cssi/SciSciGPT-SciSciNet huggingface dataset:
Identification of the Single Channels that Underlie the N-Type and L-Type Calcium Currents in Bullfrog Sympathetic Neurons

Most of the whole-cell calcium current of frog sympathetic neurons is an N-type current, blocked by ω-conotoxin GVIA (ωCGVIA). Thus, these cells should be an excellent system to study the properties of single N-type channels. However, a channel that is active near −10 mV in isotonic Ba2+, originally identified as “N-type,” corresponds more closely to a ωCGVIA-resistant component of the whole-cell current observed in 100 mm Ba2+. That conclusion would imply that the true single-channel correlate of the macroscopic N-current remains to be identified in frog sympathetic neurons. I report here recordings from cell-attached patches of a calcium channel that activates in the appropriate voltage range (>0 mV, in isotonic Ba2+) and is blocked by ωCGVIA. This channel has a slope conductance of 20 pS (range, 17–25 pS) and a single-channel current of −1.3 pA at 0 mV. Other channels active in the same voltage range (24 pS, −1.3 pA at 0 mV) were identified as L-type channels because they exhibited long openings after repolarization in the presence of 1 μm Bay K 8644 and were resistant to ωCGVIA. A third channel type (13–19 pS) was distinguished by current amplitude (−0.6 pA at 0 mV) and strong inactivation at −40 mV. The similarity in slope conductance among these channels demonstrates that distinguishing them requires the consideration of additional properties. The ωCGVIA-sensitive channel can be identified as an N-type calcium channel.
Potentiation of acetylcholine receptors by divalent cations.

Divalent cations promote activation of several nicotinic acetylcholine receptor (AChR) subtypes, presumably by lowering the energetic barrier between open and closed conformations. In wild-type α7 AChRs, binding of calcium to a particular part of the extracellular domain is required for potentiating activation. McLaughlin et al. (p. 16) tested the hypothesis that movements involved in agonist activation and calcium modulation involve a nearby β sheet by linking strands within this sheet through disulfide bonds formed by replacing adjacent amino acids with cysteines to alter its mobility. These studies are helping to reveal how movements initiated by agonist binding to ACh binding sites are propagated through the extracellular domain of AChRs to regulate opening of the cation channel through the membrane.
Metabolic behaviour of 137Cs-137mBa in the lactating goat.

SummaryInvestigations on the metabolism of 137Cs in the lactating goat demonstrated that: (a) the biological half-time for removal of 137Cs from the body was about 2–3 days, (b) at steady state, about 7 per cent of the daily dose of ingested 137Cs was secreted daily in milk, about 40 per cent in the urine and about 40 per cent in the faeces, (c) the 137Cs/K ratio in milk was 1·4 based on a dietary 137Cs/K ratio of unity, (d) the mammary gland did not differentiate between 137Cs and K, (e) the organ of highest concentration was kidney, with values 1·5 times that of muscle and other soft tissues, (f) the 137mBa daughter metabolically dissociated from its 137Cs parent in vivo so that the gamma activity of the whole blood of the living animal was 5·5 times that as usually determined. These and other findings are discussed and reference made to differences in 137Cs metabolism between ruminants and non-ruminants.
Making digital leaf collages with blow painting

We present a novel play interface called Blow Painting that enables people to create leaf collage paintings on a digital canvas by blowing at a toy windmill. The toy windmill detects the blowing action and direction with its embedded microphone and rotation sensor. Four kinds of leaf "stencils" (Red Maple, Sugar Maple, Hickory and White Oak) are embedded in the transparent RFID sheets to be placed under the windmill for the play interaction. We describe the motivation, system components, an informal pilot test, and discuss directions for future work.
Surprises in fault tolerance and cluster dynamics for quantum computing

We explore basic necessary protocols to achieve fault tolerance for quantum computation in the cluster state and circuit models. For the cluster state model we simulate the implementation of an arbitrary rotation via only measurement on a decohered cluster state. Fidelity is used to quantify the accuracy of the initial cluster state and a gate fidelity for the arbitrary rotation is determined. In the circuit model we compare the accuracy of two methods that can be used to construct a logical zero state appropriate for the [7, 1, 3] Steane quantum error correction code in a non-equiprobable Pauli operator error environment: a fault tolerant method done by applying error correction on seven qubits all in the state zero, and a non-fault tolerant method done by implementing the encoding gate sequence. We find that the latter construction method, in spite of its lack of "fault tolerance," outputs a seven qubit state with a higher fidelity than the first (fault tolerant) method. However, the fidelity of the single qubit of stored information exhibits almost equivalent values between the two construction methods.
Dissipative tunneling with periodic polychromatic driving: Exact results and tractable approximations

