cssi/SciSciGPT-SciSciNet huggingface dataset:
The Young and the Reckless: Adolescent Reckless Behavior

In Rio de Janeiro in Brazil, they "surf" on the tops of trains, standing with arms outstretched as the trains rush along. The surfers—adolescents, girls as well as boys—are undeterred by the death of 150 fellow surfers per year and the injury of 400 more, from falling off trains or from hitting the 3,000-volt electric cable that runs above. On Truk Island in the South Pacific, drunkenness, fighting, and sexual experiences with a variety of lovers are all part of typical development for young men in their late teens and early 20s. They also go spearfishing where large sharks are common, and seek out other "daredevil risks with life and limb."^ In urban New Jersey in the United States, adolescent boys steal automobiles, then drive them wildly for a few hours before crashing or abandoning them. Why do many adolescents seek out experiences that involve physical, psychological, or legal risks? What blend of developmental and socialization factors leads to reckless behavior among adolescents? Researchers and theorists have offered a number of explanations, focusing on such behavior as driving an automobile at high speeds or while intoxicated, having sex without conJeffrey Arnett is Associate Professor of Human Development and Family Studies at the University of Missouri-Columbia. His research interests include adolescent reckless behavior, socialization, adolescents' uses of media, and the transition from adolescence to young adulthood. Address correspondence to Jeffrey Arnett, Department of Human Development and Family Studies, 31 Stanley Hall, Columbia, MO 65211. traception or with someone not known well, using illegal drugs, and committing crimes. Richard Jessor, for example, has suggested that the developmental motivation for such behavior is the desire of adolescents to achieve adult status.^ His theory also includes personality characteristics (such as self-esteem and value placed on achievement), family environment, and religiosity. Charles Irwin, Jr., presents a model that emphasizes pubertal timing and its effects on risk perception and peergroup association.^ My own focus is on three developmental predispositions for reckless behavior in adolescence—sensation seeking, egocentrism, and aggressiveness—and their interaction with the cultural socialization environment.
Seasonal Variation of Stored Wheat Environment and Insect Populations

Temperatures of wheat in the top meter in on-farm cylindrical metal bins in Kansas were uniform and within a favorable range of 27–34°C for the first 12 wk and then declined at rates ranging from 1.3 to 2°C/wk. Cooling of grain from the outside and surface inward and downward resulted in temperature gradients. Grain moisture in the top 0.5 m declined during the first 12 wk and then increased to levels well above initial moisture. Elsewhere in the top meter, wheat retained its initial moisture level except for the tendency of grain near the bin wall to be drier. Population growth rate of the dominant species, Cryptolestes ferrugineus (Stephens), declined over the wheat storage period in the top meter of grain as a result of first the parasite Cephalonomia waterstoni Gahan and then falling temperatures. C. ferrugineus adults showed only a slight tendency to move toward the warmer or moister parts of the bin. Trogoderma glahrum (Herbst) adults and larvae and Trogoderma inclusum LeConte adults, the next most abundant species, were found mainly near the bin wall. Rhyzopertha dominica (F.) were first detected after 12 wk and were found only in the center.
Abstract 4645: Plasma cytokine and angiogenic factor (CAF) profiling for identification of markers associated with clinical benefit from bevacizumab (BEV) and with primary tumor presence in a phase II presurgical study of metastatic renal cell carcinoma (mRCC) patients

Purpose: The main objectives of this exploratory analysis were to identify biomarkers in blood associated with clinical benefit from bevacizumab, and to assess CAF changes related to nephrectomy (Nx) in mRCC. Methods: Plasma samples were obtained from 44 pts participating in a frontline presurgical study of bevacizumab in clear cell mRCC (22 pts treated with BEV and 22 pts with BEV and erlotinib) (Jonasch et al. J Clin Oncol 2009), before treatment (BL), after 8 weeks of therapy/pre-nephrectomy (Nx), after 16 weeks of therapy/postNx, and every 4 weeks thereafter. Multiplex bead suspension arrays and ELISA were used to measure concentrations of 58 CAFs including VEGF, VEGF-C, placental growth factor (PlGF), soluble CAIX (sCA9), hepatocyte growth factor (HGF), osteopontin (OPN), matrix metalloproteinase-9 (MMP9), transforming growth factor (TGF)b1, endoglin, type IV collagen (ColIV), and multiple chemokines and interleukins (IL). CAFs were correlated with progression-free survival (PFS), overall survival (OS), and best response in primary and metastatic disease (% relative to BL). Results: Of 58 CAFs available at BL, high (above median) concentrations of TRAIL and ColIV were associated with longer PFS (7.6 v 2.8 and 8.1 v 2.9 months [mos], respectively; both P=0.001) and OS (27.9 v 13.2 and 32.8 v 14.3 mos, respectively; P=0.023 and P=0.025). In addition to high TRAIL, low levels of VEGF and PlGF also showed a significant association with enhanced response both in primary disease and metastases (all P Conclusions: We identified TRAIL, ColIV, VEGF and PlGF as candidate CAFs associated with clinical benefit from BEV in clear cell mRCC. The combination of BEV with erlotinib resulted in distinct on treatment CAF changes. The integration of these data with CAF profiling studies in pts with non-metastatic RCC could help define CAF sets useful to assist in risk stratification of RCC pts and provide insights into the biology of RCC progression. Citation Format: Alper Yetil, Eric Jonasch, Xuemei Wang, Christopher Wood, Surena Matin, Hai T. Tran, Nizar M. Tannir, John V. Heymach, Amado J. Zurita. Plasma cytokine and angiogenic factor (CAF) profiling for identification of markers associated with clinical benefit from bevacizumab (BEV) and with primary tumor presence in a phase II presurgical study of metastatic renal cell carcinoma (mRCC) patients [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4645. doi:10.1158/1538-7445.AM2013-4645
Abnormal pressure natriuresis. A cause or a consequence of hypertension

