cssi/SciSciGPT-SciSciNet huggingface dataset:
Thermal decarboxylation of acetic acid: Implications for origin of natural gas

Abstract Laboratory experiments on the thermal decarboxylation of solutions of acetic acid at 200°C and 300°C were carried out in hydrothermal equipment allowing for on-line sampling of both the gas and liquid phases for chemical and stable-carbon-isotope analyses. The solutions had ambient pH values between 2.5 and 7.1; pH values and the concentrations of the various acetate species at the conditions of the experiments were computed using a chemical model. Results show that the concentrations of acetic acid, and not total acetate in solution, control the reaction rates which follow a first order equation based on decreasing concentrations of acetic acid with time. The decarboxylation rates at 200°C (1.81 × 10−8 per second) and 300°C (8.17 × 10−8 per second) and the extrapolated rates at lower temperatures are relatively high. The activation energy of decarboxylation is only 8.1 kcal/mole. These high decarboxylation rates, together with the distribution of short-chained aliphatic acid anions in formation waters, support the hypothesis that acid anions are precursors for an important portion of natural gas. Results of the δ13C values of CO2, CH4, and total acetate show a reasonably constant fractionation factor of about 20 permil between CO2 and CH4 at 300°C. The δ13C values of CO2 and CH4 are initially low and become higher as decarboxylation increases.
STAPHYLOCOCCUS AUREUS MENINGITIS IN A PATIENT WITH ACQUIRED IMMUNODEFICIENCY SYNDROME

Meningitis due to Staphylococcus aureus is well described but uncommon. Most cases arise as a complication of neurosurgical interventions or head trauma, although some arise spontaneously. To our knowledge, no case of S. aureus meningitis has been previously reported in a person with the acquired immunodeficiency syndrome (AIDS). Herein we describe a case of S. aureus meningitis in a person with AIDS who had no history of a neurosurgical procedure, head trauma, or overwhelming bacteremia. Treatment of this infection was successful. S. aureus should be added to the list of potential pathogens that can cause spontaneous meningitis in people with AIDS.
Integrated analysis of microRNAs and their disease related targets in the brain of mice infected with West Nile virus

To determine whether cellular miRNAs play a role in West Nile virus (WNV) neuropathogenesis, we evaluated WNV-infected mice brain for the expression profile of miRNAs, their potential functions and their correlation with genes involved in inflammatory pathways. A total of 528 miRNAs and 168 mRNA genes were examined. One hundred thirty-nine miRNAs were significantly differentially expressed in WNV-infected mice brain. Ingenuity pathway analysis demonstrated that these miRNAs and their target genes are involved in pathways related to inflammatory response, immune-cell trafficking and cell death. Moreover, we demonstrate an inverse correlation between WNV-modulated miRNAs and their target neuroinflammatory genes in the same mice brain. We demonstrate that miR-196a, miR-202-3p, miR-449c, and miR-125a-3p target multiple genes involving cytokines, chemokines, and apoptotic genes, which belong to different signaling pathways that play critical role in WNV neuropathogenesis. Functional studies targeting specific miRNA are warranted to develop therapeutics for the management of WNV disease.
Careers of Ph.D.'s in the Biosciences

Since 1920, over a quarter million earned Ph.D.'s have been awarded in the United States. Of these, about 46,000 were in the biosciences, including agriculture and health-related fields. The actual number of Ph.D.'s awarded annually in biosciences has risen from an annual average of 237 for the 1920's to 2320 for the 1960's, a tenfold increase, as shown in Figure 1. In the 1920's one out of five Ph.D.'s was in bioscience. The proportion has gradually dropped so that in the 1960's only one in six Ph.D.'s has been bioscience. This shift in proportion is the result of especially rapid growth in the number of Ph.D.'s granted in engineering and education in recent years. There have been some interesting shifts in the proportion of Ph.D.'s awarded in the subfields of bioscience over the years. These are illustrated in Figure 2 for the 1920's and the 1960's. Agriculture and biochemistry have grown quite rapidly; in the 1920's each of these fields accounted for 10% of the Ph.D.'s, but in recent years agriculture has come to represent over 20% and biochemistry 15% of the bioscience Ph.D.'s. Microbiology represents a slightly larger percentage than it did in the 1920's, while the proportions in physiology and the health-related fields are relatively unchanged. The general fields of zoology and botany have come to represent a smaller proportion than they did in the 1920's, reflecting a trend toward greater specialization. The contents of the "other" category which includes a variety of small fields and new fields has changed over the years. For the 1960's almost one-third of the group are geneticists. Two major published reports, one compiled by Harmon and Soldz (1963), and the other edited by Boercker (1967), provide further information on Ph.D.'s granted by U.S. universities.
1H, 13C, and 15N chemical shift assignments for PfPMT, a phosphoethanolamine methyltransferase from Plasmodium falciparum

