cssi/SciSciGPT-SciSciNet huggingface dataset:
Heterostructure Microwave Transistors for Ultra-High-Speed Electronics

Ultra-high-speed operation will be required primarily in fiber-optic communication links, millimeter-wave military systems and advanced test instrumentation. To meet these needs, a new generation of heterostructure microwave transistors, fabricated on silicon, GaAs and InP, is emerging. This overview paper discusses the key characteristics, applications, and the future outlook for these transistors and their monolithic circuit implementation.
The Children's Headache Assessment Scale (CHAS): Factor structure and psychometric properties

This study investigated the content validity, factor structure, and psychometric properties of the Children's Headache Assessment Scale (CHAS), a parent rating scale for identifying environmental variables associated with pediatric headache. In Study 1, input from physicians and psychologists was obtained to develop a revised set of 44 items receiving high endorsement. In Study 2, the questionnaire was administered to parents of 92 child headache sufferers, ages 6–16, and readministered 2 weeks later. An exploratory factor analysis revealed five factors (Disruptive Impact, Social Consequences, Stress Antecedents, Physical Antecedents and Quiet Coping, and Prescription Medication Use) that reflect distinct environmental concomitants of childhood headache. Scale reliabilities (alpha, .64–.82) indicate acceptable internal consistency, and test-retest reliabilities indicate relatively stable factors and items. High scores on the Disruptive Impact factor were associated with more severe, lengthy, and infrequent headache occurrence, lending initial support for the validity of this factor. Overall, the findings support the clinical and research utility of the CHAS in behavioral treatment of childhood headache.
Stochastic modeling of atomic receiver clock for high integrity gps navigation

The Global Positioning System (GPS) was designed as a passive radio navigation system to provide positioning capability without the need for receiver clock synchronization to GPS time. In theory, a GPS receiver equipped with a high-quality receiver clock can provide better system performance. More importantly for integrity-driven navigation applications, the additional redundancy provided by a clock dynamic model can increase fault detection performance and availability for receiver autonomous integrity monitoring (RAIM). In the work presented here, a stochastic model is used to rigorously account for the time correlation of random errors in high-quality GPS receiver clocks. A batch estimator (BE) is then developed to use GPS measurements collected over time to estimate current user position. The BE incorporates the stochastic clock model to ensure that position errors are properly quantified and, therefore, that navigation integrity is ensured. The resulting improvement in positioning performance is demonstrated using covariance analysis.
MICROWAVE AND CONVENTIONAL PRECOOKING OF HOT AND COLD PROCESSED PORK LOINS

20 barrows were used to study the effects of hot and cold processing of pork loin chops and roasts precooked by conventional or microwave methods. Cooking time, losses, palatability and histological characteristics were determined. Precooking of hot processed chops appeared unfeasible due to decreased tenderness related to muscle contraction. Precooking of hot processed roasts by conventional roasting appeared feasible because of lower cooking losses and acceptable tenderness as compared to that of cold processed roasts. Microwave precooking of chops and roasts was less desirable than conventional precooking because of increased cooking losses and decreased tenderness. Sarcomere length and fiber diameter were related to muscle tenderness.
Characterizing the metastable balance between chaos and diffusion

Abstract We examine some new diagnostics for the behavior of a field ρ evolving in an advective–diffusive system. One of these diagnostics is approximately the Fourier second moment (denoted as χ2) and the other is the linear entropy or field intensity S, the latter being significantly easier to compute or measure. We establish that as a result of chaos the increasing structure in ρ is accompanied by χ increasing exponentially rapidly in time at a rate given by ρ-dependent Lyapunov exponents Λi and dominated by the largest one Λmax. Noise or diffusive coarse-graining of ρ causes χ to decrease as χ 2 ≈ 1 4 Dt , where D is a measure of the diffusion. When both effects are present the competition between the processes leads to metastability for χ followed by a final diffusive tail. The initial stages may be chaotic or diffusive depending upon the value of Λ−1max2Dχ2(0) but the metastable value of χ2 is given by χ 2∗ = ∑ i Λ i /2D irrespective. Since S =−2Dχ 2 , similar analysis applies to S, and in particular there exists a metastable decay rate for S given by S ∗ = ∑ i Λ i . These arguments are verified for a simple case, the Arnol’d Cat Map with added diffusive noise.
In line study of droplet deformation in polymer blends in channel flow

We present in situ measurements of a dilute polymer blend in channel flow using an optical flow cell placed at the exit of a twin screw extruder. At weak shear stress, we find mildly deformed ellipsoidal droplets whereas at moderate shear rates we find coexistence between large aspect ratio strings and ellipsoidal droplets. In the regime of low to moderate stress, depth resolved optical microscopy reveals that the deformation is a function of local shear stress. At large shear stress, the droplet breakup is suppressed; mildly deformed droplets at high capillary number are observed, in contrast to the Taylor model. Optical light scattering provides complementary morphological information that is averaged over the channel depth and confirms the optical microscopy. We discuss these results in terms of Taylor theory and normal forces.
Disorder Induced Phase Transition for Random 2D Dirac Fermions

We present evidence that two dimensional Dirac fermions in the presence of random Abelian gauge potential exhibit a phase transition when the disorder strength exceeds a certain critical value. We argue that this phase transition has novel properties unique to disordered systems. It resembles in many ways the transition from dilute to dense polymers phase in two dimension. In particular, we argue that the central charge of the disordered Dirac fermions, being $c=0$ before the transition, changes to $c=-2$. We discuss possible implications to quantum Hall transitions, in view of recently proposed model for quantum Hall transitions with $c=-2$.
Lunacy in the Stock Market—What is the Evidence?

