cssi/SciSciGPT-SciSciNet huggingface dataset:
Toward an organ based dose prescription method for the improved accuracy of murine dose in orthovoltage x-ray irradiators

Purpose: Accurate dosimetry is essential when irradiating mice to ensure that functional and molecular endpoints are well understood for the radiation dose delivered. Conventional methods of prescribing dose in mice involve the use of a single dose rate measurement and assume a uniform average dose throughout all organs of the entire mouse. Here, the authors report the individual average organ dose values for the irradiation of a 12, 23, and 33 g mouse on a 320 kVp x-ray irradiator and calculate the resulting error from using conventional dose prescription methods. Methods: Organ doses were simulated in the Geant4 application for tomographic emission toolkit using the MOBY mouse whole-body phantom. Dosimetry was performed for three beams utilizing filters A (1.65 mm Al), B (2.0 mm Al), and C (0.1 mm Cu + 2.5 mm Al), respectively. In addition, simulated x-ray spectra were validated with physical half-value layer measurements. Results: Average doses in soft-tissue organs were found to vary by as much as 23%–32% depending on the filter. Compared to filters A and B, filter C provided the hardest beam and had the lowest variation in soft-tissue average organ doses across all mouse sizes, with a difference of 23% for the median mouse size of 23 g. Conclusions: This work suggests a new dose prescription method in small animal dosimetry: it presents a departure from the conventional approach of assigning a single dose value for irradiation of mice to a more comprehensive approach of characterizing individual organ doses to minimize the error and uncertainty. In human radiation therapy, clinical treatment planning establishes the target dose as well as the dose distribution, however, this has generally not been done in small animal research. These results suggest that organ dose errors will be minimized by calibrating the dose rates for all filters, and using different dose rates for different organs.
Epizootiology of bluetongue virus: Transmission cycle, vectors, and serotypic distribution in the Americas

Abstract Bluetongue is an infectious, insect-transmitted viral disease of domestic and wild ruminants which was first described by Spreull in South Africa in 1905. The virus was first isolated and identified in the USA from sheep in California in 1952, and from cattle in Oregon in 1959, although “mycotic stomatitis” a clinical syndrome identical to bluetongue had been described as early as 1904. Since then bluetongue virus activity has been confirmed serologically or virologically in almost every part of the USA. Bluetongue virus appears to be enzootic in ruminants in the Western USA and in Florida, with occasional epizootic incursions into the northwestern, north central, and eastern states. The northeastern USA and Canada generally appear to be bluetongue free. Serologic or virologic documentation of bluetongue activity in ruminants is available from some of the Caribbean islands, Brazil, Colombia, Costa Rica and Mexico. The primary transmission cycle in the USA involves the biting gnat, Culicoides variipennis . Experimentally, the virus has been isolated from the semen of rams and bulls, and a transplacental transmission cycle has been demonstrated from infected pregnant cows to the fetus. Calves which are infected in utero may become persistently or latently infected carriers and viremia may be activated by the feeding of noninfected C. variipennis . Field evidence documenting the natural occurrence of these phenomena are available. The major proven biologic vector of BTV in the USA, C. variipennis , is found throughout the USA except for southern Florida, and occurs north into Canada and south into Mexico. This species is not found in the Caribbean islands, or in Central or South America. The vectors outside of the USA in the western hemisphere are not known. Experimentally, the oral susceptibility of C. variipennis females to infection with bluetongue virus has been shown to be genetically and environmentally influenced. Naturally occurring populations have been shown to vary in their oral susceptibility to BTV according to their geographic distribution. In the Western states where BTV is enzootic, the indigenous populations of C. variipennis are moderately to highly susceptible to oral infection with BTV. In the northeastern USA where BTV is not active, the natural C. variipennis populations are resistant to oral infection with BTV. Laboratory studies suggest that environmental conditions influence this resistance. Currently in the USA, four BTV serotypes, 10, 11, 13, and 17, are known to exist. All four serotypes have been isolated from ruminants or insects in California, Colorado, Montana and Nevada. Serotype 4 has been isolated from cattle which were being imported to the USA from Brazil. Viral isolates have not been reported from animals elsewhere in the Western hemisphere. Multiple serotypes have been shown to occur in the same ruminant at the same time.
How Interventions Might Improve Cognition in Healthy Older Adults

Many of the cognitive declines in healthy aging are moderated by experience, suggesting that interventions may be beneficial. Goals for aging outcomes include improving performance on untrained tasks, remediating observed cognitive declines, and ensuring preservation of functional ability. This selective review evaluates current progress towards these goals. Most research focuses on untrained tasks. Interventions associated with this outcome include games and exercises practicing specific cognitive skills, as well as aerobic exercise, and modestly benefit a relatively narrow range of cognitive tasks. Few studies have directly tested improvements in tasks on which individuals have been shown to experience longitudinal decline, so this goal has not been realized, though remediation can be examined rather easily. Little work has been done to develop psychometrically strong functional outcomes that could be used to test preservation of independence in everyday activities. Virtual reality approaches to functional assessment show promise for achieving the third goal.
Pacemaker for tracheal ventilation in the cockroach, Periplaneta americana (L.).

