cssi/SciSciGPT-SciSciNet huggingface dataset:
Adaptive particle-based approximations of the Gibbs posterior for inverse problems

In this work, we adopt a general framework based on the Gibbs posterior to update belief distributions for inverse problems governed by partial differential equations (PDEs). The Gibbs posterior formulation is a generalization of standard Bayesian inference that only relies on a loss function connecting the unknown parameters to the data. It is particularly useful when the true data generating mechanism (or noise distribution) is unknown or difficult to specify. The Gibbs posterior coincides with Bayesian updating when a true likelihood function is known and the loss function corresponds to the negative log-likelihood, yet provides subjective inference in more general settings. We employ a sequential Monte Carlo (SMC) approach to approximate the Gibbs posterior using particles. To manage the computational cost of propagating increasing numbers of particles through the loss function, we employ a recently developed local reduced basis method to build an efficient surrogate loss function that is used in the Gibbs update formula in place of the true loss. We derive error bounds for our approximation and propose an adaptive approach to construct the surrogate model in an efficient manner. We demonstrate the efficiency of our approach through several numerical examples.
Spreading Speeds for Reaction–Diffusion Equations with a Shifting Habitat

We study the spreading speeds of a species described by a reaction–diffusion equation with a shifting habitat on which the species’ growth rate increases in the positive spatial direction. Persistence and the rightward spreading speed have been previously investigated in the case that the species grows near positive infinity and declines near negative infinity. In the present paper we determine the leftward spreading speed for this case and both the rightward and leftward spreading speeds for the case that the species grows everywhere in space. We show that the spreading speeds depend on c, the speed at which the habitat shifts, and numbers $$c^*(\infty )$$ and $$c^*(-\infty )$$ given by the diffusion coefficient and species growth rates at $$\infty $$ and $$-\infty $$ respectively. We demonstrate that if the species declines near negative infinity, the leftward spreading speed is $$\min \{-c, c^*(\infty )\}$$ , and if species grows everywhere, under appropriate conditions, the rightward spreading speed is either $$c^*(\infty )$$ or $$c^*(-\infty )$$ , and the leftward spreading speed is one of $$c^*(\infty )$$ , $$c^*(-\infty )$$ and $$-c$$ . Our results show that it is possible for a solution to form a two-layer wave, with the propagation speeds analytically determined.
The Multi-mission Time Correlation System

All space missions must maintain a precise knowledge of time, as measured onboard the spacecraft. This is done by correlating measurements of time from the spacecraft's onboard clock with standard Earth time scales, as defined on the ground. Time correlation is essential for the correct timing of command executions, identification of received telemetry, use of ephemerides, instrument data processing, and many other related activities. In the past, space missions have typically developed their own custom software and procedures for performing time correlation. The Multi-Mission Time Correlation (MMTC) system is a software application and associated procedure that provides a reusable, customizable, and consistent means of performing time correlation for a variety of space missions. It leverages years of time correlation experience obtained from multiple past and current missions. The MMTC is a standalone and highly customizable application that is designed to perform time correlation for a variety of disparate missions. It is intended to reduce the cost of space mission ground systems by providing a mission agnostic solution. The MMTC is included in NASA's AMMOS catalog of reusable mission software components.
Scatter in Sunyaev-Zel'dovich effect scaling relations explained by inter-cluster variance in mass accretion histories

X-ray and microwave cluster scaling relations are immensely valuable for cosmological analysis. However, their power is limited by astrophysical systematics that bias mass estimates and introduce additional scatter. Turbulence injected into the intracluster medium via mass assembly contributes substantially to cluster non-thermal pressure support, a significant source of such uncertainties. We use an analytical model to compute the assembly-driven non-thermal pressure profiles of haloes based on Monte Carlo-generated accretion histories. We introduce a fitting function for the average non-thermal pressure fraction profile, which exhibits minimal dependence on redshift at fixed peak height. Using the model, we predict deviations from self-similarity and the intrinsic scatter in the Sunyaev--Zel'dovich effect observable-mass scaling relation ($Y_\mathrm{SZ}-M$) due solely to inter-cluster variation in mass accretion histories. We study the dependence of $Y_\mathrm{SZ}-M$ on aperture radius, cosmology, redshift, and mass limit. The model predicts $5-9\%$ scatter in $Y_\mathrm{SZ}-M$ at $z=0$, increasing as the aperture used to compute $Y_\mathrm{SZ}$ increases from $R_\mathrm{500c}$ to $5R_\mathrm{500c}$. The predicted scatter lies slightly below that of studies based on non-radiative hydro-simulations, illustrating that assembly history variance is likely responsible for a substantial fraction of scatter in $Y_\mathrm{SZ}-M$. This should be regarded as a lower bound, which will likely increase with the use of an updated gas density model that incorporates a more realistic response to halo assembly. As redshift increases, $Y_\mathrm{SZ}-M$ deviates more from self-similarity and scatter increases. We show that the $Y_\mathrm{SZ}-M$ residuals correlate strongly with the recent halo mass accretion rate, potentially providing an opportunity to infer the latter.
Evaluation of feasibility and image quality of a new radial quantitative T2 weighted imaging sequence for liver MRI.

