cssi/SciSciGPT-SciSciNet huggingface dataset:
Polyimide aerogels with amide cross-links: A low cost alternative for mechanically strong polymer aerogels

Polyimide aerogels combine high porosity, low thermal conductivity, flexibility, and low density with excellent mechanical properties. However, previously used cross-linkers, such as 1,3,5-triaminophenoxybenzene (TAB), 2,4,6-tris(4-aminophenyl)pyridine (TAPP), or octa(aminophenoxy)silsesquioxane (OAPS), either are not commercially available or are prohibitively expensive. Finding more cost efficient cross-linkers that are commercially available to synthesize these aerogels is crucial for making large scale manufacturing attractive. Herein, we describe an approach to making polyimide aerogels starting with amine capped oligomers that are cross-linked with 1,3,5-benzenetricarbonyl trichloride (BTC). BTC is a lower cost, commercially available alternative to TAB, TAPP, or OAPS. Aerogels made in this way have the same or higher modulus and higher surface area compared to those previously reported with either TAB or OAPS cross-links at the same density. While the cross-link structure is an amide, the thermal s...
N2O and no emissions from poultry litter and urea applications to Bermuda grass

Abstract The objectives of the study were to quantify N2O and NO emissions from poultry litter and urea applications to Bermuda grass (Cynodaon dactylon L.) and examine the seasonal variations in emissions. Soil N2O and NO emissions were measured in a Bermuda grass pasture treated with two sources of poultry litter, composted poultry litter (CPL) and fresh poultry litter (FPL) and urea (URE). Nitrogen (N) was applied to supply 336 kg available N ha-1 in four split applications made during the period from April to August 1995. An automated closed chamber system was employed to monitor N2O and NO emissions. The seasonal N2O emission patterns were characterized by several peaks occurring in phase with intermittent rain events and increasing soil N and organic carbon (C) associated with fertilizer application. The cumulative N2O emissions over the season (May to mid September) from the various treatments were, 3.87 kg N ha-1 from FPL, 2.96 kg N ha-1 from URE, and 1.64 kg N ha-1 from CPL. These seasonal N2O losses accounted for 1.0, 0.73 and 0.32% of the added available N for the, FPL, URE and CPL treatments, respectively. Denitrification was suggested as the primary source of N2O following rain events when inorganic N and C soil concentrations were highest and soil water-filled-pore-space (WFPS) was elevated. Peaks in NO emissions were observed primarily immediately after the addition of N sources. The seasonal NO emissions were smaller and ranged from 1.36 kg N ha-1 for URE, and 0.97 kg N ha-1 for FPL, to 0.47 kg N ha-1 for CPL. The seasonal NO emissions accounted for 0.36, 0.24 and 0.09% of the added N for the URE, FPL, and CPL treatments, respectively.
Memory CD4+ T-cell-mediated protection from lethal coronavirus encephalomyelitis.

The antiviral role of CD4+ T cells in virus-induced pathologies of the central nervous system (CNS) has not been explored extensively. Control of neurotropic mouse hepatitis virus (JHMV) requires the collaboration of CD4+ and CD8+ T cells, with CD8+ T cells providing direct perforin and gamma interferon (IFN-γ)-mediated antiviral activity. To distinguish bystander from direct antiviral contributions of CD4+ T cells in virus clearance and pathology, memory CD4+ T cells purified from wild type (wt), perforin-deficient (PKO), and IFN-γ-deficient (GKO) immune donors were transferred to immunodeficient SCID mice prior to CNS challenge. All three donor CD4+ T-cell populations controlled CNS virus replication at 8 days postinfection, indicating IFN-γ- and perforin-independent antiviral function. Recipients of GKO CD4+ T cells succumbed more rapidly to fatal disease than untreated control infected mice. In contrast, wt and PKO donor CD4+ T cells cleared infectious virus to undetectable levels and protected from fatal disease. Recipients of all CD4+ T-cell populations exhibited demyelination. However, it was more severe in wt CD4+ T-cell recipients. These data support a role of CD4+ T cells in virus clearance and demyelination. Despite substantial IFN-γ-independent antiviral activity, IFN-γ was crucial in providing protection from death. IFN-γ reduced neutrophil accumulation and directed macrophages to white matter but did not ameliorate myelin loss.
Characterization of the dose-response of CYP1B1, CYP1A1, and CYP1A2 in the liver of female Sprague-Dawley rats following chronic exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin.