Abstract Previous attempts to identify respiratory pacemakers in insects have relied primarily upon cord-sectioning experiments. In this investigation electrophysiological techniques were used to locate the pacemaker in isolated and semi-isolated entire cords. The metathoracic ganglion was found to be the primary pacemaker, but shifting and multiple pacemakers occurred in some instances. Bursts of spikes initiated rhythmically (60–180/min) are propagated from the metathoracic to the terminal ganglion along internunciary fibres with a conduction velocity of approximately 3 m/sec, producing synchronous contraction of the abdominal expiratory musculature.
[The influence of strain, sex and age of mice on infection with Plasmodium berghei].

While studying the effect of a Plasmodium berghei infection on the course of leukemia1 in mice it was noted that DBA mice and Fi hybrid mice (C57 Black 9 XDBA d") differed in their resistance to malaria. Of the many investigators who have studied P. berghei in mice, none of whom we are aware has used inbred strains. By the use of such homogeneous strains of mice, differences in the reaction to the infection might become apparent and might lead to profitable investigations concerning genetic and nongenetic influences in infection. The present report deals with the course of P. berghei infections in inbred DBA/2 and C57 Black mice and their Fi hybrids, BD Fi mice.
Computations of fatigue crack growth with strain gradient plasticity and an irreversible cohesive zone model

Computations of fatigue crack growth with a first-order strain gradient plasticity (SGP) model and an irreversible cohesive zone model are reported. SGP plays a significant role in the model predictions and leads to increased fatigue crack growth rates relative to predictions with classical plasticity. Increased magnitudes of tractions and material separation at the crack tip together with reduced crack closure appear as the cause for accelerated crack growth in SGP. Under plane strain conditions SGP appears as an essential feature of the development of the crack closure zone. Size effects are explored relative to changes in internal material length scale as well as to structural length scales.
Factors associated with successful vocational rehabilitation in persons with arthritis.

OBJECTIVE The objective of this study was to analyze factors associated with successful vocational rehabilitation (return to work) among persons receiving state-federal vocational rehabilitation services because of work disability from arthritis. METHODS Multivariate analyses were used to determine the association of sociodemographic, disease-related, and agency factors with work outcome among a group of 456 persons with arthritis receiving state-federal vocational rehabilitation services during 1985-1988. RESULTS Agency-sponsored physical restoration services (P less than 0.0001) and retraining (P less than 0.0001) were the variables most strongly correlated with return to work. Age, sex, race, disease severity, financial status, and educational level assessed at intake were not significantly associated with work rehabilitation outcome. CONCLUSION Factors potentially amenable to agency intervention were more strongly associated with work rehabilitation outcome than were sociodemographic or disease-related variables.
Pathology of Common Murres and Cassin's Auklets Exposed to Oil

The histopathology of diving seabirds exposed to oil is described. Cassins Auklets (Ptychoramphus aleuticus) were experimentally exposed to weathered Santa Barbara Channel (CA) crude oil by external application to the breast plumage or wings. Beached Common Murres (Uria aalge) were recovered from an accidental oil spill of bunker C fuel oil. Exposed birds exhibited hepatocellular dissociation and hemosiderosis, renal tubular necrosis, and hemolytic anemia. Both unexposed and exposed birds exhibited numerous gastrointestinal lesions and parasites making interpretation of oil damage effects to the gastrointestinal system difficult. Burrow nesting auklets had a high incidence of pneumoconiosis while cliff nesting murres had no particulate inclusions on lungs. The results describe the extent of pathology to be expected in wild, free living seabirds.
Closure to ‘‘Analytical Determination of Distribution Uniformity for Microirrigation Tapered Laterals Laid on Uphill and Horizontal Slopes’’ by Sayed Hossein Sadeghi and Troy Peters

Based on the mathematical procedure presented in the discussion, the discusser concludes that Eq. (13) [Eq. (7)] is only valid under a limited design case where y 1⁄4 1. He justifies this statement by denoting that it is only under this circumstance that Eq. (12) reduces to (13). In the following, we show that this conclusion is incorrect: 1. Basically our reference equation for evaluating Hav is Eq. (13) and not Eq. (12). Eq. (12) cannot be considered as an exact solution of Hav because it is derived by substituting the following approximation equation:
A Herschel–Bulkley model for mud flow down a slope

