cssi/SciSciGPT-SciSciNet huggingface dataset:
Differences of opinion and selection bias in the credit rating industry

Abstract Many regulations use private sector credit ratings to determine investment prohibitions and capital requirements for institutional portfolio investments. These regulations implicitly assume that different agencies have equivalent rating scales, despite the fact that some agencies assign systematically higher ratings than others. We assess the appropriateness of these regulatory practices by testing whether observed rating differences reflect different rating scales or simply result from sample selection bias. Our analysis reveals only limited evidence of selection bias. We also ask what types of firms of firms are most likely to seek ratings from the agencies with higher rating scales. Our analysis uncovers no evidence that firms seek ratings from these agencies to clear specific regulatory hurdles or to reduce ex ante uncertainty about default risk.
Deuterium-tritium results of TFTR's alpha collector

An escaping alpha collector probe has been developed for the deuterium-tritium (DT) phase of the Tokamak Fusion Test Reactor (TFTR) to complement the results of the lost alpha scintillator detectors, which have been operating on TFTR since 1988. Measurements of the energy distribution of escaping alphas have been made by measuring the range of alphas implanted into nickel foils located within the alpha collector. Exposed samples have been analysed for four DT plasma discharges at plasma currents of 1.0 and 1.8 MA. The results at 1.0 MA are in good agreement with predictions for first orbit alpha loss at 3.5 MeV. The 1.8 MA results, however, indicate a large anomalous loss of partially thermalized alphas at an energy ~30% below the birth energy and at a total fluence nearly an order of magnitude above the expected first orbit loss. This anomalous loss is not observed with the lost alpha scintillator detectors in DT plasmas but does resemble the anomalous `delayed' loss seen in DD plasmas. Several potential explanations for this loss process are examined. None of the candidate explanations proposed thus far are fully consistent with the anomalous loss observations
Kinetics and Mechanisms for TCE Oxidation by Permanganate

The oxidation of trichloroethylene (TCE) by permanganate proceeds in three sequential reaction steps. In the initial step, a cyclic hypomanganate ester is formed via an activated organometallic complex. The activation parameters for this step were determined to be Ea = 41.46 kJ/mol, ΔH⧧ = 39 kJ/mol, and ΔS⧧ = −14 J/mol. The initial reaction is a rate-limiting step (second-order rate constant k1p = 0.65−0.68 M-1 s-1 at 21 °C) and independent of pH. In the second step, the decomposition of the cyclic ester with complete chlorine liberation proceeds quickly via various reaction pathways to form four carboxylic acids. Approximately 77% of the TCE was transformed to formic acid at pH 4, while 95−97% of the TCE was transformed to oxalic and glyoxylic acids at pH values of 6−8. Kinetic data suggest that the decomposition rate of the cyclic ester is at least 100 times higher than its formation rate. In the final step, all carboxylic acids are oxidized by permanganate to the final product, CO2. Second-order rate c...
A Method for the Experimental Study of Variable Energy Blast Waves

Abstract A low inductance exploding wire circuit is shown to be a good means for the investigation of variable energy cylindrical blast waves. The circuit was designed so that the energy stored in a large capacitor could be discharged with the energy transferred to the wire in a single pulse with no oscillation and no dwell time or restrike. Voltage and current can then be measured as a function of time so that energy release as a function of time can be determined. Fine wires of silver, cadmium, and zinc were exploded in air and in argon at pressures from 150 torr to 760 torr. Energy release as a function of time was determined from measurements and schlieren photographs showing the flow field generated, taken with an ultra-high speed framing camera capable of up to 2 × 106 frames/sec. Plexiglas plates at the wire ends were employed to confine the expansion for true cylindrical symmetry. Some comparison of the measurements was made with analyses. The measurements show that the classical blast wave theory...
Lessons learned: technology transfer from terrestrial spectroscopy to biomedicine

The spectral radiance measured by an imaging spectrometer for a material on the earth's surface has significant dependence on environmental factors such as the illumination environment and the atmospheric conditions. This dependence has limited the success of material identification algorithms that rely on hyperspectral image data without associated ground truth information. An important advantage of hyperspectral data is that the sensor spectral dimensionality typically exceeds the dimensionality of the signature variability for any material of interest. We have shown, for example, that the set of observed 0.4 - 2.5 micrometers spectral radiance vectors for a material on the earth's surface lies in a low-dimensional subspace of the hyperspectral measurement space. This analysis has led to robust algorithms for invariant subpixel image analysis that have been applied to a number of remote sensing applications. Similar computational methods can be applied to biomedical images by introducing variability models for the signatures of interest. We present results for material identification in remote sensing images as well as for the quantification of cell population in 3D brain tissue samples.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Scoring system to assess severity of congenital heart disease during the first year of life.