In all forms of chronic hypertension, the renal-pressure natriuresis mechanism is abnormal because sodium excretion is the same as in normotension despite the increased blood pressure. However, the importance of this resetting of pressure natriuresis as a cause of hypertension is controversial. Theoretically, a resetting of pressure natriuresis could necessitate increased blood pressure to maintain sodium balance or it could occur secondarily to hypertension. Recent studies indicate that, in several models of experimental hypertension (including angiotensin II, aldosterone, adrenocorticotrophic hormone, and norepinephrine hypertension), a primary shift of renal-pressure natriuresis necessitates increased arterial pressure to maintain sodium and water balance. In genetic animal models of hypertension, there also appears to be a resetting of pressure natriuresis before the development of hypertension. Likewise, essential hypertensive patients exhibit abnormal pressure natriuresis, although the precise cause of this defect is not clear. It is likely that multiple renal defects contribute to resetting of pressure natriuresis in essential hypertensive patients. With long-standing hypertension, pathological changes that occur secondary to hypertension must also be considered. By analyzing the characteristics of pressure natriuresis in hypertensive patients and by comparing these curves to those observed in various forms of experimental hypertension of known origin, it is possible to gain insight into the etiology of this disease.
Effects of Harvest Time, Holding Condition, and Time of Holding on Prepackaging Loss and Storage Quality of ‘Tifblue’ Rabbiteye Blueberries

ABSTRACT Tifblue rabbiteye blueberries {Vacciniwn ashei, Reade) were harvested twice daily (09:00, 14:30) and held under one of two conditions (cooled room, outside in shade) for six holding times (0, 1.5, 3, 6, 12, 24 hours after harvest) before refrigeration. Blueberries rejected when sorted were affected by harvest time (more rejected from 14:30 harvest), holding condition (more rejected from shade treatments) and holding time (more rejected as holding time increased). Storage defects after 21 days at 4.4°C (40°F) were affected by holding time (% defects increased with holding time). Treatments were intended to simulate the conditions of a small grower with limited facilities.
Milieu management of traumatized youngsters.

TOPIC. Traumatized youngsters are disproportionately represented in out-of-home treatment facilities. Conceptual models that guide treatment of traumatized youngsters are not well integrated with models that guide milieu management. PURPOSE. To describe a milieu management approach for treatment of traumatized youngsters. somas. Clinical experience with hospital and residential treatment facilities and therapeutic foster homes, as well as literature support. CONCLUSIONS. Familiar treatment strategies take on an additional meaning when they are implemented in the context of the children's histories of exposure to traumatic euents.
Pyridine-Substituted Oligopeptides as Scaffolds for the Assembly of Multimetallic Complexes: Variation of Chain Length

This paper presents the synthesis and characterization of pyridine-substituted artificial oligopeptides with an aminoethylglycine backbone of varying length, which are designed to act as scaffolds for the self-assembly of multimetallic structures. The identities and purities of the oligopeptides are confirmed with mass spectrometry, (1)H NMR, HPLC, and pH titrations. The acid dissociation constants for the oligopeptides were determined and were found to decrease with increasing pyridine units. Titrations of the oligopeptides with Cu(II) and Pt(II) complexes containing the tridentate ligands 2,2':6',2''-terpyridine and pyridine 2,6-dicarboxylic acid were monitored using UV-visible absorption spectroscopy and showed stoichiometric binding based on the number of pyridines on the peptide strand. Metal titrations performed using an analogous oligopeptide with methyl substituents (in place of the pyridine ligands) showed very weak or no binding. In the case of the oligopeptides containing bound Pt(terpyridine)(2+) complexes, cyclic voltammetry reveals two sequential one-electron reductions at formal potentials that do not vary as a function of oligopeptide length. The measured diffusion coefficients were measured with chronoamperometry and were found to decrease with increasing oliopeptide length.
Spinal Cord Injuries Containing Asymmetrical Damage in the Ventrolateral Funiculus Is Associated With a Higher Incidence of At-Level Allodynia

