cssi/SciSciGPT-SciSciNet huggingface dataset:
Trends and subgroup differences in transportation-related injury risk and safety behaviors among high school students, 1991-1997

Abstract Purpose: To examine national trends in transportation-related injury risk and safety behaviors among U.S. high school students. Methods: To examine secular trends in riding with a driver who had been drinking, driving after drinking, and using seat belts, bicycle helmets, and motorcycle helmets, we used logistic regression to analyze data from national Youth Risk Behavior Surveys (YRBS) conducted in 1991, 1993, 1995, and 1997. The YRBS is a self-administered, anonymous survey that uses a national probability sample of U.S. students in public and private schools from grades 9–12 ( N = 55,734 for all years combined). Results: The percentages of students who rode with a driver who had been drinking (36.6% in 1997), drove after drinking alcohol (16.9% in 1997), always wore seat belts (33.2% in 1997), and always wore a motorcycle helmet when riding a motorcycle (45.0% in 1997) remained stable between 1991 and 1997. From 1991 to 1997, the percentage of bicycle riders who always wore a helmet when bicycling showed a small but statistically significant increase (1.1% in 1991 to 3.8% in 1997), but helmet use remained low. Conclusion: Many young people place themselves at unnecessary risk for motor vehicle– and bicycle-related crash injuries and fatalities. Improved motor vehicle– and bicycle-related injury prevention strategies are needed that specifically target adolescents.
Non-Hermitian Dynamics of Multiphoton Ionization

The time evolution of a multiphoton ionization process may be analyzed from a variety of viewpoints, the suitability of any particular one being determined in large measure by the relative time scales among various competing effects. In a process such as multiphoton ionization by intense coherent light, the ionizing state may well also retain coherence over practically the entire time of passage of the ionizing light pulse. In this situation, where the ionization is much more rapid than, for example, spontaneous emission of a photon, a hamiltonian formulation of the dynamics may be appropriate. As we shall indicate, such a formulation may facilitate certain aspects of the analysis. In addition, the non-hermitian hamiltonian formalism described here has intrinsic theoretical interest.
Research Anxiety and Students' Perceptions of Research: An Experiment. Part II. Content Analysis of Their Writings on Two Experiences.

This is Part II of an experimental study investigating students' perceptions of research and research paper anxiety. The study integrates quantitative and qualitative designs to collect complimentary data. The participants were students in four sections of an upper division undergraduate course on technical and professional writing during the fall of 1999. A survey instrument used the Critical Incident Technique to solicit writings in students' own words about a memorable past research and writing experience at the beginning of the semester and the current research and writing at the end of the semester. The quantitative part of the survey measured students' perceptions about research using a questionnaire with five-point Likert scale, and students' anxiety levels using a standard state anxiety test (STAI Y-1). The first article, Part I, provides a detailed description of the experimental design and reports on quantitative results. This article reports on content analysis of students' writings about their experiences of the two research projects. Analysis of the data confirmed Kuhlthau's Information Search Process (ISP) model and revealed additional affective and cognitive aspects related to research and writing.
Regulation of hsp70 mRNA levels during oocyte maturation and zygotic gene activation in the mouse

Abstract Protein phosphorylation catalyzed by the cAMP-dependent protein kinase is implicated in transcriptional activation of the embryonic genome in the two-cell mouse embryo, while heat shock protein (hsp70) has been identified as one of the first products of zygotic gene activation. Using reverse transcription-polymerase chain reaction we have analyzed relative changes in the amount of hsp70 mRNA during oocyte maturation and early embryogenesis. We report that the amount of hsp70 mRNA decreases after germinal vesicle breakdown, while inhibiting germinal vesicle breakdown inhibits this maturation-associated decrease. The amount of hsp70 mRNA increases between the one- and two-cell stages. This increase is inhibited by either α-amanitin or the cAMP-dependent protein kinase inhibitor H-8; the same concentration of H-7, which is a more potent inhibitor of protein kinase C, has little inhibitory effect on this increase in the relative amount of hsp70 mRNA. Last, addition of cycloheximide to one-cell embryos late in G2 inhibits neither cleavage to the two-cell stage nor the increase in the relative amount of hsp70 mRNA. These results strengthen the previous proposal that protein phosphorylation is involved in zygotic gene activation in the two-cell mouse embryo.
Single intra-articular injection of adeno-associated virus results in stable and controllable in vivo transgene expression in normal rat knees

