cssi/SciSciGPT-SciSciNet huggingface dataset:
HMD Type and Spatial Ability: Effects on the Experiences and Learning of Students in Immersive Virtual Field Trips

We report on the results of a study in the context of place-based immersive VR (iVR) geoscience education that compares the experiences and learning of 45 students after going through an immersive virtual field trip, using either a lower-sensing but scalable Oculus Quest or a higher-sensing but tethered HTC Vive Pro. Our results suggest that with content design considerations, standalone HMDs can be a viable replacement for high-end ones in large-scale educational studies. Furthermore, our results also suggest that the spatial ability of students can be a determining factor for their experiences and learning.
Streamlined wildland-urban interface fire tracing (SWUIFT): Modeling wildfire spread in communities

Abstract The wildland-urban interface (WUI) is defined as a geographic area where human developments and flammable vegetation merge in a wildfire-prone environment. Losses due to wildfire have been rising in the past decade, attributed to changes in vegetation growth, fuel availability, and increased land developments in WUI. This paper studies the process of wildfire spread inside WUI communities. The fire spread rate within WUI communities is determined for nine wildfires that were ranked among the most destructive wildfires in North America. An improved quasi-empirical model that considers radiation and fire spotting as modes of fire spread inside a community is proposed. The new model is validated using the documented spread rates during the 2007 Witch and Guejito fires and the 2017 Tubbs fire. The proposed model is computationally efficient and can be used to quantify fire spread rate and the number of affected structures inside a community during a wildfire event.
Effective diffusivity for a mixed-matrix membrane

The effective diffusivity or permeability of a mixed-matrix membrane composed of spherical fillers of one material distributed within a continuous matrix of another material is computed by a boundary-element method. The boundary value of the concentration of the diffusing species on the surface of the fillers is proportional to that of the adjoining matrix phase according to a linear sorption/desorption kinetics law that is responsible for an interfacial partition coefficient, while the diffusive flux is continuous across the interface. The solution of Laplace’s equation for the concentration field is constructed in terms of the single- and double-layer harmonic potentials involving the boundary values and boundary distribution of the normal derivative of the concentration and the free-space Green’s function of Laplace’s equation in three dimensions according to the standard boundary-integral formulation. The effective permeability of the membrane depends on the ratio of the filler-to-matrix permeabilities and not separately on the diffusivity ratio and partition coefficient. The results are in excellent agreement with the predictions of existing analytical models for random and ordered distributions of spherical particles within an infinite, continuous medium in the entire range of filler volume fractions considered. Extensions to systems governed by an interfacial contact resistance and nonlinear interfacial kinetics are discussed.
Sex differences in neural mechanisms of social and non-social threat monitoring.

Abstract Adolescent males and females differ in their responses to social threat. Yet, threat processing is often probed in non-social contexts using the error-related negativity (ERN; Flanker EEG Task), which does not yield sex-specific outcomes. fMRI studies show inconsistent patterns of sex-specific neural engagement during threat processing. Thus, the relation between threat processing in non-social and social contexts across sexes and the effects perceived level of threat on brain function are unclear. We tested the interactive effect of non-social threat-vigilance (ERN), sex (N = 69; Male=34; 11–14-year-olds), and perceived social threat on brain function while anticipating feedback from ‘unpredictable’, ‘nice’, or ‘mean’ purported peers (fMRI; Virtual School Paradigm). Whole-brain analyses revealed differential engagement of precentral and inferior frontal gyri, putamen, anterior cingulate cortex, and insula. Among males with more threat-vigilant ERNs, greater social threat was associated with increased activation when anticipating unpredictable feedback. Region of interest analyses revealed this same relation in females in the amygdala and anterior hippocampus when anticipating mean feedback. Thus, non-social threat vigilance relates to neural engagement depending on perceived social threat, but peer-based social contexts and brain regions engaged, differ across sexes. This may partially explain divergent psychosocial outcomes in adolescence.
A Fragile Foundation -- The Role of "Intermodal" and "Facilities-Based" Competition in Communications Policy

The communications industry is currently experiencing extensive and rapid deregulation. The policies justifying this deregulation have been constructed upon the concepts of intermodal and facilities-based competition. At both the federal and state level, regulators and courts have increasingly embraced de-regulatory policies that promote - and assume the existence of - these forms of competition. In short, these concepts have become the theoretical foundation of modern communications policy. In the rush to either embrace or reject these forms of competition, policymakers and scholars have not paused to ask whether these two concepts are descriptively meaningful. In this article, I argue that they are not - specifically, I argue that the conceptual foundations of modern policy are inconsistent with the realities of network infrastructure. As a result, the trend toward deregulation is premised upon flawed and unrealistic conceptual foundations. This article outlines these conceptual inconsistencies along with their regulatory implications. To be clear, I do not oppose deregulation, but instead call for a renewed focus on network infrastructure in regulatory proceedings.
Semiclassical nonadiabatic dynamics based on quantum trajectories for the O(P3,D1)+H2 system

