cssi/SciSciGPT-SciSciNet huggingface dataset:
Differences in resting metabolic rate between white and African-American young adults.

Objective: A reported lower resting metabolic rate (RMR) in African-American women than in white women could explain the higher prevalence of obesity in the former group. Little information is available on RMR in African-American men. Research Methods and Procedures: We assessed RMR by indirect calorimetry and body composition by DXA in 395 adults ages 28 to 40 years (100 African-American men, 95 white men, 94 African-American women, and 106 white women), recruited from participants in the Coronary Artery Risk Development in Young Adults (CARDIA), Birmingham, Alabama, and Oakland, California, field centers. Results: Using linear models, fat-free mass, fat mass, visceral fat, and age were significantly related to RMR, but the usual level of physical activity was not. After adjustment for these variables, mean RMR was significantly higher in whites (1665.07 +/- 10.78 kcal/d) than in African Americans (1585.05 +/- 11.02 kcal/d) by 80 +/- 16 kcal/d (p < 0.0001). The ethnic x gender interaction was not significant (p = 0.9512), indicating that the difference in RMR between African-American and white subjects was similar for men and women. Discussion: RMR is ~5% higher in white than in African-American participants in CARDIA. The difference was the same for men and women and for lean and obese individuals. The prevalence of obesity is not higher in African-American men than in white men. Because of these reasons, we believe that RMR differences are unlikely to be a primary explanation for why African-American women are more prone to obesity than white women.
RESPONSE OF THE FETAL LAMB KIDNEY TO VASOPRESSIN AND NOREPINEPHRINE

Following asphyxia from occlusion of the umbilical cord there is a loss of electrolytes in the urine of the fetal lamb. Since both vasopressin (VP) and catecholamine levels are elevated in fetal blood during asphyxia, experiments hove been conducted on 14 fetal lambs, chronically instrumented to determine whether there is a relationship between these hormones and the changes in renal function. Administration of VP (5.0-10 mU/kg over 1 min) increased urinary output from 0.17 to a maximum of 0.58 ml/kg/min., and urine osmolality from 149 to 310 mOsm/kg at the end of one hour. Urine sodium & chloride concentrations increased & free water clearance decreased from 0.08 to 0.02 ml/kg/min. These changes persisted over two hours after the administration of VP. Fetal BP increased only transiently by a maximum of 15 mmHg following VP. Administration of norepinephrine at a rate of 0.5 μg/kg/min. over 30 minutes resulted in an increase in urine output from 0.25 to 0.55 ml/kg/min. Urine osmolality decreased from 150 to 128 mOsm/kg. Free water clearance increased from 0.13 to 0.27 ml/kg/min., while urine sodium and chloride concentrations remained the same. Control values were achieved one hour after the end of the infusion. At this rate of administration norepinephrine had minimal and only transient effect on fetal BP, HR and plasma renin activity. Thus, in the doses given vasopressin elicited a sodium diuresis and norepinephrine a water diuresis. The combined effect of these two hormones could thus lead to a loss of water and electrolytes.
A Comparison of Directional Buoy and Fixed Platform Measurements Of Pacific Swell

Abstract The performance of the Datawell Directional Waverider and the National Data Buoy Center (NDBC) 3-m discus buoy, widely used to measure the directional properties of surface gravity waves, are evaluated through comparisons to an array of six pressure transducers mounted 14 m below the sea surface on a platform in 200-m depth. Each buoy was deployed for several months within a few kilometers of the platform. The accuracy of the platform ground-truth array was verified by close agreement of wavenumber estimates with the theoretical linear dispersion relation for surface gravity waves. Buoy and array estimates of wave energy and directional parameters, based on integration of the directional moments across the frequency band of energetic swell (0.06–0.14 Hz), are compared for a wide range of wave conditions. Wave energy and mean propagation direction estimates from both buoys agree well with the platform results. However, the Datawell buoy provides significantly better estimates of directional spread...
AppContext: differentiating malicious and benign mobile app behaviors using context

Mobile malware attempts to evade detection during app analysis by mimicking security-sensitive behaviors of benign apps that provide similar functionality (e.g., sending SMS messages), and suppressing their payload to reduce the chance of being observed (e.g., executing only its payload at night). Since current approaches focus their analyses on the types of security-sensitive resources being accessed (e.g., network), these evasive techniques in malware make differentiating between malicious and benign app behaviors a difficult task during app analysis. We propose that the malicious and benign behaviors within apps can be differentiated based on the contexts that trigger security-sensitive behaviors, i.e., the events and conditions that cause the security-sensitive behaviors to occur. In this work, we introduce AppContext, an approach of static program analysis that extracts the contexts of security-sensitive behaviors to assist app analysis in differentiating between malicious and benign behaviors. We implement a prototype of AppContext and evaluate AppContext on 202 malicious apps from various malware datasets, and 633 benign apps from the Google Play Store. AppContext correctly identifies 192 malicious apps with 87.7% precision and 95% recall. Our evaluation results suggest that the maliciousness of a security-sensitive behavior is more closely related to the intention of the behavior (reflected via contexts) than the type of the security-sensitive resources that the behavior accesses.
Biosynthesis and localization of lactate dehydrogenase X in pachytene spermatocytes and spermatids of mouse testes.

