cssi/SciSciGPT-SciSciNet huggingface dataset:
A Dynamical Supervisor Strategy for Multi-Product Processes

Competing in the global marketing place puts additional burden on multi-product manufacturing processes. Each transition to a different product grade must be made efficiently with the simultaneous objectives of minimal off-spec product and feed stock waste, and non-violation of safety and environmental constraints. In this work, a hybrid, dynamical supervisory control strategy is presented to address transition control of multi-product processes. The scheme involves the selection of the best setpoint controller, from an existing family of feedback controllers so as to cause the output to track the desired setpoint. The performance of the supervisory control strategy is demonstrated on an exothermic reactor.
Around the traps: a reappraisal of stone fishing weirs in northern New South Wales

changes was the more intensive occupation of some marginal areas (eg. Bowdler 1981; Flood 1980) which is only considered to have been possible after these developments in resource procurement had evolved. A related element of these changes was the development of new resource management techniques and technologies. These included rendering poisonous foods edible through leaching, stabilizing the availability of a resource, increasing the yield of a particular food per unit area or decreasing the labour required to obtain a given amount of a resource, all of which were aimed at increasing the productivity of a region (eg. Beaton 1977; Hallam 1975; Lourandos 1980b). Amongst these technological innovations was the establishment of new facilities, such as large hunting nets, fishing weirs1 and, probably the most frequently cited of all, the Toolondo eel traps (described by Lourandos 1980a, 1980b). It has been suggested that these facilities and other technological developments ensured the large amount of food necessary to sustain increased populations, the expanded cycle of ceremonial activity, and the attendant changes in settlement patterns which some prehistorians have argued took place during the late Holocene in Australia (eg. Lourandos 1980a; Bowdler 1981; Ross 1985; Morwood in press). However attractive these arguments seem, it is necessary that they have not only a well-developed theoretical structure such as Lourandos has cogently advanced in a series of papers (1980a, 1980b, 1983, 1984, 1985a, 1985b; cf. Beaton 1983, 1985), but an empirical base that can stand rigorous review. Thus it is crucial that the age and origin of facilities such as eel traps and fishing weirs are established before such structures can be included in the corpus of data used to sustain these models. Lourandos (1980a) recognised this when considering the Toolondo eel traps and before relating their construction to changing social and environmental circumstances in southwest Victoria, the first demonstrated their antiquity and Aboriginal origin. Coleman (1978, 1982:9) has presented a model for the north coast of NSW which involves a major reorientation of settlement patterns in this region about 2500 years ago. In this model there was at that time a shift from a heavy reliance on an estuarine resource base to an economy in which the richly-endowed littoral zone played a more prominent part. Whatever the cause of this, people were lead to settle at various places along the coast in villages, near which they
Conjugate addition reactions of organocuprates derived from α- aminoalkyl carbanions

Abstract α-Aminoalkyl carbanions derived from formamidine derivatives afford higher order cyanocuprate reagents (R 2 CuCNLi 2 ) that undergo 1, 4-addition reactions to α,β-enones.
Insulin Resistance, Elevated Glomerular Filtration Fraction, and Renal Injury

The development of insulin resistance may be an early step in the development of hypertension; however, the mechanism for this process is not known. The worsening of insulin resistance and hyperten...
Toughening Behavior in Whisker-Reinforced Ceramic Matrix Composites

The toughening behavior of whisker-reinforced ceramics is analyzed in terms of a whisker bridging zone immediately behind the crack tip. This approach is consistent with microscopy observations which reveal that intact bridging whiskers exist behind the crack tip as a result of debonding of the whisker-matrix interface. The theoretical results based on both the stress intensity and the energy change introduced by bridging whiskers reveal the dependence of toughening upon the composition and matrix, interface, and whisker properties. Furthermore, the analytical models of whisker bridging accompanied by very limited pullout accurately describe experimental observations of the toughening behavior in several SiC-whisker-reinforced ceramics. Such analytical descriptions also indicate that increases in whisker size and strength and modification of interface properties will result in further increases in toughness by whisker reinforcement.
Sequential detection between Poisson processes (Corresp.)

The problem of sequential detection between Poisson processes is analyzed and resolved. Wald's results on sequential analysis are used, but a substantial modification is shown to be necessary due to the discontinuous nature of the likelihood ratio. It is shown that, in general, one can take into account the "excess over the boundary" so as to design sequential tests with a given error performance.
A Simple Evaluation of Anterior Cruciate Ligament Femoral Tunnel Position The Inclination Angle and Femoral Tunnel Angle

Background: Postoperative determination of tunnel position after anterior cruciate ligament (ACL) reconstruction can be challenging.Hypothesis: The femoral tunnel angle and inclination angle are reliable methods for evaluating tunnel position after ACL reconstruction while aiding in determining whether an ACL reconstruction falls outside an anatomic range as defined on 3-dimensional (3D) computed tomography (CT).Study Design: Cohort study (diagnosis); Level of evidence, 3.Methods: Fifty patients were included who received single-bundle ACL reconstructions with postoperative flexion weightbearing radiographs, magnetic resonance imaging (MRI), and CT scans. Femoral tunnel angles were determined from posterior-to-anterior postoperative radiographs, and inclination angles were determined from sagittal MRI. The ACL reconstructions were grouped by surgical technique, transtibial (TT) or tibial tunnel independent (TTI), and as either falling inside or outside an anatomic range on 3D CT.Results: Patients with tun...
Endstage renal disease owing to diabetic nephropathy in Mississippi: an examination of factors influencing renal survival in a population prone to late referral.