One of the current knowledge gaps in the evaluation of risk for human exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is the relationship between gene expression induced by TCDDmore complex biological responses such as altered growth, differentiation, and neoplasia. This study investigates the dose-dependent expression of CYP1A1, CYP1A2,CYP1B1 in the livers of female Sprague-Dawley rats chronically exposed to TCDD. Animals were treated biweekly for 30 weeks with daily averaged doses of 0 to 125 ng TCDD/kg/day. Immunoblot analysis showed that protein levels for CYP1B1, CYP1A1, CYP1A2 exhibited a dose-dependent induction by TCDD. However, CYP1A1 and CYP1A2 protein levels were approximately 100-fold higher than CYP1B1, which could not be detected by either immunoblot analysis or immunohistochemistry in the livers of rats treated with TCDD for 30 weeks at a dose-equivalent less than 35.7 ng/kg/day. In control animals, CYP1A1CYP1A2 RNA levels, measured by quantitative RT-PCR, were 1100-15,000-fold higher than that of CYP1B1, respectively. TCDD induced CYP1B1 RNA levels at all doses, although absolute TCDD-induced levels of CYP1A1CYP1A2 at the highest dose (125 ng/kg/day) were more than 40-fold higher than that of CYP1B1. While the liver concentration of TCDD required for half-maximal induction of CYP1A1, CYP1A2,CYP1B1 RNA levels was similar, the shaping parameter (Hill coefficient) of the dose-response curve for CYP1B1 was significantly higher than that for CYP1A1 or CYP1A2. The low level of TCDD-induced CYP1B1 expression in the liver relative to that of the CYP1A1CYP1A2 suggest that, if CYP1B1 is involved in TCDD-induced hepatocarcinogenesis, its endogenous function is likely to be uniquenot overlapping with that of CYP1A1 or CYP1A2.
Hyperglycosylated hCG (invasive trophoblast antigen, ITA) a key antigen for early pregnancy detection.

Abstract Objectives Hyperglycosylated human chorionic gonadotrophin (hCG) is an hCG variant with extra-large O-linked oligosaccharides, produced by phenotypically invasive cytotrophoblast cells in choriocarcinoma and pregnancy. It is the principal form of hCG produced in the first weeks of gestation. We investigated the importance of hyperglycosylated hCG in pregnancy testing and its detection by current hCG tests. Design and methods We measured the concentration of hyperglycosylated hCG and total hCG in 512 pregnancies throughout gestation. We assessed and compared the abilities of 14 commonly used commercial laboratory hCG tests and 18 home pregnancy tests to detect regular and hyperglycosylated hCG. Results Hyperglycosylated hCG is the principal source of hCG-related immunoreactivity in early pregnancy. In the week following missing menses, hyperglycosylated hCG measurements may be more sensitive than regular hCG measurements in detecting pregnancy. Of 14 commercial laboratory hCG tests, 3 appropriately detected hyperglycosylated hCG standard. Of 18 different home pregnancy products 11 poorly or very poorly detected this key antigen. Conclusions Hyperglycosylated hCG may be the key molecule in the detection of early pregnancy. However, the majority of tests poorly detected or failed to detect this key antigen. New pregnancy tests are needed that either solely detect hyperglycosylated hCG or equally detect regular hCG and hyperglycosylated hCG.
Inhibition of DMBA-induced mammary tumorigenesis by caloric restriction in rats fed high-fat diets.

Most previous studies on the inhibiting effect of caloric restriction during promotion of DMBA-induced mammary carcinogenesis have used low to moderate levels of dietary fat, i.e., about 4 to 14% by weight. The current study was designed to test whether a moderate degree of caloric restriction, 25%, would inhibit tumor growth in rats fed the equivalent of 20% dietary fat which approximates human consumption in affluent countries. Rats were fed diets ad libitum that contained 5, 15 or 20% corn oil. Groups of rats were pair-fed to the last 2 groups, but subjected to a 25% caloric restriction. These groups were fed 20 or 26.7% corn oil so that absolute fat intake in the paired groups was identical. Significant inhibition of tumor incidence, tumor weight, tumor burden, body fat deposition, and fasting serum insulin were observed in the 2 calorically restricted groups. We conclude that moderate caloric restriction is significantly more effective in inhibiting tumor growth than is the promoting effect of diets high in fat. Total body weight, body fat and serum insulin concentrations may be better correlates of risk of developing mammary tumors than is dietary fat.
Laparoscopic component separation reduces postoperative wound complications but does not alter recurrence rates in complex hernia repairs

Abstract Background The purpose of this study was to evaluate and compare the incidence of wound complications after laparoscopic component separation (LCS) vs open component separation (OCS) in patients with complex abdominal wall hernias. Methods A retrospective review was performed of all patients who underwent LCS or OCS for repair of a complex abdominal wall hernia at a single institution between 2009 and 2011. Charts were reviewed to identify postoperative wound complications. A computed tomographic scan or physical examination was used for the determination of hernia recurrence. Categoric variables were compared using the Fisher exact test. Univariate and multivariate analyses were performed using linear and Cox regression. Recurrence rates were compared using log-rank tests (Kaplan-Meier method). Results A total of 44 patients underwent LCS (n = 18) or OCS (n = 26). There was no statistically significant difference between categoric variables. Multivariate analysis using wound complications as the dependent variable showed a statistically significantly lower rate of wound complications in the LCS group. Conclusions LCS is associated with a lower rate of wound complications when compared with OCS but yields comparable recurrence rates.
Assessing Presidential Support in the House: Lessons from Reagan and Carter

President Reagan's record of congressional victories in a Democratic controlled House surprised most political observers. The stark contrast between Reagan's success and Carter's failures leads many to conclude that President Reagan is a master legislative leader. But was Reagan more successful than one would expect given political conditions in 1981? Was Carter less successful than one would expect given political conditions in 1977? This paper uses a multivariate regression model of relationships between presidential support in the House and several political structure variables for the period 1959 to 1974 to predict support for Reagan in 1981 and Carter in 1977. Analysis of the "forecast errors"--i.e., the difference between House members' actual level of support and the level of support predicted by the model--reveals whether the president is more or less successful than one would expect given the influence of political structures such as party, ideology, and presidential popularity with the public. I...
Job design in the context of the job market

