cssi/SciSciGPT-SciSciNet huggingface dataset:
The Temporal Patterning MicroRNA let-7 Regulates Several Transcription Factors at the Larval to Adult Transition in C. elegans

Summary The let-7 microRNA is phylogenetically conserved and temporally expressed in many animals. C. elegans let-7 controls terminal differentiation in a stem cell–like lineage in the hypodermis, while human let-7 has been implicated in lung cancer. To elucidate let-7 's role in temporal control of nematode development, we used sequence analysis and reverse genetics to identify candidate let-7 target genes. We show that the nuclear hormone receptor daf-12 is a let-7 target in seam cells, while the forkhead transcription factor pha-4 is a target in the intestine. Additional likely targets are the zinc finger protein die-1 and the putative chromatin remodeling factor lss-4 . Together with the previous identification of the hunchback ortholog hbl-1 as a let-7 target in the ventral nerve cord, our findings show that let-7 acts in at least three tissues to regulate different transcription factors, raising the possibility of let-7 as a master temporal regulator.
Beef shank fat solubility in supercritical carbon dioxide-propane mixtures and in liquid propane

For propane, conditions were 298K and 308K at the liquid vapor pressure. For supercritical mixtures, conditions were 308K at pressures from 8.9 to 15.7 MPa. The solubility of fat in CO 2 -propane increased with increasing pressure, up to 0.66wt% at 15.7 MPa. The average solubility of the fat in propane at 298K was 16.7wt% and at 308K it was 21.4wt%. The extracted fat was solid with a melting range of 295-314K. There was no apparent degradation of collagen during extractions. Beef shank fat extraction with propane is feasible and advantageous over use of supercritical CO 2 -propane.
Is a heftier administrative law required to prevent state hollowing?: the issue of transborder water pollution

Concerns regarding the management of water and air pollution in border regions – such as the California‐Mexico Border, is an old issue, which has bubbled up to its current crisis situation. Health and safety disasters, stemming from water pollution on both sides of the border mount as do related costs to local financially‐strapped communities in California. One such impacted community is Imperial County, California, which must deal with the consequences stemming from the “dirtiest river in the United States”. This refers to The New River which enters the US through Mexico. While NAFTA has promoted the growth of globalized companies and industries in the region, progress has added to pollution. Regulation is far from evenly matched in the two countries. To manage negative spillover effects from globalism across borders, the time has come for development of new administrative law, with strict penalties for violators. This article uses the impact of pollution from The New River to discuss the hollowing of our nation‐state’s democratically‐derived mandate against pollution. It also raises the question of whether we have the stomach to push for new administrative law and risk multinational flight to other more accommodating regions, or live with the status quo and its serious human and environmental consequences.
Endogenous lectins in chickens and slime molds: Transfer from intracellular to extracellular sites

Endogenous lectins in both cellular slime molds and chicken tissues have been localized primarily intracellularly, in contrast with the predominantly extracellular localization of the glycoproteins, glycolipids, and glycosaminoglycans with which they might interact. Here we present evidence that lectins in both of these organisms may be externalized and become associated with the cell surface and/or extracellular materials. In chicken intestine, chicken-lactose-lectin-II is shown to be localized in the secretory granules of the goblet cells, along with mucin, and to be secreted onto the intestinal surface. In embryonic muscle, chicken-lactose-lectin-I is shown to be externalized with differentiation, ultimately becoming localized on the surface of myotubes and in the extracellular spaces. In a cellular slime mold, Dictyostelium purpureum, externalization of lectin is elicited by either polyvalent glycoproteins that bind the small amount of endogenous cell surface lectin, or by slime mold or plant lectins that bind unoccupied complementary cell surface oligosaccharides. These results suggest that externalization of endogenous lectin may be a response to specific external signals. We conclude that lectins are frequently held in intracellular reserves awaiting release for specific external functions.
Trends in gastroenteritis-associated mortality in the United States, 1985-2005: variations by ICD-9 and ICD-10 codes.

Trends in gastroenteritis-associated mortality are changing over time with development of antibiotic resistant strains of certain pathogens, improved diagnostic methods, and changing healthcare. In 1999, ICD-10 coding was introduced for mortality records which can also affect trends. We assess trends in gastroenteritis-associated mortality and changes associated with coding. Trends in gastroenteritis-associated mortality rates in the United States were examined using the National Center for Health Statistics Multiple Cause-of-Death Mortality databases for 1985–2005. All deaths with the underlying cause or any contributing cause included gastroenteritis were included. Cases were selected based on ICD9 (pre-1999) and ICD10 (1999–2005) codes and all analyses were stratified by ICD usage. Annual trends in age adjusted mortality rates were assessed using linear regression spline analysis. Relative risks and 95% confidence intervals (CIs) were calculated using Poisson regression adjusted for age group, sex, race, and region. There were a total of 190,674 deaths related to gastroenteritis in the U.S. from 1985–2005 with an average of 9,080 per year. During this time the percent of deaths related to gastroenteritis more than tripled, increasing from 0.25% to 0.80% of all deaths. Though the time periods varied in length, we demonstrate a significant increase in slope from a 0.0054% annual increase during the period 1985–1998, when ICD-9 coding was used, to a 0.0550% annual increase during 1999–2005, when ICD-10 coding was used. For both time periods, the oldest age group (75+ years) demonstrated the highest risk of death due to gastroenteritis. Additionally, males demonstrated higher risk than females and blacks were at higher risk than whites for death due to gastroenteritis. This analysis demonstrates the public health burden of gastroenteritis-associated mortality in the United States and changes in trends due to change from ICD-9 to ICD-10 coding. The overall rate of gastroenteritis-associated mortality has more than tripled over the 21-year period from 1985 to 2005 and the primary burden of deaths due to gastroenteritis is in the elderly population.
Effect of Curing Agents on the Growth and Survival of Food‐Poisoning Strains of Clostridium perfringens

