cssi/SciSciGPT-SciSciNet huggingface dataset:
The effect of ureteral stent placement on post-ureteroscopy complications: a meta-analysis.

OBJECTIVES To determine, by systematic review and meta-analysis of all randomized controlled trials examining ureteral stent placement after ureteroscopy, whether the presence or absence of a stent was associated with postoperative complications. METHODS All randomized clinical trials of ureteral stent placement after ureteroscopy were identified with PubMed. The primary outcome was the occurrence of a urologic complication, defined as secondary procedure, emergency department evaluation, or hospital admission. The complication rates were compared between the stented (treatment) and unstented (control) arms of each trial as a risk difference, pooled as a weighted average across all studies, using both fixed and random-effects models. RESULTS Ten trials were identified, with a total of 891 subjects. Patients undergoing ureteral stent placement after ureteroscopy had a 4% lower occurrence of urologic complications (95% confidence interval -10.1%, 1.8%). This difference, however, failed to reach statistical significance after accounting for heterogeneity in the data (P = 0.175). CONCLUSIONS There is a slightly lower absolute risk of complication associated with the placement of a ureteral stent after ureteroscopy. However, meta-analysis of the present literature does not detect a significant difference in outcome between patients who undergo ureteral stent placement after ureteroscopy and those who do not.
Visualization of convection patterns near an evaporating meniscus using μPIV

Experimental visualizations of the three dimensional (3D) convection patterns generated near an evaporating meniscus in horizontally oriented capillary tubes are presented. These patterns are caused due to the differential evaporation along the meniscus. In this study, transparent capillary tubes with refractive index close to that of the evaporating liquid were used to minimize refraction effects and obtain velocity vectors near the walls. Polystyrene fluorescent particles of 0.5 μm diameter suspended in methanol were used to make the measurements in tubes of 75, 200 and 400 μm diameter. For the 75 μm tube, gravity was observed to have no effect on the flow patterns and an axisymmetric counter-rotating vortex pair was present along the horizontal and vertical center planes, suggesting the presence of a toroidal vortex near the meniscus. With an increase in tube size, buoyancy effects became apparent as the axisymmetric pattern broke down. A counter-rotating symmetric vortex pair was observed in the horizontal center plane, whereas in the vertical center plane, a single vortex dominated the flow and pushed the secondary vortex to a corner. Particle streak and μPIV images were obtained in multiple horizontal planes and a vertical center plane to understand this 3D flow behavior.
Meteorological rocket data processor and results from the solar eclipse of 7 March 1970.

A comprehensive digital computer program is described which automatically processes precision digitized data from conventional rocketsondes and radars to produce accurately corrected temperatures and winds together with estimated uncertainties at each point. Underlying models for the systematic errors in the Arcasonde 1A temperature sensor and the radar-tracked parachute wind sensor, and for the uncertainty in corrected results are presented. Techniques used to automatically edit, synchronize and filter data are also given. Performance is illustrated by graphical output from the eight meteorological soundings in the rocket series conducted at Wallops Island, Va., during the Mar. 7, 1970 solar eclipse. An operational version (METROK) of the program is in use at NASA Wallops Station.
Currents through thin films of aluminum nitride

The current-voltage characteristics of thin film structures consisting of two metal electrodes separated by a thin insulating layer of AlN were measured as a function of insulator thickness. In thinner structures, the dependence of the current on voltage and insulator thickness was that expected from direct electron tunneling through a trapezoidal barrier. The characteristics were used to determine the barrier energies at the metal insulator interfaces and the energy-momentum relationship over a considerable portion of the AlN forbidden energy gap. In structures with thicker insulating regions, temperature-independent currents were observed which because of their dependence on voltage and insulator thickness could not be attributed to direct electron tunneling.
Cross-Cultural Environmental Perception of Wilderness

This paper investigates the environmental perceptions of three disparate culture groups: Vermonters, non-Native Quebecers, and Native Cree of northern Quebec. All three groups were affiliated with the James Bay hydroelectric project. The hydroelectric project, per se, was not the focus of this research endeavor. Instead, this study merely took advantage of the environmental awareness promulgated by the project. The concept of “wilderness” was qualitatively employed to probe environmental perceptions cross-culturally. Pressing each group to define, locate, and assess the value of wilderness provided insight into each culture's framework regarding land use and exposed the mental scaffolding that undergirds their environmental conceptualizations.
Oxygen-induced vasodilation in pulmonary arterioles from fetal rats.