This paper examines issues in job design from the perspective of developments in the labor market. Among the issues considered are the impact of technological change, shifts in how work is organized, the changing balance of power between employers and employees, the growing diversity in employment practices among similarly situated firms, and the persistence of a large low wage sector in the labor market. All of this suggests that this is a dynamic and interesting time to study the interaction of job design and broader trends in the labor market. Copyright © 2010 John Wiley & Sons, Ltd.
A Tunable Voltage Correlator

We present a CMOS circuit with a voltage output that is a function of the correlation between its two voltage inputs. The DC offset, height, and width of the circuit's transfer function are independently tunable. The circuit has been fabricated in a commercially available 0.5 μm process, and testing has yielded experimental results that match well with theoretical analysis.
Radiophosphate (32-PO4) incorporation into phosphatidic acid of lead-poisoned and normalred cells.

SummaryRadiophosphate incorporation into phosphatidic acid is decreased in the red cells of lead-poisoned humans and rabbits. The decrease in activity is not related to the length of red cell survival nor to the differences in osmotic fragility observed in the lead-poisoned cells. Incorporation of radiophosphate into phosphatidic acid of normal red cells is sulfhydryl dependent and occurs at the cell surface. Lipid composition of the red cell membrane of the lead-poisoned humans and rabbits is normal.
Analyses of pesticides and their metabolites in foods and drinks

The importance of matrix pretreatment, sample extraction and clean-up in multiresidue methods for pesticide analyses is discussed, with emphasis on alternative new techniques attempted worldwide such as accelerated solvent extraction, microwave-assisted extraction, solid-phase extraction, solid-phase micro-extraction, matrix solid-phase dispersion, supercritical fluid chromatography, ultrasonic extraction and gel permeation chromatography. Detection employing capillary gas chromatography and high-performance liquid chromatography in conjunction with mass spectrometry, capillary electrophoresis, immunoassay techniques and others is summarized.
Think Better: Positive Neuropsychology

The general public is way ahead of us on positive neuropsychology. Beginning at the first signs of pregnancy, parents spend millions on toys, music, and devices that claim to stimulate neural conne...
The Rhesus monkey immunoglobulin IGHD and IGHJ germline repertoire.

In order to facilitate molecular analysis of antibody responses in Rhesus monkeys (Macaca mulatta), we used PCR techniques to clone and sequence the germline IGHD gene repertoire and the IGHD7–IGHJ6 locus in its entirety. We identified 30 distinct Rhesus DH genes belonging to seven subgroups and their recombination signal sequences that together share an average of 91% identity with their human counterparts, six potentially functional IGHJ genes and their recombination signal sequences that together share 93% identity with their human counterparts, as well as a novel IGHJ gene, IGHJ5β, which is a duplicated variant of IGHJ5. The presence, on average, of one additional IGHD gene in Rhesus IGHD subgroups when compared with human and one additional IGHJ gene suggests Rhesus has undergone at least two independent duplications beyond those that mark the human IGHD/IGHJ locus. Amino acid sequence composition is highly conserved between Rhesus and human, with IGHD insertions and deletions limited to three-nucleotide multiples, which serve to preserve enrichment for tyrosine, glycine, and serine residues in IGHD reading frame 1. The high degree of conservation between human and Rhesus IGHD and IGHJ genes supports the hypothesis that the germline repertoire encodes evolutionarily preferred antibody sequence as a result of selection for function.
The Interface between Distributed Systems and the OSI Architecture

This paper examines the problem of putting a distributed operating system on top of all seven layers of the ISO Open Systems Interconnect (OSI) architecture. Functional choices in distributed processing and current research activity in distributed computing are reviewed. Specific problems with interfacing current experimental distributed operating systems to the top three OSI layers are presented.
The Association of Individual and Neighborhood Social Cohesion, Stressors, and Crime on Smoking Status Among African-American Women in Southeastern US Subsidized Housing Neighborhoods

The purpose of this study was to examine the associations between individual and neighborhood social contextual factors and smoking prevalence among African-American women in subsidized neighborhoods. We randomly sampled 663 adult women in 17 subsidized neighborhoods in two Southeastern US states. The smoking prevalence among participants was 37.6 %, with an estimated neighborhood household prevalence ranging from 30 to 68 %. Smokers were more likely to be older, have lower incomes, have lower BMI, and live with other smokers. Women with high social cohesion were less likely to smoke, although living in neighborhoods with higher social cohesion was not associated with smoking prevalence. Women with higher social cohesion were more likely to be older and had lived in the neighborhood longer. Women with high stress (related to violence and disorder) and who lived in neighborhoods with higher stress were more likely to smoke. Younger women were more likely to have higher stress than older women. There were no statistically significant associations with objective neighborhood crime data in any model. This is the first study to examine both individual and neighborhood social contextual correlates among African-American women in subsidized neighborhoods. This study extends findings about smoking behaviors and neighborhood social contexts in this high-risk, urban population. Future research is needed to explore age and residential stability differences and perceptions of social cohesion, neighborhood disorder, and perceived violence in subsidized housing. Further research is also warranted on African-American women, subsidized housing, smoking, social context, health disparities’ effective strategies to address these individual and contextual factors to better inform future ecological-based multilevel prevention, and cessation intervention strategies.
Karyotype of Geomys pinetis (Mammalia: Geomyidae), with a discussion of the chromosomal relationships within the genus.

