cssi/SciSciGPT-SciSciNet huggingface dataset:
Sphincter of Oddi dysfunction: role of sphincterotomy

Sphincter of Oddi dysfunction (SOD) is one of the causes of post-cholecystectomy syndrome and biliary pain and is a challenge from both the diagnostic and therapeutic points of view. Sphincter of Oddi dysfunction is typically diagnosed months to years after cholecystectomy. Continued biliary type pain after cholecystectomy may occur in as many as 10–20% of patients. Ten percent or more of these patients may eventually be shown to have SOD. The syndrome is often associated with a variety of other gastrointestinal disorders thought to be caused by dysmotility. According to the Milwaukee classification, patients with biliary pain can be divided into three types. Type I patients show all the objective signs suggestive of a disturbed bile outflow (i.e. elevated liver function tests, dilated common bile duct and delayed contrast drainage during endoscopic retrograde cholangiopancreatography). Type II patients have biliary type pain along with one or two of the criteria from type I. Type III patients have biliary pain only, with no other abnormalities. The present paper will focus primarily on SOD syn-drome, papillary stenosis and the diagnostic and therapeutic approaches, in particular endoscopic sphincterotomy.
Intermolecular 1H{19F} NOEs in Studies of Fluoroalcohol-Induced Conformations of Peptides and Proteins

Abstract Mixtures of fluorinated alcohols and water can selectively stabilize certain secondary structures of peptides and proteins. Such mixtures may also be of use in solubilizing hydrophobic or membrane-bound proteins. We show that intermolecular dipolar interactions between the fluorine nuclei of such solvents and the protons of a dissolved protein lead to readily detected 1 H{ 19 F} nuclear Overhauser effects. These NOEs can potentially provide information about solvent exposure of particular groups as well as indicate the formation of long-lived fluoroalcohol–solute complexes. Results obtained with HEW lysozyme in solutions containing trifluoroethanol illustrate these possibilities.
Theory of Reflection by Volume Gratings and Boundaries: Polarization and Interference Properties

Fresnel and volume-holographic reflections are studied. Hyperbolic arctan of reflection amplitude is shown to be the sum of two contributions: due to impedance and refractive index modulations. Mutual influence of Fresnel and volume reflections revealed.
The frictional behavior of serpentinite: Implications for aseismic creep on shallow crustal faults

Serpentine is common in many active faults and may be responsible for aseismic creep along segments of these faults. To test this, we have conducted a series of velocity stepping experiments to determine the frictional velocity dependence of serpentinite. We slid initially bare, rough surfaces of antigorite serpentinite at room temperature, with velocities from 0.0032 to 10.0 μm/s (1.0×102 to 3.2×105 mm/yr) and normal stresses from 25 to 125 MPa. We find that the velocity dependence of serpentinite undergoes a transition from velocity weakening at fast loading velocities to velocity strengthening at slow velocities and that this change is accompanied by other changes in the constitutive behavior. These results suggest that serpentinite should not be the site of instability initiation during sliding at plate velocities, but may permit propagation of unstable slip initiated elsewhere.
Inheritance of Size and Shape in a Population of Darwin's Finches, Geospiza conirostris

Mass, wing length, tarsus length and four bill dimensions were measured on adult Large Cactus Ground Finches ( Geospiza conirostris ) and their offspring in a field study on Isla Genovesa, Galapagos. Heritabilities of these traits were determined by regressing family mean offspring values on midparent values. Principal components analysis was used to provide a multivariate characterization of size and shape, and component scores were used in heritability analysis. Morphological traits were highly heritable. All heritabilities of univariate traits exceeded 0.65, and the arithmetic mean was 0.84. Principal component 1 provides a measure of overall body size; this has a high heritability (0.79). Principal component 2, a bill-pointedness shape factor, also has a high heritability (0.92). Indirect evidence suggests the possibility of a small influence of genotype–environment correlation on the heritability estimates for two traits, mass and bill length. The overall conclusion is that there is a strong potential for evolutionary change in morphology in this population. The population may have been subject to disruptive selection recently, followed by stabilizing selection. Genetic correlations between measured traits were moderately large (mean 0.54) and all were positive. In several respects G . conirostris is intermediate between two other congeneric species, G . fortis and G . scandens . Heritabilities and genetic correlations appear to be higher in G . fortis and lower in G . scandens . These differences are associated with different feeding niches, different degrees of predictability of food resources and different types of selection pressures to which the species are subjected.
Role of antiprogestational therapy for meningiomas

