cssi/SciSciGPT-SciSciNet huggingface dataset:
971–58 Does Regional Ischemic Preconditioning Affect Collateral Blood Flow to Remote Myocardium During Subsequent Occlusion?: Insights Using Myocardial Contrast Echocardiography

Although it has recently been shown that brief periods of ischemia in one vascular bed protect distant myocardium from subsequent sustained coronary occlusion (occ), its mechanisms are unclear. We hypothesized that “preconditioning” (PC) with repetitive transient ischemia in one coronary bed induces an acute increase in collateral blood flow to a distant bed undergoing subsequent prolonged ischemia, which manifests as a reduction in risk area (RA) size. Accordingly, 11 open-chested dogs were studied: 6 had PC with 4 episodes of 5 min left circumflex (LCX) branch occ plus 5 min reflow, followed by 1 hr left anterior descending artery (LAD) occ, while 5 received 1 hr LAD occ only. In-vivo LAD RA was serially depicted using myocardial contrast echocardiography (MCE). Regional flow was measured using radiolabeled microspheres. During the 1 hr LAD occ, MCE and microsphere measurements were made at 10 and 50 min into occ. To assess the original LAD RA size prior to PC, MCE and microsphere measurements were made during an initial 90 sec LAD occ before intermittent LCX occ. RA was planimetered from the MCE images and expressed as percent of the short-axis. In the PC dogs, the original LAD RA prior to PC was 30 ± 8%, and decreased after intermittent LCX occ to 23 ± 10% at 10 min, and 15 ± 11% at 50 min, into the 1 hr LAD occ (p l 0.03), due to new contrast enhancement at the lateral and epicardial borders of the RA. This net 52% reduction paralleled progressive increases in normalized epicardial flow to the LAD bed at these 3 stages (0.45 ± 0.17 to 0.58 ± 0.14 to 0.66 ± 0.18, P l 0.001). In comparison, in control dogs, there was no significant change from the original LAD RA (36 ± 7%) to that at 10 (38 ± 3%) nOr 50 (36 ± 3%) min into LAD occ. The slight increase noted in normalized epicardial flow during these 3 stages in the controls (0.31 ± 0.11 to 0.33 ± 0.010 to 0.38 ± 13, P l 0.01) was significantly less than in PC dogs, and was not detected with MCE. In conclusion, in this canine model, collateral flow to an occluded vascular bed is enhanced by prior brief ischemia/reperfusion in a distantly located coronary bed. Furthermore, the resulting decrease in RA size appears ongoing during the sustained occ. “Remote” PC may facilitate the recruitment of preformed collaterals situated between the 2 beds, and this phenomenon may help explain the reductions in infarct size associated with this PC model.
In situ Raman spectroscopic study of transient polyhedral distortions during cesium ion exchange into sitinakite

The Na-form of the synthetic counterpart of the mineral sitinakite (sitinakite-Na) was studied in situ for the ion exchange systems of Na→Cs and Na→H→Cs using time-resolved Raman spectroscopy. Raman spectral mode analysis was performed based on a comparative study of previous titanium silicate Raman spectroscopy, as well as time-resolved X-ray diffraction studies. The Raman spectrum of sitinakite can be broken down to three main groups of bending and stretching modes, respectively: Ti-O-Ti, Si-O-Ti, and O-Ti-O bends between 200 and 400 cm−1; and Ti-O stretch between 400 and 625 cm−1. During Na-form to H-form ion exchange, rapid red shifts were observed in absolute peak positions, as well as relative changes between peak positions, indicating a symmetry change. TiO6 polyhedral groups distort as hydroxyl groups form on the TiO6 octahedra. Upon Cs exchange into the H-form, a rapid, two-step blue shift was observed for all peak positions, which indicated that the eight membered-ring becomes more circular. Upon Cs exchange into the Na-form, slow changes of peaks in the Raman spectrum indicated up to four discrete polyhedral distortions during ion exchange. The advantage of Raman spectroscopy in this study was the observation of transient polyhedral distortions for the initial swelling of sitinakite while immersed in deionized H2O and during H and Cs ion exchange in the crystal structure. Previous X-ray diffraction studies were not of sufficient resolution to model H2O swelling effects and framework polyhedral distortions during ion exchange, thus Raman spectroscopy offers a complementary tool to measure changes in framework geometry in situ during ion exchange. The results presented here are directly relevant to other ion exchange research on titanium silicates, zirconium silicates, aluminum silicates, and aluminum phosphates. Additionally this work shows the usefulness of in operando experiments, conducted in deliberately variable environments, which can monitor the molecular dynamics of a system, collect information concerning structure-response mechanisms, and capture the catalytic parameters for the reaction/process.
Integrating data and compute-intensive workflows for uncertainty quantification in large-scale simulation: application to model-based hazard analysis