Phosphoethanolamine methyltransferases (PMTs also known as PEAMTs) catalyze the three-step s-adenosyl-methionione-dependent methylation of phosphoethanolamine to form phosphocholine. These enzymes play an important function in the synthesis of phosphatidylcholine, the major phospholipid in the membranes of lower and higher eukaryotes, as well as in the production of the compatible solute and osmoprotectant glycine betaine in plants. Genetic studies in plants, Caenhorhabditis elegans and Plasmodium falciparum have demonstrated that disruption of PMT activity results in severe defects in important cellular processes such as development, replication, survival and sexual maturation and differentiation. Here we report chemical shift assignments for PfPMT, the PMT from Plasmodium falciparum. X-ray crystal structures have been recently reported for complexes of PfPMT, but the structure of the apoenzyme remains unknown. The solution structure of the apoenzyme will help to elucidate important details of the mechanism of substrate binding by PfPMT, as residues comprising the substrate binding site are inaccessible to solvent in the conformation evident in the available crystal structures. In addition to enabling determination of the solution structure of the apoenzyme, the assignments will facilitate additional investigations into the interaction of PfPMT with its substrates and inhibitors.
Accelerators for pion clinical facilities

Abstract Negative pi-mesons are a unique particle type with possible application to cancer radiation therapy. In the Fall of 1975, a panel was formed under the auspices of the Stanford University Medical Center and chaired by Dr. John Blewett, Brookhaven National Laboratory, to investigate the current state-of-the-art in accelerator technology applicable to pi-meson producing facilities. Representatives from several laboratories with active accelerator research programs participated in this panel. All known accelerator types were considered, and rough cost estimates compared. The opinion of the members of this panel was that for the short term, a high-current electron linac might be the most logical choke for pion production, but that the proton Linear accelerator, as being developed at the Los Alamos Scientific Laboratory, was clearly the optimum choice for a long-term development of hospital-based facilities.
IPV6 features for enhancing QoS in the GIG

The design of the IPv6 protocol includes mechanisms that fix issues encountered in IPv4 networks and provides new features and capabilities. Many of these features enhance the end-to-end performance of converged IP-based networks, and QoS improvements are usually listed as a major advantage of IPv6. This paper reviews IPv6-based QoS-enabling mechanisms and provides various examples of how they can be used in the GIG, including some innovative approaches
Nephrotoxicity of cephalosporin antibiotics in experimental animals.

To delineate the site and morphology of renal lesions produced by cephalosporin antibiotics, rabbits and rats were treated with various doses of either cephalothin, cephaloridine, or cefazolin. In rabbits, a single 200 mg/kg injection of cephaloridine, administered in a previous study conducted in our laboratory, resulted in renal tubular necrosis in each of six animals treated, whereas in the present study, 500 mg of cefazolin/kg caused less extensive lesions and not in all rabbits. In rats treated with 250 mg of cephaloridine/kg per day for 28 days, two of 40 developed tubular injury, whereas no lesions were observed by light microscopy in rats treated with cephalothin or cefazolin. A daily dosage of 1,100 mg of cephalothin/kg administered to rats for 28 days produced no renal lesions; abnormalities were observed in the tubules after treatment with cephaloridine and cefazolin. When 2,200 mg of cephaloridine/kg was administered daily to rats for only five days, all developed massive tubular necrosis, whereas treatment with cephalothin and cefazolin resulted in only subtle abnormalities. These data demonstrate that cephaloridine produces a dose-dependent lesion of the proximal renal tubule in the rabbit and rat. The lesions produced by cefazolin are less marked, and only subtle changes are observed with cephalothin. The use of cephalosporin antibiotics in clinical practice has been purported to carry with it the hazard of nephrotoxicity. Several authors have reported acute tubular necrosis following the use of cephaloridine [1-3], and cephalothin also has been incriminated to a lesser extent in the production of injury to renal tubules [4, 5]. The present study compares the potential for nephrotoxicity of three cephalosporin antibiotics, cephalothin, cephaloridine and cefazolin, in experiments involving both short- and long-term therapy. In a previous report from this laboratory [6], fixation of renal tissue by intravascular perfusion was employed to define early and subtle changes in renal tubules caused by cephaloridine. The same technique, utilized in the present series of experiments, permitted detailed examination of renal tubules and avoided the artifacts produced during fixation by immersion procedures. This
Rocket Science for Educators; K-12 Techniques for Science Technology Engineering and Mathematics

The Wisconsin AIAA chapter has leveraged the talent of its members to provide a variety of outreach opportunities for precollege aged students. Hands-on demonstrations, visual aids, and real-life space flight examples provide a foundation for bringing pre-college aged students face-to-face with space-related science, designed hardware, technology, and potential benefits; increased interest in aerospace and space related fields that lead to study at the university level followed by career. The Rocket Science for Educators program consists of a workshop used to assist schools in implementing rocket science into respective math or science curriculums. Participating educators attend a weekend workshop and receive a set of rocket science materials that they may take back to their respective schools. This workshop is taught by aerospace professionals where they provide a unique opportunity for teachers to provide meaningful activities in their classrooms and improve student performance in the fields of science, technology, engineering, and mathematics.
THROMBOXANE AND PROSTACYCLIN RELEASE AFTER ENDOTOXIN INFUSION IN THE RAT

