cssi/SciSciGPT-SciSciNet huggingface dataset:
FPGA-based implementation of a robust IEEE-754 exponential unit

This work explores the feasibility of implementing a floating-point exponentiation unit on reconfigurable computing systems. A table-driven exponentiation unit was implemented using synthesizable VHDL. The project included creating pipelined submodules for implementing basic IEEE-754 single precision operations such as addition, multiplication, and division by 32. These modules were then linked together to form the overall unit. The designs were synthesized, placed and routed. Results indicate that today's FPGAs are well suited for this operation.
An interactive broadcasting protocol for video-on-demand

Broadcasting protocols reduce the cost of video-on-demand services by distributing more efficiently videos that are likely to be simultaneously watched by several viewers. Unfortunately, they do not allow the customer to pause, move fast forward or backward while watching a video. We present an interactive pagoda broadcasting protocol that provides these functions at a very reasonable cost. Our protocol is based on the pagoda broadcasting protocol and requires a set-top box buffer large enough to keep in storage all video data until the customer has watched the entire video. As a result, rewind and pause interactions do not require any server intervention. To minimize the bandwidth requirements of fast forward interactions, the server only transmits the segments that are not available on any of the server broadcasting channels. We evaluate the overhead of these fast forward operations through a probabilistic model. Our data indicate that the most costly fast forward operations are those starting at the beginning of the video and jumping to the beginning of the second half of the video while most fast-forward operation taking place during the second half of the video require little or no additional data.
Opportunities and Constraints of Parallel Computing

As the speed of uniprocessors approaches the theoretical limit, it is clear that parallel processing is the only way to keep increasing the speed of computation. As a matter of fact, since very expensive technology is required to keep increasing the speed of uniprocessors, parallel processing using less expensive technology offers a cost-effective alternative for high-speed computation. A number of commercial parallel machines have appeared on the market, but parallel computing has not taken off, and still remains the purvey of a few researchers in industrial and academic labs. Why? There are a number of reasons. A consideration of them points to potential opportunities and constraints in parallel computing.
Use of Antihypertensive Drugs during Pregnancy and Lactation

The decision to treat elevated arterial pressure in pregnancy depends on the risk and benefits imposed on the mother and the fetus. Treatment for mild-to-moderate hypertension during pregnancy may not reduce maternal or fetal risk. Severe hypertension, on the other hand, should be treated to decrease maternal risk. Methyldopa and beta-adrenoceptor antagonists have been used most extensively. In acute severe hypertension, intravenous labetalol or oral nifedipine are reasonable choices.
Efficient Message-Passing within SMP Systems

Message-passing libraries have made great strides in delivering a high percentage of the performance that the network hardware offers. There has been much less effort focused on improving the communications between processes within an SMP system. SMP nodes are becoming an integral part of many clusters and MPP systems. These SMP nodes are also growing in size, requiring attention to scalable solutions to passing messages through shared-memory segments. The research presented in this paper will focus on an analysis of the performance of existing message-passing libraries, as well as new methods being evaluated using the MP_Lite message-passing library. The NetPIPE utility is used to provide point-to-point measurements that are backed up by tests with a real application.
Crack Initiation, Kinking and Nanoscale Damage in Silica Glass: Multimillion-Atom Molecular Dynamics Simulations

We present molecular dynamics (MD) simulations of crack kinking, growth, propagation and healing at the nanometer scale in a confined, pre-cracked silica glass subjected to dynamic mode II loading. The pre-crack tip kinks towards maximum mode I tension and nanometer scale cavities are nucleated in the tensile region ahead of the kink. Nanocavities coalesce with kinks to form wing cracks. Dynamics of wing cracks are dominated by coalescence with damage cavities, and the growth and healing of crack and cavities are controlled by confinement.
Effect of Oxygenation on Stem-Cell Therapy for Myocardial Infarction

Stem-cell transplantation to treat acute myocardial infarction (MI) is gaining importance as a minimally invasive and potent therapy to replace akinetic scar tissue by viable myocardium. Our recent studies have shown that stem-cell transplantation marginally improvesmyocardial oxygenation in the infarct tissue leading to improvement in cardiac function. The aim of the present study was to determine the effect of hyperbaric oxygen (HBO) treatment on myocardial oxygenation and recovery of function in MI hearts. Fisher-344 rats were subjected to MI by permanently ligating the left-anterior-descending (LAD) coronary artery. The rats were then exposed to 100% O2 at a pressure of 2 atmospheres for 90 minutes, and the exposure was repeated for 5 days a week for 2 weeks. Adult bone-marrow-derived rat mesenchymal stem cells (MSC, 5x105 cells) were mixed with OxySpin (LiNc- BuO, oxygen sensor) and implanted in the infarct and peri-infarct regions of the heart. M-mode ultrasound echocardiography was performed at baseline and at 2 weeks post-transplantation. The myocardial pO2 in theMSC+HBOgroup (16.2±2.2 mmHg) was significantly higher when compared to untreated MI (3.8±1.9 mmHg) or MSC (9.8±2.3 mmHg) groups. In addition, there was a significant improvement in cardiac function, increased vessel density, and VEGF expression in MSC+HBO group compared to MSC group (p < 0.05). In conclusion, the results suggested a beneficial effect of HBO administration on stem-cell therapy for MI.
Strategic options for automotive suppliers in the global market

