cssi/SciSciGPT-SciSciNet huggingface dataset:
Knowledge and Perceptions of Tobacco-Related Harm Associated with Intention to Quit among Cigarette Smokers, e-Cigarette Users, and Dual Users: Findings from the US Population Assessment of Tobacco and Health (PATH) Wave 1.

To study the association between knowledge of diseases caused by smoking, perceptions of harm of cigarettes and intention to quit among cigarettes and e-cigarettes users. Methods: Using US Populati...
Guanylyl Cyclase Genes and Their Role in Retinal Degeneration

Guanylyl cyclases play a fundamental role in a wide variety of cellular processes. In response to specific regulatory signals these enzymes form the intracellular second messenger molecule cGMP. In vertebrate retinal photoreceptor cells cGMP has been identified as the primary internal messenger for visual transduction more than a decade ago. Inherited defects in cGMP metabolism have been linked to retinal degeneration and blindness even longer. Recently, specific gene defects in one of the retinal isoforms of guanylyl cyclase, RETGC-1, have been found to cause Leber’s congenital amaurosis (LCA) and an autosomal-dominant form of cone-rod dystrophy. We investigated the functional consequences of a RETGC-1 missense mutation (F589S) described in LCA patients. We demonstrate that this mutation markedly decreases enzyme activity when expressed in vitro. Function and possible linkage to eye disease of an X-chromosomal gene encoding a second retinal isoform, RETGC-2, are less clear. We determined the genomic structure of RETGC-2 as a prerequisite for future mutation screening studies.
NSA's MISSI Reference Architecture - Moving from Prose to Precise Specification

We discuss the definition and modeling of reference of architectures, and the notion of conformance. NSA’s MISSI (Multilevel Information System Security Initiative) security reference architecture is used as an illustrative example.
Introduction to Linear Algebra

Linear algebra is something all mathematics undergraduates and many other students, in subjects ranging from engineering to economics, have to learn. The fifth edition of this hugely successful textbook retains the quality of earlier editions while at the same time seeing numerous minor improvements and major additions. The latter include: a new chapter on singular values and singular vectors, including ways to analyze a matrix of data; a revised chapter on computing in linear algebra, with professional-level algorithms and code that can be downloaded for a variety of languages; a new section on linear algebra and cryptography; and a new chapter on linear algebra in probability and statistics. A dedicated and active website also offers solutions to exercises as well as new exercises from many different sources (e.g. practice problems, exams, development of textbook examples), plus codes in MATLAB, Julia, and Python.
Abstract 153: Motor Imagery During Movement Activates the Brain More Than Movement Alone After Stroke

Introduction: Task-oriented training is a key component of many stroke rehabilitation programs. Motor imagery activates movement execution circuits as well as brain areas related to cognitive aspects of movement training, such as planning or functional relevance. Movement execution and imagery might work synergistically in activating the motor system after stroke, but to date have only been studied separately. The current study examined the neural correlates of imagery in conjunction with execution, hypothesizing that the combined approach would increase brain activation in areas important to movement training. METHODS: Seven patients with chronic right hemiparetic stroke were studied, with age 55.1±.3 years (mean±SD), 13.1±12.8 mo post-stroke, and arm motor Fugl-Meyer score 50.9±11.9. Each performed a paretic arm pronation/supination task under 2 conditions during functional MRI: [1] Movement execution task: subjects were instructed to pronate/supinate the arm in response to a visual cue. [2] Movement execution+imagery task: subjects were instructed to pronate/supinate the arm in response to the visual cue, but in addition were told to imagine that these movements were being performed to open and close a doorknob. fMRI analyses used SPM8 with threshold p RESULTS: For each condition, significant activation was present within the expected motor network, including left sensorimotor cortex and right cerebellum. Activation was significantly greater during performance of the movement execution+imagery task, compared to the movement execution task, within the left inferior parietal lobule and the right dorsolateral prefrontal cortex. No brain region showed greater activation during the movement execution task compared with the movement execution+imagery task. CONCLUSIONS: The movement execution+imagery task preferentially activated inferior parietal lobule and dorsolateral prefrontal cortex, regions that support goal-directed, complex movements. The addition of motor imagery to movement may provide a practical, accessible way to modulate activity in both the planning and the execution components of the motor network, and thereby further promote motor recovery after stroke.
Valuing Mortality-Risk Reduction: Using Visual Aids to Improve the Validity of Contingent Valuation

We investigate the validity of contingent valuation (CV) estimates of the value per statistical life (VSL). We test for sensitivity of estimated willingness to pay (WTP) to the magnitude of mortality-risk reduction and for the theoretically predicted proportionality of WTP to risk reduction using alternative visual aids to communicate risk. We find that WTP is sensitive to the magnitude of risk reduction for independent subsamples of respondents presented with each of three alternative visual aids, but not for the subsample presented with no visual aid. Estimated WTP is consistent with proportionality to risk reduction for the subsamples presented with a logarithmic scale or an array of 25,000 dots, but not for the subsample receiving a linear scale. These results suggest that CV can provide valid estimates of WTP for mortality-risk reduction if appropriate methods are used to communicate the risk change to respondents.
Effect of acute viral hepatitis in man on the disposition and elimination of meperidine.

