cssi/SciSciGPT-SciSciNet huggingface dataset:
Robots in Radiation Environments

Abstract Los Alamos National Laboratory has historically been involved with routine handling of a wide variety of hazardous materials. The majority of activities involve nuclear materials in projects ranging from medicinal uses to weapons technology development. The robotics development program at the Laboratory is primarily focused on identifying and automating operations that subject personnel to ionizing radiation, are repetitive, and are subject to human error. Development of automated technology for these operations will help meet national nuclear materials processing demands through the transfer of expertise gained at Los Alamos to other Department of Energy facilities. Robotic equipment that is compatible with glove box environments analytical instrument and in particular LC apparatus does not exist commercially, hence there is a need to design and/or modify systems that can tolerate environments encountered in Special Nuclear Material processing operations. Because of the interaction of atomic fis...
Source signature and elastic waves in a half-space under a momentary shear line impulse

The transient deformation of an elastic half-space under a line-concentrated impulsive vector shear load applied momentarily is disclosed in this paper. While in an earlier work, the author gave an analytical–numerical method for the solution to this transient boundary-value problem, here, the resultant response of the half-space is presented and interpreted. In particular, a probe is set up for the kinematics of the source signature and wave fronts, both explicitly revealed in the strained half-space by the solution method. The source signature is the imprint of the spatiotemporal configuration of the excitation source in the resultant response. Fourteen wave fronts exist behind the precursor shear wave S: four concentric cylindrical, eight plane, and two relativistic cylindrical initiated at propagating centres that are located on the stationary boundaries of the solution domain. A snapshot of the stressed half-space reveals that none of the 14 wave fronts fully extend laterally. Instead, each is enclosed within point bounds. These wave arresting points and the two propagating centres of the relativistic waves constitute the source signature. The obtained 14 wave fronts are further combined into 11 disparate wave fronts that are grouped into four categories: an axis of symmetry wave—so named here by reason of being a wave front that is contiguous to the axis of symmetry, three body waves, five surface waves and two inhibitor waves—so named here by reason that beyond them the material motion dies out. Of the three body waves, the first is an unloading shear wave, the second is a diffracted wave and the third is a reflected longitudinal two-branch wave. Of the two inhibitor waves, the first is a two-joint relativistic wave, while the second is a two-branch wave. The wave system, however, is not the same for all the dependent variables; a wave front that appears in the behaviour of one dependent variable may not exist in the behaviour of another. It is evident from this work that Saint–Venant's principle for wave propagation problems cannot be formulated. Therefore, the above results are valid for the particular proposed model for the momentary line-concentrated shear load. The formulation of the source signature, the wave system, and their role in the half-space transient deformation are presented here. Copyright © 2003 John Wiley & Sons, Ltd.
Looking at The World Through a Nastyglass Window

The concept and physics of a most peculiar glass (called NASTYGLASS) suffering from the video equivalent of audio cross-over distortion are discussed, and a simple mathematical model developed. The model is used as the basis for a computer simulation of how things would look when viewed through a NASTYGLASS window. Some computer-generated, TV-displayed images of `Einstein-in-NASTYGLASS' are included. Finally, future research is proposed, research that just might lead to a Nobel prize in medicine or physiology!
Nanoparticle Mass Transfer From Lung Airways to Systemic Regions—Part II: Multi-Compartmental Modeling

This is the second article of a two-part paper, combining high-resolution computer simulation results of inhaled nanoparticle deposition in a human airway model (Kolanjiyil and Kleinstreuer, 2013, "Nanoparticle Mass Transfer From Lung Airways to Systemic Regions--Part I: Whole-Lung Aerosol Dynamics," ASME J. Biomech. Eng., 135(12), p. 121003) with a new multicompartmental model for insoluble nanoparticle barrier mass transfer into systemic regions. Specifically, it allows for the prediction of temporal nanoparticle accumulation in the blood and lymphatic systems and in organs. The multicompartmental model parameters were determined from experimental retention and clearance data in rat lungs and then the validated model was applied to humans based on pharmacokinetic cross-species extrapolation. This hybrid simulator is a computationally efficient tool to predict the nanoparticle kinetics in the human body. The study provides critical insight into nanomaterial deposition and distribution from the lungs to systemic regions. The quantitative results are useful in diverse fields such as toxicology for exposure-risk analysis of ubiquitous nanomaterial and pharmacology for nanodrug development and targeting.
Troubles with Grades, Grading, and Change: Learning from Adventures in Alternative Assessment Practices in Teacher Education.