Using a group of 419 Japanese infants with congenital heart disease with increased pulmonary blood flow, a scoring system for assessment of severity was devised. The parameters chosen for objectivity and ease of evaluation were body weight, respiratory rate, maternal history of feeding difficulty, cry and wheeze or cough. Prognosis improved with higher scores. It is felt that this system can be used to aid in communication among physicians and ancillary personnel who care for infants with congenital heart disease.
Parenchymal splenic metastasis is an independent negative predictor of overall survival in advanced ovarian, fallopian tube and primary peritoneal cancer

Abstract Objective The purpose of this study was to evaluate the significance of parenchymal splenic metastasis (PSM) in ovarian (OC), fallopian tube (FTC), and primary peritoneal cancer (PPC). Methods All patients with stage IIIB–IV OC, FTC, and PPC undergoing primary cytoreduction from 2001 to 2010 at our institution were identified. In patients undergoing splenectomy, pathology was reviewed for the presence of PSM. Multivariate Cox regression and Kaplan–Meier survival analysis were used to evaluate factors associated with overall survival (OS). Results Of 576 patients identified, stage was: IIIB — 23 (4%), IIIC — 468 (81.2%), and IV — 85 (14.8%). Optimal cytoreduction was achieved in 430 patients (74.7%), including 85 of 97 patients (87.6%) undergoing splenectomy. PSM was identified in 20 patients (20.6%) undergoing splenectomy, including 3 of 5 patients (60%) with radiographically identified parenchymal liver metastases and 17 of 92 patients (18.5%) without such radiographic findings ( P =0.059). Age, preoperative albumin, residual disease, stage, bulky upper abdominal disease, IP chemotherapy, and PSM were associated with OS on univariate analysis. Splenectomy was not associated with survival. Age, preoperative albumin, residual disease, stage, and PSM (HR=0.46; 95% CI, 0.27–0.77) were associated with OS on multivariate analysis. In the subset of patients undergoing splenectomy, OS was lower for patients with PSM versus those without PSM (28.5 v 51.2months, P =0.004). Conclusions PSM is independently associated with decreased OS in patients with advanced OC, FTC, and PPC. PSM occurs in the setting of other evidence of hematogenously disseminated disease, but also occurs outside this setting. PSM should be considered a criterion for stage IV disease.
Mechanical and thermal performance of aerogel-filled sandwich panels for building insulation

Abstract Monolithic silica aerogels provide exceptional thermal insulation but have low mechanical properties. For instance, their flexural strength is typically 0.03–0.08 MPa. Here, we report on the development of a truss-core sandwich panel filled with compacted aerogel granules, designed to provide both mechanical support and thermal insulation. Mechanical and thermal properties of the sandwich panel prototype were measured and compared with theoretical models available in the literature. The models give a good description of the properties of aerogel-filled truss-core sandwich panels.
Interleukin-6 Synthesis in Human Chondrocytes Is Regulated via the Antagonistic Actions of Prostaglandin (PG)E2 and 15-deoxy-Δ12,14-PGJ2

Background Elevated levels of interleukin-6 (IL-6), prostaglandin (PG)E(2), PGD(2) and its dehydration end product 15-deoxy-Δ(12,14)-PGJ(2) (15d-PGJ(2)) have been detected in joint synovial fluids from patients with rheumatoid arthritis (RA). PGE(2) directly stimulates IL-6 production in human articular chondrocytes. However, the effects of PGD(2) and 15d-PGJ(2) in the absence or presence of PGE(2) on IL-6 synthesis in human chondrocytes have yet to be determined. It is believed that dysregulated overproduction of IL-6 is responsible for the systemic inflammatory manifestations and abnormal laboratory findings in RA patients. Methodology/principal findings Using the T/C-28a2 chondrocyte cell line as a model system, we report that exogenous PGE(2) and PGD(2)/15d-PGJ(2) exert antagonistic effects on IL-6 synthesis in human T/C-28a2 chondrocytes. Using a synthesis of sophisticated molecular biology techniques, we determined that PGE(2) stimulates Toll-like receptor 4 (TLR4) synthesis, which is in turn responsible for the activation of the ERK1/2, PI3K/Akt and PKA/CREB pathways that phosphorylate the NF-κB p65 subunit leading to NF-κB activation. Binding of the activated NF-κB p65 subunit to IL-6 promoter induces IL-6 synthesis in human T/C28a2 chondrocytes. PGD(2) or 15d-PGJ(2) concurrently downregulates TLR4 and upregulates caveolin-1, which in turn inhibit the PGE(2)-dependent ERK1/2, PI3-K and PKA activation, and ultimately with NF-κB-dependent IL-6 synthesis in chondrocytes. Conclusions/significance We have delineated the signaling cascade by which PGE(2) and PGD(2)/15d-PGJ(2) exert opposing effects on IL-6 synthesis in human chondrocytes. Elucidation of the molecular pathway of IL-6 synthesis and secretion by chondrocytes will provide insights for developing strategies to reduce inflammation and pain in RA patients.
HIGH-SPEED PARTICLE BEAM GENERATION: SIMPLE FOCUSING MECHANISMS

