cssi/SciSciGPT-SciSciNet huggingface dataset:
Polarization discrimination technique to maximize LIDAR signal to noise ratio

Range and sensitivities of lidar measurements are limited in daytime use by sky background noise (BGN). We report on a polarization technique to reduce the detected sky BGN by making use of the fact that daylight sky noise is polarized by atmospheric scattering to a greater or lesser degree, depending on the solar zenith angle. With suitable rotation of a beam polarizer at the entrance of the detector, the sky noise reaching the detector is minimized. At the same time, the polarization of the outgoing lidar signal is rotated to align the polarizations of both the outgoing and elastically scattered return signals with that of the polarizer in front of the detector. This ensures unhindered passage of lidar returns to the detector while at the same time minimizing detected BGN. Daylight measurements with a vertically oriented elastic backscatter lidar at 532 nanometers show that as much as tenfold improvements in signal to noise ratio (SNR), and consequent improvements in effective lidar range, can be obtained for high solar zenith angles (less for angles closer to the zenith) in typical urban atmospheric conditions. The variations in SNR as a function of different solar angles were found to be consistent with theoretical estimates of the variation of the polarization factor for incoming vertical skylight for an urban atmosphere based on adjacent CIMEL measurements of the atmospheric optical depth over the same period.
Formal semantics for rule-based systems

Abstract The existence of a formal description of any language is a prerequisite to any rigorous methods of proof, validation, or verification. This article develops a formal semantics in the denotational style for rule-based production systems. Primarily, a formal description of a generalized, hypothetical language for rule-based expert systems is developed as a base. Building on this base, it is possible to specify in detail the variations that distinguish individual real-world systems in a usable way.
Trend and variation of prescription drug cost in the veterans health-care system

Using descriptive statistics, this paper revealed that the prescription drug cost as a percentage of total health-care cost in Department of Veterans Affairs (VA) health-care system has outpaced the national trend. Given the fact that the national drug expenditure is the most fast-growing component in the health-care expenditure, the drug cost trend in VA commands further assessment for its financial and clinical impact. Furthermore, by applying simple log linear regression, we analysed the geographic variation in prescription drug use in the VA health-care system. We found a 30% deviation from the predicted drug cost at medical centre level and 15% deviation at Network level. Although this variation is relatively small compared with the variation in other medical service use, reduction of the variation has significant clinical and financial implications. Since the method used in this study is easy to implement, this paper provides a practical tool for large health-care systems such as VA, States and health maintenance organizations to identify those hospitals that over- or under-prescribe drugs.
Hyperlexia in Infantile Autism

Twenty boys meeting the current DSM III criteria for infantile autism at the time of diagnosis were found to be hyperlexic in childhood and have been followed up for 7–17 years. The most striking feature of the group was the compulsion to decode written material without comprehension of its meaning, and this constituted a behavioral phenotype for this population. On word recognition tests such as the WRAT, they scored significantly higher than would be predicted on the basis of intelligence but demonstrated severe reading retardation on tests of reading comprehension such as the Gates-McGinitie. Major differences in intelligence were detected, ranging from severe mental retardation to very superior intelligence. Major differences in verbal and nonverbal abilities were also noted. Many were found to have unusually good memory, both visual and auditory, and the majority possessed an excellent stored vocabulary that could be used with written words despite the poverty of their expressive language. It is suggested that the presence of hyperlexia may identify a subgroup of autistic children.
INTERFACE DISLOCATIONS AND LEDGES IN OXIDATION AND DIFFUSIONAL PHASE TRANSFORMATIONS

The origin of ledge concepts in growth from the vapor is reviewed. The ideas are extended to solid-state phase transformations with the added effects of strain and misorientation. Types of ledges and dislocations are classified. The concepts are illustrated for the example of oxidation of a metal. Further extensions to diffusional phase transformations are briefly discussed.
The Rodent Carcinogenicity Bioassay Produces a Similar Frequency of Tumor Increases and Decreases: Implications for Risk Assessment

We examined the overall results of 124 consecutive rodent carcinogenesis assays carried out at the maximum tolerated dose on 37 chemicals reported recently by the Toxicology Program of the United States. In 31 experiments each in male and female F-344 rats and in male and female B6C3F1 mice, tumor increases and decreases occurred in 41 and 46% of the experiments, respectively. In 22 experiments both increases and decreases in tumor incidence were reported. Of the experiments with decreases in tumor incidence, about 70% were associated with lower body weights of the treated animals. However, of the 30 chemicals producing some tumor decreases, 12 showed decreases in some experiments without any association with bodyweight. Ten chemicals that were Salmonella positive produced increases and decreases in tumor incidences and three produced only decreases in tumor incidence. If it is considered that the bioassay provides information relevant to the carcinogenic potential of a chemical, then logically it must also be considered that information about the cancer-preventive potential of a chemical is provided. When a chemical causes increases and decreases in tumors, several questions follow. First, which are more relevant to the health of an exposed individual: tumor increases or tumor decreases? Second, should such a chemical be stigmatized as a "carcinogen," in view of all the legal and economic implications that ensue from such a label? Third, how should one define a carcinogen?
Toward an Objective Characterization of an Anhedonic Phenotype: A Signal-Detection Approach

