cssi/SciSciGPT-SciSciNet huggingface dataset:
Complete experimental test of kinetic models for rapid alloy solidification

The interface response functions for rapid solidification of a non-dilute binary alloy were measured in the regime of partial solute trapping, where substantial discrepancies exist among predictions for the interfacial undercooling in various models. We used pulsed laser melting of Si-As on insulating substrates to enforce planar solidification spanning the velocity range 0.2-2 m/s. Nanosecond-resolution electrical measurements of the time-dependent melt depth and of the electrical resistivity of a buried Pt thin film thermometer permitted us to determine the solidification velocity and the temperature of the crystal/melt interface. With composition-depth profile measurements we also determined the nonequilibrium partition coefficient. The measured velocity-dependence of the interface temperature and partition coefficient are quan- titatively consistent with the continuous growth model without solute drag of M. J. Aziz and T. Kaplan (Acta Metall. 36, 1335 (1988)) and are qualitatively and quantitatively inconsistent with all models exhibiting a significant solute drag effect. Elements of a potential explanation are proposed using the solute drag model of M. Hillert and B. Sundman (Acta Metall. 24, 731 (1976)) to investigate the origin of the solute drag effect in terms of irreversible processes occurring within a diffuse interface. © 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.
Thinking through sport, analyzing whiteness

Abstract In the lead article of this issue, ‘Sport as Contested Racial/Ethnic Terrain: Processes of Racialization in Dutch Sport Media and Sport Policy,’ Jacco Van Sterkenburg and Annelies Knoppers offer a cogent analysis of racialized sporting discourse in the Netherlands demonstrating to a wider audience the important role that sport plays in promoting contemporary meanings and practices regarding race/ethnicity. This commentary points out some key issues raised by Van Sterkenburg and Knoppers, notes some gaps in their argument while also discussing questions that the authors raise for those interested in challenging the power of whiteness in and beyond the world of sport.
One-electron spectral weight of the doped two-dimensional Hubbard model.

We have calculated the single-particle density of states [ital N]([omega]) and the spectral weight [ital A]([bold p],[omega]) for the doped two-dimensional Hubbard model by combining quantum Monte Carlo simulations with the maximum-entropy analytic continuation technique. We present results for various values of the doping, temperature, and Coulomb repulsion [ital U]. For sufficiently strong Coulomb repulsions and near half filling, a Mott-Hubbard pseudogap exists. In this case, we find that a peak develops at the top of the lower Hubbard band near the Fermi level at temperatures of order of the hopping [ital t]. The structure of this peak is similar to that seen in the infinite dimensional Hubbard model.
Comparison of the adsorption of N2 on Ru(1 0 9) and Ru(0 0 1) – A detailed look at the role of atomic step and terrace sites

We present a direct side-by-side comparison of the adsorption and desorption of nitrogen on the atomically-stepped Ru(1 0 9) surface and the atomically-flat Ru(0 0 1) surface. Both infrared reflection absorption spectroscopy (IRAS) and temperature programmed desorption (TPD) are employed in this study, along with density functional theory (DFT). We find that the chemisorptive terminal binding of N2 is stronger on the atomic step sites than on the terrace sites of Ru(1 0 9) as indicated by TPD and by a reduction of the singleton vibrational frequency, ν(N2), by 9 cm-1, comparing steps to terraces. In addition, we find that metal–metal compression effects on the terrace sites of Ru(1 0 9) cause stronger binding of N2 than found on the Ru(0 0 1) surface, as indicated by a reduction of the terrace-N2 singleton vibrational frequency by 11 cm-1 when compared to the singleton N2 mode on Ru(0 0 1). These spectroscopic results, comparing compressed terrace sites to Ru(0 0 1) sites and confirmed by TPD and DFT, indicate that N2 bonds primarily as a σ-donor to Ru. Using equimolar 15N2 and 14N2, it is found that dynamic dipole coupling effects present at higher N2 coverages may be partially eliminated bymore » isotopically detuning neighbor oscillators. These experiments, considered together, indicate that the order of the bonding strength for terminal-N2 on Ru is: atomic steps > atomic terraces > Ru(0 0 1). DFT calculations also show that 4-fold coordinated N2 may be stabilized in several structures on the double-atom wide steps of Ru(1 0 9) and that this form of bonding produces substantial decreases in the N2 vibrational frequency and increases in the binding energy, compared to terminally-bound N2. These highly coordinated N2 species are not observed by IRAS.« less
Improving cooperative trajectory mapping applications with encounter-based error correction

Cooperative trajectory mapping is an emerging technique that allows users to create such a map by using data that are collected from each other's mobile phones. This technique has been proposed for many applications, such as people localisation, public transportation tracking and traffic monitoring. Unlike the traditional Global Positioning System, cooperative trajectory mapping only requires information about the departure distance and moving direction from the previously reported position. This avoids problems such as the high-energy consumption of GPS and weak GPS signals in indoor conditions. However, the new technique also brings about other problems, such as measurement errors in cooperative trajectory mapping, which is when a measurement error causes the spatial relations among users to be wrong. We propose an encounter-based error correction algorithm to efficiently reduce measurement errors. Extensive simulation experiments are carried out to validate our solutions.
Preservation potential of sedimentary event layers

