cssi/SciSciGPT-SciSciNet huggingface dataset:
Sigma: a fault-tolerant mutual exclusion algorithm in dynamic distributed systems subject to process crashes and memory losses

This paper introduces the Sigma algorithm that solves fault-tolerant mutual exclusion problem in dynamic systems where the set of processes may be large and change dynamically, processes may crash, and the recovery or replacement of crashed processes may lose all state information (memory losses). Sigma algorithm includes new messaging mechanisms to tolerate process crashes and memory losses. It does not require any extra cost for process recovery. The paper also shows that the threshold used by the Sigma algorithm is necessary for systems with process crashes and memory losses.
Towards a mechanistic understanding of the synergistic effects of harvesting timber and non-timber forest products

Summary Classic theories of resource harvest assume logistic growth and incorporate harvest through an additional loss term. This methodology has been applied successfully in forest products harvesting such as timber logging. However, modelling harvest through a loss term is not appropriate for non-timber forest products (NTFP) since harvesting in this case does not always require the complete removal of individual plants. Empirical evidence suggest that NTFP harvest affects plant population growth rates. Additionally, timber and NTFP harvest can have synergistic effects on population dynamics. We develop and analyse a simple model that incorporates non-lethal harvest implicitly through the population growth rate of plants and lethal harvest explicitly through permanent removal of whole plants, with additional synergistic effects on population growth rate. To capture transient dynamics, we model the growth rate of plants explicitly as a dynamic variable affected by harvesting. Transient dynamics results indicate that populations have delayed response to discrete harvesting. We demonstrate exactly how the sustainability of lethal harvest, non-lethal harvest or both types of harvests depends on the demographic effect of each type of harvest on the population growth rate. Finally, we identify a threshold parameter , such that combined lethal and non-lethal harvest results in plant population sustainability when 1 and extinction when 1.
A Qualitative Evaluation of Behavior during Conflict with an Authoritative Virtual Human

This research explores the extent to which humans behave realistically during conflict with a virtual human occupying a position of authority. To this end, we created a virtual team to train nurses how to manage conflict in the operating room; the team’s virtual surgeon engages in reckless behavior that could endanger the safety of the team’s patient, requiring nurses to intervene and correct the virtual surgeon’s behavior. Results from post-hoc behavioral analysis and semi-structured interviews indicate that participants behaved realistically during conflict, as compared against existing behavioral frameworks. However, some participants reported perceiving their virtual teammates as strangers, which they felt may have caused them to behave differently than they would with their normal teammates.
Tolerance to maternal skin grafts in rabbits induced by hyaluronidase.

VASCULARIZED transplants are permanently successful only between identical twins or within a highly inbred strain. Even homografts from the mother to her litter are destroyed by the immunological process initiated by her transplant antigens1. However, tolerance for individual specific transplant antigens can be produced by the direct injection of donor cells into the fœtal or neo-natal animal1. These offspring accept grafts of normal tissue from the antigen donor. In contrast, uninjected control animals reject similar homologous transplants.
Fluorescent labeling of endothelial cells allows in vivo, continuous characterization of the vascular development of Xenopus laevis

Appropriate blood supply and vascular development are necessary in development and in cancer, heart disease, and diabetes. Here, we report the use of DiI-labeled acetylated low-density lipoprotein (DiI-Ac-LDL) to label endothelial cells and characterize the vasculature of live Xenopus embryos. The atlas we have created provides a detailed map of normal vascular development against which perturbations of normal patterning can be compared. By following the development of the intersomitic vessels in real-time, we show that, while rostrocaudal gradient of maturing intersomitic vessels occurs, it is not absolute. In addition, the comparative study of the ontogeny of nerve bundles from the spinal cord of transgenic Xenopus embryos expressing green fluorescent protein in the nervous system and blood vessels demonstrates a strong anatomical correlation in neurovascular development. These studies provide the basis for understanding how the vascular system forms and assumes its complicated stereotypical pattern in normal development and in disease.
Purchasing behavior of tourists towards Tennessee-made products.

Purchasing behaviors of tourists for Tennessee-made food products were examined. Amount of units purchased, approximate expenditures, and where products were purchased were recorded. Over 95% of the individuals purchased Tennessee-made food products for themselves and 64% purchased the products as gifts. The majority of the products were purchased at speciality stores or tourist sites. Products most often purchased included candies/confections and chocolates. Quality of the products was the most important factor in the decision to purchase. The average tourist visiting Tennessee purchased 4.9 items and spent $34.60 on these products. Processors of state-made products and tourism departments need to market the quality and uniqueness of their products at speciality shops and tourist sites.
The effects of CS and US intensity on shuttlebox avoidance

The effects of CS intensity (70-, 80-, or 90-dB white noise) and US intensity (0.3- or 1.3-mA shock) on acquisition of shuttlebox avoidance were evaluated in a 2 × 3 complete factorial design. Acquisition was inversely related to US intensity. CS intensity was positively related to acquisition at the high US intensity but had no effect at the low US intensity. Intense CS may facilitate acquisition at high US intensities because they disrupt the incompatible response of freezing which occurs with high shock levels.
Wind Tunnel Evaluation of Drift Reduction Potential and Spray Characteristics with Drift Retardants at High Operating Pressure