Background Difficulties in defining and characterizing phenotypes has hindered progress in psychiatric genetics and clinical neuroscience. Decreased approach-related behavior and anhedonia (lack of responsiveness to pleasure) are considered cardinal features of depression, but few studies have used laboratory-based measures to objectively characterize these constructs. Methods To assess hedonic capacity in relation to depressive, particularly anhedonic, symptoms, 62 participants completed a signal-detection task based on a differential reinforcement schedule. Anhedonia was operationalized as decreased reward responsiveness. Results Unequal frequency of reward between two correct responses produced a response bias (i.e., a systematic preference to identify the stimulus paired with the more frequent reward). Subjects with elevated depressive symptoms (Beck Depression Inventory scores ≥ 16) failed to show a response bias. Impaired reward responsiveness predicted higher anhedonic symptoms 1 month later, after controlling for general negative affectivity. Conclusions Impaired tendency to modulate behavior as a function of prior reinforcement might underline diminished hedonic capacity in depression. When applied to a clinical population, objective assessments of participants’ propensity to modulate behavior as a function of reward might provide a powerful tool for improving the phenotypic definition of depression and thus offer a reliable behavioral screening approach for neuroscience studies of depression.
Modeling, Comparison and Analysis of Multi-body Parafoil Models with Varying Degrees of Freedom

Guided parafoils are comprised of two primary bodies, a payload and parafoil. While the parafoil generates the majority of aerodynamic loads, the sensor systems used for guidance are located away from the parafoil near the payload. In this paper, miniature wireless sensors are embedded in the canopy and payload during flight and used to measure the parafoil-payload relative motion. Experimental data is compared to models ranging from six to nine degrees-of-freedom. Each model can be justified by different connection configurations; however, in each case the ideal configurations are only approximately satisfied. As a primary example, a six degree-of-freedom model assumes the payload and canopy are rigidly connected while actual systems will have relative payload-canopy motion. In practical applications, it is desirable to model the system with the minimum degrees-of-freedom while capturing all significant dynamics. This paper compares the model configurations with experimental data and shows which models are most appropriate under varying conditions.
Statistical inference of minimum BD estimators and classifiers for varying-dimensional models

Stochastic modeling for large-scale datasets usually involves a varying-dimensional model space. This paper investigates the asymptotic properties, when the number of parameters grows with the available sample size, of the minimum-BD estimators and classifiers under a broad and important class of Bregman divergence (BD), which encompasses nearly all of the commonly used loss functions in the regression analysis, classification procedures and machine learning literature. Unlike the maximum likelihood estimators which require the joint likelihood of observations, the minimum-BD estimators are useful for a range of models where the joint likelihood is unavailable or incomplete. Statistical inference tools developed for the class of large dimensional minimum-BD estimators and related classifiers are evaluated via simulation studies, and are illustrated by analysis of a real dataset.
Paper 12: Product Development Aspects of Motor Vehicle Testing

Vehicle testing is seen to have the dual purpose of ensuring customer satisfaction and increasing engineering design experience and knowledge.The techniques used vary in accordance with the objectives of the investigation. Research and development test methods are designed to assess the achievement of product performance objectives and to provide information to guide engineering design.Specific examples of tests, instrumentation and analysis used in relation to vehicle durability, noise, ride and handling, heating and ventilating systems, and engine cooling systems are included. Importance of overseas testing to evaluate vehicle behaviour in various environments is stressed.Production validation testing of vehicles built by production methods, prior to new model introduction date, is designed to ensure that performance specifications, vehicle reliability and quality targets are satisfied.Quality control testing is designed to ensure that product objectives are maintained. Test methods are simple and resul...
Minimizing the expected flowtime in stochastic flow shops

Abstract In this paper we consider a flow shop with blocking, n jobs, m machines, and stochastic processing times. We show that if the jobs can be stochastically ordered, then a SEPT sequence minimizes the expected flowtime on two machines.
The spectral sensitivity and flicker response of the eye of the stomatopod, Squilla empusa say☆

Abstract 1. 1. The bilobed eyes of Squilla empusa were found by electroretinogram measurement to have a single retinal pigment with a λmax of 520 nm. Neither blue nor red light adaptation shifted the curve. This is indicative of a visual system that is incapable of color vision. 2. 2. Both the λmax and the ERG wave forms were found to be identical for the two lobes of the eye. 3. 3. The process of dark adaptation is complex and long term. Generally the eye shows a peak sensitivity near midnight when the animals are on an 11–13 light-dark photoperiod. 4. 4. The flicker fusion frequency of the eye is dependent on the state of light adaptation as in other eyes, and an unusually high value of fusion is reached at 125/sec when I = 1660 μW/cm2.
The Moment as a Factor in Emotional Well-Being