Abstract Background. Oxygen is a potent stimulus for pulmonary vasodilation in the perinatal period. Little information is available regarding mediators of oxygen-induced pulmonary vasodilation in fetal rats. We have investigated the effect of blocking several proposed mediators of oxygen-induced vasodilation on the responses of isolated, third-generation pulmonary arterioles from term fetal rats to an increase in oxygen tension. Materials and methods. Third-generation pulmonary arterioles were isolated from fetal rats at term. Arterioles were preconstricted by suffusion with “hypoxic” ( p O 2 25–40 mm Hg) solution containing 40 mM KCl. The vasodilation induced by suffusion with “normoxic” ( p O 2 90–150 mm Hg) 40 mM KCl solution was recorded for control pulmonary arterioles and for arterioles pretreated with inhibitors of nitric oxide synthase and cyclooxygenase, and blockers of bradykinin receptors and purinergic receptors. Responses to oxygen suffusion were also recorded for pulmonary arterioles denuded of endothelium. Results. Control arterioles dilated 113 ± 28% of the potassium-induced preconstriction after 60 min of normoxic suffusion. Pretreatment with indomethacin completely blocked oxygen-induced vasodilation. Inhibitors of nitric oxide synthase, blockers of bradykinin and purinergic receptors, and removal of the endothelium did not significantly change normoxic vasodilation. Conclusions. Our results are most consistent with a vasodilator product of cyclooxygenase metabolism as a primary stimulus for oxygen-induced vasodilation in isolated, third-generation pulmonary arterioles from fetal rats.
The time of synthesis and function of the rII+ Product of bacteriophage T4

A temperature-sensitive mutation in the bacteriophage T4 rII region has been used to obtain a more accurate determination of the time at which the rII product is synthesized and when it functions during the course of infection in an Escherichia coli strain lysogenic for phage λ. Temperature-shift experiments indicate that the rII gene product is first synthesized about 5 min after infection at 30°. This gene product does not begin to function before about 8 min and is required continuously until at least 20 min. The rII product can function in the absence of major DNA synthesis as shown by its activity in fluorodeoxyuridine-treated cultures. A single-burst experiment indicates that the burst size of each infected cell can be limited by a temperature shift at the appropriate time.
A contextual examination of new venture performance: entrepreneur leadership behavior, top management team heterogeneity, and environmental dynamism

Summary This study examined the relationship of entrepreneur leadership behavior (empowering and directive), top management team heterogeneity (functional, educational specialty, educational level, and skill) and industry environmental dynamism (rate of unpredicted change in number of industry establishments, number of industry employees, industry revenue, and industry research and development intensity) on new venture performance (revenue growth and employment growth) using two different samples—the Inc. 500 list of America’s fastest growing startups and a national (United States) random sample of new ventures. In dynamic industry environments, startups with heterogeneous top management teams were found to perform best when led by directive leaders and those with homogenous top management teams performed best when led by empowering leaders. Conversely in stable industry environments, startups with heterogeneous top management teams were found to perform best when led by empowering leaders and those with homogenous top management teams performed best when led by directive leaders. These findings were consistent across both samples and demonstrate the value in a contextual approach to leadership, which considers adjusting leadership behavior in accordance to factors that are both internal and external to the firm. Copyright # 2007 John Wiley & Sons, Ltd.
Surface interaction between hydrophilic gels and articular cartilage

One of the important factors to be considered in the development of new implants for use in orthopedic surgery is the effect of the artificial material on opposing natural surfaces. In the case of materials which are intended for use as joint surface replacements, it is necessary to assess the effect of the material on the cartilage surfaces with which it will articulate in the joint. Rigid or abrasive materials tend to cause irreversible damage to opposing cartilage, whereas those which are too soft and pliable have a tendency to be eroded by the opposing natural surface. An ideal material for cartilage replacement would be resilient enough to avoid damaging the opposing cartilage and yet sufficiently strong to resist wear. It is also necessary that such a material be of a form that could be easily implanted in bone and, once implanted, would remain fixed in place for long periods of time. Compounds for potential implantation which seem to fulfill some of these requirements are the hydrophilic methacrylates. This group is one of a number of methacrylate polymers which has been shown to have a relatively high degree of biocompatibility with mammalian tissue [l]. Among the hydrophilic gels with desirable characteristics are two specific polymers named poly-(2hydroxyethyl methacrylate) or polyHEMA and Hydron N. These polymers have the capacity to expand in a fluid medium as a result of the absorption of water and dissolved solutes. As a result of this expansion they change from hard, brittle substances
Persistence, Continuity, and Change in the Jamaican Working-Class Family

One of the most difficult prob lems facing the student of culture is that of deciding whether two corresponding pat terns, separated by time and/or space, are continuous, or whether they resemble each other purely by coincidence. The problem is quite familiar to students of cultural transmission and cultural change (see Steward, 1972:88-92; Social Science Re search Council, 1954:973-1002; Heine- Geldern, 1968:169-173).Historians and sociologists concerned with social change in a general way, how ever, tend to overlook the extreme impor tance of this problem, operating, instead, within an implicitly dogmatic criterion of continuity.The object of this paper is to attempt to clarify this problem and to indicate its importance to all students of social and cul tural change. Toward this end, we propose to define and distinguish between three closely related concepts centering on the problem of correspondence, to establish reasonably rigorous criteria for using them, and finally, to indicate their importance by...
Using Box-Scores to Determine a Position's Contribution to Winning Basketball Games

