for Health Equity Solutions (FCHES) is a Transdisciplinary Collaborative Center for health disparities research funded by the National Institute of Minority Health and Health Disparities (NIMHD). The purpose of this study was to estimate the economic impact of the 5-year investment in FCHES in Genesee County, Michigan.Methods: The estimated impacts of FCHES were calculated using a U.S.-specific input/output (I/O) model, IMPLAN, from IMPLAN Group, LLC., which provides a software system to access geographic specific data regarding economic sector interactions from a variety of sources. This allowed us to model the cross-sector economic activity that occurred throughout Genesee County, Michigan, as a result of the FCHES investment. The overall economic impacts were estimated as the sum of three impact types: 1. Direct (the specific expenditures impact of FCHES and the Scientific Research and Development Services sector); 2. Indirect (the impact on suppliers to FCHES and the Scientific Research and Development Services sector); and 3. Induced (the additional economic impact of the spending of these suppliers and employees in the county economy).Results: The total FCHES investment amounted to approximately $11 million between 2016 and 2020. Overall, combined direct, indirect, and induced impacts of the total FCHES federal investment in Genesee County included over 161 job-years, over $7.6 million in personal income, and more than $19.2 million in economic output. In addition, this combined economic activity generated close to $2.3 million in state/local and federal tax revenue. The impact multipliers show the ripple effect of the FCHES investment. For example, the overall output of over $19.2 million led to an impact multiplier of 1.75 - every $1 of federal FCHES investment led to an additional $.75 of economic output in Genesee County.Conclusions: The FCHES research funding yields significant direct economic impacts above and beyond the direct NIH investment of $11 million. The economic impact estimation method may be relevant and generalizable to other large research centers such as FCHES. [ABSTRACT FROM AUTHOR]

Contrasting conditions of different habitats lead to geographic variation among populations of the same species. In widespread species, trait divergence represents a response to spatial variation in local habitat conditions and biotic interactions. Morphology and call characteristics are crucial for anuran fitness because of their direct impacts on survival and reproduction. Our aim was to analyse and compare morphological and call characteristics of two populations of Dryophytes arenicolor in central Mexico where waterbody types and presence of other species (D. eximius) differed. We measured morphological characteristics, estimated the sex ratio, and characterised the advertisement calls for each population. We found that the sex ratio differed among populations: in one population, the sex ratio was male-biased. No morphological variation was detected between populations; however, females had longer limbs and higher mass. We found differences in call characteristics among populations and even among individuals of the same population. There was an effect of calling context (solitary or chorus) on call characteristics, we found that calls from conspecifics led to an increase in values of spectral characteristics and reduction of temporal ones, whereas calls from D. eximius resulted in a decrease in values of spectral characteristics and increase in temporal ones. [ABSTRACT FROM AUTHOR]

An electron microscopy investigation was performed to understand the relationship between the microstructure and properties of carbonized cellulose and lignin (softwood kraft lignin) relative to the structure of the original biomass components. Structure details at micro- and molecular levels were investigated by scanning transmission electron microscopy. Atomic-resolution images revealed the presence of random disordered carbon in carbonized cellulose (C-CNC) and of large domains of well-ordered carbon with graphite sheet structure in carbonized lignin (C-Lignin). These structural differences explain why C-CNC exhibits higher surface area and porosity than C-Lignin. The presence of certain well-ordered carbon in carbonized lignin indicates some of the carbon in lignin are graphitized with heat treatment temperature up to 950 °C. This result is encouraging for future endeavors of attaining acceptable modulus of carbon fiber from lignin given suitable modifications to the chemistry and structure of lignin. The results of this research contribute to an improved understanding of the carbonization mechanism of the key cellulose and lignin components of biomass materials. [ABSTRACT FROM AUTHOR]

An introduction to an article published in the journal about the topic of successful smoking cessation efforts among maternal smokers with low incomes, and the role of the federal program Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).

The results obtained from a drying experiment using infrared heating are compared to those obtained from an analytical model based on correlations for the mass transfer coefficients, which are commonly used to obtain evaporation rates for drying applications. It was shown that the mass transfer coefficients calculated by natural convection correlations are approximately ten times lower than those measured under infrared (IR) exposure. In an attempt to explain this discrepancy, which has been also observed in other studies and explained on the basis of thermal radiation effects, optical properties of the solvent are presented and the implications of the IR and near infrared (NIR) spectrum on the thermal radiation effects and ensuing evaporation rates are discussed. The results show that the correlation for mass transfer coefficient has to take into account the IR radiation temperature and the surface emissivity. This study provides important evaporation data on mass flux and mass transfer coefficients, which cannot be predicted using traditional correlations, for the design of IR assisted drying systems. [ABSTRACT FROM AUTHOR]

Abstract Microstructural changes induced by neutron irradiation of superfine grain graphite G347A (Tokai Carbon, Japan) were examined by nitrogen adsorption at 77 K and by three microscopy techniques (SEM, TEM and FIB-SEM tomography). The specimens were irradiated at doses of up to 30 dpa, covering stages before and after the turnaround fluence at three temperatures (300, 450, 750 °C) of their irradiation envelope. The initial graphite densification at low fluences did not produce any detectable effect in the pore size range (<350 nm) measured by gas adsorption. However, graphite irradiated at high fluences, after turnaround, showed severe structural changes. At all three temperatures and high irradiation fluences, gas adsorption revealed significant increase of the volume of narrow mesopores (<5–20 nm) and up to five times increase of BET surface area, both in linear relationship with the relative volume expansion. Analysis of microscopy images showed multiplication of fine macropores (>50 nm) at high irradiation fluences and more structural changes on multiple scales, from nanometers to microns. This work demonstrates the unique ability of gas adsorption techniques to analyze open pores with sizes between sub-nanometer and sub-micron in bulk nuclear graphite, with supporting microscopy results. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Synthetic colorants are widely used globally by different industries for the dyeing process. However, these chemicals pollute the environment and affect human health by causing allergies, hives, dermatitis, and cancer. This study aims to compare the effectiveness of duckweed (Lemna minor) in the removal of the Methylene Blue (MB) and Congo red (CR) dyes at different concentrations (1 mg/L, 5 mg/L, 10 mg/L, and 15 mg/L). Absorbance values were determined at 665 nm for MB and 497 nm for CR after 96 hours. The results show higher removal of MB compared to CR for all concentrations (95.49 % vs. 59.32%, 1 mg/L; 97.24% vs. 39.43%, 5mg/L; 91.30% vs 28.47%, 10mg/L; y 85.42% vs 20.27%, 15mg/L). The removal of MB was observed after 30 min of contact with duckweed, while the removal of CR was observed after 24 hours in all concentrations. [ABSTRACT FROM AUTHOR]