Background Diabetic nephropathy (DN) is the leading cause of endstage renal disease (ESRD) in the United States. We reviewed our experience with DN as a cause of ESRD in a predominantly poor, African American (AA) population. Methods Charts of patients who entered the ESRD program through the University of Mississippi Medical Center with a primary diagnosis of DN from 1993 through 1998 were reviewed for factors that may affect renal survival. Time from initial clinic visit to entry into the ESRD program, or time to ESRD (TTE), was the primary end point. Results Five hundred sixty-two patients entered the ESRD program (85% AA), and 210 of them had DN as their primary ESRD diagnosis. DN accounted for 50.5% of ESRD cases among AA females, but for less than 20% among AA males. In contrast, hypertension was the ESRD diagnosis in 48% of AA males. Patients observed in our nephrology clinic were analyzed further (n=171). At presentation, patients had advanced disease (serum creatinine [Cr]=5.92 mg/dL), were hypertensive, obese, and not likely to be on an angiotensin-converting enzyme (ACE) inhibitor. Determinants of TTE in univariate analysis were race (AA did better), initial blood urea nitrogen and plasma serum Cr levels, starting an ACE inhibitor at the University of Mississippi Medical Center, and the level of mean arterial pressure (MAP) during the course of follow-up. On multivariate analysis only initial Cr and race remained significant. The 142 AA diabetics (111 female) were analyzed separately. The only significant sex difference was body mass index (female, 33.6 vs male, 28.4 kg/m2; P=0.0069), but females tended to have relatively shorter TTE and higher blood pressure (BP). Univariate and multivariate analyses revealed the same factors as above as determinants of TTE; however, among AAs, presenting on a calcium channel blocker was negatively correlated with TTE in univariate analysis. Among the entire cohort and the AAs, patients who had MAP between 100 and 110 mm Hg during the course of follow-up did better in terms of renal survival than those who fell outside of that range. Conclusions We conclude that AA females in Mississippi are significantly more predisposed to DN as a cause of ESRD than are AA males. Patients with DN in our population had poor BP control, presented to nephrologists with advanced disease, and often were not on an ACE inhibitor. The optimal level of BP control and which BP agents are best for this population need to be determined.
Further Remarks on Maximum Likelihood Estimators for the Gamma Distribution

The maximum likelihood estimators , â, for the parameters ρ, a of the gamma density f(x) = k(x/a)ρ–1 exp(−x/a) are solutions of the equations In – ψ() = ln(A/G), â = A, where Ψ is the logarithmic derivative of the gamma function, A and G being the sample (of size n) arithmetic and geometric means, respectively. The moments of and â are developed in descending powers of ρ. A comparison of the assessments of the moments by the present approach and a method involving series in descending powers of n is made. Approximate expressions are also given for the first four moments of ĉ = l/â, which is the maximum likelihood estimator of c = l/a.
Carpal Kinematics During Simulated Active and Passive Motion of the Wrist

Purpose The purpose of this study was to investigate the effect of experimental control mechanisms, simulated active (tendon-driven) and passive (externally assisted), on carpal motion. Methods Kinematics of the carpal bones in five fresh-frozen cadaver upper extremities were studied using an optical motion analysis system. The wrist extensors and flexors were dissected and loaded. For passive motion, the tendons were loaded to simulate muscle tone while the investigator passively moved the wrist using a pin placed in the third metacarpal. To simulate active, patient-driven motion, the tendons were attached directly to guide bars while the investigator used a puppeteer mechanism to move the wrist. Results There were no significant differences in carpal motion (flexion-extension motion or radial-ulnar deviation) when the wrist was moved in simulated active motion through the extensor and flexor tendons or in passive motion, with a constant force applied to the tendons. Kinematics for simulated active motion, in general, was more difficult to control and was less smooth than the kinematics for passive motion. Conclusions Carpal bone kinematics (excluding the pisiform) in a healthy normal joint are similar in both simulated active (tendon-driven) and passive (externally assisted) wrist motion because the carpal bones are passively moved during wrist motion (there are no direct tendon-to-muscle attachments to the proximal carpal bones and minimal attachments to the distal carpal bones).
Risk factors for clinically relevant pulmonary embolism and deep venous thrombosis in patients undergoing primary hip or knee arthroplasty