Epidemiological evidence, including the greater incidence of female patients, a positive association with pregnancy, and a positive association with breast cancer suggested a role for female sex hormones (and hormonal modulation) in regulating the growth of meningioma. The detection of hormone receptors on meningioma specimens provided a mechanism for this effect. However, unlike breast cancer, progesterone receptors (not oestrogen receptors) predominate in meningioma. Clinical trials with anti-oestrogens have shown little effect while trials with progesterone agonists have shown no effect or possible stimulation of meningioma growth. Three trials have now indicated an inhibitory activity of the antiprogestational agent mifepristone. In the largest of these trials, 28 patients received daily oral mifepristone for up to 62 months with a suggestion of response in eight patients. Long-term therapy has been well tolerated. Adverse events include fatigue, hot flushes, gynaecomastia/breast tenderness, skin rash, cessation of menses and decrease in libido. Increases in cortisol and thyroid-stimulating hormone are the most striking endocrine changes. A randomized double-blind placebo-controlled phase III trial is underway to confirm the activity of mifepristone in unresectable meningioma.
Effect of residual H 2 O on epitaxial AlN film growth on 4H-SiC by alternating doses of TMA and NH 3

Abstract An epitaxial AlN film was synthesized on 4H-SiC using alternate doses of trimethyl aluminum (TMA) and anhydrous ammonia (a-NH3) at 540 °C. The growth per cycle (GPC) at the temperature was limited to 0.27 A/cycle under the minute amount of residual H2O. The formation of an inert Al–O–Al bond generated by the recombinative desorption of two Al–OH species to produce H2O has been proposed as a possible reason for the low deposition rate. By eliminating any present moisture in the reactor system, the GPC increased to 1.5 A/cycle. The suppression of the OH group generation at 540 °C made it possible to deposit nearly stoichiometric AlN film which has the crystallinity with the preferred orientation along the (0 0 0 1) direction on 4H-SiC templates. The measured RMS surface roughness was comparable to that achieved by molecular beam epitaxy (MBE).
Vapor pressures and sublimation enthalpies of seven heteroatomic aromatic hydrocarbons measured using the Knudsen effusion technique.

Abstract The vapor pressures of seven heteroatom-containing cyclic aromatic hydrocarbons, ranging in molecular weight from (168.19 to 208.21) g · mol−1 were measured over the temperature range of (301 to 486) K using the isothermal Knudsen effusion technique. The compounds measured include: anthraquinone, 9-fluorenone, 9-fluorenone oxime, phenoxazine, phenoxathiin, and 9H-pyrido[3,4-b]indole. These solid-state sublimation measurements provided values that are compared to vapor pressures of parent aromatic compounds (anthracene and fluorene) and to others with substituent groups in order to examine the effects of alcohol, ketone, pyridine, and pyrrole functionality on this property. The enthalpies and entropies of sublimation for each compound were determined from the Clausius–Clapeyron equation. Though there is no consistent trend in terms of the effects of substitutions on changes in the enthalpy or entropy of sublimation, we note that the prevalence of enthalpic or entropic driving forces on vapor pressure depend on molecule-specific factors and not merely molecular weight of the substituents.
The effect of molar volume on the swelling of poly(dimethylsiloxane) in fluorocarbon fluids

The vapour sorption of three fluorocarbon fluids (tetrafluoroethane, chlorotetrafluoroethane, and heptafluoropropane) has been measured in crosslinked and uncrosslinked poly(dimethylsiloxane) as a function of the temperature in the interval 35–105°C. For a given solvent, the swelling activity parameter, S, for the solvent/crosslinked polymer system decreases as both the degree of swelling and the temperature increase. The range of experimental conditions examined allowed consideration of S for different solvents, but constant molar volume V1. Plots of S as a function of degree of swelling can be reduced to families of curves at constant V1 for the three solvents studied here. The dependence of S on solvent quality and temperature is then encompassed in its variation with V1.
Tensile behavior of free-standing gold films. Part I. coarse-grained films

The room temperature mechanical behavior of free-standing, coarse-grained gold films (grain size greater than 1.5 μm) was investigated by uniaxial tensile testing. Use of different deposition conditions resulted in films with a variety of microstructures. In addition, some of the free-standing films were also subjected to high temperature anneals to further alter their microstructures. With the exception of low ductility, the mechanical behavior of the films was generally consistent with what would be expected from large-scale gold specimens having similar grain size.
Failure Resilient Heterogeneous Parallel Computing Across Multidomain Clusters

We propose lightweight middleware solutions that facilitate and simplify the execution of failure-resilient Message Passing Interface (MPI) programs across multidomain clusters. The system described in this paper leverages H2O, a distributed metacomputing framework, to route MPI message passing across heterogeneous aggregates located in different administrative or network domains. MPI communication is aided by a specially written H2O pluglet; messages that are destined for remote sites are intercepted and transparently forwarded to their final destinations. We demonstrate that the proposed technique is indeed effective in enabling communication by MPI programs across distinct clusters and across firewalls. Only marginally lowered performance was observed in our tests, and we believe the substantially increased functionality would compensate for this overhead in most situations. In addition to enabling multicluster communications, we note that with the increasing size and distribution of metacomputing environments, fault tolerance aspects become critically important. We argue that the fault tolerance model proposed by FT-MPI fits well in geographically distributed environments, even though its current implementation is confined to a single administrative domain. We describe extensions to overcome these limitations by combining FT-MPI with the H2O framework. Our holistic approach allows users to run fault-tolerant MPI programs on heterogeneous, geographically distributed shared machines, without sacrificing performance and with minimal involvement of resource providers.
Expression of the F84.1 glycoprotein in the spinal cord and cranial nerves of the developing rat.