Four grades of nuclear graphite were oxidized in helium with traces of moisture and hydrogen in order to evaluate the effects of slow oxidation by moisture on graphite components in high temperature gas cooled reactors. Kinetic analysis showed that the Langmuir-Hinshelwood (LH) model cannot consistently reproduce all results. In particular, at high temperatures and water partial pressures, oxidation was always faster than the LH model predicts. It was also found empirically that the apparent reaction order for water has a sigmoid-type variation with temperature which follows the integral Boltzmann distribution function. This suggests deviations from the LH model are apparently caused by activation with temperature of graphite reactive sites, which is probably rooted in specific structural and electronic properties of graphite. A semi-global kinetic model was proposed, whereby the classical LH model was modified with a temperature-dependent reaction order for water. This new Boltzmann-enhanced Langmuir-Hinshelwood (BLH) model consistently predicts oxidation rates over large ranges of temperature (800–1100 °C) and partial pressures of water (3–1200 Pa) and hydrogen (0–300 Pa). The BLH model can be used for modeling chronic oxidation of graphite components during life-time operation in high- and very high temperature advanced nuclear reactors. [ABSTRACT FROM AUTHOR]

For the next generation of nuclear reactors, HTGRs specifically, an unlikely air ingress warrants inclusion in the license applications of many international regulators. Much research on oxidation rates of various graphite grades under a number of conditions has been undertaken to address such an event. However, consequences to the reactor result from the microstructural changes to the graphite rather than directly from oxidation. The microstructure is inherent to a graphite's properties and ultimately degradation to the graphite's performance must be determined to establish the safety of reactor design. To understand the oxidation induced microstructural change and its corresponding impact on performance, a thorough understanding of the reaction system is needed. This article provides a thorough review of the graphite-molecular oxygen reaction in terms of kinetics, mass and energy transport, and structural evolution: all three play a significant role in the observed rate of graphite oxidation. These provide the foundations of a microstructurally informed model for the graphite-molecular oxygen reaction system, a model kinetically independent of graphite grade, and capable of describing both the observed and local oxidation rates under a wide range of conditions applicable to air-ingress. [ABSTRACT FROM AUTHOR]

Matrix graphite (MG) with incompletely graphitized binder used in high-temperature gas-cooled reactors (HTGRs) is commonly suspected to exhibit lower oxidation resistance in air. In order to reveal the oxidation performance, the oxidation behavior of newly developed A3-3 MG at the temperature range from 500 to 950°C in air was studied and the effect of oxidation on the compressive strength of oxidized MG specimens was characterized. Results show that temperature has a significant influence on the oxidation behavior of MG. The transition temperature between Regimes I and II is ~700°C and the activation energy (Ea) in Regime I is around 185 kJ/mol, a little lower than that of nuclear graphite, which indicates MG is more vulnerable to oxidation. Oxidation at 550°C causes more damage to compressive strength of MG than oxidation at 900°C. Comparing with the strength of pristine MG specimens, the rate of compressive strength loss is 77.3% after oxidation at 550°C and only 12.5% for oxidation at 900°C. Microstructure images of SEM and porosity measurement by Mercury Porosimetry indicate that the significant compressive strength loss of MG oxidized at 550°C may be attributed to both the uniform pore formation throughout the bulk and the preferential oxidation of the binder. [ABSTRACT FROM AUTHOR]

We report results of vibrational neutron spectroscopy investigation aimed to identify the state of hydrogen adsorbed in ultramicroporous carbon. The mobility of hydrogen confined in carbon pores was probed as a function of temperature and pressure using inelastic neutron scattering, and the molecular translational and rotational motions were studied. At low loading rotation of H2 molecules adsorbed in the smallest carbon pores (-4-5 Å) is severely hindered, suggesting that the interaction between H2 and the host matrix is anisotropic. At higher loading, H2 molecules behave as a nearly free rotor, implying lower anisotropic interactions with adsorption sites. At 77 K where bulk H2 is a gas, deconvolution of elastic/quasielastic signal provide evidence of pressure-dependent fractions of immobile (solid-like) and partially mobile (liquid-like) hydrogen, which correlate with the excess adsorption isotherm at 77 K. Effective H2 density in pores changes from solid-like to liquid-like with increasing pressure at 77 K. Surprisingly, immobile and partially mobile H2 is present even at temperatures as high as -110 K where bulk hydrogen exists only in gas form. [ABSTRACT FROM AUTHOR]

Laser ultrasonic line source methods have been used to study elastic anisotropy in nuclear graphites by measuring shear wave birefringence. Depending on the manufacturing processes used during production, nuclear graphites can exhibit various degrees of material anisotropy related to preferred crystallite orientation and to microcracking. In this study, laser ultrasonic line source measurements of shear wave birefringence on NBG-25 have been performed to assess elastic anisotropy. Laser line sources allow specific polarizations for shear waves to be transmitted – the corresponding wavespeeds can be used to compute bulk, elastic moduli that serve to quantify anisotropy. These modulus values can be interpreted using physical property models based on orientation distribution coefficients and microcrack-modified, single crystal moduli to represent the combined effects of crystallite orientation and microcracking on material anisotropy. Ultrasonic results are compared to and contrasted with measurements of anisotropy based on the coefficient of thermal expansion to show the relationship of results from these techniques. [ABSTRACT FROM AUTHOR]

Cancer is a complex and heterogeneous genetic disease. Different mutations and dysregulated molecular mechanisms alter the pathways that lead to cell proliferation. In this paper, we explore a method which classifies genes into oncogenes (ONGs) and tumor suppressors. We optimize this method to identify specific (ONGs) and tumor suppressors for breast cancer, lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC) and colon adenocarcinoma (COAD), using data from the cancer genome atlas (TCGA). A set of genes were previously classified as ONGs and tumor suppressors across multiple cancer types (Science 2013). Each gene was assigned an ONG score and a tumor suppressor score based on the frequency of its driver mutations across all variants from the catalogue of somatic mutations in cancer (COSMIC). We evaluate and optimize this approach within different cancer types from TCGA. We are able to determine known driver genes for each of the four cancer types. After establishing the baseline parameters for each cancer type, we identify new driver genes for each cancer type, and the molecular pathways that are highly affected by them. Our methodology is general and can be applied to different cancer subtypes to identify specific driver genes and improve personalized therapy. [ABSTRACT FROM AUTHOR]