The disposition and elimination of meperidine (Demerol) were compared in drug and alcohol-free, age-matched groups of 15 normal volunteers and 14 patients with acute viral hepatitis, while controlling the urinary pH at 7.0 or greater. In the controls, the plasma half-life (t1/2(β)) for meperidine was 3.37 ± 0.82 hr (mean ± SD), while in hepatitis patients it was significantly prolonged to 6.99 ± 2.74 hr (P
Image halftoning using optimized dot diffusion

The dot diffusion method for digital halftoning has the advantage of parallelism unlike the error diffusion method. However, image quality offered by error diffusion is still regarded as superior to other known methods. In this paper we show how the dot diffusion method can be improved by optimization of the so-called class matrix. By taking the human visual characteristics into account we show that such optimization consistently results in images comparable to error diffusion, without sacrificing the parallelism.
The Cost of the Game: A Taxonomy of Social Interactions

This paper considers the role of reciprocity rules in various strategic settings. After distinguishing four typical categories of social interaction, the paper examines three forms of reciprocity constraints. An ideal rule of perfect incentive alignment (“structural reciprocity”) serves as a benchmark for the analysis of a “golden rule” of reciprocity, characterized by a mechanical linking of one player's strategy to that of the other player; and a “silver rule” of stochastic reciprocity, characterized by a probabilistic symmetry in the relationship between the players.
ENTRAPMENT AS AN UNINTENDED CONSEQUENCE OF ENTREPRENEURIAL SUCCESS

One unintended consequence of entrepreneurial success may be that the entrepreneur becomes intertwined with the business. This phenomenon is called entrapment and we draw on Becker’s Side-Bet Theory to develop a series of hypotheses based on entrepreneurial success and individual difference variables. We surveyed 122 active entrepreneurs and found several significant relationships. To better understand these relationships, we conducted a second study using qualitative interviews with six entrepreneurs. Interview data suggested that entrepreneurs do indeed make side-bet type commitments, but increased financial success allows for the honoring of those commitments. The ability to honor commitments appears to leave the entrepreneur with a greater sense of alternatives and thereby reduces feelings of entrapment.
Teaching Physiology to Homeschool Students in Rural Mississippi

Purpose: To engage children in grades K-12 in interactive demonstrations and activities to learn about the structure and function of the heart, lungs, and digestive system. Methods: The event was coordinated with the Laurel Christian Home Educators at the Southeastern Baptist College in Laurel, MS. Five didactic and interactive sections were developed. In the first section, instructors introduced students to the daily routine of a scientist, including an appropriate safety protocol. In the second activity, participants were introduced to the basics of cardiovascular physiology, followed by an experiment measuring heart rate under various conditions. The third section focused on respiratory physiology, with a hands-on activity to measure lung capacity. Participants learned about the digestive system in the fourth section, and also had an activity to walk them through the entire digestive process. For the final station, participants were able to explore various organ models and fixed tissue samples of the s...
Transformations between Cryptographic Protocols

A transformation F between protocols associates the messages sent and received by participants in a protocol ${\it\Pi}_1$ with messages sent and received in some ${\it\Pi}_2$. Transformations are useful for modeling protocol design, protocol composition, and the services that protocols provide. A protocol transformation determines a map from partial behaviors ${\mathbb A}_1$ of ${\it\Pi}_1$--which we call "skeletons"--to skeletons $F({\mathbb A}_1)$ of ${\it\Pi}_2$. Good transformations should act as functors, preserving homomorphisms (information-preserving maps) from one ${\it\Pi}_1$-skeleton to another. Thus, if $H:{\mathbb A}_1\mapsto{\mathbb A}_2$ is a homomorphism between ${\it\Pi}_1$-skeletons, then there should be a homomorphism $F(H): F({\mathbb A}_1)\mapsto F({\mathbb A}_2)$ between their images in ${\it\Pi}_2$. We illustrate protocol transformation by examples, and show that our definition ensures that transformations act as functors.
Long-Term Yield Trends in the Rice-Wheat Cropping System: Results from Experiments and Northwest India

Summary Recent reports have questioned the long-term sustain-ability of the rice-wheat cropping system. Evaluation of yield trends in fifteen long-term rice-wheat experiments found that rice yields usually declined with time but that wheat yields were more stable. Nutrient response curves indicated that insufficient N was added to achieve maximum yield in some experiments, suggesting that crop lodging prevent genetic yield potential from being reached. Substantial decreases in response of rice to N were observed in some experiments, indicating constraints to productivity other than N supply. Organic inputs used in integrated nutrient management strategies generally substituted for fertilizer nutrients but occasionally increased yield potential. Neither organic inputs nor increased soil organic matter contents markedly affected the sustainability of the rice-wheat system. Wheat yields in the northwest Indian States of Haryana and Punjab increased linearly between 1965 and 1998 and are the major reason for ...
Consecutive radical S-adenosylmethionine methylations form the ethyl side chain in thienamycin biosynthesis.