While it is generally recognized that the relative importance of different skills is not constant across different positions on a basketball team, quantification of the differences has not been well studied. 1163 box scores from games in the National Basketball Association during the 1996-97 season were used to study the relationship of skill performance by position and game outcome as measured by point differentials. A hierarchical Bayesian model was fit with individual players viewed as a draw from a population of players playing a particular position: point guard, shooting guard, small forward, power forward, center, and bench. Posterior distributions for parameters describing position characteristics were examined to discover the relative importance of various skills as quantified in box scores across the positions. Results were consistent with expectations, although defensive rebounds from both point and shooting guards were found to be quite important.
A new constraint on strongly coupled field theories

We propose a new constraint on the structure of strongly coupled, asymptotically free field theories. The constraint takes the form of an inequality limiting the number of degrees of freedom in the infrared description of a theory relative to the number of underlying, ultraviolet degrees of freedom. We apply the inequality to a variety of theories (both supersymmetric and nonsupersymmetric), where it agrees with all known results and leads to interesting new constraints on low energy spectra. We discuss the relation of this constraint to renormalization group c theorems.
New Molecular Precursors from the Reaction of Hydrazine and Aluminum Alkoxide for the Synthesis of Powders in the Al−O−N System

A novel low-temperature sol-gel-based process has been developed for the synthesis of amorphous and crystalline powders in the Al-O-N system. The process involves reacting aluminum tri-sec-butoxide with anhydrous hydrazine using a solvent mixture of acetonitrile (ACN) and chloroform (at60 °C) to result in solid precursors. The as-prepared precursors have been pyrolyzed in nitrogen and in anhydrous ammonia to yield amorphous and crystalline oxynitride or nitride powders. The powders have been characterized using X-ray diffraction (XRD), fourier transform infrared (FTIR), and 27 Al magic angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopy techniques. Results of the structural spectroscopic analyses conducted on the pyrolyzed powders obtained at 800 °C indicate the formation of an amorphous or nanocrystalline aluminum oxynitride containing Al bonded to O in buta-, penta-, and hexacoordination. Evidence is also presented suggesting the influence of hydrazine in facilitating replacement of the butoxy groups during heat treatment and creating molecular species containing Al-N linkages in the solid precursor. Continued heat treatment of these precursors in NH3 at 1300 °C leads to the formation of crystalline AlN. The role of hydrazine in the formation of the nitride was also verified by conducting the reaction using controlled amounts of deionized (DI) water. The addition of water competes with the nitridation ability of hydrazine leading to the formation of either oxides or oxynitrides of aluminum. The approaches thus developed demonstrate the potential and flexibility of alkoxides for synthesizing precursors that lead to either single phase of AlN or molecularly mixed composites of Al2O3, AlON, and AlN, in the Al-O-N system.
Using LINQ transformation patterns to evaluate SQL queries

The SQL Lightweight Tutoring Module (SQL-LTM) is a software tool designed to evaluate the correctness of SQL queries in order to provide useful feedback to the students and guidance in their effort to learn SQL. The XML representations of the queries are processed and analyzed in several steps in order to achieve this. One important step in this process is to transform the query into a logically equivalent one, having a different structure, which is easier to further analyze. This paper focuses on the query transformation patterns and their key role in the semantic evaluation of SQL queries of an arbitrary complexity.
The persistence of behavior and form in the organization of personal information

This study revisits managers who were first interviewed more than 10 years ago to identify their personal information management (PIM) behaviors. The purpose of this study was to see how advances in technology and access to the Web may have affected their PIM behaviors. PIM behaviors seem to have changed little over time, suggesting that technological advances are less important in determining how individuals organize and use information than are the tasks that they perform. Managers identified increased volume of e-mail and the frustration with having to access multiple systems with different, unsynchronized passwords as their greatest PIM challenges. Organizational implications are discussed. © 2008 Wiley Periodicals, Inc.
Analysis of failed nuclear plant components

Argonne National Laboratory has conducted analyses of failed components from nuclear power- gener-ating stations since 1974. The considerations involved in working with and analyzing radioactive compo-nents are reviewed here, and the decontamination of these components is discussed. Analyses of four failed components from nuclear plants are then described to illustrate the kinds of failures seen in serv-ice. The failures discussed are (1) intergranular stress- corrosion cracking of core spray injection piping in a boiling water reactor, (2) failure of canopy seal welds in adapter tube assemblies in the control rod drive head of a pressurized water reactor, (3) thermal fatigue of a recirculation pump shaft in a boiling water reactor, and (4) failure of pump seal wear rings by nickel leaching in a boiling water reactor.
The Wealth of Wives: Women, Law, and Economy in Late Medieval London – By Barbara A. Hanawalt

The author of this study demonstrates what a good historical monograph can be. Scrupulously researched, carefully argued, and deftly written, The Wealth of Wives will be of value to a wide range of...
Molecular diagnosis of necrotizing fasciitis by 16S rRNA gene sequencing and superantigen gene detection.