Thermal oxidation of nuclear graphite components is highly undesirable because it can cause structural and property degradation that negatively affect a reactor's intended operation. In this work, the body of knowledge of nuclear graphite oxidation is highlighted, including when O 2 , H 2 O, and/or CO 2 are the oxidant. Oxidation conditions relevant to high-temperature gas-cooled reactors (i.e., when oxidation could occur either as an acute or chronic phenomenon) are emphasized. The objective is to summarize graphite oxidation data in a practical and accessible way to inform future research and regulatory requirements. Although each grade of nuclear graphite is different, the oxidation mechanism has underlying commonalities. Although oxidation behavior is grade dependent, the general temperature dependence is well described by a sequence of elementary steps which become rate limiting. Because the regime transition temperature depends on sample microstructure, size, and oxidant supply rate, extrapolating results beyond the experimental range should be done cautiously. Gravimetric oxidation rate measurements generally replicate well. However, caution must be exercised when rates are estimated by other methods or for samples that deviate significantly in size. Air oxidation data for IG-110, NBG-18, and PCEA graphite is critically reviewed to emphasize this point. Despite the amount of experimental data, gaps remain. Sample size and shape effects are not fully explained. Data on the oxidant penetration depth are insufficient. Analytical assessments demonstrate that lower temperature oxidation does not necessarily imply that oxidation is uniform throughout the bulk. Oxidation occurs faster at higher temperature but is more localized to the exposed surface. Paradoxically, at equal mass loss percentage, low temperature oxidation leads to greater property degradation than at high temperature. The isolated effect of oxidation is important; however, a gap remains in the systematic understanding of any potential effect of neutron irradiation on graphite structure and reactivity. [ABSTRACT FROM AUTHOR]

Urban green infrastructure is considered to be a key element in improving quality of life and creating an appropriate framework for sustainable cities. The most used quantitative indicator to assess urban green infrastructure is urban green space (UGS) per capita. This papeŕs aim is to analyze whether UGS is a valuable target to achieve cities’ sustainability goals. We used Romania as a case study, which should meet the target of 26 m 2 of UGS per inhabitants in all cities. Aerial images were used to extract the surface of the UGS categories for a sample of 38 cities in Romania. We compared our data with three other databases (National Institute of Statistics, Environmental Protection Agencies and Urban Atlas) to check for differences. To understand the contribution of geographic and socio-economic factors to the dynamic of the UGS per capita in Romania’s cities, we used a multiple linear regression. To identify differences between cities in terms of their proportions of UGS, multiple correspondence analysis was performed. We found significant differences between the surface of UGS reported by the administrative offices and that resulting from the spatial analysis. The process of reporting UGS data currently has methodological and perspective shortcomings. Moreover, the density of the built-up space, the proximity to major transport infrastructure, the cities’ founding period and the geomorphology criteria are important predictors for the UGS. The target of 26 m 2 of green area per inhabitant in all Romanian cities is not feasible and it should consider the cities’ characteristics, if you want to achieve sustainability goals. Urban green planning should focus more on the development of urban green infrastructure models that are adapted to each type of urban area. [ABSTRACT FROM AUTHOR]

Sleep disturbances overthrow breast cancer patients' eating behavior, aggravating sarcopenic obesity causes like insulin, leptin and dopamine resistance, thus increasing recurrence and mortality risks. Seeking fat loss sollutions for sarcopenic obesity in ER+ breast cancer patients with sleep disturbances, we randomized 50 - of which 16 were depressive - to follow a high protein diet (D) or the diet and sleep journal interventions (D+SJ). Patients ate only when hungry foods naturally high in protein, calcium, omega-3, pre- and probiotics, and were asked to write a daily food journal. Half of the patients were asked to write a 7-day Kalionka Institute type sleep journal - containing questions about the time it took them to fall asleep, number of awakenings during the night, how much they slept, how much they stayed in bed, and self-perceived sleep quality. After writing the sleep journal, we asked patients to follow set sleeping and wake up hours calculated based on their SJ answers, and to not sleep during the day. After 8 weeks we remeasured body composition with a muli-frequency bioelectrical impedance scale. 8 patients from the D+SJ group asked to leave the study, 5 being depressive. D group lost 2.31±2.86% body fat (p=0.001), and 0.76±1.16% visceral fat (p=0.001); with no fat loss difference between patients with or without depression. Depressive patients did not obtain statistically significance for weight loss. D+SJ group improved sleep quality and lost 2.16±2.35% body fat (p=0.002), and 0.86±1.24% visceral fat (p=0.005). Depressive patients didn't obtain statistically significant results neither for fat, nor for weight loss - maybe because of the overtirying effect of the SJ intervention. So, both D and D+SJ interventions improve breast cancer patients' body composition despite sleep disturbances, but only non-depressive patients also lose weight. And SJ intervention improves sleep quality in patients without depression, decreasing weight regain risk. [ABSTRACT FROM AUTHOR]

After diagnosis, many breast cancer patients start consuming high quantities of beetroot and carrot juice, in the hope of improving the outcome of their treatment. However, these foods are very high in nitrate, which can competitively inhibit the uptake of iodine by the thyroid, potentially leading to hypothyroidism or thyroid nodules. We applied a nitrate and iodine food frequency questionnare (asking about dairy, fish, seafood and iodized salt for iodine intake and spinach, carrots, beetroot, lettuce and arugula for nitrate intake) to 353 ER+/PR±/HER2-luminal A and B breast cancer patients during antiestrogenic treatment. We excluded patients with a thyroid disease diagnosis prior to the cancer diagnosis, smokers, ex-smokers and those with renal disease or bipolar disorder. The only correlations found between dietary intake of iodine and nitrate and the incidence of de novo thyroid nodules were: decreased risk for a daily intake of minimum 250ml dairy; and increased risk for daily intakes of over 200g spinach, 250g carrots or 250g beetroot. The correlations between dietary intake of nitrate and the incidence of de novo hypothyroidism were: decreased risk for a daily intake of iodized salt 2.5g and minimum of 100g fish or 250ml dairy; and increased risk for daily intakes of over 250g carrots or 250g beetroot. The results of this study support the hypothesis that the increased intake of nitrate-rich foods - particularly beetroot and carrot juice - is a risk factor for de novo hypothyroidism or thyroid nodules, after a breast cancer diagnosis. [ABSTRACT FROM AUTHOR]