The presence and biosynthesis of the testis-specific isozyme of lactate dehydrogenase (LDH-X) in cells at various stages of spermatogenesis have been examined. Enrichment of testicular cells in various stages of spermatogenesis has been achieved by two methods: (1) cell separation by velocity sedimentation in the Elutriator rotor and (2) γ irradiation of testes to eliminate specific classes of testicular cells. Separation of cells from immature mice indicated that cells prior to the midpachytene stage contain no LDH-X. Measurement of LDH-X levels in cells separated from adult mice and in testicular homogenates prepared at various times after irradiation indicated that the highest level of LDH-X per cell (normalized for DNA content) was in spermatids. Synthesis of LDH-X was determined, after in vivo injection of [3H]valine, by measurement of the radioactivity in LDH-X precipitated with specific antiserum. After irradiation, the rate of LDH-X synthesis remained constant, despite the loss of early primary spermatocytes. In separated cells, the rate of LDH-X synthesis was highest in late pachytene spermatocytes, lower in round spermatids, and even lower, but still significant, in elongated spermatids. Therefore, the synthesis of LDH-X begins at a specific point during spermatogenesis, the midpachytene stage of spermatocyte development, and continues throughout spermatid differentiation.
Chemopreventive effects of dietary mustard oil on colon tumor development.

Fatty acid composition of dietary fat is one of the detrimental factors in colon cancer development. Fats containing omega 6-polyunsaturated fatty acids (e.g. corn oil) enhance and omega 3-polyunsaturated fatty acids (e.g. fish oil) reduce chemically-induced colon cancer in animal studies. The purpose of this study is to investigate the effects of dietary mustard oil (containing omega 3-polyunsaturated fatty acid) on azoxymethane-induced colon cancer in rats and compare with corn and fish oil treated groups. Colon tumor incidence and multiplicity were found to be 90, 75, and 50% and 1.7, 0.8, and 0.4 tumors/rat in corn, fish and mustard oil treated groups respectively. Omega-3 polyunsaturated fatty acid levels were highest in serum and colon microsomal fractions of the fish oil group followed by the mustard oil group. Corn oil group had the highest level of omega 6-polyunsaturated fatty acid levels in serum and colon microsomal fractions. The results indicate that dietary mustard oil is more effective in preventing colon cancer in rats than dietary fish oil.
Ultrasound and its evolution in perioperative regional anesthesia and analgesia

Perioperative regional anesthetic and analgesic techniques have evolved considerably over the past four decades. Perhaps, the most impressive development in recent years has been the rapid adoption and widespread utilization of ultrasound (US) guidance to perform targeted delivery of local anesthetics and catheters in a consistent manner for postoperative pain control. This article briefly reviews the history of US in regional anesthesia and perioperative analgesia, the evidence basis for this practice, the clinical application of novel techniques and imaging modalities, and possible future technology and research directions.
Sensitivity analysis for coupled thermoelastic systems

Abstract This paper presents an adjoint approach, derived from the reciprocal theorem, for the sensitivity analysis of linear dynamic thermoelastic systems. The variation of a general response functional is expressed in explicit form with respect to variations of the design fields which consist of the material properties, applied loads, prescribed boundary, initial conditions, and the structural shape. The functional is dependent on these design quantities as well as the following implicity defined response fields: displacement, temperature, stress, strain, heat flux, temperature gradient, reaction forces, and reaction surface flux. The formulation incorporates the reciprocal relation between variations of the real system design and response fields and an adjoint state. Here, convolution is employed in lieu of time mappings used in other transient adjoint sensitivity derivations. Specializations of the formulation to uncoupled, combined quasi-static uncoupled, and steady-state thermoelasticity are also presented. The finite element method is used to demonstrate the application of the formulation to a problem in automobile engine design.
Equivalent base resistance of point-contact transistors

A theoretical expression for the equivalent base resistanceR b of point-contact transistors is derived by consideration of a three-dimensional electric field problem. The analysis shows that the equivalent base resistance depends on the location of the emitter, resistivity of the semiconductor and the dimensions of the configuration.
Efficacy of a randomized trial of a community and school-based anti-violence media intervention among small-town middle school youth.