BackgroundPrevention of thromboembolic complications after elective lower extremity arthroplasty has increasingly relied on routine thromboprophylaxis in all patients. Not all patients are at equal risk, however, and prophylaxis is not devoid of complications. The aim of this study was to examine th
Extended Hildebrand Solubility Approach: p -Hydroxybenzoic Acid in Mixtures of Dioxane and Water

Abstract The extended Hildebrand solubility approach was used to reproduce the solubilities of p -hydroxybenzoic acid in a dioxane–water system. The solubility parameter of p -hydroxybenzoic acid was determined and found to be ~ 15 (cal/cm 3 ) 1/2 . Residual plots (scattergrams) were used in conjunction with R 2 , F , and standard deviation values to determine whether a quadratic, cubic, quartic, or higher degree polynomial was required in the calculations. The earlier iteration method for back-calculations of solubilities was replaced by the more reliable root-finder method 1 . The solubility profile of p -hydroxybenzoic acid in dioxane–water mixtures did not follow a log linear relationship even in the ranges where the solubility parameters of the water–cosolvent mixture might be expected to produce a straight-line function, as observed in other studies.
Light absorption from particulate impurities in snow and ice determined by spectrophotometric analysis of filters

Light absorption by particulate impurities in snow and ice can affect the surface albedo and is important for the climate. The absorption properties of these particles can be determined by collecting and melting snow samples and extracting the particulate material by filtration of the meltwater. This paper describes the optical design and testing of a new instrument to measure the absorption spectrum from 400 to 750 nm wavelength of the particles collected on filters using an “integrating-sandwich” configuration. The measured absorption is shown to be unaffected by scattering of light from the deposited particulates. A set of calibration standards is used to derive an upper limit for the concentration of black carbon (BC) in the snow. The wavelength dependence of the absorption spectra from 450 to 600 nm is used to calculate an absorption Ångstrom exponent for the aerosol. This exponent is used to estimate the actual BC concentration in the snow samples as well as the relative contributions of BC and non-BC constituents to the absorption of solar radiation integrated over the wavelength band 300 to 750 nm.
Initial Quality of Life (QOL) Deficit Is Related to Decreased Survival in Esophageal Cancer (EC): Final Report of 840 Consecutive Patients Prospectively Evaluated by the Single-Institutional Romero Registry

Results: A total of 898 patients were included. At 2 years, we had data for over 94% of patients. At the early time point 54% of patients had a change in QOL summary that was a MDD or greater for bowel, 37% for urinary incontinence, 78% for urinary obstruction, and 42% for sexual function. At 2 years, a MDD was noted in 29%, 24%, 36%, and 47% for bowel, urinary incontinence, urinary obstruction, and sexual domains, respectively. For those with less than a MDD at the early time, the proportion with MDD at 2 years was 19%, 15%, 14%, and 31%. On MVA, after controlling for age, baseline QOL, PSA, Gleason score, T-stage, prostate volume, and RT technique, an early MDD was the strongest predictor of MDD at 2 years in all domains: OR Z 2.4 [95% CI Z 1.6-3.5] for bowel, OR Z 4.5 [95% CI Z 2.9-6.9] for urinary incontinence, OR Z 3.7 [95% CI Z 2.2-6.4] for urinary irritation, and OR Z 3.7 [95% CI Z 2.55.5] for sexual function. Conclusions: Early QOL decline was the strongest predictor of QOL impacts at 2 years in all domains across multiple RT treatment types. These data require external validation, but are suggestive that early QOL declines may be a viable surrogate for 2 year QOL in future studies. Author Disclosure: S. Zhao: None. J.R. Evans: None. S. DaignaultNewton: None. M.G. Sanda: None. J. Michalski: None. H.M. Sandler: None. D.A. Kuban: None. J.P. Ciezki: None. I.D. Kaplan: None. A.L. Zietman: None. F.Y. Feng: None. L. Hembroff: None. S. Suy: None. C.A. Mantz: A. Employee; 21st Century Oncology. S. Collins: G. Consultant; Accuray. D.A. Hamstra: None.
Neurotrophins Regulate Sequential Changes in Neurotrophin Receptor Expression by Sympathetic Neuroblasts

We have examined the mechanisms controlling the induction of the two NGF receptors, trkA and p75, in proliferating neuroblasts immuno-isolated from thoracolumbar embryonic sympathetic ganglia. Contrary to prior studies, we find that induction of p75 follows rather than precedes that of trkA; this late induction is consistent with the fact that p75 functions at relatively late stages of sympathetic development. trkA induction is apparently not controlled by a cell-intrinsic mechanism. Rather, this receptor is induced by environmental signals including NT-3, which also acts as an interim survival factor for these neuroblasts, trkA induction by NT-3 is consequent to its promotion of mitotic arrest, as anti-mitotic drugs also efficiently induce trkA. p75 expression is induced in trkA-expressing cells by NGF. Thus, the development of sympathetic neurons involves sequential actions of different neurotrophins, which also regulate the expression of their own and each other's receptors.
A synthesis of the tetramic acid subunit of streptolydigin: A reactivity definition of this subunit as an Emmons reagent