Complex inference from simulation ensembles used in uncertainty quantification leads to twin computational challenges of managing large amount of data and performing CPU-intensive computing. While algorithmic innovations using surrogates, localization and parallelization can make the problem feasible, one still has very large data and compute tasks. The problem of dealing with large data gets compounded when data warehousing and data mining are intertwined with computationally expensive tasks. We present here an approach to solving this problem by using a mix of hardware suitable for each task in a carefully orchestrated workflow. The computing environment is essentially an integration of Netezza database and high-performance cluster. It is based on the simple idea of segregating the data-intensive and compute-intensive tasks and assigning the right architecture for them. We present here the layout of the computing model and the new computational scheme adopted to generate probabilistic hazard maps.
Microsatellite variation in marine, freshwater and anadromous fishes compared with other animals

Author(s): DeWoody, JA; Avise, JC | Abstract: From a total of 524 microsatellite loci considered in nearly 40 000 individuals of 78 species, freshwater fish displayed levels of population genetic variation (mean heterozygosity, h=0.46, and mean numbers of alleles per locus, a=7.5) roughly similar to those of non-piscine animals (h=0.58 and a=7.1). In contrast, local population samples of marine fish displayed on average significantly higher heterozygosities (h=0.79) and nearly three times the number of alleles per locus (a=20.6). Anadromous fish were intermediate to marine and freshwater fish (h=0.68 and a=11.3). Results parallel earlier comparative summaries of allozyme variation in marine, anadromous, and freshwater fishes and probably are attributable in part to differences in evolutionarily effective population sizes typifying species inhabiting these realms. (C) 2000 The Fisheries Society of the British Isles.
On eulerian irregularity in graphs

A closed walk in a connected graph G that contains every edge of G exactly once is an Eulerian circuit. A graph is Eulerian if it contains an Eulerian circuit. It is well known that a connected graph G is Eulerian if and only if every vertex of G is even. An Eulerian walk in a connected graph G is a closed walk that contains every edge of G at least once, while an irregular Eulerian walk in G is an Eulerian walk that encounters no two edges of G the same number of times. The minimum length of an irregular Eulerian walk in G is called the Eulerian irregularity of G. We present some results and open questions in this area of research.
Free energy of a static quark-antiquark pair and the renormalized Polyakov loop in three flavor QCD

We study the free energy of a static quark-antiquark ($Q\overline{Q}$) pair at finite temperature in three flavor QCD with degenerate quark masses using ${N}_{\ensuremath{\tau}}=4$ and $6$ lattices with Asqtad staggered fermion action. The static free energy was calculated for different values of the quark mass and the entropy contribution at large distances has been extracted. We also calculate the renormalized Polyakov loop following the approach by Kaczmarek et al.
Platelet activation with combination of ionophore A23187 and a direct protein kinase C activator induces normal secretion in patients with impaired receptor mediated secretion and abnormal signal transduction.

Abstract Defects in signal transduction mechanisms may underlie the impaired aggregation and secretion in patients with congenital platelet function defects (CPD). Both protein kinase C (PKC) induced pleckstrin phosphorylation and cytoplasmic Ca2+ mobilization play a major role in secretion. We postulated that combined platelet activation with a cell permeable direct PKC activator 1,2-dioctanoyl-sn-glycerol (DiC8) and ionophore A23187, which possibly bypass the steps involved in the intracellular synthesis of two major mediators (inositol trisphosphate, diacylglycerol), may induce normal dense granule secretion in patients with impaired receptor mediated secretion. We studied eight CPD patients with abnormal aggregation and secretion in response to several different surface receptor-mediated agonists despite the presence of normal dense granule contents. Receptor mediated Ca2+ mobilization and/or pleckstrin phosphorylation were abnormal in seven patients. Platelet activation with a combination of ADP (8 μM) with DiC8 (200 μM) or A23187 (10 μM) improved secretion in four patients. However, platelet activation with a combination of 200 μM DiC8 with 10 μM A23187, or 100 μM DiC8 with 5 μM A23187 induced normal secretion in platelet-rich plasma in all patients. These studies suggest that in such patients with CPD the ultimate process of exocytosis or secretion per se is intact and impaired secretion results from abnormalities in early signal transduction events, possibly upstream of diacylglycerol formation and calcium mobilization. Detailed studies are needed to delineate the specific abnormalities in these heterogenous patients with signal transduction defects.
A color reaction of pentose phosphate esters substituted in position 5.

Abstract 1. 1. A color reaction is described which differentiates between pentose-5-phosphates and free pentose and other pentose esters. 2. 2. The application of this reaction for the detection of pentose-5-phosphates in presence of other pentose esters is discussed.
Is defibrillation testing necessary

With advancements in implantable cardioverter defibrillator (ICD) technology, the practice of performing defibrillation threshold (DFT) testing at the time of implantation has been questioned. With availability of biphasic waveforms, active cans, and high-output devices, opponents claim that DFT testing is no longer necessary. Clinical trials demonstrating the efficacy of ICDs in prevention of sudden cardiac death have, however, all used some form of defibrillation testing. This debate is fueled by the absence of data from randomized prospective trials evaluating the role of DFT testing in predicting clinical shock efficacy or survival. This review discusses both sides of the argument.
Maintaining a Nutrient Database in a Changing Marketplace: Keeping Pace with Changing Food Products—A Research Perspective