The moment is a phenomenon of increasing interest to observers of human experience, whether their concern be literature, art, theology, psychology, history, or sports. For in the moment an individual's sense of reality is heightened and his capacity for choice is intensified. Among the situations where our sense of reality can both reflect and produce a significant level of emotional well-being are moments where presentness is keenly felt, interpersonal relationships, kinetic experiences in sports, the sense of being inspired, moments of commitment, highly dramatic presentations of the self, and peak experiences. The literature is extensive.
Synthesis of epitaxial 3C-SiC by C60 carbonization of silicon on sapphire

Abstract C 60 molecule deposition onto commercial SOS (silicon on sapphire) wafers with (001) silicon on r-plane (1102) sapphire results in the formation of silicon carbide (SiC), if substrate temperatures of 810 °C are exceeded. Elastic recoil spectroscopy indicates the formation of a stoichiometric SiC layer. X-ray pole figure measurements show that the main part of the resulting cubic 3C-SiC grows epitaxially with the underlaying silicon. Cross-sectional transmission electron microscopic investigations indicate as well that the 3C-SiC exhibits an epitaxial relationship to the Si matrix and that the resulting SiC grains grow columnarly.
Emerging pollutants, and communicating the science of environmental chemistry and mass spectrometry: pharmaceuticals in the environment

While this paper is to a large degree targeted for those not familiar with mass spectrometry, [for an overview of mass spectrometry, a number of excellent websites are available, including http://base-peak.wiley.com/links/Resources/Educational_Resources], the primary focus is on the importance of mass spectrometry in ultimately protecting public health and minimizing risks of chemical exposure. Its other audience is those who practice in this specialized field. Should this subject not interest you, by reading this article you can discover among other things, why elevator rides can be important for your career and for your discipline. Why acetaminophen is used for brown tree snakes, or lipid-lowering drugs for pigeons.
Effect of the Immunomodulator Tilorone on Antipyrine Disposition in the Rat

A wide variety of immunomodulators, including the synthetic interferon inducer tilorone (2, 7-bis[2-(diethylamino)ethoxy]fluoren-9-one), have been shown to inhibit cytochrome P-450-dependent drug metabolism in vitro. In an effort to determine if tilorone also inhibits drug metabolism in vivo, we examined the effect of this agent on the disposition of antipyrine in the rat. Administration of tilorone hydrochloride (50 mg-kg−1.d−1) for 4 d resulted in a 42% reduction in antipyrine clearance and a 71% increase in plasma half-life. Administration of a single dose of tilorone hydrochloride (50 mg/kg) 48 h prior to antipyrine was found to cause a similar alteration in antipyrine clearance and half-life. Both treatment regimens were also found to produce a substantial weight loss in the pretreated animals. Preliminary studies indicated that tilorone treatment reduced food and water consumption in the rat. Therefore, the effect of a 75% decrease in food and water consumption on antipyrine disposition was also examined. This magnitude of restriction had no detectable effect on antipyrine elimination. Thus, tilorone results in a substantial reduction of the in vivo metabolic clearance of antipyrine and appears to be a useful compound for studying the dynamic interaction between the drug metabolizing and immune systems in vivo.
Clashes within one teacher’s racial logic: space of possibles?

This study is to empirically investigate both residual and emergent factors that undergird one teacher’s understanding of race, racism, and racialization as he responds to two fictional stories and one film. Informed by an assemblage of Bourdieu’s concept of habitus and his sociological theory of practice, Gee’s concept of primary Discourses, and Omi and Winant’s theory of racial formation, the research questions are as follows: How are the concepts of race, racism, and racialization understood by one teacher? What are the factors that shape this teacher’s perceptions of race, racism, and racialization? What social and institutional dimensions are imbedded in these constitutive factors? What are the consequences of his understandings of race, racism, and racialization with respect to working productively with students from historically racially marginalized groups? Are there any patterns and/or oppositions among his perceptions of race, racism, and racialization, and what do those patterns and oppositions...
Interstellar depletion anomalies and ionization potentials

Satellite observations indicate that (1) most elements are depleted from the gas phase when compared to cosmic abundances, (2) some elements are several orders of magnitude more depleted than others, and (3) these depletions vary from cloud to cloud. Since the most likely possibility is that the ‘missing’ atoms are locked into grains, depletions occur either by accretion onto core particles in interstellar clouds or earlier, during the period of primary grain formation. If the latter mechanism is dominant, then the most important depletion parameter is the condensation temperature of the elements and their various compounds. However, this alone is not sufficient to explain all the observed anomalies. It is shown that electrostatic effects—under a wide variety of conditions—can enormously enhance the capture cross-section of the grain. It is suggested that this mechanism can also account for such anomalies as the apparent ‘overabundance’ of the alkali metals in the gas phase.
Furans in Synthesis. The Preparation of (±)-Lactaral

