cssi/SciSciGPT-SciSciNet huggingface dataset:
Biotreatment of chlorpyrifos in a bench scale bioreactor using Psychrobacter alimentarius T14

Bacteria tolerant to high pesticide concentration could be used for designing an efficient treatment technology. Bacterial strains T14 was isolated from pesticide-contaminated soil in mineral salt medium (MSM) and identified as Psychrobacter alimentarius T14 using 16S rRNA gene sequence analysis. Bench scale bioreactor was evaluated for biotreatment of high Chlorpyrifos (CP) concentration using P. alimentarius T14. Effect of various parameters on bioreactor performance was examined and optimum removal was observed at optical density (OD600 nm): 0.8; pH: 7.2; CP concentration: 300 mg L−1 and hydraulic retention time: 48 h. At optimum conditions, 70.3/79% of CP/chemical oxygen demand (COD) removal was achieved in batch bioreactors. In addition, P. alimentarius T14 achieved 95/91, 62.3/75, 69.8/64% CP/COD removal efficiency with addition of CS (co-substrates), CS1 (yeast extract + synthetic wastewater), CS2 (glucose + synthetic wastewater) and CS3 (yeast extract), respectively. Addition of CS1 to bioreactor ...
The New Thing

SHE ATTEMPTED, he urging her on, the new thing. The old thing had served them well, but they were tired of it, more than tired. Had the old thing ever been new? Perhaps, but not in their experience of it. For them, it was always the old thing, sometimes the good old thing, other times just the old thing, there like air or stones, part (so to speak) of the furniture of the world into which they had moved and from which, sooner or later, they would move out. It was not at first obvious to them that this world had
A Comparative Study of Ordering and Classification of Fault-ProneSoftware Modules

Software quality models can predict the quality of modules early enough for cost-effective prevention of problems. For example, software product and process metrics can be the basis for predicting reliability. Predicting the exact number of faults is often not necessary; classification models can identify fault-prone modules. However, such models require that ’’fault-prone‘‘ be defined before modeling, usually via a threshold. This may not be practical due to uncertain limits on the amount of reliability-improvement effort. In such cases, predicting the rank-order of modules is more useful. A module-order model predicts the rank-order of modules according to a quantitative quality factor, such as the number of faults. This paper demonstrates how module-order models can be used for classification, and compares them with statistical classification models. Two case studies of full-scale industrial software systems compared nonparametric discriminant analysis with module-order models. One case study examined a military command, control, and communications system. The other studied a large legacy telecommunications system. We found that module-order models give management more flexible reliability enhancement strategies than classification models, and in these case studies, yielded more accurate results than corresponding discriminant models.
CD8 T Cell Clonal Expansion and Development of Effector Function Require Prolonged Exposure to Antigen, Costimulation, and Signal 3 Cytokine

Full activation of naive CD8 T cells requires Ag, costimulation, and a third signal that can be provided by IL-12. Brief exposure (6 h) to Ag and B7-1 is sufficient to stimulate multiple rounds of cell division, but clonal expansion and development of effector function are minimal even when signal 3 is present. Full activation instead requires concerted signaling by Ag, B7-1, and IL-12 for greater than 40 h. Thus, the gene expression program required for cell division can be initiated by brief interaction with Ag and costimulation, but maintaining the expression of the genes needed for survival and effector function requires prolonged signaling by a signal 3 cytokine in concert with Ag and costimulation.
Restricted and unrestricted non-Hermitian Hartree-Fock: Theory, practical considerations, and applications to metastable molecular anions

This work describes the implementation and applications of non-Hermitian self-consistent field (NH-SCF) theory with complex basis functions for the ab initio computation of positions and widths of shape resonances in molecules. We utilize both the restricted open-shell and the previously unexplored spin-unrestricted variants to compute Siegert energies of several anionic shape resonances in small diatomic and polyatomic molecules including carbon tetrafluoride which has been the subject of several recent experimental studies. The computation of general molecular properties from a non-Hermitian wavefunction is discussed, and a density-based analysis is applied to the (2)B1 shape resonance in formaldehyde. Spin-unrestricted NH-SCF is used to compute a complex potential energy surface for the carbon monoxide anion which correctly describes dissociation.
A.C. thermal theory for temperature-sensitive semiconductors

The present investigation is concerned with the a.c. impedance of a temperature-dependent semiconductor specimen when a small a.c. voltage is applied superimposed on a d.c. bias which determines the operating condition of the specimen. The model employed assumes purely radial heat flow due to the passage of electrical current. The a.c. resistance is found to be in general different from the isothermal or the steady-state differential resistance. Under certain conditions, the a.c. resistance can become zero or even negative giving rise to thermal instability.
A systematic approach in designing a complex system with VHDL

As the size and complexity of digital systems increase continuously, hardware description language (HDL) based design methodology is quickly becoming the main stream in today's digital system design. Although many of the HDL-based design practices follow the bottom-up fashion, the real strength of HDL is that it facilitates the top-down design process where higher level design concepts can be described and verified without delving into implementation details. This paper describes a complex system design practice using VHDL where a multi-level top-down design approach was adopted. >
Impact of pharmacist-managed warfarin on patient outcomes in an academic medical center.