Summary Objective To test the hypothesis that in vivo transgene expression mediated by single intra-articular injection of adeno-associated virus serotype 2 (AAV2) persists within intra-articular tissues 1 year post-injection and can be externally controlled using an AAV2-based tetracycline-inducible gene regulation system containing the tetracycline response element (TRE) promoter. Methods Sprague Dawley rats received intra-articular injections of AAV2-cytomegalovirus (CMV)-enhanced green fluorescent protein (GFP) and AAV2-CMV-luciferase (Luc) into their right and left knees, respectively. Luciferase expression was evaluated over 1 year using bioluminescence imaging. After sacrifice, tissues were analyzed for GFP+ cells by fluorescent microscopy. To study external control of intra-articular AAV-transgene expression, another set of rats was co-injected with AAV2-TRE-Luc and AAV2-CMV-reverse-tetracycline-controlled transactivator (rtTA) into the right knees, and AAV2-CMV-Luc and AAV2-CMV-rtTA into the left knees. Rats received oral doxycycline (Dox), an analog of tetracycline, for 7 days. Luciferase expression was assessed by bioluminescence imaging. Results Luciferase expression was localized to the injected joint and persisted throughout the 1-year study period. Abundant GFP+ cells were observed within intra-articular soft tissues. Transgene expression in AAV2-TRE-Luc injected joints was upregulated by oral administration of Dox, and downregulated following its removal, at 14 days and 13 months post-AAV injection. Conclusions This longitudinal in vivo study shows that sustained and stable AAV-mediated intra-articular transgene expression can be achieved through a single intra-articular injection and can be controlled using a tetracycline-controlled inducible AAV system in a normal rat knee model. Highly regulatable long-term intra-articular transgene expression is of potential clinical utility for development of treatment strategies for chronic intra-articular disease processes such as inflammatory and degenerative arthritis.
Measurement of HO2NO2 in the free troposphere during the Intercontinental Chemical Transport Experiment–North America 2004

[1] The first direct in situ measurements of HO2NO2 in the upper troposphere were performed from the NASA DC-8 during the Intercontinental Chemical Transport Experiment–North America 2004 with a chemical ionization mass spectrometer (CIMS). These measurements provide an independent diagnostic of HOx chemistry in the free troposphere and complement direct observations of HOx, because of the dual dependency of HO2NO2 on HOx and NOx. On average, the highest HO2NO2 mixing ratio of 76 pptv (median = 77 pptv, σ = 39 pptv) was observed at altitudes of 8–9 km. Simple steady state calculations of HO2NO2, constrained by measurements of HOx, NOx, and J values, are in good agreement (slope = 0.90, R2 = 0.60, and z = 5.5–7.5 km) with measurements in the midtroposphere where thermal decomposition is the major loss process. Above 8 km the calculated steady state HO2NO2 is in poor agreement with observed values (R2 = 0.20) and is typically larger by a factor of 2.4. Conversely, steady state calculations using model-derived HOx show reasonable agreement with the observed HO2NO2 in both the midtroposphere (slope = 0.96, intercept = 7.0, and R2 = 0.63) and upper troposphere (slope = 0.80, intercept = 32.2, and R2 = 0.58). These results indicate that observed HO2 and HO2NO2 are in poor agreement in the upper troposphere but that HO2NO2 levels are consistent with current photochemical theory.
Untying the Knot: Do Personal and Organizational Determinants Influence Entrepreneurial Intentions?

Abstract An integrated model of entrepreneurial intentions was proposed and empirically tested. This model investigated the role of personal and organizational factors that influence entrepreneurial intentions. The personal factor examined was an individual's proactive personality whereas the organizational factor included an individual's loyalty (commitment and obligation to remain with the organization) to his/her current employer. It was hypothesized that the interactive effects of both of these factors will affect entrepreneurial intentions. Hierarchical regression analysis found support for this interaction. The negative relationship between commitment and entrepreneurial intentions was sigificant only when proactive personality was high.
Aerosol retrievals from channel-1 and -2 AVHRR radiances: Long-term trends updated and revisited

Abstract The nominal Global Aerosol Climatology Project (GACP) record of aerosol optical thickness (AOT) and Angstrom exponent (AE) over the oceans is extended by 6 months to cover the period from August 1981 through December 2005. The most recent 4-year segment reveals no significant short-term tendencies in globally and hemispherically averaged AOTs and AEs. This finding is consistent with contemporaneous MODIS and MISR results and the accumulating evidence of a gradual transition from global brightening to global dimming. We also analyze the retrieval implications of allowing the imaginary part of the aerosols refractive index Im( m ) to change over the duration of the GACP record. Our sensitivity study shows that increasing Im( m ) from 0.003 during the 4-year pre-Pinatubo period up to 0.007 during the most recent 4-year segment of GACP data eliminates the previously identified long-term decreasing AOT trend. Should this long-term trend in Im( m ) be real then it would cause the global absorption AOT over the oceans to more than double and the global single-scattering albedo to decrease from ∼0.95 to ∼0.88. Such changes could make tropospheric aerosols significant contributors to the recent surface temperature increase.
Family and work predictors of parenting role stress among two‐earner families of children with disabilities