Abstract The Functionalized Grignard reagent 13 reacts with allylic chloride 14 , in the presence of Li 2 CuCl 4 , to provide lactarol-THP ether 15a which is subsequently converted to (±)-lactaral 5 in 72% overall yield from 13 .
Receptor Heteromerization Expands the Repertoire of Cannabinoid Signaling in Rodent Neurons

A fundamental question in G protein coupled receptor biology is how a single ligand acting at a specific receptor is able to induce a range of signaling that results in a variety of physiological responses. We focused on Type 1 cannabinoid receptor (CB1R) as a model GPCR involved in a variety of processes spanning from analgesia and euphoria to neuronal development, survival and differentiation. We examined receptor dimerization as a possible mechanism underlying expanded signaling responses by a single ligand and focused on interactions between CB1R and delta opioid receptor (DOR). Using co-immunoprecipitation assays as well as analysis of changes in receptor subcellular localization upon co-expression, we show that CB1R and DOR form receptor heteromers. We find that heteromerization affects receptor signaling since the potency of the CB1R ligand to stimulate G-protein activity is increased in the absence of DOR, suggesting that the decrease in CB1R activity in the presence of DOR could, at least in part, be due to heteromerization. We also find that the decrease in activity is associated with enhanced PLC-dependent recruitment of arrestin3 to the CB1R-DOR complex, suggesting that interaction with DOR enhances arrestin-mediated CB1R desensitization. Additionally, presence of DOR facilitates signaling via a new CB1R-mediated anti-apoptotic pathway leading to enhanced neuronal survival. Taken together, these results support a role for CB1R-DOR heteromerization in diversification of endocannabinoid signaling and highlight the importance of heteromer-directed signal trafficking in enhancing the repertoire of GPCR signaling.
Additional rules for the transformed up-down method in psychophysics

In a classic paper, Levitt (1971) described an adaptive procedure for estimating points on the psychometric function known as thetransformed up-down method. Levitt discussed the assumptions of the method and presented a brief table with simple rules that converge to a few different points on the psychometric function. Levitt’s original table contains only the simplest rules, and sparsely covers the range of the psychometric function. This paper provides a table with previously unpublished rules which cover the range of the psychometric function at 5% intervals. There is a brief review of the major issues in adaptive testing. Technical issues such as the mean length and logical construction of the new rules are discussed.
The Effect of Curing on Drug Release and Morphological Properties of Ethylcellulose Pseudolatex-Coated Beads

AbstractDrug-containing nonpareil beads were coated in a fluidized bed with a commercial ethylcellulose pseudolatex, Aquacoat. The drug release was investigated as a function of curing conditions (curing time and temperature) for a hydrophilic and lipophilic drug (chlorpheniramine maleate and ibuprofen) at different levels of plasticizer (triethyl citrate). Curing of coated beads at elevated temperatures immediately after the coating process significantly changed the drug release pattern. Both a retardation and an enhancement in drug release were seen, with the extent being dependent on the type of drug and curing conditions. With chlorpheniramine maleate, a drug with low affinity for the ethylcellulose coating, a curing step was necessary at intermediate plasticizer levels to obtain good film formation and a limiting drug release pattern, while the use of higher plasticizer levels eliminated the need for a curing step. With ibuprofen, a lipophilic drug with high solubility in the ethylcellulose coating, ...
Discriminative validity of the behavior assessment system for children‐parent rating scales in children with recurrent abdominal pain and matched controls

Examined discriminative validity of the Parent Rating Scale (PRS) of the Behavior Assessment System for Children (BASC; Reynolds & Kamphaus, 1992, Circle Pines, MN: American Guidance Services). Two groups were compared: a cohort with recurrent abdominal pain (RAP) (n= 49) and children from the BASC-PRS standardization sample (n = 49) matched on the background characteristics of age, race/ethnicity, and gender. A multivariate, two-group discriminant function analysis was used to compare groups across standard scores from the nine clinical scales of the PRS. Results demonstrated that children with RAP could be differentiated (Wilks λ = .642, F = 6.45, df (9, 88), p < .001), and demonstrated higher scores on the Somatization, Depression, Anxiety, Attention Problems, and Withdrawal scales. Subsequent jackknifed classification analysis, diagnostic efficiency statistics, and an odds ratio for the classification analysis added to the overall validity of results. The practical utility of the BASC-PRS is further supported in light of expanding roles for school psychologists in the assessment and treatment of children with health problems. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 145–154, 2003.
Proposed workflow for improved Kauth–Thomas transform derivations