Abstract We investigate the long-time dynamics in dissipative two-level-systems (TLS) when driven by — monochromatic or pulse-shaped — periodic fields. The environmental influence is investigated within the noninteracting-blip approximation (NIBA), while no restrictions are assumed on the driving force. With the focus being on electron-transfer (ET) reactions in condensed media, we consider a continuous Ohmic spectrum for the bath modes. The asymptotic dynamics exhibits always the periodicity of the external force. The induced oscillations show a smooth periodic behavior which becomes richer, if, for example, multiphoton resonances occur. For monochromatic driving, the oscillatory multiresonance pattern becomes gradually smoothed out when the temperature, and/or the Ohmic strength are sufficiently high. It may persist, however, for pulse-shaped driving. Exact NIBA analytical and/or numerical solutions, for both the Ohmic transfer rate and for the driven dynamics, are used to determine the validity range of the short-time approximation for the bath correlation functions. The latter is frequently employed to investigate the ET dynamics. Our analysis shows that the short-time approximation may give qualitative incorrect results at low temperatures.
Hinges-free and hinges-locked modes of a deformable multibody Space Station - A continuum analysis

An analytical theory of two classes of vehicle modes for a multibody, deformable space station is presented: 1) hinges-free modes and 2) hinges-locked modes. Both modes are defined for the space station completely free in space; the former modes refer to free hinges, and the latter to locked hinges. Associated eigenvalue problems and orthogonality properties are developed and used to arrive at concise linear motion equations. The conciseness transpires because, with these vehicle modes, the translational and rotational deformations of an inboard body at a hinge have a simple modal expansion. Modal momental coefficients associated with both classes of modes are formulated. They play a pivotal role in discretization of partial differential equations governing the dynamics. The analysis is general: elastic deformation is three dimensional, structures have arbitrary geometry and obey Hooke's law of elasticity, and hinges are universal joints. The modal coefficients and dynamics of the space station are illustrated, and the pitfalls in using hinges-locked vehicle modes to predict hinges-free response are identified. A continuum formulation of dynamics of the space station with a mobile manipulator is also furnished.
Comparison of chlorinated hydrocarbon pesticides in maternal blood and placental tissues.

Abstract Fifty-three paired placental and maternal blood specimens were collected from women in a general population and analyzed for the chlorinated hydrocarbon pesticides. All specimens were analyzed by electron gas liquid chromatography. Chlorinated hydrocarbons, previously reported in human adipose and blood specimens (DDT, DDE, DDD, dieldrin, aldrin, BHC, lindane, and heptachlor epoxide), were detected in the placental and maternal blood specimens. DDE, DDT and lindane were detected more frequently. No marked differences were observed among residence, age, or race because the population group sampled was fairly homogeneous with similar environmental sources of exposure to the chlorinated hydrocarbon pesticides. To our knowledge, this is the first reported comparison of the chlorinated hydrocarbon levels detected in placental and maternal blood specimens, as well as the detection of aldrin and heptachlor in placental and blood specimens collected from women in a general population, i.e., without occupational or accidental exposure to these pesticides.
Zinc ion conducting polymer electrolytes based on oligomeric polyether/PVDF-HFP blends

Here we report novel zinc ion conducting polymer electrolytes based on oligomeric polyether/PVDF-HFP blends with or without the incorporation of a small amount of organic carbonates. Their thermal properties, ionic conductivity and electrochemical properties are characterized and the effect of different Zn salts and incorporation of a small amount of organic carbonates are investigated. These polymer electrolyte membranes exhibit essentially no or very low volatility, high thermal stability, high ionic conductivity, wide electrochemical stability window, acceptable interfacial resistance with zinc, and the capability for reversible Zn plating/stripping. Particularly promising are electrolyte systems based on the combination of low lattice energy zinc imide salt and a special co-solvent of oligomeric poly(ethylene glycol) dimethyl ether (PEGDME) mixed with a small amount of ethylene carbonate (EC), dimensionally stabilized with PVDF-HFP. Such novel polymer electrolyte membranes could lead to the development of new kinds of electrochemical energy storage devices based on zinc electrochemistry, including solid-state, thin-film rechargeable zinc/air cells envisaged.
Characterization and uniqueness of distinguished self-adjoint extensions of Dirac operators

Distinguished self-adjoint extensions of Dirac operators are characterized by Nenciu and constructed by means of cut-off potentials by Wust. In this paper it is shown that the existence and a more explicit characterization of Nenciu's self-adjoint extensions can be obtained as a consequence from results of the cut-off method, that these extensions are the same as the extensions constructed with cut-off potentials and that they are unique in some sense.
Immunological thought in the mainstream of cancer research: Past divorce, recent remarriage and elective affinities of the future

Immunological thought is exerting a growing effect in cancer research, correcting a divorce that occurred in the mainstream of the field decades ago just as cancer genetics began to emerge as a dominant movement. Today, with a general consensus on the significance of epigenetics, the inflammatory cancer microenvironment and the immune response in determining cancer pathophysiology, a new synthesis of thought is being spurred by a remarriage with cancer immunology, with great implications for the future of the field. This perspective offers a view on how this synthesis is impacting both the understanding and treatment of cancer using adjuvant immunomodulatory modalities in the context of surgical, radiotherapeutic and chemotherapeutic interventions which are present standards of care. With the revolutions in immunochemotherapy and immunoradiotherapy coming this decade, the next great challenge faced by the field will be how to identify simple, cost effective and broadly applicable solutions that do not rely deeply on personalized characters, in an effort to minimize the daunting complexity and costs of a problem that challenges not only physicians and patients but also health care systems and insurers caring for aging populations in the developed world.
Unusual mantle Poisson's ratio, subduction, and crustal structure in central Alaska

