cssi/SciSciGPT-SciSciNet huggingface dataset:
Determination of the mutations responsible for the lesch-nyhan syndrome in 17 subjects

Abstract Hypoxanthine — guanine phosphoribosyltransferase (HPRT) is a purine salvage enzyme that catalyzes the conversion of hypoxanthine to inosine monophosphate and guanine to guanosine monophosphate. Previous studies of mutant HPRT proteins analyzed at the molecular level have shown a significant heterogeneity. This investigation further verifies this heterogeneity and identifies insertions, deletions, and point mutations. The direct sequencing of the polymerase chain reaction-amplified product of reverse-transcribed HPRT mRNA enabled the rapid identification of the mutations found in 17 previously uncharacterized cell lines derived from patients with the Lesch-Nyhan syndrome.
A feasibility study of salivary gland autograft transplantation for xerostomia.

Background Radiation-induced xerostomia is a frequent sequela in patients treated for cancer of the head and neck. One strategy to treat xerostomia would be to relocate portions of salivary tissue to adjacent submucosal sites that lie outside the radiation portals such as the anterior oral vestibule. It is not known whether salivary tissue transplanted as an autogenous free graft can survive, function adequately, and not produce mucoceles. Methods Salivary gland tissue from the parotid and submandibular glands of the Syrian hamster were transplanted into the submucosal layer of the cheek pouch. After 3 months of observation, looking at graft size, graft extrusion, ulceration, infection, and mucocele formation, the graft sites were harvested. The specimens then underwent pathologic analysis by hematoxylin and eosin staining, as well as immunohistochemical methods to determine positivity for cytokeratin, smooth muscle actin (SMA), and amylase. Results Histologic analysis of tissue harvested from Syrian hamsters grafted into the cheek pouch demonstrated intact, viable, organized salivary gland tissue. Eighty percent of the animals in the submandibular group and 63% of the animals in the parotid group had at least 1 graft with viable salivary tissue without undue complications. Conclusions Salivary gland tissue can be transplanted successfully as free autogenous grafts in the Syrian hamster model. Further studies are needed to determine whether the grafts will subsequently become functional and whether growth can be biologically stimulated. This approach may be a useful strategy to protect salivary gland tissue in patients undergoing radiotherapy for head and neck cancer.
Properties of impurity-bearing ferrihydrite III. Effects of Si on the structure of 2-line ferrihydrite

Abstract Siliceous ferrihydrites are abundant nanoparticles in natural environments. Although it is well known that the physical properties of ferrihydrite are affected when formed in the presence of silicate oxoanions (SiO44−), the structure of siliceous ferrihydrites (SiFh), and the speciation of Si within these nanosolids are not well understood. In this study we evaluate the effects of Si (at concentrations ranging from 5 to 40 mol% Si) on synthetic ferrihydrite precipitates using structural data derived from synchrotron-based high energy X-ray scattering and pair distribution function (PDF) analysis, in combination with X-ray absorption near edge structure (XANES) spectroscopy, and transmission electron microscopy (TEM). Silicate oxoanions have a major effect on Fe(O,OH)x polyhedral polymerization and ferrihydrite particle growth, illustrated by the formation of smaller, poorly crystalline, structurally disordered/strained ferrihydrite nanocrystallites. Variation in Fh unit-cell parameters is suggested to arise from substantial particle size-induced structural disorder. As a result of this significant size-dependent structural disorder, it was not possible to identify evidence for Si4+ for Fe3+ substitution in these samples based on unit cell parameter variations or refinement of different structural models. Principal component analyses (PCA) and linear combination fits carried out on the PDFs suggest that iron partitions between several phases (e.g., ferrihydrite and an Fe-bearing amorphous silica phase (Amorph. SiO2 + Fe)) in these co-precipitates. A mechanism of co-precipitation is proposed, in which silicate binds to Fe polymers and Fh particles, thus inhibiting particle growth at low Si content. At higher Si content, SiO44− polymerization traps significant Fe, and we suggest that the occurrence of this second Fe pool limits further the availability of Fe required for ferrihydrite particle development. Such Si-ferrihydrite co-precipitates are expected to be more stable in natural environments with respect to reductive dissolution or transformation, and to impact the bioavailability of Fe(III).
Effect of high dose aspirin on coronary hemodynamics during pacing-induced myocardial ischemia.

The effects of aspirin on coronary hemodynamics and transcardiac concentrations of thromboxane B 2 (the stable metabolite of thromboxane A 2 ) were determined at rest and during pacing-induced myocardial ischemia in 11 patients with coronary disease. Control coronary sinus pacing increased both arterial thromboxane B 2 (331 ± 70 to 623 ± 132 pg/ml, p 2 (184 ± 3 to 403 ± 156 pg/ml, p 2 production was demonstrated and circulating thromboxane B 2 was undetectable at rest and during pacing in all patients. Despite these changes in thromboxane B 2 concentrations, coronary blood flow was unchanged by aspirin at rest (107 ± 14 versus 112 ± 13 ml/min, p = NS) and during pacing (189 ± 29 versus 181 ± 25 ml/min, p = NS). Myocardial lactate extraction was also unchanged at rest (24 ± 7 versus 19 ± 5%, p = NS) and during pacing (5 ± 6 versus 9 ± 5%, p = NS). No change occurred in the anginal threshold. Thus, aspirin does not have the vasoconstrictive properties that have been reported with another cyclooxygenase inhibitor, indomethacin. These findings also suggest that thromboxane A 2 production does not play a major role in the pathogenesis of stress-induced ischemia. Nonetheless, intracoronary thromboxane Az production in some patients may potentiate platelet activation and coronary thrombosis. Such patients may benefit from long-term aspirin therapy and can be treated with aspirin without risk of adverse coronary hemodynamic effects.
Nutritional support in acute renal failure