Abstract A practical and brief construction of the tetramic acid-derived Emmons reagent 3 is described. The reactivity of this substance with aldehydes has been examined with respect to its use in a synthesis of the antibiotic streptolydigin.
Who is Shouldering the Burden of Transition? An Analysis of Depreciation Rates in Russian Industry

Did maintaining existing tax codes governing depreciation rates in Russian industry between 1992 and 1995 target particular types of firms to carry a disproportionate share of the burden of transition? Firm-level data collected in 1992 and 1995 are utilized here to assess whether the “engines of transition” - non-state-owned firms, and firms with export experience shouldered a disproportionate share of the burden in the form of below-average depreciation rates and thus an above-average tax burden. The results indicate that ownership and export experience are important explanatory variables in explaining within-industry variation in depreciation rates in 1992. While non-state-owned firms did exhibit below-average depreciation rates in 1992 and thus incurred a higher tax burden, exporters as a category of firms exhibited above-average depreciation rates. Thus, the results are mixed with regard to whether the “engines of transition” shouldered a disproportionate burden. By 1995, the effects of both ownership and export experience on the variation of within-industry depreciation rates diminishes. Regional variation becomes more pronounced in 1995, and tends to coincide the regional variation in the pace of transition.
Dosimetry for 125I seed (model 6711) in eye plaques

The effect of eye plaque materials (gold backing and silastic seed‐carrier insert) on the dose distribution around a single 125I seed has been measured, using cubic lithium fluoride thermoluminescent dosimeters(TLDs) 1 mm on an edge, in a solid water eye phantom embedded in a solid water head phantom. With an 125I seed (model 6711) positioned in the center slot of the silastic insert for a 20‐mm plaque of the design used in the collaborative ocular melanoma study (COMS), dose was measured at 2‐mm intervals along the plaque central axis (the seed’s transverse axis) and at various off‐axis points, both with and without the COMS gold backing placed over the insert. Monte Carlo calculations (MORSE code) were performed, as well, for these configurations and closely the same geometry but assuming a large natural water phantom. Additional Monte Carlo calculations treated the case, both for 20‐ and 12‐mm gold plaques, where the silastic insert is replaced by natural water. Relative to previous measurements taken in homogeneous medium of the same material (without the eye plaque), the dose reduction found by both Monte Carlo and TLD methods was greater at points farther from the seed along the central axis and, for a given central‐axis depth, at larger off‐axis distances. Removal of the gold backing from the plaque did not make measurable difference in the dose reduction results (10% at 1 cm).
L-Tyrosine-3-hydroxylase regulation in the brain: genetic aspects

L-tyrosine-3-hydroxylase (TH) is the first and rate limiting enzyme in the biosynthetic pathway of catecholamine neurotransmitters (dopamine, noradrenaline, adrenaline). Implication of dopamine (DA) in various psychopathological phenomena, such as schizophrenia, has considerably contributed to the intensity of investigation of basic biochemical regulation of TH by activation and induction. Here we consider a third, constitutional (genotypic) aspect of regulation and present evidence that differences in mesencephalic (TH/SN), striatal (TH/CS), and hypothalamic (TH/HT) TH activity between virtually isogeneic strains of mice can be explained by segregating genetic factors. Biometrical genetic analysis of progenitor strains and their crosses indicated significant additive gene effects for TH/SN, TH/CS, and TH/HT, whereas dominance effects were statistically non-significant. A monogenic model of inheritance for TH/SN and TH/CS could not be rejected, while more than one gene was indicated for TH/HT. Significant positive phenotypic correlations were found in genetically segregating populations among mesencephalic, striatal and hypothalamic TH activities. This would suggest that some common genetic factors (or linked genes) are involved in the genetic variation of all three traits. A genetic selection experiment to elucidate the cellular and biochemical mechanisms underlying these variations is in progress.
Leucine treatment enhances oxidative capacity through complete carbohydrate oxidation and increased mitochondrial density in skeletal muscle cells