The O(P3,D1)+H2→OH+H reaction is studied using trajectory dynamics within the approximate quantum potential approach. Calculations of the wave-packet reaction probabilities are performed for four coupled electronic states for total angular momentum J=0 using a mixed coordinate/polar representation of the wave function. Semiclassical dynamics is based on a single set of trajectories evolving on an effective potential-energy surface and in the presence of the approximate quantum potential. Population functions associated with each trajectory are computed for each electronic state. The effective surface is a linear combination of the electronic states with the contributions of individual components defined by their time-dependent average populations. The wave-packet reaction probabilities are in good agreement with the quantum-mechanical results. Intersystem crossing is found to have negligible effect on reaction probabilities summed over final electronic states.
An Ecologic Study of the Habitat Types of Theodore Roosevelt National Memorial Park, North Dakota

The objectives of this study, begun in May 1978, are to delimit the habitat types of Theodore Roosevelt National Memorial Park (TRNMP), North Dakota, list the plants present, and assess the animal components of the habitat types. For TRNMP a comprehensive study of the habitat types has not been done previously. The habitat type concept was developed to assess the ecologic status of forest vegetation of the Northern Rockies (Daubenmire 1952, Daubenmire and Daubenmire 1968); and the same concept was later used to assess steppe vegetation of Washington (Daubenmire 1970). The habitat type approach to assessing the ecologic status of vegetation has been used in a number of studies throughout the Rocky Mountain region (Pfister et al. 1977, Reed 1971, 1976, Wirsing and Alexander 1975, Hoffman and Alexander 1976). The basic ecologic nature of the habitat type concept lends itself to studying forest and grassland vegetation as well as interspersed shrublands (Daubenmire 1973). It has been shown that once established for a given region, habitat types provide the framework for establishing relationships between the habitat types and productivity, disease susceptibility, potential for forage production, soil moisture relations, and small mammal distributions (Daubenmire 1973, Hoffman 1960, Layser 1974, Mackee 1970, Rickard 1960). The study at TRNMP will provide data on habitat types and their major animal components and will offer opportunity for future assessment of soil moisture relations, productivity and other characteristics of a basic or applied nature.
Restriction endonuclease analysis of Eikenella corrodens.

Eikenella corrodens is a gram-negative facultative bacillus commonly found in the oral cavity. Although the role of E. corrodens in periodonititis is not clear, its isolation from extraoral infections attests to its pathogenic potential. Previous studies suggested that this species is phenotypically diverse. In the present study, we used restriction endonuclease analysis (REA) to assess the genetic diversity of this species and to explore the applicability of REA in studying the transmission of E. corrodens. Two groups of E. corrodens isolates were used in this study. Group 1 included 47 epidemiologically independent isolates recovered from dental plaques in periodontally healthy subjects and periodontitis patients and from extraoral infections in different geographic areas. Group 2 E. corrodens included 40 isolates recovered from two periodontitis patients and two periodontally healthy subjects. The results indicated that E. corrodens is genetically heterogeneous, as determined by REA. The majority of the group 1 E. corrodens isolates exhibited strain-specific restriction patterns. Forty restriction patterns were distinguishable among the 47 isolates. Analyses of group 2 isolates revealed that three of four subjects harbored more than one clonal type of E. corrodens. In one instance, a periodontitis patient was found to be colonized by six different clones. Furthermore, two different clonal types of E. corrodens were recovered from a single periodontal pocket in this patient. The results indicated that REA may be a useful tool in the epidemiologic investigation of E. corrodens infections. Images
Arc-parallel strain in a short rollback-subduction system: The structural evolution of the Crotone basin (northeastern Calabria, southern Italy)

[1] Calabria, located in southern Italy, is the exposed part of the forearc in the Ionian/Tyrrhenian subduction-rollback boundary. We present a tectonic model for the evolution of Calabria during the last 12 Ma that incorporates the structure and stratigraphy of the Crotone basin. At the re-initiation of rollback, we document listric normal faults that accommodated a deep-rooted extensional regime. Extension ceased in the Tortonian and did not continue throughout rollback. The middle Tortonian to early Messinian is characterized by distal sedimentation despite rapid rollback. Westward verging thrusts in Tortonian sediments and olistrostrome deposits within the Messinian section can be explained by instabilities in the accretionary wedge during the Messinian salinity crisis. Tectonic quiescence returned to the basin after the crisis and continued until a north-south shortening event in the middle Pliocene. Our kinematic data and new evidence of two basin inversions suggest arc-parallel shortening of the forearc. We propose that this shortening correlates with the passage of the forearc through the Apulia-Nubia narrow. This data also dispute previous interpretations of the Crotone basin as a pull-apart or transtensional basin. The identification of the main structures in the Crotone basin suggest a shift from quiescence to upheaval, beginning with Pliocene arc-parallel shortening associated with the passage of the forearc through the Apulia-Nubia narrow and continuing until today.
CSTAR database for advanced test systems