Although considerable research has been done on effectiveness of drift retardants for many years, answers to some questions are still unclear to applicators. Laboratory tests were conducted to evaluate drift potentials associated with off-target ground and airborne spray deposits discharged with a hollow cone nozzle spraying three different drift retardants at a high operating pressure and various wind velocities in a wind tunnel. Droplet sizes and spray widths were also determined with a laser imaging system and a portable spray patternator. At 1655 kPa pressure and 4.65 L/m flow rate, the volume median diameters of droplets from the hollow cone nozzle discharging spray mixtures containing water only, polyvinyl polymer, nonionic colloidal polymer and polyacrylamide polymer drift retardants were 201, 222, 239, and 210 μm, respectively. The major spray pattern width was not changed after drift retardants were added into the spray carrier. For the wind velocity from 1 to 5 m/s in the wind tunnel, the polyacrylamide drift retardant produced the highest airborne deposit among the three drift retardants, followed by polyvinyl, and then nonionic colloidal. Also, the polyacrylamide drift retardant produced the highest ground drift potential, followed by nonionic colloidal and then polyvinyl. According to the results from this laboratory study, both nonionic colloidal and polyvinyl polymer drift retardants reduced the drift potential compared to the spray carrier containing water only.
SINGLE-TRIAL AVOIDANCE CONDITIONING IN RATS

St~mnary.-Two experiments were designed to investigate shock intensity (current level), and shcck duration as variables in the conditioning of an avoidance response in ran wirh a single training trial. In Exp. 3, a fixed current and duration were used and the resistance of the established conditioned response to extinction was determined. A grid scrambled 3-ma., l-sec. shock applied to the four paws as a reinforcement was found to be most efficient in producing a high incidence and magnitude of conditioned avoidance. Training-testing intervals of 1 and 24 hr. yi-lded comparable results. increasing the duration of a 3-ma. shock reinforcement increased the resistance of the CR to extinction. Several techniques for establishing a conditioned avoidance response with a single punishing shock in a single trial have been reported. Hudson (1950)
The interpersonal structure of decision making: A social comparison approach to organizational choice☆

Abstract Under what circumstances does social information affect choices? A recent test of social information processing theory showed little effect of anonymous social cues on choices of brief tasks ( Kilduff & Regan, 1988 ). But from the perspective of social comparison theory ( Festinger, 1954 ) people faced with important and ambiguous decisions, such as the choice of an organization to work for, are likely to make their choices in the context of what others perceived to be similar to themselves are doing. For a cohort of MBA students, the relationships between patterns of social ties and patterns of interviews with recruiting organizations were analyzed. The results showed that students who perceived each other as similar, or who considered each other to be personal friends, tended to interview with the same organizations. These correlations remained significant even controlling for similarities in job preferences and similarities in academic concentrations. The research places the individual decision maker in a social context often ignored by normative approaches such as expectancy theory.
The effect of temperature on embryo survival and development in pallid sturgeon Scaphirhynchus albus (Forbes & Richardson 1905) and shovelnose sturgeon S. platorynchus (Rafinesque, 1820)

Summary The thermal response of pallid sturgeon Scaphirhynchus albus and shovelnose sturgeon S. platorynchus embryos was determined at incubation temperatures from 8 to 26°C and 8 to 28°C, respectively. The upper and lower temperatures with 100% (LT100) embryo mortality were 8 and 26°C for pallid sturgeon and 8 and 28°C for shovelnose sturgeon. It was concluded that 12–24°C is the approximate thermal niche for embryos of both species. Generalized additive and additive-mixed models were used to analyze survival, developmental rate and dry weight data, and predict an optimal temperature for embryo incubation. Pallid sturgeon and shovelnose sturgeon embryo survival rates were different in intermediate and extreme temperatures. The estimated optimal temperature for embryo survival was 17–18°C for both species. A significant interaction between rate of development and temperature was found in each species. No evidence was found for a difference in timing of blastopore, neural tube closure, or formation of an S-shaped heart between species at similar temperatures. The estimated effects of temperature on developmental rate ranged from linear to exponential shapes. The relationship for rate of development to temperature was relatively linear from 12°C to 20°C and increasingly curvilinear at temperatures exceeding 20°C, suggesting an optimal temperature near 20°C. Though significant differences in mean dry weights between species were observed, both predicted maximum weights occurred at approximately 18°C, suggesting a temperature optimum near 18°C for metabolic processes. Using thermal optimums and tolerances of embryos as a proxy to estimate spawning distributions of adults in a river with a naturally vernalized thermal regime, it is predicted that pallid sturgeon and shovelnose sturgeon spawn in the wild from 12°C to 24°C, with mass spawning likely occurring from 16°C to 20°C and with fewer individuals spawning from 12 to 15°C and 21 to 24°C. Hypolimnetic releases from Missouri River dams were examined; it was concluded that the cooler water has the potential to inhibit and delay sturgeon spawning and impede embryo incubation in areas downstream of the dams. Further investigations into this area, including potential mitigative solutions, are warranted.
Metabolic syndrome is associated with visit-to-visit systolic blood pressure variability in the US adults