Family resources (i.e. household income and spouse support), parenting challenges (i.e. number of children, difficulty finding reliable child care, and child characteristics), work rewards (i.e. work interest) and work demands (i.e. hours and work overload) were tested as predictors of parenting role stress among mothers and fathers in two-earner families of five-year old children with disabilities. The two-level hierarchical model was adapted to assess mothers and fathers as nested within married couples. Both common and unique predictors of maternal and paternal parenting role stress were found. Having fewer children in the family predicted less stress for both parents. Household income and an interaction between child behaviour problems and work interest were significant predictors of maternal parenting role stress. In contrast, greater difficulty in finding reliable child care predicted higher levels of parenting role stress for fathers but not mothers. The policy and research implications of these findings are discussed. Copyright © 2005 John Wiley & Sons, Ltd.
PRENATAL PHTHALATE EXPOSURE AND PERFORMANCE ON THE NEONATAL BEHAVIORAL ASSESSMENT SCALE IN A MULTIETHNIC BIRTH COHORT

We investigated the relationship between prenatal maternal urinary concentrations of phthalate metabolites and neonatal behavior in their 295 children enrolled in a multiethnic birth cohort between 1998 and 2002 at the Mount Sinai School of Medicine in New York City. Trained examiners administered the Brazelton Neonatal Behavioral Assessment Scale (BNBAS) to children within 5 days of delivery. We measured metabolites of 7 phthalate esters in maternal urine that was collected between 25 and 40 weeks' gestation. All but two phthalate metabolites were over 95% detectable. We summed metabolites on a molar basis into low and high molecular weight phthalates. We hypothesized the existence of sex-specific effects from phthalate exposure a priori given the hormonal activity of these chemicals. Overall we found few associations between individual phthalate metabolites or their molar sums and most of the BNBAS domains. However, we observed significant sex-phthalate metabolite interactions (p<0.10) for the Orientation and Motor domains and the overall Quality of Alertness score. Among girls, there was a significant linear decline in adjusted mean Orientation score with increasing urinary concentrations of high molecular weight phthalate metabolites (B=-0.37, p=0.02). Likewise, there was a strong linear decline in their adjusted mean Quality of Alertness score (B=-0.48, p<0.01). In addition, boys and girls demonstrated opposite patterns of association between low and high molecular weight phthalate metabolite concentrations and motor performance, with some indication of improved motor performance with increasing concentration of low molecular weight phthalate metabolites among boys. This is the first study to report an association between prenatal phthalate exposure and neurological effects in humans or animals, and as such requires replication.
Fundamental limits and tradeoffs of providing deterministic guarantees to VBR video traffic

Compressed digital video is one of the most important traffic types in future integrated services networks. However, a network service that supports delay-sensitive video imposes many problems since compressed video sources are variable bit rate (VBR) with a high degree of burstiness. In this paper, we consider a network service that can provide deterministic guarantees on the minimum throughput and the maximum delay of VBR video traffic. A common belief is that due to the burstiness of VBR traffic, such a service will not be efficient and will necessarily result in low network utilization. We investigate the fundamental limits and tradeoffs in providing deterministic performance guarantees to video and use a set of 10 to 90 minute long MPEG-compressed video traces for evaluation. Contrary to conventional wisdom, we are able to show that, in many cases, a deterministic service can be provided to video traffic while maintaining a reasonable level of network utilization. We first consider an ideal network environment that employs the most accurate deterministic, time-invariant video traffic characterizations, Earliest-Deadline-First packet schedulers, and exact admission control conditions. The utilization achievable in this situation provides the fundamental limits of a deterministic service. We then investigate the utilization limits in a network environment that takes into account practical constraints, such as the need for fast policing mechanisms, simple packet scheduling algorithms, and efficient admission control tests.
Effects of local cholinesterase inhibition on acetylcholine release assessed simultaneously in prefrontal and frontoparietal cortex

To investigate whether acetylcholine is released in a similar fashion in different regions of the cortex, in vivo microdialysis was used to measure acetylcholine efflux simultaneously in the medial prefrontal and the frontoparietal cortex, under both basal conditions and following tactile stimulation. Additionally, the effects of including two different concentrations (0.05 microM and 0.5 microM) of a cholinesterase inhibitor (neostigmine) in the perfusion fluid were assessed. Basal levels of acetylcholine (i.e. during non-stimulated sessions) were similar in medial prefrontal and frontoparietal areas. Tactile stimulation reliably increased acetylcholine efflux in a similar fashion (up to 140% increase above baseline) in both cortical areas studied. Predictably, the higher concentration of neostigmine (0.5 microM) increased basal acetylcholine efflux by about 150% from levels observed with the lower neostigmine concentration (0.05 microM), but the concentration of local neostigmine had no effect on either the magnitude or the duration of the increased acetylcholine efflux following tactile stimulation. These results suggest that the pattern of acetylcholine release may be comparable in different areas of the cortex, supporting the idea that cholinergic projections from the basal forebrain to the cortex represent a globally regulated system. Furthermore, while the inclusion of neostigmine in perfusion fluid must be taken into account when interpreting acetylcholine efflux data, it appears that concentrations of up to 0.5 microM do not interfere fundamentally with the lability of cortical acetylcholine efflux in response to behavioural stimulation.
Liquid‐vapor equilibrium in the system helium‐methane

