cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of Availability of Transcatheter Aortic-Valve Implantation on Survival for all Patients With Severe Aortic Stenosis

Clinical outcomes for the overall severe aortic stenosis (AS) patient population are not well described because those medically managed are not included in procedural registries, and AS severity is not identifiable from administrative data. We aim to assess whether transcatheter aortic valve implantation (TAVI) availability has been associated with overall changes in survival for the whole AS patient population. This is important because patients with AS in real-world practice may differ from those included in randomized controlled trials, potentially attenuating the purported treatment efficacy estimated in trials. Classic severe AS patients (mean gradient ≥40 mmHg) were identified from an echocardiography database. Survival was defined as time since severe AS diagnosis until death. We first compared survival among all patients before and after TAVI availability in 2008. To further understand mechanism, we then assessed whether any survival changes were attributable to TAVI with extended Cox regression models comparing survival among TAVI, surgical aortic valve replacement, and medically managed patients. 3663 classic severe AS patients were included in the study. Median survival years for all patients were greater during the TAVI-era than Pre-TAVI-era (>11.5 vs 6.8, 5-year-HR = 0.8, time-varying effect p 11.5 vs 9.5, 5-year-HR = 0.7, time-varying effect p = 0.045). TAVI patients age 65 to 74 had the lowest risk of death compared to medically managed patients (HR = 0.2, 95% CI = [0.1, 0.3], p
Impacts of large-scale teleconnection indices on chill accumulation for specialty crops in California.

Abstract Although the impacts of teleconnection indices on climate metrics such as precipitation and temperature in California have been widely studied, less attention has been given to the impact on integrated climate indices such as chill accumulation. This study investigates the linkages between large-scale teleconnections and winter chill accumulation for specialty crops in California, which may enable more effective and dynamic adaptation to in-season climate variability. Three large-scale teleconnection indices were selected: Oceanic Nino Index (ONI), Pacific-North American teleconnection pattern (PNA), and Pacific Decadal Oscillation (PDO) index to assess their effects on chill accumulation. The Chill Hours Model and Dynamic Model are adopted to calculate chill accumulation in Chill Hours (CH) and Chill Portions (CP) from November to January. Three major crop-producing regions, including the Central Coast, Sacramento Valley, and San Joaquin Valley, are used as the focused regions. Our results suggest CP generally has a stronger response to teleconnection patterns than CH in California. The correlations between chill accumulation and teleconnections are generally weaker during the summer than other seasons, and significant correlation can be observed 2–10 months before the start of the chill accumulation period. Among the three teleconnection indices, ONI is most weakly correlated to chill accumulation in focused regions, while PDO shows the strongest positive correlation and explains up to 39% variability of CP. PNA presents the most widespread negative correlation with chill accumulation. When aggregated to different teleconnection modes, +3.6 above-average CP is expected during ONI positive mode; +2.3 above-average CP is expected during PDO positive mode, while +2.1 above-average CP is expected during PNA negative mode. This study provides insights on early-season chill prediction and feasible management and adaptation strategies, and the methodology presented here can be used to develop decision support tools of risk control for agricultural producers and policymakers.
Neural Network Model for Estimation of the Induced Electric Field during Transcranial Magnetic Stimulation

Transcranial Magnetic Stimulation (TMS) is a non-invasive neuromodulation technique with applications in brain mapping and effective neuronal connectivity. In its repetitive mode, it is used for the treatment of neurological and psychiatric disorders. It functions on the principle of electromagnetic induction, where generated magnetic fields (H-field) induce electric field (E-field) that stimulates the brain’s neurons. With TMS studies, accurate estimation of the induced E-field is usually necessary. However, this requires a lot of processes, including the three-dimensional head model generation from magnetic resonance images (MRI) using the SimNIBS software and finite element analysis to calculate the induced E-field. These processes are time-consuming and computationally expensive. Additionally, with each head model’s uniqueness, outcomes cannot be generalized across a particular population as the intensity of E-field is subject-specific. In this research, the authors develop deep convolutional neural network (deep CNN) models to determine the intensity of the induced E-field directly from the patient’s MRI scan and across different coil types. We trained CNN models from anatomically realistic head models and across 16 coil types to predict the induced E-field in the brain and scalp (E-Max brain and scalp), and the volume of stimulation of the brain and scalp (V-half brain and scalp) from T1-weighted MRI scans. Using a deep CNN model, the processing time for estimating the induced E-field is significantly reduced, which is helpful both to clinicians and researchers as the need to create subject-specific anatomical head structures is eliminated. Also, there will be no need for additional stimulation sessions with the different coil types for TMS patients as the deep CNN model can predict the outcome from each coil type. The other advantage of the deep CNN model is that the E-field from the different coil types can be compared simultaneously.
FDG PET/CT & Breast Cancer: Value of Fourth and Subsequent Post Therapy follow up scans for Patient Management