Abstract Objectives To evaluate the clinical feasibility of a new T2 weighted sequence to calculate T2 relaxation times (T2RT) of liver lesions using two-dimensional radial turbo spin echo (2DRTSE) and to evaluate this sequence by performing image quality and relaxation time comparison of multiple liver lesions. Materials and methods This prospective analysis of 2DRTSE sequences (using 22 echoes) was performed in 19 patients with 36 liver lesions. Two radiologists independently obtained T2RTs for liver lesions and scored image quality and image artifacts. Lesions were classified as cyst, hemangioma, solid, or necrotic. T2RT values were compared. Inter-reader agreement was evaluated. Results The 2DRTSE images were considered good quality with few artifacts by both radiologists. Nineteen patients were included in the study, with a total of 36 liver lesions. Two of the liver lesions were classified as cysts, 7 as hemangiomas, 4 as necrotic lesions, and 23 as solid lesions. The concordance correlation coefficient was 0.996 for the calculated T2RT of each liver lesion between the two readers, indicating good agreement. There was statically significant difference of the calculated T2RT for each lesion type. Conclusion The 2DRTSE sequence can be performed and provides good T2W image quality and a quantitative T2RT map of the entire abdomen. The liver lesions can be distinguished based on the calculated T2RT using this technique. 2DRTSE could potentially supplant the current T2-weighted imaging sequence with the benefit of quantitative T2RTs.
Confocal Microscope-Based Laser Ablation and Regeneration Assay in Zebrafish Interneuromast Cells

Hair cells are mechanosensory cells that mediate the sense of hearing. These cells do not regenerate after damage in humans, but they are naturally replenished in non-mammalian vertebrates such as zebrafish. The zebrafish lateral line system is a useful model for characterizing sensory hair cell regeneration. The lateral line is comprised of hair cell-containing organs called neuromasts, which are linked together by a string of interneuromast cells (INMCs). INMCs act as progenitor cells that give rise to new neuromasts during development. INMCs can repair gaps in the lateral line system created by cell death. A method is described here for selective INMC ablation using a conventional laser-scanning confocal microscope and transgenic fish that express green fluorescent protein in INMCs. Time-lapse microscopy is then used to monitor INMC regeneration and determine the rate of gap closure. This represents an accessible protocol for cell ablation that does not require specialized equipment, such as a high-powered pulsed ultraviolet laser. The ablation protocol may serve broader interests, as it could be useful for the ablation of additional cell types, employing a tool set that is already available to many users. This technique will further enable the characterization of INMC regeneration under different conditions and from different genetic backgrounds, which will advance the understanding of sensory progenitor cell regeneration.
Spontaneous Chest Wall Herniation in Centrally Obese Patients: A Single-Center Experience of a Rare Problem:

BackgroundSpontaneous rib fractures, especially in association with chest wall herniation, represent an uncommon pathology. As such, there are little data analyzing approaches to treatment or regar...
On the Effects of Minimally Invasive Collision Avoidance on an Emergent Behavior

Swarms of autonomous agents are useful in many applications due to their ability to accomplish tasks in a decentralized manner, making them more robust to failures. Due to the difficulty in running experiments with large numbers of hardware agents, researchers typically resort to simulations with simplifying assumptions. While some assumptions are tolerable, we feel that two assumptions have been overlooked: one, that agents take up physical space, and two, that a collision avoidance algorithm is available to add safety to an existing algorithm. While there do exist minimally invasive collision avoidance algorithms designed to add safety while minimizing interference in the intended behavior, we show they can still cause unexpected interference. We use an illustrative example with a double-milling behavior and show, through simulations, that the collision avoidance can still cause unexpected interference and careful parameter tuning is needed.
Use of BIM for Study of Life Cycle Cost Analysis of Residential Complex

The initial costs of a building are quite small in comparison to the life cycle costs, as it is estimated that they represent less than 30% of the total life cycle cost of a building. Accordingly, if we consider integration of the life cycle cost of a building into the estimation of investment values, then we would have a better and clearer idea of how much our total operation costs are during and after construction process. Did an overview of Life Cycle Assessment and Modelling tools and BIM integrated LCC evaluations. Used BIM objectives by Krieder for to generate Life Cycle Cost Analysis of the Residential Building. Findings of this study demonstrate the opportunities to manage and estimate a reliable and accurate information on a building’s life cycle in real time by considering each element and its components into the calculation, which may change the metrics for a real estate economic evaluation in order to achieve sustainable and efficient property investment. The adoption of the building information modelling to generate relative LCCA databases directly benefits the real investment cost calculation for investors.
Large scale experiments and model validation of Pressure Peaking Phenomena-ignited hydrogen releases

