cssi/SciSciGPT-SciSciNet huggingface dataset:
Reductive dechlorination of trichloroethylene by the CO-reduced CO dehydrogenase enzyme complex from Methanosarcina thermophila.

Trichloroethylene (TCE) was reductively dechlorinated to cis-dichloroethylene, trans-dichloroethylene, 1,1-dichloroethylene, vinyl chloride, and ethylene by the CO-reduced CO dehydrogenase enzyme complex from Methanosarcina thermophila; the apparent Km and Vmax values were 1.7 ± 0.3 mM TCE and 26.2 ± 1.7 mol TCE dechlorinated/min/mmol factor III. Factor III also catalysed the dechlorination of TCE when in the presence of titanium(III) citrate; the apparent Km and Vmax values were 1.2 ± 0.3 mM TCE and 34.9 ± 3.6 mol TCE dechlorinated/min/mmol factor III. The enzyme complex was resolved into the two-subunit nickel/iron-sulfur (Ni/Fe-S) component and the two-subunit factor III-containing corrinoid/iron-sulfur (Co/Fe-S) component. The Ni/Fe-S component was unable to dechlorinate TCE in the presence of CO; however, reconstitution with the Co/Fe-S component yielded the same dichlorinated products as with the CO dehydrogenase enzyme complex.
Threshold Characteristics of Quantum Dot Rolled-Up Microtube Lasers

We have investigated the threshold behavior of GaAs-based InAs self-organized quantum dot microtube lasers. The laser heterostructures were grown by molecular beam epitaxy and the devices were fabricated by standard optical lithography and etching techniques. Measurements have been made on microtube lasers of diameters 6, 9, and 12 . The spectral characteristics were measured by micro-photoluminescence and the data have been analyzed by considering the confinement and mode characteristics of the microtube. The threshold condition was derived after considering radiation, bending, and substrate losses associated with the devices. The threshold modal gain and excitation power are found to depend inversely on the microtube diameter.
Synthesis and Self-Assembly of RGD-functionalized PEO-PB Amphiphiles

Amphiphilic block copolymer self-assembly provides a versatile means to prepare nanoscale micelles in solution. The utilization of these structures as targeted drug delivery vehicles has motivated efforts to prepare bioactive ligand-functionalized polymer micelles. The impact of ligand conjugation on micelle morphology was examined through use of well-characterized poly(ethylene oxide)-b-poly(butadiene) (OB) block copolymers functionalized to varying extents with a biologically relevant RGD-containing peptide sequence. Micelle morphology and dilute solution behavior of RGD-functionalized OB (RGD-OB) copolymers were examined using cryogenic transmission electron microscopy (cryo-TEM) and dynamic mechanical analysis. The direct dispersion of RGD-OB copolymers into deionized water yielded a variety of structures; the observed morphologies deviated from the canonical series predicted by the overall change in amphiphile composition due to peptide conjugation. RGD functionalized spherical micelles, cylindrical micelle networks, and annular multilayer vesicles were prepared. The morphological behavior was attributed to interactions between peptide moieties conjugated to the termini of coronal chains and has implications in the design of targeting micelles for drug delivery applications.
Histone H1° expression in the developing cat retina

Histone H1(o) is a subtype of the non-core H1 histones located in the linker region of DNA between nucleosome cores and postulated to be involved in the regulation of gene expression. Studies in both the mouse retina and rat brain have correlated the terminal differentiation of cell types in these tissues to the expression of H1(o)a The expression of H1(o) in mouse retina occurs after light exposure suggesting that light may trigger the expression of H1(o). The aims of the present research were to: (1) describe the relationship of the appearance of H1(o) protein immunoreactivity to the formation of cell types and layers in the cat retina; and (2) determine whether H1(o) may be dependent on exposure to light or on other postnatal developmental events. We find the nuclei of ganglion, amacrine, and prospective bipolar cells contain H1(o) immunoreactivity before birth, prior to the terminal differentiation of these cells. In the cat retina, expression of H1(o) occurs prior to light exposure. These results show that the expression of H1 degrees protein is not required for the terminal differentiation of retinal cell types in the cat. Additionally, we find no requirement for light exposure prior to H1(o) expression. These findings are at variance with the findings in the mouse retina and are inconsistent with any cross species requirement for the expression of this histone in the terminal differentiation of cell types in the retina.
ACADEMIC ELITE IN ACCOUNTING: LINKAGES AMONG TOP-RANKED GRADUATE PROGRAMS '

The 10 top-ranked graduate programs in accounting, based on a national survey of deans and top administrators, were linked to one another by hiring in the programs one another's graduates. Almost one-half (45.9%) of the faculty members in these 10 programs (N = 172) had graduated from one of these 10 programs. It is suggested that this linkage helps these programs to maintain and enhance their prestige.
A re-examination of concepts in magnetic metals: The ‘nearly antiferromagnetic Fermi liquid’