In a community randomized controlled trial, intervention middle school students from small towns were exposed to a community and school-based anti-violence intervention (“Resolve It, Solve It”). The primary intervention was a media campaign in which local high school students served as models in print, radio, and television PSAs and spearheaded local school and community activities. The media campaign was supported with school and community events that reinforced campaign messages. Tests of recognition and recall indicated widespread exposure to the media intervention. Multiple group latent growth models indicated that relative to control students, intervention students reported significant differences in rates of growth for intent for violence, physical assault against people, verbal victimization, and perceived safety at school. No differences were found for verbal assault, physical assault against objects, physical victimization, or self-efficacy for avoiding violence. When examined by sex, it was determined that results for physical assault against people were obtained only among female students, and changes in verbal victimization and perceived school safety were observed only among male students. These results suggest that a media and reinforcing community intervention led by older peers can alter rates of growth for some measures of violence and associated factors among small-town youth. Further research is indicated to determine how different campaign messages influence students by sex.
Identification of transferred DNA insertions within Arabidopsis genes involved in signal transduction and ion transport

Abstract The transferred DNA (T-DNA) of Agrobacterium tumefaciens serves as an insertional mutagen once integrated into a host plant's genome. As a means of facilitating reverse genetic analysis in Arabidopsis thaliana, we have developed a method that allows one to search for plants carrying F-DNA insertions within any sequenced Arabidopsis gene. Using PCR, we screened a collection of 9100 independent T-DNA-transformed Arabidopsis lines and found 17 T-DNA insertions within the 63 genes analyzed. The genes surveyed include members of various gene families involved in signal transduction and ion transport. As an example, data are shown for a T-DNA insertion that was found within CPK-9, a member of the gene family encoding calmodulin-domain protein kinases.
Molecular phylogeny of Azteca ants (Hymenoptera: Formicidae) and the colonization of Cecropia trees

Abstract Despite the prominence of theAzteca–Cecropiainteraction as the focus of extensive ecological investigation, a reliable phylogeny of theAztecaants has been lacking, primarily because many of the morphological and behavioral characters are phylogenetically uninformative or conflicting. A phylogenetic analysis of a select set ofAztecaants, including sixCecropiainhabitants and two non-Cecropiainhabitants, plus an outgroup taxon, is presented on the basis of mitochondrial DNA sequences. The evolutionary relationships deduced from the molecular data are analyzed with reference to ecological and morphological studies, specifically addressing the phylogenetic relationship of structurally and behaviorally ambiguous taxa, species complex groupings, and the colonization ofCecropiatrees. According to the molecular phylogeny, theCecropia-inhabitingAztecado not form a monophyletic clade, indicating multiple independent colonization or abandonment ofCecropiatrees by theAzteca.
OPEN A NEW WINDOW IN RATIONAL RESEARCH PLANNING: ADJUST ALPHA TO MAXIMIZE STATISTICAL POWER

Alternative strategies for optimizing statistical power in applied psychological research are considered. Increasing sample size and combining predictors in order to yield a useful effect size are well-known tactics for increasing power. A third approach, increasing alpha, is rarely used because of zealous adherence to convention. There are two related aspects in setting the alpha level. First, the relative seriousness of Type I and Type II errors must be considered. This assessment must then be qualified and redetermined after taking into account the prior probability that an effect exists. Procedures that make these processes objective are demonstrated. When sample size and effect size are both fixed, increasing alpha may be the only feasible strategy for maximizing power. It is concluded that a priori power analysis should be a major consideration in any test of an hypothesis, and that alpha level adjustment should be viewed as a useful strategy for increasing power.
Germinal centers in the human thymus.

This study reports the normal thymus of a 3 year old girl in which four germinal centers have been found in different lobules. They are located in the medulla, three of them in the cortico-medullary junction. Reticular cells, medium-sized and occasionally large lymphocytes, reticular macrophages and a large number of immature and mature thymocytes occupy the germinal centers. The medium-sized lymphocytes divide and give rise to smaller cells which appear to move to the peripheral zone to become thymocytes.
CD44 Splice Variant Expression in Clear Cell Carcinoma of the Ovary

Abstract Objective. CD44 is a surface glycoprotein widely distributed among different tissues. Malignant tumors may show a more complex pattern of CD44 expression, indicating a loss of splice control. The aim of our study is to investigate the expression of CD44 splice variants (CD44v) and its metastatic potential in clear cell carcinoma of the ovary. Methods. Twenty-two cases of clear cell carcinoma of the ovary were evaluated for CD44 standard form (CD44s) and splice variants: -4v, -6v, and -9v expression by immunocytochemistry. Results. Twenty-one primary ovarian tumors and 23 metastatic sites were available for evaluation. Eighteen of 21 (86%) of ovarian sections studied expressed CD44s; 15/21 (71%) expressed CD44-4v; 14/21 (67%) expressed CD44-6v; and 12/21 (57%) expressed CD44-9v. Of 23 metastatic sites evaluated, 87% expressed CD44s. In contrast, only 5 (22%) metastases had CD44-4v and CD44-6v expression and 8 (35%) had CD44-9v immunoreactivity. None of 10 normal contralateral ovaries expressed CD44s or any splice variants. In 2 cases we had tumor available from the primary surgery, and subsequent recurrences. Both recurrences showed decreased expression of CD44-4v and CD44-6v. Conclusions. Clear cell carcinoma of the ovary shows an abnormal pattern of CD44s expression and mRNA splicing when compared to the contralateral normal ovary in the same patient. Metastases of clear cell carcinoma show a downregulation in expression of some splice variants. Furthermore, we have data that suggest that as the tumors recur, CD44s and its isoforms are downregulated. Our results suggest that alternative mRNA splicing of CD44 may be important in the development of metastases from clear cell carcinoma of the ovary.
High power density energy harvester with high permeability magnetic material embedded in a rotating wheel