Abstract The Pressure Peaking Phenomena (PPP) is the effect of introducing a light gas into a vented volume of denser gas. This will result in a nonequilibrium pressure as the light gas pushes the dense gas out at the vent. Large scale experiments have been performed to produce relevant evidence. The results were used to validate an analytical model. Pressure and temperature were measured inside a constant volume, while the mass flow and vent area were varied. The analytical model was based on the conservation of mass and energy. The results showed that increasing the mass flow rate, the peak pressure increases and with increasing the ventilation area, the peak pressure decreases. Peak pressure was measured above 45 kPa. Longer combustion time resulted in higher temperatures, increasing an underpressure effect. The experimental results showed agreement with the analytical model results. The model predicts the pressures within reasonable limits of+/-2 kPa. The pressure peaking phenomena could be very relevant for hydrogen applications in enclosures with limited ventilation. This could include car garages, ship hull compartments as well as compressor shielding. This work shows that the effect can be modeled and results can be used in design to reduce the consequences.
Muscle Atrophy Classification: The Need for a Pathway-Driven Approach

It is well known that muscles can waste away (atrophy) due to a lack of physical activity. Muscle wasting commonly presents with reduced muscle strength and an impaired ability to perform daily tasks. Several studies have attempted to categorize muscle atrophy into three main subgroups: physiologic, pathologic, and neurogenic atrophy. Physiologic atrophy is caused by the general underuse of skeletal muscle (e.g., bedridden). Pathologic atrophy is characterized as the loss of stimulus to a specific region (e.g., aging). Neurogenic atrophy results from damage to the nerve innervating a muscle (e.g., SMA, GBS). Mechanisms have been elucidated for many of these pathways (e.g., ubiquitin-proteasome system, NF-κB, etc.). However, many causes of muscle atrophy (e.g., burns, arthritis, etc.) operate through unelucidated signaling cascades. Therefore, this review highlights the underlying mechanisms of each subtype of muscle atrophy while emphasizing the need for additional research in properly classifying and identifying muscle atrophy.
Cannabis and Alcohol Co-Use and Condomless Anal Sex Among Men Who have Sex with Men Living with HIV: An Event-Level Analysis.

Men who have sex with men (MSM) account for more than two thirds of new HIV diagnoses annually. Sexual behavior that increases risk for onward transmission of HIV is associated with both alcohol and cannabis use. However, little is known about the influence of cannabis and alcohol co-use on engagement in condomless anal sex (CAS). The current study explored daily associations between substance use and CAS among HIV-positive MSM using a 42-day timeline followback interview (N = 101). Generalized estimating equation (GEE) logistic regression models were used to examine the association between cannabis and alcohol co-use and CAS at the sexual event while controlling for study site, condition, adherence to antiretroviral therapy, sex-related alcohol expectancies, and partner type. Participants provided data for 1052 sexual activity days, 60.7% of which involved CAS. Of 638 CAS days, 9.1% involved no substances, 72.0% involved either cannabis or alcohol use, and 18.9% involved cannabis and alcohol co-use. Results indicated that the odds of engaging in CAS were higher for sexual events in which cannabis and alcohol co-use occurred (aOR 2.98; 95% CI 1.27, 6.97) compared to events in which no substance use occurred (p = 0.012), but this relationship was no longer significant when cannabis and alcohol co-use was compared to single substance use (aOR 1.57; 95% CI 0.85, 2.90; p = 0.15). Future research should identify specific substance use (e.g., quantity) and partner characteristics (e.g., level of intoxication) that may uniquely influence the relationship between cannabis and alcohol co-use and condomless sex.
Object understanding: Investigating the path from percept to meaning.

Abstract Researchers tend to follow two paths when investigating categorization: 1) artificial classification learning tasks and 2) studies of natural conceptual organization involving reasoning from prior category knowledge. Largely separate, another body of research addresses the process of object recognition, i.e., how people identify what they are looking at strictly in terms of visual as opposed to semantic properties. The present work brings together elements from each of these approaches in order to address object understanding: the ubiquitous natural process of accessing meaning based on a realistic image of an everyday object. According to a widely held features-first framework, a stimulus is initially encoded as a set of features that is compared to stored category representations to find the best match. This approach has been successful for explaining artificial classification learning, but it bypasses how items are encoded and fails to include a role for top-down processing in constructing item representations. We used a speeded verification task to evaluate the features-first account using realistic stimuli. Participants saw photographic images of everyday objects and judged as quickly as possible whether a provided verbal description matched the picture. Category descriptions (basic-level labels) were verified significantly faster than descriptions of physical or functional properties. This suggests that people access the category of the stimulus prior to accessing its parsed features. We outline a construal account whereby the category is accessed first to construct a featural item interpretation rather than features being the basis for determining the category.
Training Nephrology Fellows in Home Dialysis in the United States.