Abstract Attempts to draw parallels between the ferromagnetic spin fluctuations of nearly ferromagnetic Fermi liquids, and the new concept of antiferromagnetic spin fluctuations in ‘nearly antiferromagnetic’ Fermi liquids are examined. It is argued that exchange interactions in Fermi liquids are normally purely ferromagnetic and that antiferromagnetic exchange and antiferromagnetic fluctuations arise from the breakdown of the Fermi-liquid theory as in the Mott insulator. Spin-density waves are a distinct phenomenon caused by umklapp effects, unrelated to local antiferromagnetic exchange interactions, and lead only to minor fluctuation effects. Experimental evidence is cited in favour of this dichotomy between two different causes for antiferromagnetism.
A Time Analysis of the Compositional Processes Used by Children Ages 7 to 11

The purpose of this study was to examine the amount of time that children of different ages, sexes, and proficiency levels spent on various compositional processes while creating a melody. The author gave 60 children (ages 7, 9, and 11) 10 minutes to compose a song on an electronic keyboard and asked each child to play his or her song and repeat it. Analysis of the 10-minute compositional periods indicated the amount of exploration, development, repetition, and silence subjects used while composing. No significant differences were found in performance between the sexes. Subjects who demonstrated proficiency in replicating their songs differed significantly in the use of repetition and exploration from those subjects who did not. Results suggest that (a) improvisation is a more appropriate creative activity than composition for 7-year-olds; (b) repetition is a necessary process in composing replicable songs; and (c) 9- and 11-year-olds are capable of using exploration, development, and repetition in a mann...
D-Ribulose-1,5-bisphosphate carboxylase/oxygenase from chemolithotrophically grown Rhizobium japonicum

Abstract Ribulose-1,5-bisphosphate carboxylase/oxygenase has been purified from chemolithotrophically grown Rhizobium japonicum SR and ribulose-5-phosphate kinase activity has also been detected in extracts of such cells. Electrophoretically homogeneous ribulosebisphosphate carboxylase/oxygenase purified in the presence of PMSF showed two types of large subunits of 55 000 and 53 000 daltons and small subunits of 14 200 daltons. The heterogeneity of large subunits was not observed when the enzyme was prepared in the presence of PMSF and DIFP. Ribulose-1,5-bisphosphate carboxylase from R. japonicum was inhibited by antibodies to this enzyme and a single precipitin band from the antibody-enzyme interaction was observed on double diffusion plates. Antibodies to R. japonicum enzyme did not cross-react on immunodiffusion plates with the ribulosebisphosphate carboxylase/oxygenases from wheat, spinach, soybean and tobacco.
Design and optimization of surface plasmon resonance based biosensor for the detection of E.coli

Finite element analysis based on the vector H-field formulation and incorporating the perturbation technique is used to optimize a surface plasmon resonance based fiber optic sensor for the detection of E coli.
Hippocampal neurons exhibit both persistent Ca2+ influx and impairment of Ca2+ sequestration/extrusion mechanisms following excitotoxic glutamate exposure.

Exposure of neurons to glutamate is an essential element of neuronal function, producing transient elevations in free intracellular calcium ([Ca2+]i) that are required for normal physiological processes. However, prolonged elevations in [Ca2+]i have been observed following glutamate excitotoxicity and have been implicated in the pathophysiology of delayed neuronal cell death. In the current study, we utilized indo-1 and fura-2ff Ca2+ imaging techniques to determine if glutamate-induced prolonged elevations in [Ca2+]i were due to persistent influx of extracellular Ca2+ or from impairment of neuronal Ca2+ extrusion/sequestration mechanisms. By experimentally removing Ca2+ from the extracellular solution following glutamate exposure, influx of Ca2+ into the neurons was severely attenuated. We observed that brief glutamate exposures ( 1 h). This persistent Ca2+ influx was not primarily mediated through traditionally recognized Ca2+ channels such as glutamate receptor-operated channels or voltage-gated Ca2+ channels. In addition to the persistent Ca2+ influx, longer glutamate exposures also produced a lasting disruption of Ca2+ extrusion/sequestration mechanisms, impairing the ability of the neuron to restore resting [Ca2+]i. These data suggest that glutamate-induced protracted [Ca2+]i elevations result from at least two independent, simultaneously occurring alterations in neuronal Ca2+ physiology, including a persistent Ca2+ influx and damage to Ca2+ regulation mechanisms.
Anti-human immunodeficiency virus activity and cytotoxicity of derivatized buckminsterfullerenes

Abstract Eleven new functional derivatives of C 60 have been tested for anti-HIV activity in peripheral blood mononuclear cells infected with HIV-1 LAV . Nine compounds displayed activity in the low micromolar range (EC 50 ), three of them lower than any fullerene derivative reported to date. With one exception, these compounds displayed no cytotoxicity up to 100 μM.
In situ localization of pea enation mosaic virus double-stranded ribonucleic acid.

Abstract Precursor ([ 3 H]uridine) incorporation studies in the presence or absence of actinomycin D (AMD) showed that AMD-insensitive nucleic acid synthesis occurred only in the nuclei in pea enation mosaic virus (PEMV)-infected pea plant tissues. Ferritin-labeled antibody studies showed that ds-RNA was present only in nuclei. In vitro hybridization of the nucleic acid from various infected or healthy cell fractions with [ 125 I]PEMV-ss-RNA indicated that PEMV-ds-RNA was primarily associated with nuclei-enriched fractions from infected cells. An in situ hybridization technique, which utilized autoradiography to detect the subcellular location of material which hybridized with [ 125 I]PEMV-ss-RNA, was developed. This method confirmed that PEMV-ds-RNA was localized in the nuclei of PEMV-infected tissues.
[22]Dehydropentaphyrin-(2.1.0.0.1) and [22]pentaphyrin-(2.1.0.0.1): Novel sapphyrin analogues

Abstract The synthesis of two novel sapphyrin-like expanded porphyrins, namely [22]dehydropentaphyrin-(2.1.0.0.1) ( 7 ) and [22]pentaphyrin-(2.1.0.0.1) ( 8 ) is described. Both of these new macrocycles have been characterized by NMR, UV-vis, and single crystal X-ray diffraction analysis.
Enhancing mathematical problem solving among third-grade students with schema-based instruction.