Abstract The monoclonal antibody designated as F84.1 was used for an immunohistochemical study of the developing rat nervous system. The most prominent neural components recognized by F84.1 are motor and sensory components of the spinal cord and cranial nerves. F84.1 is first detected in the dorsal root ganglia of embryonic day 11 spinal cord. The expression in the dorsal roots persists in the adult. In contrast, a more transient expression of F84.1 is found in the spinal motor system. F84.1 labels primary neurons of cranial nerves V, VIII, IX and X. F84.1 is also expressed by the non-neuronal cells of the notochord and the floor plate. Immunoprecipitation experiments from several types of cells in culture show that the F84.1 antigen is a cell-surface glycoprotein with a molecular weight of 90–105 kDa. An analysis of the amino terminal sequence demonstrates that the F84.1 antigen is similar to the chick cell adhesion molecule SC1/DM-GRASP, a member of the immunoglobulin superfamily. The pattern of expression of F84.1 in the rat differs in several aspects from that of the chick molecules, leaving a possibility that F84.1 may be a variant of SC1/DM-GRASP.
Relocating dislocations in a wilderness setting: use of hypnosis

Joint dislocations or fracture/dislocations of extremities are disabling injuries in wilderness areas, both to the individual patient and to the patient's wilderness group. Recognizing the beneficial effect of early relocation of dislocations, wilderness practitioners are now encouraged to attempt joint relocations in the backcountry setting. To be successful, adequate sedation/relaxation must be achieved. Hypnosis was applied in six patients with shoulder or ankle dislocations. Successful relocations were accomplished in five of the patients. Those with upper extremity dislocations were immediately able to walk out with minimal assistance after relocation.
Introduction to Culture at Large Forum with George Lipsitz: Social Warrants and Rethinking American Culture

“Rethinking American Culture” was a forum featuring the work of George Lipsitz in a dialogue between American Studies and anthropology about the ways in which “new forms of commercial patterns and practices, new movements of people and products, and new communications technologies are producing new ways of studying culture.” This dialogue addresses the struggles over the social warrants of U.S. culture in the 21st century and how historians and anthropologists might best describe and analyze such warrants and reconstitute these fields, both of which are under pressure in a present “moment of danger” made all the more visible by the aftermath of Hurricane Katrina in New Orleans, Louisiana.
Real Estate Investment Analysis: New Developments in Traditional Leverage Concepts

The advantages of utilizing leverage in real estate investments has received much attention in the past, but little guidance has been offered that shows the investor the most opportune leverage position for a given investment alternative. Traditional leverage concepts are explored in this article, prior to developing a financial indifference point model and a continuous-function degree of financial leverage (DFL) formula. The indifference point and DFL as shown here are relatively simple to calculate and provide additional insights into risk, return and leverage concepts for real estate investments.
The Meaning of Race and Violence in Grand Theft Auto San Andreas

This research study investigates how youths actually play Grand Theft Auto: San Andreas and what meanings they make from it. This study finds that players use their own experiences and knowledge to interpret the game—they do not passively receive the games' images and content. The meanings they produce about controversial subjects are situated in players' local practices, identities, and discourse models as they interact with the game's semiotic domain. The results suggest that scholars need to study players in naturalistic settings if they want to see what “effects” games are having on players.
Onchocerciasis — A potential revolution in its treatment

Onchocerciasis is a major blinding disease affecting at least 28 million people in Africa and Latin America. Although a large-scale vector control program has been highly successful in limiting transmission of infection in West Africa, there has not been a satisfactory form of treatment available for those already infected or those living in other areas. Despite the fact that two drugs, diethylcarbamazine and suramin, are active against the filarial parasite that causes onchocerciasis, their use is severely limited by their toxicity and the reaction they induce. A newly developed drug, ivermectin, appears to offer a major revolution in the treatment of onchocerciasis. In a series of clinical trials, ivermectin has been shown to be an extremely effective microfilaricide which induces only minimal side effects. Ivermectin is given as a single oral dose which can be repeated on an annual basis. In view of its safety and efficacy and its ease of administration, it seems likely that ivermectin will be suitable for use in mass chemotherapy programs against onchocerciasis.
Thermal time constants in differential scanning calorimetry

Abstract We have examined thermal gradients in a differential scanning calorimeter. We quantified, as a function of sample heat capacity, the thermal lag, Δ T between sample and calorimeter. We found that Δ T = β(τ x + R 0 C s )+ Δ T c ; where β is the heating rate, Δ T c is a constant, C s is the total heat capacity of the sample and pan, R 0 is the thermal resistance between sample and calorimeter, and τ x is an instrumental time constant. We observed that the value of Δ T c depended on both the sample size and the thermal resistance between sample and calorimeter. Analysis of changes in Δ T c with changes in R 0 led to an order of magnitude estimate of 3 mcal s −1 for the rate of heat flow between calorimeter and sample when the calorimeter is held at a constant temperature near 500 K. We discuss the effect of this heat flux on the accuracy of the temperature scale.
Discriminative stimulus effects of alcohol in humans