1498 Objectives To evaluate the accuracy and value of the fourth and subsequent post-therapy follow-up FDG-PET/CT scans in the clinical assessment of breast cancer. Methods The institutional review board approved this retrospective study. Ninety-two female patients with a total of 426 fourth and subsequent follow-up PET/CT scans were included. Patients were followed for a median of 23.7 months (range, 0.7-124.4) from the fourth follow-up PET/CT. The diagnostic accuracy of PET/CT, its impact on clinical assessment, patients’ management and survival outcome were established. Results Of the 426 follow-up PET/CT scans, 264 (62%) were interpreted as positive and 162 (38%) were interpreted as negative. The sensitivity, specificity, PPV, NPV and accuracy of the fourth and subsequent follow-up PET/CT scans were 97.7%, 98.1%, 98.8%, 96.3% and 97.9% respectively. Fourth and subsequent follow-up PET/CT were helpful in excluding tumor in 13.4% (39/292) of patients with clinical suspicion of recurrence and identifying suspected recurrence in 10.5% (14/134) of patients without prior clinical suspicion. A change in management was noted in 27.7% (81/292) of scan times when the scans were done with clinical suspicion of recurrence or therapy response and in 6.7% (9/134) of scan times when the scans were done without prior clinical suspicion. Overall survival differed significantly between patients with all negative follow-up scans (n=23) and those who had at least one positive follow-up scan (n=69) (Logrank P Conclusions The fourth and subsequent PET/CT scans performed after completion of primary treatment in breast cancer had high diagnostic accuracy and lead to change in management in 27.7% of scans when done with prior clinical suspicion and only in 6.7% when done without clinical suspicion or context.
AutoLisp: programming by example

Featuring more than 100 ready-to-run AutoLISP programs and utilities for AutoCAD users and programmers, this book provides a teach-by-example tutorial for learning how to write AutoCAD programs in AutoLISP, a complete toolbox of AutoLISP programs that readers can plug into their own work as they are or modify for their programming needs.
Epidemiology and Prevention of Infection in the Compromised Host

A useful approach to the study of infection in the immunocompromised host is to first consider what factors make such a patient a compromised host. Knowledge regarding the major compromising factors then allows one to focus on diagnostic, therapeutic and preventative measures specific for that patient’s specific infection risks. These dysfunctions of host-defense mechanisms or factors that predispose to infection are discussed together with the types of infections with which they are most commonly associated.
Euthyroid Range Reevaluation for Radioactive Iodine Uptake Test

A new radioactive iodine uptake euthyroid range with 131I was obtained at our institution. The thyroid status of 150 patients seen at this institution for RAIU tests was determined utilizing thyroid hormone levels. A mean and standard deviation (s.d.) of the RAIU was calculated on the 57 patients with normal hormone levels. Two s.ds. about the mean yielded a range of 3.0–37.4%. We established a new normal range of 10–35% with the previous normal range being 10–30%.
individual variation in sleep quality and duration is related to cerebral mu opioid receptor binding potential during tonic laboratory pain in healthy subjects.

Objective Although poor sleep is a consequence of pain, sleep disturbance reciprocally induces hyperalgesia and exacerbates clinical pain. Conceptual models of chronic pain implicate dysfunctional supraspinal pain processing mechanisms, mediated in part by endogenous opioid peptides. Our preliminary work indicates that sleep disruption impairs psychophysical measures of descending pain modulation, but few studies have investigated whether insufficient sleep may be associated with alterations in endogenous opioid systems. This preliminary, exploratory investigation sought to examine the relationship between sleep and functioning of the cerebral mu opioid system during the experience of pain in healthy participants. Subjects and Design Twelve healthy volunteers participated in a 90-minute positron emission tomography imaging scan using [11C]Carfentanil, a mu opioid receptors agonist. During the session, pain responses to a 10% topical capsaicin cream were continuously rated on a 0–100 scale. Participants also completed the Pittsburgh Sleep Quality Index (PSQI). Results Poor sleep quality (PSQI) was positively and significantly associated with greater binding potential (BP) in regions within the frontal lobes. In addition, sleep duration was negatively associated with BP in these areas as well as the temporal lobe and anterior cingulate. Conclusions These findings suggest that poor sleep quality and short sleep duration are associated with endogenous opioid activity in these brain regions during the application of a noxious stimulus. Elucidating the role of the endogenous opioid system in mediating some of the associations between sleep and pain could significantly improve our understanding of the pathophysiology of chronic pain and might advance clinical practice by suggesting interventions that could buffer the adverse effects of poor sleep on pain.
Electron transfer between cytochromes c from horse and Pseudomonas.