The CSTAR (cards status tracking recording) database tracks inventory redesign/failure history of the field replaceable units (cards and components) that make up the VLSI device advanced test systems (ATS) that have been designed and manufactured at IBM, East Fishkill. CSTAR obsoletes the process of logging hardware failures in a notebook where inventory and failure-to-repair actions can not be easily identified. CSTAR provides an automatic serial number generator facility for new card tracking, status histories of all cards, SQL reports for analyzing failure histories for the most frequently used repair process, engineering change summaries per card, and a comprehensive user's guide (on-line and hard copy.) CSTAR runs in a distributed environment with LANs providing the link to a centralized database enabling all information to be immediately available to all authorized users in the laboratory and manufacturing test areas. Since repair attempts now have a consistent approach, second and third shift problem take over is accelerated and simplified, and hardware maintenance programs are forecasted, there is enhanced equipment reliability by reduced unplanned maintenance and quicker turn around time. >
Child Support and Father-Child Contact: Testing Reciprocal Pathways

I use three waves of panel data to examine the relationship between child support payments and fathers’ contact with their nonmarital children. I disaggregate support into fathers’ formal and informal payments and incorporate cross-lagged effects models to identify the direction of causality between payments and contact. After including the behavior from the prior wave (lagged term) and a rich set of family characteristics, I find a marginally significant effect of paying formally at Time 1 on the likelihood of contact at Time 2 but no effect of contact at Time 1 on formal payments at Time 2. In the first examination of the relationship between informal support and father-child contact, I find a strong, positive reciprocal relationship between the likelihood and frequency of father-child contact and the likelihood and amount of informal support, with slightly stronger and more consistent effects of contact on payments than of payments on contact.
A Fast Global Fitting Algorithm for Fluorescence Lifetime Imaging Microscopy Based on Image Segmentation

Global fitting algorithms have been shown to improve effectively the accuracy and precision of the analysis of fluorescence lifetime imaging microscopy data. Global analysis performs better than unconstrained data fitting when prior information exists, such as the spatial invariance of the lifetimes of individual fluorescent species. The highly coupled nature of global analysis often results in a significantly slower convergence of the data fitting algorithm as compared with unconstrained analysis. Convergence speed can be greatly accelerated by providing appropriate initial guesses. Realizing that the image morphology often correlates with fluorophore distribution, a global fitting algorithm has been developed to assign initial guesses throughout an image based on a segmentation analysis. This algorithm was tested on both simulated data sets and time-domain lifetime measurements. We have successfully measured fluorophore distribution in fibroblasts stained with Hoechst and calcein. This method further allows second harmonic generation from collagen and elastin autofluorescence to be differentiated in fluorescence lifetime imaging microscopy images of ex vivo human skin. On our experimental measurement, this algorithm increased convergence speed by over two orders of magnitude and achieved significantly better fits.
Effects of musical training on sound pattern processing in high-school students.

Abstract Objective Recognizing melody in music involves detection of both the pitch intervals and the silence between sequentially presented sounds. This study tested the hypothesis that active musical training in adolescents facilitates the ability to passively detect sequential sound patterns compared to musically non-trained age-matched peers. Methods Twenty adolescents, aged 15–18 years, were divided into groups according to their musical training and current experience. A fixed order tone pattern was presented at various stimulus rates while electroencephalogram was recorded. The influence of musical training on passive auditory processing of the sound patterns was assessed using components of event-related brain potentials (ERPs). Results The mismatch negativity (MMN) ERP component was elicited in different stimulus onset asynchrony (SOA) conditions in non-musicians than musicians, indicating that musically active adolescents were able to detect sound patterns across longer time intervals than age-matched peers. Conclusions Musical training facilitates detection of auditory patterns, allowing the ability to automatically recognize sequential sound patterns over longer time periods than non-musical counterparts.
Estimation of returns to scale using data envelopment analysis

Abstract Generalization of the measure of returns-to-scale from a single number to an interval permits extension of the concept to DEA data domains with multiple inputs and multiple outputs. The key new approach is a partition of the optimal frontier into three parts corresponding, respectively to increasing, constant, and decreasing returns to scale. These parts are characterized in terms of optimal primal solutions, and optimal dual solutions for both the original Charnes, Cooper, Rhodes model (1978) and the later Banker, Charnes, Cooper model (1984) and relying on concepts developed by R.D. Banker (1984) and R.M. Thrall (1988).
The Effects of a Break in Water Fluoridation on the Development of Dental Caries and Fluorosis