Abstract Maintenance of a food and nutrient database for dietary research involves providing the right foods and nutrients for study participants, while keeping the database a size and format that can be updated rapidly and completely. The database must include (1) foods reported by study participants, (2) new foods that appear in the marketplace, (3) nutrients of research interest, and (4) for each food, a nutrient profile with no missing values. For efficient and timely updating, the database is kept to a manageable size by (1) grouping foods of similar nutrient content into a single database entry; (2) adding only foods widely consumed by most study participants; (3) including foods as usually prepared; (4) including foods only if adequate nutrient data are available; (5) allowing ingredients to be varied to provide multiple nutrient profiles from a single recipe, and (6) providing researchers the ability to add foods specific to their study to their individual database. The Nutrition Data System for Research (NDS-R) maintained by the Nutrition Coordinating Center at the University of Minnesota is a research tool used to collect and analyze dietary intake data. The food and nutrient database within NDS-R includes commodity and brand name foods commonly consumed in the United States, as well as foods for special ethnic and age group populations. Currently, this database contains 108 nutrients or food components for 17 000 foods.
MScreen An Integrated Compound Management and High-Throughput Screening Data Storage and Analysis System

High-throughput screening (HTS) has historically been used by the pharmaceutical industry to rapidly test hundreds of thousands of compounds to identify potential drug candidates. More recently, academic groups have used HTS to identify new chemical probes or small interfering RNA (siRNA) that can serve as experimental tools to examine the biology or physiology of novel proteins, processes, or interactions. HTS presents a significant challenge with the vast and complex nature of data generated. This report describes MScreen, a Web-based, open-source cheminformatics application for chemical library and siRNA plate management, primary HTS and dose-response data handling, structure search, and administrative functions. Each project in MScreen can be secured with passwords or shared in an open-information environment that enables collaborators to easily compare data from many screens, providing a useful means to identify compounds with desired selectivity. Unique features include compound, substance, mixture, and siRNA plate creation and formatting; automated dose-response fitting and quality control (QC); and user, target, and assay method administration. MScreen provides an effective means to facilitate HTS information handling and analysis in the academic setting so that users can efficiently view their screening data and evaluate results for follow-up.
Retinal synaptic pathways underlying the response of the rabbit local edge detector.

We studied the circuitry that underlies the behavior of the local edge detector (LED) retinal ganglion cell in rabbit by measuring the spatial and temporal properties of excitatory and inhibitory c...
Social support and psychosocial adjustment to rheumatoid arthritis: Quantitative and qualitative findings.

One hundred twenty-nine individuals with rheumatoid arthritis were interviewed, and their satisfaction with several aspects of social support was rated. Quantitative analyses showed that patients' overall support satisfaction was related to health care providers' ratings of their psychosocial adjustment, independent of patients' demographic characteristics, illness duration, disease activity, and functional disability. Furthermore, the relation between support satisfaction and psychosocial adjustment increased as a function of patients' level of disability, suggesting a stress-buffering function of support. Among the important qualitative findings emerging from content analyses of interview material was that disruptions in relationships with actual and potential support providers constituted a source of stress. However, several participants stated that the illness had actually strengthened valued relationships. Patients' views of helpful and unhelpful support gestures are also classified and discussed. Directions for future research on the support process are suggested.
Long-term reproducibility of respiratory gas exchange measurements during exercise in patients with stable cardiac failure.

Present-day technology has greatly facilitated the monitoring of respiratory gas exchange in the clinical exercise laboratory. Despite the growing use of these techniques to assess the severity and progression of disease or therapeutic response in patients with heart failure, the long-term reproducibility of oxygen uptake ( V ˙ O 2 ), carbon dioxide production, minute ventilation, heart rate (HR), and blood pressure at rest and during incremental exercise in such patients, to our knowledge, has not been evaluated. Therefore, the purpose of this study was to quantify the reproducibility of these variables along with exercise duration, maximum V ˙ O 2 ( V ˙ O 2 max) and anaerobic threshold in a group of 16 patients (61 ± 7 years, 14 male) with chronic, stable cardiac failure of varying severity and etiology who had five or more incremental treadmill exercise tests over a period of time that ranged from 3 to 22 months. For each variable, reproducibility was represented by the coefficient of variation (CVAR). Except for exercise duration, CVAR was not a function of the severity of heart failure and, for all variables, patient-to-patient variation in CVAR was approximately 9 percent. The maximum CVAR for HR, systolic blood pressure, V ˙ O 2 , and V ˙ O 2 max was generally below 10.5 percent and for exercise duration and anaerobic threshold it was less than 12.5 percent. Based on this retrospective analysis, it is concluded that reproducible respiratory gas exchange and HR exercise responses are obtainable over extended periods of time in patients with stable, chronic cardiac failure. Exercise duration, however, is less reproducible in patients with moderate to severe failure. (Chest 1990; 97:12-17)
SOME OBSERVATIONS ON METRIOPTERA ROESELII (GRYLLOPTERA: TETTIGONIIDAE) IN MAINE, NEW HAMPSHIRE, AND MASSACHUSETTS