The spreading and sediment deposit of a two-dimensional, unsteady, laminar mud flow from a constant-volume source on a relatively steep slope is studied theoretically and experimentally. The mud under consideration has the rheological properties of a Herschel–Bulkley fluid. The flow is of low-Reynolds-number type and has a well-formed wave front moving a substantial distance downslope. Due to the nonlinear rheological characteristics, a set of nonlinear partial differential equations is needed for this transient problem. Depth-integrated continuity and momentum equations are derived by applying von Karman's momentum integral method. A matched-asymptotic perturbation method is implemented analytically to get asymptotic solutions for both the outer region away from, and the inner region near, the wave front. The outer solution gives accurate results for spreading characteristics, while the inner solution, which is shown to agree well with experimental results of Liu & Mei (1989) for a Bingham fluid, predicts fairly well the free-surface profile near the wave front. A composite solution uniformly valid over the whole spreading length is then achieved through a matching of the inner and outer solutions in an overlapping region. The range of accuracy of the solution and the size of the inner and overlapping regions are quantified by physical scaling analyses. Rheological and dynamic measurements are obtained through laboratory experiments. Theoretical predictions are compared with experimental results, showing reasonable agreement. The impact of shear thinning on the runout characteristics, free-surface profiles and final deposit of the mud flow is examined. A mud flow with shear thinning spreads beyond the runout distance estimated by a Bingham model, and has a long and thin deposit.
Induction of oviposition in cycling Anolis carolinensis requires a β-adrenoreceptor blocker and a high dosage of arginine vasotocin

Abstract In a previous study, a high dosage (2.0 μg) of arginine vasotocin (AVT), following 10 μg of dichloroisoproterenol, induced oviposition in Anolis carolinensis at the end of the breeding season. The present study determined if a lower dosage of AVT (0.25 μg), comparable to that effective in other lizard species, would induce oviposition in cycling A. carolinensis . Only a high dosage of AVT (2.0 μg), following 10 μg of dichloroisoproterenol 15 min beforehand, induced oviposition. These results suggest that uterine smooth muscle of A. carolinensis is relatively insensitive to AVT.
Studies on the Site of Sex Pheromone Production in Dendroctonus pseudotsugae (Coleoptera: Scolytidae)

The digestive tract, malpighian tubes, and reproductive system of the female Douglas-fir beetle, Dendroctonus pseudotsugae Hopkins, are described. The accessory glands of the female reproductive system nearly doubled their length and width after the insects mated. Females producing the sex pheromone, i.e., unmated and feeding (newly emerged as well as re-emerged), possessed longer malpighian tubes than those not producing the pheromone, i.e., unmated and not feeding or mated and feeding. No such differences were found in the similar stages of the males. In arrestment tests to different organs of feeding, unmated females (foregut, midgut, malpighian tubes, and reproductive system), the male test beetles were arrested by the posterior part of the hindgut (rectum) only. When 2 drops of artificial borings from fresh Douglas-fir phloem were added to the organs tested, males were arrested also by the anterior part of the hindgut (small intestine) and by the malpighian tubes. The malpighian tubes of the unmated, feeding females, apparently are associated with the production of the sex pheromone.
Algorithm 937: MINRES-QLP for symmetric and Hermitian linear equations and least-squares problems

We describe algorithm MINRES-QLP and its FORTRAN 90 implementation for solving symmetric or Hermitian linear systems or least-squares problems. If the system is singular, MINRES-QLP computes the unique minimum-length solution (also known as the pseudoinverse solution), which generally eludes MINRES. In all cases, it overcomes a potential instability in the original MINRES algorithm. A positive-definite preconditioner may be supplied. Our FORTRAN 90 implementation illustrates a design pattern that allows users to make problem data known to the solver but hidden and secure from other program units. In particular, we circumvent the need for reverse communication. Example test programs input and solve real or complex problems specified in Matrix Market format. While we focus here on a FORTRAN 90 implementation, we also provide and maintain MATLAB versions of MINRES and MINRES-QLP.
A re-examination of body image distortion: evidence against a sensory explanation.

Objective This study was designed to assess female bulimic and control subjects' sensitivity to changes in their own and a model's body. Method: A video distortion camera was employed. Each subject (20 bulimics, 20 controls) compared a constant image of her undistorted body with 180 separate images of her body at various distortion levels (-16%, -12%, -8%, -4%, 0%, 4%, 8%, 12%, 16%) using the method of constant stimuli. The procedure was repeated using prerecorded images of a model. Results: Bulimics and controls were equally adept at detecting increases and decreases in the model's body and at detecting decreases in their own bodies. Bulimics, however, detected increases in their own bodies less well than controls. Discussion: The data provide evidence against a purely sensory/perceptual explanation of body image distortion. © 1997 by John Wiley & Sons, Inc. Int J Eat Disord 21: 175–180, 1997.
Journey to transcendence: Dostoevsky’s theological polyphony in Barth’s understanding of the Pauline KRISIS

Anticipating Mikhail Bakhtin’s appreciation for the unfinalizability of Fedor Dostoevskij’s universe, prominent Protestant theologian Karl Barth celebrates the Russian novelist’s presentation of “the impenetrable ambiguity of human life” characteristic of both the ending of Dostoevsky’s novels and Paul’s Epistle to the Romans. Barth’s unique reading of The Brothers Karamazov not only demonstrates the barrenness of the “theocratic dream” but also complements Bakhtin’s discussion of polyphony with an explicitly theological dimension by focusing on the dialogue between Creator and the created. Dostoevsky’s prophetic voice provides Barth with a poetic expression of the divine command that highlights the ethical dimension inherent in every theological choice.
Inhomogeneous broadening of the metal-nitrogen line in the surface enhanced Raman spectrum