The purposes of this study were to assess the effects of schema-based instruction (SBI) in promoting mathematical problem solving and to investigate schema induction as a mechanism in the development of mathematical problem solving. Twenty-four 3rd-grade teachers, with 366 students, were assigned randomly to conditions that provided instruction on 4 types of word problems. The 3 16-week conditions were contrast, SBI, and SBI with practice in sorting word problems into schemas. Students were pre- and posttested on mathematical problem-solving tests and were posttested on schema development. Students receiving SBI, with and without sorting practice, improved more than the contrast group on problem-solving measures. Concurrently, the SBI groups' schema development exceeded that of the contrast group, and schema development explained a substantial portion of unique variance in students' posttreatment problem-solving performance. Results also suggested the need for additional research testing the contribution of practice in sorting word problems.
Porphyrin-catalyzed oxidation of trichlorophenol

Porphyrin—metal complexes are potentially useful to catalyze redox reactions, which convert toxic and biologically recalcitrant compounds to compounds that are less toxic and more amenable to biotreatment. Porphyrins, in the absence of proteins as in ligninases, peroxidases, and oxidases, are potentially more robust than enzymes and microbial cultures in the treatment of inhibitory substances.
Pulsed-field-gradient stimulated-spin-echo NMR study of anisotropic self-diffusion in smectic Ad liquid crystal CBOOA

Abstract Anisotropic self-diffusion coefficient tensor was determined in the smectic Ad (SAd) phase of a polar mesogen CBOOA. The pulsed-field-gradient stimulated-spin-echo NMR technique was applied in combination with angular displacement of a quadrupole coil, to obtain the diffusion coefficient components both parallel (D|) and perpendicular (D⊥) to the director for the sample oriented at the magic angle from the large magnetic field. It was found that D&.sfnc; >D⊥ (D|/D⊥ = 2.3–3.0), and the activation energies were similar for the two components. Nematic-like diffusion characteristics have been revealed.
A Dual Infection Pseudorabies Virus Conditional Reporter Approach to Identify Projections to Collateralized Neurons in Complex Neural Circuits

Replication and transneuronal transport of pseudorabies virus (PRV) are widely used to define the organization of neural circuits in rodent brain. Here we report a dual infection approach that highlights connections to neurons that collateralize within complex networks. The method combines Cre recombinase (Cre) expression from a PRV recombinant (PRV-267) and Cre-dependent reporter gene expression from a second infecting strain of PRV (PRV-263). PRV-267 expresses both Cre and a monomeric red fluorescent protein (mRFP) fused to viral capsid protein VP26 (VP26-mRFP) that accumulates in infected cell nuclei. PRV-263 carries a Brainbow cassette and expresses a red (dTomato) reporter that fills the cytoplasm. However, in the presence of Cre, the dTomato gene is recombined from the cassette, eliminating expression of the red reporter and liberating expression of either yellow (EYFP) or cyan (mCerulean) cytoplasmic reporters. We conducted proof-of-principle experiments using a well-characterized model in which separate injection of recombinant viruses into the left and right kidneys produces infection of neurons in the renal preautonomic network. Neurons dedicated to one kidney expressed the unique reporters characteristic of PRV-263 (cytoplasmic dTomato) or PRV-267 (nuclear VP26-mRFP). Dual infected neurons expressed VP26-mRFP and the cyan or yellow cytoplasmic reporters activated by Cre-mediated recombination of the Brainbow cassette. Differential expression of cyan or yellow reporters in neurons lacking VP26-mRFP provided a unique marker of neurons synaptically connected to dual infected neurons, a synaptic relationship that cannot be distinguished using other dual infection tracing approaches. These data demonstrate Cre-enabled conditional reporter expression in polysynaptic circuits that permits the identification of collateralized neurons and their presynaptic partners.
The effects of hypnosis and of imagery on bleeding time: a brief communication.

Abstract 2 studies are reported, one using hypnotized Ss selected on hypnotizability and one using Ss selected on imagery vividness, whose purpose is to examine whether non-patient Ss can control their bleeding in a laboratory setting. All Ss were cut on both arms with the “Surgicutt” device, an instrument that automatically makes a cut that will bleed from 2 to 10 minutes. Results suggest that Ss, who are instructed to reduce the bleeding time in one arm and to let the other arm bleed normally, are not able to control bleeding time.
Three remarks on “mixed diamond goods and anomalies in consumer theory: upward-sloping compensated demand curves with unchanged diamondness”