This work presents an alternative design of a rotating energy harvester, which possesses the capability of powering electronic sensors and wireless sensor networks within vehicle. This energy harvester design is based on magnetostatic coupling between a stationary circular-arc hard magnet array and rotating magnetic solenoids, which consists of a unique core with high permeability (μr>10,000) to significantly increase the output power density. A prototype of this rotating energy harvesting system has been fabricated and demonstrated on a rotating wheel at speeds from 10 to 60 miles/hour (mph). Test of the prototype equipped with energy storage circuit and wireless transmission board on actual vehicle has been carried out. Results of different rotating frequencies show average power densities from 1 to 5 W/cm3. A numerical and experimental study of powering a real-time wireless tire pressure monitoring system (TPMS) reveals that the energy harvester design generates constant and steady power sufficient for continuous operation of the TPMS.
Factors Influencing the pKa of Ligated Amines and the Syn/Anti Isomerization in Cysteine-Based Re(V)O(N2S2) Radiopharmaceutical Analogues As Revealed by a Novel Dominant Tautomer in the Solid State

Efficient radiopharmaceutical design demands an understanding of factors that lead to one isomeric species in one ionization state at physiological pH. Thus, all pKa values must be outside the range of 6−9 for the typical M(V)O(N2S2) (M = 99mTc, 186/188Re) agents. The pendant carboxyl group needed for rapid clearance of renal agents in particular must be either only syn or only anti to the oxo ligand with respect to the N2S2 ligand plane. Monoamide-monoamine-dithiol (monoamide-monoamine = MAMA) ligands useful in preparing radiopharmaceuticals typically form M(V)O(N2S2) complexes with one core ligand pKa of ∼6−7 (secondary amine) and with both syn and anti isomers. We designed a new MAMA ligand, mercaptoacetamide-ethylene-cysteine (MAECH5), with the electron-withdrawing carboxyl group separated by only two bonds from the NH group. Only syn-ReO(MAECH2) was isolated. The structure of the monoanion syn-[ReO(MAECH)]- in the crystal of a [AsPh4]+ salt reveals lattice H-bonding between the CO2H of a tautomer (t2...
Ribozymes and their medical implications

Certain RNA molecules can mediate their own cleavage or splicing or act as enzymes to promote reactions on substrate RNA molecules. Thus, RNA is not restricted to being a passive carrier of genetic information but can have an active role in directing cellular biochemistry. These findings suggest the possibility that other cellular RNAs, including the RNA components of small nuclear ribonucleoproteins, of the ribosome, and of various ribonucleoprotein enzymes, are catalysts. RNA enzymes (ribozymes) can be used as sequence-specific RNA cleavage agents in vitro, providing useful tools for biochemical studies of RNA. On a more speculative note, ribozymes directed against viral RNAs have the potential of serving as therapeutic agents. Finally, some infectious agents, including hepatitis 8 virus and perhaps poliovirus and rhinoviruses, are themselves ribozymes, providing potential targets for pharmaceuticals. ( JAMA 1988;260:3030-3034)
Psychiatric Disorders Among Relatives of Cocaine-Abusing Individuals

Familial risk for psychiatric disorders was assessed among 673 siblings of cocaine-abusing individuals. Various indices of familial risk were examined, including those based on the presence/absence of disorders in parents and those reflecting severity (assessed by age at onset) of disorders. Across risk indices, the findings indicated high vulnerability among siblings (1) to substance abuse in relation to paternal alcoholism and (2) to depression and substance abuse in relation to maternal depression. The validity of the Type I/Type II distinction was upheld in the context of alcoholism only among fathers. In the context of affective disorders, risk to offspring was greatest if exposure to parental psychopathology occurred during the early childhood years.
Predictors in Dynamic Nonlinear Models: Large-Sample Behavior

The large-sample behavior of one-period-ahead and multiperiod-ahead predictors for a dynamic nonlinear simultaneous system is examined in this paper. Conditional on final values of the endogenous variables, the asymptotic moments of the deterministic, closed-form, Monte Carlo stochastic, and several variations of the residual-based stochastic predictor are analyzed. For one-period-ahead prediction, the results closely parallel our previous findings for static nonlinear systems. For multiperiod-ahead prediction similar results hold, except that the effective number of sample-period residuals available for use with the residual-based predictor is T/m , where T denotes sample size. In an attempt to avoid the problems associated with sample splitting, the complete enumeration predictor is proposed which is a multiperiod-ahead generalization of the one-period-ahead residual-based predictor. A bootstrap predictor is also introduced which is similar to the multiperiod-ahead Monte Carlo except disturbance proxies are drawn from the empirical distribution of the residuals. The bootstrap predictor is found to be asymptotically inefficient relative to both the complete enumeration and Monte Carlo predictors.
Theory and experimental method for determining individual kinetic constants of fast-acting, irreversible proteinase inhibitors