Preservation potential of sedimentary event layers (e.g., ash layers or tempestites) is a function of net sedimentation rate and biogenous mixing rate. Previous studies that have used an inverse Peclet number to scale the problem in terms of advection or diffusion are in error due to the improper inclusion of the surface mixed layer thickness as the sole length scale. Herein, focus is on time scales. If the transit time (i.e., time required to advect the signal through the biologically active zone) is less than the dissipation time (i.e., time required to destroy the signal), then some fraction of the original signal is preserved. A simple quantitative model, based on the diffusion analogy of sediment mixing, estimates the actual percentage of preserved signal under various combinations of sedimentation rate, mixing rate, and event layer thickness.
Interpreting the COURAGE trial. It takes COURAGE to alter our belief system.

We found that as an initial management strategy in patients with stable coronary artery disease, percutaneous coronary intervention did not reduce the incidence of death, myocardial infarction, or other major cardiovascular events when added to optimal medical therapy.
Using EBCAI structured appraisal abstracts as a resource in clinical supervision

Speech-language pathologists (SLPs) participating in supervisory processes in a clinical setting often face challenges, including an expanding scope of professional practice and constraints associated with time and resources. Evidence-Based Communication Assessment and Intervention (EBCAI) can guide a supervisor and supervisee in determining effective treatment options for a variety of populations and can save the supervisor time in researching disorders and appraising treatment methods, as the appraisals have already been completed. This article provides brief illustrations that describe how a supervisor might use EBCAI commentaries in clinical instruction. Although other resources on evidence-based practices should not be ignored, EBCAI appraisals provide an excellent starting point in generating and evaluating evidence-based practices in speech-language pathology. Source of funding: No source of funding reported.
Alcohol Assessment in Psychiatric Patients

Alcohol use disorders in persons with co-occurring psychiatric disorders are associated with high rates of psy-chosocial instability and poorer treatment outcomes. Thus, assessment of alcohol use and abuse should become an integral part of psychiatric care. Because setf-report-based measures are frequently used, issues of reliability and validity in this population should be critically examined. The purpose of this article is to review and critique the existing empirical literature that has evaluated the psychometric integrity of self- report-based measures in psychiatric settings, and to outline a research agenda that promises to enhance the accuracy of alcohol assessment by persons receiving psychiatric treatment.
Comments on a paper by D. Meisel entitled 'Identification of a solar X-ray source using D-layer ionization behavior during an eclipse'

Critical review of Meisel paper on solar X ray source identification using D layer ionization behavior during eclipse
Philosophy, Poetry, Parataxis

At the heart of the relationship between philosophy and poetry, and of the philosophical and the literary tout court, is the relationship between poetry and prose. In the increasingly influential work of Giorgio Agamben, whose impact continues to grow across a wide range of disciplines, the relationship between philosophy and poetry, poetry and prose, receives renewed attention and significance. Situating Agamben's philosophical, poetic prose in relation to the legacy of the prose poem from Charles Baudelaire through Walter Benjamin and Rosmarie Waldrop, “Philosophy, Poetry, Parataxis” explores the implications of what Agamben calls “whatever being” or “whatever singularity” for our understanding of the potentialities inherent in the relationship between contemporary writing practices and what Agamben calls The Coming Community. In contributing to the development of innovative, alternative forms of textuality at once “philosophical” and “poetic,” contemporary writers such as Agamben and Waldrop share an u...
Male reproductive proteins and reproductive outcomes

Male reproductive proteins (MRPs), associated with sperm and semen, are the moieties responsible for carrying male genes into the next generation. Evolutionary biologists have focused on their capacity to control conception. Immunologists have shown that MRPs cause female genital tract inflammation as preparatory for embryo implantation and placentation. These observations argue that MRPs are critically important to reproductive success. Yet the impact of male reproductive proteins on obstetrical outcomes in women is largely unstudied. Epidemiologic and clinical observations suggest that shorter-duration exposure to MRPs prior to conception may elevate the risk for preeclampsia. A limited literature has also linked sexual behavior to bacterial vaginosis and preterm birth. We offer a clinical opinion that MRPs may have broad implications for successful reproduction, potentially involved in the composition of vaginal microflora, risks of preterm birth and preeclampsia, and success of assisted reproduction.
Surface and Thermal Effects on the Pull-In Behavior of Doubly-Clamped Graphene Nanoribbons Under Electrostatic and Casimir Loads