Purpose of reviewAcute renal failure is commonly present in patients with sepsis, shock, trauma, burn injury, or multi-organ dysfunction syndrome. Acute renal failure is an independent risk factor contributing to increased hospital mortality. The major complications associated with acute renal failu
Miscible polybenzimidazole blends with a benzophenone‐based polyimide

Miscible blends of the aromatic polybenzimidazole, poly(2,2(m-phenylene)-5,5′-benzimidazole) (PBI), and the aromatic polyimide formed from 3,3′,4,4′-benzophenone tetracarboxylic dianhydride and 3,3′-diaminobenzophenone (LaRC TPI) have been prepared. Blends with PBI were prepared in N,N-dimethylacetamide solution starting with either the polyamic acid or a 95% imidized form of LaRC TPI; the blend was then precipitated into water or cast as films. The mixture was then imidized thermally to obtain PBI/LaRC TPI blends. Evidence for miscibility was obtained in the form of single composition dependent Tg's intermediate between those of the component polymers and single tan δ dynamic mechanical relaxation peaks. The IR spectra displayed shifts in the NH stretching band, thereby providing evidence for specific interactions related to the miscibility of these two polymers.
The Effect of Taxes and Insurance Costs On Automobile Registrations in the United States

We investigate the determinants of United States automobile registrations in states in 1986, focusing on state and local taxes and fees, and on auto insurance premiums. Using data on state tax and fee structures and the results of a phone survey of states where automobiles are subject to property taxes, we calculate tax and fee costs for a "new" and an "old" car. Regression results show that new car taxes have httle effect on registrations, probably because owners respond to higher taxes by buying older, cheaper cars. Higher old car taxes reduce registrations because low-income owners cannot buy older or cheaper cars and thereby abandon ownership. Insurance premiums appear to have a negative effect on registrations.
Luteinizing hormone-secreting pituitary tumor: biosynthetic characterization and clinical studies

Although gonadotropin-secreting pituitary adenomas are increasingly recognized, tumors secreting only LH are rare. Since gonadotropin production by pituitary adenomas may reflect imbalanced glycoprotein biosynthesis, we studied tumor LH and subunit biosynthesis and secretion in a patient with a LH- and alpha-subunit-producing pituitary tumor. Northern blot analysis of RNA from the tumor revealed the presence of mRNAs encoding both alpha- and beta-subunits of LH with a marked excess of the mRNA encoding LH beta. Analysis of tumor extracts by gel filtration chromatography confirmed an excess of free LH beta relative to free alpha-subunit. Clinical studies demonstrated that the secretion of LH and alpha-subunit by the tumor increased in response to the acute administration of LHRH (100 micrograms, iv) and decreased during a 4-h dopamine infusion (4 micrograms/kg X min). During a 4-week course of LHRH analog (D-Trp6-Pro9-NEt-LHRH) administration, given as a daily sc dose (8 micrograms/kg X day), serum LH and alpha-subunit concentrations increased 7- and 3-fold, respectively, consistent with a chronic agonist effect. Chronic administration of bromocriptine resulted in reduction of serum LH and alpha-subunit levels to normal.
Dimers and trimers of formamidine and its mono-halogenated analogues HNCHNHX, (X = H, Cl, Br, or I): A comparative study of resonance-assisted hydrogen and halogen bonds

Abstract The MP2 ab initio method, and the M052X and the B3LYP density functional theory methods were used to investigate the geometries and energetics of dimers and trimers of formamidine and its mono-halogenated analogues. The primary purpose of this study is to examine the strength of the resonance-assisted N X⋯N interactions for X = H (hydrogen bond), relative to that for X = Cl, Br, or I (halogen bond). It is found that, for the dimers and trimers studied here, the hydrogen bond interaction is stronger than the halogen bond interactions when the halogen is either Cl or Br. For dimers, the N H⋯N interaction is actually of comparable strength to that of the N I⋯N interaction. For example, at the MP2 level the N H⋯N interaction energy is −7.47 kcal/mol, and the corresponding N I⋯N interaction energy is found to be −7.13 kcal/mol. Trimerization produces a small decrease in the hydrogen bond strength, with a hydrogen bond energy of −6.90 kcal/mol at the MP2 level. The opposite is true for the halogen bonds which actually get stronger upon trimer formation, not all to the same extent though. At the MP2 level, for instance, the magnitudes of the interaction energies increase by factors of 1.28 and 1.98 for N Cl⋯N and N Br⋯N respectively. A much more substantial increase factor of 3.36 is found in the N I⋯N interaction energy upon trimer formation. The strengthening of the N I⋯N interaction is so dramatic that the iodine is found midway between the two nitrogen atoms, and the interaction in the trimer is better described as a symmetric N⋯I⋯N interaction.
Team Teaching in the Online Graduate Environment: Collaborative Instruction