Abstract In this paper, two teacher educators work to understand their attempts to transform teacher–student relations by altering traditional grading practices. Using actor-network theory, the authors examine the social effects produced across and throughout a school of education when they changed the meaning and significance of grades. Detailed analysis of retrospective reflections (narratives and dialogue) reveals the deeply ingrained and broadly interconnected role that traditional understandings of grades play in defining and stabilizing identities and responsibilities. The specific outcomes here reveal the authors’ complicity in the failure of their own change effort and offer implications for teacher educators attempting change.
Chick vocal patterns and non-vocal stimulation as factors instigating parental feeding behaviour in the ring-billed gull

Abstract We have previously found that ring-billed gulls ( Larus delawarensis ) tending devocalized hatchlings fail to initiate a normal sequence of parental feedings. In this study, chick ‘peer’ or ‘distress’ calls were broadcast from beneath nests containing egg clutches or muted chicks. Both call patterns similarly induced parents to look downward or to rise and resettle, but only the peer call evoked repeated feedings of muted chicks. Feedings usually occurred during or shortly after broadcasts. Broadcasts of peer calls from beneath parents incubating eggs evoked some food presentations, but the overall rate was low. These same parents later showed no enhanced posthatching feeding rate. The results indicate that parents require auditory reception of peer calls, augmented by visual and/or tactile input from active chicks, to initiate normal posthatching food provisioning. This provisioning does not depend on or seem enhanced by prior exposure to calls of foetal chicks.
Sub-diffraction Optical Imaging by High-spatial-resolution photodetectors and Fourier Signal Processing

With the advance of nano-lithography and nano-fabrication, individual sizes of electronic, photonic, and mechanical components, as well as their integration densities, have progressed steadily towards the sub-100 nm regime. Therefore, being able to image such feature sizes becomes imperative. Many conventional high-resolution imaging tools such as SEM, STM, AFM, and NSOM either require operation under high vacuum or slow scanning across the sample. A far-field optical imaging instrument would thus be highly desirable. Optical imaging, however, is subject to the diffraction limit, which limits the size of the smallest resolvable feature to be ~ λ/2, where λ is the wavelength of the imaging light. Recently, negative-index materials and super lens have been proposed to overcome this limit and achieve high-resolution optical imaging [1-4]. In this paper, we propose a different approach to achieve sub-diffraction optical imaging with far-field microscopy. The technology builds on a high-spatial resolution quantum-dot (QD) photodetector with high sensitivity that we have demonstrated [5]. The photodetector consists of several nanocrystal QDs between a pair of electrodes with 50-nm width spaced ~ 25 nm apart. An optically effective area of 13515 nm 2 was determined by modeling the electric field distribution in-between and around the electrodes using FEMLab. High-sensitivity photodetection has been demonstrated by measuring the tunneling photocurrent through the QDs, with a detection limit of 62 pW of the input optical power. The proposed sub-diffraction optical imaging system consists of an array of such photodetectors. We performed theoretical simulations assuming a two slit source and then pixilated the far-field diffraction pattern to simulate the photodetector array. A Fourier transform of the detector signal is then performed to determine how much of the original aperture information remains. Using a wavelength of 500 nm and a screen distance of 10 cm, we found that, as expected, the quality of the resultant image generally degraded with larger pixilation size. With 50-nm one-dimensional spatial resolution at the detection plane, it appears that the original slit image with 100-nm width and 300-nm spacing can still be restored.
Evidence for localized ductile fracture in the “brittle” transgranular stress corrosion cracking of ductile F.C.C. alloys

Abstract Experimental evidence, obtained using scanning and transmission electron microscopy, is presented which demonstrates clearly that the transgranular stress corrosion cracking (TGSCC) of α-brass (Cu-30 Zn) in cupric ammonia solutions occurs by extremely localized ductile fracture as opposed to any of the many other mechanisms proposed in the literature. In addition, supporting evidence is given for TGSCC in other f.c.c. alloys (AlZnMg in aqueous NaCl and Type 304 stainless steel in aqueous MgCl2). Based on the results, a mechanism whereby local anodic dissolution leads to such failures is presented and an attempt is made to explain many of the apparently conflicting results published previously for cracking in these important alloy systems.
Sociolinguistic analysis: Nonformalassessment of children's language and literacy skills

The focus of this special issue of the journal is upon nonformal assessment of children'slanguage and literacy skills in school. Each of the authors of this isse shares the view that the traditional methods of testing and evaluation of children's competencies have not adequately contributed to the improvement of children's leaning in shool. In particular, formal standardized testing has failed nonmajority children. The research preseted in this issue clearly illustrates the inadequacies of solely relying on standardized testing to obtain a complete view of children's competencies. This article provides an overview for the three research articles presented in thisissue. It includes a discussion of sociolinguistic approaches to assessment and a comprehenvise view of multiple methods of assessment as applied to observation of children's language use in school. The conclusion considers the consequences of inadequate assessment for school failure.
Kinetics of Vacancy-Interstitial Annihilation. I. Impurity-Interstitial Trapping

The equations for the kinetics of vacancy-interstitial annihilation with interstitial trapping at impurities have been solved in closed form. Although the transients are given by rather complex combinations of exponentials the later part of the decay is simple quadratic. This quadratic decay is governed by the decomposition of the interstitial-impurity complex. The effective activation energy is the sum of the interstitial migration energy and its binding energy to the impurity.
The effect of the amount of blood in a violent video game on aggression, hostility, and arousal