Sleep disturbances overthrow breast cancer patients' eating behavior, aggravating sarcopenic obesity causes like insulin, leptin and dopamine resistance, thus increasing recurrence and mortality risks. Seeking fat loss sollutions for sarcopenic obesity in ER+ breast cancer patients with sleep disturbances, we randomized 50 - of which 16 were depressive - to follow a high protein diet (D) or the diet and sleep journal interventions (D+SJ). Patients ate only when hungry foods naturally high in protein, calcium, omega-3, pre- and probiotics, and were asked to write a daily food journal. Half of the patients were asked to write a 7-day Kalionka Institute type sleep journal - containing questions about the time it took them to fall asleep, number of awakenings during the night, how much they slept, how much they stayed in bed, and self-perceived sleep quality. After writing the sleep journal, we asked patients to follow set sleeping and wake up hours calculated based on their SJ answers, and to not sleep during the day. After 8 weeks we remeasured body composition with a muli-frequency bioelectrical impedance scale. 8 patients from the D+SJ group asked to leave the study, 5 being depressive. D group lost 2.31±2.86% body fat (p=0.001), and 0.76±1.16% visceral fat (p=0.001); with no fat loss difference between patients with or without depression. Depressive patients did not obtain statistically significance for weight loss. D+SJ group improved sleep quality and lost 2.16±2.35% body fat (p=0.002), and 0.86±1.24% visceral fat (p=0.005). Depressive patients didn't obtain statistically significant results neither for fat, nor for weight loss - maybe because of the overtirying effect of the SJ intervention. So, both D and D+SJ interventions improve breast cancer patients' body composition despite sleep disturbances, but only non-depressive patients also lose weight. And SJ intervention improves sleep quality in patients without depression, decreasing weight regain risk. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To evaluate whether participation in a statewide enhanced prenatal and postnatal care program, the Maternal Infant Health Program (MIHP), reduced infant mortality risk. METHODS: Data included birth and death records, Medicaid claims, and program participation. The study population consisted of Medicaid-insured singleton infants born between January 1, 2009, and December 31, 2012, in Michigan (n = 248 059). The MIHP participants were propensity score-matched with nonparticipants based on demographics, previous pregnancies, socioeconomic status, and chronic disease. Infant mortality, neonatal mortality, and postneonatal mortality analyses were presented by race. RESULTS: Infants with any MIHP participation had reduced odds of death in the first year of life compared with matched nonparticipants [odds ratio [OR] 0.73, 95% confidence interval [CI] 0.63-0.84). Infant death odds were reduced both among black infants (OR 0.71, 95% CI 0.58-0.87) and infants of other races (OR 0.74, 95% CI 0.61-0.91). Neonatal death (OR 0.70, 95% CI 0.57-0.86) and postneonatal death odds (OR 0.78, 95% CI 0.63-0.96) were also reduced. Enrollment and screening in MIHP by the end of the second pregnancy trimester and at least 3 additional prenatal MIHP contacts reduced infant mortality odds further (OR 0.70, 95% CI 0.58-0.85; neonatal: OR 0.67, 95% CI 0.51-0.89; postneonatal: OR 0.74, 95% CI 0.56-0.98). CONCLUSIONS: A state Medicaid-sponsored population-based home-visitation program can be a successful approach to reduce mortality risk in a diverse, disadvantaged population. A likely mechanism is the reduction in the risk of adverse birth outcomes, consistent with previous findings on the effects of the program. [ABSTRACT FROM AUTHOR]

Objective To explore preferences in the management of patients with newly diagnosed high-risk prostate cancer ( PCa) among urologists in Europe through a web-based survey. Materials and Methods A web-based survey was conducted between 15 August and 15 September 2013 by members of the Prostate Cancer Working Group of the Young Academic Urologists Working Party of the European Association of Urology ( EAU). A specific, 29-item multiple-choice questionnaire covering the whole spectrum of diagnosis, staging and treatment of high-risk PCa was e-mailed to all urologists included in the mailing list of EAU members. Europe was divided into four geographical regions: Central- Eastern Europe ( CEE), Northern Europe ( NE), Southern Europe ( SE) and Western Europe ( WE). Descriptive statistics were used. Differences among sample segments were obtained from a z-test compared with the total sample. Results Of the 12 850 invited EAU members, 585 urologists practising in Europe completed the survey. High-risk PCa was defined as serum PSA ≥20 ng/mL or clinical stage ≥ T3 or biopsy Gleason score ≥ 8 by 67% of responders, without significant geographical variations. The preferred single-imaging examinations for staging were bone scan (74%, 81% in WE and 70% in SE; P = 0.02 for both), magnetic resonance imaging (53%, 72% in WE and 40% in SE; P = 0.02 and P = 0.01, respectively) and computed tomography (45%, 60% in SE and 23% in WE; P = 0.01 for both). Pre-treatment predictive tools were routinely used by 62% of the urologists, without significant geographical variations. The preferred treatment was radical prostatectomy as the initial step of a multiple-treatment approach (60%, 40% in NE and 70% in CEE; P = 0.02 and P < 0.01, respectively), followed by external beam radiation therapy with androgen deprivation therapy (29%, 45% in NE and 20% in CEE; P = 0.01 and P = 0.02, respectively), and radical prostatectomy as monotherapy (4%, 7% in WE; P = 0.04). When surgery was performed, the open retropubic approach was the most popular (58%, 74% in CEE, 37% in NE; P < 0.01 for both). Pelvic lymph node dissection was performed by 96% of urologists, equally split between a standard and extended template. There was no consensus on the definition of disease recurrence after primary treatment, and much heterogeneity in the administration of adjuvant and salvage treatments. Conclusion With the limitation of a low response rate, the present study is the first survey evaluating preferences in the management of high-risk PCa among urologists in Europe. Although the definition of high-risk PCa was fairly uniform, wide variations in patterns of primary and adjuvant/salvage treatments were observed. These differences might translate into variations in quality of care with a possible impact on ultimate oncological outcome. [ABSTRACT FROM AUTHOR]