Abstract The discriminative stimulus effects of alcohol were examined in 11 healthy moderate alcohol users. Study days occurred 5 days per week for 12–25 total days. Each day, participants completed visual-analog reports of drug effect and drug-discrimination tasks at 30-min intervals for 2.5 h following oral alcohol administration. Participants completed three phases. During the training phase, which occurred on the first 4 study days, participants were trained to discriminate color-coded placebo and alcohol doses (0 vs. 0.45 g per liter of body water (g/lbw)). Participants then completed a control phase, during which accurate drug-discrimination performance was verified. Finally, participants completed a testing phase, during which both training and intermediate doses (0.15 and 0.30 g/lbw) were administered. During the testing phase, 25 and 100% of responses occurred on the alcohol key at the 0- and 0.45-g/lbw doses, respectively, indicating that discrimination responding remained intact. At the low dose (0.15 g/lbw), 25% of the subjects responded on the alcohol key, whereas 75% of the subjects responded on the alcohol key at the moderate dose (0.30 g/lbw), indicating dose-related generalization to the training doses. These results confirm cross-species generality in the discriminative stimulus effects of alcohol, and further establishes the utility of human laboratory drug-discrimination procedures for analysis of the functional effects of alcohol.
Neural correlates of learning in an electrocorticographic motor-imagery brain-computer interface.

Human subjects can learn to control a one-dimensional electrocorticographic (ECoG) brain-computer interface (BCI) using modulation of primary motor (M1) high-gamma activity (signal power in the 75–200 Hz range). However, the stability and dynamics of the signals over the course of new BCI skill acquisition have not been investigated. In this study, we report three characteristic periods in evolution of the high-gamma control signal during BCI training: initial, low task accuracy with corresponding low power modulation in the gamma spectrum, followed by a second period of improved task accuracy with increasing average power separation between activity and rest, and a final period of high task accuracy with stable (or decreasing) power separation and decreasing trial-to-trial variance. These findings may have implications in the design and implementation of BCI control algorithms.
Developmental changes in rat adrenal tyrosine hydroxylase, dopamine-β-hydroxylase and catecholamine levels: Effect of denervation☆

Abstract Developmental changes in rat adrenal tyrosine hydroxylase, dopamine-β-hydroxylase, and catecholamine levels: effect of denervation. Levels of adrenal tyrosine hydroxylase, dopamine-β-hydroxylase, and catecholamines were found to be dependent upon both the age and the innervation of the adrenal gland. During growth from 8 to 15 wk of age, tyrosine hydroxylase, dopamine-β-hydroxylase, and catecholamines increased by 51, 33, and 57%, respectively, in intact adrenal glands. Denervating the left adrenal gland at 8 wk of age completely prevented the increases seen in the innervated glands. In younger animals, during growth from 4 to 12 wk of age, tyrosine hydroxylase activity increased 2- to 3-fold, dopamine-β-hydroxylase activity increased about 2-fold, and catecholamine levels increased 3- to 5-fold in intact adrenal glands. Denervation of the adrenal gland at 23 days of age markedly depressed the increase in enzyme activities and catecholamines to approximately one half that seen in innervated glands.
How Industrial Digital Controllers can Cause Process Cycling

Under certain conditions, digital controllers can be the cause of process cycling. This paper explains why this can occur, how to analyze if a given controller application can cycle and how to prevent it. It also discusses how this same effect can cause errors in loop tuning.
Tissue Polarity-Dependent Control of Mammary Epithelial Homeostasis and Cancer Development: an Epigenetic Perspective

The basoapical organization of monolayered epithelia is defined by the presence of hemidesmosomes at the basal cellular pole, where the cell makes contacts with the basement membrane, and tight junctions at the opposite apical pole. In the mammary gland, tight junctions seal cell–cell contacts against the lumen and separate the apical and basolateral cell membranes. This separation is critical to organize intracellular signaling pathways and the cytoskeleton. The study of the impact of the highly organized apical pole, and notably apical polarity regulators (Crb complex, Par complex, and Scrib, Dlg, Lgl proteins) and tight junction proteins on cell phenotype and gene expression has revealed an intricate relationship between apical polarity and the cell nucleus. The goal of this review is to highlight the role of the apical pole of the tissue polarity axis in the epigenetic control of tissue phenotype. The organization of the apical pole and its importance in mammary homeostasis and tumorigenesis will be emphasized before presenting how apical polarity proteins impact gene expression indirectly, by influencing signal transduction and the location of transcription regulators, and directly, by participating in chromatin-associated complexes. The relationship between apical polarity and cell nucleus organizations might explain how apical polarity proteins could switch from nuclear repressors to nuclear promoters of cancerous behavior following alterations in the apical pole. The impact of apical polarity proteins on epigenetic mechanisms of gene expression will be discussed in light of increased evidence supporting a role for apical polarity in the fate of breast neoplasms.
Ion beam induced modification of nanolayers containing vanadium and silica