Approximately 70% of male rats receiving severe T8 spinal contusions develop allodynia in T5-7 dermatomes (at-level) beginning two weeks post-injury. In contrast, rats having either complete transections or dorsal hemisections do not develop allodynia at-level following chronic spinal cord injury (SCI). In the present study, incomplete laceration and contusion injuries were made to test for neuroanatomical correlates between areas of white matter damage/sparing at the lesion epicenter and the presence/absence of allodynia. Following incomplete laceration lesions and six weeks of behavioral testing, histological reconstruction and analysis of the lesion epicenters revealed a significant difference (p<.001) in the amount of ventrolateral funiculus (VLF) asymmetry between rats showing pain-like responses evoked by touch (74.5% ± 8.4% side-to-side difference in VLF damage) versus those not responding to touch (11.3% ± 4.4% side-to-side difference in VLF damage). A five week mean allodynia score for each rat that incorporates a full range of forces that are all innocuous in intact controls revealed that the degree of hypersensitivity at level is related to the extent of VLF asymmetry post-SCI. No other damaged spinal white matter or gray matter area was correlated with sensitivity to touch. Similar findings were obtained for rats receiving T8 contusions, a more clinically relevant injury. These data suggest that different extents of damage/sparing between the two sides of VLF are likely a requisite for the development of allodynia after SCI.
Structural Redundancy and Multiplicity within Networks of US Corporate Directors

The argument of this paper is that social ties beyond the boardroom matter. At the structural level, social ties from non-profit foundations, cultural organizations, university boards, policy planning organizations, and private social clubs add unique ties to those established by interlocking directorates. In addition, the multiple configurations of these social affiliations increase the centrality and reduce the social distance among the corporate directors. Although visualizations of these social networks underscore the changing roles these extra-corporate ties play in uniting corporate directors, they cannot precisely capture the unique effects of ties created by social affiliations outside the boardroom. Utilizing the concepts of structural redundancy and multiplicity, the paper describes the unique contribution each set of ties makes in constructing the social mosaic of corporate America during the second half of the 20th century. The results indicate a dramatic reduction in the role private clubs pl...
Adolescent perceptions of friendship and their associations with individual adjustment

This study of 282 dyads examines early- and mid-adolescents' perceptions of friendship quality and their association with daily disagreements, self- and mother reports of behaviour problems, and school grades. Actor and partner analyses identify unique associations between perceptions of friendship quality and perceptions of daily conflict. Actor effects reveal links between friendship negativity and self-perceptions of conflict affective intensity, relationship impact, post-conflict interaction, and post-conflict separation, and between friendship positivity and self-perceptions of relationship impact. Partner effects reveal links between friendship negativity and partner perceptions of conflict outcomes. Perceptions of relationship quality were also associated with self- and mother reports of behaviour problems and with school grades, such that individual and dyadic views of friendship negativity were linked to detrimental outcomes. The worst outcomes tended to be reserved for dyads in which one or both friends reported high levels of relationship negativity.
Effects of Hurricane Floyd Inland Flooding, September-October 1999, on Tributaries to Pamlico Sound, North Carolina

Hurricane Floyd in September 1999 caused disastrous flooding from South Carolina to Massachusetts in the United States, with particularly severe and prolonged flooding in eastern North Carolina resulting in record flood- flow loadings of freshwater and contaminants to Pamlico Sound, North Carolina. The inland flooding, water quality, and loadings to Pamlico Sound were determined as part of a multi-agency response to the floods and in an effort to under- stand the effects of the floods on the greater Pamlico Sound Basin. All major river basins draining to Pamlico Sound experienced floods at the 500-yr recurrence level. The volume of flood waters entering Pamlico Sound during September- October 1999 was estimated to be equivalent to about 95% of the volume of Pamlico Sound, meaning that flood waters could have essentially displaced most of the water present in Pamlico Sound. Nitrogen and phosphorus loads to the Pamlico River estuary and Neuse River estuary, the two principal estuaries draining to Pamlico Sound, in a 36-d period during the flooding were between 50-90% of the long term average annual loads. Pesticide concentrations in flood waters were surprisingly high, given the amount of dilution produced by the floodwaters.
Gravitino dark matter from Q-ball decays

Affleck-Dine baryogenesis, accompanied by the formation and subsequent decay of $Q$-balls, can generate both the baryon asymmetry of the Universe and dark matter in the form of gravitinos. The gravitinos from $Q$-ball decay dominate over the thermally produced population if the reheat temperature ${T}_{R}\ensuremath{\lesssim}{10}^{7}\text{ }\text{ }\mathrm{GeV}$. We show that a gravitino with mass $\ensuremath{\sim}1\text{ }\text{ }\mathrm{GeV}$ is consistent with all observational bounds and can explain the baryon-to-dark-matter ratio in the gauge-mediated models of supersymmetry breaking for a wide range of cosmological and $Q$-ball parameters. Moreover, decaying $Q$-balls can be the dominant production mechanism for ${m}_{3/2}l1\text{ }\text{ }\mathrm{GeV}$ gravitinos if the $Q$-balls are formed from a $(B\ensuremath{-}L)=0$ condensate, which produces no net baryon asymmetry. Gravitinos with masses in the range $50\text{ }\text{ }\mathrm{eV}\ensuremath{\lesssim}{m}_{3/2}\ensuremath{\lesssim}100\text{ }\text{ }\mathrm{keV}$ produced in this way can act as warm dark matter and can have observable imprint on the small-scale structure.
Case processing in the Harris county, Texas criminal justice system: A comparison across crime types