Accelerated oxidation tests were performed to determine kinetic parameters of the chronic oxidation reaction (i.e. slow, continuous, and persistent) of PCEA graphite in contact with helium coolant containing low moisture concentrations in high temperature gas-cooled reactors. To the authors' knowledge such a study has not been done since the detailed analysis of reaction of H-451 graphite with steam (Velasquez, Hightower, Burnette, 1978). Since that H-451 graphite is now unavailable, it is urgently needed to characterize chronic oxidation behavior of new graphite grades that are being considered for use in gas-cooled reactors. The Langmuir-Hinshelwood mechanism of carbon oxidation by water results in a non-linear reaction rate expression, with at least six different parameters. They were determined in accelerated oxidation experiments that covered a large range of temperatures (800-1100 °C), and partial pressures of water (15-850 Pa) and hydrogen (30-150 Pa) and used graphite specimens thin enough (4 mm) in order to avoid diffusion effects. Data analysis employed a statistical method based on multiple likelihood estimation of parameters and simultaneous fitting of non-linear equations. The results show significant material-specific differences between graphite grades PCEA and H-451 which were attributed to microstructural dissimilarity between the two materials. It is concluded that kinetic data cannot be transferred from one graphite grade to another. [ABSTRACT FROM AUTHOR]

Smoking during pregnancy is causally associated with reduced birth weight and is strongly related to preterm birth. Smoking cessation in early pregnancy seems to reduce these risks, although the research evidence is limited. In a sample of Romanian women, differences in birth outcomes were assessed between non-smokers and women who continued to smoke during pregnancy and non-smokers and women who stopped smoking when they found out about the pregnancy. Pregnant women were recruited in two urban clinics (N = 474). A baseline questionnaire collected information on their smoking status, depressive symptoms, stress, demographics, and other characteristics at recruitment. The women reported the newborn weight and birth term by phone in the first weeks following birth. Descriptive statistics and multivariate regressions were used to analyze the relationship between smoking status during pregnancy and birth outcomes. Over 61% (N = 290) women were non-smokers, 15% (N = 72) smoked during pregnancy, and 24% (N = 112) quit smoking when they found out about the pregnancy. Compared to non-smokers, continuous smokers delivered babies 165 grams lighter (95% CI -313, -17). Women who stopped smoking when they ascertained the pregnancy had higher odds of delivering a newborn who was small for gestational age compared to non-smokers (OR = 2.16, 95% CI 1.05, 4.43). Elevated maternal stress was associated with reduced birth weight (-113 grams, 95% CI -213, -11), and higher odds of a preterm birth (OR = 2.8, 95% CI 1.17, 6.76). In a predominantly urban sample of Romanian women, continuous maternal smoking during pregnancy was a risk factor for restricted foetal growth. Smoking cessation when the pregnancy was ascertained did not seem to reduce this risk. Smoking prevention efforts should therefore begin before pregnancy and should integrate psychological components, addressing maternal stress in particular. [ABSTRACT FROM AUTHOR]

Abstract: Natural graphite powders were subjected to a series of thermal treatments to improve the anode irreversible capacity loss and capacity retention during long-term cycling of lithium-ion batteries. A baseline thermal treatment in inert Ar or N2 atmosphere was compared to cases with a proprietary additive to the furnace gas. This additive substantially altered the surface chemistry of the uncoated natural graphite powders and resulted in significantly improved long-term cycling performance of the lithium ion batteries over the commercial, carbon-coated natural graphite baseline. Different heat-treatment temperatures were investigated ranging from 950 to 2900°C to achieve the desired long-term cycling performance with a significantly reduced thermal budget. A detailed summary of the characterization data is also presented, which includes X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, and temperature-programmed desorption-mass spectroscopy. Characterization data was correlated to the observed capacity fade improvements over the course of long-term cycling at high charge–discharge rates in full lithium-ion cells. It is believed that the long-term performance improvements are a result of forming a more stable solid electrolyte interface (SEI) layer on the anode graphite surfaces, which is directly related to the surface chemistry modifications imparted by the proprietary gas environment during thermal treatment. [Copyright &y& Elsevier]

Background: The Michigan Maternal and Infant Health Program (MIHP) is a population-based home-visitation program providing care coordination, referrals, and visits based on a plan of care. MIHP is available to all Medicaid-eligible pregnant women and infants aged ≤1 year in Michigan. Purpose: To assess the effects of MIHP participation on maternal and infant healthcare utilization. Methods: Propensity-score matching methods were used to assess differences in healthcare utilization between MIHP participants and nonparticipants using 2009—2010 Medicaid claims and administrative data obtained from the Michigan Department of Community Health. Data were analyzed between October 2011 and March 2013. Results: MIHP participants had higher odds of receiving any prenatal care compared to matched women not participating in MIHP (OR=2.94, 95% CI=2.43, 3.60) and higher odds of receiving adequate prenatal care (OR=1.06, 95% CI=1.01, 1.11). MIHP participants had higher odds of receiving an appropriately timed postnatal visit (OR=1.50, 95% CI=1.43, 1.57). Infants participating in MIHP had higher odds of receiving any well-child visits over the first year of life (OR=1.70, 95% CI=1.51, 1.93) and higher odds of receiving the appropriate number of well-child visits over their first year of life (OR=1.47, 95% CI=1.35, 1.60) compared to matched nonparticipant infants. Conclusions: The results from Michigan provide strong evidence for the effectiveness of a Medicaid-sponsored population-based home-visitation program in improving maternal prenatal and postnatal care and infant care. This evidence is important to consider as the federal healthcare reform is implemented and states are making decisions on the expansion of the Medicaid program. [ABSTRACT FROM AUTHOR]

Quasielastic neutron scattering of H2 and D2 in the same nanoporous carbon at 10-40 K demonstrates extreme quantum sieving, with D2 diffusing up to 76 times faster. D2 also shows liquidlike diffusion while H2 exhibits Chudley-Elliott jump diffusion, evidence of their different relationships with the local lattice of adsorption sites due to quantum effects on intermolecular interactions. The onset of diffusion occurs at 22-25 K for H2and 10-13 K for D2. At these temperatures, H2 and D2 have identical thermal de Broglie wavelengths that correlate with the dominant pore size. [ABSTRACT FROM AUTHOR]

Abstract: The oxidation-induced porosity development in nuclear graphite has great effect on its mechanical behavior, thus it is very important to understand the pore structure development of nuclear graphite during oxidation. This paper reports on the oxidation kinetics of grade IG-110 nuclear graphite and the porosity development in oxidized samples. The distribution of the oxidized layer in IG-110 specimens oxidized at 600–750°C was studied using optical microscopy coupled with automated image analysis technique, and the mechanism of porosity development was determined. The thickness of oxidized layer decreased with the oxidation temperature but was independent of the weight loss level. Oxidation caused consumption of graphite structure and development of porosity, which was initiated from the binder phase. Statistical analysis indicated that generation and growth of pores was dominant at low temperatures, while merging and collapse of pores was the main effect at high temperatures. Compared with medium-grained PCEA graphite, the fine-grained IG-110 graphite demonstrates deeper penetration of the oxidant because of its higher pore density and greater porosity. [Copyright &y& Elsevier]