Table 1 Patient Demographics | Variable (mean) | Pharmacist-Managed (n=54) | Physician-Managed (n=108) | p value | |:---------------:| ------------------------- | ------------------------- | ------- | | Gender (M/F) | 35 / 19 | 62 / 46 | 0.37 | | Age
Ligand interactions with cholinergic receptor-enriched membranes from Torpedo: influence of agonist exposure on receptor properties.

Carbamylcholine and a nitrogen-substituted mononitroxide congener of decamethonium (I) show an inhibitory capacity toward the binding of cobra α-toxin to membranes enriched in cholinergic receptor that is dependent on the duration of exposure of the quaternary ligand prior to adding toxin. This behavior is characterized by (a) inhibition of the initial rate of toxin binding, which depends on the duration of ligand conditioning, (b) depression of the equilibrium binding of toxin, which at short exposure intervals cannot be accounted for by the decrease in association rate for toxin binding, and (c) a slow change in receptor state, in which the affinity for ligand is increased. The last can be demonstrated directly by electron spin resonance measurements of the free and bound resonance peaks of the spin-labeled bisquaternary ligand. The slow increase in affinity measured by ESR appears to be slightly smaller than the increased affinity calculated from conditioning effects of ligand exposure on the initial rate of toxin binding. The spin-labeled ligand is completely dissociated by excess toxin and binds to one site per toxin binding site. Conditioning effects of the ligands are lost upon solubilization of the receptor with Triton X-100. In contrast to the above ligands, the antagonist d -tubocurarine does not show time-dependent inhibition of toxin binding, and its interaction with the receptor-enriched membranes appears to be competitive with toxin binding.
Volcanic ash deposits in the Gulf of Alaska and problems of correlation of deep-sea ash deposits

Abstract The study of sediment cores from the Gulf of Alaska reveals the occurrence of three distinct ash layers or sediment intervals abundant in volcanic ash. The refractive index of the glass fragments of the upper layer is 1.485 ± 0.002. The ash is composed of 95% glass with an approximate silica content of 74%. The Katmai volcanic eruption of 1912 is considered to be the source of the ash which is more widespread than previously described. The middle ash is dark brown and of basaltic composition with a refractive index of 1.565. It occurs in some areas as a distinct layer and in others, mixed with non-volcanic sediment. The physical properties, stratigraphic relationships and composition suggest that the ash in this unit is derived from a common but unknown source. The lower layer of volcanic ash, approximately andesitic in composition, is recorded in two cores. The age of this layer, as determined by radiocarbon dating of carbonate sediments above and below the ash is inferred to be older than 25,000 years. The petrography of these deposits is discussed. Included in this study are brief discussions of deep-sea ash deposits in the north Atlantic Ocean, Mediterranean Sea, Gulf of Mexico and equatorial Pacific Ocean (Worzel ash). Some of the famous volcanic eruptions of historic record are briefly reviewed such as the Tambora in the East Indies, the Volcan Quizapu in Chile, the Hekla eruption of 1947 in Iceland, and the Glacier Peak eruption of 6,700 years ago in the northern Cascades, U.S.A. Some of the problems of correlation of deep-sea ash deposits are discussed. The possible world-wide occurrence of Worzel deep-sea ash ( Ewing et al., 1959) and the cometary origin of the ash is discounted.
Randomized, Controlled Trial Comparing Synchronized Intermittent Mandatory Ventilation and Synchronized Intermittent Mandatory Ventilation Plus Pressure Support in Preterm Infants

BACKGROUND. Prolonged mechanical ventilation is associated with lung injury in preterm infants. In these infants, weaning from synchronized intermittent mandatory ventilation may be delayed by their inability to cope with increased respiratory loads. The addition of pressure support to synchronized intermittent mandatory ventilation can offset these loads and may facilitate weaning. OBJECTIVE. The purpose of this work was to compare synchronized intermittent mandatory ventilation and synchronized intermittent mandatory ventilation plus pressure support in weaning from mechanical ventilation and the duration of supplemental oxygen dependency in preterm infants with respiratory failure. METHODS. Preterm infants weighing 500 to 1000 g at birth who required mechanical ventilation during the first postnatal week were randomly assigned to synchronized intermittent mandatory ventilation or synchronized intermittent mandatory ventilation plus pressure support. In both groups, weaning followed a set protocol during the first 28 days. Outcomes were assessed during the first 28 days and until discharge or death. RESULTS. There were 107 infants enrolled (53 synchronized intermittent mandatory ventilation plus pressure support and 54 synchronized intermittent mandatory ventilation). Demographic and perinatal data, mortality, and morbidity did not differ between groups. During the first 28 days, infants in the synchronized intermittent mandatory ventilation plus pressure support group reached minimal ventilator settings and were extubated earlier than infants in the synchronized intermittent mandatory ventilation group. Total duration of mechanical ventilation, duration of oxygen dependency, and oxygen need at 36 weeks9 postmenstrual age alone or combined with death did not differ between groups. However, infants in synchronized intermittent mandatory ventilation plus pressure support within the 700- to 1000-g birth weight strata had a shorter oxygen dependency. CONCLUSIONS. The results of this study suggest that the addition of pressure support as a supplement to synchronized intermittent mandatory ventilation during the first 28 days may play a role in reducing the duration of mechanical ventilation in extremely low birth-weight infants, and it may lead to a reduced oxygen dependency in the 700- to 1000-g birth weight strata.
Feedback Combustion Control Using Chemi-Ionization Probe in Supersonic Flow of Combustion Products