Leucine has been largely implicated for increasing muscle protein synthesis in addition to stimulating mitochondrial biosynthesis. Limited evidence is currently available on the effects and potential benefits of leucine treatment on skeletal muscle cell glycolytic and oxidative metabolism. This work identified the effects of leucine treatment on oxidative and glycolytic metabolism as well as metabolic rate of human and murine skeletal muscle cells. Human rhabdomyosarcoma cells (RD) and mouse myoblast cells (C2C12) were treated with leucine at either 100 or 500 μM for 24 or 48 h. Glycolytic metabolism was quantified by measuring extracellular acidification rate (ECAR) and oxidative metabolism was quantified by measuring oxygen consumption rate. Peroxisome proliferator-activated receptor coactivator 1 alpha (PGC-1α), an important stimulator of mitochondrial biosynthesis, was quantified using flow cytometry and verified by immunofluorescent confocal microscopy. Mitochondrial content was quantified using mitochondrial and cytochrome C staining measured by flow cytometry and confirmed with confocal microscopy. Treatment with leucine significantly increased both basal and peak oxidative metabolism in both cell models. Leucine treated cells also exhibited significantly greater mitochondrial proton leak, which is associated with heightened energy expenditure. Basal ECAR was significantly reduced in both cell models following leucine treatment, evidence of reduced lactate export and more complete carbohydrate oxidation. In addition, both PGC-1α and cytochrome C expression were significantly elevated in addition to mitochondrial content following 48 h of leucine treatment. Our observations demonstrated few dose-dependent responses induced by leucine; however, leucine treatment did induce a significant dose-dependent expression of PGC-1α in both cell models. Interestingly, C2C12 cells treated with leucine exhibited dose-dependently reduced ATP content, while RD ATP content remain unchanged. Leucine presents a potent dietary constituent with low lethality with numerous beneficial effects for increasing oxidative preference and capacity in skeletal muscle. Our observations demonstrate that leucine can enhance oxidative capacity and carbohydrate oxidation efficiency, as well as verify previous observations of increased mitochondrial content.
Chromosome Studies in the Genus Plasmodium

SUMMARY. A study has been made of the number and morphology of the chromosomes of five species of malarial parasites as seen in living material with phase contrast microscopy. Plasmodium knowlesi, of monkeys, is essentially similar to other primate malarial parasites previously studied, having two chromosomes of unequal length. P. lophurae, from ducks, P. relictum from pigeons and sparrows, and P. floridense from a lizard all have two small chromosomes of equal size. These facts, with ether data, indicate that the genus may consist of two species complexes. P. berghei, studied in white mice and rats, has a karyotype similar to the avian and saurian malarial parasites. The suggestion is made that P. berghei, on a basis of chromosome pattern and other characteristics, is probably more closely related to the avian and saurian species of Plasmodium than to other mammalian species.
Hemoglobin level and risk of hospitalization and mortality in children on peritoneal dialysis

Clinical practice guidelines for management of anemia in children with end-stage kidney disease (ESKD) remain largely opinion-based. In this study, we evaluated the risk of mortality and hospitalization by hemoglobin (Hb) level in a large prevalent population of U.S. children on peritoneal dialysis (PD). Hemoglobin levels in prevalent PD patients from the 2005 End Stage Renal Disease Clinical Performance Measures Project were linked with 5-year mortality and 4-year hospitalization records from the United States Renal Data System. Of the 468 patients included in the study, the mean age was 11 years, 55 % were male, 67 % were white, 254 (54 %) were hospitalized, and 23 (5 %) died. Median (interquartile range) Hb levels were 11.7 (10.7–12.6) g/dl, and 30 % had Hb levels of <11 g/dl. In adjusted survival analysis, Hb thresholds of 10, 11, or 12 g/dl were not associated with a significant difference in risk of death. The incidence rate ratio (IRR) of hospitalization for patients with a mean Hb of ≥11 g/dl was 0.56 (95 % CI 0.43–0.73). Compared to a reference range of Hb of 11 to <12, Hb of ≥12 g/dl was not associated with a significant difference in hospitalization risk (IRR 0.88; 95 % CI 0.61–1.25). Using age- and sex specific cut-offs for anemia, children who were not anemic had a 27 % decreased risk of hospitalization compared to those with anemia (IRR 0.73; 95 % CI 0.55–0.97). Compared to the first erythropoiesis stimulating agent (ESA) dosing quartile, higher ESA doses were associated with an increased risk of both hospitalization and mortality. U.S. children on PD with Hb levels of ≥11 g/dl were less likely to be hospitalized but had no observed difference in mortality. Children who were not anemic were also less likely to be hospitalized. Further study is necessary to elucidate whether a single optimal Hb level or a range applies to the pediatric ESKD population.
Developmental differences in the learning of computer programming: Achievement and relationships to cognitive abilities

Abstract This study investigated the cognitive abilities that predict the learning of off-computer and on-computer components of Logo programming in first and third graders and compared the degree of learning of these children. Twenty-four children learned Logo during two 45- to 50-min sessions for each of 22 weeks. Consonant with previous research, there was no evidence of significant differences between the scores of first and third graders on most components of Logo programming. Third graders did score significantly higher on one component, procedural thinking, possibly due to that task's relatively high information-processing demands. While measures were positively related to most components of Logo programming, these measures were differentially predictive for first and third graders and for different components. Implications of the study for research and education are discussed.
The binding of androgen receptor to DNA and RNA

Abstract The androgen receptor from mouse kidney cytosol has been studied for its nucleic acid binding properties by DNA-cellulose centrifugation assay. The receptor appears to bind to RNA (mRNA, tRNA, rRNA) as well as to DNA. Salt and heat activation of the androgen receptor enhances both DNA and RNA binding. The receptor binds slightly better to denatured DNA than to native DNA. The androgen receptor binds about 2-fold tighter to poly(dG-dC) than to poly(dA-dT). The interaction of the receptor with DNA is not greatly affected by the BrdUrd substitution. The observation that androgen receptor shows a significant affinity to RNA may imply that androgen receptor-RNA interaction could play a role in gene regulation.
In vitro culture of leukocytes from patients with sarcoidosis: in search of an "in vitro Kveim test".