Epidemiological studies have shown that blood pressure is not a constant variable. Evidence has accumulated showing that the blood pressure variability is associated with organ damage. A substantial increase in the prevalence of the metabolic syndrome has been documented globally. We examined the association of visit-to-visit blood pressure variability with the metabolic syndrome and its components, using data collected in the Third National Health and Nutrition Examination Survey. A multivariable generalized linear model was performed. The metabolic syndrome and its components, particularly hypertension, increased waist circumference and hyperglycemia, were significantly associated with systolic blood pressure variability across study visits (P 0.05). Additional research is required to verify the observed results in prospective studies and evaluate approaches to reduce blood pressure variability observed in clinical settings among persons with the metabolic syndrome to reduce its subsequent complications.
Speech-Language Pathology Assistants Current State of Affairs

Abstract The utilization of speech-language pathology assistants (SLPAs) is increasing in the United States particularly in the public schools. The American Speech-Language-Hearing Association prov...
BOVINE SERUM ALBUMIN IN LITHIUM CHLORIDE SOLUTIONS. III. A Comparative Study of Li+ and H3O+ Effects

The effects of Li+ and H3O+ on the conformation of bovine serum albumin in aqueous solutions at room temperature are compared. At low pH (high concentration of H3O+) the change in conformation of the protein is demonstrated by an increase in effective volume, a decrease in helical content and a blue shift of tyrosyl residue. A similar change is observed for the protein in highly concentrated LiCl solution (6.0–7.0 M) at neutral pH. However, the H3O+ is 12,000 times more powerful than the Li+ in destabilizing the protein molecule. This is consistent with their thermodynamic and kinetic properties, since the H3O+ is often different from the Li+ in several orders of magnitude. While the changes in structural properties of the protein are almost identical in both the acidic solution and the highly concentrated LiCl solution, further study using dioxane as a probe suggests different mechanisms under which the changes occur. The effect of H3O+ is related to electrostatic force, whereas the effect of Li+ is related to both the electrostatic and hydrophobic forces. These two major forces are believed to be responsible for the conformation of protein molecules.
Synthesis and characterization of the complete series of methylene-interrupted cis,cis-octadecadienoic acids

Abstract The complete series of methylene-interrupted cis,cis -octadecadienoic acids (analogues of linoleic acid), from the 2,5- to 14,17-isomer, has been synthesized. The 4,7- to 10,13-isomers were prepared by coupling a 1-bromoalk-2-yne with the di-Grignard complex of an (ˑ)-acetylenic acid and semi-hydrogenation of the resulting diynoic acid to a cis,cis -diene with Lindlar's catalyst. The 2,5- and 3,6-isomers and the 11,14- to 14,17-isomers were synthesized by first preparing the corresponding diacetylenic alcohols which were then oxidized to the acids and semi-hydrogenated. Purity of the intermediates and final compounds was established by gas-liquid and thin-layer chromatography. The compounds were characterized by melting points, critical solution temperatures, infrared spectroscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. Hydrogenation followed by gas chromatography confirmed the chain length and indicated absence of branched chain material. The positions of the double bonds were confirmed by ozonolysis. The 2,5-isomer has distinguishing features in its mass spectrum but only subtle distinctions can be detected in the spectra of the rest. The NMR spectra of the 2,5- to 5,8- and 11,14- to 14,17-isomers, however, all have features which uniquely identify them, though the 6,9- to 10,13-isomers have spectra which are virtually identical.
What's important in choosing a primary care physician: an analysis of consumer response

Given the growth of health maintenance organizations and preferred physician organizations, the purpose of this study was to determine the salient factors considered when choosing a primary care physician. A list of informational items about physicians not normally included in provider directories but which were indicated by the literature to be important were included in the survey instrument. Employees of a major state university in a south‐western state were surveyed. Results indicated that at the point of selection, the degree of patient satisfaction with the quality of care received and the accessibility of the physician were the two most relevant factors that impacted the choice of a physician. Other factors considered important included interpersonal skills and competence.
Segmentectomy Versus Wedge Resection for Non-Small Cell Lung Cancer in High-Risk Operable Patients