Abstract The surface enhanced Raman line near 220 cm -1 in isoquinoline on silver is examined. It is shown to be inhomogeneously broadened and slightly asymmetric in shape. This is interpreted as reflecting a distribution surface molecule interactions.
Internal mobility of ferrocytochrome c

In the refinement of the X-ray diffraction structures of molecules, it is conventional to introduce atomic ‘temperature factors’ of the Debye–Waller form to characterize the widths of the electron density peaks corresponding to the atoms1. Although these factors are known to include a variety of contributions other than thermal fluctuations of the atomic positions2, recent progress in the refinement of protein structures has led to inferences concerning atomic mobilities from the temperature factor data for several proteins3–10. Atomic position fluctuations can be calculated independently by the molecular dynamics method, in which the classical equations of motion for the atoms of an equilibrated protein are solved on a computer11–16. We now show that the X-ray diffraction and dynamical simulation methods yield similar pictures of the atomic mobility in tuna ferrocytochrome c.
Noise level measurements in four Phoenix emergency departments.

Abstract Objective: Our objective was to compare the noise levels in 4 Phoenix-area emergency departments with published safety and comfort standards for noise levels. Methods: A device used to record sound levels was placed in the nurses' station of 4 Phoenix-area emergency departments for brief periods. Readings were compared with published safety and comfort standards. Results: Noise levels measured in the 4 emergency departments were higher than levels at which one can work comfortably. All the noise levels measured approached or exceeded levels that can cause feelings of anoyance ad other negative effects in individuals. Discussion: A comparison of actual noise levels in 4 local emergency departments with published safety and comfort standards found that 100% of the tested departments were too noisy. Anyone who spends any time exposed to this level of noise is subject to deleterious physical and psychological effects.
Stability and Asymptotic Behavior of Systems with Multi-time

Stability and asymptotic behavior of linear multi-time systems $\frac {\partial }{\partial t_{i}} u(\textbf {t})= A_{i} u (\textbf {t})$ +f i (t) is considered, where A i are generators of commuting C 0-semigroups on a Banach space. We formulate and prove versions of the results on exponential stability to homogeneous linear systems with multi-time. For non-homogeneous systems, we introduce the compatibility condition and obtain the variation-of-constants formula. Using simulta neous solutions of Sylvester equations, we obtain results on asymptotic almost periodicity of solutions.
Unforeseen Consequences of Excluding Missing Data from Next-Generation Sequences: Simulation Study of RAD Sequences

There is a lack of consensus on how next-generation sequence (NGS) data should be considered for phylogenetic and phylogeographic estimates, with some studies excluding loci with missing data, whereas others include them, even when sequences are missing from a large number of individuals. Here, we use simulations, focusing specifically on RAD (Restriction site Associated DNA) sequences, to highlight some of the unforeseen consequence of excluding missing data from next-generation sequencing. Specifically, we show that in addition to the obvious effects associated with reducing the amount of data used to make historical inferences, the decisions we make about missing data (such as the minimum number of individuals with a sequence for a locus to be included in the study) also impact the types of loci sampled for a study. In particular, as the tolerance for missing data becomes more stringent, the mutational spectrum represented in the sampled loci becomes truncated such that loci with the highest mutation rates are disproportionately excluded. This effect is exacerbated further by factors involved in the preparation of the genomic library (i.e., the use of reduced representation libraries, as well as the coverage) and the taxonomic diversity represented in the library (i.e., the level of divergence among the individuals). We demonstrate that the intuitive appeals about being conservative by removing loci may be misguided. (Next-generation sequencing; phylogenetic; phylogeography; RADseq; RADtags; species delimitation.)
Risk factors for intermediate-term survival after coronary artery bypass grafting

Abstract Background . Risk factors for short-term mortality after coronary artery bypass grafting are well established, but little is known about risk factors for intermediate-term mortality. Methods . We analyzed the outcomes of 11,815 patients undergoing coronary artery bypass grafting in one of the 43 cardiac surgery programs of the Department of Veteran Affairs. Risk factors for intermediate- and short-term mortality were determined using Cox proportional hazards regression models. Effects of risk factors during these two periods were explicitly compared. Results . We found important differences in mortality risk-factor sets between the intermediate- and short-term periods after coronary artery bypass grafting. The majority of predictors of intermediate-term mortality were noncardiac-related variables, whereas the majority of predictors of short-term mortality were cardiac-related variables. Impaired functional status, chronic obstructive pulmonary disease, and renal dysfunction had greater effects in the intermediate-term period. Previous heart operation, angina class III or IV, previous myocardial infarction, and preoperative use of an intraaortic balloon pump had greater effects in the short-term period. Conclusions . The risk factors for intermediate-term mortality identified in this study can augment preoperative risk assessment and counseling of patients. Clinicians should be aware of the importance of noncardiac-related variables as predictors of mortality in the intermediate-term period after coronary artery bypass grafting.
Nanoscale patterning of kinesin motor proteins and its role in guiding microtubule motility.