In this study, a comprehensive analytical model is established based on Euler–Bernoulli beam theory with von Karman geometric nonlinearity to investigate the effect of residual surface tension, surface elasticity, and temperature on the static pull-in voltages of multilayer graphene nanoribbon (MLGNR) doubly-clamped beams under electrostatic and Casimir forces and axial residual stress. An explicit closed-form analytical solution to the governing fourth-order nonlinear differential equation of variable coefficients is presented for the static pull-in behavior of electrostatic nanoactuators using a Fredholm integral equation of the first kind. The high accuracy of the present analytical model is validated for some special cases through comparison with other existing numerical, analytical, and experimental models. The effects of the number of graphene nanoribbons (GNRs), temperature, surface tension, and surface elasticity on the pull-in voltage and displacement of MLGNR electrostatic nanoactuaotrs are investigated. Results indicate that the thermal effect on the pull-in voltage is significant especially when a smaller number of GNRs are used. It is found that the surface effects become more dominant as the number of GNRs decreases. It is also demonstrated that the residual surface tension exerts a greater influence on the pull-in voltage in comparison with the surface elasticity.
A Kinematic Approach to Determining the Optimal Actuator Sensor Architecture for Space Robots

Autonomous space robots will be required for such future missions as the construction of large space structures and repairing disabled satellites. These robots will need to be precisely controlled. However, factors such as manipulator joint/actuator friction and spacecraft attitude control thruster inaccuracies can substantially degrade control system performance. Sensor-based control algorithms can be used to mitigate the effects of actuator error, but sensors can add substantially to a space systemâs weight, complexity, and cost, and reduce its reliability. Here, a method is presented to determine the sensor architecture that uses the minimum number of sensors that can simultaneously compensate for errors and disturbance in a space robotâs manipulator joint actuators, spacecraft thrusters, and reaction wheels. The placement and minimal number of sensors is determined by analytically structuring the system into âcanonical chainsâ that consist of the manipulator links and spacecraft with force/torque sensors placed between the space robotâs spacecraft and its manipulators. These chains are combined to determine the number of sensors needed for the entire system. Examples of one- and two-manipulator space robots are studied and the results are validated by simulation.
A Replication of the Technical Adequacy of the Student Subjective Wellbeing Questionnaire

The present study reports on a replication of the technical adequacy of the Student Subjective Wellbeing Questionnaire (SSWQ), which is a 16-item self-report instrument for assessing youth’s academic efficacy, educational purpose, joy of learning, and school connectedness, with a sample of adolescents in Grades 6 to 7 (N = 438). Findings confirmed the SSWQ’s latent factor structure as well as the reliability and distribution of its factors/scales. Results also indicated that SSWQ scores had concurrent associations with youths’ self-reported academic achievement, cumulative risks, and cumulative assets. Overall, this study provides a strong, positive replication of the technical adequacy of the SSWQ, suggesting that it is a psychometrically sound measure for school psychological research and, potentially, practice. Prior to recommending the SSWQ for practical purposes in schools, however, applied research is needed to investigate issues related to incremental validity and treatment utility.
Acute pain treatment for older adults hospitalized with hip fracture: current nursing practices and perceived barriers

This article examines acute pain management practices for patients 65 years of age and older who were hospitalized during 1999 for hip fracture. Data were collected from the medical records of patients (N = 709) admitted to 12 hospitals in the Midwest and from questionnaires on pain practices completed by nurses (N = 172) caring for these patients. The major variables examined were (1). pharmacological and nonpharmacological treatments for acute pain in hospitalized elders, (2). nurses' perceived stage of adoption for avoiding meperidine use and for administering analgesics around-the-clock, and (3). nurses' perceived barriers to optimal treatment of acute pain in elders. Acetaminophen was the most frequently administered analgesic, but administered doses were far less than the maximum daily recommended dose. More than one third (39%) of the nurses reported that they always avoided the use of meperidine, and over half reporting avoiding its use sometimes. However, the majority of patients (56.8%) received at least one dose of meperidine, even though evidence suggests that other analgesic agents are more appropriate for treatment of acute pain in elders. Only 27% of patients received patient-controlled analgesia, and only 22.3% of patients received around-the-clock administration during the first 24 hours after admission of analgesics that had been ordered on a prn basis. The majority of nurses were aware that around-the-clock administration of analgesics was preferable, but only 33.7% were persuaded (believed) that this method should be used. Intramuscular injection was used for 52.2% of patients, even though this route is not recommended for older adults. The most frequently used nonpharmacological intervention was repositioning, followed by use of pressure relief devices and cold application. Nurses reported difficulty contacting physicians and difficulty communicating with them about type and/or dose of analgesics as the greatest barriers to pain management. Findings from this multi-site study show that active and focused "translation" interventions are needed to promote adoption of evidence-based acute pain management practices by health care providers.
Toward a normative‐contextualist theory of technology