Abstract Modern chemical characterization instruments employ an aerosol inlet that transmits atmospheric aerosols to the low pressure source region of a time-of-flight mass spectrometer, where particles are ablated and ionized using high energy irradiation. The ions when analyzed in the mass spectrometer yield information about the elemental composition of airborne aerosols. Often, the rate at which particles are analyzed is limited by the transmission rate of the inlet used. Depending on their size, particles are lost during sampling usually due to inertial effects or diffusion. Often simple capillaries and conical nozzles are used as primary focusing elements in the formation of high-speed particle beams. Due to the basic nature of the focusing mechanism, such elements transmit particles efficiently over a narrow size range. This size range strongly depends on the nozzle geometry and operating conditions. In this work, numerical techniques are used to (a) simulate fluid and particle transport in axi-symmetric nozzles, (b) help understand and identify the mechanisms by which particle beams are formed in capillaries and conical nozzles, and (c) illustrate the contrasting nature of the beams thus formed. Particle focusing is also simulated in some typical inlets to validate the predictions and illustrate the merits and drawbacks of each design.
Alzheimer disease and Down syndrome: factors in pathogenesis

There is evidence to suggest that certain shared features exist in the pathogenesis of vascular disease and Alzheimer disease (AD) in the general population. In Down syndrome (DS) all adults over the age of 40 years develop sufficient neuropathology for a diagnosis of AD. However, vascular disease is not as common in DS as it is in the general population, particularly with respect to the development of atheromas. We discuss biological mechanisms and risk factors that may be common to both diseases including cholesterol metabolism, inflammation, plasminogen activator inhibitor and apolipoprotein E (Apo E). The study of individuals with DS may help to identify common pathogenic links as well as a disassociation between vascular disease and AD.
Effect of infection by the shot-hole fungus, Wilsonomyces carpophilus, on drop and quality of almond fruit

Almond fruits were inoculated with suspensions containing 103, 104 or 105 conidia per mL of Wilsonomyces carpophilus beginning when fruits emerged from the hypanthium and continuing at approximately weekly intervals until they reached full size and embryo development began. More small than mid-sized fruits fell and abscission ceased when fruits reached maximum size. Abscission of mid-sized fruits generally increased with increasing inoculum concentration, and lesions were most abundant on mid-sized fruits. The kernel quality of infected and healthy fruits were compared in 1994 and 1995. Mid- to full-sized fruits were inoculated one or three times with 10 conidia per mL of W. carpophilus. Kernels from inoculated and non-inoculated fruits did not differ in weight, length, or percentage of kernels covered with gum deposits or incompletely filled.
Volcanic hazards and public response

Although scientific understanding of volcanoes is advancing, eruptions continue to take a substantial toll of life and property. Some of these losses could be reduced by better advance preparation, more effective flow of information between scientists and public officials, and better understanding of volcanic behavior by all segments of the public. The greatest losses generally occur at volcanoes that erupt infrequently where people are not accustomed to dealing with them. Scientists sometimes tend to feel that the blame for poor decisions in emergency management lies chiefly with officials or journalists because of their failure to understand the threat. However, the underlying problem embraces a set of more complex issues comprising three pervasive factors. The first factor is the volcano: signals given by restless volcanoes are often ambiguous and difficult to interpret, especially at long-quiescent volcanoes. The second factor is people: people confront hazardous volcanoes in widely divergent ways, and many have difficulty in dealing with the uncertainties inherent in volcanic unrest. The third factor is the scientists: volcanologists correctly place their highest priority on monitoring and hazard assessment, but they sometimes fail to explain clearly their conclusions to responsible officials and the public, which may lead to inadequate public response. Of all groups in society, volcanologists have the clearest understanding of the hazards and vagaries of volcanic activity; they thereby assume an ethical obligation to convey effectively their knowledge to benefit all of society. If society resists, their obligation nevertheless remains. They must use the same ingenuity and creativity in dealing with information for the public that they use in solving scientific problems. When this falls short, even excellent scientific results may be nullified.
Energy storage and heat extraction – From thermally activated building systems (TABS) to thermally homeostatic buildings

Abstract The trend toward high envelope R- value for building energy efficiency made sense because at the starting point when the trend began in 1980s and 1990s buildings were poorly insulated. The advantage of high performance envelope was based on the consideration of envelope heat transfer and building heat balance (balance between heat transfer loss and fuel heat production). However, high performance envelope is not the silver bullet to building energy efficiency. A more comprehensive consideration of building energy efficiency should take into account of energy storage and heat extraction. In this paper we present a review of engineering literature on these two related topics: energy storage with special focus on thermally activated building systems (TABS) as the example of energy storage; heat extraction with the idea of homeostasis providing the context in the application of heat extraction. TABS combines the advantage of radiant surface heating and cooling and the utilization of building structure as thermal energy storage. This proved to be a critical step. This critical review argues that the hydronic circuit for radiant surface cooling offers the necessary element for extracting heat from indoor, thus, makes it possible for combining radiant conditioning, energy storage, and general practice of heat extraction—the resulting synergy of which will be called homeostasis in buildings.
Vaginal reconstruction following supra-levator total pelvic exenteration.