Background Patients with early-stage lung cancer and limited pulmonary reserve may not be appropriate candidates for lobectomy. In these situations, sublobar resection (wedge or segmentectomy) is generally performed. Many physicians believe that segmentectomy is superior because it allows for an improved parenchymal margin and nodal sampling. Methods We performed an analysis using operative and pathology reports collected as part of planned data collection for American College of Surgeons Surgical Oncology Group (ACOSG) Z4032. This was a prospective trial in which patients with clinical stage I lung cancer and limited pulmonary function were randomized to sublobar resection with or without brachytherapy. The operative approach (video-assisted thoracic surgery [VATS] vs thoracotomy), extent of resection, and degree of lymph node evaluation were at the discretion of the individual surgeon. The primary aim of this analysis was to compare the parenchymal margin achieved between segmentectomy and wedge resection. Secondary aims included the extent of nodal staging and whether the operative approach (VATS vs open) had an effect on margin status and nodal evaluation. Results Among 210 patients, 135 (64%) underwent a VATS approach and 75 (36%) a thoracotomy. A segmentectomy was performed in 57 patients (27%) and a wedge resection in 153 patients (73%). There were no significant differences in the degree of nodal upstaging, stations sampled, or parenchymal margin obtained between VATS and thoracotomy. However, significant differences were observed between patients who underwent a segmentectomy and those who underwent a wedge resection with regard to parenchymal margin (1.5 cm vs 0.8 cm, p = 0.0001), nodal upstaging (9% vs 1%, p = 0.006), and nodal stations sampled (3 vs 1, p p Conclusions In ACOSG Z4032, wedge resection, regardless of the approach, was associated with a smaller parenchymal margin and a lower yield of lymph nodes and rate of nodal upstaging when compared with segmentectomy.
Model catalyst studies with single crystals and epitaxial thin oxide films

Abstract The paper describes recent results from our relatively new program to perform detailed studies of the catalytic properties of metal-oxide materials; in particular, to effect a determination of the active catalytic site(s) and the mechanism for reactions over this especially important class of heterogeneous catalysts. Issues of structure-sensitivity, poisoning and promotion, and competing reaction mechanisms are critical questions that need to be addressed in a detailed manner for catalysis by oxides. As just one important example, both surface (Langmui–Hinshelwood) and direct (Eley–Rideal) reaction mechanisms have been proposed for the selective catalytic reduction (SCR) reaction of nitrogen oxides (NO x ) over vanadia/titania catalysts. For this program, we are using a number of unique, state-of-the-art capabilities available in the Environmental Molecular Sciences Laboratory (EMSL) at Pacific Northwest National Laboratory; for example, the first molecular beam epitaxy (MBE) system dedicated to the growth of model metal-oxide films, and a unique moderate-pressure catalytic reactor/surface science apparatus. We describe the growth, characterization, and water adsorption properties of a thin Fe 3 O 4 (0 0 1) film grown on a lattice-matched MgO(0 0 1) substrate. Because our moderate pressure catalysis studies are preliminary at this point, we instead describe our previous results on the CO oxidation reaction over a Ru(0 0 0 1) model catalyst to demonstrate the utility of the experimental approach. We specifically discuss the possibility that this reaction occurs by an Eley–Rideal mechanism.
Pitch angle scattering of cometary ions into monospherical and bispherical distributions

Low frequency magnetic fluctuations generated by solar wind/cometary ion distributions cause pitch-angle scattering of cometary ions. The nature of this pitch angle scattering is examined by means of one-dimensional hybrid simulations, in which newborn ions are created at a constant rate, and for various injection angles, alpha, relative to the magnetic field. Pitch angle scattering in the quasi-perpendicular regime (alpha above 60 deg) results in a bispherical velocity distribution while in the quasi-parallel regime (alpha between 0 and 60 deg), pitch angle scattering can result in either a monospherical or bispherical distribution, depending on the injection angle and initial beam velocity.
Enhanced Degradation and Soil Depth Effects on the Fate of Atrazine and Major Metabolites in Colorado and Mississippi Soils

The aim of this report is to inform modelers of the differences in atrazine fate between s-triazine-adapted and nonadapted soils as a function of depth in the profile and to recommend atrazine and metabolite input values for pesticide process submodules. The objectives of this study were to estimate the atrazine-mineralizing bacterial population, cumulative atrazine mineralization, atrazine persistence, and metabolite (desethylatrazine [DEA], deisopropylatrazine [DIA], and hydroxyatrazine [HA]) formation and degradation in Colorado and Mississippi s-triazine-adapted and nonadapted soils at three depths (0-5, 5-15, and 15-30 cm). Regardless of depth, the AMBP and cumulative atrazine mineralization was at least 3.8-fold higher in s-triazine-adapted than nonadapted soils. Atrazine half-life (T1/2) values pooled over nonadapted soils and depths approximated historic estimates (T1/2 = 60 d). Atrazine persistence in all depths of s-triazine-adapted soils was at least fourfold lower than that of the nonadapted soil. Atrazine metabolite concentrations were lower in s-triazine-adapted than in nonadapted soil by 35 d after incubation regardless of depth. Results indicate that (i) reasonable fate and transport modeling of atrazine will require identifying if soils are adapted to s-triazine herbicides. For example, our data confirm the 60-d T1/2 for atrazine in nonadapted soils, but a default input value of 6 d for atrazine is required for s-triazine adapted soils. (ii) Literature estimates for DEA, DIA, and HA T1/2 values in nonadapted soils are 52, 36, and 60 d, respectively, whereas our analysis indicates that reasonable T1/2 values for s-triazine-adapted soils are 10 d for DEA, 8 d for DIA, and 6 d for HA. (iii) An estimate for the relative distribution of DIA, DEA, and HA produced in nonadapted soils is 18, 72, and 10% of parent, respectively. In s-triazine-adapted soils, the values were 6, 23, and 71% for DIA, DEA, and HA, respectively. The effects of soil adaptation on metabolite distribution need to be confirmed in field experiments.
A protein with kinase and phosphatase activities involved in regulation of tricarboxylic acid cycle