Abstract This paper reexamines Ng’s demonstration that “mixed diamond” goods (desired both as direct sources of satisfaction and for their values) can have upward-sloping compensated demand curves. I show that an upward-sloping compensated demand curve requires a large negative cross price elasticity between the mixed diamond good and the other good in the utility function. I also discuss ordinal conditions on the second-order partial derivatives of the utility function under which the mixed diamond good has a downward-sloping demand curve and decompose the compensated price effect into an income effect, a cross price effect and an own price effect.
Nitrogen budgets in flooded soils used for rice production

The flooded soil-rice plant ecosystem is extremely complex and final N budgets are the products of many N transformations modified by physical, chemical and biological agents, to a large extent controlled by 02 fluxes, but interacting with each other over time. Topics reviewed include mineralization-immobilization, nitrification-denitrification, NH 4 + fixation, NH3 volatilization, leaching and run-off lossess. Nitrogen budgets constructed for water sown rice using temperate climate data clearly show that the major mechanisms by which fertilizer N is removed is crop absorption, nitrification-dentrification and NH3 volatilization. Proper fertilizer management can reduce losses and desirably increase fertilizer use efficiency. Nitrogen budgets have proven useful in describing gains and losses from the various N transformation processes, all of which are environment and management dependent.
Circumesophageal connective control of the common inhibitory motorneuron in the crab, Carcinus maenas

Abstract 1. 1. The responses of the excitatory, specific inhibitor and common inhibitor motorneurons which innervate the opener muscle in the thoracic walking legs of Carcinus maenas were recorded in response to stimulation of isolated circumesophageal fiber bundles. 2. 2. Fiber bundles located in the medial and dorsal quadrants of the connective were observed to excite all three motor neurons. The threshold stimulus voltages required to evoke common inhibitor discharge were always several volts above that sufficient to elicit excitor and specific inhibitor discharge. 3. 3. The functional role of the common inhibitor in crabs is unknown. While the distribution of the common inhibitor to the tonic muscle fibers suggests that it has a role in locomotion, recordings from intact crabs suggest that the common inhibitor is silent during locomotion.
Spongy chalcogels of non-platinum metals act as effective hydrodesulfurization catalysts

Aerogels are low-density porous materials, made mostly of air, for which hundreds of applications have been found in recent years. Inorganic oxide-based aerogels have been known for a long time, carbon aerogels were discovered in the early 1990s and sulfur- and selenium-based aerogels (chalcogels) are the most recent additions to this family. Here we present new aerogels made of Co(Ni)–Mo(W)–S networks with extremely large surface areas and porosity. These systems are formed by the coordinative reactions of (MoS4)2− and (WS4)2− with Co2+ and Ni2+ salts in non-aqueous solvents. We show that these low-density sponge-like networks can absorb conjugated organic molecules and mercury ions, and preferentially adsorb CO2 over H2, which illustrates their high potential as gas-separation media. The chalcogels are shown to be twice as active as the conventional sulfided Co–Mo/Al2O3 catalyst for the hydrodesulfurization of thiophene. Aerogels made from metal–sulfur networks show high absorption of conjugated organic molecules and mercury ions and can easily separate H2 from CO2. Compared with the conventional sulfided Co-Mo/Al2O3 catalyst, these spongy, random porous networks are twice as active towards the hydrodesulfurization of thiophene.
Update on the high speed serializer ASIC development for ATLAS Liquid Argon calorimeter upgrade

We have been developing a serializer application-specific integrated circuit (ASIC) based on a commercial 0.25-μm silicon-on-sapphire (SOS) CMOS technology for the ATLAS liquid argon calorimeter front-end electronics upgrade. The first prototype, a 5 Gbps 16:1 serializer has been designed, fabricated, and tested in lab environment and in a 200 MeV proton beam. The test results indicate that the first prototype meets the design goals. The second prototype, a double-lane, 8 Gbps per lane serializer is under development. The post-layout simulation indicates that 8 Gbps is achievable. In this paper we present the design and the test results of the first prototype and the design and status of the second prototype.
Active and passive contributions to spatial learning

It seems intuitively obvious that active exploration of a new environment will lead to better spatial learning than will passive exposure. However, the literature on this issue is decidedly mixed—in part, because the concept itself is not well defined. We identify five potential components of active spatial learning and review the evidence regarding their role in the acquisition of landmark, route, and survey knowledge. We find that (1) idiothetic information in walking contributes to metric survey knowledge, (2) there is little evidence as yet that decision making during exploration contributes to route or survey knowledge, (3) attention to place–action associations and relevant spatial relations contributes to route and survey knowledge, although landmarks and boundaries appear to be learned without effort, (4) route and survey information are differentially encoded in subunits of working memory, and (5) there is preliminary evidence that mental manipulation of such properties facilitates spatial learning. Idiothetic information appears to be necessary to reveal the influence of attention and, possibly, decision making in survey learning, which may explain the mixed results in desktop virtual reality. Thus, there is indeed an active advantage in spatial learning, which manifests itself in the task-dependent acquisition of route and survey knowledge.
The Use of Surrogate Species in Risk Assessment: Using Life History Data to Safeguard Against False Negatives