Metrioptera ( Roeseliana ) roeselii (Hgb.) was first introduced into the Montreal, Que., area before 1952. By 1965 it had been collected in western and southern New York State. This paper records it from Maine, Massachusetts, and New Hampshire for the first time, and discusses the populations. Eventual establishment of M . roeselii over all of New England is predicted.
INTEGRATED MULTILAYER HIGH ASPECT RATIO MILLIACTUATORS

Abstract We report here an integrated multilayer high aspect ratio process, and mm-sized electromechanical actuator structures fabricated by this process. The high aspect ratio microfabrication process allows the generation of structures an order of magnitude larger than conventional structures in all three dimensions, while still retaining the minimum in-plane features. We will describe a detailed example of a 1-mm-sized microfabricated actuator with a linearized output capability of 0.2 mN when driven at 60 V. In addition to the high aspect ratio microfabrication process, the high force output is achieved through an area-efficient design and a large-signal linearization scheme. The area-efficient design allows full utilization of the chip area for energy conversion. The large-signal linearization scheme permits a linearized force output with driving voltages as large as the biasing voltage. This increased output force enables the batch-fabricated microactuators to be used in many new, practical applications in which the microactuators are required to move an additional load as well as their own mass. Other structures made possible by this process are fully-integrated wobble micromotors with notched pin-joints for extended high aspect ratio gaps between rotors, stators and axles.
Simplified dispatcher instructions improve bystander chest compression quality during simulated pediatric resuscitation.

Aim Cardiopulmonary resuscitation (CPR) quality is associated with survival outcomes after out-of-hospital cardiac arrest. The objective of this study was to evaluate the effectiveness of simplified dispatcher CPR instructions to improve the chest compression (CC) quality during simulated pediatric cardiac arrest in public places.
Collaborative practice in advanced practice nursing in acute care

APN in the United States encompasses a variety of collaborative models of care. Collaborative relationships with other disciplines such as medicine, pharmacy, social service, and physical, respiratory, and occupational therapy are an important component of the APN role. The collaborative relationship of the APN and physician is a unique one for providing optimal patient and family care. As changes in healthcare in acute care settings continue to occur, additional collaborative models for APN and physician care will only continue to help in meeting the healthcare needs of patients.
Vision Impairment and Driving

Driving is the primary mode of travel in many countries. It facilitates the performance of routine daily activities and is thus integral with the concept of quality of life. Vision is inarguably a fundamental component of safe driving. Drivers with certain eye conditions reduce their driving exposure and restrict their driving to the safest times, yet there is preliminary evidence that some eye conditions increase the risk of crashes. Visual acuity is only weakly related to crash involvement, whereas peripheral vision appears to play a more critical role. Color vision deficiency by itself is not a threat to safe driving. Based on the current literature, it is unclear whether other types of visual sensory impairment have a significant impact on driving safety and performance. Tests of visual attention and processing speed show great promise as methods of identifying high-risk drivers. There is a serious need for well-designed studies in key practical areas, such as the safety of low-vision drivers who use bioptic telescopes, the impact of monocular vision impairment on safety, and the effectiveness of vision rescreening policies after initial licensure. For ophthalmologists to guide patients about driving fitness, valid and reliable assessment tools must be developed and made widely available.
Cone beam computed tomography angiogenesis imaging: preliminary studies

The purpose of this study is to demonstrate the feasibility of performing cone beam CT angiogenesis imaging (CBCTAI) using a cone beam CT scanner prototype. We have developed a cone beam breast CT imaging technique that is able to detect a ~2 mm tumor in live mice and have expanded the imaging to include visualization of tumor vessels. The CBCT prototype consisted of a modified clinical CT scanner and a flat panel detector. This CBCT scanner prototype was used for a series of preliminary contrast studies with live mice: contrast-to-scan time delay, contrast for tumor vessel enhancement (comparison with histology) and early tumor vessel development imaging. The results of the live mice studies demonstrate that good image quality can be achieved with this prototype demonstrating the feasibility of CBCTAI. Achieving the CBCTAI technique on the cone beam breast CT imaging modality will significantly advance breast cancer detection, diagnosis and treatment.
Automatic, sterile, and apyrogenic delivery of PET radiotracers from the cyclotron to the patient

Abstract An automatic delivery remote injection system has been developed to administer either 13 N-labelled ammonia, or 15 O-labelled water or 18 F-labelled FDG to patients. Automation increases the throughout and efficiency of the PET center, and remote dose administration ensures patient safety and reduces the radiation exposure to the technologist supervising the radiopharmaceutical injection. The remote dose administration apparatus utilizes a syringe pump to transfer liquid activity and a solenoid three-way valve to switch between lines connected to a patient and a receiving vial. To ensure apyrogenicity and sterility of the injected product, the entire system is washed with sterile water before it is used. Since the tracer is delivered in an ~ 8 ml bolus of water, the next delivery through the system is considered safe for injection if pyrogens are not detected at a threshold of 3 endotoxin units per ml (EU/ml) in the wash. Time delayed tests shows that the system may be left unused for up to 6 h before the wash must be repeated.
SU-E-T-841: The Potential of Probablistic Optimization for Tumor Motion with IMRT