The present investigation is part of a program to provide accurate, low-temperature, phase-equilibria data for binary systems of both technical and theoretical importance. It was pointed out in a previous paper [1] that, particularly in the solid-vapor region, there was a deficiency of data for several systems of interest, specifically, the hydrogen and helium light-hydrocarbon systems. In that paper data were presented for the entire solid-vapor region of the hydrogen-methane system up to 150 atm.
Binding energy and catalysis by D-xylose isomerase: kinetic, product, and X-ray crystallographic analysis of enzyme-catalyzed isomerization of (R)-glyceraldehyde.

d-Xylose isomerase (XI) and triosephosphate isomerase (TIM) catalyze the aldose–ketose isomerization reactions of d-xylose and d-glyceraldehyde 3-phosphate (DGAP), respectively. d-Glyceraldehyde (DGA) is the triose fragment common to the substrates for XI and TIM. The XI-catalyzed isomerization of DGA to give dihydroxyacetone (DHA) in D2O was monitored by 1H nuclear magnetic resonance spectroscopy, and a kcat/Km of 0.034 M–1 s–1 was determined for this isomerization at pD 7.0. This is similar to the kcat/Km of 0.017 M–1 s–1 for the TIM-catalyzed carbon deprotonation reaction of DGA in D2O at pD 7.0 [Amyes, T. L., O’Donoghue, A. C., and Richard, J. P. (2001) J. Am. Chem. Soc. 123, 11325–11326]. The much larger activation barrier for XI-catalyzed isomerization of d-xylose (kcat/Km = 490 M–1 s–1) versus that for the TIM-catalyzed isomerization of DGAP (kcat/Km = 9.6 × 106 M–1 s–1) is due to (i) the barrier to conversion of cyclic d-xylose to the reactive linear sugar (5.4 kcal/mol) being larger than that for...
Ammonia caramels: Specifications and analysis

Twenty three UK commercially produced ammonia caramels and eight experimentally produced ammonia caramels have been analysed by a range of physical and chemical tests, which include solids content, nitrogen levels, colour intensity and pH. A statistical treatment of the results is reported.
Activity coefficients for dilute solid solutions of Al in Ni

We present a method for predicting activity coefficients in dilute binary solid solutions from first principles and apply it to Al in Ni. Accurate results require knowledge of the temperature dependencies of both enthalpy and entropy: with the latter being dominant. The activity coefficient of Al varies by 15 orders of magnitude over 400 K ⩽ T ⩽ 1700 K: whereas that for Ni only varies by
Luminescence excitation mechanisms in CdS from dependence of photoluminescence and thermoluminescence on persistent conductivity stored charge state

Abstract Experiments are reported on excitation-spectroscopic time-resolved photoluminescence and thermoluminescence in high resistivity CdS as a function of persistent conductivity associated stored-charge state.
Heterogeneity of DNA repair at the gene level

Abstract Overall genomic DNA repair efficiencies do not necessarily correlate with cellular sensitivities to radiation and other DNA-damaging agents. My colleagues and I have developed experimental apporoaches to measure DNA lesions and their repair in defined DNA sequences and we have discovered that for some types of damage, such as the cyclobutane pyrimidine dimers produced in DNA by ultraviolet ligh (UV), repair is highly selective for transcribed DNA strands in active genes: repair may be directly coupled to the transcription appartus. Freely diffusing repair complexes may account for the much lower repair efficiencies observed in silent genomic domains. The viability of mammalian cells may be ensured through selective repair of transcription-blocking DNA damage in essential, expressed genes rather than as a consequence of overall genomic repair. Persisting damage in non-transcribed domains may account for some cell-specific mutagenic and carcinogenic phenomena. In UV-irradiated cells from xeroderma pigmentosum (complementation group C) there is a deficiency in the removal of pyrimidine dimers from silent genomic domains, while in Cockayne's syndrome the effect appears to involve the preferential repair of active genes. In contrast to the cancer-prone characteristics of xeroderma pigmentosum the victims of Cockayne's syndrome do not suffer enhanced skin cancer induction by sunlight. Susceptibility to cancer and other biological endpoints is clearly dependent upon the fine structure detail of the DNA repair response.
Is alcoholism typology a predictor of both Alcoholics Anonymous affiliation and disaffiliation after treatment

Twelve Steps (TS) has demonstrated effectiveness; induction into Alcoholics Anonymous (AA) is a primary objective of TS and is a pivotal mechanism explaining its effectiveness. However, evidence suggests that, after treatment, dropout from AA is high. This study investigated whether alcohol problem severity predicted both AA affiliation and disaffiliation among clients receiving TS. This study of a Project MATCH sample included 453 alcohol-dependent clients randomly assigned to TS who reported AA attendance during treatment. Greater alcohol problem severity predicted AA attendance; opposite to prediction, less alcohol-impaired clients were more than twice as likely to discontinue AA attendance after treatment. When sustained AA attendance is desired, the evaluation of client pretreatment alcohol involvement may be useful for identifying potential AA dropout after TS treatment. Findings also indicate that, among treatment-seeking problem drinkers, AA dropout and disaffiliation are distinct, albeit correlated, constructs that require future investigation.
A Further Methodological Study of the Measurement of Interpersonal Aggression