Popular culture and folklore have long recognized the influence of the lunar cycle on plant, animal, and human behavior. Many of the effects have been validated in the physical and biological sciences. However, until recently such effects have been largely, if not completely ignored in the academic literature of financial economics. This study aims to contribute to answering whether there is, as some claim, a lunar influence on stock prices or volatility. The findings of this work support the Efficient Markets Hypothesis—no consistent, predictable lunar influence is found on either daily returns or daily price volatility in the Dow Jones Industrial Average, for either new or full moons. Some effects are found, but not consistent or predictable with lunar and calendar information alone.
Achieving High Sustained Performance in an Unstructured Mesh CFD Application

This paper highlights a three-year project by an interdisciplinary team on a legacy F77 computational fluid dynamics code, with the aim of demonstrating that implicit unstructured grid simulations can execute at rates not far from those of explicit structured grid codes, provided attention is paid to data motion complexity and the reuse of data positioned at the levels of the memory hierarchy closest to the processor, in addition to traditional operation count complexity. The demonstration code is from NASA and the enabling parallel hardware and (freely available) software toolkit are from DOE, but the resulting methodology should be broadly applicable, and the hardware limitations exposed should allow programmers and vendors of parallel platforms to focus with greater encouragement on sparse codes with indirect addressing. This snapshot of ongoing work shows a performance of 15 microseconds per degree of freedom to steady-state convergence of Euler flow on a mesh with 2.8 million vertices using 3072 dual-processor nodes of Sandia''s ``ASCI Red'''' Intel machine, corresponding to a sustained floating-point rate of 0.227 Tflop/s.
A Reversible Separation Method Process Using Nonionic Surfactants

Abstract An extraction method for hydrocarbons based on surfactant association structures is presented. The process utilizes the strong temperature dependence of the micellar association structures in systems of water, hydrocarbons and nonionic surfactants. The extraction is made at the HLB-temperature at which large amounts of water and oil concurrently dissolve to an isotropic solution. Reduction of the temperature (20°C) causes separation of the hydrocarbon; a corresponding increase gives separation of pure water. In this article determinations of the purity of the separated phases are reported.
Hyperkalemia Risk in Chronic Kidney Disease. Deterrent to the Use of Aldosterone Receptor Antagonism or Not

Chronic kidney disease (CKD), with or without associated comorbidities, has emerged as a global health care problem, with >1.75 million people currently being kept alive by means of dialysis or transplantation.1 This number is projected to double within the next decade. The cumulative global cost for dialysis and transplantation is predicted to exceed $1 trillion over the next decade. Preventing the development of end-stage renal disease would obviously have a significant positive impact on global health care costs, which would be of particular import for developing countries where dialysis is largely unaffordable. This economic plight is being addressed with implementation of early screening for the presence of CKD. Such screening, including measuring blood pressure (BP), serum creatinine, and urine protein excretion, carries minimal cost and is readily available.2 Once a patient is screened, cost-effective treatment measures exist that can target BP, protein excretion, smoking status, body weight, glycemic control, as well as management of hyperlipidemia. BP reduction in CKD patients can prove particularly challenging, not uncommonly requiring ≥3 antihypertensive medications, and even then, BP is often still not at goal. Reducing urine protein excretion is another modifiable risk factor for renal failure progression that is best managed with multidrug therapy. During the past 2 decades, angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and, most recently, direct renin inhibitors have emerged as preferred therapies for both the BP and proteinuria treatment aspects of CKD. Each of these drug classes, whether given individually or when combined, has a finite capacity to reduce BP/protein excretion in CKD patients; thus, it comes as …
Do bottlenecks increase additive genetic variance