Biomolecular motor proteins have the potential to be used as ‘nano-engines’ for controlled bioseparations and powering nano- and microelectromechanical systems. In order to engineer such systems, biocompatible nanofabrication processes are needed. In this work, we demonstrate an electron beam nanolithography process for patterning kinesin motor proteins. This process was then used to fabricate discontinuous kinesin tracks to study the directionality of microtubule movement under the exclusive influence of surface bound patterned kinesin. Microtubules moved much farther than predicted from a model assuming infinite microtubule stiffness on tracks with discontinuities of 3 μm or less, consistent with a free-end searching mechanism. As the track discontinuities exceeded 3 μm, the measured and predicted propagation distances converged. Observations of partially fixed microtubules suggest that this behavior results from the interaction of the microtubules with the surface and is not governed predominately by the microtubule flexural rigidity.
THE USE OF RECEPTOR MODE TRAJECTORY ANALYSIS TECHNIQUES FOR CONTINGENCY PLANNING

ABSTRACT Spill trajectory models and computer analysis techniques have been used effectively in spill response programs. In addition to providing movement and spreading forecasts, these models also can be used to explore alternative operational scenarios. In many cases these same, basically deterministic, model formulations have been used to study hypothetical spills in a region where development is proposed, and the results used in contingency planning activities. When deterministic trajectory forecast models are used in this manner, a number of assumptions are necessary about the statistical nature of the dominant physical transport processes and the location of potential spill sites. This paper describes a new modeling procedure in which high-value target, or receptor, areas first are determined. These areas may be defined by using various environmental sensitivity mapping schemes. With this information, the model performs an inverse set of trajectory calculations and presents the output as two maps. T...
The Ethics Writings of Roger A. Brumback, MD

Roger A. Brumback, MD (1953-2013), a renaissance man, shared with the world his knowledge and opinions on many subjects. Thus, it should come as no surprise that ethics did not escape Dr Brumback's consideration. Reading Dr Brumback's vitae, I came across several publications that afford insights into topics that tugged at his moral fabric. Dr Brumback was a steadfast defender of the scientific method. Reading his commentaries, one gets the sense that Dr Brumback felt personally attacked when quackery challenged science. In addition, and as long-time Editor-in-Chief of the Journal of Child Neurology, Dr Brumback considered it a personal affront every time a paper he published, or for that matter published by any scientific journal, had to be retracted or corrected. In the following paragraphs, I review a selection of Dr Brumback's ethics writings.
Nucleophilic substitution of 1,2,4-triazines†

The reaction of 3-(methylthio)-5-carbethoxy-1,2,4-triazine (5) with ammonia was found to yield products from not only ammonia but also methanethiolate displacements. An account of the transformations and the products observed is given. The 3-position of 3,6-bis(methylthio)-5-carbamoyl-1,2,4-triazine (7) was shown to be more reactive than the 6-position toward nucleophilic substitution. Reduction at the 4,5 positions of triazine 5 occurred upon treatment with methanethiol under basic and neutral conditions.
The catalytic halides—XIII the interaction of gallium trichloride with ethyl, isopropyl, n-propyl, and t-butyl chlorides

Abstract The phase diagrams for the ethyl chloride—gallium chloride system were determined at four temperatures, −78.5, −64, −50, and −36°. A 1 : 1 addition compound exists in the solution phase as shown by molecular weight determinations. A solid phase corresponding to the 1 : 2 compound, C2H5Cl : Ga2Cl6, was identified, and the heat of dissociation, C2H5Cl : Ga2Cl6(s) ⇄ C2H5Cl(g) + Ga2Cl6(s) is 9.74 kcal/mole. The heat of solution of the 1 : 2 compound in ethyl chloride is 5.0 kcal/mole and the calculated m.p. is −29°. The phase diagram for the isopropyl chloride—gallium chloride system was determined at −64°. Solid phases corresponding to both the 1 : 2 and 1 : 1 compounds, (CH3)2CHCl : Ga2Cl6 and (CH3)2CHCl : GaCl3, were identified. At higher temperatures, solutions of gallium chloride in isopropyl chloride evolved hydrogen chloride at an appreciable rate. Similar observations were obtained for solutions of gallium chloride in n-propyl and t-butyl chloride. Isomerization of n-propyl to isopropyl chloride was also observed. Under the same conditions the rate of hydrogen chloride evolution is t-butyl > isopropyl > n-propyl > ethyl chloride, which is also the order of stability of the carbonium ions of the respective alkyl groups.
The State of Nonprofit and Philanthropic Studies Doctoral Education

This article examines the state of nonprofit and philanthropic studies doctoral education using several data sources: PhD student surveys, faculty surveys, the number of nonprofit articles published in academic journals, and completed dissertations in nonprofit and philanthropic studies. This article contributes to the nonprofit literature by capturing overall trends in nonprofit and philanthropic studies doctoral education, while asking fundamental questions about doctoral education—particularly about coherence and knowledge production. It presents several implications for both our understanding of the current state of nonprofit doctoral education—where we are—and where the field may be headed.
LAKE-RIVER INTERACTIONS: IMPLICATIONS FOR NUTRIENT DYNAMICS IN RESERVOIRS