4 of the 5 subspecies ofGeomys pinetis were karyotyped. All specimens examined had a diploid number of 42 and a fundamental number of 80. This karyotype was compared with the described karyotypes of other species ofGeomys and was considered to be derived from an ancestoral form having a karyotype of about 70 acrocentric elements.
TETRAZOLIUM CHLORIDE AS A TEST REAGENT FOR FREEZING INJURY OF SEED CORN

Rapid methods for estimating viability in seeds have been suggested by a number of workers. Most of these are dependent upon the increased permeability (6, 10) or decreased reducing power (5, 8) of dead cells or tissues. Staining methods involving the reduction of selenium salts (4) or of tetrazolium compounds (9, 11) to colored forms by the action of living cells seem to be the most promising quick tests of viability. These tests should be particularly applicable to estimations of freezing injury in seed corn because: (a) corn is easily tested (11), (b) immature corn shows a degree of dormancy (13) which makes routine laboratory tests of germinability difficult and slow, and (c) speed is always essential to determine whether frozen seed corn is sufficiently viable to justify expensive processing, or whether the crop should be diverted to other uses.
Factors influencing the need for target vessel revascularization after renal artery stenting.

PURPOSE: To provide additional insight into factors that may be associated with the need for target vessel revascularization (TVR) following de novo renal artery stenting during long-term follow-up. METHODS: A retrospective chart and database review was conducted to analyze the progress of all patients with de novo symptomatic renal artery stenosis who underwent stent-supported angioplasty under the auspices of the Single Operator, Single Center, Renal Stent Retrospective Study (SOCRATES). The records review identified 782 patients who were enrolled in the study between 1993 and 2004; after excluding 34 (4.5%) patients (lost to follow-up or inadequate data), 748 consecutive patients (412 women; mean age 70.7+/-9.7 years, range 37-92) were suitable for longitudinal analysis. The need for TVR was based on strict clinical criteria (> or =20% rise in serum creatinine, worsening hypertension, and/or recurrent flash pulmonary edema), and all patients underwent multidisciplinary evaluation before stenting and during follow-up. RESULTS: Follow-up spanned a mean 45.8+/-26.5 months. TVR was needed in 88 (10.03%) of 877 arteries and was best predicted by patient age < or =67 years (OR 2.91, p=0.0001), stent diameter < or =5.0 mm (OR 2.31, p=0.001), solitary functioning kidney (OR 2.01, p=0.048), history of lower extremity peripheral artery disease (OR 1.87, p=0.008), and antecedent history of stroke (OR 1.73, p=0.026). CONCLUSION: Renal artery stenting appears to be durable, with only 10% of stented arteries requiring TVR during clinically-based long-term follow-up. Arteries with a final stent diameter < or =5.0 mm were more than twice as likely to need TVR, as were patients with a solitary kidney. The authors acknowledge that clinical recurrence is not a surrogate for ultrasound surveillance after renal artery stenting, so prospective controlled trials will be needed to determine risk factors for restenosis.
Microarray analysis of murine limb bud ectoderm and mesoderm after exposure to cadmium or acetazolamide.

BACKGROUND: A variety of drugs, environmental chemicals, and physical agents induce a common limb malformation in the offspring of pregnant mice exposed on day 9 of gestation. This malformation, postaxial, right-sided forelimb ectrodactyly, is thought to arise via an alteration of hedgehog signaling. METHODS: We have studied two of these teratogens, acetazolamide and cadmium, using the technique of microarray analysis of limb bud ectoderm and mesoderm to search for changes in gene expression that could indicate a common pathway to postaxial limb reduction. RESULTS: Results indicated a generalized up-regulation of gene expression after exposure to acetazolamide but a generalized down-regulation due to cadmium exposure. An intriguing observation was a cadmium-induced reduction of Mt1 and Mt2 expression in the limb bud mesoderm indicating a lowering of embryonic zinc. CONCLUSIONS: We propose that these two teratogens and others (valproic acid and ethanol) lower sonic hedgehog signaling by perturbation of zinc function in the sonic hedgehog protein. Birth Defects Research (Part A), 2009. © 2009 Wiley-Liss, Inc.
Multi-elemental characterization of tunnel and road dusts in Houston, Texas using dynamic reaction cell-quadrupole-inductively coupled plasma–mass spectrometry: Evidence for the release of platinum group and anthropogenic metals from motor vehicles