We report the use of molecular techniques in the diagnosis of a case of culture-negative necrotizing fasciitis occurring in a 32-year-old female with no significant past medical history and who died within 36 hours of admission. Paraffin-embedded tissue sections from the popliteal fossa region obtained at autopsy showed hemorrhage, necrosis, and mild inflammation by hematoxylin and eosin staining. Tissue gram stain showed numerous gram-positive organisms arranged in clusters. The sequences of the first 500 bp of bacterial 16S rRNA gene amplified from the lesion were identical to a Lancefield group A β-hemolytic Streptococcus pyogenes. Streptococcal pyrogenic exotoxin A and B superantigen genes were detected and an emm type 1 was determined by polymerase chain reaction and sequencing from the lesion. This confirmed the etiology of the patient's rapid deterioration with multisystem organ failure.
Rare Nuclear Reactions Induced by 14.7-MeV Neutrons

Activation cross sections for 14.7 plus or minus 0.2-Mev neutrons were measured for STA(n,n alpha ) + (n, alpha n)! reactions with Cu/sup 65/ Zn/sup 70/ , Ga/sup 71/, and Nb/sup 93/, while upper limits were set for this reaction for V/ sup 51/, Ge/sup 76/, Br/sup 81/, Rb/sup 87/, Ag/sup 107/, Ag/su p 109/, In/sup 115/, Au/sup 197/, and Tl/sup 203/. Cross-section limits also were set for (n,2p) reactions on Si/sup 29/, K/sup 41/, Sc/sup 45/, Ti/sup 50/, V/sup 51/, Mn/ sup 55/, As/sup 75/, Y/sup 89/, Nb/sup 93/, Cs/sup 133/, La/sup 139/, Pr/sup 141/ , and Tb/sup 159/; and for (n,He/sup 3/) reactions on Sc/sup 45/, Nb/sup 93/, Au/ sup 197/, and Tl/sup 205/. Cross sections were dete rmined for (n, gamma ) reactions on Y/sup 89/, Nb/sup 93/, and Pr/sup 141, and upper limi ts were set for (n,3n) reactions with Pr/sup 141/, Au/sup 197/, and Tl/sup 203. The ISTAn,np) + (n,np)! reaction was detected with Ni/sup 58/, but not with Mo/sup 92/ . A value of 520 plus or minus 120 mb was established for the former, and an upper limit set for the latter. Absolute disintegration rates were obtained by both beta and gamma spectroscopymore » counting methods. Extensive use of radiochemical separation was made in order to isolate the low-yield rare reaction products from large target samples. Statistical theory was employed (using parameters selected from a critical analysis of the literature) to make theoretical cross section estimates for many of the reactions studied. The theoretical cross sections for (n, alpha n) reactions agree remarkably well with the experimentally determined STA(n,n alpha ) + (n, alpha n)! cross section sums, thereby suggesting that the path for this reaction may be predominantly the (n, alpha n) process. For certain cases, statistical theory predicts appreciable (n,2p) cross sections at 14.7 Mev; e.g., for Cr/sup 50/, Ni/sup 55/, Kr/sup 78/, and Mo/sup It is suggested that in studies of emitted proton spectra which show an excess of low-energy protons, a contribution may be present from the (n,2p) as well as the (n,np) reaction. A new gamma at 176 plus or minus 4 kev in about 5% of 1.8-day Sc/sup 48/ decays is confirmed. (auth)« less
Pulmonary oligometastases: histological features and difficulties in determining site of origin.

INTRODUCTION Pulmonary oligometastases are resected both for diagnostic and therapeutic reasons. The histological features may be nonspecific, resulting in diagnostic difficulties. DESIGN The authors retrospectively studied the clinical and pathological features of 73 open resections of lung metastases from 64 patients to determine the frequency and types of problems in establishing site of origin. RESULTS There were 18 primary organ sites, the most frequent being colon (n = 10), head and neck (9 squamous and 6 salivary gland), kidney (n = 7), and soft tissue (n = 7). Unusual histological features included detached alveolar tumor clusters at the periphery (83% of adenocarcinomas), lepidic spread (2 metastatic pancreatic tumors), and entrapped pneumocyte-lined cysts (6 tumors). A majority of squamous carcinomas from the head and neck presented difficulties in regard to excluding a second primary, especially 4 with basaloid features that mimicked primary basaloid lung carcinoma. Other tumors mimicking lung primaries included pancreatic, endometrial, and breast metastases. Germ-cell tumors, sarcomas, melanomas, and sarcomatoid carcinomas presented diagnostic difficulties. Overall, comparison with the primary tumor with or without immunohistochemical studies was performed in 38 of 73 cases (52%). CONCLUSIONS Pulmonary oligometastases comprise a wide range of histological types and often require careful pathological evaluation to determine primary site of origin.
Early and late outcomes in minimally invasive mitral valve repair: An eleven-year experience in 707 patients