[1] Subduction zones alter the upper plate in a variety of ways, including metasomatism via slab-derived fluids and accretion of exotic terranes. These processes should produce distinctive seismic signatures, as seismic velocities are sensitive to compositional variations. A new method is developed to estimates depths to interfaces and Poisson's ratio (Vp/Vs ratio) for dipping layered structures, by stacking teleseismic receiver functions. It also estimates crustal Vp/Vs and thickness. Using this method, we analyze a broadband data set from the central Alaska subduction zone, to seek evidence for mantle wedge composition. Crustal thickness varies from 27 to 45 km, and crustal Vp/Vs indicates an intermediate to mafic composition, expected for these accreted island arc terranes. Inversions for mantle structure confirm the presence of a 15–20 km thick low-velocity zone atop of the downgoing plate to 130 km depth, perhaps subducted crust of an exotic terrane. Vp/Vs in the mantle wedge allows for 15 ± 15% serpentinization where the slab is <80 km deep and the wedge is cold. Where the slab is deeper, Vp/Vs for the mantle wedge is unusually low, <1.7. This value is lower than predicted for any common mantle mineral and may indicate significant quantities of quartz, provided that past physical properties measurements are not grossly in error. These results suggest that the mantle wedge in subduction zones can occasionally differ substantially in bulk composition from normal subcrustal mantle, perhaps because collisions of exotic terranes cause tectonic mixing of crustal material into the mantle.
IMPROVING THE EFFICIENCY OF CHEMICAL SANITIZERS USED IN BULK STORAGE TANKS

The cleaning-sanitizer sequence which is now being successfully used on aseptic bulk tanks for storage of acid products was evaluated for future use with low acid foods. The AOAC Sporicidal Test utilizing unglazed porcelain penicylinders and cylinders coated with the bulk tanks lining material was used to appraise the cleaning and sanitizing sequence. Various modifications of the original standard cleaning sequence were also tested. Spores dried on the two carriers displayed dramatically different destructive rates. Further investigation is considered necessary to completely evaluate various pretreatments for low acid food storage.
Market Driven Winners.

Who will prosper in today’s environment of rapid and unpredictable change? Some would say that newcomers will have an advantage because they have no history to overcome or earnings to protect. There are many examples of upstarts who have used a superior market orientation to gain significant advantage over incumbents with far greater resources. It is not size or history that counts, but a superior ability to understand, attract and keep their valuable customers. In other words, the winning firms – whatever other advantage they may have – will also be market driven. Becoming market driven is not something that is done quickly or easily. It cannot be delegated to the marketing department for it requires the willing involvement of all functions. Many firms will take up the market-driven banner but will not succeed either because of a shortage of knowledge or a lack of determination. It is a far-reaching and fundamental change for many organizations, requiring them to abandon the very traditions that contributed to their past success.
Incidence of Iatrogenic Ureteral Injury After Laparoscopic Colectomy

Objective To compare the incidence of iatrogenic ureteral injury between laparoscopic and open colectomies at a single institution. Design From June 1, 2005, through July 31, 2010, patients were identified from a prospectively maintained database and hospital records were retrospectively reviewed. Setting Mount Sinai Medical Center. Patients Fourteen patients who underwent colectomy complicated by a ureteral injury. Main outcome measures A significant increase in ureteral injuries occurred after laparoscopic vs open procedures (0.66% vs 0.15%, P = .007). Results A total of 5729 colectomies were performed during the study period. Fourteen ureteral injuries occurred, resulting in a 0.244% incidence of iatrogenic ureteral injury. Patient demographics demonstrated that 9 injuries (64%) occurred in females and 7 patients (50%) had undergone prior abdominal operations. Operative indications were inflammatory bowel disease (n = 7), diverticulitis (n = 2), and malignant neoplasm (n = 4). Thirteen operations (87%) in this study were elective colectomies, and 7 patients (50%) underwent laparoscopic procedures, with 2 open conversions. Of the 5729 colectomies, 4669 were open and 1060 laparoscopic. Regarding ureteral injuries, no difference was observed in intraoperative identification of ureteral injury in patients who underwent preoperative ureteral stent placement (n = 4) vs those who did not (50% [2 of 4] vs 50% [5 of 10]). Conclusions A significant increase was found in the incidence of iatrogenic ureteral injuries with laparoscopy compared with open colectomies. Preoperative stent placement did not ensure intraoperative identification of injury. Female sex and increased operative blood loss appear to predispose patients to injury.
“Adatom” sites, structure and mobility effects on the sers of cyanine