Abstract The current study utilized the General Aggression Model, with an emphasis on aggression-related priming, to explore the different effects on hostility, physiological arousal, and state aggression in those who played a violent video game ( Mortal Kombat: Deadly Alliance ) with differing levels of blood (maximum, medium, low, and off). Simple effects analyses showed that those in the maximum blood and medium blood conditions had a significant increase in hostility and physiological arousal, while those in the low blood and no blood conditions did not have such an increase in arousal and hostility. Further analyses indicated that those in the maximum and medium blood conditions used the character’s weapon significantly more often than those in the low and blood absent conditions. Implications and future research are discussed.
Whose right to (farm) the city? Race and food justice activism in post-Katrina New Orleans

Among critical responses to the perceived perils of the industrial food system, the food sovereignty movement offers a vision of radical transformation by demanding the democratic right of peoples “to define their own agriculture and food policies.” At least conceptually, the movement offers a visionary and holistic response to challenges related to human and environmental health and to social and economic well-being. What is still unclear, however, is the extent to which food sovereignty discourses and activism interact with and affect the material and social realities of the frequently low-income communities of color in which they are situated, and whether they help or hinder pre-existing efforts to alleviate hunger, overcome racism, and promote social justice. This research and corresponding paper addresses those questions by examining food justice and food sovereignty activism in the city of New Orleans since Hurricane Katrina as understood by both activists and community members. I argue, using post-Katrina New Orleans as a case study, that food projects initiated and maintained by white exogenous groups on behalf of communities of color risk exacerbating the very systems of privilege and inequality they seek to ameliorate. This paper argues for a re-positioning of food justice activism, which focuses on systemic change through power analyses and the strategic nurturing of interracial alliances directed by people residing in the communities in which projects are situated.
Psychological needs and verbally expressed aggression of adolescent delinquent boys

(1966). Psychological Needs and Verbally Expressed Aggression of Adolescent Delinquent Boys. The Journal of Psychology: Vol. 62, No. 2, pp. 179-194.
A Monte Carlo simulation approach for generating NaI detector response functions (DRFs) that accounts for non-linearity and variable flat continua

Abstract A new approach to generating detector response functions (DRFs) for NaI detectors is developed and demonstrated. It consists of using Monte Carlo simulation with a specific purpose code (named g03) that utilizes relatively rigorous gamma-ray transport with very simple electron transport. The approach accounts for two phenomena that have not been previously treated in this way: NaI non-linearity and the variable flat continua part of the DRF. The first is accounted for by utilizing the known non-linear relationship between NaI scintillation efficiency and deposited electron energy within the Monte Carlo code. The second is accounted for by using a semi-empirical relationship between electron range and incident gamma-ray energy within the Monte Carlo code. The resulting DRFs for 3 ″ × 3 ″ and 6 ″ × 6 ″ NaI detectors are benchmarked with the extensive existing data of Heath [AEC Research and Development Report, Physics, TID-4500] for the 3 ″ × 3 ″ detectors and with new data for the 6 ″ × 6 ″ detectors. Results indicate that the approach is accurate and the use of this approach should increase the accuracy of prompt gamma-ray neutron activation analysis significantly.
V3Si formation by the bronze process

Previous studies of the reaction between V and Cu(Si) solid solutions have reported that the V3Si layers formed are much thinner than the accompanying V5Si3 layers. We have found that, although V5Si3 layers are formed for matrix compositions at least as low as 1 at. % Si, the proportion of V3Si produced increases as the Si concentration in the matrix decreases. Furthermore, if the total proportion of Si to V in the composite is kept sufficiently low, the V5Si3 formed is eventually converted to V3Si. Results are discussed in terms of a proposed partial Cu-V-Si phase diagram.
Predictors of Parental Accommodation in Pediatric Obsessive-Compulsive Disorder: Findings from the Pediatric Obsessive-Compulsive Disorder Treatment Study (POTS) Trial

Objective Few studies have examined predictors of parental accommodation (assessed with the Family Accommodation Scale–Parent Report) among families of children with obsessive-compulsive disorder (OCD). No studies have examined this phenomenon using empirically derived subscales of the Family Accommodation Scale–Parent Report (i.e., Caregiver Involvement, Avoidance of Triggers). Method Ninety-six youths (and their families) were included in the present study. Parents were asked to complete the Family Accommodation Scale–Parent Report. Families also completed several additional measurements assessing child- and parent-level variables of interest. Regression analyses were used to examine potential predictors of accommodation. Results Results support prior research suggesting that accommodation is ubiquitous among the families of children with OCD. Analyses revealed that several child-level (i.e., compulsion severity, oppositional behavior, and frequency of washing symptoms) and one parent-level (i.e., symptoms of anxiety) predictors work jointly to provide significant predictive models of parental accommodation. Conclusions Clinicians and researchers should be aware of the impact of specific child- and parent-level variables on family accommodation in pediatric OCD and in turn their implications for treatment compliance, adherence, and, by extension, outcome. Study limitations warrant replication and extension of these findings; in particular, researchers may seek to obtain a better understanding of how the various facets of parental accommodation may differentially affect treatment.
Performance and metabolic responses of young dairy calves fed diets supplemented with chromium tripicolinate