Team teaching has long been thought to have positive benefits for learners and teachers in a variety of educational settings. Using an action research model the authors describe the outcomes of team teaching an online graduate level disaster research and statistics course. Separated geographically, two online instructors taught at a distance over the course of five semesters using an interactive team teaching model that allowed for greater interaction and instructor presence. Data was reviewed from instructor reflective logs and student responses to the team teaching model. Results of the study indicate that there was a positive benefit in developing synergy in content and pedagogies, continued instructor learning and continuous reflection on instructional design. Students also reported greater instructor presence and a greater understanding of the research and statistical process through immediacy of feedback and the added access and clarity that resulted from the team teaching process. The use of an interactive team teaching model provides greater clarity and interaction with students and should be considered as an online pedagogical opportunity.
Computer Privacy in America: Conflicting Practices and Policy Choices

American history and custom are rich with the sense of personal privacy. That sense of privacy remained so strong that when the computer became reality in daily government operations, concerns about preserving privacy were vigorously expressed. The Congressional hearings on the National Data Bank(NDB) proposal of the 1960s is illustrative. In the end, the proposal was not funded out of concern for the massive volume of personal data to be contained, transmission of it around the country in telecommunications networks not secure, a national ID system that might emerge, and computer matching schemes to follow. Today, our computer practices sometimes violate those earlier tenets on computers and privacy. Some government networks now contain more personal data than waa proposed for the NDB; networks are not secure, even subject to penetration by hackers; a national ID system has been proposed, but SSN ia one in effect; matching schemes for draft registration verification and debt collection by the Internal Revenue Service on behalf of other agencies, do work. Computer practices in conflict with privacy principles raise the spectre of extra-Constitutional government in America, and leave us with crucial policy choices in computing.
Renal citrate metabolism and urinary citrate excretion in the infant rat

Renal citrate metabolism and urinary citrate excretion in the infant rat. Background Although hypercalciuria has the same prevalence in children as adults, children rarely develop renal stones. This may be explained by a greater urinary citrate excretion in infants compared with adults. The present study examines the renal excretion of citrate and renal cortical citrate metabolism in infant and adult rats. Methods Adult male and newly weaned infant rats were acclimated to metabolic cages and fed synthetic diets. Urine was collected after two days, and renal cortical citrate metabolism was assayed. Results Infant rats had a lower plasma [HCO 3 - ] and higher plasma [K + ] and had a fourfold higher urinary citrate:creatinine ratio and a twofold higher concentration of citrate in their urine compared with adult rats. This higher urinary citrate excretion was not due to a difference in renal proximal tubular Na/citrate cotransporter activity, nor renal cortical citrate synthase or ATP citrate lyase activities in infants as compared with adults. However, infant rat kidneys had significantly lower mitochondrial aconitase (m-aconitase) activity. Renal cortical citrate concentrations were comparable in infant and adult rats. Manipulation of plasma [K + ] to adult levels did not affect the higher urinary citrate excretion in infant rats. Conclusions Urinary citrate excretion in infant rats is greater than in adults but does not parallel tissue [citrate]. Thus, this higher urinary citrate is likely due to maturational differences in the proximal tubule, other than Na/citrate cotransport, that directly affect citrate transport.
Simulation and design of microsystems: a 10-year perspective

10 years ago, the concept of special CAD systems for microsensors and microactuators was proposed at Transducers '87. We now look back over this 10-year period, and examine major trends and accomplishments. Modeling at the system level has grown dramatically, and major advances have been made in the design and simulation of electrostatic actuators and in coupled fluid/structure modeling. Of the many challenges that remain, two appear most significant. The first is the critical step of connecting the behavior of the continuum, as expressed in highly meshed simulations, to equivalent lumped models that can be used efficiently for system-level design and modeling. The second is the incorporation of non-steady-state dissipative behavior into this modeling environment, without having to make unacceptably inaccurate simplifications.
Aqueous high-temperature and high-pressure organic geochemistry of hydrothermal vent systems

Hydrothermal systems associated with oceanic spreading centers are now recognized as relatively common phenomena, and the organic chemical alterations occurring there are rapid and efficient. In the marine hydrothermal systems at water depths > 1.5 km, the conditions driving chemical reactions are high temperatures (up to >400 degrees C), confining pressures (>150 bar), and other parameters such as pH, Eh, and mineralogy in an aqueous open flow medium. Continental hydrothermal systems may also be of interest, as, for example, in failed or dormant rifts and regions around piercement volcanoes. Organic matter alteration by reductive reactions to petroleum hydrocarbons occurs in hydrothermal systems over a wide temperature window (approximately 60 to >400 degrees C), under elevated pressure, and in a brief geological time (years to hundreds of years). The products are rapidly moved as bulk phase or in fluids from the regions at higher temperatures to areas at lower temperatures, where the high molecular weight material separates from the bulk. These conditions are conducive to organic chemistry which yields concurrent products by primarily reduction (due to mineral buffering), oxidation (high thermal stress), and synthesis reactions. This chemistry is just beginning to be elucidated by the geochemical community, but there are various industrial applications which provide useful preliminary insight. Therefore, the behavior of organic matter (inclusive of methane to high molecular weight compounds > C40) in warm to supercritical water needs to be characterized to understand the implications of this novel phenomenon in geological and geochemical processes, and the chemistry occurring over the full temperature spectrum of hydrothermal systems is of relevance to origins of life research.
Laser processes for repair of thin-film wiring