Purpose: To demonstrate the feasibility of using probabilistic optimization for helical tomotherapy (HT) treatment planning of intrafraction moving targets: an alternative to motion management by active tracking. Methods: Realistic but regular purely transverse elliptical motion was produced with the Washington University 4D Motion Phantom to supplement previous work that contained either transverse and longitudinal or just longitudinal motions with varying amount of randomness and drifts. Dose perturbations due to motion were measured with Gafchromatic EBT film. A small (12cm diameter, 12 cm long) Virtual WaterTM cylindrical phantom is used in a Hi‐Art IITM (TomoTherapy Inc., Madison, WI) HT device. The treatment plan consists of a 9 cm ring target (98% gets the prescribed dose) with a 4 cm diameter central avoidance region (gets half the prescribed dose on average) for 9 cm along the length of the cylinder. Results: The transverse motion needs to be much larger than average transverse respiratory motions for lungtumors for the motion to cause unacceptable blurring. This and other studies demonstrate that HT is robust to breathing motion interference with the beamlet modulation, but care must be taken in the longitudinal direction for irregular breathing with a low frequency drift that interferes with the couch motion. Within the target, less than a 1% dose perturbation is observed between 0.10 < (gantry period)/(breathing period) < 10. Conclusions: With reasonable care to approximately regularize the patient's breathing, the dose distribution exhibits a dominantly ‘blurred’ response to the motion, so a single motion probability distribution function (pdf) can approximate the respiratory motion well enough to enable the use of probabilistic optimization. HT's delivery over multiple gantry rotations and patient breathing cycles enables sufficient dose smoothing for probabilistic optimization to apply to hypofractionated HT deliveries. The author, T. Mackie, has ownership interests in TomoTherapy, Inc., which is commercializing helical tomotherapy. This work was funded by NIH/NCI K25 CA119344.
Baby-Boomers and Financial Markets: A Relationship in the Making

Stocks market, bond prices and housing values have all been rising ever since baby-boomers entered their prime savings age in early 1980s. Now, as baby-boomers begin to retire in 2007, these markets are likely to enter a reverse path. However, prudent financial planning and wise political decision-making can reduce the severity of potential crisis and ensure the long run stability.
Stratosphere–Troposphere Coupling during Spring Onset

Abstract The authors perform an observational study of the relation between stratospheric final warmings (SFWs) and the boreal extratropical circulation. SFW events are found to provide a strong organizing influence upon the large-scale circulation of the stratosphere and troposphere during the period of spring onset. In contrast to the climatological seasonal cycle, SFW events noticeably sharpen the annual weakening of high-latitude circumpolar westerlies in both the stratosphere and troposphere. A coherent pattern of significant westerly (easterly) zonal wind anomalies is observed to extend from the stratosphere to the earth’s surface at high latitudes prior to (after) SFW events, coinciding with the polar vortex breakdown. This evolution is associated with a bidirectional dynamical coupling of the stratosphere–troposphere system in which tropospheric low-frequency waves induce annular stratospheric circulation anomalies, which in turn, are followed by annular tropospheric circulation anomalies. The reg...
The effect of levothyroxine treatment on resting energy expenditure of hypothyroid dogs

Thirty adult, client-owned dogs were diagnosed with hypothyroidism based on history, physical examination findings, hematologic and biochemical abnormalities, thyrotropin (TSH) response testing, endogenous canine thyrotropin (cTSH) concentration, or both, and total serum thryoxine concentration. All dogs received levothyroxine (L-thyroxine) at an initial dose of 22 pgkg PO sid in either a tablet (13 dogs) or chewable form (17 dogs). Energy expenditure of each dog during apparent rest was estimated with an open-flow indirect calorimetry system by determining the rates of carbon dioxide production and oxygen consumption. Energy expenditure of apparent rest (EE) was lower in untreated hypothyroid dogs compared with reference values for EE. After treatment with L-thyroxine, EE of the hypothyroid dogs was significantly (P < .05) higher than pretreatment values. anine hypothyroidism is a gratifying disease to treat: C thyroid hormone supplementation resolves the metabolic abnormalities associated with canine hypothyroidAlthough many dogs respond adequately to oncedaily administration of levothyroxine @-thyroxine), some dogs require twice-daily treatment to achieve and maintain a clinically euthyroid ~tate.~ Therapy is monitored by measuring serum thyroxine (T4) concentration 4-6 hours after oral L-thyroxine administration (postpill testing) and by assessing resolution of clinical signs of hypothyroidism. Unfortunately, oversupplementation is not easily detected by current monitoring methods4 Basal metabolic rate (BMR) is a quantitative measure of total body energy production. The metabolic effects of thyroid hormone account for approximately 50% of BMR.5 As such, BMR determinations using indirect calorimetry have been used in studies of people with hypothyroidism to assess response to thyroid hormone replacement the rap^.^ A patient is considered adequately supplemented when BMR returns to normal. Indirect calorimetry is an accurate, sensitive “bedside” method of determining BMR or energy expenditure in dogs and humans.Gi0 Energy expenditure of apparently resting dogs (EE) is defined as the energy expended by the dog when it is in a postabsorptive state under thermally neutral conditions. Measurements of EE range from being almost equivalent to BMR to as much as 25% higher? Noninvasive estimations of EE are made by measuring the rate of oxygen consumption (60,) and the rate of carbon dioxide production (Vco,) using indirect The purpose of this study was to determine the effect of
The Good Old Days Were Better: Agrarian Collapse and Tectonics