This study tested the hypothesis that when the criminal justice system is working under a “limited capacity to punish,” the processing of some types of crimes might be emphasized over the processing of other types. This hypothesis was tested through a comparison of the processing of sexual assault cases with the processing of robbery and aggravated assault over the period 1980–1988 in Harris County, Texas. Prison use was found to increase for aggravated assault and for sexual assault of both children and adults while for robbery the use of prison decreased slightly. Jail usage increased for aggravated assault and robbery while it decreased for sexual assault cases. Prison sentence lengths also tended to increase except for cases of aggravated assault. These trends seem to suggest that sexual assault cases are not dismissed during times of a limited capacity to punish. However, there was some evidence that at earlier points of processing there was a reluctance to prosecute cases of sexual assault of an adult. Thus, it is premature to conclude that in times of a limited capacity to punish, the prosecution of violent crimes committed against women might be deemphasized to make space for cases more likely to end in conviction. Rather, criminal case processing includes more complexities than can be captured simply through an examination of the likelihood of conviction.
An efficient synthesis of [1,1]ferrocenophane via 1,1′-bis(6-fulvenyl)ferrocene

Abstract [1,1]Ferrocenophane can be prepared by reduction of 1,1′-bis(6-fulvenyl)ferrocene with complex borohydrides to give the dianion of 1,1′-bis(cyclopentadienylmethyl)ferrocene. Reaction of this dianion with ferrous chloride produces the ferrocenophane in good yield.
Attention deficit disorder and methylphenidate: normalization rates, clinical effectiveness, and response prediction in 76 children.

ABSTRACT Objective To evaluate the magnitude and clinical significance of methylphenidate (MPH) effects on the classroom behavior and academic performance of 76 children with attention deficit disorder/hyperactivity (ADDH). Method A double-blind, placebo controlled, within-subject (crossover) experimental design was used to evaluate acute MPH effects at four dose levels (5 mg, 10 mg, 15 mg, and 20 mg) on children's attention, academic functioning, and behavior in regular classroom settings. Results were contrasted with a normal control sample. Results Standard statistical analysis revealed MPH effects on classroom functioning that were primarily linear. Analysis of the clinical significance of effects indicated that large proportions of treated children exhibited significantly improved or normalized classroom functioning; however, a large subset of them failed to show improved academic functioning. Overall, children failing to respond at lower dose levels have a high probability of improving or becoming normalized as a function of increasing dose. Conclusions For a majority of children with ADDH, MPH results in significantly improved or normalized attention and classroom behavior. A significant subset, however, fail to realize gains in their academic functioning and will require supplemental interventions.
Real-time control of a nonlinear electromagnetic actuator

Abstract This paper describes theoretical and experimental investigations aimed at controlling the trajectory of a nonlinear, clapper-type electromagnetic actuator. The vehicle for the investigations is the three-piece actuator used in the IBM 4248 impact line printer. The control algorithm seeks to regulate flight time—the time required for the actuator to move from its rest position to its point of impact—by modulating the pulse width delivered to the coil as a function of one measurement of position and velocity. The actuator is modelled mathematically, and a control law based on initial conditions is numerically derived. A similar control law based on mid-flight conditions is derived experimentally, by computer-controlled adaptation, and its ability to regulate flight time is demonstrated.
Measuring Corporate Reputation Definition and Data

By examining existing definitions and data sets, this article explores the current state of efforts intended to measure corporate reputation. Both definitions and data are found to be lacking, and it is argued that many deficiencies in definition and data can be attributed to the fact that theory development related to corporate reputation has been insufficient.
A missing link in the transformation from asymmetric to symmetric metallofullerene cages implies a top-down fullerene formation mechanism

An asymmetric pentalene-containing C1(51383)-C84 fullerene cage is found in two different metal carbide metallofullerenes. This particular cage can, in simple steps, rearrange into many well-known fullerene cages that are more stable and more symmetric, suggesting it is likely that metallofullerenes are generated by a ‘top-down’ formation mechanism.
Radioimmunoassay of bovine neurophysin: specificity of neurophysin I and neurophysin II.