The automotive industry is undergoing structural change, driven by technological, economic and commercial forces. The objective of this paper is to investigate this change, its causes and effects, and to suggest possible features of the emerging industry and its principal participants. The results of the research are as follows. The number of major suppliers in Europe will reduce from the present 1500 firms to less than 1000, but a more substantial reduction is not indicated in the immediate future. European suppliers are small by world standards (with the exception of Bosch) and may be expected to grow, organically and by acquisition. European suppliers are not performing at world–class levels, either in terms of quality achievement, or technically. Whilst most participants agree that there will be tier structures within the industry, current purchasing policies do not indicate their formation. The principle of assemblers entrusting significant proportions of the vehicle R&D work to the suppliers is not genuinely accepted by many in the assembly industry. Customer–vendor relationships have improved but are still fragile in many instances. The influence of Japanese suppliers in Europe is small at present but is likely to be a major factor in the next stage of the industry's development.
Abnormalities of Renal Function and Circulatory Reflexes in Primary Aldosteronism

The renal response to intravenous administration of isotonic saline solution and circulatory reflex reactivity was studied in nine patients with primary aldosteronism before and after surgical removal of an adrenal adenoma. In preoperative tests, infusion of saline was followed by abnormally rapid renal excretion of sodium and water, such as occurs in patients with autonomic insufficiency. Circulatory reflex function was also abnormal in all patients; the most severe impairment was shown by two patients with hypokalemia and weakness of long duration. Postoperatively, both renal and circulatory reflex responses returned to normal or near normal. In preoperative tests on three patients, potassium repletion effected a similar correction of both renal and circulatory reflex abnormalities. The cause of these abnormalities in patients with primary aldosteronism is not known. Potassium depletion may be a factor, although a general disturbance of autonomic cardiovascular function cannot be excluded.
Adoptive CD8 + T-Cell Immunotherapy of AIDS Patients with Kaposi's Sarcoma

This article reviews published and original findings from two clinical trials of adoptive CD8+ T-cell immunotherapy of patients with acquired immunodeficiency syndrome (AIDS) and Kaposi's sarcoma (KS). In the first trial, AIDS patients with either KS or oral hairy leukoplakia (OHL) received five rounds of reinfusions of 10(8)-10(10) ex vivo expanded and activated autologous CD8+ T cells. Recombinant interleukin-2 (rIL-2) was coadministered only with the fifth and final infusion. Improvement, and in some cases, resolution of OHL, KS, and candidiasis was observed with no side effects. The observation that clinical improvement of KS was more pronounced when reinfusion of CD8+ T cells was followed by rIL-2 infusion led to a second clinical trial designed to examine the effect of repeated infusions of autologous CD8+ T cells with concomitant rIL-2 administration in the treatment of AIDS-related KS. Improvement of KS status was observed in four out of the eight patients studied (three partial and one complete response). The CD8+ T-cell immunotherapy protocol also provided the opportunity to comparatively study CD8+ T-cell-associated genetic programs. Baseline expression patterns of soluble and surface immune markers by CD8+ T cells from AIDS patients and uninfected controls were predominantly of the type 1 type and differed mainly at a quantitative or kinetic level. Deficiencies in immune mediator expression by CD8+ T cells from AIDS patients tended to dissipate with progression through the protocol. Findings are discussed in the context of current knowledge and therapeutic implications of CD8+ T-cell function in AIDS and neoplasia.
Imaging performance of displays: Past, present, and future*

— Some display devices that were tried unsuccessfully in the past are reviewed briefly. Then the display devices that are in use at present are described and their advantages and disadvantages discussed. Properties where improvements are needed include greater consistency between pictures displayed from the same signals on different devices, greater color gamut, less impairment by ambient illumination, and better resolution. Finally, consideration is given to some of the ways in which these needs may be met.
Association between reactive arthritis and antecedent infection with Shigella flexneri carrying a 2-Md plasmid and encoding an HLA-B27 mimetic epitope.

Objective. To determine whether Shigella flexneri strains that cause enteric infection and are associated with reactive arthritis (ReA) carry a 2-Md plasmid, pHS-2, which encodes an HLA–B27 mimetic epitope. Methods. Plasmid DNA from Shigella isolates was characterized by DNA–DNA hybridization, restriction endonuclease digestion, and sequencing. Results. S flexneri strains associated with ReA carried a 2-Md plasmid homologous to pHS-2. Conclusion. The finding of pHS-2 in additional Shigella strains associated with ReA underscores its potential importance in the etiology of the disease.
Length and Complexity of US and International HIV Consent Forms from Federal HIV Network Trials

BACKGROUND Informed consent is required in most clinical research with humans. While federal regulations state consent information should be understandable to participants, concerns have been raised that consent forms are overly long and complex.
Photoelectron spectroscopy of the anions, CH3NH− and (CH3)2N− and the anion complexes, H−(CH3NH2) and (CH3)2N−[(CH3)2NH]