Abstract The origins of specific surface-enhanced Raman scattering (SERS) bands of 2,2′-cyanine in an electrochemical system using 488 nm excitation are discussed. Under special conditions of concentration and potential, using KI as supporting electrolyte, bands can be grouped according to their potential dependency. Experimental evidence shows that several cyanine bands are attributable to aggregated molecules. Some cyanine bands depend on the presence of different sites that can be enhanced by exposure to pulsed laser radiation; the temporal behavior of some bands indicates that different surface mobilities exist for some of the molecules.
The cation efflux transporter ZnT8 (Slc30A8) is a major autoantigen in human type 1 diabetes

Type 1 diabetes (T1D) results from progressive loss of pancreatic islet mass through autoimmunity targeted at a diverse, yet limited, series of molecules that are expressed in the pancreatic β cell. Identification of these molecular targets provides insight into the pathogenic process, diagnostic assays, and potential therapeutic agents. Autoantigen candidates were identified from microarray expression profiling of human and rodent pancreas and islet cells and screened with radioimmunoprecipitation assays using new-onset T1D and prediabetic sera. A high-ranking candidate, the zinc transporter ZnT8 (Slc30A8), was targeted by autoantibodies in 60–80% of new-onset T1D compared with <2% of controls and <3% type 2 diabetic and in up to 30% of patients with other autoimmune disorders with a T1D association. ZnT8 antibodies (ZnTA) were found in 26% of T1D subjects classified as autoantibody-negative on the basis of existing markers [glutamate decarboxylase (GADA), protein tyrosine phosphatase IA2 (IA2A), antibodies to insulin (IAA), and islet cytoplasmic autoantibodies (ICA)]. Individuals followed from birth to T1D showed ZnT8A as early as 2 years of age and increasing levels and prevalence persisting to disease onset. ZnT8A generally emerged later than GADA and IAA in prediabetes, although not in a strict order. The combined measurement of ZnT8A, GADA, IA2A, and IAA raised autoimmunity detection rates to 98% at disease onset, a level that approaches that needed to detect prediabetes in a general pediatric population. The combination of bioinformatics and molecular engineering used here will potentially generate other diabetes autoimmunity markers and is also broadly applicable to other autoimmune disorders.
Effect of transforming growth factor-beta 1 on myocardial stunning in the intact dog

Previous studies have demonstrated that transforming growth factor-beta (TGF-beta) can accelerate wound healing, inhibit free radical formation and limit myocardial ischemia/reperfusion injury in a variety of experimental models. However, it is unknown whether exogenous TGF-beta 1 can attenuate the prolonged contractile dysfunction that is observed after a brief, reversible ischemic insult (myocardial stunning). Thus, open-chest dogs undergoing a 15-min left anterior descending coronary artery occlusion and 4 h of reperfusion were given TGF-beta 1 as an intravenous bolus (250 micrograms) at 24 h and again at 1 h before coronary occlusion (n = 5). Control dogs (n = 7) received equivalent amounts of vehicle. The two groups were similar with respect to occluded bed size, collateral blood flow and rate-pressure product. Fundamental physiological parameters, such as body temperature, arterial pH, PO2 and hematocrit, were within normal limits throughout the experiment. In control dogs, regional myocardial function (assessed as systolic thickening fraction) remained depressed throughout the 4 h reperfusion period, indicating severe myocardial stunning. TGF-beta 1 did not produce any significant improvement in the recovery of regional function; 4 h after reperfusion, paradoxical systolic thinning was still present in both treated and control groups, with thickening fraction being -22.5 +/- 6.1% and -31.0 +/- 5.3% of baseline, respectively (P = N.S.). These results demonstrate that a large dose of TGF-beta 1 given before ischemia fails to attenuate myocardial stunning in the open-chest dog, suggesting that this growth factor does not exert protective effects in the setting of reversible myocardial ischemia/reperfusion injury.
Boundary detection in noisy vector fields

In this paper we propose a novel method for boundary detection of vector fields. The derivation is based on the assumption that the observed vector fields are realizations of a spatially quasi-stationary process and that the vector observations at each pixel site are generated by a parametric probability distribution function. The form of the function is known but its parameters are not. To detect and estimate the locations of the boundaries, we use Bayesian theory and adopt the maximum a posteriori probability (MAP) criterion. It is shown that the criterion is a penalized maximum likelihood, which is composed of two terms. One is a data term that monotonically decreases as the number of hypothesized boundaries increases. The other term is a penalty that penalizes for the complexity of the model used to describe the data. The MAP solution is the one that minimizes the criterion. Simulation results are provided that show the performance of the proposed method. The results on synthesized magnetic resonance (MR) images demonstrate that this technique yields highly accurate estimates of the number of boundaries and their locations even for low contrast-to-noise ratios.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Elucidation of an a and L system for amino acid transport in the human lymphoblast using a membrane filtration technique