The theory of plate tectonics contends that the continental plates occupied by humanity are in motion. The hypothesis of agrarian collapse (HA C) holds that gradual, as well as seismic, earth movement can induce ground slope change and modify land-to-sea level relationships, thereby altering the distribution of surface and subsurface runoff, which can lead to abandonment of agricultural land. Mechanical principles underlying ongoing abandonment are detailed for large-scale irrigation systems of the Andean Cordillera ATegra. These principles are compatible with a historical scenario integrating urban development at pre-Hispaic Chan Chan, capital of the Chimor polity, with expansion, reform, and collapse of the city's agricultural hinterland. The applicability of the mechanics of agrarian collapse to two other centers of past civilization is briefly considered. [agriculture, complex society, applied archeology, Peru]
Growth hormone enables effective nutrition by peripheral vein in postoperative patients: a pilot study.

The purpose of this pilot study was to investigate the metabolic effects of growth hormone (GH) (Humatrope, Eli Lilly & Co., Indianapolis, IN) administration in postoperative (PO) patients receiving peripheral vein nutrition. Seven, well-nourished, nondiabetic patients undergoing elective surgical procedures were given either no drug (n = 3), GH 30 micrograms/kg/day (n = 2), or GH 60 micrograms/kg/day (n = 2) sub-Q daily until eating, up to 7 days PO. All the patients received 5% dextrose with electrolytes in the first 24 hours PO and then received calories at 80 +/− 5% of the measured resting energy expenditure (REE) and amino acid at 1 g/kg/day with electrolytes, vitamins, and minerals. There were no significant outcome differences between the 30 and 60 micrograms/kg/day groups and, therefore, these groups were analyzed together (n = 4). By day 6 of the study, the GH group had a significant reduction in the respiratory quotient (RQ) measured by indirect calorimetry; an increase in nitrogen retention; an...
Introducing Products Into Export Markets: Success Factors

Success factors in international product entry are still not sufficiently understood. Evidence from 130 published instances of international product entries is analyzed. The findings reveal that factors responsible for international commercial success are different for small and large firms. A number of hypotheses are formulated for future testing on the basis of this exploratory study.
Essay: Accelerators, Beams and Physical Review Special Topics - Accelerators and Beams

Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.
Non-adiabatic non-abelian geometric phase

Abstract The non-integrable geometric phase factor is generalized to a non-abelian phase factor which in the adiabatic limit is the Wilczek-Zee generalization of the Berry phase. It is then extended to the evolution of mixed states. A theorem of Narasimhan and Ramanan is used to relate the gauge field connection to the generalized geometric connection.
Calculation of electron transport in multiterminal systems using complex absorbing potentials

A method to calculate the transmission coefficient in multiterminal systems is presented. By adding a complex absorbing potential to the Hamiltonian of the semi-infinite leads, the problem of inverting an infinite dimensional matrix is transformed into a finite dimensional eigenvalue problem. Using this approach transmission coefficients are calculated for all energies at once. The accuracy of the approach is demonstrated with an analytically solvable model system. Numerical examples of a four-terminal graphene cross junction and six-terminal carbon nanotube junction are presented.
Evolution of the autosomal chorion cluster in Drosophila. IV. The Hawaiian Drosophila: rapid protein evolution and constancy in the rate of DNA divergence.

Autosomal chorion geness18, s15, ands19 are shown to diverge at extremely rapid rates in closely related taxa of HawaiianDrosophila. Their nucleotide divergence rates are at least as fast as those of intergenic regions that are known to evolve more extensively between distantly related species. Their amino acid divergence rates are the fastest known to date. There are two nucleotide replacement substitutions for every synonymous one. The molecular basis for observed length and substitution mutations is analyzed. Length mutations are strongly associated with direct repeats in general, and with tandem repeats in particular, whereas the rate for an average transition is twice that for an average transversion.
Face Recognition from Incomplete Measurements via ℓ1-minimization

In this work, we consider a homotopic principle for solving large-scale and dense l1underdetermined problems and its applications in image processing and classification. We solve the face recognition problem where the input image contains corrupted and/or lost pixels. The approach involves two steps: first, the incomplete or corrupted image is subject to an inpainting process, and secondly, the restored image is used to carry out the classification or recognition task. Addressing these two steps involves solving large scale l1minimization problems. To that end, we propose to solve a sequence of linear equality constrained multiquadric problems that depends on a regularization parameter that converges to zero. The procedure generates a central path that converges to a point on the solution set of the l1underdetermined problem. In order to solve each subproblem, a conjugate gradient algorithm is formulated. When noise is present in the model, inexact directions are taken so that an approximate solution is computed faster. This prevents the ill conditioning produced when the conjugate gradient is required to iterate until a zero residual is attained.
Pain and Sensory Symptoms in Parkinson's Disease

In this communication we discuss the clinical features and pathophysiology of primary sensory symptoms in Parkinson's disease.
Abiotic stress in rice. An "omic" approach.