Abstract The photoelectron spectra of the negative ions, CH 3 NH − and (CH 3 ) 2 N − , as well as the anion complexes, H − (CH 3 NH 2 ) and (CH 3 ) 2 N − [(CH 3 ) 2 NH] have been measured. The adiabatic electron affinities of CH 3 NH and (CH 3 ) 2 N were determined to be 0.432±0.015 and 0.504±0.030 eV, respectively. The vertical detachment energies of H − (CH 3 NH 2 ) and (CH 3 ) 2 N − [(CH 3 ) 2 NH] were determined to be 1.157±0.025 and 1.1±0.1 eV, respectively, while the anion–neutral dissociation energies of H − (CH 3 NH 2 ) and (CH 3 ) 2 N − [(CH 3 ) 2 NH] were found to be 0.40 and 0.6 eV, respectively. These species are compared with their unmethylated counterparts, NH 2 − , H − (NH 3 ), and NH 2 − (NH 3 ).
POST-HUMAN ANTHROPOLOGY

This article discusses recent performative ethnographic work in the Goth/Industrial music scene as the band “Blood Jewel”—http://www.myspace.com/bloodjewelband—and how through the medium of cyber space this has led to different kinds of engagements with ethnographic “subjects.” This experience is the context for theorizing the basis and forward trajectory of ethnographic fieldwork, especially with regard to topics such as the study of sexuality and violence which have proved resistant to standard ethnographic strategies. The cultural meanings of sexual and violent representation, challenges to normative sexualities, and the emergence of digital subjectivities and ontologies are then examined in relation to this ethnographic approach. It is concluded that an anthropology still stuck in the problematic of the European Enlightenment must urgently consider the disappearance of its traditional “subjects” as meaningful ethnographic categories of research and work to contribute to the emergence of a post-human a...
Wear of yttria-doped α-alumina: effects of grain-boundary composition and machine stiffness

Abstract The study used four samples of α-alumina, with grain sizes 0.49–1.44 μm, dopant concentrations 0–1500 ppm yttria, and a sintering aid of MgO at a concentration of 500 ppm in all samples. Wear was measured in unlubricated sliding at low velocity under loads of 60–100 N in ambient air. This load range comprises the intermediate wear regime, which is sensitive to grain boundary fatigue and grain pull-out, and the regime of catastrophic wear characterized by macroscopic fracture. The results show that the transition between intermediate and catastrophic wear is determined by machine vibrations. In the intermediate wear regime, the wear rate is higher for material with an yttria grain boundary phase. Yttria promotes adhesion between the sliding surfaces and decreases the grain boundary strength. In this regime, the wear volume increases with a high power of the applied load, in apparent contradiction with the fact that the real contact area is proportional to the load and therefore the local contact stresses are independent of it. The contradiction is lifted by recognizing that the stresses at grain boundaries occur at a sufficient distance below the surface to cause a load dependence of the local stresses.
Stochastic analysis of gang scheduling in parallel and distributed systems

Abstract Gang scheduling is an approach for resource allocation in parallel and distributed systems that combines time-sharing with space-sharing to ensure a short response time for interactive tasks and high overall system throughput. In this paper, we present queueing theoretic models for a particular gang scheduling system under a workload representative of large-scale engineering and scientific computing environments. We derive a detailed mathematical analysis of these models, from which we obtain closed-form expressions for different performance measures of interest. Our model and analysis is then used to analyze several fundamental performance tradeoffs associated with gang scheduling.
Ultrasmall Mode Volumes in Dielectric Optical Microcavities

We theoretically demonstrate a mechanism for reduction of mode volume in high index contrast optical microcavities to below a cubic half wavelength. We show that by using dielectric discontinuities with subwavelength dimensions as a means of local field enhancement, the effective mode volume (V(eff)) becomes wavelength independent. Cavities with V(eff) on the order of 10(-2)(lambda/2n)(-3) can be achieved using such discontinuities, with a corresponding increase in the Purcell factor of nearly 2 orders of magnitude relative to previously demonstrated high index photonic crystal cavities.
Plastic intensity factors for cracked plates subjected to biaxial loading

An elastic-plastic analysis is performed for an infinite plate under plane stress conditions which contains a finite line crack and is subjected to biaxial loading. In the large scale yielding range, the amplitude of the dominant singularity at the crack tip, the plastic stress (or strain) intensity factor, is found to depend on the magnitude of loading parallel to the crack direction. The predicted value for the fracture initiation stress which is based on a plastic intensity factor fracture criterion, increases under lateral, tensile loading. Compressive loading parallel to the crack has the opposite effect on the fracture initiation stress.
Measurement nonlinearity interpreted as material behavior in dynamic nanoindentation