Abstract Platinum group elements (PGEs) including Rh, Pd, and Pt are important tracers for vehicular emissions, though their measurement is often challenging and difficult to replicate in environmental campaigns. These challenges arise from sample preparation steps required for PGE quantitation, which often cause severe isobaric interferences and spectral overlaps from polyatomic species of other anthropogenically emitted metals. Consequently, most previous road dust studies have either only quantified PGEs or included a small number of anthropogenic elements. Therefore a novel analytical method was developed to simultaneously measure PGEs, lanthanoids, transition and main group elements to comprehensively characterize the elemental composition of urban road and tunnel dusts. Dust samples collected from the vicinity of high-traffic roadways and a busy underwater tunnel restricted to single-axle (predominantly gasoline-driven) vehicles in Houston, TX were analyzed for 45 metals with the newly developed method using dynamic reaction cell-quadrupole-inductively coupled plasma–mass spectrometry (DRC-q-ICP–MS). Average Rh, Pd and Pt concentrations were 152 ± 52, 770 ± 208 and 529 ± 130 ng g−1 respectively in tunnel dusts while they varied between 6 and 8 ng g−1, 10 and 88 ng g−1 and 35 and 131 ng g−1 in surface road dusts. Elemental ratios and enrichment factors demonstrated that PGEs in dusts originated from autocatalyst attrition/abrasion. Strong evidence is also presented for mobile source emissions of Cu, Zn, Ga, As, Mo, Cd, Sn, Sb, Ba, W and Pb. However, all other elements including rare earths most likely arose from weathering, erosion and resuspension of crustal material. These are the first such detailed measurements in Houston, the largest city in TX and fourth largest in the United States. We posit that such investigations will assist in better understanding PGE concentrations in urban environments while providing elemental data necessary to better understand anthropogenic influences on their biogeochemical cycling.
The activity coefficient and related thermodynamic quantities of HCl in 5 wt-% 1-butanol

Abstract Emf measurements of the cells of the type Pt; H 2 (g, 1 atm)/HCl ( m ) in 5 wt-% 1-butanol, AgCl/Ag at five different temperatures ranging from 5–45°C were used to derive (i) the standard potentials of the silver/silver-chloride electrode, (ii) the mean activity coefficients of HCl, (iii) the primary and secondary medium effects, (iv) the relative partial molal enthalpy, and (v) the thermodynamic constants for the process of transfer of HCl from water to 5 wt-% 1-butanol—water. The thermodynamic functions were calculated from the E N ° values and their temperature coefficients for 5 wt-% 1-butanol. The standard emf varied with temperature ( t , °C) according to the equation E m ° = 0·2029 − 7·135 × 10 −4 ( t − 25) − 15·21 × 10 −7 ( t − 25) 2 . The molality of the acid ranged from 0·005 to 0·09 mol/kg. The results are discussed in terms of the acid—base properties and the structure of the solvent.
The design, synthesis and physical chemical properties of novel human vasopressin V2-receptor antagonists optimized for parenteral delivery.

Abstract Ionizable groups were introduced onto the 10,11-dihydro-5 H -pyrrolo[2,1- c ][1,4]benzodiazepine scaffold of the vasopressin V 2 -antagonist WAY-VPA-985 in the search for molecules optimized for parenteral formulation. The synthesis and structure–activity relationships (SAR) are presented together with solubility data in a model parenteral system. The amine, WAY-140288 ( 4f ), was chosen for further development.
New moccasins: articulating research approaches through interviews with faculty and staff at Native and non-Native academic institutions.

Objective The goals of this study were to explore the perceptions of professionals concerning research, its different approaches, and appropriate future directions with Native American communities, particularly in relation to nutrition issues. Design Semistructured qualitative interviews. setting: Interviews were conducted at Native and non-Native academic institutions, at other relevant locations, and over the telephone. Participants Participants (N = 20) were from Native and non-Native academic institutions and had experience working with research in Native American communities. Phenomena of interest Relationships between Native and non-Native academic institutions, worldviews regarding research and American Indian communities, and beneficial research within American Indian communities. Analysis Interviews were audiotaped, transcribed verbatim, and returned to the participants for review. Analysis of interview material involved eliciting themes. Results Some participants acknowledged different cultural worldviews in relation to research. Many participants provided insight on how to define beneficial research. Most said building trust between Native and non-Native academic institutions is an important step in developing effective research relationships. Conclusions and implications These findings are a first step toward creating a more equitable process of research that acknowledges different cultural worldviews and values community involvement within Native American communities.
Pt3Sn Nanoparticles with Controlled Size: High-Temperature Synthesis and Room-Temperature Catalytic Activation for Electrochemical Methanol Oxidation

We report a new method of preparing carbon-supported Pt3Sn nanoparticle catalysts for methanol and CO oxidation. Alloyed Pt3Sn nanoparticles with a cubic phase were synthesized by coreduction of platinum acetylacetonate and tin acetylacetonate in a high-boiling solvent, trioctylamine. Particle sizes in the range of 3.0 to 6.5 nm were controlled by varying the amount of introduced capping agents (oleylamine and oleic acid). The as-prepared particles displayed a narrow size distribution and were catalytically inactive. The ligands were removed to activate the nanoparticles for catalysis by treatment with tetramethylammonium hydroxide (TMAOH) solution. The treated Pt3Sn particles can be stabilized in TMAOH solution and finally loaded on XC-72 carbon support by physical deposition. Cyclic voltammetry and CO-stripping showed that all the Pt3Sn particles exhibited high electrocatalytic activity for methanol and CO oxidation. The size-dependent CO-stripping study indicated COads oxidation started at low potentia...
Public health perspectives of channelized and unchannelized headwater streams in central Ohio: a case study