Background. There are several available techniques for neovaginal reconstruction following exenterative gynecologic surgery. However, all methods are associated with prolonged operative time and increased morbidity. The Apogee and Perigee™ vaginal vault and prolapse repair systems are innovative and minimally invasive procedures that may prove to be effective in controlling the levator defect and reconstructing the vagina in patients undergoing supra-levator pelvic exenteration. Case. We present a patient who underwent supra-levator total pelvic exenteration for treatment of recurrent squamous cell carcinoma of the cervix. Vaginal reconstruction was performed with the Apogee and Perigee systems utilizing the porcine mesh (InteXen) from American Medical Systems. The patient did well without any postoperative vaginal or small bowel complications. Conclusion. The Apogee and Perigee systems comprise an innovative technique for vaginal vault reconstruction and prolapse repair. These systems may prove useful in reconstruction of the pelvis following ultra-radical pelvic procedures for recurrent gynecologic malignancies.
Consideration of external events in the individual plant examination program

Abstract In 1985, the Commission issued a severe accidents policy statement which concluded that existing plants pose no undue risk to the public health and safety. However, the Commission recognized that systematic examinations are beneficial in identifying plant-specific vulnerabilities to severe accidents and called for such an examination. As part of the implementation of the Severe Accident Policy, the Commission issued Generic Letter 88-20 in 1988, requesting that each licensee conduct an individual plant examination (IPE) for internally initiated events including internal flooding. Many PRAs have indicated that the risk from external events could be a significant contributor to the core damage in some instances. However, the examination for externally initiated events is being carried out on a later schedule to allow the staff to: (1) identify which external hazards need a systematic examination, (2) identify acceptable examination methods and develop procedural guidance, (3) coordinate with other ongoing external event programs, and (4) conduct a workshop to explain the IPEEE process and to obtain comments and questions on the IPEEE program. The staff has completed its work and has prepared supplement 4 to Generic Letter 88-20 describing the objectives, scope, and schedule of the individual plant examination for external events (IPEEE) and the acceptable methods of examination. The staff also prepared a detailed guidance document, NUREG-1407, on the conduct of the IPEEE and on the structure and the content of the IPEEE submittal. This paper provides a brief discussion of the Supplement 4 to Generic Letter 88-20 and NUREG-1407.
Health Care in America, and Everywhere Else: A Review Essay

Max J. Skidmore analyzes the history of health care policies in America, and reviews T. R Reid's (2009) The Healing of America: A Global Quest for Better, Cheaper, and Fairer Health Care.
Occurrence, plausibility, and desirability for 124 Life Events Inventory items.

Imagination inflation is where imaginative elaboration of possible childhood experiences inflates (increases) participants’ estimation that these events actually occurred, as indicated by pre- to post-manipulation ratings changes. This research primarily uses the Life Events Inventory (LEI), listing possible experiences that could have happened during childhood (Garry, Manning, Loftus, & Sherman, Psychonomic Bulletin & Review, 3, 208–214, 1996). Although imagination inflation research has spawned more than 50 investigations, no normative ratings exist on individual items contained in the LEI. To address this, we present descriptive statistics (mean, median, standard deviation, confidence interval) for 124 LEI items on occurrence (how likely is it that this experience happened to you), plausibility (how plausible is it that this event could have happened to someone), and desirability (how desirable is this experience). Occurrence and plausibility showed similar patterns of mean item ratings and were highly correlated, whereas desirability was moderately correlated with plausibility and unrelated to occurrence. These data should facilitate a more informed selection of specific LEI items to use in further research and can assist in clarifying the contributions of normative occurrence, plausibility, and desirability to imagination inflation effects.
Urothelial Biomechanics: Submucosal Sensing of Intravesical Pressure

Measurement of physiological pressures is fundamental to many forms of medical diagnosis and monitoring in the cardiovascular, respiratory, gastrointestinal, urological and other systems. Pressure is usually measured via catheters, either connected to transducers outside the body or more recently by micro-transducers mounted on the tip of such catheters. However, this requires that the catheters be inserted and maintained without infection and that the patient be tethered to a recording device. While this may be manageable during short term tests such as urodynamics, the measurement of bladder pressure to diagnose incontinence, chronic monitoring poses an additional set of obstacles.Copyright © 2008 by ASME
Immune-mediated Mechanisms in the Pathoprogression of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease with selective loss of upper and lower motor neurons. At sites of motor neuron injury, neuroinflammation is a prominent pathological finding and is characterized by microglial activation, astrogliosis, and infiltration of monocytes and T-cells. Both innate and adaptive immune responses actively influence disease progression in animal models and in ALS patients, and promote neuroprotection or neurotoxicity at different stages of disease. The early immune reaction to signals from injured motor neurons is to rescue and repair damaged tissue. As disease accelerates, a shift occurs from beneficial immune responses (involving M2 microglia and regulatory T-cells) to deleterious immune responses (involving M1 microglia and Th1 cells). In this review, we underscore the importance of immune-mediated mechanisms in the pathogenesis of ALS and discuss the alterations and distinct phenotypes of immune cells at the different stages of disease. The better we understand the dynamic changes that occur within the immune system over the course of disease, the better we will be able to develop effective therapeutic regimens in ALS.
Taking the Distance out of Education

This concluding chapter articulates the philosophical dilemmas we face as a culture and how these must be dealt with in light of our educational models.
Modeling the Catalytic Site of Vanadium Bromoperoxidase: Synthesis and Structural Characterization of Intramolecularly H-bonded Vanadium(V) Oxoperoxo Complexes, [VO(O2)(NH2pyg2)]K and [VO(O2)(BrNH2pyg2)]K