Forty-two Holstein calves were used to study performance and metabolic responses when milk replacer and then postweaning starter were supplemented with 1 ppm of Cr as Cr-tripicolinate. From birth through 8 wk of age, supplemental Cr tended to improve the growth performance of bull calves but not of heifer calves. Starter intake and feed efficiency were not affected by supplemental Cr. From 1 to 5 wk of age, plasma cortisol concentrations sampled just prior to feeding decreased, and concentrations of insulin-like growth factor-I increased. All calves appeared to become less sensitive to insulin as they aged. From 1 to 5 wk of age, plasma glucose and insulin concentrations gradually diverged for all calves; glucose concentrations decreased, and insulin concentrations increased. In addition, glucose clearance rate, measured by i.v. glucose tolerance tests, was more rapid when calves were 2 wk of age than when calves were 8 wk of age. The glucose clearance rate was greater in heifer calves than in bull calves but was not affected by supplemental Cr. Entry of plasma glucose following an i.v. propionate load was also greater in heifer calves than in bull calves but was not affected by supplemental Cr. Plasma nonesterified fatty acids were lower in calves fed milk replacer or starter supplemented with Cr than in control calves, although this effect diminished as calves aged. This finding was considered to be indirect evidence of enhanced insulin sensitivity in calves fed milk replacer or starter supplemented with Cr. Overall, data suggested that supplemental Cr-tripicolinate had minor effects on the metabolism and growth performance of conventionally managed dairy calves. The most notable effects occurred during the initial few weeks of life.
The global structure of upper troposphere‐lower stratosphere ozone in GEOS‐5: A multiyear assimilation of EOS Aura data

Eight years of ozone measurements retrieved from the Ozone Monitoring Instrument and the Microwave Limb Sounder, both on the EOS Aura satellite, have been assimilated into the Goddard Earth Observing System Version 5 (GEOS-5) data assimilation system. This study evaluates this assimilated product, highlighting its potential for science. The impact of observations on the GEOS-5 system is explored by examining the spatial distribution of the observation-minus-forecast statistics. Independent data are used for product validation. The correlation of the lower stratospheric (the tropopause to 50 hPa) ozone column with ozonesondes is 0.99 and the (high) bias is 0.5%, indicating the success of the assimilation in reproducing the ozone variability in that layer. The upper tropospheric (500 hPa to the tropopause) assimilated ozone column is about 10% lower than the ozonesonde column, but the correlation is still high (0.87). The assimilation is shown to realistically capture the sharp cross-tropopause gradient in ozone mixing ratio. Occurrence of transport-driven low ozone laminae in the assimilation system is similar to that obtained from the High Resolution Dynamics Limb Sounder (HIRDLS) above the 400 K potential temperature surface, but the assimilation produces fewer laminae than seen by HIRDLS below that surface. Although the assimilation produces about 25% fewer occurrences per day during the 3 years of HIRDLS data, the interannual variability is captured correctly. This data-driven assimilated product is complementary to ozone fields generated from chemistry and transport models. Applications include study of the radiative forcing by ozone and tracer transport near the tropopause.
Segmentation and linguistic summarization of voxel environments using stereo vision and genetic algorithms

For reasons such as computational complexity, spatial and temporal information reduction, and human understandability, it is important that computer vision systems be equipped with the means to summarize their content in a natural language. Such rich descriptions are of use by both humans and computers for describing, recognizing, and tracking objects, activity, and their interactions at a desired level of abstraction. A genetic algorithm is introduced here for segmenting non-human objects deemed relevant to human activity analysis in stereo vision acquired voxel environments. This approach is of use in an Eldercare setting as it relates to monitoring the “well-being” of residents through acquiring and detecting deviations in patterns of typical behavior as well as recognizing abnormal events, such as fall detection.
Large Differences between Partial Correlation Coefficients

It is well known that the value of a partial correlation coefficient need not be close to the value of the correlation coefficient. Kendall and Stuart (1961) and Fisher (1958) give examples of this fact. The following example shows a strong reversal between a correlation coefficient and a partial correlation coefficient. An explanation for this reversal and a practical application are given. For artificial fibers, such as nylon and polyester, two important physical properties are tenacity and elongation. Tenacity is a measure of the stress that is applied to the fiber by a tensile machine:
Role of the phosphatase PhoX in the phosphorus metabolism of the marine bacterium Ruegeria pomeroyi DSS‐3