Observing an impasse within research on “information age”1 technologies, the paper borrows from current moral philosophy as a basis for reorienting these discussions. Exploration of a contextualist position produces a call for a normative stance that privileges concern for the technological impact upon the conditions of self‐knowledge over concern with conditions of access or choice. An ethnographic, diagnostic approach is advocated for analyzing social meanings associated with contemporary technologies; and a normatively‐based theoretical framework is outlined to guide research into how communications technologies may serve or impede the goals of identity, orientation, self‐knowledge, and community.
Accuracy and precision of estimating intervention efficacy when the timing of observed events differ by treatment arm

Randomization in clinical trials minimizes differences between treatment arms, allowing observed treatment differences to be attributable to an intervention. For prospective clinical trials, we examine the effects on inference when other specified treatment arm differences are also present. These differences are imposed using three measures: time between the unobserved failure event (e.g., HIV infection) and its detection, visit schedule adherence and dropout. Our context of interest is trials with non-recurrent time-to-event outcomes and fixed visit intervals, where treatment efficacy is measured either by a hazard ratio or by a ratio of cumulative incidence functions. Moderate treatment differences in visit adherence, either through missed visits or additional unscheduled visits, were not found to cause substantial bias or to reduce power. However, both differential loss to follow-up (when coincidentally dependent on risk of failure) and differential time between event and detection should be of concern in designing clinical trials. Efforts to re-capture subjects at the end of study for failure assessment are helpful in some contexts, and may be considered in study planning.
Correlation spectroscopy as a probe of excitation and ionization mechanisms in the inductively coupled plasma

Abstract Correlations between intensity fluctuations in atomic and ionic emission lines were used as indicators of ionization and excitation mechanisms in the inductively coupled plasma. Ionic lines excited by charge exchange were positively correlated with neutral atom emission, while those excited by electron impact showed a negative correlation. An analog correlator was constructed to allow rapid measurement of such correlations over a broad range of wavelengths and as a function of position in the plasma. Results obtained to date suggest that charge exchange contributes significantly to the excitation and ionization of Mg, Y, Ti and V in the inductively coupled plasma.
Medication therapy management: its relationship to patient counseling, disease management, and pharmaceutical care.

Abstract Objectives To delineate the relationship, including similarities and differences, between medication therapy management (MTM) and contemporary pharmacist-provided services, including patient counseling, disease management, and pharmaceutical care, to facilitate the continued evolution of commonly used language and a standard of practice across geographic areas and practice environments. Summary Incorporation of MTM services into the array of Medicare-funded services affords an opportunity for pharmacists to develop direct patient care services in the community. Defining the role of MTM within the scope of pharmacist-provided patient care activities, including patient counseling, disease management, and all currently provided pharmacy services is essential to the delineation of a viable and sustainable practice model for pharmacists. The definitions of each of these services are offered, as well as comparisons and contrasts of the individual services. In addition to Medicare-eligible patients, MTM services are appropriate for anyone with medication-related needs. MTM is offered as an all-encompassing model that incorporates the philosophy of pharmaceutical care, techniques of patient counseling, and disease management in an environment that facilitates the direct collaboration of patients, pharmacists, and other health professionals. Conclusion Defining the role of MTM within the current patient care models, including patient counseling, disease management, and all who provide pharmacy services, is essential in delineating a viable and sustainable practice model for pharmacists.
Higher-order conditioning in the monkey.

(1957). Higher-Order Conditioning in the Monkey. The Journal of General Psychology: Vol. 56, No. 1, pp. 67-72.
On discrete-time polynomial systems

Abstract : Algebraic geometry is the natural tool for the study of a broad class of discrete-time nonlinear systems. This class consists of those systems described by polynomial transitions and polynomial constraints in the state set. The examples of nonlinear systems whose structure theory is today at all understood (bilinear input/output, bilinear in the state) are instances of this broad class of systems. In the present paper we show that a number of finiteness results can be derived for systems via the application of standard methods in algebraic geometry. In particular, we obtain practical tests for equality of behaviors, reachability and observability. Finally, we prove a preliminary result which gives conditions under which two systems with same input/output behavior are isomorphic. (Author)
Interface engineering in mullite fiber/mullite matrix composites

Mullite fiber/mullite matrix composites are attractive because of their inherent oxidation resistance at high temperatures. Mullite has better creep resistance than alumina. However, chemical interactions between oxides are often very severe; with the result no gain is made over monolithic mullite in terms of toughness. Even in the absence of chemical bonding, a strong mechanical bond component may be present. This originates from radial compressive stress due to thermal expansion mismatch and/or the surface roughness of interface. Thus, the microstructure and behavior of the interface region are the key factors in obtaining an effective control of damage in composites and enhancement of toughness. This body of work on mullite/mullite composites shows the feasibility of producing fully dense, tough oxide/oxide composites by interface engineering. Coatings such as BN alone or SiC/BN double coating function effectively for mullite fiber/mullite matrix composites in that they provide a nonbrittle fracture and increased work of fracture at room temperature. It would appear that for use at high temperatures in air, one needs to identify structural analogs of BN among oxides.
Local sentries for class switching.