Vanadium haloperoxidases (VHPO) catalyze the peroxidative halogenation of organic substrates. Crystallographic studies suggest that hydrogen bonding from a lysine side chain to the vanadium(V)-bound peroxo group may facilitate oxidation of halides (Cl-, Br-, I-). A ligand with pendant NH2 functionality, N-(2-pyridylmethyl-6-amino) iminodiacetic acid (H2NH2pyg2·2HCl) has been designed to explore the effects that H-bonding from Lys may have on peroxide activation. The first structural characterization of VBrPO model complexes [VO(O2)(NH2pyg2)]K and [VO(O2)(BrNH2pyg2)]K which demonstrate direct intramolecular H-bonding between an amine functionality and V(V)-bound peroxide is reported. The distances between NH2 proton and bound peroxo moiety {(d(N(1)−H···O): 2.637(4) A in [VO(O2)(NH2pyg2)]K, and 2.640(8) and 2.6919(8) A in [VO(O2)(BrNH2pyg2)]K} are indicative of intramolecular H-bonding. The intramolecular H-bond strength in [VO(O2)(BrNH2pyg2)]- is estimated at 6 kcal/mol by 1H NMR studies and demonstrates ...
Theoretical effects of surface diffused region lifetime models on silicon solar cells

A computer simulation of silicon solar cells has indicated that the combination of band gap reduction due to heavy doping and certain spatial forms of lifetime dependence can combine to form severe limitations on the open-circuit voltage of such cells. The interaction of these effects tends to shift the active region of the diffused surface layer away from the injecting junction, resulting in an increase in the current density injected into the surface region. Reductions in open circuit voltage as great as 10% over models which do not include these effects can be seen.
Planning, justifying and installing advanced manufacturing technology: a managerial framework

Purpose – The purpose of this paper is to present the results of an investigation of advanced manufacturing technology (AMT) implementation practices and performance at 82 discrete‐parts durable goods manufacturing plants in the USA.Design/methodology/approach – A mail survey was used to gather information about: the types of AMT that the plants were using; the planning, justification and installation activities that were used to support the adoption of these technologies; and changes in plant performance that could be attributed to the AMT adoptions. Several propositions that were derived from the AMT literature are tested.Findings – Our results indicate that firms that are desirous of adopting integrated technologies should be prepared to exert considerable effort on: fostering a supportive planning environment; integrating investment justification; engendering human and technology resource consistency; and promoting team‐based project planning and installation. Additionally, our analysis indicates that...
Phenomenology of soil erosion due to rocket exhaust on the Moon and the Mauna Kea lunar test site

[1] The soil-blowing phenomena observed in the Apollo lunar missions have not previously been described in the literature in sufficient detail to elucidate the physical processes and to support the development of physics-based modeling of the plume effects. In part, this is because previous laboratory experiments have used overly simplistic model soils that fail to produce many of the phenomena seen in lunar landings, some of which therefore went unrecognized. Here, the Apollo descent videos, terrain photography, and ascent videos are interpreted with the assistance of field experiments using a more complex regolith. Rocket thruster firings were performed upon the tephra of a lunar test site on Mauna Kea in Hawaii. This tephra possesses embedded rocks, large fractions of gravel and dust, some cohesion, and natural geological lamination. This produced more realistic plume phenomenology. The relevant phenomena include the relationship of dust liberation with overall soil erosion rate, terrain bed forms created by the plume, dust tails associated with the exhumation and blowing of rocks, bed load transport, the removal of discrete layers of soil hypothesized to be the stratigraphic units corresponding to impact events, the total mass of ejected soil during a landing, and the brightening of the regolith around the landing site. This analysis provides insight into the erosion processes and nature of the regolith. This paper also synthesizes theory, experiment, simulation, and observational data to produce a clearer picture of the physical processes of lunar soil erosion.
Heuristic algorithm for determining optimal gate and vent locations for RTM process design

In the resin transfer molding (RTM) process, locations of gates and vents are important design parameters that have a great impact on the resin flow pattern and mold filling time. The resin flow pattern is crucial to the quality and properties of the final product. A good resin flow pattern can cover all dry areas in the mold with liquid resin; whereas, a poor flow pattern will lead to some dry spots, which directly result in defects. In this paper, a single gate, multiple vents location problem for 2-D RTM process design is formulated as an optimization model. A process performance index is introduced as the objective function to evaluate the flow pattern in a 2-D RTM process. The authors introduce the concept of general distance between any two locations within the mold. To avoid forming dry spots during the process, all potential vents are determined once a gate is given. A two-phase optimization method, called a graph-based two-phase heuristic (GTPH), is used to find the appropriate locations of the gate and associated vents. The results are compared with those from other methods such as genetic algorithms.
Child-Onset Idiopathic Seizures and Specific Learning Disability: Comorbidities in Adults