Durham, NC, fluoridated since 1962, had an 11-month cessation of fluoridation between September, 1990, and August, 1991. The purpose of this study was to assess the effects of this break on the development of caries and fluorosis in children. Study participants were continuously-resident children in Kindergarten through Grade 5 in Durham's elementary schools. There were 1696 children, 81.4% of those eligible, for whom a questionnaire was completed and clinical data recorded. Age cohorts were defined by a child's age at the time that fluoridation ceased. Caries was recorded in children in the Birth Cohort through Cohort 3, and fluorosis for children in Cohorts 1 through 5. Caries was assessed in the primary first and second molars according to the decayed-filled index; fluorosis on the labial surfaces of the upper permanent central and lateral incisors was assessed by the Thylstrup-Fejerskov (TF) index. Mother's education was associated with caries; higher education of the mother had an odds ratio of 0.53 (95% CI 0.40, 0.76) for caries in the child. No cohort effects could be discerned for caries. Overall prevalence of fluorosis was 44%. Prevalence in Cohorts 1, 2, 3, 4, and 5 was 39.8%, 32.3%, 33.0%, 62.3%, and 57.1%, respectively. These cohort differences remained statistically significant in regression analysis. It was concluded that while the break had little effect on caries, dental fluorosis is sensitive to even small changes in fluoride exposure from drinking water, and this sensitivity is greater at 1 to 3 years of age than at 4 or 5 years.
Clinical significance of benign glands at surgical margins in robotic radical prostatectomy specimens.

OBJECTIVES Completion of robotic radical prostatectomy compared with conventional open retropubic radical prostatectomy can result in different alterations in the prostatectomy specimens. One difference appears to be an increased incidence of benign glands at the margins, which has been associated with an increase in postoperative prostatic-specific antigen (PSA) levels. We compared the frequency and clinical significance of benign prostate glands at the surgical margins in radical prostatectomy specimens obtained by robotic versus open retropubic prostatectomy. METHODS We reviewed 38 consecutive prostatectomy specimens from patients with biopsy-proven prostate cancer. Of these 38 specimens, 25 (65%) were obtained by robotic resection and 13 (35%) by open retropubic prostatectomy. Each case was analyzed for Gleason score, pathologic stage, including margin status, and the presence or absence of benign glands at the surgical margin. The study endpoint was the postoperative serum PSA level. RESULTS A significantly greater incidence (P = 0.035) of benign glands at the surgical margins was found within the robotic group compared with the open retropubic prostatectomy group (54% versus 15%). With a median follow-up of 12.5 months for the robotic group and 24.5 months for the robotic prostatectomy group, only 2 patients, who also had had positive surgical margins, had a continued and persistent increase in the postoperative PSA level after an initial nadir. CONCLUSIONS The early clinical follow-up data of our study have suggested that patients undergoing robotic radical prostatectomy with negative surgical margins achieve a PSA nadir of less than 0.1 ng/mL, irrespective of the presence or absence of benign prostatic tissue at the surgical margins.
Field Experiments on Sensitive Organizational Topics

Organizational scholars study a number of sensitive topics that make employees and organizations vulnerable to unfavorable views. However, the typical ways in which researchers study these topics—via laboratory experiments and field surveys—can be laden with problems. In this article, the authors argue that the difficulties in studying sensitive topics can be overcome through the underutilized method of field experiments, detail strategies for conducting high-quality experimental field studies, and offer suggestions for overcoming potential challenges in data collection and publishing. As such, this article is designed to serve as a guide and stimulus for using the valuable methodological tool of field experiments.
Risk of malignancy with long-term immunosuppression in renal transplant recipients

Risk of malignancy with long-term immunosuppression in renal transplant recipients. Background Improvements in immunosuppressive regimens have significantly enhanced patient and graft survival in renal transplant recipients. However, susceptibility to neoplastic disorders is increased as a consequence of prolonged immunosuppression. Available data pertaining to cancer risks in renal transplant recipients have been inconsistent, and much of it is derived from international studies, which may not be truly representative of the United States population. Methods We studied a total of 1979 transplants performed in 1739 patients from a single center in the United States with a mean follow-up of 6.1 years, and a total of 9852 person-years' follow-up. Results The mean age at the time of diagnosis of cancer was 50 years, and the mean interval between transplant and diagnosis of cancer was 95 months. Older patients receiving a transplant had a significantly higher risk for developing cancer as opposed to younger patients (RR 6.2 for >60 years compared with P = 0.01). When stratified by age groups, younger age at transplant ( P 10 years had an SIR of 2.4 ( P Conclusion We believe that this study is representative of the United States' renal transplant population, and highlights the need for reduced immunosuppression in the long-term and increased vigilance for cancers in younger patients receiving renal transplantation.
Parameter estimation of locally stationary wavelet processes

This paper considers the extraction of information from a locally stationary process modelled by wavelet packets. A method is presented to select subprocesses that characterize the key aspects of the nonstationary process for pattern analysis. The estimated parameters of the selected subprocesses are used to infer the process' time varying behavior. The estimated parameters can be used as features in the attempt to distinguish changing states within a process or differentiate two different locally stationary processes.
The vibrational spectra of benzonitrile—d5

Abstract The infrared and Raman spectra of benzonitrile-d5 were obtained and a vibrational assignment made. These values were used to substantiate the assignment of benzonitrile.
Some genetic traits in Solomon Island populations. IV. Mid-phalangeai hair

Among 425 Lau and 467 Baegu of northern Malaita, there were no tribal differences in mid-phalangeal hair. The trait was present more often in males than in females, and after puberty than before it. Age differences were more marked for males than for females. Among 168 men 20 years of age and older in both tribes, the frequency of mid-phalangeal hair was 58.3%; among 189 women of similar age, 34.4%. These frequencies were at or just below those reported for Caucasian samples, just above that for Japanese, and considerably above those for Negroes and American Indians. Analysis of family data did not confirm the hypothesis that the absence of mid-phalangeal hair is recessive to its presence.
A method to evaluate the irritant action of certain metallic salts when in contact with the intestinal mucosa.