Despite their broad anti-infective utility, the biosynthesis of the paradigm carbapenem antibiotic, thienamycin, remains largely unknown. Apart from the first two steps shared with a simple carbapenem, the pathway sharply diverges to the more structurally complex members of this class of β-lactam antibiotics, such as thienamycin. Existing evidence points to three putative cobalamin-dependent radical S-adenosylmethionine (RS) enzymes, ThnK, ThnL, and ThnP, as potentially being responsible for assembly of the ethyl side chain at C6, bridgehead epimerization at C5, installation of the C2-thioether side chain, and C2/3 desaturation. The C2 substituent has been demonstrated to be derived by stepwise truncation of CoA, but the timing of these events with respect to C2–S bond formation is not known. We show that ThnK of the three apparent cobalamin-dependent RS enzymes performs sequential methylations to build out the C6-ethyl side chain in a stereocontrolled manner. This enzymatic reaction was found to produce expected RS methylase coproducts S-adenosylhomocysteine and 5′-deoxyadenosine, and to require cobalamin. For double methylation to occur, the carbapenam substrate must bear a CoA-derived C2-thioether side chain, implying the activity of a previous sulfur insertion by an as-yet unidentified enzyme. These insights allow refinement of the central steps in complex carbapenem biosynthesis.
Optimization of individual well adaptive body biasing (IWABB) using a multiple objective evolutionary algorithm

Mitigating the effects process variations on power-frequency distributions can be done by using a system of locally-generated body biases. This system allows for highly localized circuit optimizations with very little overhead in silicon area and routing resources. We present a multiple objective algorithm to find near-optimal configurations of these biases which can be applied during post-fabrication testing. The system can improve an initial yield of 12% to 77%.
Lack of evidence for a role of Cys-138 as a base catalyst in the skeletal muscle 6-phosphofructo-2-kinase reaction

The role of Cys-138 in the catalysis of the skeletal muscle 6-phosphofructo-2-kinase reaction was investigated by mutating this residue to serine, glutamine and alanine, expressing the mutants in E. coli with a T7 RNA polymerase-based expression system, and analyzing their kinetic properties. The Cys138Ala mutant had greatly diminished activity, while the Cys138Ser and Cys138Gln mutants had maximal velocities 2-3 fold higher than the wild-type enzyme. It was concluded that Cys-138 does not act as a base catalyst in the kinase reaction, but that it plays a significant structural role in the enzyme's active site.
Rasch calibration of a unidimensional perfectionism inventory for sport.

Abstract Objective The purposes of this study were to generate and calibrate a unidimensional sports perfectionism scale for competitive athletes using the Rasch model, and validate the scale through the convergent and known-difference validity approach. Method The instrument, called the Sport Perfectionism Scale ( SPS ), was administered to 323 undergraduate students at a university in the southeastern U.S., ranging in age from 17 to 44 yrs, who previously competed on their high school team or currently compete at the intercollegiate level. Results Using the Rasch model, the level of item difficulty (i.e., most and least difficult) and the athlete's level (i.e., intensity) of perfectionism were estimated. Model-data fit was determined by Infit and Outfit statistics (≥0.5 and ≤1.5). With the exception of one item, the model fits the data well. Rasch analysis supported the measure of perfectionism in sport as a unidimensional construct. Data from the SPS were positively related with those from Stoeber, Otto, Pescheck, Becker, and Stoll's ([2007]. Perfectionism and competitive anxiety in athletes: differentiating striving for perfection and negative reactions to imperfection. Personality and Individual Differences, 42 , 959–969.) Perfectionism During Competitions measure ( r = 0.63), and there was a significant difference in athlete's perfectionism between levels of competition, F (3, 314) = 5.21, p = 0.002, partial eta-squared, 0.05. This result supports convergent and known-difference evidence of validity for the SPS. Conclusions These results lend credence to using the Rasch model as a unique approach to validate evidence of perfectionism as a unidimensional construct in competitive sport.
Perception of Animals and Cardiovascular Responses During Verbalization With an Animal Present

AbstractThe presence of animals has been associated with decreased physiological responses to stressors. Not all individuals respond equally to the presence of friendly animals. The current study was designed to examine whether attitudes toward animals are related to individuals' physiological responses when an animal is present. The relationship of individuals' perceptions of animals to their blood pressure and heart rate responses during verbalization in the presence of a dog were examined among urban college students (n=218). Lockwood's projective Animal Thematic Apperception Test (ATAT) was used to assess subjects' attitudes toward animals and people in scenes containing animals and identical scenes without animals. The significant period by perception interactions in analyses of variance with repeated measures revealed that cardiovascular responses to verbalization with an animal present were significantly lower for individuals who perceived scenes with animals more positively than for individuals wh...
Evidence for genetic recombination between endogenous and exogenous mouse RNA type C viruses

Abstract Two viruses isolated following prolonged growth of serologically distinct mouse type C RNA viruses in human cells have previously been shown to have acquired common envelope properties distinct from those of either parental virus. Virus neutralization tests show that the viruses selected in human cells possess envelope antigens identical to those of endogenous mouse type C viruses of cells in which the parental viruses had been propagated. In contrast, the p12 polypeptide of each virus selected in human cells is antigenically indistinguishable from that of its respective parental virus and different from those of known endogenous mouse type C viruses. Molecular hybridization indicates significant differences in the genetic sequences of one virus and its parent, excluding the possibility that it arose from a point mutation. These findings indicate that the viruses selected in human cells represent genetic recombinants between exogenous and endogenous mouse type C viruses.
Power-performance simulation: design and validation strategies