Mononuclear cells from patients with sarcoidosis respond to Kveim tissue suspensions in vivo and form granulomas. We attempted to develop an in vitro Kveim test by adding Kveim material to monocytes and lymphocytes from patients with sarcoidosis and observing the cells in tissue culture. Sarcoid leukocytes were grown in culture with either Kveim suspensions (100 μg/ml), control human spleen extract (100 μg/ml) or no foreign antigen. After 7 to 9 days, we counted the number of cells adherent to glass, the number of cells with nucleoli, and the number of giant cells. Despite equal monocyte inocula, cultures of sarcoid leukocytes consistently had more cells adherent to glass than did cultures from normal donors regardless of whether Kveim, spleen, or no antigen was added to the cultures. There were no significant differences in giant cell formation or in the number of cells with nucleoli in the sarcoid compared with the control cultures.
A Markov Model for the Short-Term Retention of Spatial Location Information.

A Markov model was proposed to account for the short-term retention of the spatial arrangement of letters. The model was fit well to three spatial location recall conditions differing only in distractor task by changing only the one parameter in the model representing the transfer of information from primary memory to secondary memory. Two experiments were conducted which manipulated the temporal—spatial patterns of the items occurring during the distractor task. These experiments provided support for the primary assumption of the model that information is coded about the temporal—spatial patterns of letter presentations and for the classification of those patterns by the model.
What is software testing? And why is it so hard?

The author sheds some light on why testing today's software products is so challenging, and he identifies several solid approaches that all testers should be able to thoughtfully apply. The effective tester has a rich toolkit of fundamental testing techniques, understands how the product will be used in its operating environment, and has a nose for where subtle bugs might lurk in the product and a bag of tricks for flushing them out. The methods described can help testers provide a sensible answer to the question of what they really mean when they say they have finished testing a software system.
On the Modeling of Prismatic Joints in Flexible Multi-Body Systems ⁄

This paper focuses on the modeling of prismatic joints in flexible multi-body systems. In the classical formulation of prismatic joints for rigid bodies, kinematic constraints are enforced between the kinematic variables of the two bodies. These constraints express the conditions for relative translation of the two bodies along a body fixed axis, and imply the relative sliding of the two bodies which remain in constant contact with each other. However, these kinematic constraints no longer imply relative sliding with contact when one of the bodies is flexible. To remedy this situation, a sliding joint is proposed that involves kinematic constraints at the instantaneous point of contact between the sliding bodies. Various numerical examples are presented that demonstrate the dramatically different behavior of prismatic and sliding joints in the presence of elastic bodies.
Visual fixation of a target and suppression of optokinetic nystagmus: effects of varying target feedback

The ability to maintain foveal fixation of a target with either a stationary or moving background is often assumed to depend primarily on a difference (in velocity and/or position) between fovea and target. However, when subjects look at a target stabilized at the fovea presented against sinusoidal motion of an optokinetic stimulus field, optokinetic nystagmus (OKN) is suppressed. This suppression is not simply the absence of movement but instead most subjects show some amount of residual slow eye movements roughly counterphase to the field motion. We have varied the visual feedback of the target from 0 (stabilized) to -1 (stationary in space); as feedback increased, amplitude and phase lag of residual eye movements decreased systematically. The mechanism responsible for residual movements appears to operate for all feedback values (including the "real world" value of -1), which suggests a new view of the role played by retinal slip during fixation of a target and suppression of OKN.
Neural network models as evidence for different types of visual representations

Cook (1995) criticizes the work of Jacobs and Kosslyn (1994) on spatial relations, shape representations, and receptive fields in neural network models on the grounds that first-order correlations between input and output unit activities can explain the results. We reply briefly to Cook's arguments here (and in Kosslyn, Chabris, Marsolek, Jacobs & Koenig, 1995) and discuss how new simulations can confirm the importance of receptive field size as a crucial variable in the encoding of categorical and coordinate spatial relations and the corresponding shape representations; such simulations would testify to the computational distinction between the different types of representations.
A peer-education intervention to reduce injection risk behaviors for HIV and hepatitis C virus infection in young injection drug users

Objectives:To evaluate whether a behavioral intervention, which taught peer education skills, could reduce injection and sexual risk behaviors associated with primary HIV and hepatitis C virus infection (HCV) among young injection drug users (IDU).Design:We conducted a randomized controlled trial in
Design considerations of high voltage and high frequency three phase transformer for Solid State Transformer application