To determine in the rat whether pulmonary artery hypertension accompanies thromboxane release, we sequentially monitored pulmonary and systemic artery pressures and cardiac output. We measured pulmonary and aortic plasma levels of TxB2 as well as 6-keto-prostaglandin F1α (6-keto-PGF1α) in awake unrestrained adult male Sprague-Dawley rats given a single infusion of endotoxin at the relatively high dose commonly administered to this endotoxin-resistant species. At 40 min after endotoxin infusion, both pulmonary and aortic TxB2 and 6-keto-PGF1α levels increased nine-fold and seven-fold above baseline, respectively. In the pulmonary artery, 40 min after infusion, both mediator levels differed significantly from baseline (p<0.05), whereas in the aorta, because of marked variance in the response of different animals, only the 6-keto-PGF1α levels achieved significance (p<0.05). These changes were associated with a fall in systemic blood pressure and cardiac output, but no demonstrable rise in pulmonary artery pressure (PAP). Despite ultrastructural evidence of vascular injury, these data indicate that in the rat thromboxane and prostacyclin release following a single infusion of endotoxin is not associated with pulmonary hypertension and that increased prostacyclin production may contribute to systemic hypotension.
Political science: academic virtual conferencing—the case of the teaching politics virtual conference

This article examines virtual conferencing as an alternative to the traditional academic conference. After defining terms and reviewing the purposes of academic conferences, the article looks at virtual conferencing in three ways. The first is the differences between virtual conferencing and traditional conferencing. The second is the primary trade-offs to be considered in planning a virtual conference. The third is a case study of the Teaching Politics Virtual Conference.
Experimental and textural constraints on mafic enclave formation in volcanic rocks

Abstract We have used experiments and textural analysis to investigate the process of enclave formation during magma mixing at Southwest Trident volcano, Alaska. Andesite enclaves are present throughout the four dacite lava flows produced by the eruption, and resemble mafic enclaves commonly found in other volcanic rocks. Our experiments replicate the pressure–temperature–time path taken by enclave-forming andesite magma as it is engulfed in dacite during magma mixing. Pressure and temperature information for the andesite and dacite are from [Coombs et al., Contrib. Mineral. Petrol. 140 (2000) 99–118]. The andesite was annealed at 1000°C, and then cooled to 890°C at rates of 110°C h−1, 10°C h−1, and 2°C h−1. Once cooled to 890°C, andesite was held at this lower temperature from times ranging from 1 to 40 h. The andesite that was cooled at the slower rates of 2°C h−1 and 10°C h−1 most resembles enclave groundmass texturally and compositionally. Based on simple thermal calculations, these rates are more consistent with cooling of the andesite groundmass below an andesite–dacite interface than with cooling of enclave-sized spheres. If enclaves do crystallize as spheres, post-crystallization disaggregation must occur. Calculations using the MELTS algorithm [Ghiorso and Sack, Contrib. Mineral. Petrol. 119 (1995) 197–212] show that for incoming andesite to become less dense than the dacite ∼34 volume % of its groundmass must crystallize to undergo ∼18 volume % vesiculation; these values are similar to those determined for Southwest Trident enclaves. Thus such crystallization may lead to ‘flotation’ of enclaves and be a viable mechanism for enclave formation and dispersal. The residual melt in the cooling experiments did not evolve to rhyolitic compositions such as seen in natural enclaves due to a lack of a decompression step in the experiments. Decompression experiments on Southwest Trident dacite suggest an average ascent rate for the eruption of ∼2–3 MPa h−1. An andesite experiment that was cooled and then decompressed at this rate contains melt that matches that of the natural enclaves. It is apparent that decompression (ascent)-induced crystallization occurs in enclaves, but not in the form of microlites as happens in the dacite host, due either to insufficient residence time at chamber temperatures or to the pre-existing microphenocrysts which act as sites for new growth.
The interaction of uranyl chloride with hydrazine, ammonia and amines

Abstract Solid systems of composition UO2Cl2·4H2H4, UO2Cl2·3NH3 and UO2Cl2·23RHN2 (R = CH3, C2H5, C3H7, and C4H9) were prepared. Of these only UO2Cl2·3NH3 is stable up to 200°. The UO2Cl2-RNH2 systems underwent a slow redox reaction giving UO2, ligand hydrochloride and polymeric materials as the solid products. The polymeric materials containing carbon, nitrogen and hydrogen appeared to be primarily polymers of alkyl imine, produced from the corresponding amine by dehydrogenation. In UO2Cl2-n- and i-butylamine systems the amine also seems to be involved in the polymerization. In the UO2Cl2-t-butylamine redox reaction, isobutylene and a branched hexane or hexene were identified in the volatile products. The only oxidation products in the UO2Cl2N2H4 system were non-condensable gases (N2 and H2). Aqueous 10 M hydrazine was found to reduce solid UO2Cl2, but not UO3, to solid UO2 at room temperature.
The role of natural-enemy escape in a gallmaker host-plant shift