Summary.-The 9 highest (HH) and 9 lowest (LH) scorers on the BussDurkee Hostility Inventory out of a sample of 115 males were placed into an identical situation in which they received mild shocks on 6 of GO trials. All Ss were angered by this procedure according to their scores on a self-report mood inventory. The HH and LH Ss significantly differed from each other on measures of number and intensity of shocks used and in terms of the first trial on which they retaliated. No apparent evidence was found for the notion that number and intensiry of shocks measure different processes of interpersonal aggression. Geen, Rakosky, and O'Neal ( 1968) measured interpersonal aggression in terms of both the number and intensity of shocks Ss administered to a confederate (C). They report that number of shocks is a better, more variable index of aggression and suggest that the rwo measures may reflect different processes. Geen, et al. speculate that number of shocks may measure not only aggressiveness but also the amount of aggression that S judges to be permissible in the situation while intensity of shock administered in retaliation may be more simp ly a measure of aggressiveness. One possible way of testing this notion is to provide S with a set, small number of shocks from C but allow S a large number of trials on which he can retaliate. If number of shocks is to a significant degree measuring a "retaliation in same kind" phenomenon, whereas intensity of shock level is more a measure of "intent to do harm," and if Ss have been sufficiently provoked by the procedure, then intensity rather than number should show the greater variance. The study reported here attempts to establish the above conditions and also provides a validation study for the Buss-DLirkee Hostility Inventory (1957). PROCEDURE Ss were 18 male undergraduates who participated in order to fulfill a req~lirement in general psychology. The Buss-Durkee Hostility Inventory ( 1957) was administered to all (110) male students in general psychology; the top (HH) 9 scorers (M = 57.17; range = 54-60) and the bottom (LH) 9 scorers (M = 14.02; range = 11-16) were used in this study. Each S was first given a mood questionnaire that measured self-reported anger. Then each S was introduced to the "other S," who was always the same male C following the same regimen. S and C were instructed to enter separate but adjoining rooms. S was told that the study concerned the "effects of stress on reaction time" and that
On Rekindling the Light of Public Space

the crucial distinction between modern democracy and the ancient forms that inspired it is, as Chantal Mouffe (1996) argues, pluralism not merely as a fact but as constitutive of its "very nature," then the successful functioning of modern democracy depends on its ability to give "positive status" to our differences, on its refusing appeals to the sort of objective unanimity that is "always revealed as fictitious and based on acts of exclusion" (246). Yet as the events of September 1 1 led us to confront what appeared as a threat of destruction by some incomprehensible and radically foreign other, American flags went up everywhere, there was much talk about "our way of life," and concerns for the valuing of difference gave way to the clear differentiation of us and them. Those who looked, acted, or even thought differently came under suspicion amid a new war on terror pitting the light of our own goodness against the "forces of darkness and evil" (Bush 2005).
On the role of the bacteriophage λ int gene product in site specific recombination

Abstract Integrative recombination of phage λ DNA occurs in extracts made from cells synthesizing int protein. In this paper we show that extracts of cells containing temperature-sensitive int protein are inactivated more rapidly by incubation at 38 °C than are wild-type extracts. This indicates that the int protein is directly involved in the recombination reaction.
Dynamic Force Generation within the Immune Synapse

Increasing evidence suggests mechanical forces modulate T cell function. In this report, we investigate forces applied by mouse CD4+ T cells onto an underlying substrate as a model of the interface between T cells and antigen presenting cells. Traction force microscopy was carried out using microfabricated arrays of elastomer (polydimethylsiloxane, Sylgard 184, PDMS) pillars; cells induce deflections of the pillars which can be measured and used to estimate force applied to each structure. We chose a pillar geometry of 1 micrometer diameter and 5-9 micrometer height. These pillars were coated with a 1:1 mix of activating antibodies to CD3 and CD28, which ligate and activate the TCR complex and costimulatory CD28 signal. Traction force microscopy carried out on mouse naive CD4+ T cells 1 hour after seeding revealed that naive cells exert forces onto these pillar arrays with magnitude on the order of 50 pN per structure. Moreover, force application by a given cell is periodic, with a cycle on the order of minutes. To investigate the physiological implications of these forces, we measured IL-2 secretion by T cells seeded onto planar PDMS substrates of varying rigidity, which was controlled by varying the ratio of base : curing agent, yielding bulk moduli of 2 MPa to 25 kPa. Substrates were coated with activating antibodies to CD3 and CD28 prior to cell seeding, and the per area concentration of antibodies varied less than 10% across the different moduli. Activation of naive T cells, measured as IL-2 secretion over six hours, was 50% greater on the stiffest vs. softest elastomers, and each condition was statistically different from all others (Kruskal-Wallis methods, alpha = 0.05). These results demonstrate a functional impact of mechanical forces on T cell activation, and reveal new dynamics of the immune synapse.
The linkers contribution to technology transfer