Headwater streams constitute the majority of watersheds in the United States and many in the midwest have been channelized for agricultural drainage. Public health implications of water chemistry and aquatic insects within channelized and unchannelized headwater streams have not been explored. We sampled water chemistry and aquatic insects in two channelized and two unchannelized headwater streams in central Ohio from December 2005 until November 2008. Maximum concentrations of ammonium, nitrate plus nitrite, and chlorothalonil were greater in channelized streams. Nitrate plus nitrite and atrazine also exceeded drinking water standards more often in channelized streams. Maximum concentrations of simazine and the percentage of times it exceeded the drinking water standards were greater in unchannelized streams. The predicted hazard potential of nutrient and pesticide mixtures was greater in channelized streams. Mosquito abundance did not differ between stream types. Chironomid abundance was greater in channelized streams. Biting dipterans did not exhibit consistent abundance trends and only differed between stream types in the summer and fall. Our results suggest that if whole stream uptake of nutrients and pesticides is minimal in channelized headwater streams then nutrient and pesticide inputs from these streams may impact downstream drinking water sources. Our results also suggest channelized and unchannelized headwater streams are not serving as a significant source of mosquitoes.
Decision feedback equalizer for nonlinear time-varying channels using type-2 fuzzy adaptive filters

Presents a decision feedback equalizer (DFE) that uses type-2 fuzzy adaptive filters (FAFs). These FAFs are realized using an unnormalized type-2 TSK fuzzy logic system. We apply our DFE to a nonlinear time-varying channel, and demonstrate that it can implement the Bayesian equalizer for such a channel, has a simple structure, and provides fast inference. A clustering method is used to adaptively design the parameters of the FAF. Our DFE vastly reduces computational complexity as compared to a transversal equalizer. Simulation results show that our type-2 FAF-based DFE performs much better than nearest neighbor classifiers or a DFE based on type-1 FAFs.
An assessment of Motorola CodeLink microarray performance for gene expression profiling applications.

DNA microarrays enable users to obtain information on differences in transcript abundance on a massively parallel scale. Recently, however, data analyses have revealed potential pitfalls related to image acquisition, variability and misclassifications in replicate measurements, cross-hybridization and sensitivity limitations. We have generated a series of analytical tools to address the manufacturing, detection and data analysis components of a microarray experiment. Together, we have used these tools to optimize performance in an expression profiling study. We demonstrate three significant advantages of the Motorola CodeLink™ platform: sensitivity of one copy per cell, coefficients of variation of 10% in the hybridization signals across slides and across target preparations, and specificity in distinguishing highly homologous sequences. Slides where oligonucleotide probes are spotted in 6-fold redundancy were used to demonstrate the effect of replication on data quality. Lastly, the differential expression ratios obtained with the CodeLink™ expression platform were validated against those obtained with quantitative reverse transcription–PCR assays for 54 genes.
Efficiency of cloud condensation nuclei formation from ultrafine particles

Atmospheric cloud condensation nuclei (CCN) concentrations are a key uncertainty in the assessment of the effect of anthropogenic aerosol on clouds and climate. The ability of new ultrafine particles to grow to become CCN varies throughout the atmosphere and must be understood in order to understand CCN formation. We have developed the Probability of Ultrafine particle Growth (PUG) model to answer questions regarding which growth and sink mechanisms control this growth, how the growth varies between different parts of the atmosphere and how uncertainties with respect to the magnitude and size distribution of ultrafine emissions translates into uncertainty in CCN generation. The inputs to the PUG model are the concentrations of condensable gases, the size distribution of ambient aerosol, particle deposition timescales and physical properties of the particles and condensable gases. It was found in most cases that condensation is the dominant growth mechanism and coagulation with larger particles is the dominant sink mechanism for ultrafine particles. In this work we found that the probability of a new ultrafine particle generating a CCN varies from <0.1% to ~90% in different parts of the atmosphere, though in the boundary layer a large fraction of ultrafine particles have a probability between 1% and 40%. Some regions, such as the tropical free troposphere, are areas with high probabilities; however, variability within regions makes it difficult to predict which regions of the atmosphere are most efficient for generating CCN from ultrafine particles. For a given mass of primary ultrafine aerosol, an uncertainty of a factor of two in the modal diameter can lead to an uncertainty in the number of CCN generated as high as a factor for eight. It was found that no single moment of the primary aerosol size distribution, such as total mass or number, is a robust predictor of the number of CCN ultimately generated. Therefore, a complete description of the emissions size distribution is generally required for global aerosol microphysics models.
Focused Ultrasound-Mediated Drug Delivery From Microbubbles Reduces Drug Dose Necessary for Therapeutic Effect on Neointima Formation—Brief Report

Objective— We hypothesized that (1) neointima formation in a rat carotid balloon injury model could be reduced in vivo following targeted ultrasound delivery of rapamycin microbubbles (RMBs), and (2) the addition of dual-mode ultrasound decreases the total amount of drug needed to reduce neointima formation. Methods and Results— Balloon injury was performed in rat carotids to induce neointima formation. High or low doses of RMBs were injected intravenously and ruptured at the site of injury with ultrasound. Compared with nontreated injured arteries, neointima formation was reduced by 0% and 35.9% with 108 RMBs and by 28.7% and 34.9% in arteries treated with 109 RMBs with and without ultrasound, respectively. Conclusion— Without ultrasound, 10-fold higher concentrations of RMBs were needed to reduce neointima formation by at least 28%, whereas 108 RMBs combined with ultrasound were sufficient to achieve the same therapeutic effect, demonstrating that this technology may have promise for localized potent drug therapy.
High-Frequency Ventilation A Review