DOI: 10.2514/1.43809 The results of the present work demonstrate feasibility of feedback combustion control using a chemi-ionization current sensor placed in a supersonic flow of combustion products. Operated in the saturation regime, the ionization sensor (Thomson probe) removes nearly all electrons from the flow and therefore acts as a global chemi-ionization detector. The results show that a relation between the equivalence ratio in the combustor and the chemi-ionization current in the M 3 flow can be used to maintain the equivalence ratio at the desired value. The experiments have shown that using different target values of the chemi-ionization current in the feedback control program enforces transition from near-stoichiometric to fuel-lean and from fuel-lean to near-stoichiometric conditions in the combustor. The experiments have also demonstrated that the feedback control system can counter external perturbations, which either increase or decrease the equivalence ratio in the combustor and bring the fuel–oxidizer mixture composition back to the specified values. The combustion feedback control system based on a Thomson chemi-ionization probe is simple and straightforward and can be easily adapted for practical applications.
Thermodynamics of the hydrolysis reactions of adenosine 3′,5′-(cyclic)phosphate(aq) and phosphoenolpyruvate(aq); the standard molar formation properties of 3′,5′-(cyclic)phosphate(aq) and phosphoenolpyruvate(aq)

Abstract Molar calorimetric enthalpy changes ΔrHm(cal) have been measured for the biochemical reactions {cAMP(aq) + H2O(l)=AMP(aq)} and {PEP(aq) + H2O(l)=pyruvate(aq) + phosphate(aq)}. The reactions were catalyzed, respectively, by phosphodiesterase 3′,5′-cyclic nucleotide and by alkaline phosphatase. The results were analyzed by using a chemical equilibrium model to obtain values of standard molar enthalpies of reaction ΔrHm∘ for the respective reference reactions {cAMP−(aq) + H2O(l)=HAMP−(aq)} and {PEP3−(aq) + H2O(l)=pyruvate−(aq) + HPO2−4(aq)}. Literature values of the apparent equilibrium constants K′ for the reactions {ATP(aq)=cAMP(aq) + pyrophosphate(aq)}, {ATP(aq) + pyruvate(aq)=ADP(aq) + PEP(aq)}, and {ATP(aq) + pyruvate(aq) + phosphate(aq)=AMP(aq) + PEP(aq) + pyrophosphate(aq)} were also analyzed by using the chemical equilibrium model. These calculations yielded values of the equilibrium constants K and standard molar Gibbs free energy changes ΔrGm∘ for ionic reference reactions that correspond to the overall biochemical reactions. Combination of the standard molar reaction property values (K, ΔrHm∘, and ΔrGm∘) with the standard molar formation properties of the AMP, ADP, ATP, pyrophosphate, and pyruvate species led to values of the standard molar enthalpy ΔfHm∘ and Gibbs free energy of formation ΔfGm∘ and the standard partial molar entropy Sm∘ of the cAMP and PEP species. The thermochemical network appears to be reasonably well reinforced and thus lends some confidence to the accuracy of the calculated property values of the variety of species involved in the several reactions considered herein.
Efficient algorithms for optimistic crash recovery

Recovery from transient processor failures can be achieved by using optimistic message logging and checkpointing. The faulty processors roll back, and some/all of the non-faulty processors also may have to roll back. This paper formulates the rollback problem as a closure problem. A centralized closure algorithm is presented together with two efficient distributed implementations. Several related problems are also considered and distributed algorithms are presented for solving them.
Exploratory data analytic techniques to evaluate anticancer agents screened in a cell culture panel.