The role of an individual known as a ‘linker’ is examined and the similarities between his role and those of ‘gatekeeper’, ‘opinion leader’, and ‘innovator’ are discussed in detail. Not only are the similarities among these roles pointed out but also the unique characteristics of the ‘linker’ are clarified. A Linker Model for Technology Transfer is presented showing the value of a ‘linker’ to the parent and users organizations. Managerial endeavors to understand and promote technology transfer can be facilitated by the in-depth research presented.
Community Service Learning in Planning Education A Framework for Course Development

This article explains the importance of including service learning opportunities in the planning curriculum. Based on an interdisciplinary literature, the authors develop a four-part framework for service learning: an emphasis on the different ways of understanding; the value of human experience as a source of learning; the requirement for reflective thinking to transform experience into learning; and an ethical foundation that stresses citizenship to community, profession, and a larger public interest. This framework is then applied through a studio course that is taught annually in the Graduate Program in City and Regional Planning at the University of Memphis.
Critical high density fission--fusion plasmas

The implosion-induced compression of a pellet consisting of fissionable material, such as U 233, U 235 or Pu 239, to high densities by a laser-, relativistic electron-, or ion-beam is expected to lead to very small critical masses which can be furthermore substantially reduced by simultaneously compressing the pellet together with a neutron reflector. This method opens the prospect for micro-fission-explosions to be used for controlled power production as for a safe fast breeder reactor or for rocket propulsion. Furthermore, if the neutron reflector consists of thermonuclear material, such as T—D, the method can be used for the controlled release of thermonuclear energy. There the fission chain reaction not only will assist in the ignition of the thermonuclear reaction but in turns the fusion neutrons will accelerate the fission chain reaction to a very fast pace. In this case therefore, the fission chain reaction and the fusion thermonuclear reaction are coupled together with an expected greatly increased energy output.
Models for the HIV infection and AIDS epidemic in the United States

Statistical models of the HIV infection epidemic in the U.S. which account for the observed incidence of AIDS cases in the years 1978–1987 are considered. The models assume a known distribution of times from infection to AIDS. The best model estimates that there were approximately 563,000 to 1,110,000 individuals infected in the U.S. in April 1987. These estimates do not take into account underreporting of AIDS cases. The sensitivity of the conclusions to the model's assumptions is ascertained by investigating a variety of parametric models for the infection epidemic, a variety of likely distributions for the time from infection to AIDS, and some plausible alternatives for the history of AIDS cases in the U.S. It is concluded that there is too much uncertainty in the data and the models to be able to give highly accurate predictions of the number of people currently infected in the U.S., however, the results from the best fitting models suggest that there are less than the 1 to 1·5 million infected as estimated by the Centers for Disease Control. A Bayesian scheme is suggested for incorporating the uncertainty in the models.
Extrinsic cotton effect of isothiocyanatofluorescein-labelled hyaluronic acid

Abstract Circular dichroism and fluorescence measurements have been carried out on isothiocyanotofluorescein-labelled hyaluronic acid and chondroitins. The labelling procedure causes a limited degradation or change in the secondary structure of the polymer. Upon interaction with the dye, hyaluronic acid displayed an extrinsic Cotton effect in the near-u.v. region where neither the polymer nor the dye show any circular dichroism. Chondroitin, structurally similar to hyaluronic acid but differing only in the C-4 hydroxyl group configuration of the amino sugar, failed to show such Cotton effect. The appearance of the extrinsic dichroism may be evidence of a long-range order in the solution conformation of hyaluronate at neutral pH. The absence of an extrinsic Cotton effect in chondroitin and chondroitin sulphate may indicate that these polymers lack such conformational order. Fluorescence measurements of the labelled polymers show some differences among them in quantum yield, lifetime and polarization values; the differences are analysed in terms of the subtle difference in environments of the labelled dye molecules and in the tertiary structure of the polymer.
Single cell gene expression profiling of cortical osteoblast lineage cells