Objective This study analyzes a single institution experience with minimally invasive mitral valve repair and evaluates long-term surgical outcomes of morbidity, mortality, and rates of reoperation. Late follow-up of mitral regurgitation and left ventricular function were also assessed. Methods Between August 1996 and October 2007, minimally invasive mitral valve repair was performed in 713 patients (mean follow-up 5.7 years). Excluding 6 repairs with robotic assistance, an perspective analysis of the remaining 707 patients was carried forth. Mean age was 57 ± 13 years. Mean preoperative ejection fraction was 60% ± 10%. Surgical access was through a lower ministernotomy (74%), right parasternal incision (24%), right thoracotomy (1.4%), or upper ministernotomy (0.7%). Exposure of the mitral valve was through the left atrium in 58% of the cases and transeptal in 42%. A ring annuloplasty was incorporated into 680 (96%) of 707 repairs. The Kaplan–Meier and Student t test for paired samples were used for statistical analysis. Results There were 3 (0.4%) operative deaths. Perioperative morbidity included new-onset atrial fibrillation (20%), reoperation for bleeding (2%), stroke (1.9%), permanent pacemaker implantation (1.7%), deep sternal wound infection (0.7%), and aortic dissection (0.4%). Median hospital stay was 5 days. Only 31% of patients required blood transfusion during the hospital course. There were 49 (6.9%) late deaths and 34 (4.8%) failed repairs necessitating reoperation. At 11.2 years, survival was 83% (95% confidence intervals, 76.5–88.1); freedom from reoperation was 92% (95% confidence intervals, 86.2–94.9). Nine (1.3%) patients were lost to follow-up. A total of 2369 patient-years of echocardiography time were obtained in 544 patients (mean 4.36 years, range 0.47–11.09). Mean grade of mitral regurgitation decreased from 3.80 to 1.42 ( P P Conclusion Minimally invasive mitral valve repair is safe, with low perioperative morbidity, low rates of recurrent mitral regurgitation, and low rates of reoperation and death at late follow-up.
Cardiopulmonary Limited Ultrasound Examination for "Quick-Look" Bedside Application

Although taking a "quick look" at the heart using a small ultrasound device is now feasible, a formal ultrasound imaging protocol to augment the bedside physical examination has not been developed. Therefore, we sought to evaluate the diagnostic accuracy and prognostic value of a cardiopulmonary limited ultrasound examination (CLUE) using 4 simplified diagnostic criteria that would screen for left ventricular dysfunction (LV), left atrial (LA) enlargement, inferior vena cava plethora (IVC+), and ultrasound lung comet-tail artifacts (ULC+) in patients referred for echocardiography. The CLUE was tested by interpretation of only the parasternal LV long-axis, subcostal IVC, and 2 lung apical views in each of 1,016 consecutive echocardiograms performed with apical lung imaging. For inpatients, univariate and multivariate logistic regression analyses were performed to assess the relations between mortality, CLUE findings, age, and gender. In this echocardiographic referral series, 78% (n = 792) were inpatient and 22% (n = 224) were outpatient. The CLUE criteria demonstrated a sensitivity, specificity, and accuracy for a LV ejection fraction of ≤40% of 69%, 91%, and 89% and for LA enlargement of 75%, 72%, and 73%, respectively. CLUE findings of LV dysfunction, LA enlargement, IVC+, and ULC+ were seen in 16%, 53%, 34%, and 28% of inpatients. The best multivariate logistic model contained 3 predictors of in-hospital mortality: ULC+, IVC+ and male gender, with adjusted odds ratios (95% confidence intervals) of 3.5 (1.4 to 8.8), 5.8 (2.1 to 16.4), and 2.3 (0.9 to 5.8), respectively. In conclusion, a CLUE consisting of 4 quick-look "signs" has reasonable diagnostic accuracy for bedside use and contains prognostic information.
Eckhaus instability – a possible wavelength changing mechanism in the evolution of dislocation patterns

Abstract Phase modulations of periodic dislocation patterns observed in transmission electron microscopy (TEM) studies of some single crystalline metals, are analyzed using the methods of nonlinear dynamics. The Ginzburg–Landau (GL) equation for the soft mode instability in the weakly nonlinear regime is derived for the Walgraef–Aifantis (WA) model for a coupled system of two populations of dislocations. The bulk of results is obtained using the GL equation, and, therefore, the results are more general than the WA-model itself. We demonstrate that phase modulations of dislocation patterns can be described using the concept of the Eckhaus instability which describes one of the most fundamental “generic” mechanisms of wavelength-changing. The timescale of wavelength-changing processes in dislocation systems can be very large when the system is close to the Eckhaus stability limit. This means that metastable phase modulations of dislocation patterns can survive nearly unchanged for a long time. The results of numerical simulations for realistic values of the parameters show that the Eckhaus instability could be the underlying physical reason of modulated ladder structures of persistent slip bands (PSBs) in cyclically deformed metallic alloys.
Biomechanical and performance implications of weapon design: comparison of bullpup and conventional configurations.

Objective:Shooter accuracy and stability were monitored while firing two bullpup and two conventional configuration rifles of the same caliber in order to determine if one style of weapon results in superior performance.Background:Considerable debate exists among police and military professionals regarding the differences between conventional configuration weapons, where the magazine and action are located ahead of the trigger, and bullpup configuration, where they are located behind the trigger (closer to the user). To date, no published research has attempted to evaluate this question from a physical ergonomics standpoint, and the knowledge that one style might improve stability or result in superior performance is of interest to countless military, law enforcement, and industry experts.Method:A live-fire evaluation of both weapon styles was performed using a total of 48 participants. Shooting accuracy and fluctuations in biomechanical stability (center of pressure) were monitored while subjects used th...
Social Skills Training with Underachievers, Disruptive, and Exceptional Children.