Information theory is used to provide a measure of selectivity, i.e., the degree to which a drug has preferential toxicity or growth inhibition for one or a few cell lines from a large panel. The selectivity measure is intended to complement a measure of differential growth inhibition in evaluating the drug development potential of a new compound. Also, a similarity measure obtained from information theory is used to classify drugs according to their pattern of responses on the panel. Some structure-activity relations emerge. This work is applied to 176 agents selected to be tested by the National Cancer Institute in about 50 cell lines.
Retention of Construction Teachers in Secondary Education

The purpose of this study was to investigate the reasons construction teachers left the teaching profession in their first 5 years of service, or if they stayed, the dominant factors that caused them to consider leaving the profession and the factors that were causing them to remain in the field. The researchers created a survey instrument and collected data from teachers remaining in the profession and those that left the profession. Data revealed a significant difference in the retention rate of 2-year alternatively certified teachers and 4-year teaching degreed teachers. The 4-year teaching degreed teacher had a higher retention rate. The data also revealed the only significant difference in why 2-year certified and four-year teaching degreed teachers had considered leaving the profession was the 2-year certified teachers were considering leaving because of poor opportunities for professional advancement. Considerations of stayer teachers to leave the profession included low salary, inadequate support ...
SAFETY WARNINGS IN TRACTOR OPERATION MANUALS, 1920-1980: MANUALS AND WARNINGS DON'T ALWAYS WORK

This article studies the history of one of the most critical, unresolved problems in mechanized agriculture: Tractor operators do not read the operation manuals, particularly the safety warnings. The result: sustained death and injury of these operators for well over a century. The article tracks the emergence of warnings in tractor operator manuals found in the archives of the University of Nebraska Tractor Test Museum (1919-2007), describes efforts of manufacturers during this time to alert operators to dangers associated with tractors, and concludes with a summary of current research on tractor safety and the problem that remains unresolved: how to change the culture of farmers who use these implements, critical to agriculture production, to encourage them to read and follow safety practices.
Synthesis of CdS and ZnS nanowires using single-source molecular precursors.

Single-source molecular precursors were used to synthesize II−VI compound semiconductor nanowires for the first time. Cadmium sulfide and zinc sulfide nanowires were prepared using cadmium diethyldithiocarbamate, Cd(S2CNEt2)2, and zinc diethyldithiocarbamate, Zn(S2CNEt2)2, respectively, as precursors in a gold nanocluster-catalyzed vapor−liquid−solid growth process. High-resolution transmission electron microscopy studies show that the CdS and ZnS nanowires are single-crystal wurtzite structures with stoichiometric compositions. In addition, photoluminescence measurements demonstrate that these nanowires exhibit high-quality optical properties. The applicability of our approach to the synthesis of other compound and alloy semiconductors nanowires as well as nanowire heterostructures of these materials is discussed.
Intragastric drug self-administration by rats exposed successively to morphine and ethanol

Abstract Male Sprague-Dawley rats were implanted with intragastric cannulas for self-administration of drug solutions by bar-pressing on a continuous reinforcement schedule in 10-hour daily sessions. Similar levels of responding were observed for doses per infusion of 3.0 mg/kg morphine sulfate and 25 mg/kg ethanol in separate groups of rats. When rats that showed self-administration of a morphine solution over a 5-day period were then given access instead to ethanol for 5 days, the number of infusions taken did not deviate significantly between the two periods. However, rats selected from a small minority that failed to take morphine under these conditions also failed to manifest ethanol self-administration behavior. The data can be seen to support a possible concurrence or similarity between innate factors determining acceptance or rejection of morphine and ethanol as objects of self-administration behavior.
Current and Future Practices in Hospital Foodservice

Abstract Objectives To identify current operational practices and expectations for future practices in hospital foodservice; establish the probability that current practices will change; and determine whether differences in practices exist on the basis of profit status and hospital size. Design A questionnaire, to determine current practices, probability of change, and expectations for future practices, was mailed to foodservice directors. Subjects A random sample of 500 foodservice directors in US hospitals with 200 or more beds. A total of 214 questionnaires were returned for a response rate of 43%. Statistical analysis Descriptive statistics were used to report current practices, probability of change, and expectations for future practices. The Kruskal-Wallis test was conducted to examine whether the probability of change ratings differed on the basis of hospital profit status and size. χ 2 Analysis was used to examine whether expectations for future practices differed based on hospital profit status and size. Results Currently 81% of hospital foodservice departments have fewer than 100 employees; 73% have revenue budgets of less than $2 million; 49% have expense budgets greater than $2 million; 55% use a selective menu, often (43%) 1-week in length; 74% use conventional food production technology; 81% have a centralized, hot tray line; 91% operate a cafeteria; 96% do on-site catering; 69% have differential pricing for employee meals; 58% have subsidized employee meals; and 19% have coffee kiosks. Changes in current practices are expected in several areas. Foodservice directors expect to serve meals to fewer inpatients (71%), employ less staff (73%), have smaller expense budgets (70%), and generate more revenue (61%). Kruskal-Wallis and χ2 analyses indicated few differences on the basis of hospital profit status and size. There was little consensus among directors on how to best respond to these environmental changes. Applications Hospital foodservice practices will change in the future. Foodservice directors are using a variety of strategies (eg, revenue-generating ventures, menu changes) to respond to current environmental changes. Increased emphasis will be placed on running a hospital foodservice department as a profit center rather than a cost center. J Am Diet Assoc. 2000; 100:76-80.
Apparent “negative cooperativity” kinetics in the absence of a nonlinear Scatchard plot of thyrotropin-receptor interaction in a human thyroid adenoma