Abstract The rate of electron transfer between horse cytochrome c and Pseudomonas cytochrome c 551 has been examined by stopped flow spectrophotometry. Experiments were conducted at temperatures from 4.5 to 32.5° and ionic strengths from 0.03 to 0.32. The pH was maintained at 7.0 with 0.02 m potassium phosphate buffer. Comparative data were obtained for the reaction of cytochrome c with potassium ferricyanide under these conditions. Whereas the rate of the ferricyanide reaction varied with the ionic strength, but not the temperature, the reverse held true for the reaction between cytochrome c and cytochrome c 551. The latter process was insensitive to changes in the ionic strength, and exhibited an activation energy of 12 kcal per mole. The equilibrium constant was found to be 1 at all temperatures. At 4.5°, pH 7.0, and an ionic strength of 0.2, a second order rate constant of 1.57 ± 0.18 x 104 m-1 sec-1 was obtained. Although Pseudomonas cytochrome c 551 and horse cytochrome c differ markedly in primary structure, and are oppositely charged at neutral pH, the rate of electron transfer at 20° corresponds closely to that previously estimated from nuclear magnetic resonance data for the electron exchange reaction between horse ferri- and ferrocytochrome c at this temperature.
Time Synchronization in Heterogeneous Sensor Networks

Time synchronization is a critical component in many wireless sensor network applications. Although several synchronization protocols have recently been developed, they tend to break down when implemented on networks of heterogeneous devices consisting of different hardware components and operating systems, and communicate over different network media. In this paper, we present a methodology for time synchronization in heterogeneous sensor networks (HSNs). This includes synchronization between mote and PC networks, a communication pathway that is often used in sensor networks, but has received little attention with respect to time synchronization. In addition, we evaluate clock skew compensation methods including linear regression, exponential averaging, and phase-locked loops. Our HSN synchronization methodology has been implemented as a network service and tested on an experimental testbed. We show that a 6-hop heterogeneous sensor network can be synchronized with an accuracy on the order of microseconds.
EFFECT OF LIMING MATERIALS ON SOIL AVAILABLE NUTRIENTS, YIELD, AND GRADE DISTRIBUTION OF DOUBLE-CROPPED TOMATO AND CUCUMBER GROWN WITH PLASTICULTURE

For economical reasons, cucumber (Cucumis sativus L.) may be grown as a double crop after tomato (Lycopersicon esculentum Mill.). In this production system, plant nutrition may be limited for the second crop due to pH change or insufficient levels of calcium or magnesium. The objective of this 2-year field study was to compare the effects of selected liming materials on yield and grade distribution, and soil available nutrients of a tomato/cucumber double crop produced with plasticulture. Liming materials were compared to a control and a CaSO4 treatment based on the same neutralizing value as standard agricultural limestone. Supplemental N fertilization was provided by weekly injections at a rate of 7 kg/ha/week from ammonium nitrate (NH4NO3) or calcium nitrate [Ca(NO3)2]. Each year, soil samples were collected at the beginning of the study and after each crop to determine nutrient availability. All liming materials raised soil pH in 1998 and 1999 over the unlimed control, though not to the target level f...
Pedunculopontine tegmental nucleus-induced inhibition of muscle activity in the rat.

The connections of the pedunculopontine tegmental nucleus (PPN) have led us to propose that this structure mediates striatally induced inhibition of muscle activity by directing basal ganglia output to an inhibitory reticulospinal system (nucleus reticularis gigantocellularis and ventralis, nrGi-V). We conducted experiments in order to examine the effects of electrical stimulation of the PPN on the activity of selected neck and shoulder muscles. PPN stimulation at low rates (0.1 Hz) elicited bilateral muscle excitation. As the rate of stimulation was increased (e.g. to 10 Hz), less excitation was observed. Anodal DC current inactivation of the nrGi-V during concurrent 10 Hz PPN stimulation resulted in an augmentation of muscle activity above the levels observed during 10 Hz PPN stimulation alone. PPN stimulation (10 Hz) also profoundly inhibited cortically-induced muscle activity. Further support for our proposal stems from increased baseline activity (0.1 Hz PPN-induced excitation) in animals with ibotenic acid lesions of the PPN as compared to normal animals. Apparently, destruction of the PPN releases the musculature from tonic and/or phasic inhibition. A model is discussed which attempts to account for both the rate-dependent changes in excitation and the inhibition of cortically induced muscle activity.
Evaluation of Baltazor known geothermal resources area, Nevada

Abstract By virtue of the Geothermal Steam Act of 1970, the U.S. Geological Survey is required to appraise geothermal resources of the United States prior to competitive lease sales. This appraisal involves coordinated input from a variety of disciplines, starting with reconnaissance geology and geophysics. This paper describes how the results of several geophysical methods used in KGRA evaluation were interpreted by the authors, two geophysicists, involved with both the Evaluation Committee and the research program responsible for obtaining and interpreting the geophysical data to be used by the committee.
Hunting and Scavenging by Plio-Pleistocene Hominids: Nutritional Constraints, Archaeological Patterns, and Behavioural Implications

Abstract The subsistence activities and diet of ancient hominids are debated topics, and some researchers have recently questioned the view that meat was a significant dietary component of Plio-Pleistocene hominids. We examine the potential advantages and disadvantages of ungulate utilization by ancient hominids (e.g. Homo habilis and early Homo erectus) with regard to (a) human nutritional constraints, (b) seasonal variations in the physical condition of modern African ungulates, (c) the wild plant food potential of East African environments, and (d) the faunal record from Plio-Pleistocene sites such as FLK Zinjanthropus at Olduvai Gorge, Tanzania. The different lines of evidence suggest that the subsistence activities of early Homo probably included active, confrontational scavenging to obtain mostly intact carcasses of large animals and some opportunistic hunting of small animals, both of which yielded significant quantities of meat and fat that were an important source of calories, vitamins, and minerals. The possibility of consuming toxic amounts of protein could have been averted by emphasizing the consumption of organ meats and viscera at certain times of the year.
Fractured geothermal reservoir growth induced by heat extraction