Abstract This paper explores the errors that may arise in when interpreting dynamic nanoindentation measurements with a linear oscillator model. The work was motivated by an experimental observation that the system's primary resonance can be dramatically altered by changes in loading conditions. Investigations elucidate that different sources of nonlinearity can interact to alter the identified contact stiffness which will manifest itself as a change in the system's primary and secondary resonances. The errors associated with interpreting dynamic indentation measurements with a linear model are investigated through modeling, analysis, and numerical study. Theoretical efforts show that measurement nonlinearity can be falsely interpreted as material behavior. Hence, the common practice of applying a linear oscillator model is expected to sometimes lead to significant errors. These finding suggest that a nonlinear analysis may often be required to improve measurement interpretations.
Residential segregation in American cities: Common ground and differences in interpretation

Despite the intensity of the recent debate between Clark and Galster, there is considerable agreement that there are multiple forces which create the patterns of residential separation found in American cities, and that government or public discrimination plays a minor role. The differences between Clark and Galster relate to the relative weight to be given to private discrimination and the role of preferences in explaining the patterns of racial separation. The actual weight to be given to private discrimination is yet to be specified.
Airway Complications After Lung Transplantation

Airway complications after lung transplantation present a formidable challenge to the lung transplant team, ranging from mere unusual images to fatal events. The exact incidence of complications is wide-ranging depending on the type of event, and there is still evolution of a universal characterization of the airway findings. Management is also wide-ranging. Simple observation or simple balloon bronchoplasty is sufficient in many cases, but vigilance following more severe necrosis is required for late development of both anastomotic and nonanastomotic airway strictures. Furthermore, the impact of coexisting infection, rejection, and medical disease associated with high-level immunosuppression further complicates care.
Effect of Heat Treatment and Modification on Conformation and Flavor Binding by β‐Lactoglobulin

The flavor binding behavior of native β-lactoglobuIin (β-Lg) was significantly altered by thermal or chemical modification. Upon heat-treatment at 75°C for 10 and 20 minutes the binding affinity for 2-nonanone was reduced and the number of sites for binding was increased. This was related to conformational changes and aggregation of β-Lg. Reduction of the disulfide bonds and ethylation of carboxylic acid groups also induced conformational changes which reduced the binding affinity of β-Lg for 2-nonanone.
Evaluation of thermospheric models and the precipitation index for satellite drag

Abstract Precision radar tracking data on three spherical satellites have been used to evaluate atmospheric density models: Jacchia 1971 /1/, Jacchia 1977 /2/, Barlier et al 1977 /3/, Hedin 1983/4/, and Hedin 1987 /5/. The satellites have perigee heights (q) of 270 km, 780 km, and 1500 km. The Precipitation Index (PI) quantifies the intensity and spatial extent of high-latitude particle precipitation from observations made by the NOAA/TIROS weather satellites. None of these models now use this index, whereas we have previously shown as much as 0.50 correlation of the density model error and the PI. We will report on extension of our previous work in three ways: 1) The data set has been extended to more than one year; 2) A satellite at 1500 km altitude has been added, and is important since it provides information about the atmosphere at altitudes where little or no data is input into the models; and 3) The recent CIRA87 Model and a thermosphere wind model are evaluated.
Digital spacecraft ionosondes

Abstract In cooperation with RCA, Astro-Electronics Division, a digital spacecraft ionosonde has been developed and its prototype built by ULCAR. On-board use of the Direct Discrete Fourier Transform for signal-to-noise enhancement, suppression of unwanted echoes and the identification of echo properties permit several applications. In ionospheric topside satellites (>800 km above ground) the ionospheric profile over all parts of the earth will be measured with simple and new data compression techniques on board of the satellite. Digital data preprocessing overcomes the breakthrough of ground-based man-made interference and analyzes auroral and equatorial echoes. Because the ionosonde measures amplitude, phase, Doppler, range and polarization of a radio wave simultaneously, it will be a very useful tool for the Waves in Space Plasma program of the NASA Space Shuttle, especially for a mother-daughter configuration. With a synchronized transmitter on the ground, such a Digisonde in a low-flying satellite (100–400 km) can receive signals from ducted radio waves launched into the ionosphere near natural or artificial ionization depletion areas for the study of large distance radiowave propagation.
An efficiency measurement model for a computerized warehousing system

SUMMARY This paper introduces a model for efficient utilization of warehouse personnel in an inventory selection process. A simple mathematical model, based on a time study that can be applied to establishing standards for efficiency measurement of labour in a warehouse setting is presented. The problem of determining a standard to compute performance in an environment with variable workload is solved by using an adjustable standard for each particular assignment. Specifically the proposed model is designed to estimate the time required to complete a picking cycle. Three time components are considered; the lead time, travel time, and non-efficient time. The results of an empirical study are used to set the values of system parameters. The use of a computer system that can generate order lists is essential for an effective application of this methodology. Useful information can be obtained that can aid managers in formulating and implementing incentive plans and for controlling the labour cost which repres...
Haptic mirror therapy glove: aiding the treatment of a paretic limb after a stroke