The three-phase Solid State Transformer (SST) is one of the key elements in the Future Renewable Electric Energy Delivery and Management (FREEDM) System. The SST consists of an input rectifier, Dual Active Bridge (DAB) bidirectional dc-dc converter and followed by an inverter for ac voltage output. The DAB converter is a bidirectional dc-dc converter using high frequency transformers to step up or down the voltages at high frequency for a reduction in size while maintaining high efficiency and reliability. The single phase high-frequency high-voltage transformer for two-level DAB has been reported by the authors [2]. In this paper, high frequency three-phase transformer for multi-level (3-level) and multi-phase (three-phase) DAB is designed for three-phase multilevel SST. There are two proposed topologies and for each topology the high voltage and high frequency transformer is designed at 3 kHz and 20 kHz. The proposed transformer designs for electromagnetic, thermal and mechanical analysis are validated with the simulation of Finite Element Analysis software.
Prestin Lateral Mobility and Self-Association in Outer Hair Cells

Prestin belongs to the SLC26 protein family, which regroups anion antiporters capable of transporting monovalent and divalent anions across biological membranes. Also referred to as SLC26A5, prestin is a motor protein essential for the electromotility of the outer hair-cells (OHC) and therefore the amplification of sound in the cochlea. The diffusion of prestin in the membrane has been previously studied through fluorescent recovery after photobleaching (FRAP) experiments, in HEK293 cells. We were able to determine that up to 50% of the prestin population was immotile. This suggest that intermolecular interactions between prestin, the membrane and the cytoskeleton are essential for prestin organization and function. We have created transgenic mouse lines co-expressing prestin-TFP and prestin-YFP. OHCs isolated from these mice have prestin-induced non linear capacitance (NLC) and electromotility comparable to wild-type mice.FRAP analysis on prestin-YFP indicated that in OHCs, the entire prestin population is immotile. This motility was partially recovered by inhibition of the actin filament polymerization. Fluorescent resonance energy transfer (FRET) coupled to fluorescence lifetime imaging microscopy (FLIM) allowed us to detect and monitor the prestin-prestin interactions at the nanometer scale. These FLIM-FRET experiments revealed a FRET efficiency of 25-35%.The FRAP experiments suggest a strong interaction of prestin with other membrane proteins or the cytoskeleton, and the high FRET efficiency will allow for prestin-prestin interactions to be monitored during alterations of the membrane composition and potential.
Cells and bubbles in sparged bioreactors

Ever since animal cells have been grown in-vitro, various techniques have been used to supply the cells with oxygen. The most simple and commonly used ‘large-scale’ technique to provide oxygen is through the introduction of gas bubbles. However, almost since the beginning of in-vitro cell culture, empirical observations have indicated that bubbles can be detrimental to the cells. This review will discuss the background of the problem, review the relevant research on the topic, attempt to provide a coherent summary of what we know from all of this research, and finally outline what still needs to be investigated. Specific topics to be covered include: experimental correlations of cell damage with bubbles, cell attachment to bubbles, the hydrodynamics of bubble rupture, bioreactor studies, visualization studies, and computer simulations and qualification of cell death as a result of bubble rupture.
A simple algebraic estimation procedure for innovation diffusion models of new product acceptance

Abstract A simple algebraic estimation procedure is developed to estimate the parameters of diffusion models of new product acceptance. The procedure required knowledge of the occurrence of the point of inflection (based on actual data, analogous products, or management judgments). It is conceptually easy to use and can be implemented by using a hand calculator. Since the procedure does not employ period-by-period time-series diffusion data, it is not expected to provide the best fit to the data as compared to the maximum likelihood and nonlinear least squares estimation procedures. However, the procedure can provide very reasonable estimates about the relative magnitudes of the parameter estimates. In that respect, the procedure can be used to generate good starting values for the maximum likelihood and nonlinear least squares estimation procedures. In the absence of data, using management judgments about the point of inflection, the procedure can be implemented in a decision-support system to develop conditional diffusion curves for a new product. Data from four diverse innovations are used to illustrate the procedure.
Fostering social presence in asynchronous online class discussions

The study examined the role of social presence in relation to students' perception of online asynchronous learning. Specifically, this study (a) examined the magnitude of the relationship between students' perceptions of social presence and their satisfaction with online class discussions, (b) investigated students' online behaviors which contributed to their own projected social presence, and (c) explored factors influencing students' perceptions of social presence, and the relationship between students' perceptions of others and their own projected presence in online course discussions. The study closes by exploring the implications for its findings for learning and teaching in online asynchronous learning environments.
President’s Page: Beijing 2009

The 15th biannual International Congress of the International Society of Cardiovascular Pharmacotherapy (ISCP) will be held on October 11–12, 2009 in Beijing in collaboration with the annual Great Wall International Congress of Cardiology. An exciting structured program has been finalized covering a wide range of contemporary issues in drug therapy for cardiovascular diseases. A feature of the program will be the Henry Neufeld Memorial Lecture given this year by Juan Carlos Kaski, Vice-President of ISCP. Poster sessions of selected submitted abstracts will provide an opportunity for wider participation. Young Investigator Awards will be bestowed on those abstracts from young researchers selected for excellence by a review committee. The program for the meeting is shown below.
From Interaction to Intersubjectivity: Facilitating online group discourse processes