Presentation des methodes de mesure (injection de traceur, observations geochimiques, mesure de microseismes) dont les donnees mettent en evidence la croissance du reservoir de Fenton Hill au cours de son exploitation (ie de l'extraction de chaleur). Analyse du mecanisme de croissance (a partir des memes donnees) afin d'en determiner les origines: contraintes thermiques et/ou pressurisation hydraulique soutenue, qui generent l'extension de la fracture
Accurate determination of surface coverage in migration-enhanced epitaxy of compound semiconductors

We describe a new and highly precise method for determining the surface coverage during epitaxial deposition of compound semiconductors, using migration enhanced epitaxy (MEE). By monitoring the MEE reflection high energy electron diffraction (RHEED) intensity and a simple simulation of RHEED oscillations, one can determine the surface coverage with an accuracy of much better than 0.01 monolayer per cycle of MEE growth. The simplicity of the method makes it practical and convenient for preparing heterostructures with well defined and well characterized interfaces. The specific results reported are for ZnSe and ZnTe, but the method applies equally well to other compound semiconductors in both the II-VI and the III-V families.
Study of 1/f noise in N-MOSFET's: Linear region

A modified McWhorter model has been developed to explain the mechanisms involved in the 1/f noise in n-channel metal-oxide, semiconductor field-effect transistors (MOSFET's). Under the assumption of an energy distribution of traps in the bandgap, an expression for the power spectral density of 1/f noise was derived for MOSFET's operating in the linear region. Experimentally, noise measurements were performed on short-channel enhancement-mode MOSFET's with gate widths of 100 µm, and varying gate lengths of 2 to 10 µm. It was found that noise power increased with increasing drain voltage or decreasing gate bias. Quantitative analyses have been done to compare the experimental results with the model calculations.
Effects of etoposide-induced blood-brain barrier disruption on brain water, intracranial pressure, and cerebral vasomotor tone

Abstract This study investigated the effects of hypertension and water loading on etoposide-induced, reversible blood-brain barrier disruption in a rat model. Twenty-nine animals were divided into four groups: group 1—intracarotid (i.c.) injection of saline followed in 1 h by 5 ml i.c. water; group 2—i.c. etoposide followed by i.c. water; group 3—i.c. saline followed by i.v. metaraminol to increase systemic blood pressure; group 4—i.c. etopside followed by i.v. metaraminol. Systemic blood pressure and intracranial pressure were monitored continuously. Evans blue staining of the brain was used as a monitor of blood-brain barrier disruption. Animals were killed 1 h after either aramine or water infusion, and the brains removed and inspected for the degree of disruption. After dehydration, brain water was calculated for each hemisphere. Two-thirds of the animals infused with etopside had evidence of barrier disruption, whereas none of the control animals infused with saline were disrupted. Neither control groups 1 or 3 showed significant change in intracranial pressure after water loading or augmentation of systemic blood pressure, respectively. Group 4 animals failed to demonstrate any significant change in intracranial pressure despite marked barrier disruption and acute hypertension (within the limits of normal autoregulation). A small but statistically significant increase in intracranial pressure was noted in group 2 animals with the greatest degree of barrier disruption. A significant increase in brain water was observed ipsilateral to etoposide infusion in only those animals with the most marked barrier disruption. These results indicate that etoposide-induced blood-brain barrier disruption caused significant increases in brain water without significant alteration of cerebral vasomotor tone or increases in intracranial pressure after water loading except in the most severe disruption. The classic untoward consequences of vasogenic edema were not encountered in the present model.
Tube Feeding in Dementia: How Incentives Undermine Health Care Quality and Patient Safety

For nursing home residents with advanced dementia, very little evidence is available to show clinical benefit from enteral tube feeding. Although no randomized clinical trials have been done, considerable evidence from studies of weaker design strongly suggest that tube feeding does not reduce the risks of death, aspiration pneumonia, pressure ulcers, other infections, or poor functional outcome. Nationally, however, utilization is high and highly variable. System-wide incentives favor use of tube feeding, and may influence substitute decision-makers, bedside clinicians, gastroenterologists, and administrators regardless of patient preferences or putative medical indications. Underlying the widespread use of this marginally effective therapy is a basic misunderstanding about malnutrition and about aspiration pneumonia. The face value of tube feeding is strong indeed. In addition to the general faith in intervention, the impulse to "do something" when things are going poorly, financial incentives favor tube feeding for gastroenterologists, hospitals, and nursing homes. The desire to avoid regulatory sanctions, bad publicity, and liability exposure creates a further incentive for nursing homes to provide tube feeding. Rational, evidence-based use of tube feeding in advanced dementia will depend fundamentally on improved education. Reimbursement schemes require significant modification to limit the irrational use of tube feeding. Nursing home regulations based more securely on scientific evidence would likely reduce nonbeneficial tube feeding, as would evidence-based tort reform. Quality improvement initiatives could create positive incentives. Realigning incentives in these ways could, we believe, improve the quality of care, quality of life, and safety of these vulnerable individuals, likely with reduced costs of care.
Single crystal structure study of α-Ag2HgI4: Evidence for anharmonic vibration