Abiotic stress can impose limitations on crop productivity and also limit land available for farming, often in regions that can ill afford such constraints, thus highlighting a greater need for understanding how plants respond to adverse conditions with the hope of improving tolerance of plants to
Leydig cell steroidogenesis in aging rats

Recent studies from our and other laboratories have shown that Leydig cells, the testicular cells responsible for testosterone production; become steroidogenically hypofunctional with age. Herein we review some of what we now know about the mechanisms by which this occurs, and some among the many remaining uncertainties in our understanding of Leydig cell aging. To help shed light on how Leydig cells age, we also briefly discuss the regulation of Leydig cell differentiation during puberty and of Leydig cell function in adult animals.
Effects of phlorizin and ouabain on the polarity of mouse 4-cell/16-cell stage blastomere heterokaryons.

Cell polarity is thought to be required for the efficient production of nascent blastocoele fluid, which begins at the 16-cell stage of mouse preimplantation development. In this study the 4-cell/16-cell blastomere heterokaryon was used to test the hypothesis that solute transport across the apical membrane domain induces the apical-basal axis of organelle distribution across polar 16-cell-stage blastomeres. Fusion of 4-cell/16-cell blastomere pairs resulted in a population of heterokaryons of which 65% were polar (contain an apical plasma membrane domain from a polar 16-cell-stage plasma membrane insert) and 30% were apolar (contain an apolar 16-cell-stage plasma membrane insert). Polar heterokaryons were distinguished from apolar ones by labeling their apical domains with fluorescent succinylated concanavalin A. In polar heterokaryons, both nuclei (labeled with Hoeschst 33242) were immediately subjacent to the apical plasma membrane domain, while in apolar heterokaryons both nuclei were located centrally. Two inhibitors of apical transmembrane solute transport--phlorizin, which inhibits brush border (apical) Na+/glucose symporters, and ouabain, which inhibits Na+/K+-ATPase, thereby modifying the transmembrane Na+ gradient--were examined for their effect on nuclear position in polar and apolar heterokaryons after a 4-hr incubation in either inhibitor. Both ouabain (L.M. Wiley, 1984, Dev. Biol. 105, 330-342) and phlorizin (this study) had a biphasic effect on the rate of nascent blastocoele fluid accumulation such that at lower concentrations (ouabain, 10(-5) M; phlorizin, 10(-6) M) fluid accumulation was accelerated and at higher concentrations (both inhibitors, 10(-4) M) fluid accumulation was delayed. In polar heterokaryons, both concentrations of each inhibitor caused the nuclei to become displaced basally from their normal location against the apical plasma membrane domain. Both nuclei, however, remained on the axis of polarity passing through the apical domain. The magnitude of displacement was greater at higher concentrations of either inhibitor. Neither inhibitor affected nuclear position in apolar heterokaryons. These observations agree with the hypothesis that apical plasma membrane solute transport maintains the asymmetric organelle distribution across the apical-basal axis of polar 16-cell-stage blastomeres.
Maximum likelihood estimation for weighted distributions

Abstract We study the effect of weight functions on estimates of parameters from exponential families, and families with monotone likelihood ratio. We illustrate our results on two commonly used indices in meta-analyses, p -values and t -statistics.
Practical Aspects of EIK Technology

Significant progress in modeling and manufacturing technologies open wide possibilities for performance improvements of millimeter-wave vacuum electron devices. However, many practical aspects should be considered to realize reliable long-life high-power sources. These are: thermal and RF stability, materials and assembly sensitivity to manufacturing, electrical stresses, cathode poisoning prevention, thermal beam effects, and many others. We address the full spectrum of design and manufacturing aspects while developing state-of-the-art extended interaction klystrons (EIKs). EIKs provide unprecedented RF performance and reliability in a compact user-friendly package. This paper discusses EIK design methodology and manufacturing concepts stating self-imposed restrictions and design modifications enhancing power capability, bandwidth, and extending operating frequencies into the terahertz region.
Impact of the human genome project on medical practice.