Because of anthropogenic factors many populations have been at least temporarily reduced to a very small population size. Such reductions could potentially decrease genetic variation and increase the probability of extinction. Analysis of molecular markers has shown a decrease in genetic variation but in many cases this has not reduced the ability of the population to recover from the bottleneck. This apparent paradox is resolved by a consideration of how population bottlenecks can affect additive genetic variance, the relevant measure of ability to respond to selective factors. A bottleneck has the potential to increase additive genetic variance in a population. This may result in an increase in fitness, particularly in populations of conservation concern that are small and lack genetic variation. Here we present a meta-analysis of experimental tests of this prediction using models designed to fit data that is strictly additive and data that has non-additive components. This analysis shows that additive genetic variance in a dataset dominated by morphological traits increases, on average, after a bottleneck event when the inbreeding coefficient is less than 0.3, but neither of the theoretical models alone can adequately explain this result. Because of our inability at present to predict the results of a population bottleneck in a specific case and the probability of extinction associated with small population size we caution against using bottlenecks to increase genetic variance, and thus the fitness, of endangered populations.
A comment on 'on prime factor mapping for the discrete Hartley transform'

Lun and Sin (see IEEE Trans. Signal Processing, vol.40, no.6, p.1399-1411, 1982) describe a method of computing prime factor decomposed discrete Hartley transform (DHT) over N points with 2N less additions compared to the existing algorithms of Bracewell and Sorensen (1976). The author shows how the method of Lun and Siu ran be extended to eliminate the 2N extra additions in the algorithms of Bracewell and Sorenson. >
Structured LDPC codes for high-density recording: large girth and low error floor

High-rate low-density parity-check (LDPC) codes are the focus of intense research in magnetic recording because, when decoded by the iterative sum-product algorithm, they show decoding performance close to the Shannon capacity. However, cycles, especially short cycles, are harmful to LDPC codes. The paper describes the partition-and-shift LDPC (PS-LDPC) codes, a new class of regular, structured LDPC codes that can be designed with large girth and arbitrary large minimum distance. Large girth leads to more efficient iterative decoding and codes with better error-floor properties than random LDPC codes. PS-LDPC codes can be designed for any desired column weight and with flexible code rates. The paper details the girth and distance properties of the codes and their systematic construction and presents analytical and simulation performance results that show that, in the high signal-to-noise ratio region, PS-LDPC codes outperform random codes, alleviating the error floor phenomenon.
What explains small- and medium-sized apparel retailers’ international market involvement? An application of Uppsala model

The purpose of this study is to investigate U.S. small- and medium-sized apparel retailers’ international expansion by proposing a theoretical framework that incorporates the antecedents of small- and medium-sized apparel retail firms’ international market involvement. Data were collected via a self-administered questionnaire completed by apparel retailers nationwide. A total of 76 usable questionnaires were collected based on Dillman et al. (Internet, mail, and mixed-mode surveys: The tailored design method, 2009) Mail Survey technique. The results indicate that small- and medium-sized apparel retailers who have more foreign networks are likely to have foreign market knowledge. Firm age and market knowledge were found to influence a firm’s international market involvement. The results further reveal that market knowledge mediates the relationship between foreign networking and international market involvement. This study contributes to the growing knowledge base about small- and medium-sized retailers’ international expansion in the apparel industry.
Prostate Needle Biopsies Containing Prostatic Intraepithelial Neoplasia or Atypical Foci Suspicious for Carcinoma: Implications for Patient Care

Purpose: We identified information critical for patient treatment on prostate needle biopsies diagnosed with prostatic intraepithelial neoplasia or atypical foci suspicious for carcinoma.Materials and Methods: A search was performed using the MEDLINE database and referenced lists of relevant studies to obtain articles addressing the significance of finding PIN or atypical foci suspicious for carcinoma on needle biopsy.Results: There were certain results concerning PIN. 1) Low grade PIN should not be documented in pathology reports due to poor interobserver reproducibility and a relatively low risk of cancer following re-biopsy. 2) The expected incidence of HGPIN on needle biopsy is between 5% and 8%. 3) Although the diagnosis of HGPIN is subjective, interobserver reproducibility for its diagnosis is fairly high among urological pathologists, and yet only moderate among pathologists without special expertise in prostate pathology. 4) The median risk recorded in the literature for cancer following the diagn...
Analysis of helium-ion scattering with a desktop computer

Abstract This paper describes a program written in an enhanced BASIC language for a desktop computer, for simulating the energy spectra of high-energy helium ions scattered into two concurrent detectors (backward and glancing). The program is designed for 512-channel spectra from samples containing up to 8 elements and 55 user-defined layers. The program is intended to meet the needs of analyses in materials sciences, such as metallurgy, where more than a few elements may be present, where several elements may be near each other in the periodic table, and where relatively deep structure may be important. These conditions preclude the use of completely automatic procedures for obtaining the sample composition directly from the scattered ion spectrum. Therefore, efficient methods are needed for entering and editing large amounts of composition data, with many iterations and with much feedback of information from the computer to the user. The internal video screen is used exclusively for verbal and numeric communications between user and computer. The composition matrix is edited on screen with a two-dimension forms-fill-in text editor and with many automatic procedures, such as doubling the number of layers with appropriate interpolations and extrapolations. The control center of the program is a bank of 10 keys that initiate on-event branching of program flow. The experimental and calculated spectra, including those of individual elements if desired, are displayed on an external color monitor, with an optional inset plot of the depth concentration profiles of the elements in the sample.
Use of Rigid and Flexible Bronchoscopy Among Pediatric Otolaryngologists