In this study, neuropsychological test data and demographic information were collected from 267 adults participating in evaluations as part of their involvement with a Vocational Rehabilitation service. Specifically targeted in this research was an assessment of the comorbidity and character of specific learning disabilities (LD) among individuals with a history of idiopathic seizures. Most participants were found to have reduced general cognitive performance. Persons with seizures performed more like LD adults than a control group of adults with non-seizure-related physical disabilities. This was true for many in the seizure group even when no prior LD had been diagnosed. Specific LDs were found in roughly one-third of adults with seizures. An analysis of diagnostic accuracy was conducted revealing higher than expected rates of Type I and Type II errors for persons who had previously carried an LD diagnosis. Strengths and limitations of the study were discussed along with a particular focus on implicatio...
Approximation algorithms for minimizing segments in radiation therapy

Intensity modulated radiation therapy (IMRT) is one of the most effective modalities for modern cancer treatment. The key to successful IMRT treatment hinges on the delivery of a two-dimensional discrete radiation intensity matrix using a device called a multileaf collimator (MLC). Mathematically, the delivery of an intensity matrix using an MLC can be viewed as the problem of representing a non-negative integral matrix (i.e., the intensity matrix) by a linear combination of certain special non-negative integral matrices called segments, where each such segment corresponds to one of the allowed states of the MLC. The problem of representing the intensity matrix with the minimum number of segments is known to be NP-complete. In this paper, we present two approximation algorithms for this matrix representation problem. To the best of our knowledge, these are the first algorithms to achieve non-trivial performance guarantees for multi-row intensity matrices.
Experimental Analysis of Thermal Cycling Fatigue of Four-Layered FR4 Printed Wiring Boards

Long-term reliability of electronic packaging has become a greater challenge as a result of ever increasing power requirements and the decreasing size of electronic packages. In this study, the effects of three variables on plated-through hole (PTH) design have been investigated on the thermal cycling fatigue lives in four-layered printed wiring boards (PWB’s). These three variables were evaluated at two levels each: (a) hole size (0.030 and 0.040 in.), (b) internal pad (presence or absence), and (c) epoxy-plugged holes (plugged or unplugged). The electrical resistance was measured on 40 test boards with 23 design of 8 daisy-chain PTH nets each. Full factorial analysis and analysis of variance indicate that all three factors had significant influence on PTH fatigue life, but no two-factor or three-factor interactions were found. Metallurgical analysis reveals that the failure mechanism is barrel cracking near the internal pad. This mechanism has been illustrated by a finite element analysis in this study and correlated by a SEM stereoimaging analysis in the literature. The increase of electrical resistance with thermal cycles correlates well with an analytical barrel crack model. The crack length in each net at specific cycles is calculated, but fails to match predictions from a fracture mechanics model.
The American Experience of Religious Disestablishment and Pluralism

EnglishIn 1791, the Founding Fathers of the United States added the First Amendment to the Constitution saying that the nation would have no established religion. This was a new experiment in Churc...
MATLAB as an econometric programming environment

1. INTRODUCTIONProgrammingcomputerstoperformnewlypublishedeconomictechniquesisbecoming moreandmore common for econometricians and economists. The traditional ‘black box’ statisticalpackages simply do not keep up with the most recent advances in the econometrics and statisticsliterature, nor do they o•er the ﬂexibility that most econometricians need and appreciate. Inaddition, a number of econometric tools for data analysis require some programming. A goodexample is the bootstrap, where pseudo-samples are drawn from a data set in order to assess theaccuracy of estimates and design improved tests. The question then becomes: which program-ming language best suits the needs of econometricians and economists? There is no easy answerto this question. The answer depends on a number of factors, including personal tastes and thespeciﬁc problems to be solved. This article provides an overview of a high-level matrix program-ming language with graphical implementations that is being increasingly used by economists:MATLAB.2. OVERVIEW2.1. GeneralMATLAB (short for ‘Mathematics Laboratory’) is a high-level matrix programming languagethat grew out of the LINPACK and EISPACK matrix algorithm projects. Originally written inFortran, MATLAB is now written in C and commercially developed by The MathWorks, Inc(24 Prime Park Way, Natick, MA 01760-1500 USA, phone: (508) 746-7000, fax: (508) 647-4101,e-mail: info@mathworks.com, Web page: http://www.mathworks.com). In addition toCCC 0883–7252/97/060735–10$17.50 Received 23 May 1997#1997 John Wiley & Sons, Ltd.
Coupled Electron and Proton Transfer in Complex I and Complex IV of the Respiratory Chain: Insights from Computer Simulations

I will discuss coupled transport of electrons and protons in two key enzymes of the electron transport chain of aerobic cells: NADH dehydrogenase (Complex I) and cytochrome c oxidase (Complex IV), which are, respectively, the entry point, and the terminal enzyme in the respiratory chain.Computer simulations and theoretical modeling of ET/PT reactions in these enzymes provide important insights into the molecular mechanisms of these redox-driven proton pumps.
The Association of Religiosity, Sexual Education, and Parental Factors with Risky Sexual Behaviors Among Adolescents and Young Adults