Phosphorylation–dephosphorylation reactions as a form of regulatory control are assuming increasing importance in our understanding of cellular processes. The phosphorylation–dephosphorylation reaction was the first example of covalent modification in control and has been found to be present in almost every type of cellular process including synthesis of cell constituents, metabolic pathways and even gene expression1. It has assumed increasing importance as a result of the finding that some proteins coded for by carcinogenic viruses apparently are involved in a phosphorylation reaction2,3. To better understand the principles underlying these processes, we have studied the role of phosphorylation of isocitrate dehydrogenase (IDH) in the regulation of the branch point between the tricarboxylic acid (TCA) cycle and the glyoxylate bypass. We report here that in the process of purifying the kinase and phosphatase, we made two surprising observations—the kinase and phosphatase activities appear to be associated with the same protein, and the phosphatase activity has an absolute requirement for ATP.
Non-Destructive Characterization of Porous Silicon Using X-Ray Reflectivity

Understanding the evolution of porous silicon (PS) layers at the early stages of growth is important for determining the mechanism of PS film growth and controlling the film properties. We have used X-ray reflectivity (XRR) to determine the evolution of layer thickness and interfacial roughness during the growth of thin PS layers (< 200 nm) prepared by electrochemical anodization. The porous layer grows at a constant rate for films as thin as 15 nm indicating a very short incubation period during which the surface may be electropolished before the PS structure begins to form. Interface roughness measurements indicate that the top surface of the film remains relatively smooth during growth while the roughness of the PS/silicon interface increases only slightly with film thickness. The XRR results are compared with results obtained from the same films by cross-sectional transmission electron microscopy (XTEM), atomic force microscopy (AFM) and gravimetry.
The Role of Gallium-67 Scanning in the Clinical Staging and Preoperative Evaluation of Patients with Carcinoma of the Lung

Gallium-67 scanning was evaluated in 100 patients with proved carcinoma of the lung. It was valuable in separating primary from secondary lung tumors, determining the extent of contralateral hilar or mediastinal lymph node involvement, and detecting distant organ metastases. In addition to multiplane whole-body Ga-67 tomographic scanning, colloid liver scans, bone scans, and computerized axial tomography scans of the brain were obtained to determine the presence of distant metastasis. The gallium scan detected 11 of 12 occult metastases and identified 7 of 7 liver, 9 of 14 brain, 4 of 4 soft tissues, 1 of 4 contralateral lung, and 9 of 11 bone metastases. The whole-body gallium scan accurately detected or excluded extrathoracic metastatic disease in 11 of 12 patients examined postmortem within three months of a gallium scan. An approach is recommended using gallium scanning along with chest roentgenograms for clinical staging and preoperative evaluation of patients with carcinoma of the lung. Specific organ scans should be reserved for the occasional symptomatic patient with a negative gallium scan or for clarification of an indeterminate gallium scan.
Distribution of damage along an MeV ion track

It is well known that at low values or dE/dx the damage along the path or an ion in a dielectric solid is not uniform. This distribution or damaged regions versus ion type and energy provides the most direct path to understanding the mechanism that initiates the formation of the damage track. In this report I extract this distribution from recently published data on tracks in Y_3Fe_5O_(12) and compare it with extant data obtained for mica. It is found that these crystalline materials, for which the greatest amount of data exist, provide a virtually identical picture or the process. For such materials the energy loss or the ion is primarily to electronic excitation or the material and is typically in the keV/nm range.
Survey of potatoes grown in New York State for aldicarb residues.

Aldicarb [2-methyl-2-(methylthio)propionaldehyde O-(methylcarbamoyl)oxime] (Temik) is a broad-spectrum pesticide registered for use on a wide variety of agricultural crops. A single application, in the case of potatoes at the time of seed planting, protects the crop for the entire season against a variety of insects, mites, and nematodes. Upon weathering, aldicarb is oxidized to aldicarb sulfoxide and aldicarb sulfone (Kuhr and Dorough 1976). When field-grown potatoes were exposed to in-furrow treatment with aldicarb, the expected sulfoxidation products were found but no parent compound was extracted from any portion of the plants (Andrawes et al. 1971). The tolerance in the United States for residues of aldicarb and its metabolites in potatoes is i ppm (Code of Federal Regulations 1983). As part of the Food and Drug Administration's (FDA) ongoing pesticide residue surveillance program, the FDA Buffalo District conducted a survey of potatoes grown in New York State in 1982 to determine carbamate insecticide use and residue content after harvest. The residue of particular interest was aldicarb. This insecticide is systemic, its metabolites are stable, and its application to potatoes is recommended for a variety of insect pests. Due to the contamination of groundwater with aldicarb on Long Island, the manufacturer requested from the Environmental Protection Agency (EPA) an amendment to its product label banning the use of aldicarb in Suffolk County, NY. This was granted (Zaki et al. 1982). MATERIALS AND METHODS Fifty samples, representing potatoes grown in four areas of New York State, were collected. Interviews with growers were obtained for nearly all samples. With the exception of potatoes grown on Long Island, all growers indicated that granular aldicarb had been applied at rates between 13 and 20 lb/acre at planting. No further applications of aldicarb were made.
Lightweight scheduling for delay and bandwidth assurance in differentiated services