SUMMARY The effects of different combinations of curing salts (NaCl, NaNO3, NaNO2) and temperature on the growth, survival, and heat resistance of several strains of Clostridium perfringens were investigated. These strains were shown to survive and grow in concentrations of curing salts considerably higher than those used in normal curing operations. When used in conjunction with heat, the concentrations of curing salts required to affect cell survival were still well above those usually employed. Hams were pumped with curing brines inoculated with low concentrations of spores of a food-poisoning strain of C. perfringens, then cured and smoked according to routine procedures, C. perfringens could still be isolated from the hams after cooling. A simple procedure for preparing reproducible inocula of aged spores is described. These aged spores showed much greater resistance to heat after storage in meat-brine mixtures than did spores from young sporulating cultures.
Teaching Reprint File Management: Basic Principles and Software Programs

During the past three‐and‐a‐half years, over 150 faculty members, researchers, and support staff at the University of Southern California (USC) Health Sciences Campus have attended a three‐hour workshop, developed and written by myself, on reprint file management. The workshop is offered bimonthly as part of a teaching program in bibliographic management and computer literacy that has been developed by the library. The program as a whole includes:
INCREASED PRODUCTION OF LOW MOLECULAR WEIGHT RECOMBINANT PROTEINS IN ESCHERICHIA COLI

A general method for obtaining high-level production of low molecular weight proteins in Escherichia coli is described. This method is based on the use of a novel Met-Xaa-protein construction which is formed by insertion of a single amino acid residue (preferably Arginine or Lysine) between the N-terminal methionine and the protein of interest. The utility of this method is illustrated by examples for achieving high-level production of human insulin-like growth factor-1, human proinsulin, and their analogs. Furthermore, highly produced insulin-like growth factor-1 derivatives and human proinsulin analogs are converted to their natural sequences by removal of dipeptides with cathepsin C.
Dehalogenation of 2,6-dibromobiphenyl and 2,3,4,5,6-pentachlorobiphenyl in contaminated estuarine sediment.

Estuarine sediments from a USEPA Superfund site in coastal Georgia were extensively contaminated with Aroclor 1268, a mixture of highly chlorinated polychlorinated biphenyls used by a former chlor-alkali plant. Batch slurries of contaminated sediment were incubated for 1 yr with amendments of 2,6-dibromobiphenyl (26-BB) and 2,3,4,5,6-pentachlorobiphenyl (23456-CB) under anaerobic, sulfate-reducing conditions and different pH (5.5–7.5). Organic extracts of slurry sub-samples in a time series were analyzed by congener-specific GC–MS. Dechlorination of 23456-CB was pH dependent and occurred via two routes with the sequential loss of (1) meta and para chlorines and (2) para, ortho, and meta chlorines. Quantitative dehalogenation of 26-BB was observed at all pH. Supplementation of nonachlorobiphenyls (as primers) did not induce dechlorination of native Aroclor 1268 nor of the primers themselves. While contaminated estuarine sediments possess microbial consortia with diverse dehalogenating activities, lack of dechlorination of Aroclor 1268 and spiked nonachlorobiphenyl congeners suggests a bioavailability limitation or enzyme–substrate incompatibilies.
Modeling and optimization of the dilute-sulfuric-acid pretreatment of corn stover, poplar and switchgrass

Lignocellulosic biomass may be used as a potential renewable feedstock for biochemical production of ethanol as an alternative transportation fuel. However, cellulose, which is the major source of fermentable sugars in these materials, is protected by a network of lignin and hemicellulose. The dilute-sulfuric-acid pretreatment removes this protecting shield and makes the cellulose more susceptible to enzymatic digestion. In this study, three lignocellulosic feedstocks (i.e. corn stover, poplar and switchgrass) were pretreated with dilute sulfuric acid (0.6, 0.9 and 1.2% w/w) at relatively high temperatures (140, 160 and 180°C) in a Parr batch reactor. The hydrolysis of hemicellulose to its monomeric constituents and possible degradation of these monomers were modeled by a series of first-order reactions. The kinetic parameters of two mathematical models for predicting the percentage of xylan remaining in the substrate after pretreatment and the net xylose yield in the liquid stream were determined using the actual acid concentration in the reactor after accounting for the neutralization effect of the substrates.
Profile of amino acid synthesis in rat hippocampus during push-pull perfusion of ethanol or morphine.