Abstract A theory and experimental method are presented to characterize the kinetics of fast-acting, irreversible proteinase inhibitors. The theory is based upon formal analysis of the case of an irreversible inhibitor competing with a substrate for the active-site of a proteinase. From this theory, an experimental method is described by which the individual microscopic kinetic constants for the interaction of the inhibitor with the proteinase can be determined. These are, for a two-step inhibition reaction sequence, the equilibrium dissociation constant and the first-order rate constant for inhibition, and, for a one-step inhibition reaction sequence, the second-order rate constant for inhibition. The theory and experimental method were validated by an analysis of the inhibition of trypsin by the two-step synthetic inhibitor p-nitrophenyl p-guanidino-benzoate and the one-step protein inhibitor bovine pancreatic trypsin inhibitor. The substrate used in these experiments is a new, fluorogenic substrate for trypsin-like serine proteinases (Cbz-Ile-Pro-Arg-NH)2-Rhodamine, the synthesis and properties of which are described.
Faculty citations: An approach to assessing the impact of diminishing resources on scientific research

Abstract In an effort to assess the impact of diminished library resources on scientific research, the Georgia Institute of Technology library collection was evaluated by analyzing the sources cited in the publications of faculty in the applied and physical sciences for 1989. This study indicates that even with substantial periodical cancellations, the periodical collection supports the majority of faculty needs since they rely primarily on core journals in their disciplines. Other materials cited less frequently in published faculty research — monographs, proceedings, technical reports, other serials, and government documents — are examined. The limitations of this method, its institutionally specific results, and the need to learn more about the information-seeking behaviors of research science faculty are also discussed.
Effects of neuromuscular activity on choline acetyltransferase and acetylcholinesterase

Changes in neuromuscular activity are known to modify neuromuscular transmission. In this report, we describe changes in the activities of choline acetyltransferase (CAT) and acetylcholinesterase (AChE) in response to decreased and increased activity of skeletal muscles in the rat. Disuse atrophy of gastrocnemius muscles was produced by surgical pinning of the hind limb. Overuse hypertrophy of the plantaris muscle was produced by severing the tendon of the gastrocnemius and soleus muscles. At various times after production of disuse or overuse, the activities of CAT and AChE were measured by radiometric assay. In disused muscles, CAT activity per muscle decreased markedly (50% of control by day 7), while AChE activity per muscle decreased to a smaller extent (80% of control by day 7). The Km of CAT with respect to acetyl CoA did not change in homogenates of atrophic muscles (1 × 10−4m), suggesting that the loss of activity was not due to alteration of enzyme protein, but rather to decreased amounts of enzyme. Overuse of muscle resulted in an increase in the activities of CAT (120% of control by day 8) and AChE (142% of control by day 8). Thus, use and disuse may influence neuromuscular transmission by regulating the production of enzymes involved in the synthesis and degradation of acetylcholine.
Dose-response relationship for rat liver DNA damage caused by 1,2-dimethylhydrazine.

Abstract An experimental approach was taken to the question of dose-response curves for chemical carcinogenesis, using DNA damage as a biomarker. Female rats were given 13 different doses of 1,2-dimethylhydrazine (from 1.4 to 135000 μg/kg) and the subsequent hepatic DNA damage was determined by the alkaline elution technique. DMH doses below 450 μg/kg did not significantly damage DNA; all DMH doses of 1000 μg/kg or higher damaged rat hepatic DNA ( P x values (dose) ranged over five orders of magnitude and the y values (DNA damage) ranged 30-fold. Ten different regression models (linear, quadratic, cubic, power, and six nonlinear transition models) were compared in their ability to fit the experimental data. With respect to log transformed dose, the six nonlinear transition equations fit the data considerably better than the four power type of equations. A sigmoid model fit to the log transformed dose of 1,2-dimethlyhydrazine had an r 2 of 0.9979, a degree of freedom adjusted r 2 of 0.9969, a F -statistic of 1,457, and a fit standard error of 0.50. With respect to untransformed dose, only three equations (sigmoid, cascade and gaussian cumulative) could creditably fit the DMH data. The experimental results are interpreted with respect to hormesis, use of log transformed dose, sigmoid dose-response models, thresholds of biological response and cancer risk assessment.
Migraine and Epilepsy in the Pediatric Population

Individually, childhood epilepsy and migraine are two of the most common conditions seen in pediatric neurology. What complicates matters is that there can be marked similarities between migraine and epilepsy as well as a variety of underlying conditions that predispose children to both seizures and headache. Thus, separating epilepsy from migraine may not be easy, but can be done with a detailed history as well as timely use of ancillary testing. Once children have been diagnosed with epilepsy, migraine, or both, treatment options become essential in attempts to manage these common, yet often disabling, neurological conditions. Acute interventions tend to be condition specific while preventative options may overlap for migraine and epilepsy. In the following review, we will discuss the epidemiology of childhood epilepsy and headache, the association between them, as well as how to differentiate epilepsy from migraine. Treatment strategies will follow before concluding with a discussion on prognosis.
Atmospheric response to variations in sea surface temperature