Summary Marine microbes are adapted to surviving in a vari- able phosphorus (P) environment. This adaptation frequently involves the presence of periplasmic or cell membrane-associated enzymes that enable them access to alternative sources of P when phosphate is depleted. In a recent study we identified the phos- phatase PhoX as an enzyme that may be essential in mediating organic P acquisition in the ocean. Here we have investigated the role of this enzyme in the utili- zation of different P sources, using as a model the marine bacterium Ruegeria pomeroyi DSS-3. Although our previous study had demonstrated that PhoX accounts for more than 90% of the alkaline phosphatase (APase) activity in R. pomeroyi, a PhoX mutant strain was able to grow on monophosphate esters at the same rate as the wild type. Nevertheless, further APase kinetic analyses with both strains dem- onstrated that the Km of the wild-type strain was an order of magnitude lower than the mutant strain, indicating that PhoX is crucial for the use of these substrates at low concentrations, typically found in seawater. We also showed that PhoX is required for efficient hydrolysation of nucleotides like ADP and ATP.
Quantifying aquatic insect deposition from lake to land

Adjacent ecosystems are influenced by organisms that move across boundaries, such as insects with aquatic larval stages and terrestrial adult stages, which transport energy and nutrients from water to land. However, the ecosystem-level effect of aquatic insects on land has generally been ignored, perhaps because the organisms themselves are individually small. At the naturally productive Lake Mývatn, Iceland, we used two readily measured quantities: total insect emergence from water and relative insect density on land, to demonstrate an approach for estimating aquatic insect deposition (e.g., kg N·m−2·yr−1) to shore. Estimates from emergence traps between 2008 and 2011 indicated a range of 0.15–3.7 g·m−2·yr−1, or a whole-lake emergence of 3.1–76 Mg/yr; all masses are given as dry mass. Using aerial infall trap measurements of midge relative abundance over land, we developed a local-maximum decay function model to predict proportional midge deposition with distance from the lake. The dispersal model predicted midge abundance with R2 = 0.89, a pattern consistent among years, with peak midge deposition occurring 20–25 m inland and 70% of midges deposited within 100 m of shore. During a high-midge year (2008), we estimate midge deposition within the first 50 m of shoreline to be 100 kg·ha−1·yr−1, corresponding to inputs of 10 kg N·ha−1·yr−1 and 1 kg P·ha−1·yr−1, or about three to five times above background terrestrial N deposition rates. Consistent with elevated N input where midges are most dense, we observed that soil available nitrate in resin bags decreases with increasing distance from the lake. Our approach, generalizable to other systems, shows that aquatic insects can be a major source of nutrients to terrestrial ecosystems and have the capacity to significantly affect ecosystem processes.
Theoretical aspects of hybrid chiral bag models

In hybrid chiral bag models (HCBM's) the quarks are the source for the pion field outside the bag. If we want to solve this model with a classical external soliton solution and quantized fermions, it is necessary to evaluate the vacuum expectation values (VEV's) of those operators that contain fermion fields and appear in the boundary conditions. When the external solution is the so-called hedgehog solution, pi-arrow-right(r,t) = f/sub ..pi../theta(r)r, the relevant VEV is where eta is a cutoff parameter (eta..-->..0). To obtain this result we have used a multiple-reflection expansion of the Green's function, while C/sub 0/(theta) is evaluated numerically. We discuss the infinite contribution in the above VEV, and show that 4..pi..C/sub 0/(theta)/R is precisely the derivative of the Casimir energy with respect to theta. We also discuss some solutions of the HCBM for bag radii varying from 0 to infinity.
Extension of a full-wave layered interconnect simulator (UA-FWLIS) to handle lossy interconnects

In this paper, we discuss the enhancement of a MoM-based full-wave layered interconnect simulator (UA-FWLIS) so that it can handle conductor losses. By introducing an effective surface current and a surface impedance, the losses on the interconnects can be easily included in UA-FWLIS by adding an extra term to the reaction elements. Thus, the approach for analytically calculating the integrals in the reaction matrix, which uses readily computable ILHIs and residue theory, is still valid and the efficiency of UA-FWLIS can be retained. Comparing the S-parameter results from UA-FWLIS with those from Agilent Momentum validates the accuracy of the enhanced UA-FWLIS.
Expression and Kinetic Characterization of Methylmalonyl-CoA Mutase from Patients with the Mut− Phenotype: Evidence for Naturally Occurring Interallelic Complementation