High-frequency ventilation (HFV) is a form of artificial ventilation that uses higher rates and smaller tidal volumes than those used with conventional mechanical ventilation (intermittent positive pressure ventilation [1PPV]). HFV is divided into three categories based on the rate and type of equipment used: 1) high-frequency positive pressure ventilation administered through a system with low internal compliance having an expiratory valve to maintain positive airway pressure during expiration and rates of 60 to 120/minute; 2) high-frequency jet ventilation delivered through an open system or a system with an expiratory valve at rates of 120 to 400/minute; and 3) high-frequency oscillation using open systems and rates of 400 to 2400/minute. All forms of HFV provide adequate ventilation in normal animals at lower peak and mean airway pressures, resulting in less cardiovascular depression than that associated with 1PPV. HFV provides adequate ventilation with less cardiovascular depression and risk of barotrauma than 1PPV in the presence of pulmonary disease. The exact mechanism of gas exchange during HFV is not clearly understood, but enhanced diffusion as a result of turbulent gas flow appears to be a major factor.
The Drosophila Nephrocyte: Back on Stage

Drosophila nephrocytes have been an object of study for more than a century. They were named by Bruntz, based on observations of cells around the heart, the central nervous system, and in the sternal area in scorpions.[1][1] Kowalevsky suggested that they function as a storage kidney, because they
Modeling the sharp compositional interface in the Pu`u `Ō`ō magma reservoir, Kīlauea volcano, Hawai`i

[1] Lavas from the early episodes of the Pu`u `Ō`ō eruption (1983–1985) of Kīlauea Volcano on the island of Hawai`i display rapid compositional variation over short periods for some episodes, especially the well-sampled episode 30 with ∼2 wt% MgO variation in <4 hours. Little chemical variation is observed within the episode 30 lavas before or after this abrupt change, suggesting a sharp compositional interface within the Pu`u `Ō`ō dike-like shallow reservoir. Cooling-induced crystal fractionation in this reservoir is thought to be the main control on intraepisode compositional variation. Potential explanations for a sharp interface, such as changing reservoir width and wall rock thermal properties, are evaluated using a simple thermal model of a dike-like body surrounded by wall rock with spatially variable thermal conductivity. The model that best reproduces the compositional data involves a change in wall rock thermal conductivity from 2.7 to 9 W m−1 C−1, which is consistent with deep drill hole data in the east rift zone. The change in thermal conductivity may indicate that fluid flow in the east rift zone is restricted to shallow depths possibly by increasing numbers of dikes acting as aquicludes and/or decreasing pore space due to formation of secondary minerals. Results suggest that wall rock thermal gradients can strongly influence magma chemistry in shallow reservoirs.
Health Problems of Refugees

Background: The United States has recently seen an increase in the number of refugees and a change in the ethnicity of these refugees. It would be helpful for family physicians providing medical care to these patients to have available health data on the largest groups of new refugees. Methods: Using the key words “refugee” “Vietnam” “Laos” “former Yugoslavia” (Bosnia-Herzegovina) “former Soviet Union” “Iraq” “Afghanistan” “Somalia” “Sudan” “Ethiopia” “Haiti” and “Cuba” the MEDLINE files were searched from 1991 to the present. Cross-references from these articles were also reviewed, including pertinent information published from 1981-91. Studies and experimental trials were discussed if they had information on conditions of refugees after arrival or on diseases currently reported from the countries of origin. Results and Conclusions: With the exception of studies of Southeast Asian refugees, there are few clinical trials on the health problems of refugees after arrival in the United States. Tuberculosis, nutritional deficiencies, intestinal parasites, chronic hepatitis B infection, lack of immunization, and depression are major problems in many groups. There is great variation in the health and psychosocial issues, as well as cultural beliefs, among the refugees. In addition to a complete history and physical examination, tests for tuberculosis, hepatitis B surface antigen, and ova and parasites, as well as a hemoglobin measurement, are advised for most groups. Ongoing clinical trials are needed to explore more fully not only the medical and psychological problems of these patients but also their health beliefs.
Greater elevation in risk for nicotine dependence per pack of cigarettes smoked among those with an anxiety disorder.