Abstract The pituitary binding proteins of oxytocin and vasopressin were isolated from acetone dried bovine posterior pituitary glands. The two electrophoretically distinct binding proteins, neurophysin I and neurophysin II, were shown to be immunologically distinct. A radioimmunoassay for each was developed capable of measuring 0.02 ng in the assay mixture with minimal cross-reaction between neurophysin I and neurophysin II. These binding proteins constitute 20% of the acid extractable protein of fresh bovine posterior pituitary and 0.8% of acid extractable protein of the hypothalamus. Small amounts of neurophysin antigen were found in the anterior pituitary, muscle and the kidney, but not in other organs. Neurophysin was detected in unextracted bovine plasma. There is little cross-reaction of these neurophysins with pituitary extracts of other species. The use of zirconyl phosphate gel to separate free and bound antigen in the radioimmunoassay is described.
Overqualified Minority Youth in a Detroit Job Training Program: Implications for the Spatial and Skills Mismatch Debates

This article explores an unanticipated finding from my research study, “Suburban Job Search of Urban Workers,” which I implemented to study barriers to suburban job search as perceived by young Black and White workers in Detroit. Of 55 African American respondents, 33 (60%) had either been accepted to or attended college and may have been overqualified for the training programs they were in. Likely explanations for respondents’ choices include lack of networks, poor self-esteem, perceived financial issues, and the lure of jobs in the Big 3 firms in the context of an overarching “explanation”: the extreme and stark segregation that characterizes the Detroit metropolitan area. I believe that this entrenched segregation has both narrowed the information pipeline and increased the notion of “hostile suburbs” among Black urban youth. This perceived hostility is borne out by described discriminatory experiences and may have increased young people’s apprehension when seeking jobs and educational opportunities be...
Variation support for end users

End-user programming environments provide central repositories where users can execute and store their programs. However, these environments do not provide facilities by which users can keep track of the variations that they create for their programs. In the professional world, software developers use variation management for code reuse, program understanding, change traceability, debugging and maintenance.
Models of multivinyl free radical photopolymerization kinetics

Models for predicting multivinyl free radical photopolymerization that incorporate diffusion controlled propagation and termination are discussed. One model focuses on spatial effects by incorporating heat and mass transfer in photopolymerizing films. Temperature, species concentrations, e.g., oxygen and initiator, and light intensity are varied as a function of both time and depth. Specifically, the effect of using polychromatic initiation on oxygen inhibition was investigated. The model predicts that by utilizing initiating radiation of two distinct wavelengths, it is possible to overcome oxygen inhibition and achieve complete cure. The second model incorporates chain length dependent termination (CLDT) and chain transfer to polymer (CTP) in a homogenous, polymerizing system. Specifically, how CTP affects the polymerization rate (Rp), the reaction diffusion coefficient, the scaling relationship between polymerization rate and initiation rate ( Ri), i.e., Rp ∝ R α , and the transition from CLDT to reaction diffusion controlled termination was investigated. The model predicts that, in general, at low double bond conversion, CTP inclusion decreases the reaction diffusion coefficient and increases the polymerization rate. Additionally, increasing the CTP rate decreases the double bond conversion both at which the termination mechanism begins to transition from CLDT to reaction diffusion controlled termination and at which reaction diffusion controlled termination becomes the dominant termination mechanism. The model provides more insight into the termination mechanism and complex polymerization behavior. © 2003 Elsevier Science B.V. All rights reserved.
The Faces of the Gods: Vodou and Roman Catholicism in Haiti

Vodou, the folk religion of Haiti, is a by-product of the contact between Roman Catholicism and African and Amerindian traditional religions. In this book, Leslie Desmangles analyzes the mythology and rituals of Vodou, focusing particularly on the inclusion of West African and European elements in Vodouisants' beliefs and practices. Desmangles sees Vodou not simply as a grafting of European religious traditions onto African stock, but as a true creole phenomenon, born out of the oppressive conditions of slavery and the necessary adaptation of slaves to a New World environment. Desmangles uses Haitian history to explain this phenomenon, paying particular attention to the role of the seventeenth- and eighteenth-century maroon communities in preserving African traditions and the attempts by the Catholic, educated elite to suppress African-based "superstitions." The result is a society in which one religion, Catholicism, is visible and official; the other, Vodou, is unofficial and largely secretive. |Desmangles analyzes the mythology and rituals of Vodou, the folk religion of Haiti and a by-product of the contact between Roman Catholicism and African and Amerindian traditional religions. Focusing on the inclusion of West African and European elements in Vodouisants' beliefs and practices, Desmangles shows that Vodou is not merely a grafting of European religious traditions onto African stock, but a true creole phenomenon.
Names and Weapons.