Abstract In the unanesthetized rat, the effect of ethanol or morphine on the new synthesis of six amino acids, γ-aminobutyrate, glutamate, alanine, aspartate, glycine and glutamine, was determined at circumscribed sites in the hippocampus. In the fasted animal, 5.0 μCi of [U-14C]glucose was microinjected in a volume of 1.01μl into a discrete region of the hippocampus through a permanently implanted guide tube. After 10–15 min, the tip of a concentric push-pull cannula assembly was lowered through the guide tube to the labelled site, and an isotonic artificial cerebrospinal fluid was continuously perfused at a rate of 25 μl/min. Samples of perfusate were collected every 5.0 min in a total volume of 125 μl. During the fourth perfusion, either ethanol (94 or 471 mM) or morphine (0.1 or 1.0 μg/μl) was added to the push-pull perfusate. Amino acids and glucose contained in each sample of perfusate were separated by means of a two-dimensional, thin-layer Chromatographie procedure. The results show that the 94 mM dose of ethanol acted only to significantly suppress the new synthesis of alanine. Conversely, the higher 471 mM dose of ethanol significantly increased the new synthesis of both glycine and glutamine from the glucose precursor. The effect of the 0.1 μg/μl morphine dose on amino acid synthesis paralleled that of the lower dose of ethanol since it evoked a similar decrease in the synthesis of alanine; however, the higher dose of 1.0 μg/μl morphine produced no effect. None of the other amino acids in the hippocampus were affected by either of the CNS depressants. Thus, whereas ethanol seems to exert significant stimulating activity on hippocampal synthesis of glycine and glutamine, morphine and ethanol possess the same inhibitory effect on alanine synthesis in this subcortical structure.
Electron photodetachment from a Dirac bubble potential. A model for the fullerene negative ion CC60

Abstract A model for the fullerene anion C 60 − is proposed in which the outer electron moves in an attractive deltafunction potential in the shape of a spherical bubble. Exact solutions for this “Dirac bubble potential” were previously worked out. On the basis of this model, the photodetachment cross-section and its angular distribution are computed as functions of photoelectron energy, for the electron in both S-like and P-like bound states. Secondary maxima and minima in the cross section appear at higher energy values, somewhat analogous to the scattering of radiation from a conducting sphere.
Parallel Computing in Civil Engineering

This issue marks the beginning of a new initiative in parallel computing. I would like to start with the statement by Grace Hopper 1910–1992 , pioneer computer scientist and U.S. Navy admiral, “In pioneer days they used oxen for heavy pulling, and when one ox couldn’t budge a log, they didn’t try to grow a larger ox but used more oxen. We shouldn’t be trying for bigger computers, but for more systems of computers.” The essence of this message is that it is very difficult to build a single processor computer that can handle the processing needs of any application. In other words, no matter how powerful a single processor computer is, there are always applications that require the power of parallel processing. The problems that we face as civil engineers are rapidly changing with increasing emphasis on homeland security, civil infrastructure protection, sustainability, and smart designs. These changing focuses put a premium on large-scale computation and real-time processing for many applications. Enabling parallel computation for these applications is not trivial due to inherent complexities of emerging parallel computing environments, lack of easily usable software libraries for these environments, and the dynamic nature of data and computation needs for some real-time processing applications. Consumer needs and economic reality have changed the face of parallel computing dramatically over the last two decades with the infusion of a new generation of supercomputers with hierarchical memory subsystems, nonuniform processor configurations, and heterogeneous geographically distributed grid computing environments. Obtaining good performance on these environments for real-world applications is extremely challenging even with available middleware tools such as MPI, Globus, Matlab distributed computing toolbox, and parallel numerical software such as PETSc, SCALAPACK, DAKOTA, ParMETIS, and Aztec. Therefore, prospective users such as civil engineers are forced to develop their own algorithms and/or implementations for their application needs. Despite the fact that parallel computing has been an active research area for the last two decades and that the demand for parallel computing is increasing in civil engineering, the leading computing journal in civil engineering, JCCE, has seen very few papers in this area averaging about one article per year . This editorial’s purpose is to change this trend by issuing a call to the civil engineering community to support an initiative in parallel computing. I will next address the type of parallel computing articles we would like to publish in JCCE, i.e., what do we want in a parallel computing article for JCCE? Prospective authors may consider the following questions:
Isoaspartate Accumulation in Mouse Brain Is Associated with Altered Patterns of Protein Phosphorylation and Acetylation, Some of Which Are Highly Sex-Dependent