Lasers are being used for a wide range of applications in the microelectronics and packaging industries in such diverse applications as etching, film deposition, repair of open circuits and short circuits, machining and trimming of components, and heating of solder connections. In these applications, the laser radiation is primarily used as a heat source, to melt, ablate, or otherwise alter a material through a thermal process. The use of a laser under these conditions can often lead to damage to the surrounding layers or underlayers, which is particularly important when the laser is not well controlled and when the surrounding layers are thermally sensitive. The development of high-performance wiring for greater wiring density and smaller signal propagation delays has placed greater emphasis on the control of laser-initiated thermal processes. The thin film metal patterns produced in IBM's packaging programs can be used in a wide variety of metal/insulator structures. Although the metallurgies are typically copper based, the choice of insulator materials can vary, with structures produced with both inorganic (glasses and ceramics) and organic (polymers) dielectrics. Several laser-based technologies have been developed at IBM, establishing the capability to modify fine line circuit patterns on the range of packaging materials. These modification techniques, either to repair defects created during the manufacturing process or to restructure the circuit for design and performance reasons, can be achieved with the proper control of the laser conditions. This ability to control the laser/material interaction, with the goal of successfully modifying the circuit without adversely affecting the integrity of the dielectric will be discussed. The applications of these techniques to IBM's thin film packaging will be described, with specific focus on the two technologies recently introduced for the manufacture of East Fishkill's new high end packaging products.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Intel nehalem processor core made FPGA synthesizable

We present an FPGA-synthesizable version of the Intel Atom processor core, synthesized to a Virtex-5 based FPGA emulation system. To make the production Atom design in SystemVerilog synthesizable through industry standard EDA tool flow, we transformed and mapped latches in the design, converted clock gating, and replaced nonsynthesizable constructs with FPGA-synthesizable counterparts. Additionally, as the target FPGA emulator is hosted on a PC platform with the Pentium-based CPU socket that supports a significantly different front side bus (FSB) protocol from that of the Atom processor, we replaced the existing bus control logic in the Atom core with an alternate FSB protocol to communicate with the rest of the PC platform. With these efforts, we succeeded in synthesizing the entire Atom processor core to fit within a single Virtex-5 LX330 FPGA. The synthesizable Atom core runs at 50Mhz on the Pentium PC motherboard with fully functional I/O peripherals. It is capable of booting off-the-shelf MS-DOS, Windows XP and Linux operating systems, and executing standard x86 workloads.
The role of environmental mercury, lead and pesticide exposure in development of amyotrophic lateral sclerosis.

Abstract Exposure to an environmental toxicant as a risk factor in the development of amyotrophic lateral sclerosis (ALS) was first hinted at (demonstrated) in the Chamorro indigenous people of Guam. During the 1950s and 1960s these indigenous people presented an extremely high incidence of ALS which was presumed to be associated with the consumption of flying fox and cycad seeds. No other strong association between ALS and environmental toxicants has since been reported, although circumstantial epidemiological evidence has implicated exposure to heavy metals such as lead and mercury, industrial solvents and pesticides especially organophosphates and certain occupations such as playing professional soccer. Given that only ∼10% of all ALS diagnosis have a genetic basis, a gene–environmental interaction provides a plausible explanation for the other 90% of cases. This mini-review provides an overview of our current knowledge of environmental etiologies of ALS with emphasis on the effects of mercury, lead and pesticides as potential risk factors in developing ALS. Epidemiologic and experimental evidence from animal models investigating the possible association between exposure to environmental toxicant and ALS disease has proven inconclusive. Nonetheless, there are indications that there may be causal links, and a need for more research.
How many adolescents start smoking each day in the United States

Abstract Purpose: To provide daily estimates of first experimentation and attainment of established smoking in adolescents 11–17 years of age. Methods: The 1989 and 1993 Teenage Attitudes and Practices Surveys (TAPS) (16,954 observations) was used to estimate rates in 1991 for: (a) first experimentation (even a few puffs), and (b) established smoking (reaching a lifetime level of at least 100 cigarettes). The 1992 and 1993 Current Population Surveys (CPS) (82,279 adults) allowed calculation of year-specific initiation rates (1980–1989) from the age respondents reported as having started smoking "fairly regularly." Rates were applied to Census data for the appropriate years to yield numbers accruing each day. Estimates were calculated for adolescents (11- to 17-year-olds) and youth (11- to 20-year-olds). Results: For TAPS, in 1991, 4824 adolescents first tried cigarettes and 1975 became established smokers each day. Considering all youth, these estimates increase to 5497/day for first experimentation and to 2933/day for established smokers. For CPS, from 1980 to 1989, around 2300 adolescents initiated fairly regular smoking each day. For all youth, the estimate has increased to about 3400/day. Conclusions: Because approximately 4800 adolescents and 5500 youth appear to be experimenting with cigarettes for the first time each day, and close to 3000 youth become established smokers daily, increased prevention efforts are clearly justified.
Variability in coronary hemodynamics in response to ergonovine in patients with normal coronary arteries and atypical chest pain