L-Methylmalonyl-CoA mutase (MUT) is an adenosylcobalamin (AdoCbl)-requiring mitochondrial matrix enzyme that catalyzes the isomerization of L-methylmalonyl-CoA to succinyl-CoA. Inherited defects in the gene encoding this enzyme result in the mut forms of methylmalonic acidemia. Expression of mature human MUT cDNA in Escherichia coli at a post-induction cultivation temperature of 12 degrees C, rather than 37 degrees C, led to the folding of the majority of the synthesized protein to a soluble form, with an activity of 0.2-0.3 U/mg protein in the cell-free extract, 10-15 times higher than that in human liver homogenate. Six missense mutations, producing the amino acid changes G94V, Y231N, R369H, G623R, H678R and G717V, were detected in MUT cDNA of patients suffering from the mut- form of methylmalonic acidemia, resulting from defective AdoCbl binding. Two (G623R and G717V) had been reported in other patients. Three (G94V, Y231N and R369H) are the first changes in the NH2-terminal part of the enzyme reported to cause the mut- phenotype. Enzymes with the mutations were individually expressed, and their kinetic parameters were generally in accord with published biochemical data from extracts of fibroblasts from these patients. The mutations increased the K(m) for AdoCbl by 40- to 900-fold, while V(max) values varied from 0.2% to nearly 100% of that of wild-type protein. In one case of a doubly heterozygous cell line, however, neither of the constituent mutant enzymes had a K(m) corresponding to the lower of the two estimated from the extract data. This finding may reflect the natural occurrence of interallelic complementation in vivo in this cell line.
Sexual behavior and risk perceptions related to HIV infection among college students

Purpose To assess behavioral determinants (sexual behavior stage, partner numbers, partner types, condom use, and sexual orientation) on risk perceptions related to HIV infection among college students. HIV risk perception has been shown to be significantly related to prior HIV testing behavior; however, current knowledge of determinants related to HIV risk perceptions among college students has been limited. Understanding how behavior risk factors influencing HIV risk perception can play a critical role for developing effective HIV prevention and education programs. Methods A Web-based survey was administered during spring 2003 at one of the major universities in the southeastern United States. Results A total of 440 college students participated in the study: mean age 21 (SD = 2.48), 75% female, 88% heterosexual. Mean of the “perceived risk of HIV” scale (3-item), rated on five-point Liker scale, was used to classify students into low versus high risk perception groups (mean = 6.40). Sexual behavior stage index grouped students as “no to any sex” (16.7%), “yes to oral sex only” (17.2%), “yes to both oral and vaginal sex” (43.0%), and “yes to oral and (vaginal) and anal sex” (23.2%). Logistic regression, with sexual behavior stage index, number of partner index (oral + vaginal + anal), types of partner index (someone as injection drug user, with multiple partners, or paid for sex), condom use index, and sexual orientation as independent variables, was used to predict HIV risk perception. Results indicated that the full model of the combined five predictors was statistically reliable in distinguishing between students with high versus low risk perception (X(5) = 23.162, P Conclusion Despite risky sexual behaviors prevalent among college students, the overall perception of HIV infection was low. Results suggest that educational messages addressing the number of partners and its relationship with actual risk of HIV infection could be an effective strategy to increase risk perception.
ALIGNMENT OF SUN, EARTH, AND SATELLITE

Abstract : The results are reported of an investigation of the relations among the launch parameters of an earth satellite and the time and position of alignment of the sun, the earth, and the satellite. The effects of variations of the launch conditions upon the satellite's time of transit across the solar disc are determined. (Author)
Miniature mass spectrometers

We discuss miniaturization in mass spectrometry in terms of the mass analyzer, the mass spectrometer, and the total analytical system. Mass analyzer miniaturization has focused on ion traps. Decreases in mass analyzer size facilitate reduction of the sizes of the other components of a miniature mass spectrometer, especially the radio frequency electronics and vacuum system. Appropriate sample introduction systems are needed for performance optimization. The criteria by which a miniature mass spectrometer is judged include adequate performance in the traditional areas of resolution, detection limits, and specificity; ruggedness; reliability; and fully autonomous operation. Our discussion of the total analytical system emphasizes the removal of the bottleneck of sample preparation and suggests a solution to the combination of sampling, preconcentration, and ionization: ambient ionization methods. We also describe current miniature mass spectrometers.
Deltaic Sedimentation in Nacatoch Formation (Late Cretaceous), Northeast Texas: ABSTRACT

The terrigenous clastics of the Nacatoch Formation are a record of short-lived progradational phases within the major Late Cretaceous transgression in the East Texas embayment. Progradation was achieved by deltaic out-building from three fluvial feeder systems along the north and northwest margins of the basin. It is probable that additional sediment was derived from a major "sediment dispersal system" east of the Nacatoch deltas. The deltaic package of the Nacatoch (131 m, 430 ft) is composed of roughly equal proportions of sandstones and mudstones, with the sandstones ranging from very fine-grained, poorly sorted, and mud-rich, to fine-grained and well-sorted. The sandstones have a feldspathic litharenite and subfeldspathic litharenite composition with increasing compositional maturity in the well-sorted examples. Some of the muddy sandstones are highly bioturbated and carbonaceous. Vertical and lateral lithofacies changes in the Nacatoch deltas were determined by means of electric-log (resistivity) interpretation and well core data, with support from limited outcrop studies. Dip- and strike-oriented cross sections delineated three major coarsening-upward sandstone units which could be correlated in a shore-parallel direction for 42 km (25 mi). Each sandstone shows evidence of reworking by wave-induced processes and redistribution by longshore currents. The lower two sandstones are separated by a thick mudstone interval interpreted as a minor transgressive event. The highly bioturbated, carbonaceous, mud-rich intervals between the other sandstone units are interdistributary bay fills. The Nacatoch deltas are lobate and developed in response to moderate sediment input, moderate to low wave-energy flux, and significant longshore current action. Southwest longshore sediment transport from the Nacatoch deltas gave rise to extensive shelf sands in the western margin of the East Texas basin. These well-sorted sandstones are petroleum reservoirs at shallow depths. The similar well-sorted sandstones of the Nacatoch deltas have the same potential as petroleum reservoirs, given the same structural influence. End_of_Article - Last_Page 496------------
Atmospheric Processes Influencing Aerosols Generated by Combustion and the Inference of Their Impact on Public Exposure: A Review