Whether various home dialysis options are a better treatment for kidney failure than the almost half-century practice of center-based, thrice-weekly, staff-assisted high-efficiency hemodialysis remains an open question—no randomized trials exist. However, for an individual patient, home dialysis
Abstract 4413: Mnk activity in diffuse large b-cell lymphoma: targeting translation

Augmentation of protein translation has been observed in a number of human malignancies. We have previously demonstrated that cap-dependent protein translation is dysregulated in diffuse large B-cell lymphoma (DLBCL). This cancer-associated phenomenon may result in the deregulation of many proto-oncogenes and tumor suppressors leading to multiple cellular abnormalities. A major rate-limiting step in cap-dependent translation is the binding of eIF4E to the 7-methyl guanosine cap in the 5′ untranslated region of mRNA thus, bridging the eIF4F pre-initiation complex with the ribosome and initiating translation. eIF4E has been widely implicated as a proto-oncogene contributing to cancer development in numerous published reports. In addition to the mTOR signaling network, there is a potential for eIF4E to be modulated by the mitogen-activated protein kinases via map kinase interacting kinases (MNK). MNK proteins (MNK1 or MNK2) exert their effect on eIF4E through phosphorylation of eIF4E at serine 209. This phosphorylation is believed to promote B-cell lymphomagenesis. However, the physiologically relevant regulatory mechanisms and potential for targeting eIF4E phosphorylation in human B-cell lymphoma is largely unexplored. This study aims to elucidate the mechanistic and therapeutic effects of MNK regulation of eIF4E phosphorylation in DLBCL. Counter-intuitively, we have found differential expression of MNK2 over MNK1 in activated B-cell (ABC) lymphoma versus germinal center B-cell (GCB) lymphoma subtypes even though both are known to converge to phosphorylate eIF4E. Interestingly, ERK does not play a significant role in activating MNK1/2 or affect the downstream phosphorylation of eIF4E in DLBCL, however, p38 plays an important role in eFI4E phosphorylation via MNK1. We show that phosphorylation of eIF4E by MNK is critical for malignant cell survival in both ABC and GCB DLBCL. The inhibition of p38 resulted in a significant and selective killing of DLBCL via inactivation of MNK1 and down-regulation of MCL1. Therefore, p38 inhibition may be a useful targeted approach in DLBCL through its suppression of MNK mediated eIF4E phosphorylation. Citation Format: Ari Landon, Parameswary A. Muniandy, Ronald B. Gartenhaus. Mnk activity in diffuse large b-cell lymphoma: targeting translation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4413. doi:10.1158/1538-7445.AM2014-4413
Numerically Abnormal Chromosome Constitutions in Humans

As described in Chapter 2, the chromosome number may change in two different ways. Either the number of sets of chromosomes increases, resulting in polyploidy (a decrease, leading to haploidy, does not occur in humans), or the number of individual normal chromosomes changes, giving rise to aneuploidy.
Chapter 10 Accounting for Growth in the Information Age

Abstract The “killer application” of the new framework for productivity measurement presented in this paper is the impact of information technology (IT) on economic growth. A consensus has emerged that the remarkable behavior of IT prices provides the key to the surge in U.S. economic growth after 1995. The relentless decline in the prices of information technology equipment and software has steadily enhanced the role of IT investment. Productivity growth in IT-producing industries has risen in importance and a productivity revival is underway in the rest of the economy. The surge of IT investment in the United States after 1995 has counterparts in all other industrialized countries. It is essential to use comparable data and methodology in order to provide rigorous international comparisons. A crucial role is played by measurements of IT prices. The U.S. national accounts have incorporated measures of IT prices that hold performance constant since 1985. Schreyer [Schreyer, Paul (2000), “The contribution of information and communication technology to output growth: A study of the G7 Countries”. Organization for Economic Co-operation and Development, Paris, May 23] has extended these measures to other industrialized countries by constructing “internationally harmonized prices”. The acceleration in the IT price decline in 1995 triggered a burst of IT investment in all of the G7 nations – Canada, France, Germany, Italy, Japan, the UK, as well as the U.S. These countries also experienced a rise in productivity growth in the IT-producing industries. However, differences in the relative importance of these industries have generated wide disparities in the impact of IT on economic growth. The role of the IT-producing industries is greatest in the U.S., which leads the G7 in output per capita.
Reaction Order of Saccharomyces cerevisiae Alpha-Factor-Mediated Cell Cycle Arrest and Mating Inhibition

Alpha-factor-mediated cell cycle arrest and mating inhibition of a mating-type cells of Saccharomyces cerevisiae have been examined in liquid cultures. Cell cycle arrest may be monitored unambiguously by the appearance of morphologically abnormal cells after administration of alpha factor, whereas mating inhibition is determined by comparing the mating efficiency in the absence or presence of added alpha factor. For both cell cycle arrest and mating inhibition, a dose-dependent response may be observed at limiting concentrations of the pheromone. If cell cycle arrest and mating inhibition require a small number of alpha-factor molecules, one might expect that responsive/nonresponsive cells = K(alpha factor)(N) where N is the order of dependence of cell cycle arrest (or mating inhibition) on alpha-factor concentration. The value of N has been determined to be 0.98 +/- 0.18 (standard error of the mean) for cell cycle arrest and 1.08 +/- 0.32 for mating inhibition. These results support the notion that saturation of a single site by alpha factor is sufficient to cause cell cycle arrest or mating inhibition of a mating-type cells.
Nucleic Acid and Protein Metabolism of the Axon