Names given weapons structure the situations in which they are used. The essay traces the theoretical significance of names as titles for situations and applies the results to the United States’ ICBM programs. The names given ICBMs preserve their utility as weapons by linking them to the myths of the 19th‐century western frontier.
Ultra-wideband channel modeling for intravehicle environment

With its fine immunity to multipath fading, ultra-wideband (UWB) is considered to be a potential technique in constructing intravehicle wireless sensor networks. In the UWB literature, extensive measuring and modeling work have been done for indoor or outdoor propagation, but very few measurements were performed in intravehicle environments. This paper reports our effort in measuring and modeling the UWB propagation channel in commercial vehicle environment. In our experiment, channel sounding is performed in time domain for two environments. In one environment, the transmitting and the receiving antennas are put beneath the chassis. In another environment, both antennas are located inside the engine compartment. It is observed that paths arrive in clusters in the latter environment but such clustering phenomenon does not exist in the former case. Different multipath models are used to describe the two different propagation channels. For the engine compartment environment, we describe the multipath propagation with the classical S-V model. And for the chassis environment, the channel impulse response is just represented as the sum of multiple paths. Observation reveals that the power delay profile (PDP) in this environment does not start with a sharp maximum but has a rising edge. A modified S-V PDP model is used to account for this rising edge. Based on the analysis of the measured data, channel model parameters are extracted for both environments.
Software support for students engaging in scientific activity and scientific controversy

Computer environments could support students in engaging in cognitive activities that are essential to scientific practice and to the understanding of the nature of scientific knowledge, but that are difficult to manage in science classrooms. The authors describe a design for a computer-based environment to assist students in conducting dialectical activities of constructing, comparing, and evaluating arguments for competing scientific theories. Their choice of activities and their design respond to educators' and theorists' criticisms of current science curricula. They give detailed specifications of portions of the environment. © 1994 John Wiley & Sons, Inc.
Novel targets and therapeutic strategies for type 2 diabetes

The number of people diagnosed with type 2 diabetes mellitus (T2DM) is increasing at an alarming rate in western societies and has become a major health concern. During the past decade, studies using transgenic animals, gene transfer and pharmacological agents have yielded many data that have helped understand the molecular alterations characteristic of T2DM. This has opened the possibility for the development of potentially more-effective therapies, mainly focused on attenuating hepatic glucose production, enhancing glucose-dependent insulin secretion, enhancing the insulin signal transduction pathway, inhibiting lipolysis from the adipose tissue and promoting fatty acid oxidation.
A thermodynamic description of the Al-Mg-Zn system

A thermodynamic description of the Al-Mg-Zn system was developed based on critically evaluated experimental data. All binary intermetallic phases are assumed to have negligible ternary solubility except for MgZn2. Three different thermodynamic models are applied to three different types of phases in this system, i.e., disordered solution phases, stoichiometric compounds, and semistoichiometric phases. The model parameters are optimized based on the thermodynamic descriptions of the constituent binaries and experimental phase equilibrium and thermodynamic data available in the literature. The good agreement obtained between several calculated isopleths and thermodynamic values of the liquid phase and experimental data shows that the current description of this system is reasonable. The calculated phase equilibria in the Al-rich corner are believed to be reliable for practical applications, while those away from the Al-rich region are subjected to large uncertainty. Additional experimental investigations are needed to firmly establish the phase equilibrium of this system over wide ranges of composition and temperature.
Free transverse vibrations of uniform circular plates and membranes with eccentric holes

Abstract An analytical method, based on the transformation of cylindrical wave functions, is presented for calculating the free transverse vibrations of uniform circular plates and membranes with eccentric holes. The wave equations governing the small transverse motion of the plates and membranes are solved exactly to satisfy the boundary conditions at both inner and outer edges, and the associated frequency equations for the plates and membranes are derived. The analysis also includes the vibrations of uniform circular plates and membranes with concentric holes as special cases. Numerical examples are presented to show the dependence of the eigenfrequency on the eccentricity and on the ratio of the inner radius to outer radius. The main purpose of the paper is to illustrate that an exact, analytical solution of the vibrations of eccentric annular plates and membranes can be obtained.
Distance metrics for high dimensional nearest neighborhood recovery: Compression and normalization

Previous work has shown that the Minkowski-p distance metrics are unsuitable for clustering very high dimensional document data. We extend this work. We frame statistical theory on the relationships between the Euclidean, cosine, and correlation distance metrics in terms of item neighborhoods. We discuss the differences between the cosine and correlation distance metrics and illustrate our discussion with an example from collaborative filtering. We introduce a family of normalized Minkowski metrics and test their use on both document data and synthetic data generated from the uniform distribution. We describe a range of criteria for testing neighborhood homogeneity relative to underlying latent classes. We discuss how these criteria are explicitly and implicitly linked to classification performance. By testing both normalized and non-normalized Minkowski-p metrics for multiple values of p, we separate out distance compression effects from normalization effects. For multi-class classification problems, we believe that distance compression on high dimensional data aids classification and data analysis. For document data, we find that the cosine (and normalized Euclidean), correlation, and proportioned city block metrics give strong neighborhood recovery. The proportioned city block metric gives particularly good results for nearest neighbors recovery and should be used when utilizing document data analysis techniques for which nearest neighborhood recovery is important. For data generated from the uniform distribution, neighborhood recovery improves as the value of p increases.
Aberrant signaling pathways in meningiomas