Optimum conditions have been established for the measurement of amino acid transport by human lymphoblastoid cell lines using a membrane-filtration technique. The parameters we found to be important for the reproducibility of the method are: the types and combination of filters, the strength of the vacuum applied to the filters and the density of the cultures at the time of harvesting and during uptake and filtration. We found that bovine serum albumin added to phosphate buffered saline (PBS) glucose in which the cells are washed, resuspended and assayed is essential for the maintenance of viability, the prevention of clumping and the retention of the accumulated amino acid. Using this procedure we have characterized two transport systems for the neutral amino acids; an A and an L system, which are similar but not identical to the A and L systems characterized in rodent cell lines. These A and L systems have characteristically lower Km's and Vm's for alanine and phenylalanine, when compared to rodent cell lines. In addition, we find α-AIB to be a poor competitor of alanine and phenylalanine uptake.
Localizing the sources of two independent noises: Role of time varying amplitude differences

Listeners localized the free-field sources of either one or two simultaneous and independently generated noise bursts. Listeners' localization performance was better when localizing one rather than two sound sources. With two sound sources, localization performance was better when the listener was provided prior information about the location of one of them. Listeners also localized two simultaneous noise bursts that had sinusoidal amplitude modulation (AM) applied, in which the modulation envelope was in-phase across the two source locations or was 180° out-of-phase. The AM was employed to investigate a hypothesis as to what process listeners might use to localize multiple sound sources. The results supported the hypothesis that localization of two sound sources might be based on temporal-spectral regions of the combined waveform in which the sound from one source was more intense than that from the other source. The interaural information extracted from such temporal-spectral regions might provide reliable estimates of the sound source location that produced the more intense sound in that temporal-spectral region.
Characterization of Conformational Transitions in Dream Protein using Fluorescence Spectroscopy

DREAM (Down Stream Regulatory Antagonist Modulator) belongs to an important class of calcium binding proteins that are involved in transducing the calcium signal into a biological response in neuronal tissue. DREAM is a unique calcium binding protein that directly binds to DNA and regulates the transcription of prodynorphin and c-fos genes in a calcium dependent fashion. Here we report the conformational transitions in DREAM upon calcium binding by monitoring fluorescence properties of tryptophane residue which is located in proximity to the high affinity calcium binding EF-hand 3. Ca2+ association to the protein leads to the hypsochromic shift in the Trp emission spectrum (max = 338nm) compared to the apo form (max = 343 nm) indicating that the calcium induced conformational transition strongly alters fluorescent probe environment. The changes in the Trp emission spectra are strongly influenced by DREAM concentration confirming that alteration of oligomerization state of DREAM can be readily monitored using fluorescence data. The ligand induced changes in the tryptophan environment were further confirmed by the fluorescence quenching studies using iodide and acrydine quenchers. Trp properties were also analyzed using fluorescence lifetime measurements in frequency domain. In both forms, apo- and Ca2+ bond, the tryptophan lifetime can be described using two exponential decay model , with 1 = 1.5 ns and 1=3.5 ns. The Ca2+ association to protein does not significantly alter tryptophan lifetime but increase the fraction of protein with the lifetime of 1.5 ns.
Rapid diversity and abundance decline in a Caribbean coral reef sponge community

Abstract Sponges are abundant and diverse on coral reefs, and play key functional roles; but virtually nothing is known of their dynamics. This is the first report of coral reef sponge community dynamics documented by a series of censuses in which volume and species of every individual were recorded. At the start of the 14 year study, there were 1395 sponge individuals, representing 39 species in nine orders, and a total sponge volume of 33,721 cm 3 in the censused area of a shallow Caribbean reef in San Blas, Panama. The most striking results of the 5 censuses were steady disappearance of species (51.3%) throughout the study period, and a steep drop in total sponge volume (42.6%). Species in keratose orders and with massive growth forms were lost disproportionately. Sponge losses could not be attributed to predators, physical disturbance (including a hurricane), extreme episodes of other abiotic factors, or disproportionately great loss of rare species due to random fluctuations. Disease may have played a role. High loss rates documented at this and nearby sites could be a local phenomenon, but scattered reports of disease and mass mortality of sponges from other sites suggest these data may reflect region-wide losses. Monitoring programs designed for corals and mobile unitary organisms can miss changes in sponges because very high sponge species diversity, facile fragmentation and fusion, and quick and complete disappearance of dead sponges, impedes perception of changes if there are no prior censuses. Whether or not sponge declines are extensive will remain unknown until repeat censuses have been accomplished at additional sites. Sponges can increase water clarity, bind live corals to the reef frame, and facilitate reef regeneration, suggesting that loss of sponges could accelerate declines of coral reefs.
Gait performance in relation to aortic pulse wave velocity, carotid artery elasticity and peripheral perfusion in healthy older adults