Isoaspartate (isoAsp) formation is a major source of protein damage that is kept in check by the repair function of protein L-isoaspartyl methyltransferase (PIMT). Mice deficient in PIMT accumulate isoAsp-containing proteins, resulting in cognitive deficits, abnormal neuronal physiology and cytoarchitecture, and fatal epileptic seizures 30–60 days after birth. Synapsins I and II, dynamin-1, collapsin response mediator protein 2 (CRMP2), and α/β-tubulin are major targets of PIMT in brain. To investigate links between isoAsp accumulation and the neurological phenotype of the KO mice, we used Western blotting to compare patterns of in vivo phosphorylation or acetylation of the major PIMT targets listed above. Phosphorylations of synapsins I and II at Ser-9 were increased in female KO vs. WT mice, and acetylation of tubulin at Lys-40 was decreased in male KO vs. WT mice. Average levels of dynamin-1 phosphorylation at Ser-778 and Ser-795 were higher in male KO vs. WT mice, but the statistical significance (P>0.1) was low. No changes in phosphorylation were found in synapsins I and II at Ser-603, in CRMP2 at Ser-522 or Thr-514, in DARPP-32 at Thr-34, or in PDK1 at Ser-241. General levels of phosphorylation assessed with Pro-Q Diamond stain, or an anti-phosphotyrosine antibody, appeared similar in the WT and KO mice. We conclude that isoAsp accumulation is associated with altered functional status of several neuronal proteins that are highly susceptible to this type of damage. We also uncovered unexpected differences in how male and female mice respond to isoAsp accumulation in the brain.
Psychostimulants Affect Dopamine Transporter Lateral Mobility and Membrane Microdomain Distribution

Neurotransmitter reuptake by transporters is a major mechanism for terminating synaptic transmission. The human dopamine transporter (hDAT) is one of the main targets for psychostimulants, and is critical to DA homeostasis. Lipid rafts are specialized membrane microdomains that serve as organizing centers to regulate different cellular processes such as neurotransmission and trafficking. To begin to understand how psychostimulants, methamphetamine (METH) and amphetamine (AMPH), affect hDAT microdomain association, we utilized fluorescence recovery after photobleaching (FRAP) and density-gradient centrifugation. Our FRAP studies revealed significant changes in the rate (D) and extent (Mf) of the fluorescence recovery into the bleached region of the plasma membrane in cells expressing YFP-hDAT in the presence of METH but not AMPH. Substitution of five N-terminal Ser with Ala, (cannot be phosphorylated) or Asp (pseudo-phosphorylated), and removal of the 22 N-terminal amino acids restored the diffusion rate of the transporter to control levels. Using density-gradient centrifugation, we found that YFP-hDAT is distributed into both, classically defined, membrane raft and non-raft fractions. Incubating with METH and AMPH shifted YFP-hDAT from non-raft to raft fractions. We have previously shown that METH uniquely modulates the biophysical properties of DAT. Our present findings suggest that METH and AMPH cause hDAT to partition into lipid raft membrane microdomains, and the decrease in the hDAT diffusion rate evoked by METH- vs. AMPH-occupied DAT could suggest that the N-terminal domain of the transporter is associated with a distinct group of proteins when exposed to these psychostimulants, and may thus describe an underlying mechanism behind the addictive biological differences between these psychostimulants.
Acute myeloid leukemia presenting as bilateral proptosis from diffuse extraocular muscle infiltration

Abstract Purpose To report a case of acute myeloid leukemia with bilateral proptosis as the sole presenting sign. Design Observational case report. Methods A patient with bilateral proptosis was seen in consultation by pediatric ophthalmology. Results Complete blood count, computerized tomography, and bone marrow biopsy confirmed the diagnosis of acute myeloid leukemia, with the proptosis due to diffuse infiltration of all extraocular muscles. Conclusion In a child with the sudden onset of proptosis without any other systemic findings, the diagnosis of acute leukemia must be considered.
Cell-Mediated Immunity and Antibody Responses Elicited by Attenuated Salmonella enterica Serovar Typhi Strains Used as Live Oral Vaccines in Humans

The development of improved typhoid vaccines is a high global public health priority. However, their development has been hampered by a lack of information regarding the specific determinants of protective immunity to Salmonella enterica serovar Typhi (S. Typhi) infection in humans. Although antibodies to S. Typhi O, H, and Vi appear to be involved in protection against S. Typhi infection, it is unknown whether such antibodies mediate protection, act in conjunction with other adaptive responses, or serve as a surrogate for the presence of other, more dominant protective immune responses (e.g., cell-mediated immunity [CMI]). CMI responses elicited by immunization of subjects with attenuated S. Typhi oral vaccines include lymphoproliferation; production of type 1 cytokines (e.g., interferon- gamma and tumor necrosis factor- alpha ); and classical major histocompatibility complex (MHC) class Ia-restricted and novel, nonclassical MHC class Ib (human leukocyte antigen [HLA]-E)-restricted CD8(+) cytotoxic T cell responses. In sum, human immunity to S. Typhi elicited by immunization is unexpectedly broad and complex. However, the immunologic correlates of protection remain largely undefined.
Varieties of mutualistic interaction in population models

A Lotka-Volterra model of mutalism indicates eight possible cases, of which two lead to survival of both populations, two indicate inevitable extinction, and four are indeterminate, the result depending on the initial population sizes. Conventional neighborhood stability analysis is a poor indicator of the biological result expected. Modification of the Lotka-Volterra model to give non-linear isoclines is necessary to obtain a minimum of biological realism; this modified model is illustrated with an analysis of a legume-Rhizobium mutualism.
Analysis of the DRβ chains from two DRw6 cell lines (WT46 and WT52): recombination in vivo may have generated new haplotypes