To overcome the inherent limitation of the single best- effort service currently provided the Internet, providing differentiated services for different classes of applications is being discussed in IETF. In this paper, we propose a lightweight packet scheduling algorithm that allocates forwarding resources to different classes, which we name controlled priority (CP) gateway algorithm. The proposed CP algorithm consists of two mechanisms denoted by CP-CQD (controllable queuing delay) and CP-STI (service time interval), respectively. CP-CQD controls the queuing delay for a class of delay/jitter-sensitive traffic. CP-STI is to service classes that require bandwidth assurance. The proposed algorithm can provide guaranteed bounds of delay, jitter, rate, and packet loss to certain aggregate flows. The CP-CQD can accommodate variable bit rate as well as constant bit rate flow without bandwidth reservation for end-to-end delay bound and minimum delay jitter. The CP-STI enables tagged classes to get guaranteed throughput. These two modules can control resources allocated to the traffic classes by adjusting parameters in response to local congestion level. The simulation results show that CP gateway algorithm can provide required quality of service to certain classes while easing the negative effects on best- effort classes.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A Heterogeneous Mixture of F-Series Prostaglandins Promotes Sperm Guidance in the Caenorhabditis elegans Reproductive Tract

The mechanisms that guide motile sperm through the female reproductive tract to oocytes are not well understood. We have shown that Caenorhabditis elegans oocytes synthesize sperm guiding F-series prostaglandins from polyunsaturated fatty acid (PUFA) precursors provided in yolk lipoprotein complexes. Here we use genetics and electrospray ionization tandem mass spectrometry to partially delineate F-series prostaglandin metabolism pathways. We show that omega-6 and omega-3 PUFAs, including arachidonic and eicosapentaenoic acids, are converted into more than 10 structurally related F-series prostaglandins, which function collectively and largely redundantly to promote sperm guidance. Disruption of omega-3 PUFA synthesis triggers compensatory up-regulation of prostaglandins derived from omega-6 PUFAs. C. elegans F-series prostaglandin synthesis involves biochemical mechanisms distinct from those in mammalian cyclooxygenase-dependent pathways, yet PGF2α stereoisomers are still synthesized. A comparison of F-series prostaglandins in C. elegans and mouse tissues reveals shared features. Finally, we show that a conserved cytochrome P450 enzyme, whose human homolog is implicated in Bietti's Crystalline Dystrophy, negatively regulates prostaglandin synthesis. These results support the model that multiple cyclooxygenase-independent prostaglandins function together to promote sperm motility important for fertilization. This cyclooxygenase-independent pathway for F-series synthesis may be conserved.
COMPARING DISPERSIVITIES AND SOIL CHLORIDE CONCENTRATIONS OF TURFGRASS-COVERED UNDISTURBED AND DISTURBED SOIL COLUMNS

Research relating to soil leaching properties under turfgrass conditions has often been conducted on disturbed soils where macropore structure has been destroyed. The objective of this study was to compare the solute movement characteristics of undisturbed and disturbed soil columns covered with turfgrass. Dispersivities and chloride (Cl) breakthrough curves of undisturbed and disturbed soils were investigated. Soil columns were excavated into three sections after testing, for which the mean bulk density was 1.33 Mg M−3 for the undisturbed columns and 1.16 Mg m−3 for the disturbed columns. The dispersivity for the undisturbed columns was over three times greater than for the disturbed columns. Chloride concentration found in Layer 1 (0–6.7 cm), Layer 2 (6.7–13.4 cm), and Layer 3 (13.4–20.0 cm) were 2.8, 5.3, and 4.8 times higher, respectively, for the disturbed soils than for the undisturbed. Applying conclusions from solute movement studies using repacked columns covered with turfgrass to actual undisturbed field conditions could lead to errors in interpretation because of the effect of macropores.
Loss and Recovery of Liver Regeneration in Rats with Fulminant Hepatic Failure