The use of surrogate species is an important tool in predicting the effects of management decisions or the establishment of protective measures for endangered/threatened species. While relying on a handful of model species to predict the fate of scores of distantly related target species has been criticized, a quantitative measure linking life history traits and population predictions has been sorely missing. We derive here a closed-form expression aimed at determining conditions under which sublethal effects of a toxicant on surrogate species population outcomes will reliably predict outcomes of target (listed) species. We develop a critical threshold in fecundity reduction above which the surrogate species outcomes indicate positive population growth, while the listed species is driven to extinction. Thus we have established a means of determining conditions under which we are prone to making a “Type II” error in assessing ecological risk using surrogate species. Finally, we use the derived expression and life history data to compare outcomes from four different commonly used fish surrogate species (round goby, fathead minnow, smallmouth bass, cutthroat trout) and their target listed species (Chinook and Coho salmon). We illustrate that all four surrogate species fail to predict population outcomes for the listed species in cases of as little as 15% fecundity reduction due to toxicant exposure. Furthermore, surrogate species reliability is a function of toxicant level, so that some species are reliable at some levels but not at others. We discuss the implications of these findings, and outline further analyses that occur as a natural extension of the criteria developed here.
Epigenetic Alunite Pisolites Formed by Natural Gases in Western Merced County, California: ABSTRACT

Chemical and mineralogic processes related to the migration of natural gases are of importance for petroleum geology. An unusual alteration of sedimentary formations by hydrogen sulfide-bearing natural gases in western Merced County, California, has been described. The alteration created an acidic medium (with pH values ranging from 0.5 to 4.5) containing sulfur, sulfides, sulfates, and black and white discoloration. A peculiar layer of pisolitic sandstone was noted in the altered area near the boat-launching ramp on the southeastern shore of the O'Neill Reservoir. Individual pisolites 2-15 mm in diameter are present as an undulatory layer in a bed of light-gray, fluvial sandstone of the Tulare Formation, below the Pleistocene Corcoran Clay Member. X-ray diffraction of the sandstone cement yielded abundant alunite. Data collected during studies of iron sulfide concretions from the same locality yielded some information on origin of pisolites. An aluminum sulfate-bearing gel was repeatedly obtained by solution of concretions in concentrated nitric acid. Aluminum was produced by decomposition of alumosilicates with sulfuric acid derived from oxidation of sulfides cement. Alunite pisolites probably originated by decomposition of alumosilicates occurring in sandstone by reaction with sulfuric acid created by oxidation of hydrogen and/or iron sulfides in excavations. Natural gases in the area, following joints, tend to cause dome-shaped uplifts in overburden, which explains the undulatory occurrence of pisolitic layers. Their position could be controlled by a capillary uplift. End_of_Article - Last_Page 961------------
A Novel Outage Capacity Objective Function for Optimal Performance Monitoring and Predictive Fault Detection in Hybrid Free-Space Optical and RF Wireless Networks

This study develops an optimal performance monitoring metric for a hybrid free space optical and radio wireless network, the Outage Capacity Objective Function. The objective function—the dependence of hybrid channel outage capacity upon the error rate, jointly quantifies the effects of atmospheric optical impairments on the performance of the free space optical segment as well as the effect of RF channel impairments on the radio frequency segment. The objective function is developed from the basic information-theoretic capacity of the optical and radio channels using the gamma-gamma model for optical fading and Ricean statistics for the radio channel fading. A simulation is performed by using the hybrid network. The objective function is shown to provide significantly improved sensitivity to degrading performance trends and supports of proactive link failure prediction and mitigation when compared to current thresholding techniques for signal quality metrics.
Preoperative ultrasound measurements predict the feasibility of gallbladder extraction during transgastric natural orifice translumenal endoscopic surgery cholecystectomy

Extraction of a gallbladder through an endoscopic overtube during natural orifice translumenal endoscopic surgery (NOTES®) transgastric cholecystectomy avoids potential injury to the esophagus. This study examined the rate of successful gallbladder specimen extraction through an overtube and hypothesized that preoperative ultrasound findings could predict successful specimen passage. Gallbladder specimens from patients undergoing laparoscopic cholecystectomy were measured, and an attempt was made to pull the specimens through a commercially available overtube with an inner diameter of 16.7-mm. A radiologist blinded to the outcomes reviewed the available preoperative ultrasound measurements from these patients. Ultrasound dimensions including gallbladder length, width, and depth; wall thickness; common bile duct diameter; and size of the largest gallstone (LGS) were recorded. Multiple logistic regression analysis was performed to determine whether ultrasound findings and patient characteristics (age, body mass index [BMI], and sex) could predict the ability of a specimen to pass through the overtube. Of 57 patients, 44 (77%) who had preoperative ultrasounds available for electronic review were included in the final analysis. Gallstones were present in 35 (79%) of these 44 patients. Intraoperative gallbladder perforation occurred in 18 (41%) of the 44 patients, and 16 (36%) of the 44 gallbladders could be extracted through the overtube. Measurement of LGS was possible for 23 patients, and indeterminate gallstone size (IGS) was determined for 12 patients. The rate for passage of perforated versus intact gallbladders was similar (40% vs. 23%; p = 0.054). The LGS (odds ratio [OR], 1.17; 95% confidence interval [CI], 1.02–1.33; p = 0.021) and IGS (OR, 22.97; 95% CI, 1.99–265.63; p = 0.025) predicted failed passage on multivariate logistic regression analysis. The passage rate was 80% for LGS smaller than 10 mm or no stones present, 18% for LGS 10 mm or larger, and 8% for IGS (p < 0.001). A majority of cholecystectomy specimens cannot pass through an endoscopic overtube. Preoperative ultrasound findings can predict successful specimen extraction. An IGS or a gallstone 10 mm or larger should be considered a relative contraindication to transgastric NOTES cholecystectomy.
Time-dependent correlations between a pair of distinguishable particles hopping on a uniform one-dimensional chain