This study examined the association of religiosity, sexual education and family structure with risky sexual behaviors among adolescents and young adults. The nationally representative sample, from the 2002 National Survey of Family Growth, included 3,168 women and men ages 15-21 years. Those who viewed religion as very important, had frequent church attendance, and held religious sexual attitudes were 27-54% less likely to have had sex and had significantly fewer sex partners than peers. Participants whose formal and parental sexual education included abstinence and those from two-parent families were 15% less likely to have had sex and had fewer partners.
Growth and Physical Performance of American Negro and White Children A Comparative Survey of Differences in Body Size, Proportions and Composition, Skeletal Maturation, and Various Motor Performances

Adults of different racial or ethnic groups vary in size and proportional measures, and one may assume that these differences become apparent early in the human growth cycle. Hence it is important to ascertain when during the growth period such differences become readily recognizable, and how they are related to rates of growth, growth gradients and biologic maturation.
Outcomes following cholecystectomy in pregnant and nonpregnant women.

Backgr-ound. This study is the first population-based measurement of outcomes after cholecystectomy during pregnancy. Methods. We identified all pregnant women who underwent cholecystectomy in the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample, 1996-2006. Outcomes were fetal, maternal, and surgical complications, length of stay (LOS), and hospital cost. Pregnant and nonpregnant women were compared to examine the effects of pregnancy on laparoscopic cholecystectomy outcomes. Results. A total of 9,714 pregnant women underwent cholecystectomy (laparoscopic, 89%). Maternal and fetal complication rates were 4.3% and 5.8%, respectively. Pregnant women who underwent laparoscopic cholecystectomy compared to pregnant women who underwent open procedures had higher rates of surgical (19 % vs 10 % ), maternal (9 % vs 4 %), and fetal (11 % vs 5 % ) complications; longer LOS (6 vs 4 days); and higher cost ($13,198 vs $9,229), all P < .0001. High-volume surgeons were associated with lower rates of surgical (10 % vs 13 %; P < .05), maternal (1 % vs 14 % ), and fetal (4% vs 10%) complications; shorter LOS (4 vs 5 days); and lower cost ($8,365 v.s $10,350), all P < .0001. Patients with Medicaid coverage were associated with higher rates of surgical complications (13 % vs 9 % ), longer LOS (4.3 vs 3. 7 days), and higher cost ($10,403 vs $9,037), all P < .0001. On multivariable analysis, these factors remained independent predictors of outcome. Pregnancy was associated with longer LOS and higher cost. Conclusion. Complications of cholecystectomy during pregnancy are significant, with disparities based on modifiable variables.
An optimal varentropy bound for log-concave distributions

A sharp uniform bound is obtained for the varentropy of the class of log-concave distributions. In particular, this yields the optimal strengthening of the equipartition property for such distributions recently proved by Bobkov and the first-named author.
Diurnal patterns of size-fractioned primary productivity across a coastal front

In July 1985, diurnal patterns of photosynthesis and pigmentation were characterized for whole water (>0.4 μm) and size-fractioned (>5 μm and 0.4 to 5 μm) communities from three light depths sampled across a coastal thermal front in the Southern California Bight. Samples were collected predawn and held for 20 h in deck incubators. Variations in chlorophyll a and accessory pigment-to-chlorophyll a ratios showed no obvious diurnal trends. Timing of peak photosynthetic potential (P max) and its coincidence with variations in light-limited rates of photosynthesis (alpha), as well as diurnal amplitudes in P max and alpha, often differed between size fractions sampled within the same community. The same was true for identical size fractions collected from different depths and stations transecting the front. Primary productivity was 20-fold greater on the cold water side, where >5 μm diatoms dominated the mixed layer and accounted for 80% of daytime productivity. Diatoms collected from the top and bottom of the upper mixed layer displayed nearly identical diurnal patterns in P max and alpha, with midday peaks exceeding predawn values by four-fold and two-fold respectively. Above the pycnocline, the 0.4 to 5 μm fraction had lower assimilation rates than the >5 μm fraction and smaller diurnal amplitudes in P max and/or alpha, with daytime patterns often characterized by two peaks interspersed by a short period of photoinhibition. Within the front, the 0.4 to 5 μm fraction accounted for two-thirds of plant biomass and >90% of primary production. Pigment analyses by high-performance liquid chromatography revealed enrichment in 19′-hexanoyloxyfucoxanthin, indicative of enhanced numbers of prymnesiophtes. Photosynthetic activity in confined surface communities was susceptible to daytime photoinhibition, but subsurface communities exhibited midday P max peaks that were three-to seven-fold predawn values. In the warm-water mass, both algal size fractions contributed equally to photosynthesis and chlorophyll a in surface waters, with the 0.4 to 5 μm fraction becoming dominant at the base of the euphotic zone. At all depths, peak P max of the 0.4 to 5 μm fraction occurred before noon, while P max of the >5 μm fraction was clearly evident in the afternoon. Elevated chlorophyll b-, 19′hexanoyloxyfucoxanthin- and zeaxanthin-to-chlorophyll a ratios indicated a mixture of algal groups, including chlorophytes, cyanobacteria and prymnesiophytes.
Education and Colonialism . Edited by Philip G. Altbach and Gail P. Kelly. New York: Longman, 1978. ix, 372 pages. Notes, Selected Bibliography. $6.95 (paper).