Abstract A human thyroid adenoma (benign nodule) was identified which exhibited a linear Scatchard plot of 125I-TSH binding, characteristic of a single class of binding site with high affinity (Kd = 0.5±0.1 nM) and low binding capacity (0.8±0.2 pmol/mg protein). In contrast, Scatchard analysis of binding to adjacent normal thyroid was nonlinear, suggesting the presence of high and low-affinity binding sites with Kd's of 0.4±0.2 and of 27.9±11.0 nM and capacities of 0.7±0.3 and 1.8±1.0 pmol/mg protein, respectively. Dissociation of bound 125I-TSH from membranes of both adenoma and normal tissue revealed identical enhancement of dissociation in the presence of excess native hormone, thought to be evidence for the “negative cooperativity” model of hormone-receptor interaction. Furthermore, adenylate cyclase from both tissues was equally responsive to TSH. Thus, a thyroid adenoma which contains TSH-responsive adenylate cyclase still exhibited enhanced dissociation by native hormone, even though Scatchard analysis yielded a single, non-cooperative class of binding sites. This suggests that enhanced dissociation of bound hormone does not provide a demonstration of negatively-cooperative site-site interaction. Furthermore, nonlinear Scatchard plots, typical of TSH binding in normal thyroid, represent two classes of binding sites, of which the high affinity type is responsible for stimulation of adenylate cyclase.
Limiting in feedback control systems

Limiting effects exist in feedback control systems because of the restricted range of operation of components or because of purposeful limiting introduced for the protection of equipment. Such limiting effects increase the difficulties associated with the analysis and synthesis of systems because of the nonlinear mathematical relations which result. As such effects can markedly modify system performance, there is a practical need for a simplified method for taking them into account. The effect of limiting on system performance is studied here in terms of the frequency response of the system. It is found that limiting of the most elementary form ? simple limiting ? improves system stability, except in those systems which are conditionally stable or have a conditional degree of stability. In such instances, precautions are suggested to prevent the limiting action from adversely affecting system performance. It is found that the velocity limiting of a servomotor introduces the effect of phase lead and hence can be used to improve system stability. On the other hand, the limiting of servomotor acceleration directly or indirectly (as by means of current or pressure limiting) is found to introduce a phase-lag effect which can be detrimental to system performance. Electronic analogue computer techniques were employed to obtain much of the data presented here.
Clinical evaluation of quantitative differences in ultraviolet absorption of compounds containing the substituted benzoic acid nucleus.

The property of resonating compounds to absorb solar light has been investigated in the field of physics for at least fifty years. The relationship of the protection of skin surfaces from ultraviolet light rests upon the formula l - Eo = hV where the energy of the compound is initially Eo; energy in the excited state is Ei; and V is the frequency of light absorbed, h is Plank's constant. (Note: Frequency is inversely related to wavelength (A°).) Compounds which possess the physical property of absorbing energy in the range 2900A°-3170A° have previously been investigated for their advantages in preventing sunburn. They may also offer a prophylactic weapon in such diseases as lupus erythematosus and solar urticaria. Kesten and Slatkin have most recently offered a detailed classification and history of diseases related to sunlight and light sensitivity.
Salvinorin A: A novel and highly selective κ-opioid receptor agonist

Abstract κ-opioid receptors (KORs) represent the principal site of action of dynorphin and related neuropeptides. Recently, Salvinorin A—a naturally occurring neoclerodane diterpene hallucinogen was identified to be a highly selective KOR agonist. In this brief review we summarize the known chemistry, pharmacology and biology of salvinorin A. Because salvinorin A profoundly alters human consciousness and perception, a study of how salvinorin A exerts its actions on KORs may yield novel insights into the molecular and cellular basis of uniquely human higher cortical functions.
The Peace and Love Generation: Changing Attitudes toward Sex and Violence among College Youth

The period of the sixties marked the emergence of a distinctive generational ideology among a substantial segment of American youth. This "peace and love" ideology featured a high degree of age group consciousness and unique integration of life style and political concerns, the psychological foundation for which was laid by the increased differentiation of age roles and de-differentiation of sex roles associated with advanced industrial development. The expansion of higher education, emergence of the multibillion dollar youth market, and growth of the mass media provided the means by which many such youth were able to achieve consciousness of their common interests and join active generation units with distinctive styles of expression. The war in Indochina constituted the traumatic episode which differentiated the various age groups in America and galvanized the middle class, college segment of the youth cohort into action. Language: en
Family influence on disordered eating: The role of body image dissatisfaction