We derive equations for the time-dependent correlation function describing the relative motion of a pair of distinguishable particles hopping on a one-dimensional linear chain with all sites equivalent. This correlation function is directly proportional to the magnetization relaxation rate (${T}_{1}^{\ensuremath{-}1}$) in NMR experiments when the relaxation is due to the dipolar interaction between hopping spins. The equations are exact in the limit where the concentration of vacancies on the chain is small and, we believe, yield qualitatively good results for other concentrations. In the limit where the frequency $\ensuremath{\omega}$ is much less than the hopping rate we predict that the correlation function and thus ${T}_{1}^{\ensuremath{-}1}$ are proportional to ${\ensuremath{\omega}}^{\ensuremath{-}\frac{3}{4}}$. For three-dimensional systems the relaxation rate is frequency independent in this limit while crude (and incorrect) one-dimensional arguments lead to a ${\ensuremath{\omega}}^{\ensuremath{-}\frac{1}{2}}$ dependence.
An allelic series for the leptin receptor gene generated by CRE and FLP recombinase

Body weight regulation is mediated through several major signaling pathways, some of which have been delineated by positional cloning of spontaneous genetic mutations in mice. Lepr(db/db) mice are obese due to a defect in the signaling portion of the leptin receptor, which has led to extensive study of this highly conserved system over the past several years. We have created an allelic series at Lepr for the further examination of LEPR signaling phenotypes using both the FLP /frt and CRE /loxP systems. By inserting a frt-PGK-neo-frt sequence in Lepr intron 16, we have generated a conditional gene repair Lepr allele ( Lepr-neo) that elicits morbid obesity, diabetes, and infertility in homozygous mice, recapitulating the obesity syndrome of Lepr(db/db) mice. Thus, in vivo excision of the PGK-neo cassette with a FLP recombinase transgene restores the lean and fertile phenotype to Lepr(flox/flox) mice. In the same construct, we have also inserted loxP sites that flank Lepr coding exon 17, a region that encodes a JAK docking site required for STAT3 signaling. CRE-mediated excision of Lepr coding exon 17 from Lepr with a frameshift in subsequent exons results in a syndrome of obesity, diabetes, and infertility in LeprDelta17/Delta17 mice, which is indistinguishable from Lepr(neo/neo) and Lepr(db/db) mice. We conclude that suppression of Lepr gene expression by PGK-neo is phenotypically equivalent to deletion of the Lepr signaling motifs, and therefore the Lepr(neo/neo) mouse may be used to investigate conditional gene repair of Lepr signaling deficiency.
An Examination of Wind Decay, Sustained Wind Speed Forecasts, and Gust Factors for Recent Tropical Cyclones in the Mid-Atlantic Region of the United States

AbstractIn this study, several analyses were conducted that were aimed at improving sustained wind speed and gust forecasts for tropical cyclones (TCs) affecting coastal regions. An objective wind speed forecast analysis of recent TCs affecting the mid-Atlantic region was first conducted to set a benchmark for improvement. Forecasts from the National Digital Forecast Database were compared to observations and surface wind analyses in the region. The analysis suggests a general overprediction of sustained wind speeds, especially for areas affected by the strongest winds. Currently, National Weather Service Weather Forecast Offices use a software tool known as the Tropical Cyclone Forecast/Advisory (TCM) wind tool (TCMWindTool) to develop their wind forecast grids. The tool assumes linear decay in the sustained wind speeds when interpolating the National Hurricane Center 12–24-hourly TCM product to hourly grids. An analysis of postlandfall wind decay for recent TCs was conducted to evaluate this assumption....
Estimation of the two-dimensional presampled modulation transfer function of digital radiography devices using one-dimensional test objects.

Purpose: The modulation transfer function (MTF) of medical imaging devices is commonly reported in the form of orthogonal one-dimensional (1D) measurements made near the vertical and horizontal axes with a slit or edge test device. A more complete description is found by measuring the two-dimensional (2D) MTF. Some 2D test devices have been proposed, but there are some issues associated with their use: (1) they are not generally available; (2) they may require many images; (3) the results may have diminished accuracy; and (4) their implementation may be particularly cumbersome. This current work proposes the application of commonly available 1D test devices for practical and accurate estimation of the 2D presampled MTF of digital imaging systems. Methods: Theory was developed and applied to ensure adequate fine sampling of the system line spread function for 1D test devices at orientations other than approximately vertical and horizontal. Methods were also derived and tested for slit nonuniformity correction at arbitrary angle. Techniques were validated with experimental measurements at ten angles using an edge test object and three angles using a slit test device on an indirect-detection flat-panel system [GE Revolution XQ/i (GE Healthcare, Waukesha, WI)]. The 2D MTF was estimated through a simplemore » surface fit with interpolation based on Delaunay triangulation of the 1D edge-based MTF measurements. Validation by synthesis was also performed with simulated images from a hypothetical direct-detection flat-panel device. Results: The 2D MTF derived from physical measurements yielded an average relative precision error of 0.26% for frequencies below the cutoff (2.5 mm{sup -1}) and approximate circular symmetry at frequencies below 4 mm{sup -1}. While slit analysis generally agreed with the results of edge analysis, the two showed subtle differences at frequencies above 4 mm{sup -1}. Slit measurement near 45 Degree-Sign revealed radial asymmetry in the MTF resulting from the square pixel aperture (0.2 mm Multiplication-Sign 0.2 mm), a characteristic which was not necessarily appreciated with the orthogonal 1D MTF measurements. In simulation experiments, both slit- and edge-based measurements resolved the radial asymmetries in the 2D MTF. The average absolute relative accuracy error in the 2D MTF between the DC and cutoff (2.5 mm{sup -1}) frequencies was 0.13% with average relative precision error of 0.11%. Other simulation results were similar to those derived from physical data. Conclusions: Overall, the general availability, acceptance, accuracy, and ease of implementation of 1D test devices for MTF assessment make this a valuable technique for 2D MTF estimation.« less
Pulsed laser deposition of mesoporous niobium oxide thin films and application as chemical sensors