Abstract The Kauth–Thomas (K–T) transform, also known as the Tasseled-Cap (T-C) transform, is a widely used metric capable of capturing scene characteristics in related coordinate directions in a defined feature space. There is a perceived apprehension to use the transform because the derivation methods are diverse, and concern that coefficients are only useful for the images from which they were derived. We address these concerns and outline a workflow for future derivations. First, we ensure greater consistency of future K–T transform derivations by creating an empirical approach to identify scenes most favorable for derivations. This approach can be applied to large data archives and provide a “first-cut” criterion for selecting vegetation land cover dominated scenes. The algorithm provides a quantified basis to exclude imagery from a K–T transform derivation because of ill-suited land cover. This empirically derived relationship can be used to sort large imagery archives for vegetation land cover dominated scenes. This “first-cut” method still requires the need for an analyst, but the work load is greatly reduced. Each K–T transform matrix is sensor and data-model specific. For every sensor and data type (e.g., radiance, reflectance, DN), a new transform matrix must be derived. As an example of using the work flow we derive the DN-based Landsat 7 ETM + K–T transform coefficients and show the resulting tasseled-cap space. The proposed process uses the first two dominant eigenvalues which are the roots of the characteristic equations solving the variance–covariance matrix of the spectral data. We have discovered that these quantities are discriminative of the land cover type contained in the scene. Not only can these specific types eigenvalues be used to select appropriate scenes for the K–T transform derivation but can also be included in the image header as a useful parameter in imagery database inquiries. Like cloud cover and image quality flags, the ln-lambda1 [ln(λ1)] and ln-lambda2 [ln(λ2)] values provide general information about the variability and land cover of the scene.
Combinatorial and experimental results for randomized point matching algorithms

Abstract The subject of this paper is the design and analysis of Monte Carlo algorithms for two basic matching techniques used in model-based recognition: alignment, and geometric hashing. We first give analyses of our Monte Carlo algorithms, showing that they are asymptotically faster than their deterministic counterparts while allowing failure probabilities that are provably very small. We then describe experimental results that bear out this speed-up, suggesting that randomization results in significant improvements in running time. Our theoretical analyses are not the best possible; as a step to remedying this we define a combinatorial measure of self-similarity for point sets, and give an example of its power.
Proopiomelanocortin-derived peptides and mRNA are expressed in rat heart.

Proopiomelanocortin (POMC) is posttranslationally processed to a-MSH, p-endorphin, and a variety of other peptides, not only in the pituitary and brain, but in peripheral tissues as well. P-Endorphin and its immediate precursor p-lipotropin (P-LPH) have recently been identified in cardiac tissue' suggesting that the POMC gene is expressed in heart, although neither the cellular localization nor the posttranslational processing of cardiac POMC peptides has been fully characterized. The localization of p-endorphin, as well as other opioid peptides, in cardiac tissue is consistent with extensive evidence that opiates produce direct effects on cardiac function, reducing cardiac output, coronary pressure, and heart rate.2s3 ACTH, a-MSH, and related ACTH fragments also exhibit potent, albeit opposing, cardioregulatory activities, increasing heart rate and ~ont rac t i l i ty ,~ ,~ although their biosynthesis in cardiac tissue has not, as yet, been demonstrated. In the present study, we further characterized POMC processing in rat heart and also showed, using in situ hybridization, that POMC mRNA is localized within cardiac ventricular muscle cells. Initial gel filtration high-performance liquid chromatography (HPLC) analysis revealed that immunoreactive ACTH and a-MSH are both present in rat heart extracts; however, ACTH levels are quite low relative to a-MSH concentrations (s5%), suggesting that ACTH is almost entirely converted to a-MSH. Reverse phase HPLC further demonstrated that the principal a-MSH-related peptides in heart are a-MSH and N,O-diacetyl-a-MSH; des-acetyl-a-MSH is a relatively minor constituent (FIGURE l). Similarly, sequential gel filtration and cation exchange HPLC analysis indicated that p-LPH is almost entirely converted to p-endorphin and that P-endorphin-1-3 1 is further modified through both N-acetylation and C-terminal proteolysis (FIGURE 1). N-Acetyl-P-endorphin-( 1-31) is the predomi-
The Variable Response of Normal Chicks to Stress Rations and a Vitamin B12 Supplement

Abstract CHICKS from dams fed balanced rations containing adequate amounts of vitamin B12 have demonstrated consistently a desirable carry-over effect of the vitamin resulting in superior livability and growth. In many studies this effect should be eliminated when early chick growth is used in studies involving vitamin B12. Elimination of this effect has been accomplished by using chicks from dams on a vitamin B12 deficient ration and/or by using stress rations for chicks from normal dams. The term “stress ration” has been used either to indicate a ration that will deplete the chick more rapidly than a balanced ration deficient only in the vitamin studied or to indicate a ration that will increase the chick’s requirement for the factor. Rubin and Bird (1947) and Bird et al. (1948) developed a high protein stress ration containing 70 percent soybean oil meal to be used in a short assay procedure for studying the …
THE PROBABILITY DISTRIBUTION FOR A RANDOM MATCH BETWEEN AN EXPERIMENTAL-THEORETICAL SPECTRAL PAIR IN TANDEM MASS SPECTROMETRY