Abstract Layers of vanadium monoxide (VO) and pure silica were alternately deposited on a silica substrate. Similarly, layers of V2O3 and pure silica were alternately deposited on a silica substrate. The interfaces between the codeposited layers and pure silica layers were at no time exposed to air. Each sample was bombarded by 5.0 MeV Si beam at fluences between 1015 and 1017 ions/cm2 at room temperature. Optical properties were measured using Optical Absorption Photospectrometry (OAP). The elemental distribution was measured using Rutherford Backscattering Spectrometry (RBS) at each step of Si bombardment. A different piece of each layered sample was annealed at temperatures between 100 and 1100 °C steps, for 1 h in argon environment. OAP and RBS were observed after each temperature. The dramatic apperance of an optical absortion resonance at 410 nm after heat treatment to 600 °C indicates that vanadium nanocrystals form in silica at that temperature. An ion bomdarment induced mixing coefficient is derived and experimentally evaluated for vanadium in silica. It is observed to increase with the accumulated fluence and multilayered samples.
GROWTH OF VITAMIN B12‐REQUIRING MARINE DIATOMS IN MIXED LABORATORY CULTURES WITH VITAMIN B12‐PRODUCING MARINE BACTERIA12

SUMMARY The vitamin B12 requirement of several marine diatoms can be satisfied in B12−limited laboratory cultures by heterotrophic marine bacteria isolated from the same waters and from sediments. The bacteria can utilize diatom excretory products, or the remains of dead diatom cells, in the production of the vitamin. The growth of 12 B121− requiring diatoms (7 genera) in mixed cultures with 14 different bacteria (without added B12) was compared to the growth of those same diatoms in axenic cultures with excess added B12. Diatom growth was generally rapid in the first few days, followed by sustained, slower growth. The diatom yields in mixed cultures ranged from 0.8 to 84% of the yields in axenic cultures with added B12. In a detailed study of one mixed culture, increases in diatom densities were paralleled by increases in cell densities of the bacterium during the first few days of exponential diatom growth. During the period of slow diatom growth, when diatom densities oscillated but steadily increased, the decreases in diatom densities were associated with increased bacterial growth. This suggests that death of a fraction of the B12-limited diatom population releases sufficient organic matter to stimulate growth of the bacteria and their subsequent excretion of B12; this B12 in turn stimulates further growth of the diatoms. Diatom-bacteria interactions leading to the production of B12 may be important in maintaining viable populations of B12-requiring diatoms in nutrient-poor waters during periods between blooms, when conditions are unfavorable for rapid growth.
Metacognition and part-set cuing: Can interference be predicted at retrieval?

Although prior research has examined predictions of memory performance under conditions of interference at encoding, predictions of memory performance have not been examined for interference introduced via cues at retrieval. This was investigated in the present study by exposing participants to a random subset of to-be-recalled items just prior to retrieval (part-set cuing) and then eliciting an overall prediction of memory performance. Across three experiments, participants in part-set cuing conditions recalled proportionally fewer items than did participants who were not exposed to any cues. However, participants were unable to predict the detrimental effect of part-set cues on memory performance in either a semantic (Experiment 1) or an episodic (Experiment 2) memory task. Predictions were better calibrated after practice with part-set cuing, and there was evidence that prior experience with part-set cuing transferred to predictions made for a different part-set cuing task (Experiment 3). This suggests that only under some conditions are participants sensitive to the diminished accessibility of memories wrought by part-set cues and illustrates situations in which participants are or are not aware of variables at retrieval that influence memory performance.
Superconductivity and cobalt oxidation state in metastable Na x CoO 2− δ∙ y H 2 O (x≈ 1∕ 3; y≈ 4 x)