Microprocessor research and development increasingly relies on detailed simulations to make design choices. As such, the structure, speed, and accuracy of microarchitectural simulators is of critical importance to the field. This paper describes our experiences in building two simulators, using related but distinct approaches.One of the most important attributes of a simulator is its ability to accurately convey design trends as different aspects of the microarchitecture are varied. In this work, we break down accuracy---a broad term--- into two sub-types: relative and absolute accuracy. We then discuss typical abstraction errors in power-performance simulators and show when they do (or do not) affect the design rule choices a user of those simulator might make. By performing this validation study using the Wattch and Power Timer simulators, the work addresses validation issues both broadly and in the specific case of a fairly widely-used simulator.
Isolation and characterization of an hydroxykynureninase from homogenates of adult mouse liver

Abstract A kynureninase-type enzyme was isolated from adult mouse liver. With kynurenine as the substrate, this enzyme has a Km of 300 μ M ; when the substrate is hydroxykynurenine, the Km is 6 μ M . We conclude that this enzyme is an hydroxykynureninase. No enzyme which we could characterize as a kynureninase was found in this preparation. This suggests that tryptophan metabolism in the mouse occurs primarily through pathways that use hydroxykynurenine rather than kynurenine. Preliminary studies indicate that the enzyme is inhibited by its reaction product, hydroxyanthranilate, which is an intermediate in the synthesis of NAD. Such control of the hydroxykynureninase reaction may be of physiological importance in regulating the synthesis of NAD and/or in preventing the accumulation of hydroxyanthranilate, a putative carcinogen.
Further biochemical data on Qa-2

The Qa-2 differentiation alloantigen is coded by a gene situated between the D and Tla loci of the murine major histocompatibility complex (H-2). Qa-2-bearing protein was isolated by immunoprecipitation and found to be composed of subunits of 40 000 and 12 000 daltons by SDS polyacrylamide gel electrophoresis (PAGE). The 12 000 dalton material was identified as β2-microglobulin (β2M) by its molecular weight (SDS PAGE), charge (isoelectric focusing), antigenicity (reactivity with xenogenic anti-β 2M), and genetics. The 40 000 dalton mol. wt. of Qa-2 heavy chain is 5 000 daltons less than that of D and K molecules (45 000 daltons). The quantity of Qa-2 isolated by immunoprecipitation was found to vary in a strain-specific fashion and as much as a 15-fold difference was observed.
Music and the nucleus accumbens

Music is a universal feature of human societies over time, mainly because it allows expression and regulation of strong emotions, thus influencing moods and evoking pleasure. The nucleus accumbens (NA), the most important pleasure center of the human brain (dominates the reward system), is the ‘king of neurosciences’ and dopamine (DA) can be rightfully considered as its ‘crown’ due to the fundamental role that this neurotransmitter plays in the brain’s reward system. Purpose of this article was to review the existing literature regarding the relation between music and the NA. Studies have shown that reward value for music can be coded by activity levels in the NA, whose functional connectivity with auditory and frontal areas increases as a function of increasing musical reward. Listening to music strongly modulates activity in a network of mesolimbic structures involved in reward processing including the NA. The functional connectivity between brain regions mediating reward, autonomic and cognitive processing provides insight into understanding why listening to music is one of the most rewarding and pleasurable human experiences. Musical stimuli can significantly increase extracellular DA levels in the NA. NA DA and serotonin were found significantly higher in animals exposed to music. Finally, passive listening to unfamiliar although liked music showed activations in the NA.
Polymers derived from fluoroketones. II. Wetting properties of fluoroalkyl acrylates and methacrylates

The critical surface tension of wetting (γc) for certain branched-chain polymeric fluoroalkyl acrylates and methacrylates was obtained. Polymeric materials utilized in this study can be represented by the repeating units , where R is H or CH3, R′ is H or F, and X is F or Cl, by , where n is 2, 5, or 11, and by , where R is H or CH3 and n′ is 2 or 6. Monomer synthesis involved either the direct acylation of a fluoroketone–metal fluoride adduct or a fluoroalcohol with acryloyl or methacryloyl chloride or a displacement reaction between a fluoroketone–metal fluoride adduct and an ω-bromoester. In general, modifications in the pendent fluoroalkyl group affected γc in a manner predictable from previous work by Zisman et al.; e.g., γc was increased when either H or Cl was substituted for F in the side chain. In polymeric alkyl acrylates containing a heptafluoroisopropyl side chain γc increased as the fluorocarbon group was removed from the proximity of the polymer backbone by intervening methylene groups. A comparison of the wetting properties of polyacrylates containing either a perfluoroisopropyl or n-perfluoropropyl group showed that the polymer containing the isopropyl group had a lower γc.
Dissociative extraction and partial purification of osteogenin, a bone inductive protein, from rat tooth matrix by heparin affinity chromatography.