In this article, we provide a brief description of the current understanding of aberrant signaling pathways in meningiomas. Cell signaling pathways are responsible for cellular differentiation, development, growth, growth inhibition, and death. In fact, signaling pathways can affect multiple intracellular functions, including those responsible for development, angiogenesis, and apoptosis. Ultimately, a further understanding of the signaling pathways involved in meningioma tumorigenesis will lead to the development and application of novel molecular treatments, such as small molecule inhibitors or interfering ribonucleic acid technologies.
Accelerated clearcoat weathering studied by dynamic mechanical analysis

Abstract Automotive basecoat/clearcoat (BC/CC) systems of the acrylic polyol/melamine formaldehyde (ACR/MF) type were analyzed by dynamic mechanical analysis (DMA) before and after exposure to QUV. DMA changes after 500 h exposure were compared to gloss retention after five year Florida exposure or 2500 h QUV exposure. DMA readily distinguished between ‘poorer’ and ‘better’ BC/CC films received in a blind study. Crosslink density and T g both increased during QUV. DMA changes depended strongly on the presence or absence of hindered amine light stabilizer (HALS). Variations in the basecoats had only minor effects on DMA results. Poly(urethane) clearcoats (without basecoats) were also studied. Differences in weathering behavior of films prepared with three widely used poly(isocyanates) are reported. Crosslink density decreased and T g increased during QUV exposure. Stabilizers were very effective in the poly(urethane) clearcoats. DMA results are discussed in relation to FT-IR spectra obtained before and after QUV.
Preparation and characterization of atomically clean, stoichiometric surfaces of n- and p-type GaN(0001)

It is demonstrated that in situ exposure of the (0001) surface of n- and p-type GaN thin films to flowing ammonia at 860 °C and 10−4 Torr removes hydrocarbon and oxygen/hydroxide species below the detectable limits of x-ray and ultraviolet photoelectron spectroscopies (UPS) and decreases the Ga/N ratio from 1.3 to 1.0. Additional indications of the efficacy of this ammonia-based chemical vapor cleaning (CVC) process were the shifts in the Ga 3d and the N 1s core level positions from the as-loaded to the CVC surfaces of the n-type samples from 21.0±0.1 to 20.6±0.1 eV and from 398.3±0.1 to 398.0±0.1 eV, respectively, and the change in the UPS measured low energy spectrum turn on from 3.9±0.1 (as-loaded samples) to 3.0±0.1 eV (cleaned samples) below the Fermi level. Analogous changes in the p-type samples were from 19.6±0.1 to 18.9±0.1 eV and from 397.1±0.1 to 396.3±0.1 eV for the Ga 3d and the N 1s core levels, and from 3.0±0.1 to 1.1±0.1 eV for the UPS valence band maximum (VBM). The VBM values of the CVC samples indicate band bending of ∼0.3 eV upward on n type and ∼0.8 eV downward on p type. Electron affinities of 2.8±0.1 and 2.6±0.1 eV were determined for the clean n-type and p-type surfaces, respectively. Irrespective of doping, the CVC process left unchanged the (1×1) low energy diffraction pattern, the terraced microstructure, and the root mean square roughness observed for the surfaces of the as-loaded samples, i.e., the surface microstructure was not damaged during the high temperature exposure to ammonia at low pressure.
Uniformly valid approximations for the conformational integrals resulting from Gaussian closure in the Hookean dumbbell model with internal viscositya)

We consider a computationally more efficient calculation of the conformational integrals resulting from applying a Gaussian closure to evaluate the higher moments of the end‐to‐end vector, Q, in the Hookean dumbbell model with internal viscosity. First, these integrals are expressed as functions of the eigenvalues of the chain conformation tensor 〈QQ〉. Subsequently, they are evaluated analytically in certain characteristic limiting cases. These results are then used to construct uniformly valid approximations for the integrals. The relative error incurred in these approximations, as measured by a comparison with the results obtained through a direct numerical evaluation, has been shown to be uniformly small, i.e., less than a few percent, in the entire parameter space. Further validation of the approximations to the integrals is provided from the results obtained for the shear viscosity and first normal stress difference as a function of shear rate in a steady, homogeneous shear flow which are in excellen...
EPIPHYSEAL GROWTH: NORMAL SEQUENCE OF EVENTS AT THE EPIPHYSEAL PLATE1

MOST OF THE LABORATORY WORK on growth has been done by workers using technics such as growth curves, biochemical analyses, and histologic studies of decalcified bone and teeth. In general relatively little roentgenologic research has been done on small laboratory animals. Likewise, limited attention has been devoted to the study of the sites of calcium deposition in histologic material because decalcification is necessary before bones or teeth can be cut. After decalcification it is impossible to identify by usual methods the sites which previously contained deposits of calcium salts. In this communication new methods for the study of bone are utilized, and attention is devoted to the normal events occurring at the epiphyseal plate of the growing rat as revealed by their application. For a more detailed description of embryology and histology of the bones of the rat the reader is referred to the recent work of McLean and Bloom (I, 2).
On the representation of effective energy densities