One hundred-one fourth, fifth, and sixth graders at a Southern California elementary school were randomly assigned by classroom to either a social skills training program or a no treatment control condition. On the basis of teacher ratings, subpopulations of subjects were identified: 17 Underachievers, 40 Disruptive children, 29 children with Multiple Problems, and 15 Exceptional children. In the intervention classes, subjects were randomly assigned to groups of 6 subjects each and received training for one hour twice a week for 12 weeks. Measures of social skills, peer popularity, teacher ratings, and grade-point averages were collected to evaluate the intervention. The results indicated that subjects improved most in the area not targeted as a problem for the subject; i.e., Underachievers improved their social relationships, Disruptive children increased in academic skills, and Exceptional children increased significantly in both areas. A discussion followed of the optimum intervention strategy, building on children's existing strengths vs. targeting deficits.
Loss of energy dissipation capacity from the deadzone in linear and nonlinear viscous damping devices

In a viscous damping device under cyclic loading, after the piston reaches a peak stroke, the reserve movement that follows may sometimes experience a short period of delayed or significantly reduced device force output. A similar delay or reduced device force output may also occur at the damper’s initial stroke as it moves away from its neutral position. This phenomenon is referred to as the effect of “deadzone”. The deadzone can cause a loss of energy dissipation capacity and less efficient vibration control. It is prominent in small amplitude vibrations. Although there are many potential causes of deadzone such as environmental factors, construction, material aging, and manufacture quality, in this paper, its general effect in linear and nonlinear viscous damping devices is analyzed. Based on classical dynamics and damping theory, a simple model is developed to capture the effect of deadzone in terms of the loss of energy dissipation capacity. The model provides several methods to estimate the loss of energy dissipation within the deadzone in linear and sublinear viscous fluid dampers. An empirical equation of loss of energy dissipation capacity versus deadzone size is formulated, and the equivalent reduction of effective damping in SDOF systems has been obtained. A laboratory experimental evaluation is carried out to verify the effect of deadzone and its numerical approximation. Based on the analysis, a modification is suggested to the corresponding formulas in FEMA 356 for calculation of equivalent damping if a deadzone is to be considered.
From Nerds to Normals: The Recovery of Identity among Adolescents from Middle School to High School.

Extensive attention has been given to understanding the nature of adolescent identity, but little consideration has been given to the everyday social experiences and processes by which the content of teenagers' self-perceptions are formed and remain stable or change within educational settings. Since studies have focused on members of "popular" cliques or "deviant" subcultures, it is important to examine the daily lives of teenagers whose peers have labeled them unpopular "nerds" in schools to document how these adolescents are able to overcome the stigma of this label. Using intensive interviews and observations, this study delineated the impact of school activities, school social structure, and peer culture on the self-perceptions of nerds. The findings indicate that adolescents who were unpopular in middle school and who became involved in high school activities and friendship groups were able to recover by becoming self-confident and reconstructing themselves as "normal" within a changing school social system.
The Role of IQ in the Use of Cognitive Strategies to Learn Information from a Map.

Abstract The role of IQ in individual differences in real-life problem solving and strategies use was explored. Repeated trials of learning and recall of information from a map were analyzed with high IQ and average IQ Korean students. IQ correlated with the selection and use of strategies in recall. However, the performance and strategic behaviors of low-recall high IQ students and high-recall average IQ students cautions the overgeneralization of the advantage of high IQ in the selection and use of cognitive and metacognitive strategies. The individual's mind set about learning and domain-specific ability needs to be considered as compensatory mechanisms to explain the relationship between IQ and strategies use.
Quantitative analysis of the hydrogen peroxide formed in aqueous cigarette tar extracts.

We have established, for the first time, a reliable method to quantiate hydrogen peroxide (H2O2) generated in aqueous extracts of cigarette smoke tar. The aqueous tar extract was passed through a short reverse-phase column and its H2O2 concentration determined by differential pulse polarography using an automatic reference subtraction system. The H2O2 concentration increased with aging, pH and temperature; the presence of superoxide dismutase lead to lower H2O2 concentrations. This method was applied to many kinds of research and commercial cigarettes. With a few exceptions, the amount of H2O2 formed after a fixed time from each cigarette smoke was proportional to its tar yield.
Further Studies on the Folic Acid and Vitamin B12 Content of Cow's Milk

The relic acid and vitamin BI.~ content of cow's milk has been reported by Collins, Harper, Schreiber and Elvehjem (4). The colostrum from one Guernsey cow was observed to contain higher levels of these vitamins than the milk; therefore, further analyses have been made in an effort to determine the average relic acid and vitamin B~2 content of the colostrum of the various breeds of dairy cows. Since the data reported by Collins et al. (4) represent samples obtained only during the summer of 1950, the content of these vitamins in cow's milk during other seasons also was investigated.
Electron opaque structures in human platelets: which are or are not dense bodies?