Summary Implantation of demineralized tooth matrix in subcutaneous sites results in new bone formation locally. The osteoinductive activity of the tooth matrix was dissociatively extracted in 4.0 M guanidine hydrochloride and the residue was devoid of biologic activity. The bone inductive protein, osteogenin, was partially purified by heparin affinity chromatography. The heparin binding fraction initiated the bone differentiation cascade when implanted with guanidine extracted, inactive bone or tooth matrices. These results imply a cooperative interaction between the soluble osteogenin and collagenous substratum in bone induction.
A hybrid finite element method for stokes flow: Part II—Stability and convergence studies

Abstract In Part I we have presented a hybrid finite element method based on an assumed stress field which has the features: (i) the unknowns in the final system of finite element equations are (a) the nodal velocities, and (b) the ‘constant term’ in the arbitrary pressure field over each element; (ii) ‘exact’ integrations were performed for each element. In the following we present studies of stability and convergence of the above hybrid finite element method.
Stoichiometry and local atomic arrangements in crystals

Abstract Valence crystals have bulk stoichiometries that are electroneutral with respect to formal atomic valence, and structures in which cation sites are formed entirely by anions and vice versa. This description is shown to be equivalent to a set of stoichiometric and structural rules limiting local atomic configurations in valence crystals. Algebraic equivalents of these rules are used to derive a necessary mathematical link between bulk stoichiometry and local atomic arrangements in valence crystals. In the limit of no charge imbalances on anion sites, this link reduces to the electrostatic valence principle of Pauling. Numerical analysis shows that limits upon the coordination numbers of cations and anions severely restrict the number and type of local configurations that could ever be combined to form an electroneutral bulk stoichiometry, regardless of the valence of the anion or the magnitude of charge imbalances on anion sites.
Ecology of SO2 resistance: II. Photosynthetic changes of shrubs in relation to SO2 absorption and stomatal behavior.

In an effort to predict SO2 sensitivity of plants from their morphological and physiological features, the effects of SO2 on photosynthesis were partitioned between stomatal and nonstomatal components for a drought deciduous shrub, Diplacus aurantiacus, and an evergreen shrub, Heteromeles arbutifolia. As predicted, the drought deciduous shrub had the higher gas conductance, and hence SO2 absorptance. However, nonstomatal components also play a role in determining SO2 sensitivity. Apparently a plant with a high intrinsic photosynthetic capacity will be more sensitive to SO2 than one with a lower capacity.
A method for staining virus particles and identifying their nucleic acid type in the electron microscope.

Abstract A method is described for staining virus particles from fluid suspensions with uranyl acetate and phosphotungstic acid so as to enhance contrast for electron microscopy and yet maintain good structural detail. The method requires 100–1000 times less virus concentration than the spray droplet technique. Staining can be substituted for metal shadowing in the agar pseudoreplication technique and can be used for counting virus particles. Treatment with uranyl acetate reduces structural distortion of herpes virus particles on drying. Substantial differences have been noted between the appearance of RNA- and DNA-containing animal viruses after staining. Under the same conditions the cores of DNA-type viruses stain intensely with uranyl acetate, whereas the RNA-type viruses do not. The combined use of specific nuclease, negative staining (phosphotungstate), and positive staining (uranyl acetate) is suggested as a means of differentiating RNA from DNA viruses by microscopy.
The C13H satellite NMR spectra of the vinyl halides

Abstract C13H satellite NMR spectra have been observed and analyzed for all four vinyl halides using a least-squares procedure that involves simultaneous fitting of all satellite patterns and the normal spectrum for each halide. All short-range C13H couplings have been determined, in addition to a limited amount of data concerning long-range C13H coupling and a complete set of proton shifts and couplings at infinite dilution. The effect of CX bond diamagnetic anisotropy has been considered and the C13H coupling constants have been discussed briefly.
On upscaling operator-stable Lévy motions in fractal porous media

The dynamics of motile particles, such as microbes, in random porous media are modeled with a hierarchical set of stochastic differential equations which correspond to micro, meso and macro scales. On the microscale the motile particle is modeled as an operator stable Levy process with stationary, ergodic, Markov drift. The micro to meso and meso to macro scale homogenization is handled with generalized central limit theorems. On the mesoscale the Lagrangian drift (or the Lagrangian acceleration) is assumed Levy to account for the fractal character of many natural porous systems. Diffusion on the mesoscale is a result of the microscale asymptotics while diffusion on the macroscale results from the mesoscale asymptotics. Renormalized Fokker-Planck equations with time dependent dispersion tensors and fractional derivatives are presented at the macro scale.
PROPHYLACTIC INDOMETHACIN AND INTRAVENTRICULAR HEMORRHAGE (IVH) IN THE PREMATURE

We have previously shown significant hemostatic derangements associated with IVH and have questioned the use of indomethacin [I] , a potent platelet anti-aggregating agent in infants vulnerable to IVH. During a prospective study of [I] prophylaxis for patent ductus arteriosus (PDA), we assessed the impact of [I] upon the incidence of IVH. Sixty one inborn infants were randomized by birth weight (Group A: <900 gm; Group B: 900-1300 gm) to receive either placebo [P] or [I] . The first dose (0.2 mg/kg), given within 12 hours after birth, was followed by two q 12 hourly doses (0.1 mg/kg). Cranial ultrasonography was performed prior to dose # 1, daily for 3 days and at 1 week. Abnormal scans were repeated weekly. The most severe grade of IVH (Papile criteria) sustained by each infant is shown below: In Group A, 2 of 10 (20%) of infants who received I developed IVH (Grades II-IV) in contrast to 8 of 10 (80%) of infants given [P], p < 0.025. In Group B, there was no significant difference in IVH between [I] and [P] These preliminary data suggest that prophylactic [I] may diminish the incidence of IVH in infants < 900 grams, perhaps by preventing clinically significant PDA or by altering prostaglandin-related central nervous system vascular phenomena.
Parsons on Stratification: An Analysis and Critique