Summary Arterial stiffening is a widely known physiological change that occurs with ageing, but the functional consequences of vascular ageing are unclear. The purpose of this study was to determine whether carotid–femoral pulse wave velocity (PWV), mechanical properties of the carotid and femoral arteries and/or peripheral perfusion was associated with gait performance measured using a 400-m walk test. Twenty-one healthy older (68 ± 5 years) adults without cardiovascular disease participated in this study. Applanation tonometry was used to measure PWV, and Doppler ultrasound was used to measure arterial wall properties of the left common carotid and common femoral artery along with femoral blood flow. The median walk distance in the first 2 min of the test was 585 ft, and the overall gait speed was 1·5 m s−1. Gait performance was inversely correlated with PWV (distance: r = -0·51; speed: r = −0·48; P<0·05) and carotid artery stiffness index β (distance: r = −0·56; speed: r = −0·51; P<0·05) after adjustment for age, body mass index, waist circumference and systolic blood pressure. No significant correlations were found between gait performance and femoral artery stiffness index β or femoral artery blood flow. These results found higher central arterial stiffness, as assessed by segmental arterial stiffness or local arterial wall properties, is associated with lower gait performance in older adults independent of other confounders.
Probability models for pseudorandom test sequences

A probabilistic model for pseudorandom testing of combinational circuits is presented. The expected fault coverage is shown to be accurately approximated as a series of exponentials that depends on the test length and the fault detectabilities. The derivations do not require the pattern generator to have the same number of stages as there are network inputs. >
Improvement of PubMed Literature Searching using Biomedical Ontology

PubMed articles are annotated using the Medical Subject Headings (MeSH) to increase search efficiency. However, MeSH contains limited information on many biomedical domains (e.g., vaccine). Biomedical ontologies may be used to improve PubMed searching capability. This study demonstrates that Vaccine Ontology (VO) can be used to significantly improve PubMed searching efficacy in the vaccine domain. The recall and precision of the ontology-based literature mining approach are analyzed and discussed.
Neutron emission in the fissioning 158Er composite system.

We have measured the spectra and angular distribution of neutrons emitted in coincidence with fission fragments in the following reactions: /sup 16/O+ /sup 142/Nd (E/sub beam/ = 207 MeV), /sup 24/Mg+ /sup 134/Ba (180 MeV), /sup 32/S+ /sup 126/Te (180 MeV), and /sup 50/Ti+ /sup 108/Pd (216 MeV). We decompose neutron emission into components resulting from nonequilibrium emission, emission from the compound system, and emission from the fission fragments. We find that statistical model calculations tend to underestimate the number of neutrons evaporated prior to fission. Incorporating the effects of (1) the finite time until equilibrium fission probability is attained at the saddle point, (2) correction to the Bohr-Wheeler formalism due to nuclear viscosity, and (3) neutron emission during the descent from saddle to scission, improves the agreement with the experimental data. The value of the reduced nuclear dissipation coefficient ..beta.. that is consistent with our data is approximately 6 x 10/sup 21/ s/sup -1/, within the framework of the model we have used.
Indomethacin in submicromolar concentrations inhibits cyclic AMP-dependent protein kinase.

INDOMETHACIN is a potent inhibitor of prostaglandin synthesis1,2, and has been used to demonstrate indirectly the mediation of biological events by prostaglandins. The rationale for this use of indomethacin has been supported when analytical techniques for direct prostaglandin quantitation have been used3,4. There are, however, conflicting data. A role for prostaglandins as the physiological messengers between hormones such as thyrotropin (TSH) and luteinising hormone (LH) and cyclic AMP has been proposed because prostaglandin antagonists inhibit the stimulatory effects of these hormones at their target tissues5,6. A similar role has been proposed in the action of cholera toxin7,8. In both cases, indomethacin failed to prevent the stimulatory effect of these agents on cyclic AMP production, giving support to the opposite view that prostaglandins were not essential intermediates9–11. Paradoxically, indomethacin suppresses, in vivo, thyroid hormone secretion12 and cholera toxin-induced intestinal fluid accumulation13–15. A post-cyclic AMP site of action for indomethacin may explain these discrepancies. To elucidate the role of cyclic AMP-dependent protein kinase and endogenous protein phosphorylation in cholera toxin-induced intestinal secretion16, we have tested the influence of indomethacin on partially purified protein kinase from rabbit ileal mucosa. We report here that indomethacin in submicromolar concentrations inhibits cyclic AMP-dependent protein kinase and endogenous protein phosphorylation.
Treatment of HIV in the CNS: Effects of Antiretroviral Therapy and the Promise of Non-Antiretroviral Therapeutics

The growing recognition of the burden of neurologic disease associated with HIV infection in the last decade has led to renewed efforts to characterize the pathophysiology of the virus within the central nervous system (CNS). The concept of the AIDS-dementia complex is now better understood as a spectrum of HIV-associated neurocognitive disorders (HAND), which range from asymptomatic disease to severe impairment. Recent work has shown that even optimally treated patients can experience not only persistent HAND, but also the development of new neurologic abnormalities despite viral suppression. This has thrown into question what the impact of antiretroviral therapy has been on the incidence and prevalence of neurocognitive dysfunction. In this context, the last few years have seen a concentrated effort to identify the effects that antiretroviral therapy has on the neurologic manifestations of HIV and to develop therapeutic modalities that might specifically alter the trajectory of HIV within the CNS.
Lung phospholipids in the embryonic and immature chicken: Changes in lipid composition and biosynthesis during maturation of the surfactant system