This paper describes the creation of a proof-of-concept design for an interactive glove that augments the mirror therapy protocol in the treatment of a paretic limb following a stroke. A review is completed of supporting literature that shows the potential of multi-sensory stimulation and augmentation to increase the efficacy of mirror therapy. Building on this background, a glove is designed to allow the user to stimulate the fingertips of their affected hand by tapping the fingers of their unaffected hand, using Force Sensing Resistors to trigger Linear Resonance Actuators on the corresponding fingers. This paper outlines the design considerations and methods used to create the glove, and discusses the potential for further work in the pursuit of a clinical trial.
Mitral annular kinetics in mitral regurgitation

Methods Population: Patients with degenerative mitral regurgitation (n = 35) with normal LV EF pre and 12 months post mitral valve repair. Normal volunteers (n = 51). Image Acquisition: All participants underwent MRI on a 1.5T scanner (GE Healthcare) optimized for cardiac application. An ECG-gated, breath-hold steady state free precision technique was used to obtain 2 chamber and 4 chamber views with 20 phase imaged in each cardiac cycle. Image Analysis: At end diastole (ED) and end systole (ES), anterior and inferior MA landmarks were manually marked on 2 chamber views. Septal, lateral and apex MA landmarks were marked on 4 chamber views. All landmarks were then automatically propagated to the remaining phases using custom software [1] and manually verified. In each phase, the MA was approximated by a flat plane fit to the 4 landmarks. The MA centroid and plane normal was
Effect of nitroglycerin and cerebrospinal fluid drainage on spinal cord perfusion pressure and paraplegia during aortic cross-clamping.

When sodium nitroprusside (SNP) is used to control proximal blood pressure (Px-BP) during cross-clamping (AXC) of the thoracic aorta, it decreases spinal cord perfusion pressure (SCPP) by reducing distal aortic pressure (Ds-BP) and increasing cerebrospinal fluid pressure (CSFP). The decrease cannot be reversed by CSF drainage (CSFD) because such drainage is limited by a reduction in compliance of the spinal canal. Nitroglycerin can also be used to control Px-BP, but its effect on CSF dynamics has not previously been investigated. In the present study we have compared the effects of NTG alone and in combination with CSFD, with SNP and CSFD. Each group (Gp) of six dogs was treated with SNP + CSFD (Gp 1), NTG alone (Gp 2), and NTG + CSFD (Gp 3). Left carotid and right femoral arteries were catheterized to monitor Px-BP and Ds-BP, respectively. CSFP was monitored and CSF was drained through a spinal needle placed in the cisterna cerebellomedullaris. The thoracic aorta was cross-clamped via a left thoracotomy for 60 min. Data were acquired at baseline, during aortic occlusion, and 24 hr after surgery. There were no significant differences in any measurements among the three groups before AXC; after AXC, Px-BP was maintained between 85 and 95 mm Hg in all groups. Ds-BP was significantly lower in Gp 1 than Gp 2 and 3 (7 ± 2 mm Hg vs. 13 ± 3 mm Hg and 17 ± 2 mm Hg, respectively P 0.05). CSFD effectively kept CSFP at zero values in Gp 3 during AXC, but not in Gp 1. SCPP was significantly higher in Gp 3 than in Gp 1 and 2 (17 ± 2 mm Hg vs -3 ± 4 mm Hg and 4 ± 1 mm Hg, respectively, P < 0.05). All animals in Gp 1 and 2 suffered paraplegia, as opposed to none in Gp 3. NTG causes paraplegia by decreasing SCPP. When used in conjunction with CSFD, it controls Px-BP without causing paraplegia. CSFD cannot counteract the negative effects of SNP on SCPP; therefore, SNP contributes to postoperative paraplegia. The effects of NTG on cerebrospinal fluid dynamics are different from those of SNP. We caution surgeons against the use of NTG without CSFD during aortic cross-clamping.
Should vasectomy reversal be performed in men with older female partners

Purpose: An assumption exists that men with older female partners who seek treatment of post-vasectomy infertility should undergo in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI) rather than vasectomy reversal. Although several studies have reviewed ICSI success rates with advancing maternal age, to our knowledge none has compared them to outcomes for vasectomy reversal in men with older partners. Materials and Methods: The records of all patients with ovulating partners older than 37 years who underwent vasectomy reversal from 1994 through 1998 were reviewed. Patients were contacted to establish pregnancy and birth rates. Costs of vasectomy reversal, testicular sperm extraction, IVF and ICSI were obtained from the financial office of our institution. Results: A total of 29 patients underwent vasectomy reversal with a followup of 3 to 59 months (median 25). Median male age was 46 years (range 37 to 67) and median female age was 40 years (range 38 to 48). A total of 5 pregnancies and 4 live births were achieved. In the 23 patients followed for more than 1 year the pregnancy rate was 22% and live birth rate was 17%. Using this 17% birth rate at our $4,850 cost for vasectomy reversal the cost per newborn was $28,530. In comparison, using the 8% birth rate per cycle of ICSI for women older than 36 years at a cost of $8,315 for testicular sperm extraction and 1 cycle of IVF with ICSI, the cost per newborn was estimated at $103,940. Conclusions: Vasectomy reversal appears to be cost-effective to achieve fertility in men with ovulating partners older than 37 years.
Isolation and structure of hypothalamic MSH release-inhibiting hormone