A method is presented for studying the action of drugs placed in the lumen of the isolated rat or guinea-pig intestine. The relative irritant action of various heavy metals is evaluated on the basis of their ability to modify normal peristaltic contractions of the excised rat intestine.
Radiative relaxation of molecular vibration of the nitric oxide molecule as a possible source of the infrared Shuttle glow

A model calculation to predict infrared Shuttle flow due to the radiative relaxation of vibration of the NO molecule is presented. Space Shuttles hit atmospheric NO molecules at a very high speed and excite vibrational and rotational motions up to the temperature of 54,000 K. With the electric dipole radiation of delta v = 1, 2, 3, and particularly 4 (v is the vibrational quantum number), the excited NO molecules emit infrared radiation before they collide with other molecules. The total radiation power is estimated to be 170 A micro-W, where A is the cross-section area of the Shuttle in sq m if no adsorption of the NO molecule takes place on the Shuttle surface. The intensity of each infrared line is calculated as a function of time, including all vibrational states up to v = 35.
Properties of Air Traffic Conflicts for Free and Structured Routing

This paper analyzes the properties of air traffic conflicts in a future free routing system against those in the current structured routing system. Simulation of en route air traffic operations (above 18,000 ft) over the contiguous United States for a 24-hour period, constructed with initial conditions from actual air traffic data, were conducted using the Future ATM Concepts Evaluation Tool (FACET). Free routes were modeled as great circle (direct) routes from origin to destination, and structured routes were derived from actual flight plans along the current system of air routes. The conflict properties analyzed in this study include: (1) Total number of conflicts; (2) Distributions of key conflict parameters; and, (3) Categorization of conflicts into independent conflicts and two types of interacting conflicts. Preliminary results (for Denver Center traffic) indicate that conflict properties in a free routing system are different from those in the current structured routing system. In particular, a free routing system has significantly fewer conflicts, involving a correspondingly smaller number of aircraft, compared to the current structured routing system. Additionally, the conflict parameter distributions indicate that free routing conflicts are less intrusive than structured routing conflicts, and would therefore require small trajectory deviations for resolution.
Landscapes in Music: Space, Place and Time in the World's Greatest Music

Music is a near global muse among the world's peoples. Music may be near universal in distribution, and it certainly is a colorful mosaic of rich diversity. As the world's communication network inc...
Infinite families of non‐embeddable quasi‐residual Menon designs

A Menon design of order h2 is a symmetric (4h2,2h2-h,h2-h)-design. Quasi-residual and quasi-derived designs of a Menon design have parameters 2-(2h2 + h,h2,h2-h) and 2-(2h2-h,h2-h,h2-h-1), respectively. In this article, regular Hadamard matrices are used to construct non-embeddable quasi-residual and quasi-derived Menon designs. As applications, we construct the first two new infinite families of non-embeddable quasi-residual and quasi-derived Menon designs. © 2008 Wiley Periodicals, Inc. J Combin Designs 17: 53–62, 2009
EEG changes from long-term physical exercise

Electrophysiologic effects of physical exercise were investigated by comparing groups of individuals who engage in regular intensive physical exercise (12 + h/week) to control subjects (2 + h/week). Electroencephalographic (EEG) activity was recorded under eyes open/closed conditions to assess baseline differences between these groups. Spectral power was less for the exercise compared to the control group in the delta band, but greater in all other bands. Mean band frequency was higher for the exercise compared to controls in the delta, theta, and beta bands. Some differences in scalp distribution for power and frequency between the exercise and control groups also were found. The findings suggest that physical exercise substantially affects resting EEG. Theoretical mechanisms for these effects are discussed.
Action of biogenic amines on crustacean chromatophores, II. Analysis of the responses of erythrophores in the fildler crab, Uca pugilator, to indolealkylamines and an eyestalk hormone☆