The dense bodies, also referred to as delta (δ) granules, present in human platelets are the storage sites for adenine nucleotides and serotonin. Stored products released following activation are important for platelet aggregation during hemostasis. Dense bodies are easily detected in thin sections of properly fixed platelets and in unfixed, unstained whole mount preparations. It is important to determine their presence and frequency with accuracy because they are absent or markedly reduced in platelet storage pool deficiency disorders. The present study has demonstrated that identification of dense bodies as not a simple matter. There are electron dense structures, including dense rings, glycosomes, “fuzzy” balls, chains, clusters and other dense elements, that may confuse the determination of true dense bodies. Even some α granules are sufficiently electron dense to be confused with δ granules when using densitometric techniques. The present work may prevent investigators from making diagnostic errors.
Preference of human mitochondrial RNA polymerase for superhelical templates with mitochondrial promoters.

The RNA polymerase of HeLa cell mitochondria has been purified free of endonuclease and DNA topoisomerase activities, permitting evaluation of the effect of template topology on transcription in vitro . On single-stranded DNA templates, transcription is nonspecific and does not require mitochondrial DNA sequences. In contrast, duplex DNA templates are efficiently transcribed only when they (1) carry the mitochondrial D-loop region and (2) are negatively supercoiled. These findings suggest a role for template superhelicity in modulating mitochondrial transcription in vivo .
Was There a Late Archean Biospheric Explosion

There is a growing body of evidence which suggests that the evolution of the planet drives the evolution of the biosphere. There have been 2 significant stages in Earth history when atmospheric oxygen levels rose rapidly, and both appear to be associated with supercontinent cycles. The earlier biospheric event, which extends across the Archean-Proterozoic boundary (ca. 3.0-2.2 Ga), has received little attention and is the focus of this study. Recent work on the Pilbara Craton of Western Australia has shown that concretion formed by microbial activity during the diagenesis of these sediments are absent from early Archean sediments but abundant in late Archean and early Paleoproterozoic successions of the Hamersley Basin, appearing abruptly in sedimentary rocks younger than 2.7 Ga. This study suggests that their internal architecture may have been defined by the diffusion of humic acids and the formation of polymer gels during diagenesis. The data imply that the biosphere expanded suddenly shortly after 3.0 Ga and may have begun to raise the oxygen levels of the oceanic water column earlier than thought-possibly as much as 300 my earlier.
On the Cluster Sunyaev-Zeldovich Effect and Hubble Constant

This study shows one important effect of the preexistent cosmic microwave background temperature fluctuations on the determination of the Hubble constant through the Sunyaev-Zeldovich (SZ) effect of clusters of galaxies, especially when coupled with the gravitational lensing effect by the same clusters. The effect results in a broad distribution of the apparent Hubble constant. The combination of this effect with other systematic effects, such as the Loeb-Refregier effect, seems to provide an explanation for the observationally derived values of the Hubble constant currently available, which are based on the SZ effect, if the true value of the Hubble constant is 60-80 km s-1 Mpc-1. It thus becomes possible for the values of the Hubble constant measured by other techniques, which generally give a value around 60-80 km s-1 Mpc-1, to be reconciled with the SZ effect-determined values of the Hubble constant, which are systematically lower than others and have a broad distribution.
A practical global distortion correction method for an image intensifier based x-ray fluoroscopy system

X-ray images acquired on systems with image intensifiers (II) exhibit characteristic distortion which is due to both external and internal factors. The distortion is dependent on the orientation of the II, a fact particularly relevant to II's mounted on C arms which have several degrees of freedom of motion. Previous descriptions of distortion correction strategies have relied on a dense sampling of the C-arm orientation space, and as such have been limited mostly to a single arc of the primary angle, alpha. We present a new method which smooths the trajectories of the segmented vertices of the grid phantom as a function of a prior to solving the two-dimensional warping problem. It also shows that the same residual errors of distortion correction could be achieved without fitting the trajectories of the grid vertices, but instead applying the previously described global method of distortion correction, followed by directly smoothing the values of the polynomial coefficients as functions of the C-arm orientation parameters. When this technique was applied to a series of test images at arbitrary alpha, the root-mean-square (RMS) residual error was 0.22 pixels. The new method was extended to three degrees of freedom of the C-arm motion: the primary angle, alpha; the secondary angle, beta; and the source-to-intensifier distance, lambda. Only 75 images were used to characterize the distortion for the following ranges: alpha, +/- 45 degrees (Deltaalpha = 22.5 degrees); beta, +/- 36 degrees (Deltabeta = 18 degrees); lambda, 98-118 cm (Deltalambda = 10 cm). When evaluated on a series of test images acquired at arbitrary (alpha, beta, lambda), the RMS residual error was 0.33 pixels. This method is targeted at applications such as guidance of catheter-based interventions and treatment planning for brachytherapy, which require distortion-corrected images over a large range of C-arm orientations.
On Narratives and the Sense of Self