We earlier described a model of fulminant hepatic failure (FHF) in the rat where partial hepatectomy is combined with induction of right liver lobes necrosis. After this procedure, lack of regenerative response in the residual viable liver tissue (omental lobes) was associated with elevated plasma hepatocyte growth factor (HGF) and transforming growth factor beta (TGF-beta1) levels and delayed expression of HGF and c-met mRNA in the remnant liver. Here, we investigated whether syngeneic isolated hepatocytes transplanted in the spleen will prolong survival and facilitate liver regeneration in FHF rats. Inbred male Lewis rats were used. Group I rats (n = 46) received intrasplenic injection of 2 x 10(7) hepatocytes and 2 days later FHF was induced. Group II FHF rats (n = 46) received intrasplenic injection of saline. Rats undergoing partial hepatectomy of 68% (PH; n = 30) and a sham operation (SO; n = 30) served as controls. In 20 FHF rats (10 rats/group), survival time was determined. The remaining 72 FHF rats (36 rats/group) were used for physiologic studies (liver function and regeneration and plasma growth factor levels). In Group I rats survival was longer than that of Group II controls (73 +/- 22 hr vs. 33 +/- 9 hr; P < 0. 01). During the first 36 hr, Group I rats had lower blood ammonia, lactate, total bilirubin, PT, and PTT values, lower activity of liver enzymes, and higher monoethylglycinexylidide (MEGX) production than Group II rats. In Group I rats, livers increased in weight at a rate similar to that seen in PH controls and showed distinct mitotic and DNA synthetic activity (incorporation of bromodeoxyuridine and proliferation cell nuclear antigen expression). Plasma HGF and TGF-beta1 levels in these rats decreased and followed the pattern seen in PH rats; additionally, c-met expression in the remnant liver was accelerated. Hepatocyte transplantation prolonged survival in FHF rats and facilitated liver regeneration. Even though the remnant liver increased in weight four times reaching 30% of the original liver mass, the transplant-bearing rats expired due to inability of the regenerating liver to support the rat.
Phenobarbital N-glucosylation by human liver microsomes

Glucosylation of xenobiotics in mammals has been observed for a limited number of drugs. Generally, these glucoside conjugates are detected as urinary excretion products with limited information on their formation. An in vitro assay is described for measuring the formation of the phenobarbital N-glucoside diasteriomers ((5R)-PBG, (5S)-PBG) using human liver microsomes. Human livers (n=18) were screened for their ability to N-glucosylate PB. Cell viability, period of liver storage, prior drug exposure, serum bilirubin levels, age, sex and ethnicity did not appear to influence the specific activities associated with the formation of the PB N-glucosides. The average rate of formation for both PB N-glucoside was 1.42±1.04 (range 0.11–4.64) picomole/min/mg-protein with an (5S)-PBG/(5R)-PBG ratio of 6.75±1.34. The apparent kinetic constants, Km and Vmax, for PB N-glucosylation for eight of the livers ranged from 0.61–20.8 mM and 2.41–6.29 picomole/min/mg-protein, respectively. The apparent Vmax/Km ratio for PB exhibited a greater than 20 fold variation in the ability of the microsomes to form the PB N-glucosides. It would appear that the formation of these barbiturate N-glucoside conjugates in vitro are consistent with the amount of barbiturate N-glucosides formed and excreted in the urine in prior drug disposition studies.
Pituitary Glycoprotein Hormone α-Subunit Secretion after Thyrotropin-Releasing Hormone Stimulation in Normal Men and Men with Idiopathic Hypogonadotropic Hypogonadism*

Although TRH stimulates the release of uncombined α-subunit into the circulation in patients with primary hypothyroidism, it is not clear whether α-subunit is released from the thyrotrophs in euthyroid subjects. We hypothesized that spontaneous fluctuations in circulating α-subunit released from gonadotrophs by GnRH in normal adults could obscure the detection of small changes in α-subunit after TRH administration. We, therefore, examined α-subunit responses to TRH in five euthyroid men with idiopathic hypogonadotropic hypogon-adism (IHH), who produce little or no GnRH, five normal men, and four postmenopausal women. Mean (±sem) basal serum α-subunit levels were significantly (P < 0.05) less in men with IHH (0.26 ± 0.07 μg/L) than in the normal men (0.80 ± 0.20 μg/L) or postmenopausal women (3.54 ± 0.60 μg/L)- α-Subunit levels rose after TRH administration in all men with IHH to a peak level of 0.86 ± 0.25 ng/ml; TSH levels also increased from 1.9 ± 0.4 to 13.0 ± 5.6 mU/L. The increment in TSH and α-subun...
The Effects of Verbal Versus Photographic Self‐Presentation on Impression Formation in Facebook

Scholars of computer-mediated communication have long been interested in the way in which interpersonal impressions form among computer users. Early Internet research explored how people used text-based social information to form impressions of others. However, sociotechnological systems now allow users to present themselves in a variety of forms. The first study found that when textual and photographic cues were presented alone, the principle of textual primacy predicted results; however, Study 2 found when cues were presented together in the context of a Facebook profile, the data were consistent with a visual primacy—negativity perspective such that photographs more strongly influenced judgments of social orientation, and textual cues influenced social orientation judgments when accompanied by an introverted photograph.
Internal lattice relaxation of single-layer graphene under in-plane deformation

For noncentrosymmetric crystals, internal lattice relaxation must be considered for theoretical predictions of elastic properties. This paper develops a molecular dynamics approach for determination of the internal relaxation displacement in a single-layer graphene sheet under macroscopically homogeneous in-plane deformation. Based on an analytical interatomic potential, a generally nonlinear relationship between the internal relaxation displacement and the applied macroscopic strain is obtained explicitly from molecular dynamics simulations with a rhombic unit cell under finite deformation. A linear relationship is derived for relatively small strains, which can be conveniently incorporated into a continuum description of the elastic behavior of graphene. It is found that the internal relaxation has a strong effect on theoretical elastic moduli of graphene. In addition, the relationship between elastic properties for graphene and carbon nanotubes is discussed.
Activity and the Rotation Period of Comet Hyakutake (1996 B2)