We consider the question raised in (1) of whether relaxed energy densities involving both bulk and surface energies can be written as a sum of two functions, one depending on the net gradient of admissible functions, and the other on net singular part. We show that, in general, they cannot. In particular, if the bulk density is quasiconvex but not convex, there exists a convex and homogeneous of degree 1 function of the jump such that there is no such representation. AMS Subject Classication. 49Q15, 49Q20, 73M25, 73V25.
Travel-Style Preferences for Visiting a Novel Destination: A Conjoint Investigation across the Novelty-Familiarity Continuum

This research examines the contention made in the travel-style literature that individuals with different travel styles differ in terms of how they prefer to travel when on vacation. Study participants classified into travel-style groups evaluated conjoint profiles for a vacation to a hypothetical novel destination described in terms of three factors: type of accommodations, type of travel companions, and type of language. The findings indicated that preferences for the study factors differed by travel-style group, although not always in the direction suggested by the literature.
A 32- $\mu$ W 1.83-kS/s Carbon Nanotube Chemical Sensor System

This paper presents an energy-efficient chemical sensor system that uses carbon nanotubes (CNT) as the sensing medium. The room-temperature operation of CNT sensors eliminates the need for micro hot-plate arrays, which enables the low energy operation of the system. An array of redundant CNT sensors overcomes the reliability issues incurred by the CNT process variation. The sensor interface chip is designed to accommodate a 16-bit dynamic range by adaptively controlling an 8-bit DAC and a 10-bit ADC. A discrete optimization methodology determines the dynamic range of the DAC and the ADC to minimize the energy consumption of the system. A simple calibration technique using off-chip reference resistors reduces the DAC non-linearity. The sensor interface chip is designed in a 0.18-mum CMOS process and consumes, at maximum, 32 muW at 1.83 kS/s conversion rate. The designed interface achieves 1.34% measurement accuracy across the 10 kOmega-9 MOmega range. The functionality of the full system, including CNT sensors, has been successfully demonstrated.
Integration Site Selection by the Bacteroides Conjugative Transposon CTnBST

A newly discovered Bacteroides conjugative transposon (CTn), CTnBST, integrates more site specifically than two other well-studied CTns, the Bacteroides CTn CTnDOT and the enterococcal CTn Tn916. Moreover, the integrase of CTnBST, IntBST, had the C-terminal 6-amino-acid signature that is associated with the catalytic regions of members of the tyrosine recombinase family, most of which integrate site specifically. Also, in most of these integrases, all of the conserved amino acids are required for integration. In the case of IntBST, however, we found that changing three of the six conserved amino acids in the signature, one of which was the presumed catalytic tyrosine, resulted in a 1,000-fold decrease in integration frequency. Changes in the other amino acids had little or no effect. Thus, although the CTnBST integrase still seems to be a member of the tyrosine recombinase family, it clearly differs to some extent from other members of the family in its catalytic site. We also determined the sequence requirements for CTnBST integration in the 18-bp region where the crossover occurs preferentially during integration. We found that CTnBST integrates in this preferred site about one-half of the time but can also use other sites. A consensus sequence was tentatively derived by comparison of a few secondary sites: AATCTGNNAAAT. We report here that within the consensus region, no single base change affected the frequency of integration. However, 3 bp at one end of the consensus sequence (CTG) proved to be essential for integration into the preferred site. This sequence appeared to be at one end of a 7-bp crossover region, CTGNNAA. The other bases could vary without affecting either integration frequency or specificity. Thus, in contrast to well-studied site-specific recombinases which require homology throughout the crossover region, integration of CTnBST requires homology at one end of the crossover region but not at the other end.
Molecular dynamics simulation of a synthetic four-α-helix bundle that binds the anesthetic halothane

The structural features of binding sites for volatile anesthetics are examined by performing a molecular dynamics simulation study of the synthetic four-α-helix bundles (Aα2)2, which are formed by association of two 62-residue di-α-helical peptides. The peptide bundle (Aα2)2 was designed by Johansson et al. [Biochemistry 37 (1998) 1421–1429] and was shown experimentally to have a high affinity for the binding of the anesthetic halothane (CF3CBrClH) in a hydrophobic cavity. Since (Aα2)2 can exhibit either the anti or syn topologies, the two distinct bundles are simulated both in the presence and in the absence of halothane. Nanosecond length molecular dynamics trajectories were generated for each system at room temperature (T=298 K). The structural and dynamic effects of the inclusion of halothane are compared, illustrating that the structures are stable over the course of the simulation; that the (Aα2)2 bundles have suitable pockets that can accommodate halothane; that the halothane remains in the designed hydrophobic cavity in close proximity to the Trp residues with a preferred orientation; and that the dimensions of the peptide are perturbed by the inclusion of an anesthetic molecule.