Abstract 1. 1. The effects of injection of certain indolealkylamines on the erythrophores of the fiddler crab, Uca pugilator , were determined. 2. 2. Among the compounds tested only those which possess a free 5-hydroxy group on the indole nucleus evoked dispersion of the red chromatophoric pigment after injection into eyestalkless Uca pugilator . 3. 3. Serotonin which was very effective in vivo failed to evoke pigment dispersion when assayed in vitro on the erythrophores in legs isolated from Uca . In contrast, red pigment-dispersing hormone from the eyestalks of Uca stimulated the erythrophores in vitro as well as in vivo . 4. 4. UML (1-methyl lysergic acid butanolamide) antagonized the action of serotonin in vivo , but was without effect on hormonally induced dispersion of the red pigment. 5. 5. Injection of serotonin resulted in a marked decrease in the red pigment-dispersing potency of the supra-oesophageal ganglia and the attached circumoesophageal connectives of the recipients. 6. 6. It is concluded that serotonin acts primarily on the central nervous system to stimulate the release of a red pigment-dispersing hormone, whereas the red pigment-dispersing hormone stimulates the erythrophores directly.
Stability of an isothermal catalytic reaction with complex rate expression

Abstract A new lumping technique for determining the stability of distributed systems described by a set of parabolic equations is developed. The method is used to investigate the stability characteristics of an isothermal reaction with a Langmuir—Hinshelwood rate expression occuring inside a catalytic slab. It is shown that when the diffusivities of the two reactants are quite different several pathological effects may occur. For example, a unique unstable steady state may exist forwhich the concentration profile continuously oscillates. These phenomena are likely to occur for certain hydrogenation and hydrogenolysis reactions which have complex rate expressions.
On the resonant interaction of spherical ion-acoustic solitons

Abstract The resonant interaction of two spherical ion-acoustic solitons is observed. A new soliton whose amplitude is approximately three times the colliding soliton's amplitude is created. The spatial growth and decay of the enhancement is noted.
The Association of Lower Urinary Tract Symptoms, Depression and Suicidal Ideation: Data from the 2005–2006 and 2007–2008 National Health and Nutrition Examination Survey

Purpose: We examine the association among depression, suicidal ideation and self-reported lower urinary tract symptoms using a large, cross-sectional, population based study.Materials and Methods: The study included 2,890 men from the 2005–2006 or 2007–2008 cycles of the NHANES (National Health and Nutrition Examination Survey) who were 40 years old or older. Men were asked if they experienced nocturia, urinary hesitancy and/or incomplete bladder emptying. The PHQ-9 (Patient Health Questionnaire-9) was used to determine the likelihood of clinical depression and suicidal ideation.Results: The prevalence of lower urinary tract symptoms was 33.7% and 10.3% for men reporting 1 and 2 or more symptoms, respectively. Moderate to severe depression (PHQ-9 score 10 or greater) and suicidal ideation were reported by 181 (6.3%) and 105 (3.6%) men, respectively. Men reporting moderate to severe depression (compared to those reporting minimal depression) had a higher odds of reporting lower urinary tract symptoms (adju...
Risk of Second Cancers in Merkel Cell Carcinoma: A Meta-Analysis of Population Based Cohort Studies

The risk of second cancers in Merkel cell carcinoma (MCC) remains uncertain since risk estimates vary worldwide. The global MCC population is growing and there is a demand for better knowledge of prognosis of this disease. The Cochrane Database of Systematic Reviews, MEDLINE, and EMBASE search engines were searched for the relevant literature between January 1999 and September 2014 by use of explicit search criteria. The main outcome was second malignancies associated with MCC patients measured by standardized incidence ratios (SIRs) or other estimates of risks. Five papers fulfilled the inclusion criteria and reported SIRs of second cancer in MCC which varied from 1.07 to 2.80. Performing meta-analysis using random effects model revealed that there was an increased risk for second malignancies due to MCC (SIR, 1.52; 95% CI, 1.10–2.11). There was a significant increase in risk for malignant melanoma (SIR, 3.09; 95% CI, 2.02–4.73) as compared to all common second malignancies among the studies. Updated knowledge about risk of second malignancies in MCC will help in better assessment of the disease prognosis and will help in optimizing the medical and surgical treatment, radiotherapy, follow-up, and surveillance procedures.
At Odds over Inbreeding: An Abandoned Attempt at Mexico/United States Collaboration to “Improve” Mexican Corn, 1940–1950

During the first years of organized agricultural research in Mexico in the 1940s, two agencies ran separate programs for corn improvement. The Rockefeller Foundation’s Office of Special Studies and the Mexican government’s Office of Experiment Stations (later called the Agricultural Research Institute) carried out research on corn with distinct aims and methods. That they differed strongly is well established in the literature. Many authors have discussed a Rockefeller Foundation program that reportedly emphasized hybrid corn, a technical choice that embodied a preference for assisting wealthy farmers who could afford hybrid corn and the necessary agricultural inputs. Conversely, these authors attribute to the Mexican program a focus on open-pollinated corn, which presumably manifested its concern for Mexico’s small farmers who saved seed. This article argues that the reverse was true. The Rockefeller Foundation program initially was committed to a type of improved open-pollinated corn while the Mexican program proceeded with a strict, U.S.-style hybrid program. I try to illuminate each group’s priority on yield, as well as additional significant, and complicating, breeding priorities that precluded any collaboration between the two.
The Manager and Mr. Chips: A Comparative Study