Research has linked an appearance-focused family culture (including parental commentary about weight/size) with increased disordered eating and body image dissatisfaction in daughters. Since body image dissatisfaction is also a risk factor for disordered eating, body image dissatisfaction may contribute to the link between family focus on appearance and disordered eating. This correlational study included a sample of 268 college women who completed the Family Influence Scale, Bulimia Test - Revised, Body Shape Questionnaire, and a series of items about their parents' comments about their weight/size. Both family appearance focus and daughters' body image dissatisfaction predicted increased disordered eating in daughters. Additionally, body image dissatisfaction partially mediated the influence of family appearance focus on daughters' disordered eating. No specific type of parental comments regarding weight/size emerged as a superior predictor of eating disturbance, but encouragement to control weight/size was a stronger predictor of body dissatisfaction than other types of parental comments.
Left aortic arch and right descending aorta

Abstract A case of left aortic arch and right descending aorta in a 17 year old boy is herein reported. To the best of our knowledge, this is only the sixth case of this anomaly to be reported. The anomaly was first discovered at a preoperative examination when the patient was 10 years old, and he has been observed since that time. Selective angiocardiography and arteriography confirmed the presence of the anomaly. They also revealed an anomalous origin of the right subclavian artery from the descending aorta, a right ligamentum arteriosum and a persistent left superior vena cava. There has been no significant encroachment on the mental or physical development or cardiovascular reserve.
Kinetic α-deuterium isotope effects for enzymatic and nonenzymatic hydrolysis of nicotinamide-β-riboside

Abstract The kinetic α-secondary deuterium isotope effect, k H k D , for the pH-independent hydrolysis of nicotinamide riboside, yielding nicotinamide and ribose, in water at 25 ° is 1.14, establishing that this reaction proceeds with unimolecular substrate decomposition to yield a carboxonium ion, or related species, in the rate-determining step. Surprisingly, the corresponding isotope effect for the base-catalyzed decomposition of the same substrate is 1.12, a value indicating considerable sp2 character at the Cl′ position in the transition state for this reaction. A similar result, k H k D = 1.15 , was obtained for base-catalyzed hydrolysis of NAD+. The kinetic alpha deuterium isotope effect for the pig brain NAD glycohydrolasecatalyzed hydrolysis of nicotinamide riboside is 1.08. This value suggests that CN bond cleavage to form an intermediate carboxonium ion, or structurally related species, is at least partially rate-determining. In contrast, the corresponding value for the hydrolysis of this substrate catalyzed by Escherichia coli nicotinamide ribonucleotide glycohydrolase is very near unity, a result consistent with several interpretations including a rate-determining enzyme isomerization reaction.
The influence of land use and potamodromous fish on ecosystem function in Lake Superior tributaries

Allochthonous nutrients and carbon are recognized as dominant controls on biogeochemistry of low-order streams. In some systems, potamodromous fish may provide a complementary source of material as they deliver lake-derived materials to spawning streams. This study examines nutrient and carbon inputs from terrestrial ecosystems and migratory fishes to streams in undeveloped watersheds in northern Michigan, USA. We compared watershed and riparian area, slope, and landcover to nutrient concentrations at 26 sites, as well as whole-stream metabolism at 5 sites. Despite low levels of agricultural land use (0–3%), agriculture had the largest influence on stream chemistry as indicated by higher dissolved organic carbon (DOC), ammonium, silica, and chloride concentrations at the watershed level, and increased DOC and chloride at the riparian level. Ecosystem respiration and net primary production increased with watershed and riparian area, and the proportion of managed forest. To quantify inputs from fish, we monitored the spawning migrations of white (Catostomus commersonii) and longnose (C. catostomus) suckers at one site, and measured nutrients and stream metabolism above and below an impassable dam. Nutrient concentrations were uniformly low and did not increase during the fish migration; however, temporal shifts in stream metabolism during sucker migration suggest that fish influenced respiration, presumably by providing high-quality carbon and bioavailable nutrients. We conclude that both watershed land use and fish migrations provide important sources of allochthonous material to these oligotrophic streams. Recognizing the bi-directional nature of allochthonous inputs is important for understanding controls on ecosystem functioning in low-order streams.
Norepinephrine depolarizes lateral horn cells of neonatal rat spinal cord in vitro.

Abstract Superfusion of norepinephrine (NE) (1–50 μM) onto lateral horn cells, including antidromically identified sympathetic preganglionic neurons (SPNs), situated in thin transverse neonatal rat thoracolumbar spinal cord slices caused a membrane depolarization and repetitive cell discharges. The NE depolarization was associated with an increase in membrane resistance, and the response became smaller upon conditioning hyperpolarization; a clear reversal of polarity, however, was not observed. Pretreating the slices with phentolamine and prazosin but not yohimbine or propranolol prevented the depolarizing effect of NE. This finding, in conjunction with the evidence of the presence of noradrenergic fibers in the spinal cord, suggests that NE may serve as an excitatory neurotransmitter to neurons of the lateral horn.
An in situ nanoindentation specimen holder for a high voltage transmission electron microscope