Objective:Recent work shows that the time from the initial use of nicotine, cannabis, and alcohol to the onset of dependence on these substances is shorter (“telescoped”) in anxiety-disordered individuals. Previously, we hypothesized that telescoping may result from a shared neurobiology underlying both anxiety disorders and dependence. This hypothesis implies that telescoping occurs because individuals with an anxiety disorder transition to dependence with less overall drug exposure (“dependence susceptibility”). To investigate this further, we examined an estimate of the amount smoked (rather than the time transpired) from smoking initiation milestones to the onset of nicotine dependence in those with and without an anxiety disorder.Method:We used the subset of respondents in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) Wave 1 who reported having smoked at least 100 cigarettes (N = 18,013). All data were based on face-to-face interviews.Results:Individuals with any anxiet...
PRODUCCIÓN DE SUBJETIVIDAD A PARTIR DE LOS DISCURSOS GUBERNAMENTALES DEL ESTADO DE CHILE SOBRE LA DISCAPACIDAD

Las transformaciones de las ultimas decadas en el ambito productivo y social del Capital han reformado los procesos y practicas institucionales de produccion de subjetividad. La presente ponencia expone algunos de los resultados de una investigacion que procura describir y analizar de forma exploratoria los procesos en que la discursividad del Estado de Chile desplegada entre los anos 1992 y 2011 surge como territorio referencial para los sujetos, especificamente en el ambito de aquellos cuerpos denomina- dos discapacitados. El estudio fue realizado entendiendo que dichos cambios se dan a partir de rupturas y continuidades que despliegan campos de inteligibilidad flexibles que gobiernan la vida de los sujetos. La nocion de gubernamentalidad remite segun Foucault al gobierno de la poblacion a partir del ensamble de tecnologias de gobierno y racionalidades politicas en determinadas sociedades. En el marco de los estudios sobre la gubernamentalidad, en este articulo presentamos algunos lineamientos que hemos identificado para comprender las nuevas logicas de conduccion de conducta y su constitucion como politicas de intervencion que modifican en un mismo movimiento la subjetividad y materialidad de los cuerpos clasificados y senalados como diferentes.
A low-polynomial algorithm for assembling clusters of orthologous groups from intergenomic symmetric best matches

Motivation: Identifying orthologous genes in multiple genomes is a fundamental task in comparative genomics. Construction of intergenomic symmetrical best matches (SymBets) and joining them into clusters is a popular method of ortholog definition, embodied in several software programs. Despite their wide use, the computational complexity of these programs has not been thoroughly examined. Results: In this work, we show that in the standard approach of iteration through all triangles of SymBets, the memory scales with at least the number of these triangles, O(g3) (where g = number of genomes), and construction time scales with the iteration through each pair, i.e. O(g6). We propose the EdgeSearch algorithm that iterates over edges in the SymBet graph rather than triangles of SymBets, and as a result has a worst-case complexity of only O(g3log g). Several optimizations reduce the run-time even further in realistically sparse graphs. In two real-world datasets of genomes from bacteriophages (POGs) and Mollicutes (MOGs), an implementation of the EdgeSearch algorithm runs about an order of magnitude faster than the original algorithm and scales much better with increasing number of genomes, with only minor differences in the final results, and up to 60 times faster than the popular OrthoMCL program with a 90% overlap between the identified groups of orthologs. Availability and implementation: C++ source code freely available for download at ftp.ncbi.nih.gov/pub/wolf/COGs/COGsoft/ Contact: [email protected] Supplementary information:Supplementary materials are available at Bioinformatics online.
AMP-18 protects barrier function of colonic epithelial cells: role of tight junction proteins

Antrum mucosal protein (AMP)-18 and a synthetic peptide of amino acids 77-97 have mitogenic and motogenic properties for epithelial cells. The possibility that AMP-18 is also protective was evaluated in the colonic mucosa of mice and monolayer cultures of human colonic epithelial Caco-2/bbe (C2) cells. Administration of AMP peptide to mice with dextran sulfate sodium (DSS)-induced colonic injury delayed the onset of bloody diarrhea and reduced weight loss. Treatment of C2 cells with AMP peptide protected monolayers against decreases in transepithelial electrical resistance induced by the oxidant monochloramine, indomethacin, or DSS. A molecular mechanism for these barrier-protective effects was sought by asking whether AMP peptide acted on specific tight junction (TJ) proteins. Immunoblots of detergent-insoluble fractions of C2 cells treated with AMP peptide exhibited increased accumulation of specific TJ proteins. Occludin immunoreactivity was also increased in detergent-insoluble fractions obtained from colonic mucosal cells of mice injected with AMP peptide. Observations using laser scanning confocal (CF) microscopy supported the capacity of AMP peptide to enhance accumulation of occludin and zonula occludens-1 in TJ domains of C2 cell monolayers and together with immunoblot analysis showed that the peptide protected against loss of these TJ proteins following oxidant injury. AMP peptide also protected against a fall in TER during disruption of actin filaments by cytochalasin D and stabilized perijunctional actin during oxidant injury when assessed by CF. These findings suggest that AMP-18 could protect the intestinal mucosal barrier by acting on specific TJ proteins and stabilizing perijunctional actin.
Why does my patient have lymphadenopathy or splenomegaly

Lymph node or spleen enlargement may be innocent or the first sign of a serious disorder. Lymphadenopathy and splenomegaly can be found in symptomatic or asymptomatic patients. Lymph node enlargement in a single region or multiple sites can be seen in various diseases, including infections, noninfectious inflammatory conditions, or malignancies; a similar differential diagnosis applies to splenomegaly, but splenomegaly can also be caused by vascular abnormalities and hemolysis. Frequently, lymphadenopathy is detected incidentally during screening examinations or imaging procedures. This review focuses on causes of lymphadenopathy and splenomegaly and an appropriate diagnostic approach to patients with lymphadenopathy or splenomegaly.