In tissues with complex architectures such as bone, it is often difficult to purify and characterize specific cell types via molecular profiling. Single cell gene expression profiling is an emerging technology useful for characterizing transcriptional profiles of individual cells isolated from heterogeneous populations. In this study we describe a novel procedure for the isolation and characterization of gene expression profiles of single osteoblast lineage cells derived from cortical bone. Mixed populations of different cell types were isolated from adult long bones of C57BL/6J mice by enzymatic digestion, and subsequently subjected to FACS to purify and characterize osteoblast lineage cells via a selection strategy using antibodies against CD31, CD45, and alkaline phosphatase (AP), specific for mature osteoblasts. The purified individual osteoblast lineage cells were then profiled at the single cell level via nanofluidic PCR. This method permits robust gene expression profiling on single osteoblast lineage cells derived from mature bone, potentially from anatomically distinct sites. In conjunction with this technique, we have also shown that it is possible to carry out single cell profiling on cells purified from fixed and frozen bone samples without compromising the gene expression signal. The latter finding means the technique can be extended to biopsies of bone from diseased individuals. Our approach for single cell expression profiling provides a new dimension to the transcriptional profile of the primary osteoblast lineage population in vivo, and has the capacity to greatly expand our understanding of how these cells may function in vivo under normal and diseased states.
The conservation of unionid mussels in Louisiana rivers: diversity, assemblage composition and substrate use

1. To aid in their conservation, unionid mussel assemblages were surveyed in three relatively unstudied rivers in south-eastern Louisiana. 2. Although total species richness varied among rivers, species diversity (as estimated both by Shannon-Weaver H′ and rank-abundance curves) was fairly similar. 3. Assemblage composition varied among the rivers, with the West Pearl River having the most dissimilar group of species. The endangered inflated heel splitter, Potamilus inflatus, was found only in the lower Amite River. 4. The most common species had size distributions skewed towards larger individuals, but small individuals were collected (including the inflated heel splitter), indicating successful recruitment. 5. Mussels were more common in silt than in sand or gravel, perhaps because fine sediments are more stable through time in these river systems. 6. The greatest threat to these assemblages is gravel mining in the upper reaches of the rivers. At the present time only rivers with endangered species, or that have been declared scenic rivers, have any protection from gravel mining. Copyright © 2001 John Wiley & Sons, Ltd.
Determining plastic properties of a material with residual stress by using conical indentation

Abstract Instrumented indentation is a popular method for determining mechanical properties in engineering materials. However, there are several shortcomings and challenges involved with correctly interpreting the test results. We propose here a unified method for evaluating instrumented indentation testing conducted on a material that exhibits both strain hardening under yielding and which is subjected to uniform, equi-biaxial residual stresses. The proposed method is based on extensive finite element simulations that relate the parameter-space spanned by Young’s modulus, yield strength, strain hardening and residual stress, to the response from the indentation test. Based on reverse analysis, the proposed method can be used to determine two unknown quantities, such as yield strength and strain hardening. The technique involves utilizing the concept of representative strain and plural indenter-shapes.
Expression of the Tuberous Sclerosis 2 Gene Product, Tuberin, in Adult and Developing Nervous System Tissues

Abstract Tuberous sclerosis (TS) is an autosomal dominant disorder in which affected individuals manifest mental retardation, seizures, and a variety of benign and malignant tumors. The TSC2 tumor suppressor gene was recently identified by positional cloning and its protein product, tuberin, shown to represent one member of the rap GTPase activating protein (rapGAP) family. In order to determine the contribution of tuberin to the development of mental retardation and seizures in patients with TS, we examined the expression of tuberin in adult and developing nervous system tissues. Since tuberin is the second rapGAP found in the nervous system, the expression of tuberin was compared to the expression of rapGAP, rap1, and rap2. In this study, we demonstrate that tuberin is expressed at greatest levels in the spinal cord and cerebellum as opposed to rapGAP, which is not enriched in these tissues. Tuberin expression in the adult CNS is restricted to the olfactory bulb, several CNS neuronal populations, brainstem nuclei, cerebellar Purkinje cells, and motor neurons in the ventral spinal cord. In contrast, rapGAP is expressed in many different cell types in the adult CNS, but not in cerebellar Purkinje cells or motor neurons in the ventral spinal cord. However, there is significant expression of rapGAP in astrocytes. The restricted distribution of tuberin expression relative to rap1 and rapGAP suggests that tuberin may be the primary rap1 regulator in a subpopulation of CNS neurons.
MAGNET: MicroArray Gene expression and Network Evaluation Toolkit.

MicroArray Gene expression and Network Evaluation Toolkit (MAGNET) is a web-based application that provides tools to generate and score both protein–protein interaction networks and coexpression networks. MAGNET integrates user-provided experimental measurements with high-throughput proteomic datasets, generating weighted gene–gene and protein–protein interaction networks. MAGNET allows users to weight edges of protein–protein interaction networks using a logistic regression model integrating tissue-specific gene expression data, sub-cellular localization data, co-clustering of interacting proteins and the number of observations of the interaction. This provides a way to quantitatively measure the plausibility of interactions in protein–protein interaction networks given protein/gene expression measurements. Secondly, MAGNET generates filtered coexpression networks, where genes are represented as nodes, and their correlations are represented with edges. Overall, MAGNET provides researchers with a new framework with which to analyze and generate gene–gene and protein–protein interaction networks, based on both the user’s own data and publicly available –omics datasets. The freely available service and documentation can be accessed at http://gurkan.case.edu/software or http://magnet.case.edu.
Robotic partial nephrectomy: The new horizon