An extended range prediction experiment was performed with the GISS atmospheric model on a global data to test the sensitivity of the model to sea surface temperature (SST) variation over a two-week forecast period. The use of an initial observed SST field in place of the climatological monthly mean sea temperatures for surface flux calculations in the model was found to have a significant effect on the predicted precipitation over the ocean, with enhanced convection computed over areas where moderately large warm SST anomalies are found. However, there was no detectable positive effect of the SST anomaly field on forecast quality. The influence of the SST anomalies on the daily predicted fields of pressure and geopotential is relatively insignificant up to about one week compared with the growth of prediction error, and is no greater over a two-week period than that resulting from random errors in the initial meteorological state. The 14-day average fields of sea level pressure and 500-mb height predicted by the model, appear to be similarly insensitive to anomalies of sea surface temperature.
Separation and characterization of human bone marrow mononuclear cells from aspirates and ribs.

Abstract Human bone marrow specimens were collected as aspirates from 17 individuals and from ribs obtained from 13 individuals undergoing thoractomy. The marrow samples were separated over discontinuous Ficoll-Hypaque gradients. Special care was taken to insure uniformity as to pH (7.2) and osmolality (298 mosM) throughout the gradients. Cells were harvested from the interfaces between each of the solutions with the preponderance of cells (60–90%) being found between the 1.060 and 1.070, and 1.077 and 1.085 g/ml solutions. These populations were predominantly mononuclear and granulocytic, respectively. Surface characteristics of the mononuclear fractions of marrow from aspirates and ribs showed marked differences in percentages of T cells (9.1 and 3.6%, respectively), B cells (25.9 and 18.7%) and calculated percentages of Null cells (non-T, non-B, non-macrophage; 45.0 and 79.5%). Mononuclear cells from bone marrow obtained by aspiration had a high spontaneous uptake of [ 3 H]thymidine and no additional response to mitogen (E-PHA, Con A, PWM) or cell surface antigen (MLC) induced stimulation. Human bone marrow mononuclear cells from ribs had a low spontaneous [ 3 H]-thymidine uptake, were able to stimulated slightly by E-PHA, and were also stimulated in MLC. These studies demonstrate that human bone marrow mononuclear cells can be easily isolated using a discontinuous Ficoll-Hypaque gradient technique and that marrow cells obtained from ribs will allow a more representative evaluation of marrow lymphoid cell function than marrow cells from conventional aspirates due to less contamination with peripheral blood in the rib samples.
Bacterial delivery of Staphylococcus aureus α-hemolysin causes regression and necrosis in murine tumors.

Bacterial therapies, designed to manufacture therapeutic proteins directly within tumors, could eliminate cancers that are resistant to other therapies. To be effective, a payload protein must be secreted, diffuse through tissue, and efficiently kill cancer cells. To date, these properties have not been shown for a single protein. The gene for Staphylococcus aureus α-hemolysin (SAH), a pore-forming protein, was cloned into Escherichia coli. These bacteria were injected into tumor-bearing mice and volume was measured over time. The location of SAH relative to necrosis and bacterial colonies was determined by immunohistochemistry. In culture, SAH was released and killed 93% of cancer cells in 24 hours. Injection of SAH-producing bacteria reduced viable tissue to 9% of the original tumor volume. By inducing cell death, SAH moved the boundary of necrosis toward the tumor edge. SAH diffused 6.8 ± 0.3 µm into tissue, which increased the volume of affected tissue from 48.6 to 3,120 µm3. A mathematical model of molecular transport predicted that SAH efficacy is primarily dependent on colony size and the rate of protein production. As a payload protein, SAH will enable effective bacterial therapy because of its ability to diffuse in tissue, kill cells, and expand tumor necrosis.
Structural features of the Nogo receptor signaling complexes at the neuron/myelin interface

Upon spinal cord injury, the central nervous system axons are unable to regenerate, partially due to the repulsive action of myelin inhibitors, such as the myelin-associated glycoprotein (MAG), Nogo-A and the oligodendrocyte myelin glycoprotein (OMgp). These inhibitors bind and signal through a single receptor/co-receptor complex that comprises of NgR1/LINGO-1 and either p75 or TROY, triggering intracellular downstream signaling that impedes the re-growth of axons. Structure-function analysis of myelin inhibitors and their neuronal receptors, particularly the NgRs, have provided novel information regarding the molecular details of the inhibitor/receptor/co-receptor interactions. Structural and biochemical studies have revealed the architecture of many of these proteins and identified the molecular regions important for assembly of the inhibitory signaling complexes. It was also recently shown that gangliosides, such as GT1b, mediate receptor/co-receptor binding. In this review, we highlight these studies and summarize our current understanding of the multi-protein cell-surface complexes mediating inhibitory signaling events at the neuron/myelin interface.
WTF? detecting students who are conducting inquiry without thinking fastidiously