Objective To explore how rigid and flexible bronchoscopy are used in pediatric otolaryngologic practice. Design Survey. Participants Members of the American Society of Pediatric Otolaryngology who practice in the United States and Canada and were listed in the membership directory were eligible. Of the 206 members, 24 practicing outside the United States or Canada and 11 without an e-mail address or a fax machine were excluded. Hence, a questionnaire was e-mailed or faxed to 171 pediatric otolaryngologists. Main Outcome Measures Questions concerned the practice setting, type and number of bronchoscopies, indications, complications, and medicolegal cases. Results Responses were received from 120 subjects (70.2%), with 3 retired and 2 practicing only otology, leaving 115 respondents who completed at least some of the questionnaire. Rigid and flexible bronchoscopy were performed by 72.7% (56/77) of those in academic settings and by 71.1% (27/38) of those in group or solo practices. In the last 12 months, approximately 10 454 total bronchoscopies were performed, with 2052 flexible and 9117 rigid bronchoscopies. Stridor, suspected foreign body inhalation, and laryngomalacia were the most common indications for bronchoscopy. Of the 83 respondents practicing rigid and flexible bronchoscopy, 25 (30.1%) used both instruments to manage complex or repeated foreign bodies, 25 (30.1%) used both to manage patients with cystic fibrosis, and 15 (18.1%) used both to manage simple foreign bodies. Complications were reported by 15.7% of the respondents, the most common being arrhythmia. Familiarity with a case resulting in medicolegal action was reported by 32.2% of the respondents. Conclusions Rigid and flexible bronchoscopy have multiple uses in pediatric otolaryngologic practice. Also, flexible bronchoscopy appears to be emerging as a more frequently used diagnostic and therapeutic tool.
Families and Schools

Families at all economic levels are becoming increasingly ill-equipped to provide the setting that schools are designed to complement and augment in preparing the next generation. This paper describes the sources of this deficiency and indicates just what elements have come to be missing from home and community. These are conceptualized generally as social capital which is now in short supply for children and youth. A general approach to increasing the social capital available to the next generation is indicated
Sex and genetic effects on upper and lower body fat and associations with diabetes in multigenerational families of African heritage.

Abstract Very few studies have comprehensively defined the genetic and environmental influences on body fat storage in the arms and legs and their association with diabetes, especially in families of African heritage. We analyzed body fat distribution by dual-energy x-ray absorptiometry (percentage total fat, percentage trunk fat, percentage arm fat, and percentage leg fat) and fasting serum glucose in 471 individuals (mean age, 43 years) from 8 multigenerational Afro-Caribbean families (mean family size=51; 3535 relative pairs). Diabetes was inversely associated with percentage leg fat ( P = .009) and, to some extent, positively associated with percentage arm fat independent of age, sex, and body size ( P = .08), but not with anthropometric or dual-energy x-ray absorptiometric measures of total and central adiposity. Furthermore, percentage leg fat was inversely, whereas percentage arm fat was positively, associated with body mass index, waist circumference, and serum glucose ( P P P = .02) in women than in men (h2r values, 58% vs 17%, respectively). Genetic correlation ( ρ G ) between arm and leg fat was −0.61 ( P
ASSESSING INDIVIDUAL RISK ATTITUDES USING FIELD DATA FROM LOTTERY GAMES

We use information from the television game show with the highest guaranteed average payoff in the United States, Hoosier Millionaire, to analyze risktaking in a high-stakes experiment. We characterize gambling decisions under alternative assumptions about contestant behavior and preferences, and derive testable restrictions on individual risk attitudes based on this characterization. We then use an extensive sample of gambling decisions to estimate distributions of risk-aversion parameters consistent with the theoretical restrictions and revealed preferences. We find that although most contestants display risk-averse preferences, the extent of the risk aversion implied by our estimates varies substantially with the stakes involved in the different decisions.
Errata: Reanalysis of turbulence effects on short-exposure passive imaging

he standard method for modeling the atmospheric short-exposure modulation transfer function (MTF) is due to Fried. This method involves evaluating the impact of amplitude and phase modulations of the propagating wavefront after the removal of the mean wavefront tilt. This tilt is determined by a least-squares analysis. We retain a term involving the correlation between tilt-corrected phase and computed tilt vector that was formerly assumed to be zero. Inclusion of this term yields a new turbulence-strength-dependent effect that degrades performance at high integrated turbulence levels and also predicts super-resolution effects at lower integrated turbulence levels. An analytical approximation is derived from this analysis that describes the new MTF model as a function of three dimensionless parameters related to the angular frequency, system aperture diameter, and integrated turbulence strength.
Digital Access to Cultural Heritage and Scholarship in the Czech Republic

Final preprint version of article published in Slavic and East European Information Resources, Vol. 9, No. 1. © 2008 The Haworth Press. . Article copies available from The Haworth Document Delivery Service: 1-800-HAWORTH. Email address:
Culturally Competent School Leaders: The Individual and the System