(1965). Parsons on Stratification: An Analysis and Critique. The Sociological Quarterly: Vol. 6, No. 2, pp. 128-138.
Histological evidence for hair cell regeneration after ototoxic cell destruction with local application of gentamicin in the chinchilla crista ampullaris

Abstract Two experiments were conducted to study the ototoxic effects of local gentamicin (GM) administration and the subsequent hair cell (HC) regeneration process in the chinchilla cristae ampullares (CA). In the first experiment, 3 different doses of GM (0.1, 0.2 and 1.2 mg) were administered by surgical implantation of GM-soaked Gelfoam® pledgets in the perilymphatic space in the otic capsule of the left superior semicircular canal. The CA was histologically processed for light-microscopic examination. In the second experiment, 6 groups of 2 chinchillas each were treated with 0.1 mg of GM. To document cell proliferation and HC regeneration, Alzet® micro-osmotic pumps were implanted in each chinchilla to deliver bromodeoxyuridine (BrdU) at 125 μg/h for 1 week. Chinchillas were subsequently killed at 1 and 4 days and 1, 2, 4 and 8 weeks post-treatment (PT). The CA was processed for light microscopy and BrdU immunocytochemistry. In the first experiment the smallest dose produced damage restricted to HCs alone, while the medium and large doses produced severe damage in the sensory epithelium, including supporting cells and HCs. Results in the second experiment demonstrated that at 1 and 4 days PT and HCs showed extensive damage, including clumping of nuclear material. By 4 days PT the supporting cell nuclei lost their monolayer configuration. Calyceal terminals appeared empty, and vacuolized remnants of nerve calyces were evident in the basal portion. At 1 week PT complete disappearance of HCs from the sensory epithelium was evident, and there was cytoplasmic extrusion into the endolymphatic space. At 2 weeks PT there was complete HC loss, the supporting cell nuclei were scattered randomly in the crista, and the nerve fibers were retracted from the sensory epithelium. At 4 weeks PT there was evidence of sensory epithelium repair and HC regeneration. Short cells resembling type-II HCs were evident in the surface of the sensory epithelium. At 8 weeks PT the number of HCs increased in a uniform fashion on the surface of the sensory epithelium, and the supporting cell nuclei were realigned on the basal membrane. Nerve fibers with growth cones penetrated the basal membrane. Supporting cell proliferation was evident by the presence of mitotic figures and BrdU immunoreactivity in the chromatin material of dividing cells at 2 weeks PT. The labeling was more evident in newly formed cells at 4 and 8 weeks PT. These results demonstrate that in chinchillas the vestibular organs have the capacity of self-repair and the process includes HC regeneration after local administration of GM. The overall process involves changes in different cells in the sensory epithelium and neural elements, all of which show modifications with an orderly pattern.
Data errors in emt licensure evaluator article

(1999). Data errors in emt licensure evaluator article. Prehospital Emergency Care: Vol. 3, No. 2, pp. 175-178.
Interaction of insulin-like growth factor-II and estradiol directs steroidogenesis in the human fetal adrenal toward dehydroepiandrosterone sulfate production.

We examined the regulation of steroid production in fetal zone cells from midgestation (16-21 weeks) human fetal adrenal glands to elucidate the mechanism by which these cells secrete large quantities of dehydroepiandrosterone sulfate (DHAS) and little cortisol in response to ACTH. Our underlying hypothesis is that estrogen and insulin-like to ACTH. Our underlying hypothesis is that estrogen and insulin-like growth factor-II (IGF-II) modulate the steroidogenic response of fetal zone cells to ACTH, driving steroid production toward DHAS rather than cortisol. We also hypothesize that the effects of IGF-II and estrogen on steroidogenesis are achieved by modulating the expression of key enzymes in the steroidogenic pathway. Basal cortisol secretion by cultured fetal zone cells was below the limit of assay sensitivity (< 0.54 pmol/10(5) cells.24 h), whereas basal DHAS secretion was 210.8 +/- 41.0 pmol/10(5) cells.24 h (mean +/- SE). ACTH-(1-24) increased the secretion of cortisol to 228.96 +/- 6.75 pmol/10(5) ...
Growth and oxidation resistance of boron-modified and germanium-doped silicide diffusion coatings formed by the halide-activated pack cementation method