Proteomic techniques are fast becoming the main method for qualitative and quantitative determination of the protein content in biological systems. Despite notable advances, efficient and accurate analysis of high throughput proteomic data generated by mass spectrometers remains one of the major stumbling blocks in the protein identification problem. We present a model for the number of random matches between an experimental MS-MS spectrum and a theoretical spectrum of a peptide. The shape of the probability distribution is a function of the experimental accuracy, the number of peaks in the experimental spectrum, the length of the interval over which the peaks are distributed, and the number of theoretical spectral peaks in this interval. Based on this probability distribution, a goodness-of-fit tool can be used to yield fast and accurate scoring schemes for peptide identification through database search. In this paper, we describe one possible implementation of such a method and compare the performance of the resulting scoring function with that of SEQUEST. In terms of speed, our algorithm is roughly two orders of magnitude faster than the SEQUEST program, and its accuracy of peptide identification compares favorably to that of SEQUEST. Moreover, our algorithm does not use information related to the intensities of the peaks.
Mammalian collagenase increases in early alcoholic liver disease and decreases with cirrhosis.

Abstract To determine if alterations in collagen degradation may contribute to the pathogenesis of fibrosis and cirrhosis, we studied the hepatic collagenase activity of 20 baboons given alcohol containing diets or control diets under carefully controlled experimental conditions. We also studied 28 patients whose livers were biopsied for diagnostic purposes. Hepatic collagenase activity was significantly increased in baboons with fatty liver compared to levels in normal, control fed animals [(1.98±0.19 vs 1.20±0.08 units ( μ g collagen digested/ hour/mg liver protein) ± S.E.M., p s 0.001). A single cirrhotic baboon available for study had an hepatic collagenase activity of 1.58 units. Patients with hepatic fibrosis had significantly higher hepatic collagenase activity than those with fatty livers [(9.12±0.94 (n=14) vs 4.52±0.54 (n=7) units±S.E.M., p Our findings suggest that the development of cirrhosis is coincident with, or favored by a failure of hepatic collagen degradative enzymes to keep pace with hepatic collagen synthesis.
Improved bounds for high dimensional cone multipliers

We obtain some improved bounds for high dimensional cone multipliers by combining the well-known L 2 cone restriction estimate with a refined Calderon-Zygmund decomposition which comes under the consideration of the support of the kernel.
Examining the Tasks of Teaching When Using Students' Mathematical Thinking

Recent research suggests that the examination of students' work may lead to changes in teaching practice that are more effective in terms of students' mathematical learning. However, the link between the examination of students' work and the teachers' actions in the classroom is largely unexamined, particularly at the secondary level. In this paper, I present the results of a study in which teachers had extensive opportunities to examine the development of students' conceptual models of exponential growth in the context of their own classrooms. I describe two related aspects of the practice of one teacher: (a) how she listened to students' alternative solution strategies and (b) how she responded to these strategies in her practice. The results of the analysis suggest that as the teacher listened to her students, she developed a sophisticated schema for understanding the diversity of student thinking. The actions of the teacher supported extensive student engagement with the task and led the students to revise and refine their own mathematical thinking. This latter action reflects a significant shift in classroom practice from the role of the teacher as evaluator of student ideas to the role of students as self-evaluators of their emerging ideas.
Pulse compression at an abrupt dispersive interface

Reflection from the interface of a dielectric and a resonant medium we show can result in pulse narrowing and multiplication. Results are given for an asymmetric Fourier transform-limited pulse, and possible experimental situations are discussed. Using pulses from a colliding pulse mode-locking scheme, low-level pulses as short as 15 fsec may be achievable.
A numerical model of stress driven grain boundary diffusion

The stress driven grain boundary diffusion problem is a continuum model of mass transport phenomena in microelectronic circuits due to high current densities (electromigration) and gradients in normal stress along grain boundaries. The model involves coupling many different equations and phenomena, and difficulties such as nonlocality, stiffness, complex geometry, and singularities in the stress tensor near corners and junctions make the problem difficult to analyze rigorously and simulate numerically. We present a new numerical approach to this problem using techniques from semigroup theory to represent the solution. The generator of this semigroup is the composition of a type of Dirichlet to Neumann map on the grain boundary network with the Laplace operator on the network. To compute the former, we solve the equations of linear elasticity several times, once for each basis function on the grain boundary. We resolve singularities in the stress field near corners and junctions by adjoining special singular basis functions to both finite element spaces (2d for elasticity, 1d for grain boundary functions). We develop data structures to handle jump discontinuities in displacement across grain boundaries, singularities in the stress field, complicated boundary conditions at junctions and interfaces, and the lack of a natural ordering for the nodes on a branching grain boundary network. The method is used to study grain boundary diffusion for several geometries.
Position Estimation Using Only Multiple Simultaneous Range Measurements