Abstract Cultural competence is the knowledge, behaviors, and dispositions necessary to effectively interact with other cultural groups. Two case studies are presented which illustrate the cultural competence of administrators in urban settings. Theories are reviewed to investigate the themes of cultural competence that emerged from the professional challenges faced by the two school leaders. The article suggests individual and system supports for administrators to effectively lead and advocate for an array of diverse students and their families
Motivation for Learning and Performance

Designed for educators, researchers, practitioners, or anyone interested in maximizing human potential, Motivation for Learning and Performance outlines 50 key motivation principles based on the latest scientific evidence from the disciplines of psychology, education, business, athletics, and neurology. Using a highly applied and conversational style, the book is designed to inform the reader about how to diagnosis, analyze, and mediate learning and performance challenges influenced by motivation. The book features chapters on the biopsychology of motivation, how motivation changes across the lifespan, and the important influence of culture on motivated behavior. Three chapters are devoted to practical strategies and the implementation of motivational change. Special sections are included on enhancing motivation at work, in the classroom, in competitive environments, and during online education. Hoffman employs the innovative approach of using his interviews with "real" people including many notable personalities across diverse cultures and disciplines to illustrate motivated behavior. For example, readers will learn what motivated the colossal investment fraud masterminded by Bernie Madoff, the intimate thoughts of former NFL superstar Nick Lowery when he missed a field goal, and the joys and tribulations of Emmy-nominated "Curb your Enthusiasm" actress Cheryl Hines. The book provides a practical, applied, and multi-disciplinary resource for anyone interested in motivation and performance, but especially for university students at the graduate or undergraduate level studying education, psychology, business, leadership, hospitality, sports management, or military science. Additionally, the writing style and eclectic nature of the text will appeal to readers of non-fiction who can use the book to gain self-awareness to enhance performance of themselves or others. * Considers motivation for both learning and performance* Identifies 50 foundational principles relating to motivation* Provides research evidence supporting the foundational principles* Includes interviews from famous individuals, identifying what motivated them and why* Includes research from psychology, education, neuroscience, business, and sports* see: www.booksite.elsevier.com/9780128007792 for supplementary materials
Understanding Bohm’s Holoflux: Clearing Up a Conceptual Misunderstanding of the Holographic Paradigm and Clarifying its Signifigance to Transpersonal Studies of Consciousness

Throughout the past 31 years transpersonal anthropologists and transpersonal psychologists seeking a scientific language to discuss anomalous phenomena and the farther reaches of human nature (or to invoke a discussion of ultimate reality, universal mind or cosmic consciousness) have referred to the holographic paradigm, the conceptual origin of which is directly related to David Bohm’s implicate order theory. In 1982 and 1984 Bohm discussed the holographic paradigm’s limitations (and more specifically his concept of holomovement) to accurately represent his implicate order theory, suggesting instead the more precise conceptual reference holoflux; yet the limited publication of this correction has not been noticed by those who continue to champion the holographic paradigm. This paper reiterates Bohm’s 1982 and 1984 correction, and discusses its implications for transpersonal theory.
Wealth Creation and the Normative Structures Framework

This paper describes and explores the relationships between the concepts of wealth creation and the normative structures classification of social capital. It finds that economic and sociological perspectives on social capital are complementary and provide a more complete understanding of social capital when merged. Together they offer greater power of explanation and permit a degree of reconciliation of terminology and concepts of sociology and economics. The merged theories offer a deeper and more comprehensive understanding of the dynamics of social capital and its place in the process of wealth creation. Keywords: social capital, wealth, norms, sociology, economics
Association of coexisting morphological umbilical cord abnormality and clinical cord compromise with hypoxic and thrombotic placental histology

To assess the usefulness and limitations of placental histology when morphological umbilical cord (UC) abnormality coexists with clinical UC compromise, 5634 consecutive placentas were divided into four groups and statistically compared: group 1-182 placentas from pregnancies with clinical features of UC compromise (variable decelerations, UC entanglement, prolapse, or true knot at delivery); group 2-1355 placentas with abnormal UC morphology or insertion; group 3-152 placentas with at least one phenotype from group 1 and one from group 2; group 4-3945 placentas with no clinical or morphological UC-related phenotypes (control group).Differences were analyzed by ANOVA or χ (2). Of 68 phenotypes studied, 13 clinical and 18 placental phenotypes were statistically significant. In group 1, 2 phenotypes were most common (oligohydramnios and abnormal fetal heart rate tracing). In group 2, 6 phenotypes were most common, including 4 clinical (abnormal umbilical artery Dopplers, nonmacerated stillbirth, multiple pregnancy, and fetal growth restriction) and 2 placental. In group 3, 23 phenotypes were most common, including 7 clinical (gestational hypertension, polyhydramnios, induction of labor, cesarean section, macerated stillbirth, congenital malformations, and abnormal 3rd stage of labor) and 16 placental. The existence of clinical signs of UC compromise alone was associated with the absence of pathomorphological placental abnormalities. However, the coexistence of clinical and abnormal morphological UC phenotypes was statistically significantly associated with placental histological signs of decreased fetal blood flow, hypoxia (acute and chronic post uterine), shallow placental implantation, and/or amnion nodosum. Thus, confirmation of clinical UC compromise should not be expected on placental examination if no morphological UC abnormality or abnormal UC insertion has been found.
Role of the azadithiolate cofactor in models for [FeFe]-hydrogenase: novel structures and catalytic implications.