ABSRACT Unlike small drainage lakes which receive nutrient inputs from relatively diffuse sources, reservoirs and other river-fed lakes receive a majority of their nutrient income from a single large source located distant from the lake's outlet. Interactions between lake and river, which are governed by hydrology, the thermal structure of the lake, and lake morphology, will, therefore, play an important role in determining the impact and ultimate fate of influent nutrients. These interactions may also affect the manner in which nutrients are recycled and/or distributed within the reservoir or river-fed lake and lead to the establishment of longitudinal gradients in concentration. Studies conducted at DeGray Lake, Ark., and West Point Lake, Ga., both large Corps of Engineers hydropower reservoirs, provide instructive examples of some of the effects of these interactions. Both lakes exhibit longitudinal gradients in nutrient and chlorophyll concentrations which are influenced by the hydrologic characterist...
Neuroapoptosis in the infant mouse brain triggered by a transient small increase in blood alcohol concentration

Exposure of infant rats or mice to ethanol on a single occasion during the period of rapid synaptogenesis can cause extensive apoptotic neurodegeneration throughout the developing CNS. Prior studies were designed to assess the effects of large doses of ethanol (comparable to heavy binge drinking), whereas in the present study, we sought to determine what magnitude and duration of blood ethanol elevation are required to trigger a minimal neuroapoptotic response. We found that a rise in blood ethanol to a level in the range of 50 mg/dl for a duration of 30 to 45 min was sufficient to trigger a significant neuroapoptosis response deleting approximately 20,000 neurons per infant mouse brain. Since blood ethanol elevations in this range are commonly achieved by humans in a social drinking context, a mother with only a moderate drinking habit might expose her fetus to such elevations on multiple occasions during pregnancy.
Examining a Large Keystroke Biometrics Dataset for Statistical-Attack Openings

Research on keystroke-based authentication has traditionally assumed human impostors who generate forgeries by physically typing on the keyboard. With bots now well understood to have the capacity to originate precisely timed keystroke sequences, this model of attack is likely to underestimate the threat facing a keystroke-based system in practice. In this work, we investigate how a keystroke-based authentication system would perform if it were subjected to synthetic attacks designed to mimic the typical user. To implement the attacks, we perform a rigorous statistical analysis on keystroke biometrics data collected over a 2-year period from more than 3000 users, and then use the observed statistical traits to design and launch algorithmic attacks against three state-of-the-art password-based keystroke verification systems.Relative to the zero-effort attacks typically used to test the performance of keystroke biometric systems, we show that our algorithmic attack increases the mean Equal Error Rates (EERs) of three high performance keystroke verifiers by between 28.6p and 84.4p. We also find that the impact of the attack is more pronounced when the keystroke profiles subjected to the attack are based on shorter strings, and that some users see considerably greater performance degradation under the attack than others. This article calls for a shift from the traditional zero-effort approach of testing the performance of password-based keystroke verifiers, to a more rigorous algorithmic approach that captures the threat posed by today’s bots.
Air pollution retention within a complex of urban street canyons: A two-city comparison

Abstract Uncharacterized microscale spatial and temporal variability in urban air pollutant concentration dynamics may contribute uncertainty or bias to epidemiological model results. In this study, a method for quantifying this variability is presented. Urban buildings were treated as a matrix of bluff bodies to estimate the retention of air pollution in the street canyons downstream of the buildings. This method was based primarily on bluff body theoretical work that derived functional relationships between nondimensional contaminant residence time ( H ) within a wake and the following fluid properties of the air: 1) Reynolds Number (Re), 2) street canyon height ( D ) to width ( W ) aspect ratio ( D / W ), and 3) turbulence intensity, defined as the square root of turbulence kinetic energy ( k ) divided by the freestream wind speed ( U ). Empirical relationships between these variables were built from sulfur hexafluoride (SF 6 ) concentration and meteorological data collected during the Midtown Manhattan 2005 (MID05) Study held in August, 2005 in Manhattan, NY, along with geographical information system (GIS) data describing the building topography. Results were then compared with results from a similar previous analysis using data collected during the Joint Urban 2003 (JU2003) study in Oklahoma City, OK. For the MID05 data, Re ranged from 1.65 × 10 6 to 7.74 × 10 7 , with a median of 1.13 × 10 7 . The range of Re was consistent with earlier observations from the JU2003 study, although the measured winds tended to be more turbulent (median k = 2.2 m 2 s −2 ) compared with JU2003 (median k = 0.45 m 2 s −2 ). Values for H ranged from 7.2 to 1186, with a median H of 80.9. The distribution of H was substantially wider for MID05 than for JU2003, with model estimates exceeding observations of H by an order of magnitude for single obstacle wind tunnel studies with Re ∼ 10 4 . Inverse relationships were validated between H and Re and between H and D / W for the MID05 data and for a pooled data analysis from the MID05 and JU2003 studies. The model of H vs. Re for pooled MID05 and JU2003 data provided a good fit overall but produced a positively biased estimate of the Oklahoma City model results. The model of H vs. D / W for pooled MID05 and JU2003 data did not provide a good fit, suggesting that the building topographies of the two cities are too different to produce a reasonable comparison. These inter-study comparisons suggest that the topographic relationships may contain underlying site-specific features that would require elucidation prior to generalizing to other urban sites. Overall, results from this work present a foundational method for generating estimates of H based on readily available sources of data such as building coordinates and dimensions and meteorological parameters.
Geologic Classification of Aquifers