Total phospholipid and its components were measured in lungs of the embryonic chick, and in tissue, lamellar bodies, and lavage fluid after hatching. Phosphatidylcholine (PC), the major phospholipid in surfactant, was fractionated and the amount and fatty acid composition of its disaturated (DSPC) component was determined. The synthetic rates of PC. DSPC, and other choline phospholipids were determined on days 14 and 19 of incubation from incorporation of "C-choline. Choline pool size was also estimated at these times. Phospholipid content of the lung increased most rapidly after day 18 of incubation with the greatest increase in PC. The PC synthesized just prior to breathing was enriched in DSPC, which constituted 45% of PC on day 19 and only 30% on day 14. DSPC content was even lower in embryonic liver and yolk. Incorporation of I4C-choline in vitro into pulmonary PC, Sphingomyelin (Sphingo), and DSPC was greater in birds before breathing (day 19) than in the younger embryos. Choline pool size decreased between days 14 and 19 of incubation, but the synthetic rate of DSPC doubled in this interval. Increased accumulation and biosynthesis of pulmonary PC, Sphingo, and DSPC in lung tissue of the embryo paralleled ap- pearance of lamellar bodies. In 5-6-week-old chickens the major pulmonary phospholipid was also DSPC. In lavage, 70% of PC was DSPC, predominantly dipalmitoyl PC. As in the mammalian lung, PC, especially its DSPC component, forms the major phospholipid of avian surfactant, and the synthesis of DSPC is specifically stimulated prior to breathing.
Benzyl 2,6-dihydroxy-3-nitrobenzoate

Crystals of the title compound, C14H11NO6, were obtained by the reaction of benzyl 2,6-dihydroxy­benzoate with nitric acid and crystallization of the product from ethyl acetate. In the mol­ecule, the nitro group is essentially coplanar with the attached benzene ring [O—N—C—C = 176.75 (11)°], indicating conjugation with the π-electron system. The benzyloxy group of the ester group is cis with respect to the 2-hydroxy group. The crystal structure is stabilized by intra- and inter­molecular hydrogen bonds. The 2-hydroxy group forms an intra­molecular hydrogen bond with the nitro group, and the 6-hydroxy group forms an intra­molecular hydrogen bond with the ester carbonyl function. In addition, there is inter­molecular hydrogen bonding between the 2-hydroxy group of one mol­ecule and the O atom of the 6-hydroxy group of another mol­ecule.
Mechanisms of pathogenesis in Chagas disease

Chagas disease, caused by the obligate unicellular parasite Trypanosoma cruzi, presents itself in a diverse collection of clinical manifestations, ranging from severe, fatal heart and digestive tract pathologies to unapparent or minor alterations that do not compromise survival. Over the years, a number of mechanisms have been proposed to explain the pathogenesis of chagasic tissue lesions, all of which have faced some criticism or been received with skepticism. This article excludes the autoimmunity hypothesis for Chagas disease because it has been extensively reviewed elsewhere, and summarizes the various alternative hypotheses that have been advanced over the years. For each of these hypotheses, an outline of its main tenets and key findings that support them is presented. This is followed by the results and comments that have challenged them and the caveats that stand on their way to wider acceptance. It is hoped that this writing will draw attention to our shortcomings in understanding the pathogenesis of Chagas disease, which, unfortunately, continues to figure among the most serious health problems of the American continent.
Composite Floor Systems under Column Loss: Collapse Resistance and Tie Force Requirements

AbstractThis paper presents a computational assessment of the performance of steel gravity framing systems with single-plate shear connections and composite floor slabs under column loss scenarios. The computational assessment uses a reduced modeling approach, while comparisons with detailed model results are presented to establish confidence in the reduced models. The reduced modeling approach enables large multibay systems to be analyzed much more efficiently than the detailed modeling approaches used in previous studies. Both quasi-static and sudden column loss scenarios are considered, and an energy-based approximate procedure for analysis of sudden column loss is adopted after verification through comparisons with direct dynamic analyses, further enhancing the efficiency of the reduced modeling approach. Reduced models are used to investigate the influence of factors such as span length, slab continuity, and the mode of connection failure on the collapse resistance of gravity frame systems. The adequ...
On the method of images and the asymptotic behavior of first-passage times

This paper studies the large-t behavior of the boundary generated by the method of images for the first-passage-time problem. We show that this behavior is characterized by certain properties of the Laplace transform of the input measure. Such properties also determine the asymptotic behavior of the first-passage-time density. Most of the paper assumes a positive input measure, which generates a concave boundary. The last section, however, discusses a non-positive measure. We obtain a sufficient condition for the boundary to be convex.
Multiple-quantum-well GaAs/AlGaAs in-line fiber intensity modulator