This paper summarizes studies on the redox behavior of synthetic models for the [FeFe]-hydrogenases, consisting of diiron dithiolato carbonyl complexes bearing the amine cofactor and its N-benzyl derivative. Of specific interest are the causes of the low reactivity of oxidized models toward H2, which contrasts with the high activity of these enzymes for H2 oxidation. The redox and acid−base properties of the model complexes [Fe2[(SCH2)2NR](CO)3(dppv)(PMe3)]+ ([2]+ for R = H and [2′]+ for R = CH2C6H5, dppv = cis-1,2-bis(diphenylphosphino)ethylene)) indicate that addition of H2 followed by deprotonation are (i) endothermic for the mixed valence (FeIIFeI) state and (ii) exothermic for the diferrous (FeIIFeII) state. The diferrous state is shown to be unstable with respect to coordination of the amine to Fe, a derivative of which was characterized crystallographically. The redox and acid−base properties for the mixed valence models differ strongly for those containing the amine cofactor versus those derived f...
The alcohol problem: Formulations and attitudes

The purpose of this lecture is to deal with the problem of alcohol as a totality rather than with any of its aspects in particular. As we progress with this 6 weeks’ course, we shall hear lectures on physiological experiments and psychological experiments, on the findings of clinical psychology and psychiatry, and on the legal, social, educational and religious aspects of the problem. You will find, throughout, that the topic of each lecture will be treated as if it constituted the quintessence of the alcohol problem. To those among you who have your own formulations, these presentations may sometimes appear to be, practically, caricatures of the problem. Those of you who have not formed definite views may feel, at each lecture, that at last you are getting the essence.It is true that some specialists are entirely limited by their own field of knowledge and see in other fields, at the utmost, some slight cotribution for which one must have just a bit of tolerance. Many of the experts who will speak to us,...
Three-Dimensional Nanoarchitectured Transparent Conducting Oxides: Synthesis, Characterization and Photovoltaic Applications

The photovoltaic materials in solar cells take multiple tasks including absorbing lights, separating the light-induced electron-hole pairs, and consequently transport charges to the corresponding metallic electrodes. These tasks, however, are often mutually conflicting. In particular, a thick PV layer is desired to absorb enough light for creating sufficient light-induced charges, while a thin PV layer is also desired to shorten the charge transport path length insider the PV layer in order to suppress recombination. Using dye-sensitized solar cells as an exploratory platform, this dilemma is mitigated using a non-traditional 3-dimensional (3-D) highly doped fluorinated SnO2 (FTO, core)-TiO2(shell) nanostructured photoanodes. The FTO core serves as conductive core for low-resistance and drift-assisted electron extraction. The thin, conformal and low-doped TiO2 shell layer is coated by atomic layer deposition, which provides a large area for anchoring dyes and maintains a large resistance against recombination.
Mean free path spectra as a tool to understand thermal conductivity in bulk and nanostructures

A rigorous derivation is given for the thermal conductivity accumulation function and mean free path (MFP) spectrum of an isotropic bulk material. The key physical insight is to express the kinetic theory integral in terms of MFP rather than frequency. Extending this framework to incorporate boundary scattering in nanostructures leads to an integral equation that transforms a material's bulk MFP spectrum into the size-dependent thermal conductivity of the nanostructure. The kernel of this transform represents the boundary scattering rule for the particular type of nanostructure. The principal benefit of this transform is that it requires only a single function, the material's bulk MFP spectrum, or equivalently its accumulation function. Explicit knowledge of the material's dispersion relation and frequency-dependent bulk MFPs is not needed, nor is a summation over polarizations, because the bulk MFP spectrum already contains this information in exactly the form required to evaluate boundary scattering. The utility of this framework is demonstrated through a case study of six models for the phonon thermal conductivity of silicon: three analytical, one gray, and two numerical.
Host-Searching Kairomones Alter Behavior of Chelonus sp. nr. curvimaculatus, a Hymenopterous Parasite of the Pink Bollworm, Pectinophora gossypiella (Saunders)