This classification of aquifers is based upon the properties of rocks which affect ground water. In any region the rocks may be consolidated or unconsolidated. They may be uniform in lithology, or they may consist of alternating layers of different lithologies. They may have been tilted, fractured, or altered in various ways since their formation. Consequently the occurrence of ground water depends not only on the fundamental nature of the rocks but also on their geologic history. The ground water may be found under confined (artesian) or unconfined (water table) conditions. The permeability of an aquifer may be uniform, or it may vary in some regular way, or it may be very irregular because most of the water is in secondary openings. As most geologic situations do not fit well into precise categories, some aquifers may fall into more than one subdivision of this classification.
The Nature of Thermodynamic Coupling in Transport Processes

In considering problems of transport in biological systems, the definitive role of the numerous membranes as evidenced by electron microscopy (Robertson 1960, Palade 1964) is yet to be elucidated. These membranes appear to delineate not only the limits, of the individual cells, but indeed many of the subcellular structures as well. In an extremely complex fashion, membranes are involved in forming the cytoplasmic structure per se and are a prominent feature of the internal structure of subcellular elements. Attention in the past has been directed largely to those transport processes which are envisaged to occur transmembranally, that is across those barriers whose thickness is about 100 A. However, attention should also be directed to the possibility that such membranes may play a major role in defining and directing cytoplasmic fluid flow processes within the cell. Cytoplasmic circulation, known to occur in living cells, may well represent more than the random mixing and stirring of the cytoplasmic contents. It may be considerably more fundamental in relation to the detailed functioning of the cell. For instance, it is difficult to imagine how m-RNA, synthesized in the nucleus, could in its random-coiled state and moving by simple random diffusion, avoid becoming hopelessly entangled in the nuclear and cytoplasmic substructure. However, with actual fluid flow, a configurational alignment parallel to the lines of streaming is highly probable and, thus, transport could proceed efficiently from the presumed site of synthesis out through the pores of the nuclear membrane and to the sites of transcription on the endoplasmic reticulum. One may also readily envisage how cytoplasmic flow or micro-circulatory processes could play an important role in those cells engaged in the transport of materials from one bounding surface to another, such as renal tubular cells and those of the intestinal mucosa. In fact, as will be indicated below, the flow process could conceivably be intimately related to and involved in the work of concentration associated with active transport.
Pulse Switching for Static Event Sensing in Sensor Networks

This paper presents a novel energy-efficient pulse switching protocol for ultra light-weight wireless network applications. The key idea is to abstract a single pulse, as opposed to multi-bit packets, as the information exchange mechanism. Pulse switching is shown to be sufficient for event sensing applications with binary sensing. Event sensing with conventional packet transport can be prohibitively energy-inefficient due to the communication, processing, and buffering overheads of the large number of bits within a packet's data, header, and preambles. The paper presents a joint MAC-Routing architecture for pulse switching with a novel hop-angular event localization. Through simulation experiments, it is shown that pulse switching can be an effective means for event based networking, which can potentially replace the packet transport when the information to be transported is binary in nature.
Energy analysis for workshops with floor–supply displacement ventilation under the U.S. climates

Abstract Many studies have shown that floor–supply displacement ventilation systems are better than mixing ventilation systems. The benefits include indoor air quality, thermal comfort and reduced energy use. The energy benefits depend on the climate conditions. This research compared the energy use of a floor–supply displacement ventilation system in a large industrial workshop with that of a mixing ventilation system for five U.S. climate regions. It was found that the energy use and the system performance vary with the locations. The displacement ventilation system may use more fan and boiler energy but less chiller energy than the mixing ventilation system. The total energy used is slightly less with displacement ventilation, although the ventilation rate was increased in order to handle the high cooling loads found in U.S. buildings. Thus, the displacement ventilation system can save some energy in cooling mode. However, displacement ventilation system has a lower capacity of dehumidification. This system alone, thus, is not suggested for use in humid regions.
Femtosecond Pulse Propagation In Optical Fibers: Distortion And Nonlinear Chirping

Using computer simulations, we examine various factors affecting the propagation of femtosecond pulses in single-mode optical fibers in the wavelength range of normal dispersion. In particular, we show that distortion and nonlinear chirping of the pulse can arise from such con-siderations as initial pulse asymmetry, higher-order dispersion and nonlinearity effects in the fiber, and higher-order dispersion from optical components such as grating-pair compressors. The effect of initial pulse chirp is also examined. In addition, we investigate intensity-dependent spectra of these propagating pulses. Our results indicate that the addition of both the cubic-dispersion term and the so-called shock term in the nonlinear Schro-dinger equation generate intensity-dependent pulse spectra that compare well with experiments. We also show that asymmetry in the input pulse can be a contributing factor responsible for asymmetric spectra. Finally, we show how the use of additional optical components can be utilized to compensate for cubic phase distortion pulse, leading to a fuller utilization of the pulse bandwith and state-of-the-art pulse durations.
Flexure of Clamped Rectangular Plates Resting on Winkler Foundations

ABSTRACT The flexure under uniform load of clamped rectangular plates resting on elastic foundations is treated via eigenfunction expansions. The expansion coefficients are determined by expanding each of the nonorthogonal eigen-functions in terms of an orthogonal set of real functions. The numerical convergence of the associated eigenfunction expansions for some aspect ratios of the plate and some values of the foundation modulus are presented.
Four new mutations in the ornithine transcarbamylase gene.