The HLA-DRw6 haplotype of the class II major histocompatibility complex (MHC) antigens exhibits unusual complexity and cannot be uniquely typed serologically. The DRβ chains expressed by consanguineous homozygous DRw6 typing cells WT46 and WT52 were biochemically analyzed using three monoclonal antibodies (mAb) that recognize denatured DRβ chains. The results of isoelectric focusing and N-terminal sequencing demonstrate that each DRw6 B-cell line expresses two DRβ chains. Evidence of an exchange of mAb epitopes involving the two DRβ chains of one of these cell lines was obtained and may be explained by a recombinational mechanism involving reciprocal exchange of genetic segments of the DRβ chains, one of which may encode the putative DRw6 chain and the other the chain carrying the MT2 allotypic determinant. Since a recombinational hot spot has been shown to occur uniquely in the mouse MHC within the Eβ gene, the occurrence of a recombination within the human homolog, DR(MT2)β, could reflect some specific feature of this MHC region. Comparison of the DRβ chains of the WT46 and WT52 cell lines with those of a third DRw6 cell line, LB, suggests that two alleles of MT2 occur.
Unified software approach to power quality assessment and evaluation

Many utilities have initiated aggressive programs to address power quality (PQ) issues in their systems. Power quality issues span the full spectrum of electric generation, transmission and distribution, and end-use. The major thrust in the utility programs on PQ is on system/customer interface. The utility engineer is responsible to customer problems and since there are too many factors in the equation, a unified approach based on software is not only essential but the most effective solution. The utility engineer should have the following tools to respond adequately to the various power quality concerns: a large database that is accessed quickly; expertise available in an expert system; and customized analysis software that will provide quantitative answers to device-oriented problems. Intelligent systems design provides a rational path to a unified approach to PQ problems.
APL thinking finding array-oriented solutions

APL is used for processing arrays. This is very different from traditional programming languages, which process single numbers and characters. This difference requires different programming methods. Such methods are array oriented. Several approaches to creating array oriented APL programs are explained here.
End User Adoption of Enterprise Systems in Eastern and Western Cultures

Enterprise systems are gaining interest from both international practitioners and researchers, and this paper investigates enterprise systems management and implementation issues comparing Eastern and Western end users. This issue is important because currently enterprise systems involve end-users with different cultural backgrounds in the East and West. Thus, this paper applies enterprise systems adoption issues to cross-cultural end user perspectives in Japan (East) and the U.S. (West), based on the innovation diffusion theory, the self-determinant theory, and Hofstede's cultural dimensions. Academic and practical implications are discussed in the paper based on empirical findings found deeper in this paper.
Serologic Cross-Reactivity of Human IgM and IgG Antibodies to Five Species of Ebola Virus

Five species of Ebola virus (EBOV) have been identified, with nucleotide differences of 30-45% between species. Four of these species have been shown to cause Ebola hemorrhagic fever (EHF) in humans and a fifth species (Reston ebolavirus) is capable of causing a similar disease in non-human primates. While examining potential serologic cross-reactivity between EBOV species is important for diagnostic assays as well as putative vaccines, the nature of cross-reactive antibodies following EBOV infection has not been thoroughly characterized. In order to examine cross-reactivity of human serologic responses to EBOV, we developed antigen preparations for all five EBOV species, and compared serologic responses by IgM capture and IgG enzyme-linked immunosorbent assay (ELISA) in groups of convalescent diagnostic sera from outbreaks in Kikwit, Democratic Republic of Congo (n=24), Gulu, Uganda (n=20), Bundibugyo, Uganda (n=33), and the Philippines (n=18), which represent outbreaks due to four different EBOV species. For groups of samples from Kikwit, Gulu, and Bundibugyo, some limited IgM cross-reactivity was noted between heterologous sera-antigen pairs, however, IgM responses were largely stronger against autologous antigen. In some instances IgG responses were higher to autologous antigen than heterologous antigen, however, in contrast to IgM responses, we observed strong cross-reactive IgG antibody responses to heterologous antigens among all sets of samples. Finally, we examined autologous IgM and IgG antibody levels, relative to time following EHF onset, and observed early peaking and declining IgM antibody levels (by 80 days) and early development and persistence of IgG antibodies among all samples, implying a consistent pattern of antibody kinetics, regardless of EBOV species. Our findings demonstrate limited cross-reactivity of IgM antibodies to EBOV, however, the stronger tendency for cross-reactive IgG antibody responses can largely circumvent limitations in the utility of heterologous antigen for diagnostic assays and may assist in the development of antibody-mediated vaccines to EBOV.
Infrared absorption intensities for N2O3

Abstract A Fourier transform spectrometer has been used to measure the absorption intensity of the v 1 and v 3 bands of N 2 O 3 near 1830 and 1300 cm -1 , respectively. The measured integrated intensities were S ( v 1 ) = (613±103) × 10 -19 cm -1 /cm -2 - molecule and S ( v 3 ) = (476±97) × 10 -19 cm -1 / cm -2 - molecule . Digital spectral subtraction techniques were used to eliminate interference from NO, NO 2 , and N 2 O 4 present in equilibrium with the N 2 O 3 .
Methanotrophic Activity, Abundance, and Diversity in Forested Swamp Pools: Spatiotemporal Dynamics and Influences on Methane Fluxes