Because an increase in coronary vascular resistance in response to ergonovine maleate has been suggested as a possible diagnostic aid for variant angina, changes were evaluated in coronary hemodynamics and serial myocardial thallium-201 perfusion scans in 15 patients without angina and with normal coronary arteries in response to ergonovine (0.05, 0.10 and 0.20 mg intravenously). For the group, heart rate-blood pressure product increased significantly (p
Long-Term Retention of Implanted Transmitters in Colorado Squawfish and Razorback Sucker

Abstract Retention time and effects of surgically implanted radiotransmitters on growth and survival were evaluated for Colorado squawfish Ptychocheilus lucius and razorback sucker Xyrauchen texanus from the Green River, Utah. No transmitter expulsion was detected during radiotracking of 97 Colorado squawfish and 9 razorback suckers that had been implanted between 1978 and 1985. Of 14 transmitters removed from recaptured fish, 12 had been retained from 3 months to 8 years in Colorado squawfish and 2 had been retained for 1 year in razorback suckers. This suggests surgical implants may be retained for the life of the fish. Growth rates of implanted fish did not differ from those of nonimplanted fish of the same size range. There was no difference in mortality between implanted and dangler-tagged fish. Beeswax provided a suitable coating for the surgical implants.
Consenting for Molecular Diagnostics

The growing use of molecular diagnostics poses a wide range of issues and questions concerning informed consent that researchers, health care providers, and others will increasingly need to address. Molecular diagnostics are advancing more rapidly than our ability to decide how best to respond to their complex medical, ethical, legal, psychological, and social implications. Although some of these issues resemble those posed by prior tests, the newness and ever-faster spread of these tests, the advent of large-scale electronic databases, and the many inherent uncertainties involved present new challenges and dilemmas that require careful attention to determine how best to proceed. Obtaining appropriate informed consent will require considerable resources, which many researchers and providers may not fully appreciate. For example, for whole genome sequencing (WGS)2 and whole exome sequencing (WES), most researchers have indicated that they were willing to spend 30 minutes or less on obtaining informed consent (1). Yet the complexity of the information involved will probably often require significantly longer interactions. As articulated in the 1946 Nuremberg Code (2), informed consent is crucial in research because it ensures that investigators respect and protect the autonomy and rights of patients and research study participants. The Declaration of Helsinki (1964; amended in 2013) and the Belmont Report (1979) extended, emphasized, and elaborated on the importance of informed consent in all of health care (3, 4). Patients and participants must ordinarily be appropriately informed about any procedures they are undergoing related to diagnosis, treatment, or research and must consent to these procedures. Subjects should not just sign a form, but understand the content, including the purpose, risks and benefits, alternative options, if any, and plans for confidentiality (5). Yet challenges arise. Consent forms often end up being too long and complicated for many participants to understand. Although most universities …
A Mass Redistribution Algorithm for Right Censored and Left Truncated Time to Event Data

Abstract Failure times are often right censored and left truncated. In this paper we give a mass redistribution algorithm for right-censored and/or left-truncated failure time data. We show that this algorithm yields the Kaplan–Meier estimator of the survival probability. One application of this algorithm in modeling the subdistribution hazard for competing risks data is studied. We give a product-limit estimator of the cumulative incidence function via modeling the subdistribution hazard. We show by induction that this product-limit estimator is identical to the left-truncated version of Aalen–Johansen [1978. An empirical transition matrix for nonhomogeneous Markov chains based on censored observations. Scandinavian Journal of Statistics 5, 141–150] estimator for the cumulative incidence function.
Liquid chromatographic determination of 6-thiopurine metabolites formed in vitro in electrochemical and enzymatic oxidative activation

Abstract A micellar liquid chromatographic method is described which was developed for the separation of the oxidation metabolites of 6-thiopurine formed in vitro by electrochemical and enzymatic activation. Electrochemical activation was carried out with an electrochemical cell on-line with the chromatograph. In the potential range 0.4–0.8 V vs. Pd, intermediate purine-6-sulfenic acid could be detected together with purine-6-sulfinic acid and 6-thiopurine disulfide. At potentials > 0.8 V, purine-6-sulfonic acid was detected and the oxidation of 6-thiopurine was completed. Intermediates and products formed in the horseradish peroxidase-catalyzed oxidation of 6-thiopurine were also studied. Enzymatic activation with horseradish peroxidase was similar to electrochemical oxidation at
A DYNAMIC SCHEDULING COMMUNICATION PROTOCOL AND ITS ANALYSIS FOR HYPERCUBE NETWORKS