Abstract Background There has been an exponential growth in the reporting of series of robotic partial nephrectomy (RPN). We review the technique of RPN and the outcomes from large single-centre series of RPN. Methods We searched databases to identify original articles related to RPN. For the technical aspects, we describe our technique and provide a general review of previous work. For outcomes, we reviewed previous reports using more rigid criteria, including only single-institution studies with at least 50 patients undergoing RPN. Results We found seven retrospective studies that met our criteria, with a total of 701 patients. Mean tumour size was 2.8 cm, with an average R.E.N.A.L. score ( R adius, tumour size as maximum diameter; E xophytic/endophytic properties of the tumour, N earness of tumour deepest portion to the collecting system or sinus, A nterior, a/posterior, p, descriptor, and the L ocation relative to the polar line) of 6.8. The mean warm ischaemia time was 21 min and mean operative duration was 196 min. The mean estimated blood loss was 182 mL, with a 7.4% transfusion rate. The conversion rate was 1.7% and the postoperative complication rate was 14%. The mean length of stay was 3.6 days. There were positive surgical margins in 1.7% of patients. The mean decrease in renal function was 5.4% and the mean follow-up was 8.4 months. Conclusions RPN is feasible and safe for different levels of complexity of renal tumours. Perioperative outcomes are comparable to those found with more established techniques. Future studies should compare different approaches and prioritise prospective and randomised designs.
Predicting Variations in Math Performancein Four Countries Using TIMSS

Although international comparisons of average student performance are a staple of U.S. educational debate, little attention has been paid to cross-national differences in the variability of performance. It is often assumed that the performance of U.S. students is unusually variable or that the distribution of U.S. scores is left-skewed – that is, that it has an unusually long ‘tail' of low-scoring students – but data from international studies are rarely brought to bear on these questions. This study used data from the Third International Mathematics and Science Study (TIMSS) to compare the variability of performance in the U.S., Australia, France, Germany, Hong Kong, Korea, and Japan; investigate how this performance variation is distributed within and between classrooms; and explore how well background variables predict performance at both levels. TIMSS shows that the U.S. is not anomalous in terms of the amount, distribution, or prediction of performance variation. Nonetheless, some striking differences appear between countries that are potentially important for both research and policy. In the U.S., Germany, Hong Kong, and Australia, between 42 and 47 percent of score variance was between classrooms. At the other extreme, Japan and Korea both had less than 10 percent of score variance between classrooms. Two-level models (student and classroom) were used to explore the prediction of performance by social background variables in four of these countries (the U.S., Hong Kong, France, and Korea). The final models included only a few variables; TIMSS lacked some important background variables, such as income, and other variables were dropped either because of problems revealed by exploratory data analysis or because of a lack of significance in the models. In all four countries, these sparse models predicted most of the between-classroom score variance (from 59 to 94 percent) but very little of the within-classroom variance. Korea was the only country in which the models predicted more than 5 percent of the within-classroom variance in scores. In the U.S. and Hong Kong, the models predicted about one-third of the total score variance, and almost all of this prediction was attributable to between-classroom differences in background variables. In Korea, only 19 percent of total score variance was predicted by the model, and most of this most of this was attributable to within-classroom variables. Thus, in some instances, countries differ more in terms of the structure and prediction of performance variance than in the simple amount of variance. TIMSS does not provide a clear explanation of these differences, but this paper suggests hypotheses that warrant further investigation.
Effect of resistance exercise volume and complexity on EMG, strength, and regional body composition

This study was designed to examine the effects of a 12-week resistance training program using single versus multiple sets of a complex versus simple exercise on EMG, strength and regional body composition. Twenty-eight untrained men ( n=15) and women ( n=13) performed resistance training twice per week. Group 1 (S-1, n=9) performed one set of a leg press (LP) and bicep curl (BC) exercise, group 2 (M-6, n=9) performed six sets of a LP and BC exercise, and group 3 (C, n=10) was the control group. One-repetition maximums (1RMs) and EMG were measured in the LP and BC during pre-, mid-, and post-training. Lean body mass of the legs and arms were measured pre- and post-training by dual energy X-ray absorptiometry. Results of the study indicated that both S-1 and M-6 groups significantly increased percentage strength pre- to post-training in both the LP and BC [S-1 pre-/post-LP=41.2 (23.7)%, BC=8.5 (6.71)%; M-6 pre-/post-LP=52.6 (12.6)%, BC=22.8 (15.6)%; mean (SD)]. However, compared to S-1, M-6 showed a significantly greater increase in percentage strength in the BC ( P<or=0.05) from pre- to post-testing. Results also showed that M-6 produced a significant increase in biceps (single-joint) muscle EMG values pre- to mid-testing compared to S-1. There were no significant differences found in lean muscle mass gains for the legs or arms in either training group. The data from this study suggest that multiple sets produce a greater increase in percentage strength gain for a simple exercise. It is possible that some type of neural mechanism is responsible for the observed difference.