Abstract Narrowband photometry of Comet Hyakutake (1996 B2) revealed periodic variability in the production of dust and gas during the comet's close approach to Earth in March 1996. The photometry alone was insufficient to unambiguously discriminate among several possible periods, but a unique period determination was possible by utilizing repeating morphological features in CCD images obtained simultaneously with the photometry on the nights of March 23–25. In particular, a large puff or blob of material was seen to be released in the sunward direction every 6.23 ± 0.03 h. This periodic release of material, presumably from a single dominant active region on the surface, was the source of the observed lightcurve variations. A second, much smaller morphological feature also repeats each cycle, confirming the value of 6.23 h for Hyakutake's synodic rotational period.
Uncertainty and the rise of the work-family dilemma.

Existing research argues that womens wages consumerism and changing attitudes dismantled the male bread-winner systems. Families economic need is dismissed with the suggestion that mothers rhetoric of "need" was a smoke screen to defend against social stigma for working mothers. Drawing on biennial data from 1965-87 the author suggests that consumptive certainty of the 1950s and the 1960s gave way to economic uncertainty in the 1970s and beyond. Economic uncertainty provided impetus legitimacy and justification for young families to adopt new work-family arrangements. Hence economic uncertainty is conceptualized as a real circumstance that substantiates families reasonable perceptions of need. (authors)
In situ inhibition of uterine activity by indomethacin: possible relevance to preterm labor prevention after fetal surgery.

Abstract Purpose This report is an analysis of the effects of local indomethacin delivery on uterine activity in vitro. Methods Isolated strips of time-dated pregnant rats' myometrium were placed within controlled tissue baths. Spontaneous muscular activity was recorded by a force transducer connected to a polygraph at cumulative concentrations of indomethacin. Statistical analysis was by single-factor analysis of variance (ANOVA), with P values of less than .05 considered significant. Results Within a narrow concentration range, the effects of indomethacin on frequency and amplitude of myometrial contractions were nonmonotonic, with an increase in frequency at levels that began to depress amplitude. However, both amplitude and frequency were significantly depressed and eventually totally abolished at most concentrations studied ( P Conclusions Indomethacin administered in situ consistently inhibits or completely arrests overall myometrial activity. The concept of local myometrial delivery of indomethacin, possibly via slow release systems, may prove clinically useful as an adjuvant to its systemic administration in preterm labor prevention after fetal surgery, warranting further trials in vivo.
Cranial neural crest recycle surface integrins in a substratum-dependent manner to promote rapid motility

Cell migration is essential for proper development of numerous structures derived from embryonic neural crest cells (NCCs). Although the migratory pathways of NCCs have been determined, the molecular mechanisms regulating NCC motility remain unclear. NCC migration is integrin dependent, and recent work has shown that surface expression levels of particular integrin α subunits are important determinants of NCC motility in vitro. Here, we provide evidence that rapid cranial NCC motility on laminin requires integrin recycling. NCCs showed both ligand- and receptor-specific integrin regulation in vitro. On laminin, NCCs accumulated internalized laminin but not fibronectin receptors over 20 min, whereas on fibronectin neither type of receptor accumulated internally beyond 2 min. Internalized laminin receptors colocalized with receptor recycling vesicles and were subsequently recycled back to the cell surface. Blocking receptor recycling with bafilomycin A inhibited NCC motility on laminin, indicating that substratum-dependent integrin recycling is essential for rapid cranial neural crest migration.
An Introductory Study in Center Push-Pull Ventilation

This report presents the results of a study on center push-pull ventilation for open surface tanks. The study was performed on a full-scale mock tank which had fixed dimensions. The objectives of the study were as follows: 1) to develop a curve for the minimum pull flow for a given push flow (called a match point curve); 2) to develop velocity profiles for one match point; and 3) to characterize the general airflow patterns for the system. The respective methods used for the objectives of the study were as follows: smoke, put into the push blower inlet, with visual observation; smoke tube traces and velocity measurements with a hot wire anemometer; and smoke tube traces. All three objectives of the study were accomplished and are presented in the report along with a discussion of the results. Some recommendations are also made for future research.
An Update on Emergency Contraception Use in Adolescents

Changing circumstances regarding access to emergency contraception (EC) warrant nurses' review of its current status. Nurses have the potential to improve adolescents' awareness of and access to EC so that adolescents may prevent pregnancy. Research suggests that adolescents lack awareness of EC methods that prevent pregnancy following an unprotected act of intercourse. Many pregnancies occurring in adolescence could be prevented with appropriate EC use. Studies show that adolescents are capable of using EC correctly and safely, and that access to EC is not associated with increased rates of unprotected intercourse or with higher rates of pregnancy or sexually transmitted infections.