Abstract The pulsed laser deposition (PLD) of a mesoporous niobium oxide, Nb-TMS1, and post-hydrothermal treatment result in mesoporous thin films (90 nm–3 μm thick) having what appears to be a three-dimensional disordered hexagonal or `wormhole' structure. These films were characterized by FT-IR spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The mesoporous Nb-TMS1 thin films were employed as the dielectric phase in capacitive-type chemical sensors. These sensors produce a capacitance change upon the reversible absorption of volatile compounds into the molecular sieve pores. The molecular sieve based sensors were exposed to a variety of analytes, including N 2 , CO 2 , H 2 O, NH 3 , methanol and acetone. The mesoporous niobium oxide based sensors were found to be particularly good humidity sensors, exhibiting capacitance changes at least 10 times greater than that for N 2 , ammonia, methanol and acetone. The Nb-TMS1 based sensors also showed responses to H 2 O that were 1000 times greater than for dense Nb 2 O 5 based sensors prepared by PLD.
The shape relaxation of liquid droplets in solids

Abstract The shape relaxation of artificially extended brine droplets in solid KCl was followed through the entire relaxation process with an optical transmission microscope. Irreversible processes associated with the transfer of salt atoms between the solid and liquid at the solid-liquid interfaces of the droplet significantly slowed the relaxation process and prevented the droplets from ever attaining their equilibrium shapes of minimum surface energy. This departure from shape equilibrium increased with droplet size in a manner predicted by a model extending the equilibrium work of Gibbs to the non-equilibrium situation. By comparing the droplet relaxation rate with this model, the brine-KCl interface energy was estimated to be 12 ergs/cm2 which agrees well with the KCl-brine interface energy independently determined by measuring the contact angles of brine droplets on grain boundaries of KCl.
Circulating proinsulin-like component in man: increased proportion in hypoinsulinemic states.

The proportion of total plasma immunoreactive insulin comprising the proinsulin-like component was determined in 5 diabetic subjects manifesting fasting hyperglycemia, severe glucose intolerance, and insulinopenia, and also in one insulinopenic patient both before and after removal of a phaeochromocytoma. The proinsulin-like component comprised a mean of 37% (range 30–50%) of the total immunoreactive insulin in the basal state, 27% (range 20–32%) at 15 min, and 32% (range 23–50%) 120 min after 100g of oral glucose. These values are significantly higher than in normal subjects or patients with hyperinsulinemic responses (excepting patients with insulinoma). Our studies suggest that diseases that affect the B-cell's ability to store insulin or prevent the secretory granule of the B-cell from undergoing full maturation will be associated with an increased secretion from immature granules, that contain a higher percentage of proinsulin-like components. The proportion of the total immunoreactive insulin comprising the proinsulin-like component is, therefore, a reflection of the integrity of the B-cell granule.
Suppression of counterregulatory hormone response to hypoglycemia by insulin per se.

ABSTRACT Although assessment of counterregulatory hormone responses to hypoglycemia relies upon insulin to lower the glucose level, it is not known if the exogenous insulin dose used itself influences the magnitude of the hormone response. To assess this, 12 normal subjects randomly received 2 hypoglycemic clamp studies in which the only variable was the insulin dose (0.6 or 5.0 mU/kg-min). Despite 10-fold differences in circulating insulin (265±29 vs 2576±222 pmol/L respectively), the hypoglycemic stimulus did not vary. Glucose levels fell over one hour, and then were maintained for two hours at the same hypoglycemic plateau (approximately 3.1 mmol/L for each study) by a variable glucose infusion. Although basal counterregulatory hormone levels in low and high dose studies were indistinguishable, during hypoglycemia the response of epinephrine, growth hormone, and glucagon was significantly suppressed when the degree of hyperinsulinemia was increased. We conclude that raising the magnitude of hyperinsuli...
On the Diversity of Diversity: Tidy Logic, Messier Realities