Several factors have contributed to the generally held notion that the axon depends wholly upon its cell body for all of its soluble and structural proteins. Historically, the nineteenth century experiments of Waller and Turck, demonstrating the importance of continuity between axon and cell body for preserving structural integrity of the axon, were perhaps most compelling in structuring subsequent thinking about the axon’s dependency. A second factor was the concept of axoplasmic flow, a proposed mechanism whereby the perikaryon supplies the axon with its metabolic needs. This was a logical hypothesis that followed directly from the studies involving axonal degeneration. Indeed, Barker states in his textbook published in 1899,(3): “To explain the influence of the cell body upon the fibre, Goldscheider has advanced a very ingenious hypothesis. He suggests that it is most probable that there is an actual transport of a material, perhaps a fermentlike substance, from the cell along the whole course of the axone to its extremity, and first through the influence of this chemical body the axone is enabled to make use for its nutrition of the material placed at its disposal in its anatomical course.” The phenomenon of axoplasmic flow is now well established, owing to the classic experiments of Weiss and co-workers that stimulated the large number of studies that followed subsequently (see Chapter 18, Vol. II of this Handbook).However, in view of the paucity of information at that time and the lapse of more than 40 years before the phenomenon was finally demonstrated, Goldscheider may be credited with having had profound intuitive insight.
Mechanism of digeranylgeranylation of Rab proteins. Formation of a complex between monogeranylgeranyl-Rab and Rab escort protein.

Rab proteins are Ras-related small GTPases that are digeranylgeranylated at carboxyl-terminal cysteines, a modification essential for their action as molecular switches regulating intracellular vesicular transport. Geranylgeranylation of Rabs is a complex reaction that requires a catalytic Rab geranylgeranyl transferase (GGTase) and a Rab escort protein (REP). REP binds unprenylated Rab and presents it to Rab GGTase. After GG transfer, REP remains associated with diGG-Rab, which leads to insertion of the Rab into a specific membrane. We used recombinant Rab1a single cysteine mutants that accept only one GG group to study the mechanism of the digeranylgeranylation reaction. Using the prenylation assay, gel filtration chromatography, and density ultracentrifugation, we show that REP, but not Rab GGTase, forms a stable complex with unprenylated, monoGG- and diGG-Rab1a. The REP.monoGG-Rab1a complex is stable in the presence of detergents or phospholipids, whereas the REP.diGG-Rab1a complex partially dissociates under these conditions. The stoichiometry of the REP.Rab complex appears to be 1:1 before prenylation. Prenylation induces a change in complex stoichiometry, with the formation of a 2:2 or 2:1 REP.Rab complex. A possible mechanism by which Rab proteins are digeranylgeranylated is suggested by the current studies. We propose that each geranylgeranyl addition is an independent reaction that leads to the production of monoGG-Rab and diGG-Rab, respectively. The stability of the REP.monoGG-Rab complex prevents monoGG-Rab from dissociating from REP prior to the second geranylgeranylation reaction, ensuring efficient digeranylgeranylation of Rab substrates.
Ever Ever After

Summary In this article the Drs. Perls look at twelve couples who have each been married at least 30 years. Common values among the couples are explored including commitment, mutual respect, philosophical viewpoints, and monogamy. Developmental experiences and socio-cultural changes are presented as a framework for understanding how this particular sample of couples continued in their longterm relationships with satisfaction.
The range of validity of the two-body approximation in models of terrestrial planet accumulation: II. Gravitational cross sections and runaway accretion

The validity of the two-body approximation in calculating encounters between planetesimals has been evaluated as a function of the ratio of unperturbed planetesimal velocity (with respect to a circular orbit) to mutual escape velocity when their surfaces are in contact (V/V-sub-e). Impact rates as a function of this ratio are calculated to within about 20 percent by numerical integration of the equations of motion. It is found that when the ratio is greater than 0.4 the two-body approximation is a good one. Consequences of reducing the ratio to less than 0.02 are examined. Factors leading to an optimal size for growth of planetesimals from a swarm of given eccentricity and placing a limit on the extent of runaway accretion are derived.
Night-time ionization in the lower ionosphere—II. Distribution of electrons and positive and negative ions

Abstract In Part I of this paper we have discussed the nature of the night-time variation of certain ionospheric parameters, such as height, electron density, and absorption at frequencies in the range 16 kc/s-18.3 Mc/s, and have deduced the time and height variations of the (effective) coefficient of recombination in the ionosphere at night for heights in the range 80–110 km. In this paper, we deduce from the observational results presented in Part I, the distributions of various positive and negative ions and of electrons in the lower ionosphere at night. The positive ions are the atomic ions X+, which are only predominant at night, and the molecular ions YZ+ that control the daytime ionization. It is found that the concentration of X+ increases from a negligible value at about 87 km to about 7 × 103/cm3 at 110 km. Since such ions recombine with a very small coefficient, their concentrations do not appreciably alter during the entire night. While the concentration of negative ions decreases with the progress of the night, the ratio of the concentration of negative ions and electrons remains constant. There is, however, a rapid fall of this ratio from 80 to 110 km by a factor of about 7 × 10−4.
Reversal of jejunal water secretion by glucose in rats exposed to coliform enterotoxins