Methane oxidation (methanotrophy) in the water column and sediments of forested swamp pools likely control seasonal and annual emission of CH4 from these systems, but the methanotrophic microbial communities, their activities, locations, and overall impact, is poorly understood. Several techniques including 14CH4 oxidation assays, culture-based most probable number (MPN) estimates of methane-oxidizing bacteria (MOB) and protozoan abundance, MOB strain isolation and characterization, and PCR techniques were used to investigate methanotrophy at a forested swamp near Ithaca, New York. The greatest methanotrophic activity and largest numbers of MOB occurred predominantly at the low oxygen sediment/water interface in the water column. Seasonally, methanotrophic activity was very dynamic, ranging from 0.1 to 61.9 μ moles CH4 d−1 g−1 dry sediment, and correlated most strongly with dissolved inorganic carbon (r = 0.896). Incorporation of methanotrophic variables (abundance and activity) into existing CH4 flux reg...
Analysis of immune response in young and aged mice vaccinated with corn-derived antigen against Escherichia coli heat-labile enterotoxin.

Enterotoxigenic strains of Escherichia coli produce a heat-labile holotoxin (LT), which causes diarrhea. We engineered corn seeds to produce LT-B, the nontoxic subunit of LT, to serve as a plant-derived vaccine to traveler's diarrhea and as an adjuvant for co-administered proteins. We previously demonstrated that a strong mucosal and systemic antibody response is elicited in young mice with oral administration of corn-derived LT-B. The present study examined systemic and mucosal antibody responses to LT-B in young and aged mice, and recall responses to oral administration and injection of LT-B in aged mice. Specific IgA and IgG antibodies were detectable during an 11-mo period, although the concentration of antigen-specific antibodies declined gradually. Booster by feeding or injection dramatically increased the concentration of specific IgA from that seen in young mice. Specific IgG levels were boosted to concentrations similar to those in young mice. This effect may be age-dependent and related to prior immunization exposure. Analysis of the antibody response of naive aged mice against corn-derived LT-B demonstrated an age-related suppression in specific IgG production, but not specific IgA. These results may provide important information for edible vaccine strategies for young and aged individuals.
Fabrication of large-area and low mass critical-angle x-ray transmission gratings

Soft x-ray spectroscopy of celestial sources with high resolving power R = E/ΔE and large collecting area addresses important science listed in the Astro2010 Decadal Survey New Worlds New Horizons, such as the growth of the large scale structure of the universe and its interaction with active galactic nuclei, the kinematics of galactic outflows, as well as coronal emission from stars and other topics. Numerous studies have shown that a transmission grating spectrometer based on lightweight critical-angle transmission (CAT) gratings can deliver R = 3000-5000 and large collecting area with high efficiency and minimal resource requirements, providing spectroscopic figures of merit at least an order of magnitude better than grating spectrometers on Chandra and XMM-Newton, as well as future calorimeter-based missions. The recently developed CAT gratings combine the advantages of transmission gratings (low mass, relaxed figure and alignment tolerances) and blazed reflection gratings (high broad band diffraction efficiency, utilization of higher diffraction orders). Their working principle based on blazing through reflection off the smooth, ultra-high aspect ratio grating bar sidewalls has previously been demonstrated on small samples with x rays. For larger gratings (area greater than 1 inch square) we developed a fabrication process for grating membranes with a hierarchy of integrated low-obscuration supports. The fabrication involves a combination of advanced lithography and highly anisotropic dry and wet etching techniques. We report on the latest fabrication results of free-standing, large-area CAT gratings with polished sidewalls and preliminary x-ray tests.
Fault-containing self-stabilization using priority scheduling

Schedulers play a vital role in the design of distributed algorithms. This paper introduces priority scheduling that can be used to design as well as reason about correctness proofs at a higher level of abstraction. The application of priority scheduling in solving problems related to stabilization and fault containment in spanning tree generation is presented. This paper also presents an implementation of the priority scheduling scheme.
1628 CELLULAR GROWTH IN THE MATURING RABBIT KIDNEY CORTICAL COLLECTING TUBULE (CCT)

Postnatal development of the proximal nephron is characterized by non-linear growth as a function of time (AJP 245:F391, 1983). We were interested in describing maturation of the CCT, a distal segment whose embryological origin differs from that of the proximal tubule. Mid-CCTs from newborn (NB), 1 month old, and adult rabbits (n=4-7 animals per group) were isolated. Tubules (5-15 per animal) were measured for length and diameter, cell number (acridine orange), dry weight (quartz fiber balance) and K+ content (helium glow photometry). The number of cells/mm tubular length was similar in the NB and adult (534 ± 34 and 551 ± 22). Cell growth was characterized by 50-60% increases (p < 0.05) in volume (1105 ± 85 to 1633 ± 82 μm3/cell), dry weight (169 ± 15 to 260 ± 23 pg/cell), and K+ content (0.106±0.011 to 0.164±0.011 pmol/cell), with changes apparent only after 1 month of age. Cellular accretion of protein and other solids was estimated to account for at least 90% of the observed weight gain. We calculated K+ concentration in both the NB and adult to be approximately 115 mEq/L cell water. Thus, postnatal maturation of the mid-CCT is characterized by surges in cell volume, dry weight, and K+ content after the first month of life. The rise in K+/cell reflects primarily enhanced protein binding rather than addition of free cytosolic K+. The increase in CCT diameter (27.4 ± 0.5 to 33.9 ± 0.4 μm; p < 0.05) results from cell hypertrophy. Since there was no change in the number of cells/mm tubular length, axial growth of the CCT (3-fold) must occur by hyperplasia, probably in the superficial cortex. CCT growth may follow the postnatal surge in SNGFR and the opening of newly functioning superficial nephrons.
An 8–16 GHz SiGe Low Noise Amplifier With Performance Tuning Capability for Mitigation of Radiation-Induced Performance Loss