Abstract: Oxidation resistance in air of three grades of nuclear graphite with different structures was compared using a standard thermogravimetric method. Differences in the oxidation behavior have been identified with respect to both (i) the rate of oxidation in identical conditions and the derived apparent activation energy and pre-exponential factor and (ii) the penetration depth of the oxidant and the development of the oxidized layer. These differences were ascribed to structural differences between the three graphite grades, in particular the grain size and shape of the graphite filler, and the associated textural properties, such as total BET surface area and porosity distribution in the un-oxidized material. It was also found that the amount of strongly bonded surface oxygen complexes measured by thermodesorption significantly exceeds the amount afforded by the low BET surface area, and therefore low temperature oxygen chemisorption is not a reliable method for determining the amount of surface sites (re)active during air oxidation. The relationship between nuclear graphite microstructure and its oxidation resistance demonstrated in this work underlines the importance of performing comprehensive oxidation characterization studies of the new grades of nuclear graphite considered as candidates for very high temperature gas-cooled reactors. [Copyright &y& Elsevier]

Abstract: Objectives: To fill the gap in assessing nicotine dependence during pregnancy in an unexplored population in Central and Eastern Europe and to analyze the associations of maternal characteristics and prenatal risk factors with moderate-heavy nicotine dependence among pregnant smokers. Study design: A questionnaire was applied to pregnant smokers in Romania to assess nicotine dependence and other related risks poorly documented in Central and Eastern Europe. The response rate was >80% and the valid sample included 137 pregnant smokers. Descriptive statistics and logistic regressions were used to assess nicotine dependence and to analyze the associations of maternal characteristic and prenatal risk factors with moderate-heavy nicotine dependence. Results: Approximately 43% of the pregnant smokers in our sample (59 of 137) had moderate to heavy nicotine dependence. Depressive symptoms were associated with moderate-heavy nicotine dependence among pregnant smokers (OR=3.07, p <0.05). Women carrying an unwanted pregnancy had higher odds of moderate-heavy nicotine dependence (OR=2.59, p <0.05) compared to other pregnant women. High stress, lack of social support, and socioeconomic status were not associated with nicotine dependence. Conclusions: A large proportion of women had moderate-heavy nicotine dependence in a sample of Romanian pregnant smokers. The more dependent pregnant smokers were more likely to have depressive symptoms. Prenatal care should include brief nicotine dependence assessments and mental health screening and referrals for pregnant women who smoke. Special and intensive efforts, including psychosocial components, may be needed for the nicotine dependent pregnant smokers. [Copyright &y& Elsevier]

Abstract: The use of architectures based on services and multi-agent systems has become an increasingly important part of the solution set used for the development of distributed systems. Nevertheless, these models pose a variety of problems with regards to security. This article presents the Adaptive Intrusion Detection Multi-agent System (AIDeMaS), a mechanism that has been designed to detect and block malicious SOAP messages within distributed systems built by service based architectures. AIDeMaS has been implemented as part of FUSION@, a multi-agent architecture that facilitates the integration of distributed services and applications to optimize the construction of highly-dynamic multi-agent systems. One of the main features of AIDeMaS is that is employs case-based reasoning mechanisms, which provide it with great learning and adaptation capabilities that can be used for classifying SOAP messages. This research presents a case study that uses the ALZ-MAS system, a multi-agent system built around FUSION@, in order to confirm the effectiveness of AIDeMaS. The preliminary results are presented in this paper. [Copyright &y& Elsevier]

Abstract: Owing to several disadvantages of traditional hard template based synthesis, soft-template or self-assembly was adopted to synthesize mesoporous carbon. In this work, we have introduced hexaphenol as a new and large organic precursor for the synthesis of mesoporous carbon by self-assembly with Pluronic P123 as structure dictating agent. The resultant mesoporous carbon is bimodal in nature with median pore widths of 29 and 45Å and BET surface area of 312m2/g. Unlike previously synthesized mesoporous carbon, this carbon possesses negligible micropore volume. This mesoporous carbon is very suitable candidate for several applications including membrane separation, chemical sensor or selective sorption of larger molecules. [Copyright &y& Elsevier]

Background: Smoking during pregnancy is one of the most modifiable risk factor for poor birth outcomes. This study assesses the prevalence and correlates of smoking during pregnancy. Methods: A questionnaire was applied to pregnant women in two urban clinics in Romania to assess smoking prevalence, attitudes and knowledge about smoking, and other risks poorly documented in Romania, such as depressive symptoms, stress and social support. The response rate was >80% and the valid sample comprised of 916 women. Descriptive statistics and logistic regressions were used to estimate the prevalence of smoking and other risk factors and to identify correlates of smoking during pregnancy. Results: Approximately 15% of the women continued smoking during pregnancy, and 26% of all women said they smoked prior to pregnancy, but quit upon finding out they were pregnant. Depressive symptoms and stress were not associated with smoking during pregnancy. Women with no social support had higher odds of continued smoking vs. non-smoking (OR = 2.3, P < 0.01), and vs. quitting (OR = 2.3, P < 0.05). Roma women had 5.2 times the odds (P < 0.01) of continued smoking vs. non-smoking. Lack of awareness about the benefits of quitting smoking and about the risks of smoking light cigarettes were associated with continued smoking during pregnancy. Conclusions: Smoking was common in a sample of Romanian pregnant women. Smoking cessation programs in Romania should include components to raise the awareness about the risks of smoking during pregnancy and the benefits of quitting at any time during pregnancy. More targeted interventions are needed in Roma communities. [ABSTRACT FROM AUTHOR]

Abstract: Quasi-elastic neutron scattering was used for characterization of dynamics of molecular hydrogen confined in narrow nanopores of two activated carbon materials: a carbon derived from polyfurfuryl alcohol and an ultramicroporous carbon. Fast, but incomplete ortho–para conversion was observed at 10K, suggesting that scattering originates from the fraction of unconverted ortho isomer which is rotation-hindered because of confinement in nanopores. Hydrogen molecules entrapped in narrow nanopores (<7Å) were immobile below 22–25K. Mobility increased rapidly with temperature above this threshold, which is higher than the melting point of bulk hydrogen (13.9K). Diffusion obeyed fixed-jump length mechanism, indistinguishable between 2D and 3D processes. Thermal activation of diffusion was characterized between ∼22 and 37K, and structure-dependent differences were found between the two carbons. Activation energy of diffusion was higher than that of bulk solid hydrogen. Classical notions of liquid and solid do not longer apply for H2 confined in narrow nanopores. [Copyright &y& Elsevier]