We describe in detail, the design, construction, and testing of a specimen holder that allows for the nanoindentation of surfaces while viewing in cross-section in a high voltage transmission electron microscope (TEM). This nanoindentation specimen holder, having three-axis position control of a diamond indenter in combination with micromachined specimens, allows for the first time the dynamic observation of subsurface microstructure evolution under an indenter tip. Additionally, the sample design techniques that have been developed for these procedures may eliminate the need for TEM specimen preparation for additional ex situ nanoindentation experiments. Initial experimental results from in situ indentation of Si samples in the high voltage electron microscope are reported here to demonstrate the capability of this new specimen holder.
Photocatalytic conversion of methane

Investigation of the direct conversion of methane to transportation fuels has been an ongoing effort at PETC for over 10 years. One of our current areas of research is the conversion of methane to methanol under mild conditions using light, water, and a semiconductor photocatalyst. The use of three relatively abundant and inexpensive reactants, light, water, and methane, to produce methanol is attractive. Research in our laboratory is directed toward applying techniques developed for the photochemical splitting of water to methane conversion. The reaction sequence of interest initially produces a hydroxyl radical with the aid of a doped tungsten oxide photocatalyst and an electron transfer molecule. Hydroxyl radical can then react with a methane molecule to produce a methyl radical. In the preferred reaction pathway, the methyl radical then reacts with an additional water molecule to produce methanol and hydrogen.
Real-time dual-mode standard/complex Fourier-domain OCT system using graphics processing unit accelerated 4D signal processing and visualization

We realized a real-time dual-mode standard/complex Fourier-domain optical coherence tomography (FD-OCT) system using graphics processing unit (GPU) accelerated 4D (3D+time) signal processing and visualization. For both standard and complex FD-OCT modes, the signal processing tasks were implemented on a dual-GPUs architecture that included λ-to-k spectral re-sampling, fast Fourier transform (FFT), modified Hilbert transform, logarithmic-scaling, and volume rendering. The maximum A-scan processing speeds achieved are >3,000,000 line/s for the standard 1024-pixel-FD-OCT, and >500,000 line/s for the complex 1024-pixel-FD-OCT. Multiple volumerendering of the same 3D data set were preformed and displayed with different view angles. The GPU-acceleration technique is highly cost-effective and can be easily integrated into most ultrahigh speed FD-OCT systems to overcome the 3D data processing and visualization bottlenecks.
Force Spectroscopy of the Iron Atom in Heme Proteins

Nuclear resonance vibrational spectroscopy (NRVS) selectively reveals the complete vibrational density of states (VDOS) of a Mossbauer probe nucleus within a protein. Frequency moments of the VDOS determine effective force constants for 57Fe at the active sites of cytochrome c (cyt c) and deoxymyoglobin (Mb). The stiffness measures the force needed to displace the Fe with the other atoms fixed, and probes the nearest neighbor interactions with the Fe. The stiffness of the low spin Fe environment in cyt c greatly exceeds that for the high spin Fe in Mb, reflecting the shorter Fe–N bonds to the heme. Moreover, a significant stiffness decrease upon oxidation of cyt c tracks the longer Fe–S bond to Met 80 in the oxidized protein. Quantitative comparison with 57Fe/54Fe frequency shifts suggests that Fe-L vibrations contribute to the Raman signal of cyt c recorded in resonance with the heme Soret band. The resilience measures the force needed to displace the Fe with the surrounding atoms free to respond, and determines the magnitude of the thermal fluctuations of the Fe on a time scale determined by the experimental energy resolution (ca. 4 ps for the results reported here). Quantitative agreement with the temperature-dependent mean squared displacement determined from independent Mossbauer measurements confirms longstanding assumptions that vibrational motion dominates thermal fluctuations of the heme Fe below the well-known dynamical transition at ca. 200 K and identifies THz frequencies below 100 cm−1 as the dominant contribution. The resilience increases significantly for cyt c with respect to Mb, which we attribute to the increased number of covalent links between heme and peptide in the former protein. Molecular dynamics simulations reproduce the increased resilience of cyt c, but find no significant change with oxidation state.
Reflection of Very Slow Electrons

A monoenergetic electron beam from an electrostatic analyzer has been used to measure reflection coefficients of polycrystalline platinum, single-crystal germanium, and single-crystal copper. The lower limit of primary energy is 0.2-0.3 ev. The contact potential difference between target and collector is measured and compensated by the Kelvin method. Targets are cleaned by heating and argon-ion bombardment. Polycrystalline platinum exhibits a maximum at 2.5 ev, and a rise near zero primary energy attributed to a patch effect. Germanium, after ion-bombardment cleaning, exhibits a low reflection coefficient which decreases to a value between 0.05 and 0.10 at the low-energy limit. Copper, after heating and also after ion-bombardment cleaning, shows a reflection coefficient with weak structure, decreasing nearly to zero at the limit of measurement. These results are in general agreement with the predictions of Herring and Nichols regarding the transparency of surface barriers. Observations have also been made on these targets following argon-ion bombardment and exposure to gases.
Authoritarianism in Black and White: Testing the Cross-Racial Validity of the Child Rearing Scale