Summary MSH-release inhibiting hormone (MRIH) activity in bovine hypothalamic extracts, concentrated over 11,000-fold by gel filtration on Sephadex, was further purified by thin-layer chromatography. Two MRIH-active peptides were isolated; one showed a high and the other much weaker MRIH activity. The amino acid sequence of the main MRIH-active peptide, as determined by Edman degradation combined with the dansyl method, was shown to be prolyl-leucyl-glycine amide. These findings were confirmed by mass spectra. Synthetic L-Pro-L-Leu-glycine amide and the natural main MRIH-active peptide showed similar biological activities, chromatographic and electrophoretic mobilities, and mass spectral fragmentation patterns. This work indicates that the structure of bovine MRIH is L-Pro-L-Leu-Gly. NH 2 .
The n→π* optical activity of chiral carbonyl compounds predicted to be optically inactive by the octant rule

The “one-electron” model of n→π* optical activity in chiral carbonyl compounds is carried to second-order in perturbation theory and the results are applied to systems which are predicted by the octant rule to yield zero n→π* optical activity. It is shown that second-order contributions to the n→π* rotatory strength lead to sector rules which are qualitatively different from those obtained from first-order contributions. Inclusion of three-way interactions involving the carbonyl chromophore and two different extrachromophoric perturbing groups (or atoms) lead to second-order contributions to the rotatory strength which can account for the n→π* optical activity in chiral carbonyl systems predicted to be optically inactive by the conventional quadrant and octant rules. These results are shown to be in agreement with the conclusions derived by Ruch and Schonhofer from a purely algebraic theory of molecular chirality.
Predictions of electron temperatures in the Mars ionosphere and their effects on electron densities

Observations of peak electron densities in the Mars ionosphere are well fit by a simplistic theory that assumes the electron temperature, Te, at the peak remains constant as solar zenith angle, χ, changes. However, Te ought to vary with both altitude and χ. Here we use an existing numerical model of ionospheric energetics, which includes both vertical and diurnal variations in temperatures, to predict that Te at the ionospheric peak is relatively independent of χ. This model accurately predicts the observed dependence of peak electron density on χ, whereas predictions using Viking-based electron temperatures that are held constant with time do not. A simplified analytic model is developed to interpret these results further. It predicts that the difference between electron and neutral temperatures is proportional to the ratio of electron heating rate to electron production rate and proportional to the square root of solar irradiance.
Recent advancements in the biosynthetic mechanisms for polyketide‐derived mycotoxins

Polyketides (PKs) are a large group of natural products produced by microorganisms and plants. They are biopolymers of acetate and other short carboxylates and are biosynthesized by multifunctional enzymes called polyketide synthases (PKSs). This review discusses the biosynthesis of four toxic PK, aflatoxins, fumonisins, ochratoxins (OTs), and zearalenone. These metabolites are structurally diverse and differ in their mechanisms of toxicity. However, they are all of concern in food safety and agriculture because of their toxic properties and their frequent accumulation in crops used for food and feed. The focus is on the recent advancements in the understanding of the molecular mechanisms for the biosynthesis of these mycotoxins. Several of the mycotoxin PKSs have been genetically and biochemically studied while other PKSs remain to be investigated. Multiple post-PKS modifications are often required for the maturation of the mycotoxins. Many of these modification steps for aflatoxins and fumonisins are well established while the post-PKS modifications for zearalenone and OTs remain to be biochemically characterized. More efforts are needed to completely illustrate the biosynthetic mechanisms for this important group of PKs.
Note on stationary-axisymmetric vacuum spacetimes with inside ellipsoidal symmetry

The author considers stationary-axisymmetric vacuum spacetimes possessing an additional 'inside' symmetry property; namely he assumes that the projected Riemannian 3-space induced by the stationary Killing field can be filled in with a one-parameter congruence of confocal ellipsoids. He presents a family of exact solutions of vacuum Einstein's equations possessing these symmetries, and it is shown that these spacetimes consist of a three-parameter family of solutions which coincide with the subfamily of the Kerr-NUT spacetimes with vanishing electric (and magnetic) charge. Hence, a simple geometrical characterization can be given for this subfamily of algebraically specialized Petrov type D solutions which resulted from the application of completely different spin coefficient techniques.
Chemical synthesis of o‐thiophosphotyrosyl peptides