Abstract: Palladium-modified activated carbon fibers (Pd-ACF) were synthesized by melt-spinning, carbonization and activation of an isotropic pitch carbon precursor premixed with an organometallic Pd compound. The hydrogen uptake at 25°C and 20bar on Pd-ACF exceeded the expected capacity based solely on Pd hydride formation and hydrogen physisorption on the microporous carbon support. Aberration-corrected scanning transmission electron microscopy (STEM) with sub-Ångstrom spatial resolution provided unambiguous identification of isolated Pd atoms occurring in the carbon matrix that coexist with larger Pd particles. First principles calculations revealed that each single Pd atom can form Kubas-type complexes by binding up to three H2 molecules in the pressure range of adsorption measurements. Based on Pd atom concentration determined from STEM images, the contribution of various mechanisms to the excess hydrogen uptake measured experimentally was evaluated. With consideration of Kubas binding as a viable mechanism (along with hydride formation and physisorption to carbon support) the role of hydrogen spillover in this system may be smaller than previously thought. [Copyright &y& Elsevier]

Abstract: During the last years the use of Web Service-based applications has notably increased. However, the security has not evolved proportionally, which makes these applications vulnerable and objective of attacks. One of the most common attacks requiring novel solutions is the denial of service attack (DoS), caused for the modifications introduced in the XML of the SOAP messages. The specifications of existing security standards do not focus on this type of attack. This article presents the S-MAS architecture as a novel adaptive approach for dealing with DoS attacks in Web Service environments, which represents an alternative to the existing centralized solutions. S-MAS proposes a distributed hierarchical multi-agent architecture that implements a classification mechanism in two phases. The main benefits of the approach are the distributed capabilities of the multi-agent systems and the self-adaption ability to the changes that occur in the patterns of attack. A prototype of the architecture was developed and the results obtained are presented in this study. [ABSTRACT FROM AUTHOR]

Abstract: The effect of mixing chemically-activated ultramicroporous carbon (UMC) with Pd nanopowder is investigated. Results show that Pd addition doubles the rate of hydrogen uptake, but does not enhance the hydrogen capacity or improve desorption kinetics. The effect of Pd on the rate of hydrogen adsorption supports the existence of the hydrogen spillover mechanism in the Pd – UMC system. [Copyright &y& Elsevier]

Abstract: Hydrogen adsorption on ultramicroporous carbon was investigated at near-ambient temperatures using volumetric and gravimetric methods. The results showed that the main process, physisorption, is accompanied by a slow process of different nature, that causes slow uptake at high pressures and hysteresis on desorption. The combined result is unusually high levels of hydrogen uptake at near-ambient temperatures and pressures (e.g. up to 0.8wt.% at 25°C and 2MPa). The heat of adsorption corresponding to the slow process leading to high uptake (17–20kJ/mol) is higher than usually reported for carbon materials; the adsorption kinetics is slow, and the isotherms exhibit pronounced hysteresis. These unusual properties were attributed to contributions from polarization-enhanced physisorption induced by traces of alkali metals residual from chemical activation. The results support the hypothesis that polarization-induced physisorption in high surface area carbons modified with traces of alkali metal ions is an alternate route for increasing the hydrogen storage capacity of carbon adsorbents. [Copyright &y& Elsevier]

Abstract: Background: Love Canal, in Niagara Falls, NY is among the earliest and most significant hazardous waste sites in the USA, but no study has ever measured chemical body burdens in nearby residents to document that human exposure occurred. This study measured concentrations of selected organochlorines and chlorinated benzenes in archived serum samples collected from former Love Canal residents. Methods: We analyzed serum samples collected from 373 former residents in 1978–1979 for compounds disposed of at Love Canal, and we compared their concentrations according to surrogate indicators of exposure such as residential proximity, adjusting for potential confounders. Results: Three compounds were detectable in the serum of most participants: 1,2,4-trichlorobenzene (1,2,4-TCB), β-hexachlorocyclohexane (β-HCH) and 1,2-dichlorobenzene (1,2-DCB). Concentrations of 1,2,4-TCB and 1,2-DCB were 2–14 times greater among persons who at the time their blood was collected lived closest to the Canal compared to those living further away. We found no consistent trends for β-HCH with respect to any exposure definition. Conclusions: These results provide evidence that residential proximity to Love Canal contributed to the body burden of certain contaminants, and helps validate the use of surrogate exposure measures in health effect studies. Further surveillance of the Love Canal cohort is warranted. [Copyright &y& Elsevier]

Medicaid insures an estimated 43% of all births in Michigan and provides additional funding for enhanced prenatal services (EPS). The objectives of this study are to report on the (1) use of statewide administrative data to examine risk characteristics and EPS enrollment of Medicaid-insured pregnant women in Michigan; and (2) presence and extent of a broad range of risk factors in a sample of EPS participants in Michigan, using a newly developed two-tier, risk screener and assessment tool. This study uses Vital Records, Medicaid and other data to describe EPS participation by maternal risks in the statewide population of Medicaid-insured pregnant women (54,582 in the fiscal year 2005). The screener study data is a convenience sample of 2,203 women screened between February 2005 and October 2007. The administrative data indicates that 26% of Medicaid-eligible pregnant women had EPS contact. Most women with health behavior risks, such as smoking and drug use, had no contact with EPS (68–72%). Approximately 58% of all Medicaid-insured women had zero to two co-occurring risks, while 42% had three or more of the analyzed risks. Among screened women who smoke, 9% smoked more than a pack a day. Approximately 34% of women with a depression screen scored in the moderately or severely depressed range. The results of this study suggest great opportunity for EPS enhancement by improving the capacity to identify and engage women with modifiable risks, match interventions to specific health problems, and deliver services at an intensity warranted by the risk level. [ABSTRACT FROM AUTHOR]