Abstract Niobium-base and titanium-base alloys and intermetallic compounds possess many attractive properties, but practical application at high temperature is limited by their rapid scaling and embrittlement by oxygen dissolution. Since alloying schemes have not provided an acceptable balance of oxidation resistance and mechanical properties, protective coatings are required. Procedures for codepositing either silicon and boron, or else silicon and germanium, in a single reaction-processing step by a fluoride-activated, pack cementation method have been developed. These B-modified and Ge-doped silicide coatings were grown on commercially pure titanium, Ti−20A1−22Nb, Ti−22Al−27Nb and Nb−40Ti−15A1 alloys by direct conversion of the base metal into a TiSi 2 -base coating. For Nb-base alloys, a protective Ge-doped MoSi 2 coating was grown by the diffusive conversion of a Mo layer deposited by physical vapor deposition. These diffusion coatings have been characterized, and their performance was evaluated by cyclic oxidation in air. Microhardness profiles were used to demonstrate the absence of oxygen contamination for the coated substrates. Preliminary fatigue testing of coated substrates is reported.
A homogeneity condition guaranteeing bifurcation in multiparameter nonlinear eigenvalue problems

On montre qu'un point de bifurcation de multiplicite impaire n'est jamais isole dans l'ensemble des points de bifurcation. On introduit une notion de variete de codimension 1 et on utilise ce concept et une theorie de perturbation pour decrire completement l'ensemble des points de bifurcation proches d'un point de multiplicite un sous l'hypothese que l'application λ→A(λ) est continue
Importance of acquired systemic-to-pulmonary collaterals in the Fontan operation

Abstract Background . Children with chronic cyanotic heart disease often develop systemic-to-pulmonary collateral arteries that can be deleterious at the time of a Fontan procedure due to excessive pulmonary blood flow. We therefore occlude all significant collaterals during cardiac catheterization. Methods . From June 1993 to May 1998, 93 children aged 1.5 to 15.8 years (median 2.5 years) underwent a fenestrated lateral tunnel Fontan procedure. Eighty-nine (96%) had a previous bidirectional Glenn anastomosis, including 31 (33%) with a Norwood procedure. Results . Preoperatively, 33 children (35%) required occlusion of 1 to 11 (mean 3.6) collateral vessels. Two of the three perioperative deaths (operative survival 97%) were due to excessive pulmonary blood flow from unrecognized collaterals in one and uncontrollable collaterals in the other. Postoperatively, 19 children (20%) required coil occlusion of 1 to 21 (mean 5.6) collaterals for elevated pulmonary artery pressures, heart failure, or prolonged chest tube drainage. Duration of inotropic support, postoperative ventilation, intensive care unit stay, and postoperative hospitalization were all significantly longer in the patients who had postoperative occlusion of collaterals. On follow-up of 2 to 67 months (mean 35 months), there have been four late deaths (two infections, two heart failures); 6 patients underwent successful cardiac transplantation for refractory heart failure. All 8 patients with ventricular failure required occlusion of significant collaterals postoperatively. Conclusions . Hemodynamically significant collaterals are not uncommon in Fontan candidates, and aggressive control can result in good operative and medium-term survival. After the Fontan, significant collaterals may be a marker for eventual cardiac failure because 8 of 18 patients requiring postoperative coils went on to transplantation or died of heart failure.
Comparison of Cemented and Cementless Total Hip Arthroplasty in Patients With Bilateral Hip Arthroplasties

A consecutive series of 36 patients underwent primary cemented total hip arthroplasty followed by primary cementless total hip arthroplasty of the contralateral hip. Clinical pain scores between the cementless and cemented hips were not different. Subjectively, patients either had no preference or preferred the cementless side. Comparison of results in the same patient eliminates variability introduced by differences in sex, weight, comorbidities, bone quality, and activity level. Control of these factors permits more meaningful comparison of the type of fixation.
Economic Theories of Disability Benefits

Within government social welfare policies and programs, disability has frequently been defined and addressed as an economic issue, linked to the ability (or inability) to work. This article comprises a brief review of literature concerned with economic theories related to disability, with a primary focus on public disability benefits. The explanatory theories of rational choice, supply and demand, and moral hazard are discussed in the context of disability benefits and the normative fields of welfare economics and social choice theory as they relate to disability. Finally, implications of the economic perspective for the analysis of human behavior and the social environment are identified.
Allometry and model II non-linear regression

Abstract For many allometry problems, morphological variables, x and y, can be transformed using logarithms and linear techniques used to estimate parameters and compare samples. Because both x and y are subject to errors, Model II regression has been advocated for such analyses. When data, such as gonad weight or egg number, are analyzed using a more complex allometry equation such as y = αxβ + γ or y = α(x - γ)β, non-linear regression techniques must be used. We present a Model II non-linear analog of reduced major-axis (RMA) regression that minimizes areas similar to triangles that are minimized in RMA regression. Data for two tropical sea urchins, Salmacis belli and Heterocentrotus mammillatus, illustrate the method.
A multi‐platform bathyphotometer for fine‐scale, coastal bioluminescence research