Using a scale of child rearing preferences, scholars find that African Americans are far more authoritarian than Whites. We argue that this racial gap in authoritarianism is largely a measurement artifact. The child rearing scale now used to measure authoritarianism is cross-racially invalid because it draws heavily on a metaphor about hierarchy. Akin to someone who favors enforcing conformity in a child, the authoritarian is thought to be inclined toward enforcing conformity in social subordinates. In both cases, one’s perspective is drawn from a position of relative power. We believe this metaphor is effective among members of a majority racial group because individual dominance at home meshes with group dominance in society. For members of a racial minority, we believe this metaphor breaks down. Using multi-group confirmatory factor analysis, we establish that Blacks and Whites construe the child rearing items differently. Consequently, authoritarianism correlates highly with the things it should for Whites, but rarely so for Blacks. Using an illegal immigration experiment, we then show divergent patterns of intolerance based on the same child rearing scale. Our results highlight measurement’s role in producing large racial gaps in authoritarianism, while illuminating the racial boundaries of the child rearing scale.
Within word structure in the tip-of-the-tongue phenomenon.

Definitions of four rare words were read to 259 undergradua tes. Those subjects who were in the tip-of-the-tongue (TOT) state recorded all the letters they knew. The within-word structure of the resulting 101 partial recalls was indistinguishable from that of similar sounding words from earlier studies. In both sets of data, morpheme-like clusters of letters were evident. The recall of high frequency clusters at the end of words could not be explained in terms of sophisticated guessing. The results support a distinct memory system for word names which is organized for use in the production and perception of speech and writing.
Radio flares from AE Aquarii: a low-power analog to Cygnus X-3?

The magnetic cataclysmic variable AE Aquarii has been observed at 1.5, 4.9, 15, and 22.5 GHz. The source shows temporal variations in the flux density, often with a flarelike morphology. The flux variations are at times extreme, with values ranging from 1-12 mJy at 15 GHz; the degree of variability increases with frequency. The spectrum shows a variety of short-term behavior, at times increasing as nu, at other times decreasing with nu, and at still others flat. The long-term average of the spectrum increases as nu exp 0.3-0.4. No significant degree of circular polarization was observed. The source properties can be explained as a superposition of flare events in which electrons are accelerated to relativistic energies which then emit synchrotron radiation in discrete, expanding sources. The origin of the flare events may be connected to the disruption of the accretion disk some ditance from the white dwarf primary. The radio emission of AE Aqr shows similarities to the low-level flares from Cygnus X-3.
Feeding china: a confident view

Abstract Lester R. Brown's recent argument, that large Chinese grain imports could drive world prices to dangerously high levels by the year 2030, is mistaken on three counts. First, Brown is badly mistaken to argue that China's own grain production will decline by 20% in the next three decades; the consensus among more careful analysts is that Chinese grain production will continue to increase. Second, Brown is wrong to characterize Chinese grain imports, when they do occur, as something to worry about; increased reliance on imports is going to be the best way for China to protect its rural environment and ensure continued income growth and improved nutrition for its population in the years ahead. Third, Brown is wrong to characterize international grain markets as incapable of servicing China's larger import needs; even if those needs should grow very large, real prices in international grain markets are likely to continue their long term trend of decline.
Recombinant Sindbis/Venezuelan Equine Encephalitis Virus Is Highly Attenuated and Immunogenic

Venezuelan equine encephalitis virus (VEEV) is an important, naturally emerging zoonotic virus. VEEV was a significant human and equine pathogen for much of the past century, and recent outbreaks in Venezuela and Colombia (1995), with about 100,000 human cases, indicate that this virus still poses a serious public health threat. The live attenuated TC-83 vaccine strain of VEEV was developed in the 1960s using a traditional approach of serial passaging in tissue culture of the virulent Trinidad donkey (TrD) strain. This vaccine presents several problems, including adverse, sometimes severe reactions in many human vaccinees. The TC-83 strain also retains residual murine virulence and is lethal for suckling mice after intracerebral (i.c.) or subcutaneous (s.c.) inoculation. To overcome these negative effects, we developed a recombinant, chimeric Sindbis/VEE virus (SIN-83) that is more highly attenuated. The genome of this virus encoded the replicative enzymes and the cis-acting RNA elements derived from Sindbis virus (SINV), one of the least human-pathogenic alphaviruses. The structural proteins were derived from VEEV TC-83. The SIN-83 virus, which contained an additional adaptive mutation in the nsP2 gene, replicated efficiently in common cell lines and did not cause detectable disease in adult or suckling mice after either i.c. or s.c. inoculation. However, SIN-83-vaccinated mice were efficiently protected against challenge with pathogenic strains of VEEV. Our findings suggest that the use of the SINV genome as a vector for expression of structural proteins derived from more pathogenic, encephalitic alphaviruses is a promising strategy for alphavirus vaccine development.