We demonstrate a GaAs/AlGaAs multiple-quantum-well in-line fiber optic intensity modulator. Based on evanescent wave coupling between a GaAs/AlGaAs anti-resonant reflective optical waveguide and a side-polished single mode fiber, this device concept combines the inherent advantages of in- line fiber devices with high-performance GaAs integrated optoelectronics. The GaAs waveguide utilizes distributed Bragg reflector mirrors, which are designed to provide maximum reflection at a given more angle, to phase-match to the low-index fiber. Intensity modulation of the transmitted light through the fiber is achieved by changing the complex propagation constant of the GaAs waveguide through the quantum-confined Stark effect. Typical device shows an on/off ratio of 4:1, with an applied voltage of 9V. Calculations show that with a longer interaction region, an on/off ratio of more than 40dB is achievable with the same applied voltage.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Monthly Update: Anti-infectives: VAQTA: Merck's hepatitis A vaccine, purified, inactivated

The safety/tolerability profile, immunogenicity and protective efficacy of VAQTA, Merck's hepatitis A vaccine, purified, inactivated, are based on studies of 18,239 vaccinees; 12,000 2–17 years and 6239 18 years and older. To date, no vaccinee has had any serious vaccine-related adverse experience. In placebo-controlled studies, the local and systemic adverse experience profile has been indistinguishable from that of placebo alum diluent. The goal of ≥ 95% seropositivity was achieved within 4 weeks after one im dose of 25 units (2–17 year olds, 1 U ≥1 ng of purified viral protein; 18 –76 year olds, 50 U). Anamnestic responses to a booster given at 6,12 or 18 months revealed that the priming dose conferred immune memory in > 99% of vaccinees, regardless of pre-booster antibody level.Protective efficacy of 100% starting at least as early as day 21 after a single dose was proven in a randomised, double-blinded field trial among 2–16 year olds in Monroe, NY. Although prior to the vaccine trial cases occurred ...
Towards a method for assessing resilience of complex dynamical systems

System survivability is one of the key requirements for the conceptual design of an Integrated Reconfigurable Intelligent (IRIS) system. Current approaches in survivability engineering may not effectively address the challenges in designing revolutionary, large scale complex and multi-capable systems. The main objective of this study is to investigate the concept of resilience in the context of system safety and survivability and suggest a technique for assessing resilience in systems engineering. Resilience is expected to be the enabler for integrating safety and survivability in the early conceptual design. For this purpose, a small scale cooling network system architecture has been utilized to demonstrate the technique, both for a 32-valve baseline, as well as for six other configurations. The application of the technique allowed for the comparative assessment and tradeoff investigation of resilience function capacities, as well for the identification of solution feasibility, under adaptability and robustness constraints.
TASK-1 Potassium Channels Limit Pancreatic α-Cell Calcium Influx and Glucagon Secretion

Glucose regulation of pancreatic α-cell Ca(2+) entry through voltage-dependent Ca(2+) channels is essential for normal glucagon secretion and becomes defective during the pathogenesis of diabetes mellitus. The 2-pore domain K(+) channel, TWIK-related acid-sensitive K(+) channel 1 (TASK-1), is an important modulator of membrane voltage and Ca(2+) entry. However, its role in α-cells has not been determined. Therefore, we addressed how TASK-1 channels regulate α-cell electrical activity, Ca(2+) entry, and glucagon secretion. We find that TASK-1 channels expressed in human and rodent α-cells are blocked by the TASK-1 channel inhibitor A1899. Alpha-cell 2-pore domain K(+) currents were also significantly reduced after ablation of mouse α-cell TASK-1 channels. Inhibition of TASK-1 channels with A1899 caused plasma membrane potential depolarization in both human and mouse α-cells, which resulted in increased electrical excitability. Moreover, ablation of α-cell TASK-1 channels increased α-cell electrical excitability under elevated glucose (11 mM) conditions compared with control α-cells. This resulted in significantly elevated α-cell Ca(2+) influx when TASK-1 channels were inhibited in the presence of high glucose (14 mM). However, there was an insignificant change in α-cell Ca(2+) influx after TASK-1 inhibition in low glucose (1 mM). Glucagon secretion from mouse and human islets was also elevated specifically in high (11 mM) glucose after acute TASK-1 inhibition. Interestingly, mice deficient for α-cell TASK-1 showed improvements in both glucose inhibition of glucagon secretion and glucose tolerance, which resulted from the chronic loss of α-cell TASK-1 currents. Therefore, these data suggest an important role for TASK-1 channels in limiting α-cell excitability and glucagon secretion during glucose stimulation.
Effect of Carrier Offset on the Classification of Phase Shift Keying Modulation using the Subtraction of Two Consecutive Signal Values

In this paper we study the effect of carrier offset on a feature distinguishing binary phase shift keying and quadrature phase shift keying. The feature is based on the subtraction of two consecutive signal values and the kurtosis of the absolute value of this subtraction. The paper compares performance of the proposed feature to a cumulant based feature when both are used in a support vector machine classifier. Also the paper compares the proposed-feature based classification to the maximum likelihood classification and to the quasi-log-likelihood ratio classifier. The simulation results showed that the proposed feature classifier has a robust performance with respect to carrier offset compared to the other above mentioned classifiers.