Abstract Glucose absorption and glucose-facilitated water transport were assessed in rats exposed to semipurified preparations of the heat-labile (LT) and heat-stable (ST) enterotoxins of Escherichia coli, Klebsiella pneumoniae , and Enterobacter cloacae by in vivo jejunal perfusion of these toxins alone and with varying amounts of glucose. Progressive increases in the glucose concentration of from 12 to 56 mm resulted in incremental rises in water absorption from perfusates containing each of these toxins, with similar Δ water values to those for the electrolyte perfusion solution without toxins. Water secretion was reversed to absorption by the addition of 12 mm glucose when secretion was mild, but 24 mm was required to achieve this in the presence of severe secretion; absolute values for water transport did not return to normal in any instance. Glucose absorption from solutions containing 24 and 56 mm glucose was severely reduced by all of the ST toxins and marginally reduced by some of the LT toxins; the effect of LT was not attributable to the toxin itself, however, but to another unidentified factor present in LT, but not ST, preparations from both toxigenic and nontoxigenic strains. These observations indicate that glucose-facilitated water transport remains intact in intestinal tissue exposed to various coliform enterotoxins and that this occurs despte the presence of impaired glucose absorption in some instances. They provide a rational basis for treatment with oral glucose-electrolyte solutions of persons whose diarrhea is caused by toxigenic coliform bacteria.
EPISTEMOLOGICAL PERSPECTIVES IN THE SCIENTIFIC STUDY AND EVALUATION OF EXECUTIVE FUNCTION

In this article, epistemological perspectives that have shaped and affected the scientific quest for understanding what neuropsychologists term “executive functions” are reviewed. Executive functions refer to the control functions of cognition and behavior. The underlying thesis of the paper is that one’s epistemological orientation determines how one sees the interaction between brain functions and our status in the world. Each different orientation thus carries with it implications with regard to how executive functions operate, as well as how, therefore, one should try to assess them. Until recently, these functions were approached through two primary epistemological points of view. One is analytic, which has its roots in the positivistic movement. The other approach is synthetic, otherwise known as “romantic science”, and forms the basis of the work of the prominent Russian neuropsychologist A.R. Luria. A third epistemological perspective, articulated under the umbrella of ‘embodied cognition’ approaches, has been advanced in the last 20 years, and is associated most closely with the work of Francisco Varela. A review of, and reflection on how these perspectives have affected research and clinical practice in neuropsychology is provided.
A Mixed Oxide-Hydride Perovskite

Hydrides are unusual materials in which hydrogen is negatively charged. Compounds that contain both hydride and oxide ions are particularly rare. In his Perspective, [Poeppelmeier][1] highlights [ Hayward et al .][2]'s synthesis of a perovskite containing both hydride and oxide ions. The material may have unusual magnetic and electronic properties. [1]: http://www.sciencemag.org/cgi/content/full/295/5561/1849 [2]: http://www.sciencemag.org/cgi/content/short/295/5561/1882
MediaScripting: teaching introductory CS by through interactive graphics scripting (abstract only)

upswing, Computer science teachers continue to strive for new examples and problems to interest millenials. The Media Computation approach (Guzdial 2003) has proven successful in attracting students in contexts from community colleges to R1 universities - students are clearly excited by writing programs that make images. In this project, take Media Computing in new directions: we have students build images by interactively scripting an application, which means that they can more easily experiment and mix work that they create "by hand" and work that they create "by programming"; we work collaboratively with studio art faculty, so students build works that must meet underlying design criteria; we teach using the workshop approach, so most classes involve students working in small teams on a set of problems; and we use a multi-paradigm approach - students make images using functional, declarative, imperative, and object-oriented techniques.This approach has proven quite successful - our enrollments are up (at least 33% in CS1, 50% in CS2). We are attracting more women (now 1/3 of our students). And comparative data suggest that our students gain significantly more confidence in their abilities than do student in other introductory science courses.
Analysis of the current-voltage characteristics of Silicon on Ferroelectric Insulator Field Effect Transistor (SOF-FET)

This paper presents the current-voltage (I–V) characteristic of our proposed Silicon-on-Ferroelectric Insulator Field Effect Transistor (SOF-FET). The proposed SOF-FET is based on the concept of silicon-on-insulator (SOI) device technology and it utilizes a negative capacitance that can be achieved by inserting a layer of ferroelectric insulator inside the bulk silicon substrate of the device. The negative capacitance (NC) effect can provide an internal signal boosting that leads to steeper subthreshold slope, which is the prime requirement for ultra-low-power circuit operation. Here we have analyzed the impacts of channel doping profile on the behavior of the proposed SOF-FET. The major focus of this paper is the investigation of the current-voltage (I–V) characteristics of the proposed SOF-FET. Here the (I–V) characteristics of both the subthreshold and the saturation regions of the proposed device have been derived.
Lateral release and medial plication for recurrent patella dislocation.