Background: The Human Genome Project is a coordinated effort to define the human genetic blueprint. The goals include construction of a variety of maps of the human genome, including the identification and localization of all genes. The discovery of genes responsible for human diseases has had a significant impact on the practice of medicine. Methods: Methods for defining the human genome include cytogenetic, physical, and genetic mapping techniques. A variety of strategies have been used to identify human genes, especially those genes that are responsible for disease. Once a disease gene has been identified, this information can be used to develop new diagnostic and therapeutic procedures. Results: A number of disease genes have already been identified, leading to improved diagnosis and novel approaches to therapy. A new type of mutation, trinucleotide repeat expansion, has been found to be responsible for at least seven diseases with an unusual inheritance pattern. Conclusions: Materials and technology generated by the Human Genome Project and related research have provided important tools for the diagnosis and treatment of patients afflicted with genetic diseases.
A longitudinal investigation of heavy drinking and physical dating violence in men and women

Examinations of heavy drinking and dating violence have typically focused on either female victimization or male perpetration; yet recent findings indicate that mutual aggression is the most common pattern of dating violence. The current study investigated the relation between heavy drinking and dating violence for both men and women. Participants (N=2247) completed surveys that assessed their heavy drinking and dating violence frequency across the first three years of college. Findings indicated that heavy drinking and dating violence were both relatively stable across time for men and women, but the relation between heavy drinking and dating violence differed by gender. For men, heavy drinking and dating violence were concurrently associated during their freshman year (Year 1), whereas for women heavy drinking during their sophomore year (Year 2) predicted dating violence in their junior year (Year 3). In addition to providing educational material on healthy relationships and conflict resolution techniques, intervention efforts should target both heavy drinking and dating violence for men during or prior to their freshman year of college, whereas women may primarily benefit from efforts to reduce their heavy drinking.
A World Flying Apart? Violent Nationalist Conflict and the End of the Cold War

Recent events around the world have convinced political scientists and policymakers that nationalist conflicts are an important feature of the post-Cold War world. Conflicts in Bosnia, Chechnya, Kosovo, and Kurdistan have all been prominent in headlines in recent years; but such conflicts are not just a post-Cold War phenomenon, and many have been going on for decades. This article outlines the scope of this phenomenon - violent conflicts between nationalist groups within states - in the post-war period. It presents a dataset of violent nationalist conflicts within states from 1945 to 1996, measuring cases in terms of initiation, duration, and intensity of conflict, and comparing this effort to other intrastate conflict data collections. The characteristics of these conflicts before and after the Cold War are examined, to test the popular notion that the end of the Cold War has 'unleashed' a new era of nationalist strife. This survey concludes that these conflicts are not simply a post-Cold War phenomenon, nor has the end of the Cold War brought an unprecedented wave of new nationalist conflicts to the world. On the contrary, many such conflicts do get resolved, and more have been resolved in the past ten years - particularly by peaceful methods - than in any comparable period in recent history.
Un modelo animal de diadas cooperativas: Puntos conceptuales y metodológicos

Probablemente la forma de cooperaci6n que mas se ha expandido en animales ocurre cuando los individuos aprenden a coordinar conductas para obtener consecuencias comunes. En una variedad de especies la coordinacion se caracteriza por el cortejo y la agresion. No obstante, se le ha restado importancia al significado de las acciones coordinadas favoreciendo asi la perspectiva de la conducta individual con respecto a lo que se aprende y a lo que se procesa. Generalmente, la teoria del aprendizaje ha seguido la sugerencia de Skinner de que las mismas "leyes del aprendizaje" que se basan en consecuencias contingentes a la conducta son suficientes tanto para la cooperacion como para la conducta individual. Esta sugerencia ha recibido apoyo de modelos de cooperacion que minimizan la interaccion social desarrollados en el laboratorio con sujetos animales o con humanos. A los participantes fisicamente se les aisla y separa en camaras para ser reforzados individualmente de acuerdo al comportamiento de ambos participantes. Los modelos de aislamiento tambien se han usado por los teoricos del juego y los ecologistas conductuales para analizar como los sujetos eligen entre conductas individuales que representan opciones de cooperacion y desercion. Estudios de campo de coordinacion cooperativa en animales y humanos demuestran que las consecuencias por Si solas son insuficientes para explicar porque y como ocurre la cooperacion. Se ha mostrado que las conductas cooperativas y la distribucion de consecuencias surgen a partir de las influencias sociales durante la ejecuci6n asi como de una membrecia compartida en grupos sociales. En algunos casos, la cooperacion persiste cuando los participantes se benefician por igual o cuando Ia accion individual es mas remunerable. La investigacion se describe usando un modelo de laboratorio para estudiar las influencias sociales en la cooperacion. Pares de ratas de laboratorio son reforzadas por ir y venir en una camara compartida en la cual no se restringe la interaccion social y los pares tienen una latitud considerable en como la contingencia de reforzamiento debe ser satisfecha. Adicionalmente, se puede evocar una competencia sobre Ia ganancia si se presenta uno o dos reforzadores periodicamente. Los resultados se describen mostrando que en la camara el ir y venir coordinado es una conducta social sensible a la presencia y tipo de companero asi como a la contingencia de reforzamiento. Los pares difieren en los niveles de coordinacion y en el surgimiento de dimensiones asimetricas que incluyen roles, dominancia agresiva, y distribucion de ganancias. Tambien se presenta evidencia que indica que la cooperacion afecta a los participantes, modifica las preferencias entre opciones individuales y cooperativas e incrementa el consumo de reforzamiento posterior a la sesion.