We propose a new protocol for one-to-one communication in multiprocessor networks, which we call the Dynamic Scheduling Communication (or DSC) protocol. In the DSC protocol, the capacity of a link is partitioned into two channels: a data channel, used to transmit packets, and a control channel used to make reservations. We initially describe the DSC protocol and the data structures needed to implement it for a general network topology. We then analyze the steady-state throughput of the DSC protocol for random node-to-node communication in a hypercube topology. The analytical results obtained are in very close agreement with corresponding simulation results. For the hypercube topology, and under the same set of assumptions on the node architecture and the routing algorithm used, the DSC protocol is found to achieve higher throughput than packet switching, provided that the size of the network is sufficiently large. We also investigate the relationship between the achievable throughput and the fraction of network capacity dedicated to the control channel, and present a method to select this fraction so as to optimize throughput.
Electrophysiologic effects of bretylium tosylate on the canine heart during coronary artery occlusion and reperfusion.

The electrophysiologic and antiarrhythmic actions of bretylium tosylate were studied after acute coronary artery occlusion and reperfusion in pentobarbital-anesthetized dogs. Three groups of animals were studied: Group I (n = 8) served as saline controls, Group II (n = 7) received bretylium tosylate (10 mg/kg i.v.) 60 min prior to coronary artery occlusion, and Group III (n = 5) received bretylium tosylate (30 mg/kg i.v.) in three divided doses over the 24 h prior to coronary artery occlusion. In Groups II and III the effective refractory period of the nonischemic myocardium was not altered by bretylium before or during the occlusion period, nor was it influenced by bretylium during the subsequent reperfusion period. In Group I the effective refractory period of the ischemic myocardium decreased 24 +/- 3.0% after coronary occlusion and increased 12 +/- 3% above the preocclusion level on reperfusion. In Group II the effective refractory period of the ischemic myocardium decreased 28 +/- 3.2% after coronary occlusion but did not overshoot preischemic levels on reperfusion. In Group III the effective refractory period decreased 15 +/- 3.8% following coronary occlusion and did not overshoot preocclusion levels during reperfusion. The ventricular activation times of the normal and ischemic myocardium were not affected by bretylium tosylate during occlusion or reperfusion in Group II or III. Significant reperfusion arrhythmias were observed only in Groups I and II. These data suggest that bretylium tosylate exerts its antiarrhythmic actions in ischemic myocardium by reducing the dispersion of cardiac refractoriness produced by coronary artery occlusion and, consequently, abolishing the abrupt change in cardiac refractoriness that follows coronary artery reperfusion. These antiarrhythmic actions of bretylium are pronounced in the chronically treated group, suggesting an electrophysiologic basis of the delayed antiarrhythmic actions of bretylium.
Preferred adjective ordering in very young children

Two groups of very young children were given the task of imitating sentences containing multiple prenominal adjectives. The adjectives were presented in preferred and nonpreferred orders. No differences in imitation were found between orders of adjective presentations. Younger children made fewer errors than older children on this task. Both groups exhibited order preferences in a production task which did not correspond exactly to those of older children and adults.
Reliability and Characterization of Micro-Packages in a Wafer Level Au-Si Eutectic Vacuum Bonding Process

A Au-Si eutectic vacuum packaging process was evaluated using high sensitivity poly-Si Pirani vacuum sensors. Encapsulation of devices was achieved by bonding a silicon cap wafer to a device wafer using a Au-Si eutectic solder at above 390°C in a vacuum bonder. The Au-Si eutectic solder encircled the devices, providing an airtight seal. The Pirani gauges were encapsulated and tested over a period of several months in order to determine base pressures and leak/outgassing rates of the micro-cavities. Packaged devices without getters showed initial pressures from 2 to 12 Torr with initial leak/outgassing rates of −0.073 to 80 Torr/year. Using getters, pressures as low as 5 mTorr have been achieved with leak/outgassing rates of <10 mTorr/year. Trends in pressure over time seem to indicate outgassing (desorption of atoms from inside of the microcavity) as the primary mechanism for pressure change over time.Copyright © 2005 by ASME
Comparative‐Effectiveness Research in Distributed Health Data Networks

Comparative-effectiveness research (CER) can be conducted within a distributed health data network. Such networks allow secure access to separate data sets from different data partners and overcome many practical obstacles related to patient privacy, data security, and proprietary concerns. A scalable network architecture supports a wide range of CER activities and meets the data infrastructure needs envisioned by the Federal Coordinating Council for Comparative Effectiveness Research.
Negative Cases in the Nexus Between Self-Control, Social Bonds, and Delinquency

Gottfredson and Hirschi view social bonds and crime as spurious correlates that are associated largely because each results from self-control. Prior tests undermine this hypothesis, pointing to negative cases that run counter to its logic. The authors examine this issue with attention to negative cases in which self-control does not translate into the expected level of social bonding. Analyzing data from a sample of U.S. adolescents, the authors found that negative cases constitute between 8% and 27% of cases and that assessing them sheds new light on the interconnections between self-control, social bonds, and delinquency.
An Invasive Plant Paradox