This paper describes a study which evaluates the ability of Army managers to provide valid instruction in writing. It documents the potentials and problems in their attempts, and suggests how those problems can be addressed through inservice programs in order to capitalize on those potentials within any organization.
Interconnections Revisiting the Future

Virtual reality (VR) transports the mind beyond the two-dimensional bounds of text and photographs; it engages the imagination and forms visual and cognitive links. VR can free participants from st...
Magnetohydrodynamic Vortex Containment for Gas Core Nuclear Propulsion, Part I: Concept Overview

An overview of a research effort to analyze the effectiveness of using magnetohydrodynamically driven Q2 vortices to contain uranium in a gas core nuclear propulsion system is presented. This is the first in a series of papers that detail the chemistry, fluid dynamics, and performance of such a system. The addition of magnetohydrodynamics is shown to be very effective in overcoming the problems associated with the original vortex containment concept by decoupling the vortex strength from the mass flow. Chemical analysis of the hydrogen-uranium-fluorine environment shows that the introduction of uranium as a fluoride will not stop fuel condensation from occurring; however, problems associated with this effect are shown to be of little consequence. A fundamental performance limit due to radiative heat transfer is found, limiting the achievable specific impulse. It is shown to be weakly dependent on the chamber pressure and with any foreseeably achievable pumping pressure is limited to approximately 1200 s. Electrical conductivity of the flow is characterized in 2-D and is shown to support the necessary current flow along the length of the high aspect ratio vortex tubes. Through analysis of the nuclear core, the reactor mass is estimated, allowing characterization of the system's performance.
Facilitating the transition from physiology to hospital wards through an interdisciplinary case study of septic shock.

In order to develop clinical reasoning, medical students must be able to integrate knowledge across traditional subject boundaries and multiple disciplines. At least two dimensions of integration have been identified: horizontal integration, bringing together different disciplines in considering a topic; and vertical integration, bridging basic science and clinical practice. Much attention has been focused on curriculum overhauls, but our approach is to facilitate horizontal and vertical integration on a smaller scale through an interdisciplinary case study discussion and then to assess its utility. An interdisciplinary case study discussion about a critically ill patient was implemented at the end of an organ system-based, basic sciences module at New York University School of Medicine. Three clinical specialists—a cardiologist, a pulmonologist, and a nephrologist—jointly led a discussion about a complex patient in the intensive care unit with multiple medical problems secondary to septic shock. The discussion emphasized the physiologic underpinnings behind the patient’s presentation and the physiologic considerations across the various systems in determining proper treatment. The discussion also highlighted the interdependence between the cardiovascular, respiratory, and renal systems, which were initially presented in separate units. After the session students were given a brief, anonymous three-question free-response questionnaire in which they were asked to evaluate and freely comment on the exercise. Students not only took away physiological principles but also gained an appreciation for various thematic lessons for bringing basic science to the bedside, especially horizontal and vertical integration. The response of the participants was overwhelmingly positive with many indicating that the exercise integrated the material across organ systems, and strengthened their appreciation of the role of physiology in understanding disease presentations and guiding appropriate therapy. Horizontal and vertical integration can be presented effectively through a single-session case study, with complex patient cases involving multiple organ systems providing students opportunities to integrate their knowledge across organ systems while emphasizing the importance of physiology in clinical reasoning. Furthermore, having several clinicians from different specialties discuss the case together can reinforce the matter of integration across multiple organ systems and disciplines in students’ minds.
Combustion and nonaqueous titration determination of carbon in plant tissues

Abstract A method for determination of total carbon and carbon-14 in biological samples by combustion and subsequent absorption and titration of carbon dioxide in organic amine is described. Results obtained with this method are comparable to those obtained with a carbon analyzer. Fifteen carbon-content determinations and sample preparations for carbon-14 liquid scintillation counting can be performed in 1 hr using this procedure.
Methotrexate infusion and folinic acid in the primary therapy of nonmetastatic gestational trophoblastic tumors

Thirty-two patients with nonmetastatic gestational trophoblastic tumors were treated with methotrexate infusion and folinic acid and the results of this therapy were compared to our prior experience with the 8-day methotrexate-folinic acid regimen. Complete remission was achieved in 22 of 32 (68.7%) patients treated with methotrexate infusion and 147 of 163 (90.2%) patients treated with the 8-day regimen (P less than 0.01). One course of chemotherapy induced complete remission in 19 (86.3%) patients treated with methotrexate infusion and 121 (82.2%) patients treated with the 8-day regimen. All 10 patients resistant to methotrexate infusion later achieved remission with other chemotherapy. Following methotrexate infusion, no patient developed myelosuppression, hepatotoxicity, or alopecia. Efforts should continue to identify new chemotherapeutic protocols that maximize remission rates and minimize toxicity and hospitalization.
Regulation of GLUT1 gene transcription by the serine/threonine kinase Akt1.