Abstract X-ray diffraction intensities have been measured for two single crystals of α-Ag 2 HgI 4 at 66°C using Mo Kα radiation monochromated by reflection from a 002 graphite face. It is found that improvement on the simple zincblende description could be made either by considering all ions to be displaced by about 0.25 A along tetrahedral directions or by applying existing anharmonic theory for thermal motions. Although all ions are on appropriate sites to contribute to anharmonic effects, only a single anharmonic parameter, representing a weighted difference of two individual parameters, could be evaluated. The anharmonic treatment gives substantially better agreement for critical reflections of the class h + k + l = 4 n ± 1.
LocJam: a novel jamming-based approach to secure localization in wireless networks

Location discovery is an essential service in modern wireless consumer devices such as smartphones and mobile PCs. Existing anchor or base station-based positioning systems work well in non-hostile scenarios, but their accuracy suffers in the presence of cheating anchors. Securing location discovery in these positioning systems is an important, and still open, research problem. Earlier research efforts in this direction have mainly focused on either efficient detection and elimination of cheating anchors or on localization in the presence of cheating anchors. Proposals on localization in the presence of cheating anchors fail to perform well in the presence of a large number of cheating anchors, whereas, the issue of elimination of cheating anchors (once detected) has not been clearly addressed in techniques that focus on detection and elimination of cheating anchors. In this paper, we present a novel and deterministic strategy for securing anchor-based location discovery. Our technique employs a novel CDMA-based jamming strategy to eliminate (the effect of) cheating anchors during localization. We validate the performance of our proposal under various adversarial strengths and operating scenarios by means of extensive simulations.
A Fully Implicit Hybrid Solution Method for a Two-Phase Thermal-Hydraulic Model

We present a hybrid solution algorithm for the two-phase flow equations coupled to wall heat conduction. The partial differential equations in the physical model are the same as in RELAP5. The hybrid solution algorithm couples two solution methods, the solution method currently employed by RELAP5 and an implicitly balanced solution method. The resulting hybrid solution method is both fast and accurate. Results will be presented that show when accuracy and CPU time are considered simultaneously that there are ranges when the hybrid solution algorithm is preferred over the RELAP5 solution method.
Extending the product family approach to support safe reuse

Abstract Upcoming spacecraft will reuse software components to the extent that some systems will form product families of similar or identical units (e.g., a fleet of spaceborne telescopes). Missions such as these must be demonstrably safe, but the consequences of broad reuse are hard to evaluate from a software safety perspective. This paper reports experience specifying an interferometer (telescope) subsystem as a product family and supplementing the specification with results from a failure analysis. Extensions to the product family approach, with lessons learned, are discussed in three areas: (1) integration of safety analysis with the product family approach; (2) modeling decisions that have safety implications (e.g., how to handle near-commonalities, establishing a hierarchy of variabilities, and specifying dependencies among options); and (3) use of the product family requirements for design evaluation of reusable components as well as a specific product.
A review of techniques for processing ultra-high modulus polymers

Linear crystalline polymers can be processed to high degrees of orientation sufficient to produce dramatic increases in tensile strength and modulus. Three processes have been identified for inducing such orientation: cold drawing, hydrostatic extrusion, and solution spinning. All three processes utilize a high elongational velocity gradient in a critical temperature range to produce a high strength crystalline morphology. Although the molecular superstructure may differ in each case, the mechanical properties are similar, An increase in strength is achieved either through the creation of new tie molecules between crystal lamellae or through the creation of an extended chain crystal substructure. Temperature and molecular weight are the prime variables in determining which morphology will develop. The optimum processing temperature for many of the specific techniques is the crystalline dispersion temperature. At this temperature, the crystal structure is particularly adaptable to forming a new crystal morphology. Ul-tradrawn polymers are more Hookean in behavior than isotropic polymers and have properties similar to steel and glass. Polyoxymethylene has been processed most closely to its theoretical strength. Polyethylene, which is the most difficult to process, has achieved the highest modulus of any common polyolefin polymer, about 7 × 1010 Pa.
Lost in translation: Centripetal individualism and the classical concept of descending representation

The article argues that by the 17th century, despite the increased intellectual exchanges of the time, two different kind of individualism were developing across the Channel — one labeled here as ‘centripetal’, the other one as ‘centrifugal’. On the French side, one witnesses a focus on forum internum, as the only site of uniqueness and authenticity. On the British side, the emphasis switched to forum externum and the equality of wills. The article explores the consequences of these different self-apprehensions of the individual in terms of different understandings of political representation. I claim that, despite today’s general consensus, representing ‘the people’ was not naturally assimilated with an ascending theory of representation. ‘The people’, understood as a whole, was apprehended in France as still higher than its representatives — kings, Estates, or Parlements. The idea of individuals willingly delegating their rights and/or authority to a representative remained for more than a century a pec...
A purge and trap gas chromatographic method for dimethyl sulfide in freshwater