Why some plants attain extremely high densities in communities where they are exotic, yet remain at low densities in their native ranges is a mystery. The pattern has been called a “paradox” because it conflicts with long-held ideas about the importance of local adaptation for the ecological performance of organisms ( 1 ). This biogeographical shift may be connected to other apparent ecological paradoxes that occur with plant invasions involving processes mediated by soil microbes. Invasions can decrease plant species diversity but also increase plant productivity. Rather than depleting soil resources as productivity increases, invasions often increase soil stocks, pools, and fluxes of nitrogen through processes regulated by microbial communities.
THE GALATIA, KANSAS, CHONDRITE

The paper describes the Galatia meteorite found August 1971 approximately 7 km ENE of Galatia, Barton County, Kansas (98 deg 53 min W, 38 deg 39.5 min N). The single stone weighed 23.9 kg and is partially weathered. Olivine (Fa 24.9) and pyroxene (Fs 20.9) compositions indicate L-group classification, and textural observations indicate that the stone is of petrologic type 6. While Galatia is similar in many respects to the Otis L6 chondrite found 20 miles to the west, Galatia does not have the brecciated structure of Otis and is therefore not part of the same fall.
Mitochondrial nitric oxide synthase

Abstract Nitric oxide (NO ) can bind to and inhibit the terminal enzyme of the mitochondrial respiratory chain, cytochrome c oxidase (complex IV). In vivo, NO is made by the NO synthase (NOS) family of enzymes, and considerable debate has recently arisen regarding a NOS inside mitochondria (termed ‘mtNOS’). Such an enzyme is an intriguing proposition, since it affords unique organelle-based regulatory mechanisms for NO synthesis, and has considerable implications for mitochondrial function. This review serves to discuss some of the current issues regarding mtNOS, such as its isoform identity, the availability of co-factors and substrates within the organelle, and potential physiological vs. pathological roles for the enzyme, all within the broader context of mitochondrial regulation by NO .
Dynamic R&D Competition, Research Line Diversity, and Intellectual Property Rights

This paper develops a simple model of sequential innovations with a diversity of research lines. Competitive strategies of firms for R&D are analyzed at each stage in a sequence of innovations. We compare two alternative regimes of enforcing patent law, as a mechanism to provide adequate incentives for R&D at each stage. The regime that protects the research line gives monopoly rights to an entire line of research, hence limiting the utilization of the previous knowledge and retarding subsequent innovations. The other regime protects the product, which facilitates the use of previous knowledge at the expense of providing inadequate protection to the ideas embodied in the product, and results in underinvestment in the first stage.
Virulence factors of Cryptococcus neoformans

Cryptococcosis is a serious fungal disease in patients with AIDS or other defects in T-cell-mediated host defenses. Cryptococcus neoformans produces several virulence factors, most notably the polysaccharide capsule and phenol oxidase. Molecular studies of cryptococcal virulence factors have contributed to our understanding of the pathobiology of this yeast, and will enable the identification of new targets for antifungal therapy.
Low-power, self-contained, reciprocating micropump through electrolysis and catalyst-driven recombination toward drug delivery applications

Implantable pumps have allowed for substantial improvements in health and are a developing discipline in biomedical engineering, with applications in drug delivery, fluid removal, and research [1-4]. Towards this end, we here propose a novel electrolytic micropump utilizing a platinum based catalyst for cyclic operation. This pump design offers advantages in terms of low power consumption, high reliability, precise flow rates, and simple addition of external micro-controllers. Our system leverages electrolysis of water followed by catalyst-driven recombination of electrolytic gases to achieve a reciprocating motion of a membrane that leads to cyclic dispensing of drug fluids, with a performance rate of approximately 0.3μL/min per mA.
Through-space interactions in spirenes

Abstract Ab initio SCF calculations have been performed on a series of neutral and ionic spirene species: spiro[4.4]nonatetraene, spiro[2.4]heptatriene, spiro[2
Transmission electron microscopy and electron energy loss spectroscopy analysis of ultrathin amorphous carbon films

Transmission electron microscopy (TEM) and analytic TEM were used to study the microstructure of amorphous carbon (a-C) films of thickness in the range of 5–100 nm deposited on Si(100) by radio-frequency (rf) sputtering. High-resolution cross-section TEM revealed a two-layer structure consisting of the a-C film and an ultrathin interface layer, in agreement with electron energy loss spectroscopy results. The presence of a 35-A-thick interface layer (regardless of the deposition conditions) indicates that nucleation and initial growth of the a-C films were mainly controlled by the substrate surface condition. Mass-thickness contrast in bright-field TEM images showed an interface layer denser than the a-C film. This layer, believed to consist of Si, a-C, and SiC, enhances the adhesion of the film to the silicon substrate and accommodates the residual stress in the film. High-resolution cross-section TEM images revealed the presence of platelike nanocrystallites (∼35 A in size) randomly distributed in the a-C film and oriented parallel to the surface. The possible mechanisms leading to the formation of these nanocrystalline structures are discussed in terms of sputtering phenomena occurring during film deposition.
Stereotactic radiosurgery as an adjunct to surgery and external beam radiotherapy in the treatment of patients with malignant gliomas