Combustion-generated aerosols, especially emissions of heavy and light duty vehicles, are the dominant contributors of ambient particulate matter (PM) in urban environments. This paper reviews the atmospheric processes (such as dilution, nucleation, condensation and coagulation) that dominate the dynamics of combustion aerosols following their emission, with a particular emphasis on PM from mobile sources. Atmospheric dilution affects the dynamic behavior of aerosols by shifting the gas-particle partitioning of the semi-volatile component of these aerosols. Our paper discusses the roles of dilution in changing the physico-chemical properties of the ambient aerosols, such as particle size distribution and number concentration, and the degree to which it affects non-labile and semi-volatile PM components. This information is complemented with a discussion of secondary aerosol formation from atmospheric photochemical reactions that involve precursors emitted from traffic sources. Special focus is devoted to the role of gas-phase vapors formed from the evaporation of the semi-volatile fraction of aerosols during dilution. Adding to the common recognition that volatile organic compounds (VOCs) are the major gaseous precursors, these vapors also actively participate in photochemical reactions and contribute to the formation of secondary aerosols. Following this discussion, we review recent findings that link PM semi-volatile components and their redox activity, and we discuss the influence and importance of PM volatility on particle toxicity. Lastly, this paper discusses possible metrics to regulate PM emissions and establish ambient air quality standards that are pertinent to public health, and suggests future investigations aimed to improve our current understanding of the adverse health effects of population exposure to combustion-generated aerosols.
Low-Voltage Double-Gate ZnO Thin-Film Transistor Circuits

In this letter, we report double-gate ZnO thin-film transistor (TFT) circuits deposited by plasma-enhanced atomic layer deposition that are suitable for low-voltage operation. Compared to bottom-gate-only ZnO TFTs, double-gate ZnO TFTs have improved mobility, subthreshold slope, and bias stability. In this letter, the TFT top gate is used to adjust the bottom-gate turn-on and threshold voltage. This allows the logic transition point for circuits to be adjusted for operation at a low voltage. Using this approach, high-gain inverters (gain >100) and low-voltage ring oscillators using double-gate TFTs have been demonstrated. Double-gate inverters with a beta ratio of 5 have a gain larger than 100. Fifteen-stage double-gate ZnO TFT ring oscillators operate with VDD = 1.5 V, ID = 28 μA, and propagation delay of 2 μs per stage.
Interaction of protamine sulfate with thrombin

Protamine sulfate (salmine), a basic protein with a molecular weight of 4,626 +/- 109, is a known antiheparin agent which in the absence of heparin demonstrates an anticoagulant activity. To date, much work has been done to elucidate the interaction of heparin with thrombin and its physiologic inhibitor, Antithrombin III (ATIII). Little is known, however, about the mechanism of anticoagulant action of protamine sulfate and its mode of thrombin inactivation. We provide information about the interaction of protamine sulfate with purified, labeled thrombin and ATIII through binding experiments in which protamine is shown to inhibit the inactivation of thrombin by ATIII. Furthermore, we show in clotting assays that protamine sulfate has an inhibitory effect on thrombin in the conversion of fibrinogen to fibrin, and that this inhibition is concentration dependent, partial, and reversible.
Combining Graphics and a Layout Language in a Single Interactive System

Layout languages provide users with the capability to algorithmically define cells. But the specification language is so non-intuitive that it is impossible to debug a design in that language, one must plot it. Interactive graphics systems, on the other hand, allow the user to debug in the form in which he sees the design, but severely restrict the language he may use to express the graphics. For example, he cannot express loops or conditionals. What is really needed is a single interactive system that combines layout language and graphic modifications to the data. This paper describes just such a system.
Kansas energy, environment, and conservation: a geological overview