Abstract A simple purge and trap method is described for extracting trace levels (ng. 1−1) of dimethyl sulfide (DMS) in freshwater samples. The DMS extracted is determined in a gas chromatograph equipped with a dual-flame photometric detector and a 2-m Chromosil 330 Teflon column. Good recoveries (93-105%) are achieved when diethyl sulfide is used as an internal standard. The standard error of the mean (for replicates) is about 5% at low (8–10ng. 1l−1) DMS concentrations and about 3% at higher (90–130ng. 1−1) concentrations. The detection limit for the method is about 0.8ng. 1−1DMS. Water samples containing DMS should not be stored even at low temperature for more than 6 hours, but once extracted, the DMS may be preserved in the gas sample vials for weeks. The method has been used in determining the natural levels of DMS in surface waters from Hamilton Harbour (Lake Ontario). The values found between April and July, 1986 typically varied from 40 to 770ng. 1−1, and were much lower then the levels generally...
Compilation of data-driven programs for synchronous execution

We present algorithms that convert a class of parallel programs, called loop programs, from data-driven mode to synchronous mode. Such algorithms enable programmers to use a high-level, data-driven programming language without forfeiting the efficiency of a synchronous machine. We characterize loop programs for which conversion is possible in terms of sets of balancing equations and we present two conversion algorithms.
Control of gonadotropin secretion by follicle-stimulating hormone-releasing factor, luteinizing hormone-releasing hormone, and leptin

Abstract Fractionation of hypothalamic extracts on a Sephadex G-25 column separates follicle-stimulating hormone-releasing factor (FSHRF) from luteinizing hormone-releasing hormone (LHRH). The FSH-releasing peak contained immunoreactive lamprey gonadotropin-releasing hormone (lGnRH) by radioimmunoassay, and its activity was inactivated by an antiserum specific to lGnRH. The identity of lGnRH-III with FSHRF is supported by studies with over 40 GnRH analogs that revealed that this is the sole analog with preferential FSH-releasing activity. Selective activity appears to require amino acids 5–8 of lGnRH-III. Chicken GnRH-II has slight selective FSH-releasing activity. Using a specific lGnRH-III antiserum, a population of lGnRH-III neurons was visualized in the dorsal and ventral preoptic area with axons projecting to the median eminence in areas shown previously to control FSH secretion based on lesion and stimulation studies. Some lGnRH-III neurons contained only this peptide, others also contained LHRH, and still others contained only LHRH. The differential pulsatile release of FSH and LH and their differential secretion at different times of the estrous cycle may be caused by differential secretion of FSHRF and LHRH. Both FSH and LHRH act by nitric oxide (NO) that generates cyclic guanosine monophosphate. lGnRH-III has very low affinity to the LHRH receptor. Biotinylated lGnRH-III (10 −9 M) labels 80% of FSH gonadotropes and is not displaced by LHRH, providing evidence for the existence of an FSHRF receptor. Leptin has equal potency as LHRH to release gonadotropins by NO. lGnRH-III specifically releases FSH, not only in rats but also in cows.
Obtaining Intended Weights When Combining Students' Scores

An instructor typically combines students' scores from several measures such as assignments and exams when assigning course grades. The relative weights intended for these scores are at least inferred and often stated explicitly by the instructor. This module describes how scores can be adjusted so that the intended weights are obtained. Techniques are discussed for two grading criteria: (a) grading students through comparison to others in the class and (b) grading students through comparison to predetermined levels of performance.
A Proactive Approach to Planning and Designing Highways in East Tennessee Karst

The East Tennessee landscape consists of varied topography that reflects the lithology and geologic structure of the area. Karst makes up a large part of the East Tennessee landscape and is very problematic in locating, designing, and constructing highways. Instead of a reactive approach to dealing with karst in highway planning, design, and construction, this paper proposes a proactive methodology that is needed in karst terrain. Types of karst problems include sinkholes, caves and karren, collapse incidents, and groundwater contamination. Typical reactive remedial measures used in correcting karst-related highway problems include bridging, drainage alteration, and relocation. Proactive concepts implemented by the Tennessee Department of Transportation include avoidance measures such as relocation of the roadway and drainage design methods including impervious lined drainage ditches and highway runoff filtering systems. Additional proactive drainage measures include the use of graded rock pads, overflow channels from sinkholes to free-draining areas, sinkhole opening improvement and protection, and curbs for embankment sections. Innovative and cost-effective remedial concepts for solving karst-related geotechnical problems include avoidance, using lined ditches and graded rock pads, and other bridging- and drainage-related concepts. Stringent land use and building codes for karst areas are required to ensure the success of karst-related remedial design concepts proposed for highways.
CAN YOUNG ADULTS BE INFLUENCED TO EAT HEALTHIER SNACKS: THE EFFECTS OF CHOICE AND NUTRITIONAL INFORMATION ON TASTE, SATISFACTION AND INTENT TO PURCHASE