This study aims to report the long-term results of lateral release and medial plication in patients with recurrent patellar dislocation. In this study, 31 patients who underwent surgery for recurrent patellar dislocation were retrospectively reviewed between 1994 and 2004. Among the 31 patients were 12 male and 19 female patients. The average age was 23.9 ± 4.8 years, and the mean follow-up period was 11.6 ± 2.4 years. Three patients had postoperative dislocations. The mean Kujala score significantly improved from 57.5 ± 13.2 points preoperatively to 89.2 ± 8.7 points at the final follow-up (P < 0.0001). The median Tegner activity score significantly improved from 3 (range, 1–5) at preoperative examination to 7 (range, 3–9) at the final follow-up (P < 0.0001). Ten patients were rated as excellent, 18 as good, 2 as fair, and 1 as poor. The congruence angle improved from 16.5° ± 3.0° to −2.8° ± 2.7°, and the lateral patellofemoral angle improved from −4.2° ± 1.9° to 8.2° ± 2.5°. There was no case of osteoarthritis at the final follow-up. Percutaneous lateral release and medial plication showed satisfactory results with limited morbidity in the long-term follow-up. This traditional method remains a simple and effective surgical procedure for recurrent patellar dislocation. Therapeutic, Level IV.
Materials structure-property prediction using a self-architecting neural network

An important trend in materials research is to predict properties for a new material before committing experimental resources. Often the prediction is motivated by the search for a material with a unique combination of properties. The selection of a property or feature is crucial to the plausibility of the prediction. This paper proposes the use of a self-architecting neural network to model the relation between materials structure and properties for the purpose of predicting the properties of new materials, i.e. to predict properties for an unknown compound. In this paper, we summarize the prediction attained with the proposed neural network structure referred to as the Orthogonal Functional Basis Neural Network (OFBNN). The OFBNN, which combines a new basis selection process and a regularization technique, not only gives us a more computationally tractable method, but better generalization performance. Simulation studies presented here demonstrate the performance, behavior and advantages of the proposed network.
The spirit moves where there is a need in higher education

A Chinese American female professor discusses her teaching challenges and how her Christian faith influenced the educational methods she created to have students introspectively look within their humanness and spirituality as part of their assignments. Her approach to spiritual mentorship is also addressed.
The real final exam.

Editor’s Note: Every departing Medical Student, Graduate Student, Urology Research Resident, and Post-Doctoral Fellow trained in Dr. Donald S. Coffey’s laboratory or classroom for 4 decades has been given this “real final exam”—in either oral, written, or both forms. Some believe the wisdom in it passed on to the next generations of cancer researchers is as vast and generous and dedicated to the eradication of cancer as the heart of its author. Coffey passed the test, and then disseminated the answers for all students-now including those new, young 21 Century investigators at this meeting.
The PC in an Indian urban slum: enterprise and entrepreneurship in ICT4D 2.0

This paper examines the embedding of information and communication technology (ICT) tools in everyday practices among underserved populations in urban India. Using ethnographic investigations of PC-aided micro- and small enterprises (MSEs) in a low-income slum neighborhood in Mumbai, it pursued three broad research goals: first, to etch out organic ICT immersions in underserved technology environments; second, to articulate a new and evolving socio-technical system in an urban slum ecology; third, to seek a fit between goals of ICT for development and impacts of PC-aided enterprise on ICT access and adoption. Based on the ICT4D 2.0 approach interrogating the technology-for-development discourse, this paper substantiates the need for a “new view of the world's poor: one that views the poor not as passive consumers but agile agents and innovative producers of ICT products and services.”
Molecular Bases and Role of Viruses in the Human Microbiome

Viruses are dependent biological entities that interact with the genetic material of most cells on the planet, including the trillions within the human microbiome. Their tremendous diversity renders analysis of human viral communities (“viromes”) to be highly complex. Because many of the viruses in humans are bacteriophage, their dynamic interactions with their cellular hosts add greatly to the complexities observed in examining human microbial ecosystems. We are only beginning to be able to study human viral communities on a large scale, mostly as a result of recent and continued advancements in sequencing and bioinformatic technologies. Bacteriophage community diversity in humans not only is inexorably linked to the diversity of their cellular hosts but also is due to their rapid evolution, horizontal gene transfers, and intimate interactions with host nucleic acids. There are vast numbers of observed viral genotypes on many body surfaces studied, including the oral, gastrointestinal, and respiratory tracts, and even in the human bloodstream, which previously was considered a purely sterile environment. The presence of viruses in blood suggests that virome members can traverse mucosal barriers, as indeed these communities are substantially altered when mucosal defenses are weakened. Perhaps the most interesting aspect of human viral communities is the extent to which they can carry gene functions involved in the pathogenesis of their hosts, particularly antibiotic resistance. Persons in close contact with each other have been shown to share a fraction of oral virobiota, which could potentially have important implications for the spread of antibiotic resistance to healthy individuals. Because viruses can have a large impact on ecosystem dynamics through mechanisms such as the transfers of beneficial gene functions or the lysis of certain populations of cellular hosts, they may have both beneficial and detrimental roles that affect human health, including improvements in microbial resilience to disturbances, immune evasion, maintenance of physiologic processes, and altering the microbial community in ways that promote or prevent pathogen colonization.
Is higher lactate an indicator of tumor metastatic risk? A pilot MRS study using hyperpolarized (13)C-pyruvate.