Although bioluminescence (BL) in the open ocean has been extensively studied, coastal BL remains poorly understood due, in large degree, to a lack of BL instrumentation appropriate to measure the fine-scale biological and physical complexity of the coastal regime. As a contribution toward understanding coastal BL, we developed the Multipurpose Bioluminescence Bathyphotometer (MBBP). This compact, self-contained bathyphotometer (BP) was designed to function in a variety of deployment modes, including conventional shipboard profilers, towed platforms, autonomous underwater vehicles (AUVs), and profiling moorings. In all configurations, the instrument preserves signal structure at centimeter to meter scale resolution, the scale at which higher-flow instruments might disturb thin layers and other fine-scale water column features. In the MBBP, seawater is conveyed with minimal premeasurement excitation into a light-baffled stimulation and measurement chamber at a continuously measured flow rate of 350 to 400 mL s−1. A photomultiplier tube (PMT) records light from bioluminescent organisms after they are mechanically stimulated at the chamber entrance by a high-velocity impeller. Calibration and test protocols were developed to determine BL stimulation efficiency and MBBP measurement characteristics. To illustrate the capabilities of the MBBP to resolve the fine-scale structure of the BL community, measurements from two coastal environments are presented.
Animals as an Energy Source in Third World Agriculture

Agricultural development programs have so far been largely unable to meet the food needs of the world's poorest. Increased food production can be achieved only from more intensive agriculture, which requires greater energy inputs per farm worker. Problems of technological infrastructure and escalating oil prices appear to preclude the spread of mechanization to Third World agriculture at this time. Efficient utilization of grazing animals in specific integrated farming systems could not only increase energy inputs through draft and transportation but also increase the yield of high-grade products and by-products from the renewable energy of biomass. An approach to development based on animal agriculture systems is suggested that might initiate a self-sustaining, more productive agriculture requiring only small inputs of fossil-fuel energy.
Robust Kalman filters for linear time-varying systems with stochastic parametric uncertainties

We present a robust recursive Kalman filtering algorithm that addresses estimation problems that arise in linear time-varying systems with stochastic parametric uncertainties. The filter has a one-step predictor-corrector structure and minimizes an upper bound of the mean square estimation error at each step, with the minimization reduced to a convex optimization problem based on linear matrix inequalities. The algorithm is shown to converge when the system is mean square stable and the state space matrices are time invariant. A numerical example consisting of equalizer design for a communication channel demonstrates that our algorithm offers considerable improvement in performance when compared with conventional Kalman filtering techniques.
Diffuse Optical Detection of Cerebral Ischemia During Carotid Endarterectomy

Cerebral blood flow and oxygenation were monitored by diffuse optical spectroscopes during carotid endarterectomy (CEA). The results demonstrate high sensitivity of diffuse optical spectroscopes in detecting cerebral ischemia due to arterial clamping during CEA.
Drug Dosage Adjustment Using Renal Estimation Equations: A Review of the Literature:

PurposeTo examine the factors affecting drug clearance and the available evidence for drug dosing based on the Cockcroft-Gault (CG) equation and the abbreviated Modification of Diet in Renal Diseas...
Synthesis of specific transfer ribonucleic acids during methionine starvation in Escherichia coli 113-3

Abstract Escherichia coli mutant 113-3, derived from strain W, requires either vitamin B12 or methionine for growth. Ribonucleic acids are synthesized without concomitant protein synthesis and cell multiplication when a culture of this mutant is incubated in the absence of methionine. The amounts of RNA and transfer RNA synthesized during methionine starvation depended on the duration of incubation. The co-ordination ratio of tRNA to total RNA indicated that synthesis of tRNA is regulated non-co-ordinately with reference to total RNA during methionine starvation. It is proposed that all classes of RNA are regulated non-co-ordinately in the absence of methionine in this strain. Reverse-phase chromatography revealed two peaks for valyl-tRNA under normal conditions, while under conditions of methionine deprivation an additional peak was found. These observations indicate the synthesis of a new species of undermethylated tRNA which is charged by valyl-tRNA synthetase. The possibility is discussed that this new undermethylated sub-species of valyl-tRNA synthesized in the absence of methionine is a “pre-tRNA”.
Saturable reactors with inductive D-C load: Part II. Transient response

ALINEAR inductive reactor can be symbolically represented in several different ways. The first and most common presentation is shown in Figure 1, where L is a pure inductance and R a pure resistance. The current 1 as a function of the applied step voltage E is in operational form1 $I = {E \over R+PL} \eqno{\hbox{(1)}}$
S103L reactive chondroitin sulfate proteoglycan (aggrecan) mRNA expressed in developing chick brain and cartilage is encoded by a single gene

A large chondroitin sulfate proteoglycan (CSPG) identified in embryonic chick brain, and synthesized exclusively by neurons in a developmentally expressed pattern that coincides with migration and establishment of neuronal nuclei, reacts with a monoclonal antibody (S103L) developed against the cartilage-specific CSPG, aggrecan. The relationship of the brain and cartilage S103L CSPGs was established by chemical, biosynthetic and molecular analyses. Significant posttranslational differences (absence of keratan sulfate (KS), less CS, and different sulfation patterns) distinguish the brain S103L species from the cartilage S103L species. However, quantitative and qualitative Northern analysis, cassette RT-PCR and direct cloning and sequencing of the entire brain-specific S103L CSPG coding sequence, all indicate that the brain and cartilage core proteins are identical. Thus, although the S103L CSPG synthesized by chick brain and cartilage are the product of a single gene, they are clearly biochemically distinct and differentially expressed proteoglycan products, suggesting tissue specific roles for these proteoglycan homologs.