Nutritional information allows customers to make an informed choice regarding food consumption, which may be related to higher satisfaction and product ratings. Researchers designed this study to evaluate the impact of choice and nutritional information on young adults' selection and ratings of a soy-based snack versus an identical snack prepared using a traditional recipe. Specific objectives were to compare selection, quality ratings, and intention to purchase ratings with and without choice and information on nutrients per serving associated with both products. Two hundred college students were presented with an opportunity to select and evaluate two different formulations of the same snack. The products were identical in appearance, but the soy-based snack had nutrient content lower in calories and fat and higher in protein, calcium, and fiber. Participants rated the sensory characteristics of their product of choice on a 7-pt Likert-type scale. They also noted whether they were willing to buy the snack in the future. Analysis of variance was used for data analysis. When no choice of snack or nutritional information was made available, students rated both snacks equally. When a choice but no information was supplied, except that one product was made with soy, the traditional snack was chosen more often. When choice and nutritional information was supplied, the food quality ratings and intention to purchase ratings of both snacks increased, and the soy-based snack was chosen over the traditional product at a significantly higher rate. Differential effects by gender were noted. Nutritional information as informed choice was positively related to customer satisfaction and made a difference in food selection. Implications for foodservice operations focus on point of sale signage that would allow customers, particularly young adults, the information by which to choose food items to meet their personal nutritional goals. This would be particularly pertinent in university food service and high school cafeteria settings serving children and young adults.
Regulation of insulin-like growth factor binding protein secretion by a murine mammary epithelial cell line.

Abstract The regulation of insulin-like growth factor binding protein (IGFBP) secretion by mammogenic and lactogenic hormones was investigated in a mouse mammary epithelial cell line (COMMA-D/MME). Cells were grown to confluency on plastic culture plates in serum-containing medium. The confluent cells were exposed to the hormonal treatments in serum-free medium for 6 days. Conditioned medium was collected on Days 5 and 6 and analyzed for IGFBPs by 125 I-labeled insulin-like growth factor (IGF)-II ligand blotting and quantified by densitometry. IGFBP data were expressed as absorbance units × millimeters (AUxmm) that were corrected for DNA per well. In basal serum-free media, the COMMA-D/MME cells secreted predominately IGFBP-3, but also some IGFBP-2. The mammogenic growth factors, IGF-I (13.3 nM) and epidermal growth factor (EGF; 1.7 nM), both stimulated DNA synthesis (P ≤ 0.05); however, their effects on IGFBP-3 secretion differed. IGF-I stimulated IGFBP-3 secretion whereas EGF was inhibitory. In addition, EGF inhibited IGFBP-2 secretion and IGF-I tended to increase it. No interaction was observed between IGF-I and EGF for any of the parameters measured. Three lactogenic hormones (insulin, 154 nM; prolactin, 4.3 nM; and cortisol, 1.4 μM) in all combinations were tested to determine their effects on IGFBP secretion. Insulin stimulated IGFBP-3 secretion and DNA synthesis, but had no effect on IGFBP-2 secretion. Cortisol inhibited IGFBP-3 secretion and DNA synthesis, but increased IGFBP-2 secretion. Prolactin had no effect on any of the parameters examined. In summary, the COMMA-D/MME cells secrete IGFBP-2 and IGFBP-3 in serum-free media. Although the secretion of IGFBP-2 and IGFBP-3 was regulated by several of the hormones and growth factors tested, no clear distinction was observed between the mammogenic and lactogenic treatments.
Selective chemical modification of arginine residues in mitochondrial malate dehydrogenase

Mitochondrial malate dehydrogenase (L-malate: NAD+ oxidoreductase, EC 1.1.1.37) from porcine heart exhibits a time dependent loss in enzymatic activity in the presence of the reagent butanedione. The inhibition occurs concomitant with the modification of 2.4 residues of arginine per molecular weight of 70,000. The presence of the reduced coenzyme, NADH, protects the enzyme from inhibition by butanedione and from modification of arginine residues, suggesting that the residues modified are located near the coenzyme binding site and hence at or near the enzymatic active center of this enzyme.
Theoretical and experimental study of optical gain, refractive index change, and linewidth enhancement factor of p-doped quantum-dot lasers

A theoretical and experimental study of the optical gain, refractive index change, and linewidth enhancement factor (LEF) of a p-doped quantum-dot (QD) laser is reported. These parameters are measured by injecting an external pump, which induces cross-gain and cross-phase modulation. A comprehensive theoretical model for the optical gain and refractive index change of InAs QD lasers is introduced with the quasi-equilibrium approximation of carrier distribution. We use the Gaussian lineshape function for gain change and the confluent hypergeometric function of the first kind for refractive index change, which satisfies the Kramers-Kronig relation. We match the experimental data with the theoretical results when the thermal effect is isolated by an additional pulsed current measurement. We also calculate theoretically the optical gain, refractive index change, and LEF of an undoped QD laser of the same structure except the absence of p-type doping. We show that the differential gain and LEF of the p-doped QD laser are improved compared with those of the undoped QD laser due to the reduced transparency carrier density
Inhibition of respiration in plant tissues by callus stimulating substances and related chemicals.