We present a wideband, low noise amplifier (LNA) implemented in a Silicon-Germanium Heterojunction Bipolar Transistor (SiGe HBT) technology. This SiGe LNA covers a frequency range of 8-16 GHz and achieves a peak gain of 17.5 dB at nominal bias and a peak OIP3 of 15.8 dBm at 10 GHz at nominal bias. The noise figure (NF) of the LNA is 4.5-8.1 dB across band, and it nominally consumes 4 mA from a 4 V supply. Samples were irradiated with 63.3 MeV protons to proton-equivalent doses ranging from 200 krad(Si) to 2 Mrad(Si). This LNA incorporates bias control “tuning-knobs” to enable bias tuning to mitigate for RF performance loss due to total dose exposure and process variation in performance metrics. The effectiveness of the tuning “knobs” to compensate for lost post-irradiated performance was investigated. It was found that the LNA performance can be restored with the use of the tuning knobs with a performance tuning algorithm.
Appearance of a nocturnal peak of leptin secretion in the pubertal rat.

Whether leptin is involved in the timing of puberty remains highly controversial in the rat. Daytime leptin secretion shows little change during the transition into adulthood. Because leptin exhibits a diurnal variation in the adult, it is possible that the ontogeny of such a rhythm provides important information for the timing of puberty. To begin to evaluate this hypothesis, we determined the development of the diurnal leptin secretion in the rat. The young females were raised in a light-controlled environment (12L, 0700 h light on). A cannula was placed in the right atrium on the previous day, and blood samples were collected every 4 h on Days 21, 24, 28, 32, 36 (1 day after vaginal opening), and 48 (adult, diestrus of estrous cycle). In addition to vaginal opening, plasma prolactin levels were determined as an endocrine index of puberty. Changes in food intake were monitored because nocturnal food intake has been considered to be a synchronizer for the leptin rhythm. This pattern of food intake was clearly evident throughout the ages studied. By contrast, there was no leptin rhythm at 21 and 24 days of age. Beginning at 28 days, leptin secretion exhibited a significant nocturnal peak (2300 h); this nocturnal peak increased in amplitude at 32 and 36 days and was still apparent in the cycling adult at Day 48. Plasma prolactin did not exhibit a diurnal rhythm but it increased from Days 32 to 48. The present findings indicate that in the rat, both the appearance of the nocturnal leptin rhythm and the nocturnal increase in circulating leptin levels during development carry information for timing the onset of puberty.
The Evolution Of Circular Questions: Training Family Therapists

This article describes a procedure for training family therapists in the clinical application of circular questioning as developed and implemented at the Marriage and Family Therapy Clinic at the University of Iowa. A pragmatic taxonomy of circular questions is presented; instructional handouts designed to facilitate the use of these questions within the trainee's initial interviews are included.
Lifshitz transition in underdoped cuprates

Recent studies show that quantum oscillations thought to be associated with a density wave reconstructed Fermi surface disappear at a critical value of the doping for YBa{sub 2}Cu{sub 3}O{sub 6+y} and the cyclotron mass diverges as the critical value is approached from the high doping side. We argue that the phenomenon is due to a Lifshitz transition where the pockets giving rise to the quantum oscillations connect to form an open (quasi-one-dimensional) Fermi surface. The estimated critical doping is close to that found by experiment and the theory predicts a logarithmic divergence of the cyclotron mass with a coefficient comparable to that observed in experiment.
The comparative roles of home and host supervisors in the expatriate experience

This study investigates the impact of home and host supervisors on expatriate success. Using survey and archival data on 206 expatriates of a large U.S. professional services firm, we hypothesize that high-quality leader-member exchange (LMX) relationships with home and host supervisors have different outcomes. Relationships with host-country supervisors have greater influence on in-country and short-term outcomes, including adjustment and intentions to complete the assignment. Home-country supervisors, on the other hand, have a greater influence over expatriates' subjective fit with their jobs and longer-term perceptions of how the overseas assignment will impact their career. Using a separate survey of home and host supervisors at the same firm, we found that one reason that home and host supervisors infl uence expatriates differently may be because home supervisors are more likely to see professional development as a goal for expatriate assignments. © 2009 Wiley Periodicals, Inc.
Stability of Some Hypothesized Psychological Determinants of Fertility Control