Epithelial cells responding to inflammatory stimuli can initiate class switching and antibody secretion in naive B cells. TSLP, BAFF and SLPI are epithelial cell–derived local regulators of effector B cell responses in mucosal environments.
Surgical Treatment of Stage I Melanoma

We must continue a critical reexamination of traditional treatment of any disease in the light of current understanding of its natural history. Since the inclusion of a regional lymph node dissection in the treatment of melanoma without palpable regional nodes remains a point of debate, 1 it is crucial that any attempt to answer this point be made in accordance with current concepts of melanoma histogenesis and pathological characteristics. The excellent clinicopathological correlation between morphologic presentation of the melanoma and patient survival, and between depth of invasion of the melanoma and survival, demonstrated first by Clark's group in Boston 2 and confirmed by McGovern in Australia, 3 cannot be ignored in evaluating efficacy of any therapeutic regimen (Table 1). Clark's terminology is precise (Figure) and suggests that usage of the word "level" instead of "stage" of invasion be adopted to avoid the ambiguity that arises with the usage of "stage,"
Influence of cold soil and snowcover on photosynthesis and leaf conductance in two Rocky Mountain conifers.

The influence of cold soil and snowcover on photosynthesis and conductance of Picea engelmannii and Pinus contorta was investigated early in the growing season in the Medicine Bow Mountains, Wyoming, USA. Trees of both species growing in cold soil ( 10°C). In cold soils leaf conductance of both species was lower, but more so in Pinus, leading to lower intercellular CO2 concentrations and greater stomatal limitation of photosynthesis. Soil temperature had no effect on predawn and midday shoot water potentials of Pinus and Picea and lower photosynthesis and conductance did not appear to be a result of lower bulk shoot water potential. Predawn, as well as midday, water potentials of Pinus were consistently higher than Picea suggesting that Pinus may have deeper roots, although trenching experiments indicated young Picea trees have more extensive lateral root systems than similar sized Pinus trees. Young Picea trees (<2 m in height) in snowbanks were capable of utilizing warmer soil 4 m from their base. Under similar conditions Pinus in snowbanks had lower photosynthesis and conductance than controls and Pinus did not appear capable of utilizing warmer soils nearby. Under full sunlight, PPFD reflected from the snow surface was 400-1400 μmol m-2 s-1 higher than from snow-free surfaces. This reflected light resulted in a 10%-20% increase in photosynthesis of Picea. The beneficial effect of reflected light was apparent whether or not photosynthesis was reduced by low soil temperatures.
Managing multiple speech‐enabled applications in a mobile handheld device

– Mobile handheld devices, such as cellular phones and personal digital assistants, are inherently small and lack an intuitive and natural user interface. Speech recognition and synthesis technology can be used in mobile handheld devices to improve the user experience. The purpose of this paper is to describe a prototype system that supports multiple speech‐enabled applications in a mobile handheld device., – The main component of the system, the Program Manager, coordinates and controls the speech‐enabled applications. Human speech requests to, and responses from, these applications are processed in the mobile handheld device, to achieve the goal of human‐like interactions between the human and the device. In addition to speech, the system also supports graphics and text, i.e., multimodal input and output, for greater usability, flexibility, adaptivity, accuracy, and robustness. The paper presents a qualitative and quantitative evaluation of the prototype system. The Program Manager is currently designed to handle the specific speech‐enabled applications that we developed., – The paper determines that many human interactions involve not single applications but multiple applications working together in possibly unanticipated ways., – Future work includes generalization of the Program Manager so that it supports arbitrary applications and the addition of new applications dynamically. Future work also includes deployment of the Program Manager and the applications on cellular phones running the Android Platform or the Openmoko Framework., – This paper presents a first step towards a future human interface for mobile handheld devices and for speech‐enabled applications operating on those devices.
Gender differences in the sequelae of hospitalization for acute myocardial infarction among older adults.