A case is made that encountering the narrative of another person is one of the ways the Self discovers itself. In finding traces of another within oneself, as one does in encountering the narrative of another, the Self is able to appreciate its own meaning. But the narrative represents more than merely capturing another’s story. In meeting the eyes and hearing the story of another, one not only takes responsibility for the Other; one begins to assume responsibility for oneself. The encounter inherent in the narrative, therefore, gives birth to the devotion of one person to another and makes possible the discovery of what one defines as being human.
Evidence for a Concerted Mechanism of Ubiquinol Oxidation by the Cytochrome bc 1 Complex

To better understand the mechanism of divergent electron transfer from ubiquinol to the iron-sulfur protein and cytochrome b L within the cytochromebc 1 complex, we have examined the effects of antimycin on the presteady state reduction kinetics of thebc 1 complex in the presence or absence of endogenous ubiquinone. When ubiquinone is present, antimycin slows the rate of cytochrome c 1 reduction by ∼10-fold but had no effect upon the rate of cytochromec 1 reduction in bc 1complex lacking endogenous ubiquinone. In the absence of endogenous ubiquinone cytochrome c 1, reduction was slower than when ubiquinone was present and was similar to that in the presence of ubiquinone plus antimycin. These results indicate that the low potential redox components, cytochrome b Hand b L, exert negative control on the rate of reduction of cytochrome c 1 and the Rieske iron-sulfur protein at center P. If electrons cannot equilibrate from cytochrome b H and b L to ubiquinone, partial reduction of the low potential components slows reduction of the high potential components. We also examined the effects of decreasing the midpoint potential of the iron-sulfur protein on the rates of cytochrome b reduction. As the midpoint potential decreased, there was a parallel decrease in the rate ofb reduction, demonstrating that the rate of breduction is dependent upon the rate of ubiquinol oxidation by the iron-sulfur protein. Together these results indicate that ubiquinol oxidation is a concerted reaction in which both the low potential and high potential redox components control ubiquinol oxidation at center P, consistent with the protonmotive Q cycle mechanism.
EEG correlates of verbal and nonverbal working memory

Background Distinct cognitive processes support verbal and nonverbal working memory, with verbal memory depending specifically on the subvocal rehearsal of items.
The Landscape of Paul Errington's Work

The 50th anniversary of the publication of Paul Errington's Of Men and Marshes will occur in 2007. Using “landscape” in a figurative as well as a physical sense, we examine Errington's life in wildlife science as well as the places where he conducted his research. While Errington's scientific work on predation has received acclaim, we argue his research also contributed to fundamental changes in cultural and popular views of wetlands. Similar to Aldo Leopold, Errington's writings transcended science and ethics as he wrote about the intrinsic values of marshes. Errington's attempts to translate his scientific experience for a wider audience ultimately contributed to public understanding of the importance of restoring wetlands. As we reflect on the public roles of wildlife professionals, Paul Errington's work provides a visible road map to follow.
MAP Estimation for Graphical Models by Likelihood Maximization

Computing a maximum a posteriori (MAP) assignment in graphical models is a crucial inference problem for many practical applications. Several provably convergent approaches have been successfully developed using linear programming (LP) relaxation of the MAP problem. We present an alternative approach, which transforms the MAP problem into that of inference in a mixture of simple Bayes nets. We then derive the Expectation Maximization (EM) algorithm for this mixture that also monotonically increases a lower bound on the MAP assignment until convergence. The update equations for the EM algorithm are remarkably simple, both conceptually and computationally, and can be implemented using a graph-based message passing paradigm similar to max-product computation. Experiments on the real-world protein design dataset show that EM's convergence rate is significantly higher than the previous LP relaxation based approach MPLP. EM also achieves a solution quality within 95% of optimal for most instances.
Cost function evaluation for the registration of clinical DTI images onto the ICBM DTI81 white matter atlas

Background and purpose: Various algorithms are available for the analysis of diffusion tensor (DTI) images. Many of these stand alone software packages require time-intensive user interactions not yet suited for routine clinical application Here, we demonstrate the use of the 'Analysis of Functional NeuroImages' (AFNI) software package, a standard for the analysis of functional magnetic resonance images (fMRI), to automatically align clinical DTI images onto the ICBM DTI81 atlas potentially enabling the combined presentation of fMRI and DTI results. Methods: Fractional anisotropy (FA) maps from seven patients diagnosed with video/EEG defined complex partial seizures were retrospectively analyzed. Affine transformations parameters for seven different cost functions provided by the 3dAllineate software tool were calculated. Alignment quality and variations of the transformation parameters were assessed. Results: Best alignment between the FA maps for each subject and the ICBM DTI81 atlas was achieved with cost functions utilizing the cost ratio (CR) (symmetrized* CR, symmetrized+ CR and unsymmetrized CR). Symmetrized* CR performed slightly better, in particular for lateral white matter structures. Relatively small variations in the transformation parameters emphasize the robustness of the transformations. Conclusions: Good alignment of FA maps to the ICBM DTI81 white matter atlas can be achieved using an automated affine transformation with software tools provided by AFNI potentially enabling the combined presentation of fMRI and DTI information. This procedure maybe readily be applied in clinical practice.