The successful colonization of novel host-plant species by herbivorous insects may be facilitated by a reduction in natural-enemy attack on insect populations associated with the novel (derived) host plant. This is particularly true if natural enemies use host-plant or habitat cues in searching for their herbivore prey. In order to test whether the acquisition of enemy-free space could have influenced the host shift in the goldenrod ball gallmaker, Eurosta solidaginis, we estimated levels of natural-enemy attack in 25 host-race populations associated with Solidago altissima and S. gigantea (Compositae) spanning the zone of sympatry between S. altissima and S. gigantea host races in New England. Mortality due to attack by the parasitoid wasp Eurytoma obtusiventris was significantly higher for the ancestral than for the derived host race (30.5% versus 0.4%) across the transect, which is consistent with the enemy escape hypothesis. Contrary to this hypothesis, mordellid beetles caused significantly higher mortality on the derived than ancestral host race (17.1% versus 2.6%). Mortality by a second parasitoid wasp and birds showed no significant differences between the two host races. Overall, the derived host race had significantly higher survivorship across the transect (36.6% versus 20.8%). An analysis of survivorship and parasitoid mortality levels from sympatric sites in this study and previous studies showed a highly significant correlation between the levels of Eurytoma obtusiventris attack and the survivorship advantage of the derived host race. Observations of this parasitoid's searching behavior confirmed that it preferentially searches the ancestral host for fly larvae. Current patterns of host-race mortality and naturalenemy behavior and abundance are consistent with the facilitation of the host shift by escape from a specialist parasitoid.
Sensitive and specific colorimetric dot assay to detect eastern equine encephalomyelitis viral RNA in mosquitoes (Diptera: Culicidae) after polymerase chain reaction amplification.

A sensitive and specific colorimetric dot assay following polymerase chain reaction (PCR) method has been developed to detect 0.1 pg of eastern equine encephalomyelitis viral (EEEV) RNA. The assay is 250-fold more sensitive than analysis by electrophoresis and is based on converting a 291-nucleotide sequence of the viral coat protein amino terminus into a double-stranded DNA (dsDNA) and amplifying the DNA using a specific primer pair and PCR. The amplified complementary DNA (cDNA) is denatured, adsorbed onto a nylon strip, baked, and detected with a digoxigenin-labeled probe. Dots with viral cDNA are stained dark red, whereas controls do not stain or stain lightly. The assay is very specific and sensitive and detects only EEEV. RNA of Venezuelan equine encephalitis, St. Louis encephalitis, Keystone, Flanders, Tensaw, and western equine encephalitis viruses were not detected. EEEV (Ten Broeck) RNA was detected at the 10-ng level, indicating that the prototype we used may have different nucleotides in the region where the primer pair binds. The PCR amplified EEEV cDNA that was 92% homologous to the consensus sequence of EEEV. The detection of EEEV in the liver of an infected Emu bird and in field-collected mosquitoes from Florida and Massachusetts that were analyzed concurrently as blind samples by tissue culture plaque assay and by PCR dot analysis proved that the assay is sensitive and can be used to detect infected mosquitoes. The assay can detect at least 1 infected mosquito in a pool of 1,000 uninfected mosquitoes.
Differences in response of two model estuarine crustaceans after lethal and sublethal exposures to chlorpyrifos.

This study assessed the in vitro and in vivo effects of an acetylcholinesterase enzyme inhibitor (chlorpyrifos) in two estuarine crustaceans: grass shrimp (Palaemonetes pugio) and mysid (Americamysis bahia). The differences in response were quantified after lethal and sublethal exposures to chlorpyrifos and in vitro assays with chlorpyrifos-oxon. Results from the in vitro experiments indicated that the target enzyme, acetylcholinesterase (AChE), in the two species was similar in sensitivity to chlorpyrifos inhibition with IC50s of 0.98 nM and 0.89 nM for grass shrimp and mysids, respectively. In vivo experiments showed that mysids were significantly more sensitive to chlorpyrifos-induced AChE inhibition after 24 h of exposure. The in vivo EC50s for AChE inhibition were 1.23 μg L−1 for grass shrimp and 0.027 μg L−1 for mysids. Median lethal concentrations (24h LC50 values) were 1.06 μg L−1 for grass shrimp and 0.068 μg L−1 for mysids. The results suggest that differences in the response of these two crusta...
Brillouin scattering from supercooled adsorbates

Abstract Brillouin scattering is used as a sensitive probe of structural properties of gases adsorbed on porous glass. Evidence is seen for extensive supercooling behavior in both oxygen and nitrogen.
Measurement of rotational diffusivity of rodlike molecules in amorphous polymer matrices by the dynamic kerr effect

Electrooptic (Kerr effect) relaxation experiments, designed to measure the rotational diffusivity of collagen (rodlike) molecules in aqueous poly(ethyleneoxide) (amorphous) semidilute solutions under various conditions have been performed. The experimental results have been compared with the predictions of a previously derived model giving the rotational diffusivity of dilute rods in semidilute amorphous polymer solutions as a function of rod length and amorphous polymer concentration. Excellent agreement is found between the predicted scaling Dr ∼ ϕL−7 (Dr = rod rotational diffusivity, pip = polymer weight fraction, and L = rod length) and the experiments.
Comparison of frequency doubling perimetry with humphrey visual field analysis in a glaucoma practice.