OBJECTIVE: To examine the effect of gender differences among older adults hospitalized for an acute myocardial infarction (AMI) on subsequent health outcomes. DESIGN: Secondary analysis of the Longitudinal Study on Aging. Data from baseline interviews (1984) and three biennial (1986, 1988, and 1990) re-interviews were linked to Medicare hospitalization and National Death Index records for 1984–1991. PARTICIPANTS: A total of 6071 community-dwelling adults aged 70 years or older at baseline. METHODS: Pooled and stratified multivariable models were used to examine gender differences in the independent effects of being hospitalized for an AMI on all- cause mortality, the risk and volume of subsequent hospitalization, and increases in the number of functional limitations. Two comparison groups were used. RESULTS: Three hundred fifty-seven AMI cases (6%; 172 women and 185 men) were compared with 3976 hospitalized controls and 1738 nonhospitalized controls. The risk of all-cause mortality for AMI cases was greater than that for either hospitalized controls or nonhospitalized controls (referent), and this increased risk was significantly (P < .001) stronger for women (adjusted hazards ratio (AHR) = 14.24, 95%CI = 10.99, 18.46) than for men (AHR = 9.91, 95%CI = 7.75, 12.67). Overall, AMI cases were also more likely to be hospitalized subsequently than the hospitalized controls (referent; adjusted odds ratio (AOR) = 1.47, 95%CI = 1.17, 1,85), although in the stratified analysis this association held for men (AOR = 1.73, 95%CI = 1.25, 2.41) but not for women (AOR = 1.25, 95%CI = .90, 1.73). Among those subsequently hospitalized, both women and men AMI cases consumed more hospital resources than the hospitalized controls, and there were gender differences suggesting that the effects on total charges and length of stay were greater for women than for men with AMI. Finally, although the AMI cases had greater adjusted mean increases in the number of instrumental activities of daily living limitations and lower body limitations than the nonhospitalized controls, they were no worse off than the hospitalized controls, and there were no gender differences in those effects. CONCLUSION: Relative to the appropriate comparison groups, hospitalization for an AMI increases the risk of death and the total costs and lengths of stay of subsequent hospitalizations for women more than for men. Therefore, increased primary prevention, diagnosis, and treatment efforts should be directed toward women. J Am Geriatr Soc 47:151–158, 1999.
Comparing Sexuality Communication Among Offspring of Teen Parents and Adult Parents: a Different Role for Extended Family

This brief report examined teenagers' sexuality communication with their parents and extended families. It compared who teens of early parents (those who had children when they were adolescents) and teens of later parents (those who were adults when they had children) talk to about sex. Eighth grade students (N=1281) in 24 schools completed survey items about their communication about sex. Structural equation modeling was used to predict communication profiles, while adjusting for the nesting of students within schools. After controlling for teens' age, gender, race/ethnicity, grades, parent/guardian closeness, and social desirability of survey responses, as well as family status and median family income, results showed that teens of early (teen) parents were more likely than teens of later (adult) parents to talk with both parents and extended family about sex and less likely than later parents to talk only with parents. These findings indicate that realities of teen sexuality communication for teens of early parents may extend beyond a parent-teen model to include extended family. Extended family involvement in educational outreach is a potential untapped resource to support sexual health for teens of early parents.
Risk Factor Intervention for Health Maintenance

Risk factors for disease consist of (i) personal habits, such as cigarette smoking and excessive alcohol consumption, and (ii) bodily characteristics, such as hypertension and high serum cholesterol. Progress in identifying and quantifying risk factors is opening the way to the prevention of disease and maintenance of health. Systematic, controlled trials of intervention against risk factors are beginning to produce evidence on the extent of success in reducing both the factors and the mortality from associated diseases.
Ontogenetic patterns in prey use by pallid sturgeon in the Missouri River, South Dakota and Nebraska

Summary The pallid sturgeon (Scaphirhynchus albus) is an endangered species native to the Missouri and Mississippi rivers. To date, recovery efforts have focused on stocking juvenile fish, but little is known about ontogenetic changes in diet composition. Although diet composition for pallid sturgeon is believed to change from macroinvertebrates to fish, it is unclear at what size and/or age these ontogenetic diet shifts occur. To evaluate diet composition, 29 hatchery-stocked pallid sturgeon (range 356–720 mm fork length [FL]; mean = 549; SE = 23) were collected from the Missouri River downstream of Fort Randall Dam, South Dakota and Nebraska during summer 2006. The majority of pallid sturgeon (72%) were captured within a large delta region formed by the Niobrara River in the headwaters of Lewis and Clark Lake. Predominant prey of pallid sturgeon based on percent occurrence was Ceratopogonidae (81%), Isonychiidae (67%), Chironomidae (52%), and fishes (24%). Percent composition by wet weight showed that diets were composed of fishes (68%), Ephemeroptera (23%), Decapoda (6%), and Diptera (3%). Graphical analysis of combined data showed that mayflies, particularly Isonychiidae, were an important component of pallid sturgeon diets. Nonetheless, the percent composition of fishes in the diet increased with pallid sturgeon body size; for fish > 600 mm FL (5–7 years of age) diets were composed primarily of fish prey (66%, mostly johnny darters Etheostoma nigrum). These findings highlight the importance of ontogenetic changes in diet composition for pallid sturgeon. Moreover, the unique habitat formed in the delta region is characterized by higher fish and invertebrate densities that may enhance foraging opportunities and thus improve recovery efforts for stocked pallid sturgeon.
Adolescent alcohol use and adult alcohol disorders: A two-part random-effects model with diagnostic outcomes

Alcohol use is often analyzed by treating the behavior as a single dimension, such as focusing on frequency of use. Based on data from a longitudinal study, this report considers two distinct aspects of semi-continuous alcohol use data. A two-part random-effects model was used to evaluate change in the log-odds and frequency of use from about age 13 to about age 18 years. Change features were then related to the log-odds of later alcohol disorders. Results suggested differences in the two aspects of use over time and their relationships with later disorders. Most important for the purposes of this study, different methods of analyzing antecedents and consequences of alcohol use trajectories were shown to generate both similar and disparate findings.
Development of the baroreflex in the young rat.