Three-dimensional generalized position-measurement systems are analyzed in this paper. In these systems, target position is obtained by trilateration using only range data collected by a group of v stations located in an arbitrary geometry. The method of maximum likelihood is used to obtain a joint estimator for the target coordinates which makes optimal use of the redundant data when the noise is Gaussian. A simple recursion formula for the estimator is obtained for this purpose and is shown to be convergent. This formula makes it possible to add data from a redundant number of stations at will and in proportion to their relative reliability. Further, it is shown that the recursion formula can be written entirely in terms of the changes in the successive iterative target position estimates. This technique offers a new means of obtaining tracking data on a moving target since it permits changes in target position to be computed directly as new data are obtained. The covariance matrix of the joint three-dimensional estimator is obtained in the case in which the measurement noise is small compared to the distances measured. The mean-square position error, namely, the trace of the covariance matrix, is shown to have a simple form for the general two-dimensional system in which the target and stations are coplanar. The geometry enters the variance expression only through the angles of cut ?if, which are the angles between the lines joining the target and the stations.
A comparative trial of psychotherapy and pharmacotherapy for “pure” dysthymic patients

Abstract Background Psychotherapy of “pure” dysthymic disorder remains understudied. This article reports outcomes of an acute randomized trial of 94 subjects treated for 16 weeks with either interpersonal psychotherapy (IPT), brief supportive psychotherapy (BSP), sertraline, or sertraline plus IPT. Methods Recruited by clinical referral and advertising, subjects met DSM-IV criteria for early onset dysthymic disorder, with no episode of major depression in the prior six months. They were randomly assigned to one of four 16-week treatments, with options for crossover or continuation treatment. Results were analyzed from the intention-to-treat sample by ANCOVA, controlling for baseline depressive severity. Results Subjects improved in all conditions over time, with the cells including sertraline pharmacotherapy showing superiority over psychotherapy alone for response and remission. Response rates were 58% for sertraline alone, 57% for combined treatment, 35% for IPT, and 31% for BSP. Limitations The study was underpowered and may have employed too “active” a control condition. Follow-up data were unobtainable. Conclusions In this acute trial for “pure” dysthymic disorder, sertraline with or without IPT showed advantages relative to IPT and BSP. Methodological difficulties may have limited differential outcome findings. This study bolsters a small but growing literature on the treatment of dysthymic disorder, suggesting that pharmacotherapy may acutely benefit patients more than psychotherapy.
Dual-transduction-mode sensing approach for chemical detection

Abstract Smart devices such as electronic nose have been developed for application in many fields like national security, defense, environmental regulation, health care, pipeline monitoring and food analysis. Despite a large array of individual sensors, the resolving power of these devices can still be improved to identify a target at a very low concentration out of a mixture of odors, if different types of transductions are employed in concert as a set of sensing responses to distinguish one odor from another. Here, we propose a new sensor architecture enabling different types of transduction signals in parallel on the same individual sensor. We demonstrate this architecture using a light emitting organic field-effect transistor (LEOFET) operated at a dual-transduction mode, as a proof-of-concept. Sensing response has been observed on both electrical and optical output signals from a green LEOFET upon exposure to an explosive taggant, with optical signal exhibiting much higher sensitivity. This new sensor architecture opens a field of devices of synergic capabilities to distinguish chemical and biological targets.
Identification of a stanniocalcin paralog, stanniocalcin-2, in fish and the paracrine actions of stanniocalcin-2 in the mammalian ovary.

Stanniocalcin is a glycoprotein hormone important in the maintenance of calcium and phosphate homeostasis in fish. Two related mammalian stanniocalcin genes, STC1 and STC2, were found to be expressed in various tissues as paracrine regulators. We have demonstrated the existence of a second stanniocalcin gene in fish, designated fish STC2, with only 30% identity to fish STC1. However, phylogenetic analysis and comparison of the genomic structure of STC genes in vertebrates indicated that STC1 and STC2 genes were probably derived from a common ancestor gene. Based on the prominent expression of mammalian STC1 in the ovary, we tested STC2 expression in rat ovary and the regulation of STC2 expression by gonadotropins. Treatment of immature rats with pregnant mare serum gonadotropin increased STC2 transcripts, whereas subsequent treatment with human chorionic gonadotropin suppressed STC2 expression. Real-time PCR analyses also demonstrated that STC2 is expressed mainly in thecal layers. In situ hybridization s...
The amount of galactose genetic material in λdg bacteriophage with different densities