Abstract Purpose : To evaluate the efficacy and toxicity of a stereotactic radiosurgery boost as part of the primary management of a minimally selected population of patients with malignant gliomas. Methods and Materials : Between June, 1991 and January, 1994 a stereotactic radiosurgery boost was given to 30 patients after completion of fractionated external beam radiotherapy. The study population consisted of 22 males and 8 females, with a ranged in age at treatment from 5 to 74 years (median: 54 years). Tumor volume ranged from 2.1 to 115.5 cubic centimeters (cc) (median: 24 cc). Histology included 17 with glioblastoma multiforme, 10 with anaplastic astrocytoma, 1 with a mixed anaplastic astrocytoma-oligodendroglioma, and 2 with a gliosarcoma. A complete resection was performed in 9 (30%) patients, while 18 (60%) underwent a subtotal resection, and 3 (10%) received a biopsy only. Fractionated radiation dose ranged from 44 to 62 Gy, with a median of 59.4 Gy. Prescribed stereotactic radiosurgery dose ranged from 0.5 to 18 Gy (median: 10 Gy), and the volume receiving the prescription dose ranged from 2.1 to 158.7 cc (median: 46 cc). The volume of tumor receiving the prescription dose ranged from 70–100% (median: 100%). One to four (median: 2) isocenters were used, and collimator size ranged from 12.5 to 50 mm (median size: 32.5 mm). The median minimum stereotactic radiosurgery dose was 70% of the prescription dose and the median maximum dose was 200% of the prescription dose. Results : With a minimum follow-up of 1 year from radiosurgery, 7 (23%) of the patients are still living and 22 (73%)_have died of progressive disease. One patient died of a myocardial infarction 5 months after stereotactic radiosurgery. Follow-up for living patients ranged from 12 to 45 months, with a median of 30 months. The 1- and 2-year disease-specific survival from the date of diagnosis is 57 [95% confidence interval (CI) 39 to 74%] and 25% (95% CI 9 to 41%), respectively (median survival: 13.9 months). No significant acute or late toxicity has been observed. Conclusions : Stereotactic radiosurgery provides a safe and feasible technique for dose escalation in the primary management of unselected malignant gliomas. Longer follow-up and a randomized prospective trial is required to more thoroughly evaluate the role of radiosurgery in the primary management of malignant gliomas.
Effects of passive immunization of growth hormone-releasing hormone and somatostatin on growth hormone secretion under conditions of high somatostatin tone.

Abstract Pulsatile GH secretion decreases during food-deprivation in the rat. It has been hypothesized that this decrease is due to elevated hypothalamic somatostatin secretion. This is based on the observation that GH increases in food-deprived rats following removal of endogenous somatostatin using passive immunization techniques. Cognizant of the important stimulatory effects of growth hormone-releasing hormone (GHRH) on GH secretion, we sought to determine if this neuropeptide plays any role in mediating GH secretion in food-deprived rats. Male rats were prepared with indwelling venous catheters using sodium pentobarbital anesthesia seven days prior to experimentation. Animals were food-deprived for 72 h, after which control blood samples were drawn from −60 to 0 min. One group was then treated with normal rabbit serum (NRS), while a second group was treated with GHRH antiserum (GHRHab). At 55 min all animals received somatostatin antiserum (SSab). No animal exhibited any spontaneous GH peak during the one hour control period or in the subsequent one hour period following the administration of GHRHab or NRS. Absence of GH pulsatility during food-deprivation, coupled with no decrease in GH levels in food-deprived rats treated with GHRHab suggest that diminished GHRH pulsatility is likely during food-deprivation. Subsequent treatment of these animals with SSab resulted in an identical 2.5 fold increase in GH concentrations. This result suggests that GHRH is not involved in the GH rebound following somatostatin withdrawal in food-deprived rats.
A Comparison of Numerous Lap Joint Theories for Adhesively Bonded Joints

Abstract Numerous authors have investigated the state of stress in the adhesive of adhesively bonded joints. They have made various assumptions concerning the behavior of the adhesive and adherends to yield tractable differential equations which remove the stress singularities which occur at the edges of the bi-material interfaces. By examining several test problems, this paper investigates the effect of these assumptions on predicted adhesive stress. It was found that predicted maximum adhesive shear stress is insensitive to underlying assumptions and that maximum adhesive peel stress is relatively unaffected by most assumptions except that neglecting shear deformation of the adherends can affect results by as much as 30%. Peel stresses from the well known theory of Goland and Reissner which neglects shear deformation of the adherends and makes several inconsistent assumptions vary as much as 30% from stresses from a consistent lap joint theory which considers shear deformation of the adherends. However,...
Rural-to-rural migrants: the neglected component of rural population growth.

An examination of the importance of rural-to-rural migration in the United States is presented. Data are from a 1977 telephone survey of migrants and residents in 75 high net in-migration counties in the North Central region. Rural-origin and urban-origin migrants are compared with rural residents and with each other. Characteristics examined include age education and income. (ANNOTATION)