We report the synthesis and superconducting properties of a metastable form of the known superconductor Na{sub x}CoO{sub 2}{center_dot}yH{sub 2}O (x{approx_equal}1/3;y{approx_equal}4x). We obtained this metastable cobaltate superconductor due to the unique way it was synthesized. Instead of using the conventional bromine-acetonitrile mixture for the Na{sup +}-deintercalation reaction, we use an aqueous bromine solution. Using this method, we oxidize the sample to a point that the sodium cobaltate becomes unstable, leading to formation of other products if not controlled. This compound has the same structure as the reported superconductor, yet it exhibits a systematic variation of the superconducting transition temperature (T{sub c}) as a function of time. Immediately after synthesis, this compound is not a superconductor, even though it contains appropriate amounts of Na{sup +} and H{sub 2}O. The samples become superconducting with low T{sub c} values after {approx}90 h. T{sub c} continually increases until it reaches a maximum value (4.5 K) after about 260 h. Then T{sub c} drops drastically, becoming nonsuperconducting approximately 100 h later. Corresponding time-dependent neutron powder diffraction data shows that the changes in superconductivity exhibited by the metastable cobaltate correspond to slow formation of oxygen vacancies in the CoO{sub 2} layers. In effect, the formation of thesemore » defects continually reduces the cobalt oxidation state causing the sample to evolve through its superconducting life cycle. Thus, the dome-shaped superconducting phase diagram is mapped as a function of cobalt oxidation state using a single sample. The width of this dome based on the formal oxidation state of cobalt is very narrow--approximately 0.1 valence units wide. Interestingly, the maximum T{sub c} in Na{sub x}CoO{sub 2}{center_dot}yH{sub 2}O occurs when the cobalt oxidation state is near +3.5. Thus, we speculate that the maximum T{sub c} occurs near the charge ordered insulating state that correlates with the average cobalt oxidation state of +3.5.« less
High-speed network for delivery of education-on-demand

A project to investigate the feasibility of delivering on-demand distance education to the desktop, known as the Asynchronous Distance Education ProjecT (ADEPT), is presently being carried out. A set of Stanford engineering classes is digitized on PC, Macintosh, and UNIX platforms, and is made available on servers. Students on campus and in industry may then access class material on these servers via local and metropolitan area networks. Students can download class video and audio, encoded in QuickTimeTM and Show-Me TVTM formats, via file-transfer protocol or the World Wide Web. Alternatively, they may stream a vector-quantized version of the class directly from a server for real-time playback. Students may also download PostscriptTM and Adobe AcrobatTM versions of class notes. Off-campus students may connect to ADEPT servers via the internet, the Silicon Valley Test Track (SVTT), or the Bay-Area Gigabit Network (BAGNet). The SVTT and BAGNet are high-speed metropolitan-area networks, spanning the Bay Area, which provide IP access over asynchronous transfer mode (ATM). Student interaction is encouraged through news groups, electronic mailing lists, and an ADEPT home page. Issues related to having multiple platforms and interoperability are examined in this paper. The ramifications of providing a reliable service are discussed. System performance and the parameters that affect it are then described. Finally, future work on expanding ATM access, real-time delivery of classes, and enhanced student interaction is described.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The Effect of Increased Processivity on Overall Fidelity of Human Immunodeficiency Virus Type 1 Reverse Transcriptase

We previously reported that two insertions of 15 amino acids in the β3–β4 hairpin loop of fingers subdomain of HIV-1NL4-3 RT confer an increased polymerase processivity. The processivity of human immunodeficiency virus (HIV) reverse transcriptase (RT) is thought to influence the fidelity of HIV-1 RT, which tends to create errors at template sites with high termination probability. Employing the two insertion variants of HIV-1 RT (FE20 and FE103), we examined the relationship between processivity, overall fidelity and error specificity. Although the overall mutation rate was unaffected by increased processivity, one of the mutants, FE103, generated significantly fewer frameshift errors. The other mutant, FE20, generated errors at hotspots not previously observed for HIV-1 RT. Our results indicate that an increase in the polymerase processivity of HIV-1 RT does not necessarily result in a decreased mutation rate and confirm that changes in processivity alter the sequence context in which the errors are made. Furthermore, our results also reveal that the mutation frequency obtained via in vitro gap-filling reactions with wild-type HIV-1NL4-3 RT is only 2-fold higher than that obtained via a single cycle infection assay using the same, wild-type HIV-1NL4-3 RT sequence as part of the helperpol function [Mansky and Temin: J Virol 69:5087–5094;1995].
Exploring the Impact of Demographic, Personality, and Job Reattainment Variables on Unemployment-Delayed Retirement Intent

A diverse sample of unemployed respondents completed an online survey investigating the impact of demographic, personality, and job reattainment variables on their unemployment-delayed retirement intent (UDRI). The authors found that being unemployed for a longer time period, older, having more dependents to support, in greater denial of recent job loss, as well perceiving poor job re-attainment prospects were each related to higher UDRI. Poor job reattainment was measured using two separate items: perceptions of obtaining another job that would not be as good and taking time, and perceptions that there was no end in sight to unemployment. The results have implications for Employee Assistance Plans.
Combined Modality Treatment of Adductor Spasmodic Dysphonia