We used mouse hepatoma (Hepa1c1c7) cells to study the role of the serine/threonine kinase Akt in the induction ofGLUT1 gene expression. In order to selectively turn on the Akt kinase cascade, we expressed a hydroxytamoxifen-regulatable form of Akt (myristoylated Akt1 estrogen receptor chimera (MER-Akt1)) in the Hepa1c1c7 cells; we verified that hydroxytamoxifen stimulates MER-Akt1 activity to a similar extent as the activation of endogenous Akt by insulin. Our studies reveal that stimulation of MER-Akt1 by hydroxytamoxifen induces GLUT1 mRNA and protein accumulation to levels comparable to that induced by insulin; therefore, activation of the Akt cascade suffices to induce GLUT1 gene expression in this cell system. Furthermore, expression of a kinase-inactive Akt mutant partially inhibits the response of the GLUT1 gene to insulin. Additional studies reveal that the induction of GLUT1 mRNA by Akt and by insulin reflects increased mRNA synthesis and not decreased mRNA degradation. Our findings imply that theGLUT1 gene responds to insulin at the transcriptional level and that Akt mediates a step in the activation of GLUT1gene expression in this system.
Two- to three-year follow-up of patients with single-vessel coronary artery disease randomized to PTCA or medical therapy (results of a VA cooperative study)

Despite increasing use of percutaneous transluminal coronary angioplasty (PTCA) to treat stenotic coronary artery disease, there are relatively few prospective studies evaluating its long-term effectiveness. We prospectively randomized 212 stable patients with provocable myocardial ischemia and single-vessel subocclusive coronary disease to receive primary therapy with either PTCA or medical therapy. This report presents the clinical follow-up of these patients at a mean, after randomization, of 2.4 years for interview and 3.0 years for exercise testing. Of the 212 patients originally randomized, 175 received an extended follow-up interview, and 132 underwent exercise testing; 62% of patients in the PTCA group were angina free compared with 47% of patients in the medical group (p <0.05). Furthermore, exercise duration as measured by treadmill testing was prolonged by 1.33 minutes over baseline in the PTCA group, whereas it decreased by 0.28 minutes in the medical group (p <0.04). Although the angina-free time on the treadmill was not different (p=0.50), fewer patients in the medical group developed angina on the treadmill at 3 years than those in the PTCA group (p=0.04). By 36 months, excluding the initial randomized PTCA, use of PTCA and use of coronary artery bypass surgery were not different in the 2 treatment groups. These data indicate that some of the early benefits derived from PTCA in patients with single-vessel coronary artery disease are sustained, making it an attractive therapeutic option for these patients.
Effects of grazing and shrub removal on small mammal populations in southern New Mexico, USA

Between 1995 and 1997, grazing regimes and mesquite (Prosopis glandulosa) shrub removal were combined in a factorial arrangement to assess changes in small mammal communities on the Jornada Experimental Range in southern New Mexico. Small mammals were live-trapped biannually in winter and at the end of the growing season (fall). We examined changes in abundances, species richness, species and biomass diversity, and mean captures and biomass. Species richness did not change significantly with treatments but was seasonally higher in spring 1996 compared to the fall 1996. A decrease in species and biomass diversities were seen in fall 1996 and an increase in both diversities in fall 1997. No plots reached the same species richness, abundance, or diversity encountered during a pre-treatment study in 1993. Spring 1995 and fall 1996 revealed significant reactions to the combination of the applied treatments, yet no overall pattern can be elucidated. Environmental fluctuations such as variable rainfall and inherent stochasticity of the ecosystem may explain the lack of pattern, and only emphasizes the need for more long-term studies assessing the effects of vegetation alteration on dependent communities.
Development of a novel economical device to improve post-harvest processing practices on small farms

Abstract Consumer demand for fresh produce has increased; however, multiple microbial foodborne outbreaks in the past decade have involved fresh leafy greens. While large farms may process their own leafy greens or use an external processor that uses aqueous sanitizers, small farms may not have these options. Hence, it is important to equip small farmers with simple and effective methods to reduce on-farm pathogen contamination. The goal of this study was to develop a novel device that can improve post-harvest practices on small farms growing leafy greens. A survey was administered to identify farmers' concerns associated with the post-harvest phase of production. The results indicated that most farmers do not wash leafy greens in a sanitizing solution, but would like information on how to improve the safety of their produce. As a result of this survey, a novel sanitizing device was developed to wash, sanitize (with diluted white vinegar containing acetic acid (AA)), and dry leafy greens. The result showed that 1.6% AA for 2 min was effective against coliforms, yeast, mold, and pathogenic surrogates (Listeria, Salmonella, and Escherichia coli). Significant reduction of aerobic bacteria and coliforms were observed at 2.5% AA for 2 min and 1.6% for 2 min treatment at 3 log CFU/g and 2.28 log CFU/g respectively. The use of this device may help farmers wash and sanitize fresh leafy greens effectively, reduce the risk of foodborne pathogen contamination, and improve produce shelf-life.