In recent years, there has been increased interest and research on identifying the various ways that students can deviate from expected or desired patterns while using educational software. This includes research on gaming the system, player transformation, haphazard inquiry, and failure to use key features of the learning system. Detection of these sorts of behaviors has helped researchers to better understand these behaviors, thus allowing software designers to develop interventions that can remediate them and/or reduce their negative impacts on user outcomes. In this paper, we present a first detector of what we term WTF ("Without Thinking Fastidiously") behavior, based on data from the Phase Change microworld in the Science ASSISTments environment. In WTF behavior, the student is interacting with the software, but their actions appear to have no relationship to the intended learning task. We discuss the detector development process, validate the detectors with human labels of the behavior, and discuss implications for understanding how and why students conduct inquiry without thinking fastidiously while learning in science inquiry microworlds.
In situ cleaning method for silicon surface using hydrogen fluoride gas and hydrogen chloride gas in a hydrogen ambient

Abstract To obtain a desirable silicon substrate surface for epitaxial growth, the in situ cleaning method is studied for the first time in a hydrogen ambient at atmospheric pressure in a quartz chamber using a combination of hydrogen fluoride gas and hydrogen chloride gas. A native oxide film can be removed by anhydrous hydrogen fluoride gas at room temperature within a few minutes. Hydrogen chloride gas is used to remove an organic hydrocarbon film at 973 K in 1 min. Perfect removal of both films from the entire silicon surface is indicated by very small haze intensity of the silicon epitaxial film grown on the substrate and is also indicated by the haze intensity after baking at 1223 K in a hydrogen ambient at atmospheric pressure. It is concluded that the in situ cleaning method has high capability for epitaxy on silicon surface.
Laminar natural convection over a slender vertical frustum of a cone with variable surface temperature

The problem of laminar, natural convection flow over a slender frustum of a cone with variable surface temperature is treated in this paper. The governing differential equations are solved by a combination of quasilinearization and finite-difference methods. As an illustration of the formulation, numerical solutions are obtained for a range of Prandtl numbers (0.1 to 100) and the transverse curvature parameter for the case of power-law surface temperature distribution. The formulation presented in this paper provides a way to analyze the heat transfer over a slender frustum of a cone where both the transverse curvature and the surface temperature variation have to be considered simultaneously. On discutc, dans le present travail, le probleme d'un econlement lamiuaire a convection naturelle sur le tronc d'un cone mince dont la temperature superficiellle est variable. On resout les principales equations differentielles en combinant les methodes de quasi-linearisation et de differences finies. Pour illustrer la formation, on a obtenu des solutions numeriques pour une gamme de nombres de Prandtl (.01 a 100) ainsi que le parametre de courbure transversale, dans le cas d'unc distribution de la temperature superficielle suivant la loi de puissance. La formulation presentee dans ce travail fournit un moyen d'analyser le transfert de chaleur sur le tronc d'un cone mince, lorsque l'on doit considerer simultanement la courbure transversale et la variation de la temperature superficielle.
Simulation of Amorphous Silicon Hydride Solar Cells Using a Personal Computer

The simulation of a-Si:H solar cells has the potential to make a major contribution to the development of improved devices. However, to achieve this potential, simulations must run quickly on personal computers. This will require simplified approaches which are justified by the correspondence of their results to more elaborate but slower, running simulations.
Prevalence and structure of behavior symptoms among children in special education and regular classroom settings

Abstract Studied the factor structure of the Behavior Problem Checklist using children from a middle to upper-middle-class suburban school system, determined the extent to which factors generated from children in regular classrooms approximated those generated from children in special education, and examined the effects of class placement, sex, and the interactions of these variables on the average rating children receive on the generated factors. One hundred children from 12 classes for the emotionally disturbed or learning disabled and 527 children from regular forst-through seventh-grade classes were rated by their teachers on the Behaviors Problem Checklist. Following a varimax factor rotation, coefficients of factor congruence and analysis of variance were conducted to test the hypotheses. Results indicated that although teacher ratings of special education and normal children are structurally similar, special education children scored higher on all three factors than did their regular class counterparts. Furthermore, almost all percentages of occurance for individual items were higher for special education children. Further research is suggested to deal with a possible expectancy effect in teacher ratings of problem behaviors.
Guanylyl cyclase C (GC-C) regulates the dynamics of the proliferating compartment of intestinal crypts

Background GC-C, the receptor for bacterial heat-stable enterotoxins (STs) and the endogenous ligands guanylin and uroguanylin, regulates volume homeostasis in intestine. Beyond fluid balance, GC-C inhibits colon cancer cell proliferation, although a role of this receptor in regulating normal enterocyte dynamics remains undefined. Methods Regulation of proliferation was examined in vitro and ex vivo employing NCM460 human colon crypt cells and human colonic mucosa cells from patients, respectively. Regulation of enterocyte dynamics in vivo was examined employing null mice for GC-C expression (GC-C−/−). Results Activation of GC-C by ST induced cGMP accumulation and reduced cell cycle progression in NCM460 cells. A cell-permeant analog of cGMP, 8-br-cGMP, mimicked the effect of ST and induced a transient cell cycle delay at the G1/S transition. GC-C−/− mice exhibit increased length of the crypt-villus axis in small intestine and the crypt-lumen axis in colon. Elongation of this axis reflected expansion of the crypt proliferating compartment, populated by more rapidly cycling and migrating progenitor cells. Moreover, ST and 8-br-cGMP inhibited the proliferation of normal human colonic mucosa cells from patients. Conclusions As expression of guanylin or uroguanylin is frequently lost in colorectal tumors, the expansion of the crypt proliferating compartment in GC-C−/− mice suggests a role for this receptor as a tumor suppressor contributing to intestinal carcinogenesis. Clinical Pharmacology & Therapeutics (2005) 77, P22–P22; doi: 10.1016/j.clpt.2004.11.084
Phase Diagram of Polyelectrolyte Solutions: Weak Polymer Effect