This study examines the role of behavior-modifying chemicals in host location for the braconid egg-larval parasite, Chelonus sp. nr. curvimaculatus Cameron (Hymenoptera: Braconidae). The scales of one natural and two factitious lepidopterous hosts were found to contain kairomones that released an intense and stereotyped searching response that included locomotory arrestment, antennation, ovipositor probing, and inverse klinokinesis upon antennal contact in female Chelonus , responsiveness persisting during their entire reproductive life. The chemicals were soluble in hexane and methanol, being perceived by parasites over a range of 0.1 to 0.00004-mg scale equivalents. Scales shed by ovipositing moths around deposited eggs are thought to act as odorous extensions of host eggs for Chelonus , signaling for their presence over a larger area than would be possible by host egg-derived cues alone and leading to concentrated search in probable host-infested areas. When other Lepidoptera cohabiting cotton fields scatter their body scales over a broader area of the cotton plant, the result may diminish the percent parasitization of Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) by Chelonus species.
Critique of Methods of Estimating the Variability of Metabolizable Energy from Assays with Fasted Roosters

Abstract Metabolizable energy values from assays with fasted roosters are often calculated: 1) without regard to variability in data from control roosters, 2) with chemical determination on pooled and not individual data, and 3) from data sets with statistically aberrant points removed. Data from determinations of the ME of a feather meal sample were used to examine the influence of these practices on the reported mean and variance values. Ignoring the variability of the fasted controls or pooling excreta samples did not have large effects on the means or variances of these samples. Eliminating data from roosters whose excreta weights are more than one standard deviation from the mean had little effect on the mean value but made the variance appear much smaller than it actually was. As a result of these practices, researchers may place too much confidence in their data and fail to use enough replicates (roosters) to justify that confidence.
Circulatory support systems entering the 1990's.

Cet article porte sur les systemes d'assistance circulatoire: leur necessite, leur but, leur constitution en fonction de la pathologie, l'historique de leur developpement, leur developpement futur
Mannose-Sensitive Adherence of Escherichia Coli to Epithelial Cells from Women with Recurrent Urinary Tract Infections

AbstractThe effect of D-mannose on adherence of 73 Escherichia coli strains to vaginal and buccal epithelial cells from women with recurrent urinary tract infections, and on agglutination of human and guinea pig erythrocytes was tested. Urinary, vaginal or anal isolates from women with such infections were used. Of the strains 66 (90 per cent) demonstrated adherence to epithelial cells. D-mannose inhibited completely the adherence of 25 strains (42 per cent) that adhered to vaginal cells and inhibited an additional 11 strains (18 per cent) by at least 50 per cent. Similar results were obtained with buccal cells. The inhibitory effect of D-mannose was similar regardless of the origin of the strains. Hemagglutination frequently was inhibited by D-mannose but no consistent association between hemagglutination, and epithelial cell adherence and the effect of D-mannose was observed. The results suggest that mannose-sensitive as well as mannose-resistant adhesins frequently mediate Escherichia coli adherence to...
Drug forecast: memantine, prototype of a new approach to treatment of dementia.

Objective To review the first clinically useful N-methyl-D-aspartate (NMDA) inhibitor for the treatment of dementia, memantine. Data source A MEDLINE/PUBMED search was conducted to identify pertinent studies, case reports, letters, and reviews in the English language. All articles published from 1950 to March 2003 were reviewed. Additional references were obtained from the bibliographies of these articles. Study selection All studies evaluating any aspect of memantine in humans. Data synthesis The excitatory amino acid neurotransmitter glutamate is felt to play a role in neuroinflammation and destruction of cholinergic neurons associated with dementia. Memantine is an NMDA receptor antagonist which partially blocks glutamatergic neurotransmission in the central nervous system (CNS). It is a selective, moderate affinity, noncompetitive receptor blocker that rapidly associates with and dissociates from the NMDA receptor. Memantine, that is usually dosed once or twice daily, is predominantly eliminated as unchanged drug via the renal route (renal clearance accounts for 90% of total body clearance). Use of memantine is associated with significant improvements in a number of cognitive, functional, and behavioral assessment scales used in the evaluation of cognition-enhancing drugs in dementia. Adverse effects of memantine are generally referable to the CNS and include depression, insomnia, akathisia, agitation, dizziness, drowsiness, restlessness, and hyperexcitability. Conclusion Although there is no cure for dementia, memantine may delay disease progression and improve functioning to a clinically significant extent. However, efficacy has not been consistent within trials and no comparative data with acetylcholinesterase inhibitors (AchEI) are available. In addition, there are no controlled data available regarding combination memantine-AchEI therapy. Further study data are awaited.
Inhibition of aberrant crypt foci by chemopreventive agents