The synthon for O-thiophosphotyrosine, Fmoc-Tyr[PS(OBzl)2]-OH (1c), was prepared in 63%;, yield from Fmoc-Tyr-OH by first transient protection as the tBuMe2Si-ester and phosphinylation with (BzlO)2PNiPr2/ tetrazole followed by oxidation of P(III) to P(V) vith S8x in CS2. Building block 1cwas incorporated in the Fmoc solid-phase synthesis of two O-thiophosphotyrosine-containing peptides H-Thr-Glu-Pro-Gln-Tyr(PS)-Gln-Pro-Gly-Glu-OH (2) and H-Thr-Arg-Asp-Ile-Tyr(PS)-Glu-Thr-Asp-Phe-Phe-Arg-Lys-OH (3), corresponding to sequences of the p60src (523–531) protein and an insulin receptor (IR) (1142–1153) analogue, respectively. An alternative approach of synthesis, the global phosphorylation of a resin-bound peptide, also proved useful. Thus, the free tyrosyl side-chain containing-peptide IR (1142–1153) on support was phosphinylated with the above phosphoramidite reagent followed by oxidation with either S8/CS2 or tetraethylthiuram disulfide/CH3CN solutions. Deprotection and peptide-resin cleavage was performed with a TFA/thiophenol (H2O) mixture. Crude peptides 2 and 3 were stable to the acidolytic deprotection. Preparative RP(C18)HPLC was initially performed using 0.1% TFA(aq) EtOH solvents. However, analyses of fractions resulting from the purification step indicated significant decomposition of thiophosphopeptide in solution. Stability measurements both as a function of time and pH. further confirmed this initial finding. Purifications performed at intermediate pH using a triethylammonium acetatc (pH 7.5) CH3CN solvent system overcame this problem.
A GATA Transcription Factor Recruits Hda1 in Response to Reduced Tor1 Signaling to Establish a Hyphal Chromatin State in Candida albicans

Candida albicans is an important opportunistic fungal pathogen of immunocompromised individuals. One critical virulence attribute is its morphogenetic plasticity. Hyphal development requires two temporally linked changes in promoter chromatin, which is sequentially regulated by temporarily clearing the transcription inhibitor Nrg1 upon activation of the cAMP/PKA pathway and promoter recruitment of the histone deacetylase Hda1 under reduced Tor1 signaling. Molecular mechanisms for the temporal connection and the link to Tor1 signaling are not clear. Here, through a forward genetic screen, we report the identification of the GATA family transcription factor Brg1 as the factor that recruits Hda1 to promoters of hypha-specific genes during hyphal elongation. BRG1 expression requires both the removal of Nrg1 and a sub-growth inhibitory level of rapamycin; therefore, it is a sensitive readout of Tor1 signaling. Interestingly, promoters of hypha-specific genes are not accessible to Brg1 in yeast cells. Furthermore, ectopic expression of Brg1 cannot induce hyphae, but can sustain hyphal development. Nucleosome mapping of a hypha-specific promoter shows that Nrg1 binding sites are in nucleosome free regions in yeast cells, whereas Brg1 binding sites are occupied by nucleosomes. Nucleosome disassembly during hyphal initiation exposes the binding sites for both regulators. During hyphal elongation, Brg1-mediated Hda1 recruitment causes nucleosome repositioning and occlusion of Nrg1 binding sites. We suggest that nucleosome repositioning is the underlying mechanism for the yeast-hyphal transition. The hypha-specific regulator Ume6 is a key downstream target of Brg1 and functions after Brg1 as a built-in positive feedback regulator of the hyphal transcriptional program to sustain hyphal development. With the levels of Nrg1 and Brg1 dynamically and sensitively controlled by the two major cellular growth pathways, temporal changes in nucleosome positioning during the yeast-to-hypha transition provide a mechanism for signal integration and cell fate specification. This mechanism is likely used broadly in development.
Repeated visual distracter exposure enhances new discrimination learning and sustained attention task performance in rats.

Repeated exposure to distraction requires attentional effort to restore task performance. However, the impact of repeated distracter exposure and exertion of attentional effort on new learning has not been examined. In the present experiment, rats were trained in a two-lever sustained attention task. Rats then continued to train, for 12 sessions, in this task either with or without a flashing houselight distracter throughout the session. The flashing houselight transiently decreased attentional performance. Trials that were part of a new light-location discrimination task were then interspersed within the sustained attention task sessions. The frequency of these new light-location discrimination trials increased with additional training. Rats exposed to the distracter exhibited higher accuracy levels during some blocks of sessions in the new light-location discrimination task trials and in the remaining sustained attention task trials compared to rats that were not exposed to the distracter. The effects of repeated distracter exposure are interpreted in the context of an “occasion-setting” model that has been used to describe performance in this task.
Training Teachers in Evidence-Based Practice for Individuals With Autism Spectrum Disorder: A Review of the Literature

In this review, the authors include 23 studies where researchers experimentally evaluated training for teachers of students with Autism Spectrum Disorder (ASD). Authors summarized qualitative infor...
A multifaceted genetics educational program for nursing faculty