Rationale and Objectives Cancer cells generate more lactate than normal cells under both aerobic and hypoxic conditions—exhibiting the so-called Warburg effect. However, the relationship between the Warburg effect and tumor metastatic potential remains controversial. We intend to investigate whether the higher lactate reflects higher tumor metastatic potential. Materials and Methods We used hyperpolarized 13 C-pyruvate magnetic resonance spectroscopy (MRS) to compare lactate 13 C-labeling in vivo in mouse xenografts of the highly metastatic (MDA-MB-231) and the relatively indolent (MCF-7) human breast cancer cell lines. We obtained the kinetic parameters of the lactate dehydrogenase (LDH)–catalyzed reaction by three methods of data analysis including the differential equation fit, q-ratio fit, and ratio fit methods. Results Consistent results from the three methods showed that the highly metastatic tumors exhibited a smaller apparent forward rate constant ( k + = 0.060 ± 0.004 s −1 ) than the relatively indolent tumors ( k + = 0.097 ± 0.013 s −1 ). The ratio fit generated the greatest statistical significance for the difference ( P = .02). No significant difference in the reverse rate constant was found between the two tumor lines. Conclusions The result indicates that the less metastatic breast tumors may produce more lactate than the highly metastatic ones from the injected 13 C-pyruvate and supports the notion that breast tumor metastatic risk is not necessarily associated with the high levels of glycolysis and lactate production. More studies are needed to confirm whether and how much the measured apparent rate constants are affected by the membrane transporter activity and whether they are primarily determined by the LDH activity.
Optimization of Electrical Output in Response to Mechanical Input in Piezoceramic Laminated Shells

The piezoelectric ceramic, Lead Zirconate Titanate (PZT), is capable of producing large voltages in response to an applied mechanical stress when employed in a laminate manufactured using the THUNDER process. This study addresses the issue of optimizing mechanical parameters in a PZT unimorph to maximize charge generated due to mechanical strain. The PZT unimorph structure is initially curved and generates a surface charge when vertically loaded. In the analysis, the principles of shallow shell and linear piezoelectric laminate theories are employed to obtain an expression for charge in terms of geometry, material properties and loading. Analytical relationships are then derived that can be used to optimize the charge produced from these generators. Numerical parametric studies are then conducted to maximize the charge generation by manipulating dimensions of the components. Experimental results show a “convergence” to a theoretically predicted ‘applied force vs. deformation’ relationship when the PZT unimorph is subjected to a pressure load. Finally, a charge collecting circuitry for harvesting the charge produced is designed and presented.Copyright © 2003 by ASME
Vulcanization Characteristics of Mercaptobenzothiazole Derivatives

Abstract WITHIN the past few years much progress has been made in the development of rubber vulcanization accelerators of the semi-ultra type which exhibit no prevulcanization or scorch during the ...
A survey of streamer and diffuse glow dynamics observed in sprites using telescopic imagery

[1] While the fine structure in sprites can assume a wide variety of shapes, sizes, and timescales, certain patterns such as upward branching, downward branching, beading, columns, bidirectional streamers, and propagating large-scale diffuse glow regions are repeatedly observed. Example cases of these streamer and diffuse glow dynamics observed in sprites are presented using video data obtained by a telescopic imaging system in July–August 1998 and are compared to predictions of current sprite and streamer theories. The previously unreported propagating diffuse glows move slowly (∼104 m/s) and are broader than that predicted for a streamer formation at the same altitude. Sudden brightening of slowly developing negative streamers may be indicative of a return stroke process in which the streamers connect with charge in a lowered ionosphere. Meteoric dust particles in the upper atmosphere may be responsible for the fine beading that exists in many negative streamers and may cause plasma enhancements that initiate double-headed streamers. Beads at the base of columns can glow for over 100 ms while slowly drifting upward (∼104 m/s). Columns may initiate from downward branching positive streamers. Faint positive streamers are observed at the base of and/or preceding large bright sprite events. Some sprites may initiate as double-headed streamers formed in localized regions of enhanced electron density. A transition between the streamer formation region and the diffuse glow region is observed at ∼80-km altitude. No fine structure is observed in telescopic images of the diffuse glow region also referred to as the “sprite halo” [Barrington-Leigh and Inan, 2001].