Ratings of Self-Status International, a scale designed to measure behavioral and attitudinal correlates of fertility control, was administered to 95 undergraduates on two occasions four weeks apart to estimate the stability of the 12 measured factors. The test-retest correlation of scores from the two times was .58. Ten of the 12 factor scores had estimates of stability ranging between .48 and .69, but two factors yielded coefficients of .23 (p < .05) and .32 (p < .01) only, indicating need for revision or reformulation.
Wave energy in white dwarf atmospheres. I - Magnetohydrodynamic energy spectra for homogeneous DB and layered DA stars

The radiative damping of acoustic and MHD waves that propagate through white dwarf photospheric layers is studied, and other damping processes that may be important for the propagation of the MHD waves are calculated. The amount of energy remaining after the damping processes have occurred in different types of waves is estimated. The results show that lower acoustic fluxes should be expected in layered DA and homogeneous DB white dwarfs than had previously been estimated. Acoustic emission manifests itself in an enhancement of the quadrupole term, but this term may become comparable to or even lower than the dipole term for cool white dwarfs. Energy carried by the acoustic waves is significantly dissipated in deep photospheric layers, mainly because of radiative damping. Acoustically heated corona cannot exist around DA and DB white dwarfs in a range T(eff) = 10,000-30,000 K and for log g = 7 and 8. However, relatively hot and massive white dwarfs could be exceptions.
SELF-MONITORING AND IMAGE APPEALS IN ADVERTISING

Two studies with samples of young adults (n = 130 and n = 168) were conducted to examine the effect of self-monitoring and susceptibility to interpersonal influence on preferences for image-oriente...
The effect of instruction and feedback in the development of pragmatic competence

Abstract This study examines the effectiveness of teaching pragmatic information through the use of explicit or implicit pre-instruction, and explicit or implicit feedback, to English-speaking learners of third-semester Spanish. Results on a pretest, posttest, and delayed posttest indicate that the groups that experienced explicit pre-instruction and explicit feedback during exercises performed significantly better than the other experimental group and the control group in multiple choice items. The group that had implicit instruction together with implicit feedback performed significantly better in the open-ended dialogues, suggesting that the question recasts used had a positive effect on their pragmatic production. The delayed posttest, however, revealed that such gains are not clearly retained in the longer term. Nevertheless, the two posttests indicate that those groups that received instruction and feedback, whether explicit or implicit, appear to become aware of a greater number of options to express suggestions, and also of a need for pragmatic mitigation, more quickly than the control group. These findings are encouraging for the use of pragmatic instruction in the classroom to develop a greater pragmatic competence.
Stochastic study of the effect of ionic strength on noncovalent interactions in protein pores.

Salt plays a critical role in the physiological activities of cells. We show that ionic strength significantly affects the kinetics of noncovalent interactions in protein channels, as observed in stochastic studies of the transfer of various analytes through pores of wild-type and mutant α-hemolysin proteins. As the ionic strength increased, the association rate constant of electrostatic interactions was accelerated, whereas those of both hydrophobic and aromatic interactions were retarded. Dramatic decreases in the dissociation rate constants, and thus increases in the overall reaction formation constants, were observed for all noncovalent interactions studied. The results suggest that with the increase of salt concentration, the streaming potentials for all the protein pores decrease, whereas the preferential selectivities of the pores for either cations or anions drop. Furthermore, results also show that the salt effect on the rate of association of analytes to a pore differs significantly depending on the nature of the noncovalent interactions occurring in the protein channel. In addition to providing new insights into the nature of analyte-protein pore interactions, the salt-dependence of noncovalent interactions in protein pores observed provides a useful means to greatly enhance the sensitivity of the nanopore, which may find useful application in stochastic sensing.
Desiccation as a long-term survival mechanism for the archaeon Methanosarcina barkeri.

ABSTRACT Viable methanogens have been detected in dry, aerobic environments such as dry reservoir sediment, dry rice paddies and aerobic desert soils, which suggests that methanogens have mechanisms for long-term survival in a desiccated state. In this study, we quantified the survival rates of the methanogenic archaeon Methanosarcina barkeri after desiccation under conditions equivalent to the driest environments on Earth and subsequent exposure to different stress factors. There was no significant loss of viability after desiccation for 28 days for cells grown with either hydrogen or the methylotrophic substrates, but recovery was affected by growth phase, with cells desiccated during the stationary phase of growth having a higher rate of recovery after desiccation. Synthesis of methanosarcinal extracellular polysaccharide (EPS) significantly increased the viability of desiccated cells under both anaerobic and aerobic conditions compared with that of non-EPS-synthesizing cells. Desiccated M. barkeri exposed to air at room temperature did not lose significant viability after 28 days, and exposure of M. barkeri to air after desiccation appeared to improve the recovery of viable cells compared with that of desiccated cells that were never exposed to air. Desiccated M. barkeri was more resistant to higher temperatures, and although resistance to oxidative conditions such as ozone and ionizing radiation was not as robust as in other desiccation-resistant microorganisms, the protection mechanisms are likely adequate to maintain cell viability during periodic exposure events. The results of this study demonstrate that after desiccation M. barkeri has the innate capability to survive extended periods of exposure to air and lethal temperatures.