The baroreceptor-heart period reflex was assessed in conscious, freely behaving rat pups on postnatal days 6 and 14. The baroreceptor-heart period reflex was elicited using the α1-adrenergic agonist phenylephrine to increase blood pressure and the vasodilator, sodium nitroprusside, to decrease blood pressure. The autonomic effects of the baroreceptor manipulations were determined using pharmacological autonomic blockade. The data demonstrate that vasoconstriction produces a potent baroreflex-mediated bradycardia as early as postnatal day 6, which had previously been demonstrated only in anesthetized pups. In the anesthetized pup, the bradycardia is mediated by vagal activation, while we demonstrate that both vagal activation and sympathetic withdrawal occur in unanesthetized animals. In addition, the results replicate previous findings in rats demonstrating minimal cardiac sympathetic activation or vagal withdrawal following vasodilation during the first week of life, but substantial baroreflex-mediated tachycardia by the second week.
Hereditary neuropathy and vocal cord paralysis in a man with childhood diphtheria.

We present the case of a 37-year-old Afghani man with a history of childhood diphtheria, who was diagnosed with bilateral vocal cord paralysis at age 15 years. At about this time he developed progressive muscular wasting and distally predominant weakness, and subsequently developed respiratory insufficiency, necessitating nocturnal ventilatory support. His examination suggested a distal symmetric sensorimotor neuropathy, and his brother was similarly affected, although to a lesser degree. Electromyography (EMG) and nerve conduction studies revealed this process to be purely axonal. A diagnosis of possible hereditary motor and sensory neuropathy (HMSN) type IIc, hereditary axonal polyneuropathy with vocal cord paralysis, is proposed, although the question of early diphtheritic involvement of the vocal cords and peripheral nerves is also considered. © 2000 John Wiley & Sons, Inc. Muscle Nerve 23: 132–137, 2000
Effect of timing of cutting on patterning and proportion regulation during regeneration of the planarian Dugesia tigrina

The time interval between cuts that are made to obtain a tissue fragment from a planarian was found to be important to the process of its regeneration. Short fragments made by two transverse cuts across the body were more likely to regenerate abnormally when the interval between the two cuts was 5 or 12 min than when it was 1.5 min. The longer intervals specifically altered the regression line in the correlation between the length:width ratio of fragments and frequency of abnormal regenerates. This effect occured regardless of which region of the body the fragment was taken from. The time interval also affected body proportioning in regenerates and to the greatest degree in fragments derived from the region located immediately behind the head. These results indicate that events occuring shortly after a cut is made in a planarian significantly affect structure patterning and proportioning of the regenerate.
Peroxiredoxins as Molecular Triage Agents, Sacrificing Themselves to Enhance Cell Survival During a Peroxide Attack

In this issue of Molecular Cell, Day et al. (2012) reveal a surprising benefit of peroxiredoxin inactivation at high H2O2, showing that in Schizosaccharomyces pombe turning off peroxide defenses preserves the pool of reduced thioredoxin for repairing proteins vital to survival.
Retrieval and analysis of a clinical total artificial heart

Examination by light microscopy, scanning electron microscopy (SEM), and x-ray microanalysis of a clinical total artificial heart (TAH) implanted for 112 days revealed no evidence of calcification, pannus, or vegetative thrombus. A macroscopic thrombus was seen along the suture line in the right atrium but did not obstruct blood flow or valve function. Microscopic thrombi (less than 0.1 mm) and evidence of microemboli were observed on the pumping diaphragm using SEM. Characterization of selected polyetherurethane (PEU) samples from the pumping bladders and housing by Curie-point pyrolysis mass spectrometry (Py-MS) revealed unexpected differences between postmortem retrieved ventricles. Although the origin of these differences could be traced back to batch-to-batch variations in the original PEU material (Biomer), the precise nature of the observed differences in chemical structure and/or composition is still unknown. Numerical comparison between pyrolysis mass spectra from PEU samples exposed to blood or tissue and unexposed samples from the same ventricles did not detect evidence of biodegradation. Continual improvements in fabrication and quality control should minimize surface imperfections and ensure polymer reproducibility; however, existing materials and design parameters appear to be adequate for continued clinical implantation.
Fabricating Low‐Fusing Metal Casts for More Accurate Implant Prosthodontics

An important factor that affects the clinical success of dental implants is the way stresses are transferred to the bone via the implant framework and fixture. An ill-fitting implant framework will contribute to these stresses and may result in catastrophic failure of the prosthesis or one of the components and/or fixtures, in addition to possible alveolar bone loss. Many factors may contribute to the difficulty of achieving a passive fit on a complete-arch implant framework. A technique for producing an accurate master cast by using a low-fusing metal is described. The low-fusing metal is dimensionally more accurate than conventional gypsum products. The technique does not require a significant change from conventional chairside and laboratory procedures for complete-arch master cast impressions, and should result in a more passively fitting framework.
Clinical status of at-risk individuals 5 years later: further validation of the psychometric high-risk strategy.