Summary Introduction The hallmark characteristic of adductor spasmodic dysphonia (ADSD) is irregular and uncontrollable spasms within the intrinsic laryngeal muscles, resulting in erratic disruption of normal voicing. Methods Using a random assignment and the inclusion of a behavioral sham to determine the effect of voice therapy after initial botulinum toxin type A (BTX-A) injections for ADSD, this study examined duration of injection benefit, perceived vocal quality of life from the Voice-Related Quality of Life (V-RQOL) scale, acoustic measures of vocal instability, and perceptual ratings of voice quality. Measures of these variables were collected before initial injection; 3, 7, and 12 weeks postinjection; and immediately before reinjection. Thirty-one individuals with ADSD participated in this study. One-third received no further intervention after BTX-A injection, one-third received a standard 5-week course of voice therapy after BTX-A injection, and one-third received a 5-week course of sham voice therapy after BTX-A injection. Results and Conclusions Significant effects were observed on perceived quality of life and acoustic variables for all participants, over time. Participants who received voice therapy after BTX-A injection did not experience longer injection effect duration or significantly greater improvements in V-RQOL or acoustic variables than participants in BTX-A only or BTX-A plus sham therapy groups. Additionally, perceptual ratings of voice quality improved for all participants in response to BTX-A injection. For participants in this investigation, undertaking voice therapy did not appear to exert significant beneficial effects on the variables of interest.
Optimal immediately-decodable inter-session network coding (IDNC) schemes for two unicast sessions with hard deadline constraints

In this paper, we study inter-session network coding for sending two unicast sessions over an unreliable wireless channel. Each unicast session transmits a stored video file, whose packets have hard sequential deadline constraints. We first characterize the capacity region (with inter-session network coding) for the transmission rates of the two unicast sessions under heterogeneous channel conditions and heterogeneous deadline constraints. We then develop immediately-decodable network coding (IDNC) schemes for controlling packet transmissions for the unicast sessions subject to hard deadline constraints. In contrast to our prior work that focuses on a single multicast session with homogeneous channel conditions and deadline constraints, the design and performance analysis of the IDNC scheme is much more complicated for unicast-sessions because of the asymmetry due to heterogeneous channel conditions and heterogeneous deadlines. Nonetheless, we establish the asymptotic optimality of the proposed IDNC scheme when the file sizes are sufficiently large.
Collagen matrix alignment using inkjet printer technology

Collagen fiber orientation plays an important role in many cell properties and actions in vivo. Collagen and other matrix proteins are aligned in many tissues during normal functioning. For example, cardiomyocytes align in the heart to produce a synchronously beating tissue. The extra-cellular matrix environment, including collagen, is aligned along the cells. This matrix helps with cell adhesion and the alignment of the fibers also contributes to the anisotropic mechanical property of the tissue. While it is easy to replicate randomly oriented collagen in vitro, it is much more difficult to create aligned collagen matrices for cell culture. In this work, a novel inkjet printer-based collagen alignment technique was established. A 1 mg/ml rat tail collagen type I solution was printed, using a modified HP DeskJet 500 printer, onto plasma cleaned and UV sterilized glass slides. The collagen was printed in an eight line pattern, designed in Microsoft Word with 87.5 μm by 23.1 mm lines. The pattern was printed three successive times on each slide to complete the alignment. Immunofluorescence imaging of primary antibodies specific to collagen type I indicated that the heat involved in the printing process was not great enough to denature the collagen. The extent of collagen alignment was quantified using atomic force microscopy and compared to random collagen films and collagen films aligned using a mechanical scraping method. Additionally, neonatal rat cardiomyocytes were cultured on the aligned matrices. These cells require extracellular matrix alignment to maintain their in vivo-like phenotype during in vitro culture. The cells grew along the lines of collagen and coordinated beating, indicating the success of the aligned matrix. This collagen alignment technique is cheap, fast, precise, and easy to use in comparison to other current techniques. It can be used to align collagen on any type of substrate, such as a gel, which makes it a useful tool in many applications. This technique may also be used to align other extra-cellular matrix proteins and could even be used to create a three dimensional construct with varying fiber orientations.
6-Thioguanine and zebularine down-regulate DNMT1 and globally demethylate canine malignant lymphoid cells.

The antimetabolite 6-thioguanine (6-TG) has been used to treat both human and canine lymphoid malignancies. 6-TG has been shown to be epigenetically active as a demethylating agent in a human lymphoma cell line, causing downregulation of DNA methyltransferase 1 (DNMT1) through ubiquitin-targeted degradation. Zebularine (Zeb), a similar cytidine analog, also has demethylating activity as well as oral bioavailability. The hypothesis of the present study was that 6-TG and Zeb would cause downregulation of DNMT1 and globally demethylate the genomic DNA of canine lymphoma cells. The secondary hypothesis was that these agents would cause a dose-dependent decrease in cell proliferation in canine lymphoma cells. Canine CLGL-90 malignant T cells and CLL 17–7 cells were incubated in modified RPMI media. They were treated with 6-TG, Zeb, or control media at biologically relevant concentrations. Following treatment with each agent, DNMT1 protein and global DNA methylation were significantly decreased. A dose-dependent decrease in cell survival was also observed, with apoptosis being the primary mode of cell death in the CLGL-90 cell line. These results confirm the demethylating action of 6-TG and Zeb in canine cells which is similar to that shown in human cell lines. Confirmation of this mechanism supports the clinical application of these compounds as demethylating drugs in veterinary patients.
Effect of Uniform Suction on Laminar Film Condensation on a Porous Vertical Wall