Abstract PURPOSE: To determine the sensitivity and specificity of frequency doubling perimetry with Humphrey visual field testing used as the gold standard. METHODS: Frequency doubling perimetry and Humphrey visual field testing (24-2) were performed on 29 consecutive patients in a glaucoma practice. Data for the right eye were used to calculate sensitivity, specificity, and receiver operating characteristic curves. RESULTS: For the frequency doubling perimetry in screening mode, and with an abnormal glaucoma hemifield test used as the gold standard, the area under the receiver operating characteristic curve was 89.3%, 81.5%, or 75.0% for the presence of mild, moderate, or severe relative defects, respectively. Similar results were found with the use of mean deviation ( P P CONCLUSIONS: Frequency doubling perimetry showed a high sensitivity and specificity for detecting visual field abnormalities, especially when threshold strategies were used.
Ion Hydration Stripping Kinetics Support Thyrofluidic Ion Channel Gating

The thyrofluidic model of ion channel entry gating has the membrane electric field at the ion channel pore entrance responsible for stripping ion hydration shells, selectively admitting ions into the pore for transport. Capillary electrophoresis studies have shown that full hydration stripping occurs at field strengths corresponding to distances of 6.5 to 8 nanometers from a membrane. This work considers the rate at which hydration stripping occurs relative to the rate of ion migration near the membrane.The free energy barrier for one water molecule to escape the first (inner) hydration shell of a Na+ ion has been calculated to be 9.5 kJ/mole, equivalent to a field strength of 118.75 V/cm. Mean lifetime of attachment of one water molecule bound to a Na+ ion has been calculated to be 5 ps. A linear model of the energy and time to strip 5 of the 6 water molecules from the first shell yields 47.5 kJ/mol (594 V/cm) and 25 ps. Modeling single molecule dissociation to have exponential decay yields 101.7 kJ/mol (1,270 V/cm) and 197 ps. Electric field dependent ion velocity changes occur between 200 and 600 V/cm, consistent with the linear model.The Einstein-Smoluchowski equation shows ions with radius 0.1 nm diffuse at 3.2 nm/ns. As a result, Na+ will diffuse 0.08 nm (linear) or 0.63 nm (exponential) after reaching a field of 594 or 1,270 V/cm, respectively, for complete hydration stripping, the latter occurring 7 nm from the membrane. To date, all known kosmotropic ion channel pore entrances sit within 2 nm of the membrane. Thus, the membrane electric field will strip the hydration shells from Na+ long before the ion can reach the pore entrance. As such, electric field hydration stripping kinetics are compatible with thyrofluidic channel gating.
Deductive cause-consequence analysis (DCCA)

Abstract In this paper we present a new form of formal safety analysis: deductive cause-consequence analysis (DCCA). Deductive Cause-Consequence Analysis is a way to use formal methods for safety analysis. It substitutes error-prone informal reasoning by mathematical proofs. DCCA allows to rigorously prove whether a failure on component level is the cause for system failure or not. DCCA is a formal generalization of the two most common safety analysis techniques: failure modes and effects analysis (FMEA) and fault tree analysis (FTA). We apply the method to a real world case study: the height control in the Elbe-tunnel in Hamburg. This shows how formal safety analysis with DCCA helps identifying design flaws and weaknesses in a real-world industrial system.
Tuberculosis Knowledge and Beliefs Among Prison Inmates and Lay Employees

Tuberculosis is a recognized health problem in United States' prisons and jails. To assess tuberculosis knowledge and beliefs among incarcerated persons and non-medical employees of correctional facilities, written questionnaires were administered to 456 individuals incarcerated in the Texas Department of Criminal Justice (TDCJ), 127 staff of TDCJ substance abuse felony punishment facilities (SAFPF), and 146 TDCJ correctional officers. Demographic information was collected also. For the 12 true/false knowledge questions asked of incarcerated persons and SAFPF staff, the number of correct responses ranged from 2-12 (mean=9. 16) among incarcerated individuals and from 4-12 (mean= 9.37) among SAFPF staff. Performance of these two groups was similar overall, but varied on certain questions. For correctional officers, who were asked 11 knowledge questions with possible responses of "agree," "disagree," and "don't know," the number of correct responses ranged from 1-11 (mean=6.70).The most common misconceptions...
Pervaporation-assisted esterification of lactic and succinic acids with downstream ester recovery

Abstract Reactors coupled with membrane separation, such as pervaporation, can help enhance the conversion of reactants for thermodynamically or kinetically limited reactions via selective removal of one or more product species from the reaction mixture. Esterification of lactic acid (C 3 H 6 O 3 ) and succinic acid (C 4 H 6 O 4 ) with ethanol (C 2 H 5 OH) to generate ethyl lactate (C 5 H 10 O 3 ) and diethyl succinate (C 8 H 14 O 4 ), respectively, is studied in well-mixed reactors with solid catalysts (Amberlyst XN-1010 and Nafion NR50) and two pervaporation membranes (GFT-1005 and T1-b) in this article. The results of catalyst compatibility and membrane stability studies are discussed. Experiments with a closed-loop system of a “batch” catalytic reactor and a pervaporation unit employing GFT-1005 reveal that for esterification of both lactic and succinic acids, fractional conversions of the two reactants exceeding the corresponding maximum values in a reaction-only operation and close to unity are obtained by stripping water, a reaction product. The kinetics of pervaporation is studied to obtain a working correlation for the flux of water in terms of temperature and water concentration on the feed side of the pervaporator. The efficacy of pervaporation-aided esterification is illustrated by attainment of near total utilization of the stoichiometrically limiting reactant within a reasonable time. Protocols for recovery of ethyl lactate and diethyl succinate from pervaporation retentate are discussed and simultaneous esterification of lactic and succinic acids, which is an attractive and novel concept, is proposed.
A New Genus of Dufoureine Bee from Texas (Hymenoptera: Halictidae)