Cytological studies of nine species of Lonchocarpus and four species of Derris reveal only one variant from 2n 22, L. utilis with 2n 44. Sterility in L. utilis, L. cyanescens, and D. elliptica is probably in each case a clonal rather than species mutation and has been preserved by cultivation. Rotenone production in Lonchocarpus apparently increases with polyploidy. No correlation has yet been discovered in Derris. The value of further genetical and cytological exploration to the development of commercial rotenone is pointed out.
Insulin is a prandial satiety hormone

The present study assessed meal-contingent insulin effects on spontaneous meal patterns. Rats, trained to lever press for daily food requirements, showed stable meal patterns and were then implanted with hepatic-portal catheters. Once again stable in ingestion, animals received either physiological saline or vehicle plus 1 or 2 mU of regular, short-acting insulin beginning at 10 pellets into each initiated meal (which was the chosen minimum meal size definition). All meals during that day were then infused with the same solution and comparisons were made within animals (across days) only. Insulin reduced the size of spontaneous meals at both 1 mU (p < .01) and 2 mU doses (p < .001). No other meal parameters were significantly affected. In a complementary study, rats trained to lever press showed increases in meal size when "recovering from" a diazeoxide-adulterated diet (diazeoxide has been shown to limit insulin release). Thus, when insulin is increased during spontaneously taken meals, those meals are reduced in size and drugs which block insulin release, increase the size of meals; we assert insulin is a prandial satiety hormone which likely reduced feeding by increasing glucose uptake into peripheral tissue.
Ipsilateral Proximal Femur and Shaft Fractures Treated With Hip Screws and a Reamed Retrograde Intramedullary Nail

Background Although not common, proximal femoral fractures associated with ipsilateral shaft fractures present a difficult management problem. A variety of surgical options have been employed with varying results.
Transepithelial Na+ transport and the intracellular fluids: a computer study.

Computer simulations of tight epithelia under three experimental conditions have been carried out, using the rheogenic nonlinear model of Lew, Ferreira and Moura (Proc. Roy. Soc. London. B 206:53–83, 1979) based largely on the formulation of Koefoed-Johnsen and Ussing (Acta Physiol. Scand.42:298–308, 1958). First, analysis of the transition between the short-circuited and open-circuited states has indicated that (i) apical Cl− permeability is a critical parameter requiring experimental definition in order to analyze cell volume regulation, and (ii) contrary to certain experimental reports, intracellular Na+ concentration (c Na c ) is expected to be a strong function of transepithelial clamping voltage. Second, analysis of the effects of lowering serosal K+ concentration (c K s ) indicates that the basic model cannot simulate several well-documented observations; these defects can be overcome, at least qualitatively, by modifying the model to take account of the negative feedback interaction likely to exist between the apical Na+ permeability andc Na c . Third, analysis of the effects induced by lowering mucosal Na+ concentration (c Na m ) strongly supports the concept that osmotically induced permeability changes in the apical intercellular junctions play a physiological role in conserving the body's stores of NaCl. The analyses also demonstrate that the importance of Na+ entry across the basolateral membrane is strongly dependent upon transepithelial potential,c Na m andc K s ; under certain conditions, net Na+ entry could be appreciably greater across the basolateral than across the apical membrane.
Two-gluino bound states

We estimate the branching ratio and argue that two-gluino bound states can be detected in UPSILON..--> gamma..+ /sup 1/S/sub 0/(gg) if m/sub g/<4.5 GeV. The signal would be comparable to the backgrounds in magnitude. In the case of top-quarkonium decay, the signal could be much enhanced due to the exchange of a possibly light scalar top quark. We also show that two-gluino bound states can exist only in /sup 1/S/sub 0/, /sup 3/P/sub 0,1,2/, /sup 1/D/sub 2/, /sup 3/F/sub 2,3,4/,..., but not in /sup 3/S/sub 1/, /sup 1/P/sub 1/, /sup 3/D/sub 1,2,3/, /sup 1/F/sub 3/,. . . states. The decay width of the gg ground state is calculated. Finally, we discuss the gg potential.
Separation and HPLC analysis of diastereomers and rotational isomers of L-N-(butyloxycarbonyl)-3-(3-hydroxyethyl-4-(benzyloxy)-phenyl) alanine benzyl ester

Abstract We have synthesized intermediates towards the preparation of a dimeric derivative of L‐dopa for the potential treatment of Parkinson's disease. We synthesized L‐N‐(butyloxycarbonyl)‐3‐(3‐hydroxy‐ethyl‐4‐(benzyloxy)‐phenyl)alanine benzylester, a compound containing a secondary alcohol moiety that has a unique set of characteristics. Upon reduction of the precursor, which contained a ketone moiety, we synthesized a material that when formed, contained a pair of diastereomers of the secondary alcohol, each diastereomer also exhibiting two individually stable conformational isomers. We believe that the conformational isomers were generated by rotation of the C‐N bond of the BOC carbamate, and were so stable that they could be separated by normal phase HPLC techniques. Energy optimization studies and molecular modeling techniques were performed using HyperChem, and rotational barrier energy values were calculated for the different conformational isomers for each of the diastereomers. HPLC and NMR tech...