The State of Kansas, as an energy-producing and agriculture-based state, faces problems in production of natural resources and potential pollution from their production. To coordinate information on the exploration, production, and use of coal, nuclear, petroleum, natural gas, hydro, wind, geothermal, coalbed methane, biofuel, solar, and other energy resources, the Kansas Energy Council and the University of Kansas Energy Research Center were created. Water, surface and subsurface, is the other important and maybe the most important natural resource in the welfare of the state. To ease the problems of contamination, situations are monitored by regulatory agencies: the Kansas Corporation Commission, Kansas Department of Health and Environment, and Division of Water Resources of the Kansas Department of Agriculture. The Kansas Geological Survey (KGS) at the University of Kansas serves as the archive for energy and natural resource data and conducts research pertinent to the exploration and exploitation of mineral resources, including energy and water. The Kansas Energy Research Center coordinates and supports energy activities. The Kansas Water Office and the staff for the Kansas Water Authority are charged with water planning and preparing reports on water problems and possible solutions. The cost of preserving the environment in a relatively pristine state really is of no concern considering the possible consequences; living conditions should be preserved to assure future generations, a suitable, sustainable, stable environment. With all the dire predictions for the future and energy-producing and pollution problems, Kansas is a model state in this modern industrial age for protecting the environment and is a leader in conservation.
Somatic Hypermutation Introduces Insertions and Deletions into Immunoglobulin V Genes

During a germinal center reaction, random mutations are introduced into immunoglobulin V genes to increase the affinity of antibody molecules and to further diversify the B cell repertoire. Antigen-directed selection of B cell clones that generate high affinity surface Ig results in the affinity maturation of the antibody response. The mutations of Ig genes are typically basepair substitutions, although DNA insertions and deletions have been reported to occur at a low frequency. In this study, we describe five insertion and four deletion events in otherwise somatically mutated VH gene cDNA molecules. Two of these insertions and all four deletions were obtained through the sequencing of 395 cDNA clones (∼110,000 nucleotides) from CD38+IgD− germinal center, and CD38−IgD− memory B cell populations from a single human tonsil. No germline genes that could have encoded these six cDNA clones were found after an extensive characterization of the genomic VH4 repertoire of the tonsil donor. These six insertions or deletions and three additional insertion events isolated from other sources occurred as triplets or multiples thereof, leaving the transcripts in frame. Additionally, 8 of 9 of these events occurred in the CDR1 or CDR2, following a pattern consistent with selection, and making it unlikely that these events were artifacts of the experimental system. The lack of similar instances in unmutated IgD+CD38− follicular mantle cDNA clones statistically associates these events to the somatic hypermutation process ( P = 0.014). Close scrutiny of the 9 insertion/deletion events reported here, and of 25 additional insertions or deletions collected from the literature, suggest that secondary structural elements in the DNA sequences capable of producing loop intermediates may be a prerequisite in most instances. Furthermore, these events most frequently involve sequence motifs resembling known intrinsic hotspots of somatic hypermutation. These insertion/deletion events are consistent with models of somatic hypermutation involving an unstable polymerase enzyme complex lacking proofreading capabilities, and suggest a downregulation or alteration of DNA repair at the V locus during the hypermutation process.
Reflections on the History of the Family: A Review Essay

It is, I trust, no longer necessary to defend the inclusion of family life among the proper concerns of historical scholarship. Work on the subject has been accumulating for about a decade, and from all indications the trend will accelerate in the near future. Still, the sum of the results to date is relatively modest. As with any new field of research, many of the outer boundaries and much of the internal topography remain to be explored. So far a single line of research has been notably-almost exclusivelydominant. I mean, of course, the demographic one. Beginning with the work of the 'sixieme section' in France, and ably followed by the members of the Cambridge (England) Group for the Study of Population and Social Structure, a broad range of ingenious techniques has been developed for the statistical analysis of families in pre-modern Europe. More recently, the movement has crossed the ocean, and already a new generation of historical demographers is busy with similar materials from the American past. Because, however, the achievements of this research are so tangible, and also because the methodology is so dazzling, there is danger of a certain loss of intellectual balance. Too often nowadays scholars refer to the history of the family as if it comprised the demographic history of the family, and little more. The shortsightedness of this perspective will be immediately acknowledged, but the problem is a real one nonetheless. This is not to belittle the place of demography in the study of the family. Such work has been, and will continue to be, of undeniable importance. Indeed it was especially important in the initial phase of this inquiry: one had to know the statistical contours of pre-modern families before one could deal adequately with their structural and psychological elements. Thus the distribution of power between spouses has depended, in part, on their respective ages at marriage. Patterns of inter-generational contact
Who Cares? The Role Of Job Involvement In Psychological Contract Violation

This study examined survey data from full-time employees employed in a variety of occupations. We empirically examined how psychological involvement with one's job affects reactions to psychological contract violation. Data for control variables (i.e., age, gender, organizational tenure), the independent variable (i.e., psychological contract violation), and the moderator (i.e., job involvement) were taken at Time 1; and dependent variables (i.e., depressed mood at work, turnover intention) were taken at Time 2. Results illustrated that job involvement was an important construct in understanding individuals' negative reactions to psychological contract violations. Implications and limitations are discussed, and suggestions for future research are offered.