A new genus and species, Michenerula beameri (Halictidae, Dufoureinae), are described from western Texas.
Pathologic findings in familial exudative vitreoretinopathy

• Two patients with familial exudative vitreoretinopathy were seen by us, and the clinical features of their condition are reviewed herein. The pathologic findings of both patients showed a prominent vitreous membrane posterior to the ora serrata. To our knowledge, this finding, as well as multiple secondary changes in the retina and the anterior segment, has not been previously described.
Thermo-mechanical extrusion pretreatment for conversion of soybean hulls to fermentable sugars.

Thermo-mechanical extrusion pretreatment for lignocellulosic biomass was investigated using soybean hulls as the substrate. The enzyme cocktail used to hydrolyze pretreated soybean hulls to fermentable sugars was optimized using response surface methodology (RSM). Structural changes in substrate and sugar yields from thermo-mechanical processing were compared with two traditional pretreatment methods that utilized dilute acid (1% sulfuric acid) and alkali (1% sodium hydroxide). Extrusion processing parameters (barrel temperature, in-barrel moisture, screw speed) and processing aids (starch, ethylene glycol) were studied with respect to reducing sugar and glucose yields. The conditions resulting in the highest cellulose to glucose conversion (95%) were screw speed 350 rpm, maximum barrel temperature 80 °C and in-barrel moisture content 40% wb. Compared with untreated soybean hulls, glucose yield from enzymatic hydrolysis of soybean hulls increased by 69.6%, 128.7% and 132.2%, respectively, when pretreated with dilute acid, alkali and extrusion.
Surgery with intraoperative radiotherapy for sarcomas of the pelvic girdle: a pilot experience.

Abstract Sarcomas of the pelvic girdle represent difficult treatment problems. Many are not treatable for cure, and among the patients who are technically resectable, there is high risk for local tumor recurrence and distant spread. Intraoperative radiotherapy (IORT) has been used in conjunction with surgical resection in five patients with extensive sarcomas of the pelvic girdle. Patients underwent a hemipelvectomy and IORT (dose 20–30 Gy) to the sacral resection margin and surrounding soft tissues. Three patients developed pulmonary metastases within 3 months and eventually died from metastastic disease (8–38 months). Two patients have remained disease-free (43 and 53 months). Four patients (80%) have remained locally free of tumor with follow-ups of 8–53 months. The only treatment complication was late osteonecrosis of the coccyx which appeared 7 months after treatment. By contrast, six historical control patients with sarcomas of the pelvic girdle treated with resection alone showed a local control rate of only 27% over a 40-month follow-up. On the basis of this preliminary experience, it appears that IORT may substantially help to control local disease in patients with grossly resectable sarcomas of the bony pelvis.
A comparative analysis of some aspects of the training and visit system of agricultural extension in India

The article utilises recent farm survey data to assess the performance of the Training and Visit Extension system in one district in the state of Haryana (India) compared to a neighbouring district covered by an older extension system. The data show a significantly higher level of village‐level extension activity in the area covered by Training and Visit Extension, and this is compatible with the large number of staff and higher expenditure on extension under this system. The data also suggest that knowledge of improved practices, especially in wheat cultivation, diffused faster in the area covered by T & V extension.
Identification, cloning, and expression of the CAMP factor gene (cfa) of group A streptococci.

The CAMP reaction is a synergistic lysis of erythrocytes by the interaction of an extracellular protein (CAMP factor) produced by some streptococcal species with the Staphylococcus aureus sphingomyelinase C (beta-toxin). Group A streptococci (GAS [Streptococcus pyogenes]) have been long considered CAMP negative, and this reaction commonly has been used to distinguish GAS from Streptococcus agalactiae. We here provide evidence that GAS possess this gene and produce an extracellular CAMP factor capable of participating in a positive CAMP reaction. The S. pyogenes CAMP factor is specified by a 774-bp open reading frame homologous to the CAMP factor genes from S. agalactiae and Streptococcus uberis. This gene, designated cfa, was isolated on a 1,256-bp fragment and cloned in Escherichia coli. Recombinant clones of E. coli expressing cfa secreted an active CAMP factor. The deduced 28.5-kDa protein encoded by cfa consists of 257 amino acids, with a predicted 28-amino-acid signal peptide. The cfa gene is widely spread among GAS: 82 of 100 clinical GAS isolates produced a positive CAMP reaction. Of the CAMP-negative strains, 17 of the 18 GAS strains contained the cfa gene. Additionally, CAMP activity was detected in streptococci from serogroups C, M, P, R, and U. The cfa gene was cloned and actively expressed in Escherichia coli and gene fusions were made, placing the β-galactosidase gene (lacZ) under control of the cfa promoter. These cfa promoter-lacZ fusions were introduced into S. pyogenes via a bacteriophage-derived site-specific integration vector where they showed that the cfa gene has a strong promoter that may be subject to as-yet-unidentified regulatory factors. The results presented here, along with previous reports, indicate that the CAMP factor gene is fairly widespread among streptococci, being present at least in groups A, B, C, G, M, P, R, and U.
Isolation of gonadal mutations in adult zebrafish from a chemical mutagenesis screen.