The 1998 Statement on the Scope and Standards of Genetics Clinical Nursing Practice asserts that all nurses should be able to identify, refer, support and care for persons affected by, or at risk for manifesting or transmitting, genetic conditions. Nurses also need to play a significant role in the management of genetic information. However, results from multiple surveys conducted over the past 26 years have repeatedly demonstrated that nurses receive limited genetics education in their basic nursing programs. Nursing faculty's limited educational preparation in genetics is a significant barrier to increasing genetics content in nursing curriculum. The Summer Genetics Program for Nursing Faculty was developed to address the genetics continuing educational needs of nursing faculty. One component of the program was a 12-day Genetics Summer Institute (SI). In 1997. 26 nursing faculty attended the first SI and in 1998, 34 additional nursing faculty attended the second SI. These 60 participants represented 59 nursing schools from 25 states and the District of Columbia. Change in participants genetics knowledge was measured using a 35 item pre / post-test Both participant groups demonstrated statistically significant improvement (p<0.01) in post-test scores. Follow up of 1997 participants has occurred twice since the first SI to assess participants progress toward increasing genetics content in their curricula. Results indicate that 75% used information and educational resources provided during and following the SI in their own and/or fellow faculty's existing lectures. Nearly all discussed the importance of genetics with their school administrators and fellow faculty. Over 80% pursued further genetics continuing education. Seven of the 1997 participants developed a genetics course. Twice yearly follow-up is underway for the 1998 participants and will continue for the 1997 participants. This program was funded by the NHGRI's Ethical. Legal and Social Implications Research Program at NIH.
Fate of endosulfan in rats and toxicological considerations of apolar metabolites

Abstract [ 14 C]Endosulfan, α or β isomers separately, was administered to rats as a single oral dose and as a dietary supplement for 14 days. No appreciable differences were observed in the fate of the two isomers. Five days after the single dose, 75% of the dose had been voided in the feces and 13% in the urine. Of the total radiocarbon consumed in the diet after 14 days, 56% had been eliminated in the feces and 8% in the urine. Bile collection studies showed that up to 47% of a single oral dose was eliminated from the liver via this route; enterohepatic circulation was not apparent. Maximum [ 14 C]endosulfan equivalents in body tissue occurred in the kidney and liver, 3 and 1 ppm, respectively, after 14 days of feeding 5 ppm of endosulfan. Apolar metabolites in the excreta and/or tissues were a minor portion of the total residues and consisted of the sulfate, diol, α-hydroxy ether, lactone, and ether derivatives of endosulfan. The sulfate was slightly more toxic to mice than endosulfan, while the other products were less toxic. Neither endosulfan nor its metabolites were active in the Salmonella mutagenicity test. Endosulfan in the diet of rats for 28 days at 50 ppm did not induce liver oxidase enzymes, alter liver or kidney weights, or influence the rate of weight gain of the animals.
Survey of Internet users’ attitudes toward Internet advertising

Abstract Many have speculated about the current state of Internet advertising (IA), how it compares to advertising in general (GA), and its implications for traditional marketing models and practices. Although many estimates exist regarding who uses the Internet as well as guidelines about how best to design IA, little is known about Internet users’ attitudes toward IA, much less what characterizes these attitudes. To test this, a national sample of over 400 participants with at least some exposure to the Internet was surveyed. The results revealed no majority opinion of IA: approximately a third of respondents liked, disliked, and felt neutrally toward IA, respectively. A regression analysis indicated that enjoyment of looking at Internet advertisements, its informativeness, and its utility for making behavioral (purchasing) decisions contributed to participants’ attitudes toward IA. Enjoyment of looking at IA contributed the most to attitudes toward IA, yet at the same time appears to be one of IA's weakest features. In order to assess whether attitudes toward and perceptions of IA might reflect attitudes toward advertising in general by this demographic group, rather than attitudes toward IA per se, responses were compared to those of a demographically weighted-to-match national sample of over 1,000 who answered similar questions in regard to advertising in general. The results indicate that more respondents found IA to be informative and trustworthy than a demographically similar sample found GA. Even though the attitudes and perceptions of IA and GA were significantly different, the structure of GA and IA attitudes was the same. Implications for the design of IA are discussed.
Recent advances in GaN power electronics

Gallium Nitride power devices are poised to replace silicon-based MOSFETs in power switching applications having weight and volume constraints, while simultaneously needing a high overall efficiency. With its projected 100x performance advantage over silicon, GaN is a game changing technology for energy-efficient power electronics. This paper reviews the advantages of GaN material and devices, the performance of these devices in power circuits, and the potential applications for this technology.
ISI's impact factor as misnomer: a proposed new measure to assess journal impact

The purpose of this communication is to discuss a widely used measure of journal impact that is defined by the Institute of Scientific Information (ISI) and available for thousands of journals in the Journal Citation Reports. The name of the measure is the impact factor. A major issue, addressed in this article, concerns what impact factor really measures. We will argue that ISI's impact factor is misnamed and misused, and will suggest an alternative name and interpretation of the measure. We will also suggest a new measure to assess the impact of a given journal using citations.
Imaging data in autism: From structure to malfunction

During the last two decades, neuroimaging studies have improved our knowledge of brain development and contributed to our understanding of disorders involving the developing brain. Differences in cerebral anatomy have been determined in autism spectrum disorder (ASD). Morphological studies by magnetic resonance imaging have provided evidence of structural differences in ASD compared with the normal population. This has enhanced our view of autism as a neurobiological disorder corresponding with different stages and events in brain development. Alterations in volume of the total brain and specifically the cerebellum, frontal lobe, and limbic system have been identified. There appears to be a pattern of increased and then decreased rate of brain growth over time. We integrate these observations with neurobehavioral findings to provide a developmental hypothesis of the pathophysiology of autism.