We present a mean field theory of phase diagram of solutions of flexible polyelectrolytes with neutralizing counterions. We show that the temperature−concentration curve, corresponding to the coexi...
Modeling and implementing software architecture with acme and archJava

We demonstrate a tool to incrementally synchronize an Acme architectural model described in the Acme Architectural Description Language (ADL) with an implementation in ArchJava, an extension of the Java programming language that includes explicit architectural modeling constructs.
Relative discriminability of heartbeat-contingent stimuli under three procedures for assessing cardiac perception.

The purpose of this study was to compare the relative discriminability of heartbeat detection tasks described by Whitehead, Drescher, Heiman, and Blackwell (1977) and Katkin, Morell, Goldband, and Bernstein (1980) with a third procedure designed to capitalize on the strengths of the other two. One-hundred-and-eight subjects were given 2 blocks of 25 trials in which they attempted to discriminate whether a short train of auditory and visual pulses were contiguous with their ongoing cardiac activity. Subjects were divided into three experimental groups. When subjects were tested without knowledge of results (KR), all three procedures yielded approximately similar discrimination performances, with only the new procedure significantly exceeding that expected by chance. Over 25 trials with KR, the new procedure yielded significantly higher discrimination performance than baseline, an effect not achieved by the Katkin or Whitehead procedures. A second experiment assessed subjects' ability to discriminate S+ and S− trials in the new procedure based on a noncardiac input. Subjects could not reliably perform this discrimination.
Novel Semiactive Friction Controller for Linear Structures against Earthquakes

Semiactive friction dampers (SAFD) have been shown to be more effective than passive friction dampers in reducing structural response due to earthquakes. The effectiveness of SAFD, however, depends on the control strategy used. Because of the nonlinear nature of friction dampers, the establishment of an effective control strategy is a challenging effort. The motion of friction dampers, either passive or semiactive, involves sticking and slipping phases. The idea for increasing the performance of SAFD is to maintain its motion in the slipping phase as much as possible, as energy is dissipated during the slipping phase rather than the sticking phase. In this paper, the authors propose control strategies which are capable of: 1) maintaining the motion of SAFD in the slipping phase as much as possible; and 2) eliminating the undesirable acceleration spikes by introducing an appropriate boundary layer in the control strategy. Two structures, a 6-story base-isolated structure and a 3-story fixed base building model, were used to demonstrate the performance of the proposed control strategies using different far-field and near-field earthquakes. Further, the performances of various combinations of passive and semiactive energy dissipation devices have been evaluated and compared. Based on numerical simulation results, it is demonstrated that the proposed semiactive friction control strategies are very effective.
Implications of iodine‐xenon studies for the timing and location of secondary alteration

— Iodine-xenon ages (based on 15.7 Ma 129I) of meteoritic samples are highly susceptible to secondary alteration processes, so they have the potential to determine both the timing, and in some cases the location, of those secondary processes. Iodine-xenon studies can determine the location in two cases. First, if the length of time required is greater than the lifetime of the nebula, then the process must have occurred on a parent body. Ages from sodalite in Allende, dark inclusions in Efremovka (CV3), and some samples from CM chondrites all suggest durations of several million years, in some cases marginally longer than the predicted duration of the nebula. Second, in some cases the evolution of the 129Xe/132Xe ratio can be used to determine the I/Xe elemental ratio of the reservoir in which the evolution occurred. For chondrules from the unequilibrated ordinary chondrites Chainpur and Tieschitz, the isotopic evolution is quantitatively consistent with evolution in a chondritic (parent body), rather than nebular, reservoir.
Fluctuating hyperfine interactions: an updated computational implementation

The stochastic hyperfine interactions modeling library (SHIML) is a set of routines written in the C programming language designed to assist in the analysis of stochastic models of hyperfine interactions. The routines read a text-file description of the model, set up the Blume matrix, upon which the evolution operator of the quantum mechanical system depends, and calculate the eigenvalues and eigenvectors of the Blume matrix, from which theoretical spectra of experimental techniques can be calculated. The original version of SHIML constructs Blume matrices applicable for methods that measure hyperfine interactions with only a single nuclear spin state. In this paper, we report an extension of the library to provide support for methods such as Mossbauer spectroscopy and nuclear resonant scattering of synchrotron radiation, which are sensitive to interactions with two nuclear spin states. Examples will be presented that illustrate the use of this extension of SHIML to generate Mossbauer spectra for polycrystalline samples under a number of fluctuating hyperfine field models.