A mutagenesis screen was conducted on zebrafish using Nethyl N-nitrosourea as a mutagen and an F2 crossing scheme to obtain homozygous mutants in the F3 generation. Whole abdomens of 3-mo-old F3 zebrafish progeny were fixed and massembedded in paraffin blocks. Blocks were cut with a microtome to obtain cross-sections of the entire body cavity that included the ovaries and testes. Slides of the cross-sections were analyzed for alterations in gonadal structure and gametogenesis and were compared with gonads of wild-type fish. A total of 125 mutagenized genomes in 81 families were screened and 11 mutations were observed that produced visible phenotypes in only one sex per family. Male mutations included testes without mature sperm that contained either predominantly spermatocytes or spermatogonia. Female mutations included ovaries containing 1) degenerating oocytes surrounded by hypertrophied follicle walls or stroma, 2) extrafollicular tissue proliferation, 3) proliferating postovulatory follicle walls, and 4) large numbers of degenerating preovulatory and postovulatory oocytes. While past screens on zebrafish have concentrated on early developmental mutations, the results of this study demonstrate for the first time that mutagenesis can be used with zebrafish to study reproduction in adult animals. follicle, gamete biology, ovary, ovum, sperm, testis
Multi-objective optimization using genetic algorithm: Applications to imperfect preventive maintenance model

In this study, a multi-objective hybrid genetic algorithm (MOHGA) is proposed to optimize a multi-objective imperfect preventive maintenance (MOIPM) model. The MOHGA proposed not only utilizes a Pareto-based technique to determine and retain the superior chromosomes as the GA chromosome evolutions are performed, but also guides their search direction. In order to obtain diverse non-dominated solutions that approach the optimized Pareto-efficient frontier, the closeness metric and diversity metric are employed to evaluate the superiority of the non-dominated solutions. Accordingly, decision makers can easily determine the most appropriate maintenance alternative to constitute a maintenance strategy from the optimized non-dominated solutions, given the practical requirements of system performance under the constraints of maintenance resources. Furthermore, this study employs response surface methodology via systematic parameter experiments to determine the best search parameter settings in the MOHGA proposed. A simulated case verifies the efficacy and practicality of the MOHGA.
Islands of Difference: Design, Urbanism, and Sustainable Tourism in the Anthropocene Caribbean

Resumen Este articulo introduce la idea del antropoceno como un espacio problema con importancia para la antropologia del caribe y la industria turistica de este. Este termino es utilizado por cientificos para definir la era presente en la cual los procesos humanos operan al nivel de escala geologica y biologica en la tierra, y ha venido a justificar una gran cantidad de acciones en el nombre de la sostenibilidad. A traves de la examinacion de una zona dedicada a la construccion de segundos hogares en las Bahamas, identifico cambios en diseno turistico de la isla que va dejando atras el modelo del resort como enclave del turismo en masa. Argumento que las nociones de sostenibilidad del antropoceno no solo re-articulan las practicas de construccion y el “branding” del destino turistico, pero tambien las posibilidades analiticas para el estudio de fabricacion de lugar y procesos transnacionales. Abogo por una mayor incorporacion de la antropologia del diseno y urbana en el estudio del turismo al caribe como una forma de mejor entender estos eventos emergentes.
Current Concepts Review - The Healing and Regeneration of Articular Cartilage*

It is well established that damaged articular cartilage has a very limited potential for healing, and articular defects larger than two to four millimeters in diameter rarely heal even with such advances as the use of continuous passive motion26,36,70,98,101,128,130,138,162,163,208. Damage to articular cartilage is a common problem: in one study, it was associated with 16 percent (twenty-one) of 132 injuries of the knee that were sufficient to cause intra-articular bleeding88. Furthermore, damage to a joint surface can lead to premature arthritis128. Twyman et al. prospectively followed twenty-two knees in which osteochondritis dissecans had been diagnosed before skeletal maturity; at an average of thirty-four years, 32 percent had radiographic evidence of moderate or severe osteoarthritis235. Only 50 percent had a good or excellent functional result. Elderly patients (those who are sixty-five years of age or older) who have an arthritic condition can obtain dramatic relief from pain and restoration of function after total joint replacement. However, such procedures have higher rates of failure in young and early-middle-aged patients (those who are less than forty years old and those who are forty to sixty years old, respectively) than in elderly patients194. This leaves a large group of patients spanning a broad age-group, many of whom are in their prime, for whom there is no currently acceptable and reliable treatment. A typical example is that of a young, healthy individual who has arthrosis or osteochondritis dissecans following an injury to a joint. It might be possible to solve this patient's problems if the lost or damaged segment of articular cartilage inside the involved joint could be regenerated. After it had been restored, the …
Assessment of endothelium-mediated vasodilation of the peripheral circulation by transcutaneous ultrasonography and venous occlusion plethysmography