The strong correlation between the density and the physical and mechanical properties of graphite suggests that the method of nondestructive density evaluation could be developed into a characterization technique of great value for the overall improvement of the safety of graphite moderator reactors. In this study, the oxidation-induced density changes in nuclear graphite for very high temperature reactor were determined by a conventional destructive bulk density measurement method (BM) and by a new nondestructive method based on acoustic microscopy and image processing (AM). The results were compared in order to validate the applicability of the latter method. For a direct comparison of the results from both measurements, two specimens were prepared from a cylindrical graphite sample (1 in. diameter and 1 in. height, oxidized to 10% weight loss at 973 K in air for 5 h). The specimens were used for characterization by BM and AM methods, respectively. The results show that, even with a large standard deviation of the AM, the density changing trend from both methods appeared the same. The present observation may be attributed to the fact that AM images reflect characteristic density changes of the graphite sample through the acoustic impedance changes. This study demonstrates the possibility of using AM as a nondestructive technique for the evaluation of density changes in graphite when a database is prepared through a systematic series of experiments. [ABSTRACT FROM AUTHOR]

Mass spectrometry (MS) is the most comprehensive and versatile tool in large-scale proteomics. In this review, we dissect the overall framework of the MS experiment into its key components. We discuss the fundamentals of proteomic analyses as well as recent developments in the areas of separation methods, instrumentation, and overall experimental design. We highlight both the inherent strengths and limitations of protein MS and offer a rough guide for selecting an experimental design based on the goals of the analysis. We emphasize the versatility of the Orbitrap, a novel mass analyzer that features high resolution (up to 150,000), high mass accuracy (2-5 ppm), a mass-to-charge range of 6000, and a dynamic range greater than 10³. High mass accuracy of the Orbitrap expands the arsenal of the data acquisition and analysis approaches compared with a low-resolution instrument. We discuss various chromatographic techniques, including multidimensional separation and ultra-performance liquid chromatography. Multidimensional protein identification technology (MudPIT) involves a continuum sample preparation, orthogonal separations, and MS and software solutions. We discuss several aspects of MudPIT applications to quantitative phosphoproteomics. MudPIT application to large-scale analysis of phosphoproteins includes (a) a fractionation procedure for motif-specific enrichment of phosphopeptides, (b) development of informatics tools for interrogation and validation of shotgun phosphopeptide data, and (c) in-depth data analysis for simultaneous determination of protein expression and phosphorylation levels, analog to western blot measurements. We illustrate MudPIT application to quantitative phosphoproteomics of the beta adrenergic pathway. We discuss several biological discoveries made via mass spectrometry pipelines with a focus on cell signaling proteomics. [ABSTRACT FROM AUTHOR]

Abstract: The efforts for designing a meaningful and acceptable standard test method for characterization of kinetic parameters of air oxidation of graphite helped identify several practical issues that must be considered for the development of such a test. Using standard size (and shape) specimens, large enough in size to accommodate the inherent local microstructure differences between graphite samples, resulted in non-uniform oxidation profiles and preferential binder oxidation; this was not expected based on the linearity of Arrhenius plots and the (large) values of activation energy. It was found that the transition between the regimes 1 and 2 of graphite oxidation occurs gradually, depending both on the oxidation temperature and rate of oxygen supply. Nevertheless, measuring oxidation rates obtained on standard size samples provides a basis for a meaningful comparison among materials, which may serve as much needed information for predictive models. [Copyright &y& Elsevier]

Abstract: Fabrication of uranium oxicarbide microspheres, a component of TRISO fuel particles for high temperature nuclear power systems, is based on the internal gelation of uranium salts in the presence of carbon black. In order to obtain a high quality product, carbon black should remain dispersed during all phases of the gelation process. In this study, the surface and structural properties of several commercial carbon black materials, and the use of dispersing agents was examined with the goal of finding optimal conditions for stabilizing submicron-sized carbon black dispersions. Traditional methods for stabilizing dispersions, based on the use of dispersing agents, failed to stabilize carbon dispersions against large pH variations, typical for the internal gelation process. An alternate dispersing method was proposed, based on using surface-modified carbons functionalized with strongly ionized surface groups (sodium sulfonate). With a proper choice of surface modifiers, these advanced carbons disperse easily to particles in the range of 0.15–0.20μm and the dispersions remain stable during the conditions of internal gelation. [Copyright &y& Elsevier]

Networks of interacting genes are responsible for generating life's complexity and for mediating how organisms respond to their environment. Thus, a basic understanding of genetic variation in gene networks in natural populations is important for elucidating how changes at the genetic level map to higher levels of biological organization. Here, using the well-characterized phototransduction network in Drosophila, we analyze variation in gene expression within and between two closely related species, Drosophila melanogaster and Drosophila simulans, under different environ- mental conditions. Gene expression levels in the pathway are largely conserved between these two sibling species. For most genes in the network, differences in level of gene expression between species are correlated with degree of polymorphism within species. However, one gene encoding the light-induced ion channel TRPL (transient receptor potential-like) shows an excess of expression divergence relative to polymorphism, suggesting a possible role for natural selection in shaping this expression difference between species. Finally, this difference in TRPL expression likely has significant functional consequences, because it is known that a high level of rhabdomeral TRPL leads to increased sensitivity to dim background light and an increased response to a wider range of light intensities. These results provide a preliminary quantification of variation and divergence of gene expression between species in a known gene network and provide a foundation for a system-level understanding of functional and evolutionary change. [ABSTRACT FROM AUTHOR]

A new family of structures launching the fundamental mode in rectangular waveguides is proposed. Individual or stacked cavity-backed patch antennas radiate into a rectangular waveguide, providing a good matching with a coaxial input over a wide frequency range. The configuration results in a very compact, colinear transition from a standard coaxial connector to a rectangular waveguide. The components have applications as general-purpose coaxial-to-rectangular waveguide transitions and are well suited for low-profile, phased-array antennas. Experimental results confirm the computational estimations of the proposed components' performance. [ABSTRACT FROM AUTHOR]

A consistent strategy for the design of finite array antennas consisting of differently sized radiating elements is discussed. In view of increasing the total bandwidth of the antenna system, while maintaining a low mutual coupling between the elementary radiators, sparse subarrays, operating at adjacent frequency ranges, are interleaved on a common (shared) aperture. The sparse architectures are designed using a combinatorial method that ensures an acceptable behavior in the side-lobes region in conjunction with a narrow beamwidth. The effect of the mutual coupling between identical and differently sized elements is accurately evaluated and is accounted for in predicting the performance of each individual radiator. The concept is illustrated by designing a shared aperture antenna consisting of two interwoven subarrays that jointly cover a fractional bandwidth of 14% in the X-band. Cavity-backed, stacked-patches antennas with coaxial feeding are used as elementary radiators. [ABSTRACT FROM PUBLISHER]