Education and Colonialism is a symposium of articles dealing with the educational experiences of some formerly colonized peoples and other oppressed groups. The major objective of the editors is to substantiate their claim that the framework of classical colonialism can be useful in studying education, not only in colonized societies, but also among other exploited, oppressed or disadvantaged groups in any society.
Combining Symbolic and Neural Learning

Connectionist machine learning has proven to be a fruitful approach, and it makes sense to investigate systems that combine the strengths of the symbolic and connectionist approaches to AI. Over the past few years, researchers have successfully developed a number of such systems. This article summarizes one view of this endeavor, a framework that encompasses the approaches of several different research groups. This framework (see Figure 1) views the combination of symbolic and neural learning as a three-stage process: (1) the insertion of symbolic information into a neural network, thereby (partially) determining the topology and initial weight settings of a network, (2) the refinement of this network using a numeric optimization method such as backpropagation, possibly under the guidance of symbolic knowledge, and (3) the extraction of symbolic rules that accurately represent the knowledge contained in a trained network. These three components form an appealing, complete picture—approximately-correct symbolic information in, more-accurate symbolic information out—however, these three stages can be independently studied. In conclusion, the research summarized in this paper demonstrates that combining symbolic and connectionist methods is a promising approach to machine learning.
14C2H4: Its Incorporation and Metabolism by Pea Seedlings under Aseptic Conditions

The effects of various treatments on the recently reported system in pea ( Pisum sativum cv. Alaska), which results in ( a ) the incorporation of 14 C 2 H 4 into the tissue and ( b ) the conversion of 14 C 2 H 4 to 14 CO 2 , was investigated using 2-day-old etiolated seedlings which exhibit a maximum response. Heat treatment (80 C, 1 min) completely inhibited both a and b , whereas homogenization completely inhibited b but only partially inhibited a . Detaching the cotyledons from the root-shoot axis immediately before exposing the detached cotyledons together with the root-shoot axis to 14 C 2 H 4 markedly reduced both a and b . Increasing the 14 C 2 H 4 concentration from 0.14 to over 100 μl/l progressively increased the rate of a and b with tissue incorporation being greater than 14 C 2 H 4 to 14 CO 2 conversion only below 0.3 μl/l 14 C 2 H 4 . Reduction of the O 2 concentration reduced both a and b , with over 99% inhibition occurring under anaerobic conditions. The addition of CO 2 (5%) severely inhibited 14 C 2 H 4 to 14 CO 2 conversion without significantly affecting tissue incorporation. Exposure of etiolated seedlings to fluorescent light during 14 C 2 H 4 treatment was without effect. Similarly, indoleacetic acid, gibberellic acid, benzyladenine, abscisic acid, and dibutyryl cyclic adenosine monophosphate had no significant effect on either a or b . The possibilities that the incorporation of 14 C 2 H 4 into pea tissues and its conversion to 14 CO 2 is linked to ethylene action, or that it represents a means of reducing the endogenous ethylene level, are discussed. Several problems encountered with the use of polyethylene vials, rubber serum stoppers, Clorox, and microbial contamination are also described.
The Optimal Duration of Real Estate Listing Contracts

The length of the real estate listing contract is examined as a means of providing an incentive for brokers to act in the best interest of home sellers. A limitation on the duration of the contract accomplishes this objective by imposing a cost (namely, the foregone commission) on brokers who fail to complete a sale before the contract expires. The seller's optimal contract duration balances the benefits of improved incentives against the expected cost of renegotiating a new contract in the event of a failure bv the broker.
L-proline and related compounds: Correlation of structure, amnesic potency and anti-spreading depression potency

The effects of L-proline, D-proline, and L-azetidine-2-carboxylic acid (L-A.2.C., the lower homolog of L-proline) have been compared in two systems. L-Proline is more potent than either analog in causing amnesia of one-trial avoidance conditioning of the 2-day-old chick and in preventing mechanically induced spreading depression in the retina isolated from 2-3-week-old chicks. The results suggest that the L-configuration and the proper molecular size are essential for the effects of L-proline upon memory and upon spreading depression. This level of specificity is greater than that involved in protein synthesis because L-A.2.C. is incorporated into protein in place of L-proline, in several protein-synthesizing systems.
Effects of Population Density and Pack Size on the Foraging Ecology of Gray Wolves

A decline in the gray wolf ( Canis lupus ) population in Isle Royale National Park prompted an intensive study of radiocollared individuals in 1988–1991, complementing an ongoing study begun in 1958. During winter, 1959–1991, the proportion of lone wolves was higher when the population was at low levels, whereas average size of packs declined with density of wolves. Sizes of territories (1971–1991) were not related to size of packs. In winter, food availability (kg wolf−1 day−1) and kill interval (days/kill) varied inversely with size of packs. Social relationships of radiocollared lone wolves were flexible; they often formed temporary groups of two or three wolves. Small groups (less than four) and lone wolves roamed large areas of the island (300 km2 and 540 km2, respectively), frequently moving through territories of established packs. Solitary wolves and pairs readily killed adult moose, in contrast to a common belief that larger packs benefit from cooperative hunting.