The colon carcinogenic process is believed to begin with both genetic and morphological alterations in a few individual crypts. These select crypts, called aberrant crypt foci (ACF), are widely agreed upon as precursors of colon cancer. The ACF assay involves testing potential chemopreventive agents by counting the number of ACF in a carcinogen-treated colon. This assay has the advantage of not only being less expensive and time-consuming than tumor-producing studies, but will also allow the elucidation of the colon carcinogenic process by letting the researcher explore the changes that occur at a pre-cancerous stage. The ACF assay has been used most frequently in rodent models. In the rodent colon, ACF are easy to distinguish due to their distinct morphological, histological, and biological characteristics. In addition, the ACF assay has been used to look at specific genetic alterations in the crypts such as K-ras, p53, and APC mutations. Our laboratory has consistently used the ACF assay to test many potential chemopreventive agents using rats induced by the colon carcinogen azoxymethane (AOM). Potential chemopreventive agents have been tested in both the initiation or the post-initiation period Research supports the notion that aberrant crypt foci represent a true neoplastic lesion for colon cancer. By studying these lesions both grossly and genetically it may be possible to learn more about the causes of colon carcinogenesis. In addition, by testing new compounds through the ACF assay, it is possible not only to discover potentially new chemopreventive compounds, but also to discover the mechanisms behind them. Because of this, the ACF assay is an invaluable method that will help reveal the process of colon carcinogenesis.
Vestibular type I and type II hair cells. 2: Morphometric comparisons of dissociated pigeon hair cells

Morphometric properties of solitary hair cells dissociated from the semicircular canals (SCC), utricles (UTR), and lagenas (LAG) of adult white king pigeons, Columbia livia, were compared. Measurements were made of the cell body, cuticular plate and hair bundle. Cells were divided into two groups: type 1 (group 1) was predominantly type I hair cells, and type 2 (group 3) was primarily type II hair cells. Comparisons are made initially between end organs for each group. A subpopulation of short otolith hair cells was identified. Quantitative comparisons between isolated type 1 and type 2 hair cells demonstrated that type 1 hair cells were more homogeneous both within and between vestibular end organs; while they had shorter, thinner neck regions, narrower apical surfaces, with longer and thinner bodies than did type 2 hair cells. Generally, for both type 1 and type 2 hair cells, two different hair bundle shapes were present, those (unimodal) with a single sharp taper from longest to shortest stereocilia, and those (bimodal) with an initial steep taper followed by a less steep taper. An additional subtype of type 1 hair cells with short hair bundles was identified. SCC hair cells have fewer hair bundles with bimodal tapers across all cell groups when compared to UTR or LAG. All cell subtypes identified for dissociated hair cells were corroborated using histologic sections.
What America’s Safest City might tell us about a changing America

America’s Safest City is an essential addition to the classics of criminological control theory, namely Travis Hirschi’s Causes of Delinquency and Robert Sampson’s Great American City. It provides new ideas about empathy and trust, and how social control is layered across institutions of family, schools, and community. America’s Safest City is also about the American Dream of home ownership in advantageous suburban communities. But the American Dream is no longer as accessible to under-employed college graduates; their student debt is at all-time highs, with the return on educational investments increasingly in doubt. Instead of suburbia being a roadway to a good adult life, this paper suggests that it may increasingly look like a suburban “cul de sac.”
A quantitative method for determining a representative detection limit of the forensic luminol test for latent bloodstains

The luminol test has been used for over 60 years by forensic investigators for presumptive identification of blood and visualization of blood splatter patterns. Multiple studies have estimated the limit of detection (LD) for bloodstains when luminol is employed, with results ranging from 100× to 5,000,000× dilute. However, these studies typically have not identified and controlled important experimental variables which may affect the luminol LD for bloodstains. Without control of experimental parameters in the laboratory, variables which affect the potential of presumptive bloodstain test methods remain largely unknown, and comparisons required to establish new, more powerful detection methods are simply impossible. We have developed a quantitative method to determine the relationship between the amount of blood present and its reaction with luminol by measuring, under controlled conditions, the resulting chemiluminescent intensity with a video camera, combined with processing of the digital intensity data. The method resulted in an estimated LD for bloodstains on cotton fabric at ∼200,000× diluted blood with a specific luminol formulation. Although luminol is the focus of this study, the experimental protocol used could be modified to study effects of variables using other blood detection reagents.
The sociology of speed: digital, organizational, and social temporalities

‘The control of time is thoroughly enmeshed with the dynamics of power’ (p. 3). Judy Wajcman and Nigel Dodd offer this succinct admonition in the introduction to their edited volume, aptly subtitle...
Thinking Processes Associated with Undergraduate Chemistry Students’ Success at Applying a Molecular-Level Model in a New Context

This study investigated relationships between the thinking processes that 28 undergraduate chemistry students engaged in during guided discovery and their subsequent success at reasoning through a transfer problem during an end-of-semester interview. During a guided-discovery laboratory module, students were prompted to use words, pictures, and symbols to make their mental models of chemical compounds added to water explicit, both prior to the start (initial model) and at the end (refined model) of the module. Based on their responses to these model assignments, we characterized students’ knowledge and thinking processes, including the extent to which individual students engaged in (a) constructing molecular-level models that were consistent with experimental evidence; (b) constructing molecular-level models that progressed toward scientific accuracy; (c) constructing molecular-level models that were scientifically correct; (d) making connections between laboratory observations and the molecular-level beh...