The authors hypothesized that at-risk individuals identified on the basis of their Chapman scale scores would be diagnosed with schizophrenia-spectrum disorders at follow-up. In the present study, the authors interviewed 135 young adults approximately 5 years following their initial assessment. The at-risk groups included high scorers on the Perceptual Aberration and/or Magical Ideation Scales (n = 59) and high scorers on the revised Social Anhedonia Scale (n = 32). The control participants (n = 44) scored below 0.5 SD of the same-sex group means on all the scales. At the follow-up, the groups differed in terms of their likelihood of having a schizophrenia-spectrum diagnosis, X 2 (2) = 9.79, p <.01. The at-risk groups reported more frequent and severe psychotic-like experiences relative to the control group. These findings support the predictive validity of the Chapman psychosis-proneness scales and may enhance the power of early detection efforts.
CD14 : a candidate biomarker for the prognosis of polycystic kidney disease

Zhou et al. validate the expression of markers of the innate immune system in the cpk mouse model of polycystic kidney disease (PKD), in human recessive PKD, and in human autosomal dominant PKD and show that CD14 expression correlates with PKD progression, even from very early stages of disease. Moreover, they show that CD14 is expressed from the renal tubule epithelial cells, suggesting a mechanism of Toll-like receptor-4 activation in PKD prior to the infiltration of inflammatory cells.
Nitrogenase from Clostridium pasteurianum. Changes in optical absorption spectra during electron transfer and effects of ATP, inhibitors and alternative substrates.

The iron protein of nitrogenase (Fe protein) was oxidized without inactivation in a system containing Mg · ATP and a low level of the molybdenum-iron protein of nitrogenase (Mo-Fe protein), and the optical absorption spectra of oxidized and reduced Fe protein were recorded. Oxidation increased the absorbance with the appearance of a peak at 375 nm; the spectra resembled those of bacterial type ferredoxins. A kinetic study showed that the Fe protein was oxidised at a rate that was of the same magnitude as the steady-state rate of electron transfer. The kinetics of ATP utilization in the nitrogenase reaction was studied with the continuous assay for dithionite oxidation. No deviation from Michaelis-Menten kinetics was found; the Michaelis constant for Mg · ATP was 0.18 mM. ADP inhibited dithionite oxidation and induced deviations from the Michaelis Menten equation. Cyanide and azide inhibited dithionite oxidation, whereas rates of dithionite oxidation under N2, Ar or H2 were identical. The Fe protein was inactivated and bleached by cyanide.
What Went Wrong in New Orleans? An Examination of the Welfare Dependency Explanation

The impact of Hurricane Katrina was especially dramatic in New Orleans, where catastrophic flooding threatened the lives of thousands of residents who did not or could not evacuate before the storm. To explain the large number of residents who did not evacuate in time, some commentators blame a lack of government aid and assistance for the poor while others fault an excessive dependence of the poor on government. Welfare dependency theorists, in particular, contend that a dependency-induced “mentality of helplessness” was prevalent among New Orleans' poor and helps to account for the incomplete evacuation. To gauge the plausibility of this argument, I use data from a unique survey to examine the characteristics of New Orleanians who were trapped in the flooded city. The findings indicate that, contrary to the expectations of welfare dependency theorists, more than half of the New Orleanians in question were employed full time before the storm and most displayed initiative after the disaster. Furthermore, in multivariate analyses, characteristics highlighted by dependency theorists did not predict the odds of pre-storm evacuation. Other explanations for the incomplete evacuation are explored.
Characterization of an Endo-[beta]-1,4-Glucanase Gene Induced by Auxin in Elongating Pea Epicotyls

A gene (EGL1) encoding an endo-[beta]-1,4-D-glucanase (EGase, EC 3.2.1.4) of pea (Pisum sativum) has been cloned and characterized. EGL1 encodes a 486-amino acid polypeptide, including a 24-mer putative signal peptide. The mature protein has a calculated molecular mass of 51.3 kD and an isoelectric point of 9.1. This pea EGase shares significant similarity with EGases from other plant species, but it appears to be distinct from the EGases associated with abscission and fruit ripening. Although EGL1 transcripts are detected in all parts of pea plants, they are relatively abundant in flowers and young pods undergoing rapid growth and most abundant in elongating epicotyls of etiolated seedlings. When epicotyl segments (6 mm long, 4 mm from the apical hook) are incubated in a 5 [mu]M solution of the synthetic auxin analog 2,4-dichlorophenoxyacetic acid, the concentration of EGL1 mRNA increases about 10-fold when the segments elongate most rapidly.