Previous work has shown that the buoyant density of different λdg phages varies widely. We aimed to find out if there are any λdg phages that carry only a part of the gal operon (i.e. the genes for galactokinase, transferase and epimerase), and if there is any relation between the density of a λdg phage and the amount of gal operon it carries. No matter what the density of the phage, most λdg in a low frequency transducing lysate were found to contain the entire set of three genes for galactose metabolism. However, about 10% of the λdg phages were found to have deletions in this set of genes. These defects are all in the galactokinase gene and range from a small deletion to the deletion of practically the entire galactokinase gene. The deletions all begin at one end of the galactokinase gene. For several of the λdg with gal deletions, the size of the λ deletion was determined by Dr. Allan Campbell. There is no relation between the size of the λ deletion and the size of the gal deletion. The density of a λdg phage appears to be determined by the size of its λ deletion and by the amount of the bacterial gal operon incorporated.
Prophylactic ibuprofen administration during pelvic irradiation

Abstract Thirty-five patients who were to begin pelvic irradiation for malignant disease were randomized to receive ibuprofen 400 mg P.O. q.i.d. during their radiotherapy or standard therapy for radiation-induced gastroin testinal symptoms. Seventeen of 19 patients in the ibuprofen group completed the protocol. There was no significant difference in the daily stool frequency between the ibuprofen and control patients during the 5–6 week course of pelvic irradiation; the incidence and severity of diarrhea was the same. There was no significant difference in the incidence of nausea reported by the patients but the severity of nausea was less in the ibuprofen group; none of the 17 patients in the ibuprofen group reported vomiting at any time, whereas, 27% of the patients in the control group reported vomiting. The difference was statistically significant ( p
Alprazolam-reinforced medication use in outpatients with anxiety

The reinforcing effects of alprazolam were investigated in 14 patients who had generalized anxiety or panic disorder, but were not current users/abusers of other psychoactive substances. Using a double-blind outpatient choice procedure, color-coded alprazolam (0.5 mg) and placebo capsules were provided to patients for use 'as needed' in the treatment of anxiety symptoms. Comparisons of alprazolam and placebo during a 2 week sampling period in which placebo and alprazolam were available sequentially revealed no significant differences on measures of medication usage or anxiety levels, although alprazolam did increase subjective ratings of drug effects side effects. During a 4 week choice period, alprazolam was strongly preferred over placebo in 11 out of 14 patients indicating that alprazolam functioned as a reinforcer. Medication usage ranged from zero to 4.0 mg alprazolam in a day. Variations in daily medication-use were positively correlated with anxiety level fluctuations for a majority of patients. For a majority of patients, the results indicate that alprazolam functioned as a reinforcer without accompanying signs of abuse or addiction.
“Daunting” task of assembling data for a geospace global circulation model begins

This is the second article in a series of three on the Geospace Environment Modeling program. The first article, “Milestones in Geospace Environment Modeling,” appeared in the December 28, 1993, issue of Eos. The Geospace Environment Modeling (GEM) Program is quickly moving toward a general circulation model (GCM) for geospace similar to the powerful GCMs that now support troposphere-stratosphere and thermosphere-ionosphere research. Since, according to Richard Feynman, “the test of a science is its ability to predict,” the geospace GCM (GGCM) holds the key to validating magnetospheric science, unifying its researchers, and demonstrating the mastery of the field to other geophysicists.
Changes in the environmental pollution in the Calcutta‐Hooghlyside industrial strip of India

Changes in the environmental perception of people of the Calcutta‐Hooghlyside industrial belt are discussed. Residents of the area are becoming increasingly aware of air and water pollution. A positive correlation exists between the frequency of their perception of air and water pollution problems and the actual level of pollution in the area.
The Effect of Organic Material and Inorganic Ions on the Photosynthetic Rate of the Red Alga Bostrychia binderi from a Florida Estuary

Various constituents of spring water (calcium, bicarbonate, nitrate, phosphate, total organic material) influence the response of photosynthetic rate of Bostrychia binderi Harvey to changes in salinity. The rate of photosynthesis increased with a decrease in salinity. The rate of photosynthesis in low salinities was greater in seawater diluted with spring water than in sewater diluted with distilled water. Elevation of photosynthetic rates in the lower salinities (0 and 5 ppt) was partially due to increased levels of bicarbonate and various nutrients present in natural spring water. The higher calcium levels in spring water resulted in higher photosynthetic rates in plants held for 3 to 7 d in the lower salinities (0 to 5 ppt). Increased levels of calcium in salinities of 5 ppt or higher increased the photosynthetic rate only during the first 7 d of exposure, since acclimation occurred equally in individuals held for 2 to 8 wk in sewater diluted with distilled or spring water. This study suggests that the diverse algal floras, characteristic of estuaries on the west coast of Florida are in part the result of natural spring water mixing with seawater, sustaining the algae over short periods of low salinities.