The article is a response to the article “Making the Difference: Applying a Logic of Diversity,” by Scott Page in this issue of the journal. The authors focus their critique on the simplicity of Page's arguments and frameworks, contending that the reality of the workplace is not so simply organized. The authors also critique Page for a too narrow conceptualization of diversity, limiting it to knowledge, heuristics, and perspectives. The authors also cite Page's egalitarian group dynamics as unrealistic.
Low-voltage elctrostatic actuation of droplet on thin superhydrophobic nanoturf

This paper reports an electrostatic actuation of droplets on a NanoTurf surface. By employing the nanostructured layer instead of a flat and smooth dielectric, both a large driving force and low friction are achieved, presenting a droplet operation at a lower driving voltage compared with general electrowetting-on-dielectric (EWOD) configurations. The dielectric NanoTurf layer is formed on electrodes by using laser interference lithography. With a contact angle of ~170deg and its hysteresis of ~5deg on syperhydrophobic NanoTurf, water droplets are actuated at ~24 V, much lower than general EWOD.
Pediatric trauma recidivism in an urban cohort

BACKGROUND: Recidivism is a well-known problem in adult trauma patients. Trauma recidivists are a population that warrants further intervention to prevent future trauma. Among pediatric patients, the recidivism rate, demographics, mechanism, and mortality are unknown. We hypothesized that specific groups of pediatric trauma recidivists could be identified for targeted prevention efforts. METHODS: All pediatric trauma patients admitted to a level 1 pediatric trauma center in an urban county hospital between 1991 and 2010 were reviewed. Age, sex, Glasgow Coma Scale, injury location, injury cause, disposition, length of stay, and mortality were collected and compared between nonrecidivist and recidivist cohorts. RESULTS: The recidivism rate among patients aged 0-19 y was 1.5% compared with 0.9% in those aged 0-16 y. Recidivists were more likely males (P Language: en
FIRMA: a method for detection of alternative splicing from exon array data

Motivation: Analyses of EST data show that alternative splicing is much more widespread than once thought. The advent of exon and tiling microarrays means that researchers now have the capacity to experimentally measure alternative splicing on a genome wide level. New methods are needed to analyze the data from these arrays. Results: We present a method, finding isoforms using robust multichip analysis (FIRMA), for detecting differential alternative splicing in exon array data. FIRMA has been developed for Affymetrix exon arrays, but could in principle be extended to other exon arrays, tiling arrays or splice junction arrays. We have evaluated the method using simulated data, and have also applied it to two datasets: a panel of 11 human tissues and a set of 10 pairs of matched normal and tumor colon tissue. FIRMA is able to detect exons in several genes confirmed by reverse transcriptase PCR. Availability: R code implementing our methods is contributed to the package aroma.affymetrix. Contact: epurdom/at/stat.berkeley.edu Supplementary information: Supplementary data are available at Bioinformatics online.
Structural analysis of the cerebral cortex using blind source separation

Blind Source Separation (BSS) methods have become ubiquitous, but their performance varies greatly depending on how well their assumptions are satisfied by the data. Cortical thickness and sulcal folding patterns are ideal datasets for BSS analysis because there is limited prior knowledge on how they are affected by brain development and pathologies of the central nervous system. However, to date there are no studies exploring these datasets with BSS methods. We propose a novel spatial BSS method based on the Second Order Blind Identification (SOBI) method, but tailored for data on the cerebral cortex. Simulations show our method outperforms the regular SOBI and popular FastICA methods. Experimental data reveal underlying patterns in cortical maps of curvature variance.
A hands-on Bioelectric Potentials course for Electrical Engineering majors

We describe a new course in Bioelectric Potentials, offered to seniors in a 4-year Electrical Engineering program, that integrates bioelectric mechanisms, numerical methods and simulation, hardware design, and technical writing. The course focused on mechanisms governing the generation of bioelectrical signals together with measurement and analysis techniques in muscle and nerve electrophysiology. Topics covered included the Nernst potential; development of action potentials; impulse propagation and nerve conduction; membrane biophysics; excitation-contraction coupling; and the development and management of cardiac arrhythmias. The course incorporated quantitative modeling and simulation learning exercises for data analysis and outcome prediction. Students were exposed to numerical methods for curve fitting, integration, differentiation, and solving ordinary differential equations. The course also incorporated hands-on activities including the building of an ECG amplifier and QRS detector circuit, and the measurement of their own EMG, ECG, and EEG signals using the ADInstruments PTB 32 Teaching System. Technical communication skills, both oral and written, were reinforced through three project reports and in-class presentations of pertinent journal articles. Assessment of student learning and achievement of course objectives will be presented.
Bayesian approach to average power calculations for binary regression models with misclassified outcomes

We develop a simulation-based procedure for determining the required sample size in binomial regression risk assessment studies when response data are subject to misclassification. A Bayesian average power criterion is used to determine a sample size that provides high probability, averaged over the distribution of potential future data sets, of correctly establishing the direction of association between predictor variables and the probability of event occurrence. The method is broadly applicable to any parametric binomial regression model including, but not limited to, the popular logistic, probit, and complementary log-log models. We detail a common medical scenario wherein ascertainment of true disease status is impractical or otherwise impeded, and in its place the outcome of a single binary diagnostic test is used as a surrogate. These methods are then extended to the two diagnostic test setting. We illustrate the method with categorical covariates using one example that involves screening for human papillomavirus. This example coupled with results from simulated data highlights the utility of our Bayesian sample size procedure with error prone measurements.