The problem of film condensation on a porous wall has been solved by a boundary layer treatment. A dimensionless suction velocity parameter β, which is proportional to the uniform suction velocity vw and 1/4 th the power of longitudinal coordinate (x1/4 ), is defined to characterize the process. The results are restricted to small values of β, as the solutions are given by power series expansion in β. The effects of uniform suction on heat transfer, condensation rate, film thickness, and velocity and temperature profiles are demonstrated through various examples. In general, uniform suction causes a substantial increase of heat transfer and condensation rate, especially at low subcooling and at high Prandtl numbers. The problem involves three governing parameters: subcooling, Prandtl number, and suction velocity. Comparison with the previous work of Jain and Bankoff is discussed.
Statistics and moments-parameter estimates for a duoprocess paired-associate learning model

Abstract A model postulating all-or-none unlearning of wrong alternatives as well as acquisition of correct alternatives is presented. Moments estimates based on the total error distribution are developed for c , the learning rate constant, and for a , the unlearning rate constant. Statistics for testing the model are presented. They are: mean and variance for total errors, theoretical learning curve, trials until last error, and distribution of responses until the first trial upon which some alternative occurs for the last time.
A plastic operation for congenital absence of vagina

T HERE have been many operative methods used for the construction of a congenital absent vagina and three operative procedures that have been somewhat successful. First, resection of rectum and employment of piece of rectum (Schubert); second, resection of a loop of small bowel (Baldwin) ; third, transplantation of skin flaps and flaps of labia minora (G raves, Frank, Geist, and Davis and Cron; also Marion Douglasse). The operations by Schubert and Baldwin show a high mortality (12.5 to 17.5 per cent). The skin graft and grafts from the labia minora reduce the mortality but are very complicated and the results uncertain. The operation which is herewith presented is quite simple and without any necessary mortality and the end-result is nearest to the normal vagina. This operation was a three-step procedure over a period of three years, but could easily be completed in six or eight months. This being a charity case, the patient desired to enter the hospital only during the writer’s service, which is three months out of each year.
Evolution and organizational information systems: an assessment of Nolan's stage model

Richard Nolan's stage model is the best known and most widely cited model of computing evolution in organizations. The model's development over a decade demonstrates its own evolution from a simple theory, based on the factoring of change states indicated by changes in computing budgets, to an elaborate account of the characteristics of six stages of computing growth. An analysis of the model's logical and empirical structure reveals a number of problems in its formulation that help to account for the fact that its principal tenets have not been independently validated. The model is shown to be an “evolutionistic” theory within the theories of evolution in the social sciences, focusing on assumed directions of growth and an implied end state toward which growth proceeds, and suffering from problems inherent in such theories. Further research based on an “evolutionary” view of computing growth is suggested as a means of improving theories of computing in organizations.
Mechanisms of Coordination in Distributed Neural Circuits: Decoding and Integration of Coordinating Information

We describe the synaptic connections through which information required to coordinate limb movements reaches the modular microcircuits that control individual limbs on different abdominal segments of the crayfish, Pacifastacus leniusculus . In each segmental ganglion, a local commissural interneuron, ComInt 1, integrates information about other limbs and transmits it to one microcircuit. Five types of nonspiking local interneurons are components of each microcircuit's pattern-generating kernel ([Smarandache-Wellmann et al., 2013][1]). We demonstrate here, using paired microelectrode recordings, that the pathway through which information reaches this kernel is an electrical synapse between ComInt 1 and one of these five types, an IRSh interneuron. Using single-electrode voltage clamp, we show that brief changes of ComInt 1's membrane potential affect the timing of its microcircuit's motor output. Changing ComInt 1's membrane potential also changes the phase, duration, and strengths of bursts of spikes in its microcircuit's motor neurons and corresponding changes in its efferent coordinating neurons that project to other ganglia. These effects on coordinating neurons cause changes in the phases of motor output from other microcircuits in those distant ganglia. ComInt 1s function as hub neurons in the intersegmental circuit that synchronizes distributed microcircuits. The synapse between each ComInt 1 and its microcircuit's IRSh neuron completes a five synapse pathway in which analog information is encoded as a digital signal by efference-copy neurons and decoded from digital to analog form by ComInt 1. The synaptic organization of this pathway provides a cellular explanation of this nervous system's key dynamic properties. [1]: #ref-50
An Examination of Campus Climate for LGBTQ Community College Students

This study examines campus climate for lesbian, gay, bisexual, transgender, and queer (LGBTQ) undergraduate students at community colleges. Data for the study originates from Rankin, Blumenfeld, Weber, and Frazer’s (2010) State of Higher Education for LGBT People. We analyzed both quantitative data generated from closed-ended survey questions and qualitative data gleaned from open-ended survey questions. Results suggest that classroom climate plays a large role in determining students’ perceptions of campus climate. Findings also indicate that first-generation LGBTQ students experience a more hostile campus climate. Based on the findings, we offer recommendations for future research and potential best practices for working with LGBTQ community college students.