Transcutaneous ultrasonography is a noninvasive technique with the ability to measure the volumetric blood flow of the peripheral circulation. Peripheral blood flow can be determined by highresolution imaging of vessel diameter coupled with Doppler assessment of flow velocity. This method, however, has not been validated in vivo. Accordingly, brachial artery flow in response to intraarterial infusion of vasodilators was assessed by ultrasonography in 16 healthy subjects and compared to values obtained simultaneously by venous occlusion plethysmography. Blood flow calculated from ultrasound-derived vessel diameter and flow velocity was found to highly correlate with plethysmographic flow, withr values ranging from 0.83 to 0.99. Using this ultrasound technique combined with plethysmography, the response of conduit and resistance vessels to endothelium-mediated vasodilation was characterized. Doppler velocity rose dramatically with endothelium-dependent acetylcholine (970%), but only modestly with endothelium-independent vasodilators, nitroglycerin (292%) and nitroprusside (340%). Despite eliciting the greatest overall forearm flow response, acetylcholine resulted in a smaller increase in conduit diameter (15.4%) than nitroglycerin (21.8%), and only a comparable change than nitroprusside (14.6%). Taken together, these results suggest that acetylcholine acts predominantly on resistance vessels, whereas nitrovasodilators affect mainly conduit vessels. In summary, transcutaneous ultrasonography can be used reliably to assess flow changes in the peripheral circulation. Combined with plethysmography, this technique is useful for determining the relative contribution of conduit and resistance vessels to peripheral flow, particularly in the assessment of endothelium-mediated vasodilation.
Compact temperature compensation of inductive fly-back clamps for integrated power switches using a high-voltage base-current-compensated V be multiplier

In advanced power systems controlling inductive loads, integrating a power switch with clamping functionality that protects against inductive fly-back with other control circuitry can achieve a lower system cost. However, the conventional active clamp typically consists of many reverse-biased diodes that exhibit a positive temperature coefficient which is counterbalanced by several forward-biased diodes that consume a large chip area. A compact high-voltage V be multiplier with base-current compensation circuit is presented to introduce a negative temperature coefficient within the clamp that occupies 50% less chip area than an equivalent clamp compensated with forward-biased diodes. The active clamp along with an LDMOS power transistor and driving circuitry have been fabricated in an 180nm high-voltage BiCMOS process and measurement results show that a negative temperature coefficient was introduced to achieve a 4V reduction in clamping voltage over a −40oC to 160oC range.
Hypothesis: Septo-Optic Dysplasia Is a Vascular Disruption Sequence

Septo-optic dysplasia, a variable combination of absence of the septum pellucidum, optic nerve hypoplasia, and pituitary abnormalities, makes little embryologic sense: components arise from different tissues and processes at different times, it is seen often with porencephaly, which is asymmetric, and rarely with other midline findings, genetic causes are exceptional, and occasional absence of the pituitary stalk is developmentally anomalous. Vascular vulnerabilities of components, anatomical overlap with findings of hydranencephaly and porencephaly, and a decreased maternal age effect similar to that of other abnormalities with presumed vascular origins, suggest a vascular disruption sequence instead, possibly involving the proximal trunk of the anterior cerebral artery.
Synaptic scaling stabilizes persistent activity driven by asynchronous neurotransmitter release

Small networks of cultured hippocampal neurons respond to transient stimulation with rhythmic network activity reverberation that persists for several seconds, constituting an in vitro model of synchrony, working memory, and seizure. This mode of activity has been shown theoretically and experimentally to depend on asynchronous neurotransmitter release an essential feature of the developing hippocampus and is supported by a variety of developing neuronal networks despite variability in the size of populations 10--200 neurons and in patterns of synaptic connectivity. It has previously been reported in computational models that “small-world” connection topology is ideal for the propagation of similar modes of network activity, although this has been shown only for neurons utilizing synchronous phasic synaptic transmission. We investigated how topological constraints on synaptic connectivity could shape the stability of reverberations in small networks that also use asynchronous synaptic transmission. We found that reverberation duration in such networks was resistant to changes in topology and scaled poorly with network size. However, normalization of synaptic drive, by reducing the variance of synaptic input across neurons, stabilized reverberation in such networks. Our results thus suggest that the stability of both normal and pathological states in developing networks might be shaped by variance-normalizing constraints on synaptic drive. We offer an experimental prediction for the consequences of such regulation on the behavior of small networks.
A single GAL4 dimer can maximally activate transcription under physiological conditions

Abstract Most eukaryotic promoters contain multiple binding sites for one or more transcriptional activators that interact in a synergistic manner. A common view is that synergism is a manifestation of the need for many contacts between activators and the general transcription machinery that a single activator presumably cannot fulfill. In this model, various combinations of protein-protein interactions control the level of gene expression. However, we show here that under physiological conditions, a single binding site and presumably GAL4 can activate transcription to the maximum possible level in vivo. Synergistic effects in this natural system are shown to be consistent with cooperative DNA binding. These results point to DNA occupancy as the major element in fine tuning gene expression in the galactose regulon.
Managing Intercultural Teams: the Eorganization Exercise

In today's global environment, intercultural teams may become the most effective teams in an organization when their diversity is managed as an asset. However, because of miscommunication and confl...