Abstract We characterized four new mutations in the ornithine transcarbamylase (OTC) gene in three male infants who died from acute neonatal hyperammonemia and one male infant with late onset disease. OTC enzymatic activity was undetectable in the livers of the three neonates, whereas residual enzymatic activity was present in the fourth patient. All 10 exons of the OTC gene were amplified by the polymerase chain reaction (PCR) from genomic DNA of the four patients. The amplified DNA was screened for abnormal gel electrophoretic migration patterns via single-strand conformational polymorphism (SSCP). One patient showed an abnormal SSCP pattern of exon 8 and exon 9, a second patient had an abnormal exon 6, a third had an abnormal exon 9, and the fourth patient revealed an abnormal exon 3. Sequencing of the abnormal exons revealed that the first patient hod a deleterious mutation in exon 9 consisting of a G→T transversion in codon 310 causing a Glu→stop coding change. The abnormal exon 8 of this patient contained a common polymorphism consisting of an A→G transition in codon 270 resulting in Gln→Arg code change. The abnormal exon 6 of the second patient contained an A→G transition in codon 183 causing a Tyr→Cys change. Exon 9 of the third patient contained a deletion of a thymine nucleotide (base 882) resulting in a shift of the reading frame and a code for premature termination 28 codons downstream. The fourth patient with a "milder" clinical presentation had an A→T transversion in exon 3 (codon 88) causing a Lys→Asn change.
Effects of hyperventilation and hypoventilation on PaCO2 and intracranial pressure during acute elevations of intraabdominal pressure with CO2 pneumoperitoneum: large animal observations

Abstract Background: The side effects of acute elevations in intraabdominal pressure (IAP) are related to a multifactorial etiology. Previous studies have reported that acute elevations in IAP produce an immediate increase in intracranial pressure (ICP). This study was designed to analyze the reasons for increased ICP during acute elevations of IAP and to determine the combined effects of IAP and changes in ventilation indices on ICP and hemodynamic indices. Study Design: Five pigs were studied. A subarachnoid screw was placed for ICP monitoring. The jugular vein, femoral vein, and femoral artery were cannulated. Mean arterial pressure (MAP), central venous pressure (CVP), ICP, and arterial pressure of carbon dioxide (PaCO 2 ) were monitored before and after carbon dioxide pneumoperitoneum was established at 0, 10, and 20 mmHg of IAP. Effects of hyperventilation and hypoventilation were recorded and compared with baseline ventilation. Cavography was performed to evaluate the morphology of the inferior vena cava (IVC) at different levels of IAP. Multiple regression and Student's t -test were used to examine the effects of IAP and ventilation on dependent variables. Results: The IVC showed a progressive narrowing at the level of the diaphragm as IAP was increased. There was a simultaneous increase in CVP, MAP, and ICP. The mean changes in ICP with hypoventilation were significantly larger than with hyperventilation. Conclusions: Acutely increased IAP displaces the diaphragm cranially, narrowing the IVC and increasing intrathoracic pressure. This increases CVP and increases ICP by venous stasis and increased pressure in the sagittal sinus with decreased resorption of cerebrospinal fluid. Hemodynamic changes are directly related to the rise in ICP. Hypoventilation and hypercarbia significantly increase ICP when compared with hyperventilation and hypocarbia. Hyperventilation does not significantly decrease ICP during acute elevations of IAP.
Type II restriction endonucleases

Type II restriction endonucleases have emerged as important paradigms for the study of protein-nucleic acid interactions. This is due to their ability to catalyse phosphodiester bond cleavage with very large rate enhancements while also maintaining exquisite sequence selectivities. The principles and methods developed to analyze site-specific binding and catalysis for restriction endonucleases can be applied to other enzymes which also operate on nucleic acids. This paper reviews biochemical and structural approaches to characterization of these enzymes, with particular attention to the multiple crucial roles of divalent metal ions, the possibilities for use of alternative substrates in binding and catalytic experiments, the strategies for exploring the detailed chemistry of phosphoryl transfer, and the use of X-ray crystallography to provide descriptions of conformational pathways at specific, nonspecific, and noncognate DNA sites.
Results from the Deep Space 1 technology validation mission

Launched on October 25, 1998, Deep Space 1 (DS1) is the first mission of NASA's New Millennium Program, chartered to flight validate high-risk, new technologies important for future space and Earth science programs.