This article examines the online discourse that took place in representative threads from two classes, seeking to document indicators that students did or did not engage in co‐construction of knowledge. Stahl's (2006) social theory of computer supported collaborative learning (CSCL) is used along with discourse analysis methods to examine these course dialogues. Findings show the class that had a peer‐like, consistent facilitative instructor and discussion anchored around questions and shared artifacts was more likely to engage in discussion leading to the negotiation of knowledge and understanding. This class relied on social acknowledgements, questions, and shared exploration of perspectives and theories throughout their discussion. These elements and strategies appear to be important components that make up for lower levels of tacit understanding in online environments, thus enabling learners to interact in social learning processes. The other class, which lacked a facilitative instructor, did not have...
On the Kinetics of Growth of Anodic Oxide Films

Two theories, the high field model (HFM), and variants thereof, and the point defect model (PDM), have been advanced to account for the properties of thin anodic passive films (barrier layers). The HFM states that, under potentiostatic conditions, the electric field strength in a passive film decreases as the film thickens, while the PDM proposes that the field strength remains constant but that the potential drop across the metal/film interface decreases as the film grows. These different hypotheses lead to different kinetic laws for film growth. In this work, diagnostic criteria have been derived to determine the electric field-thickness relationship and hence to identify the appropriate kinetic law. Experiments on the growth of anodic oxide films on zirconium, tungsten, and tantalum under potentiostatic conditions in phosphate buffer solution show that the PDM provides a better account of the experimental data than does the HFM.
A spectral model for evaluating the effect of wind evolution on wind turbine preview control

As wind turbines become larger and more flexible, the potential benefits of load mitigating control systems become more important to reduce fatigue and extend component life. In the last five years, there has been significant research activity exploring the effectiveness of preview control techniques that may be feasible using advanced wind measurement technologies like LIDAR (light detection and ranging). However, most control development tools use Taylor's frozen turbulence hypothesis. The end result is that preview measurements made up-stream from the rotor can be obtained with unrealistic accuracy, because the same wind velocities eventually arrive at the turbine. In this study, we extend the spectral methods commonly used to generate turbulent wind fields for controls simulation, but in a way that emulates wind evolution. This changes preview measurements made upwind from the rotor, in such a way that the differences- between the preview measurements and speeds arriving at the turbine- increase with distance from the rotor. We then evaluate the degradation in load mitigation performance of a controller that uses preview measurements obtained at various distances in front of the rotor.
Improving the firing of plates for steel-teeming ladle slide gates

The mathematical simulation of heat exchange during firing of refractories in tunnel kilns made it possible to develop technical measures to increase the productivity of the two-tunnel kilns by 33% and the annual production of the MKTsP-82 plates was 1500 tons. The improved firing conditions for plates in the tunnel kilns are characterized by an average rate of movement of the charge of 0.30 m/h and an interval between pushes of the cars of 20 min. During use of the improved firing method the operation of the basic production zones of the kiln was corrected. The increase obtained in tunnel kiln productivity and the reduction in specific fuel consumption was the result of this study of acceleration of the firing operation and economy in energy resources.
Stroboscopic earth inductor compass

The need for a sensitive, quick-acting, and reliable compass for small aircraft led to the development of this induction compass which utilizes the stroboscopic effect.
The life and death of Caterina Martinelli: new light on Monteverdi's ‘Arianna’

In the early spring of 1608 a calamity befell the Gonzaga court at Mantua with the sudden death of their young virtuoso singer, Caterina Martinelli. And the shock felt at her untimely demise was made all the worse by the realisation that the court's prestige and the standing of Duke Vincenzo himself were thereby threatened. More precisely, what was at risk were the elaborate plans that the Mantuans had made – plans in which Caterina Martinelli had figured very prominently – for an extraordinary series of musical-theatrical events to be held later in that spring to which the whole world (or at least all of it that mattered) had been invited.
The elderly: health status benefits and recovery of function one year after coronary artery bypass surgery

Abstract Objectives The purpose of this study was to describe the health status (symptoms, function, and quality of life) changes of elderly patients undergoing coronary artery bypass grafting (CABG) and compare these to younger patients. Background Despite increasing use of CABG in the elderly, few data exist about elderly patients' health status benefits from CABG. Methods A total of 690 consecutive patients (n = 156, >75 years of age; n = 534, ≤75 years of age) from a single center were administered the Seattle Angina Questionnaire (SAQ) at baseline and at one year. The first 224 patients were also given monthly questionnaires for six months after CABG. Results Although peri-operative mortality was similar (2.6% vs. 2.2%, p = NS), one-year mortality was greater in older patients (11.5% vs. 5.4%, p = 0.008). Among survivors, similar health status benefits were observed one year after surgery (SAQ change scores for Physical Function 21.5 ± 27.0 vs. 19.7 ± 27.0, p = 0.67; Angina Frequency 30.1 ± 25.7 vs. 24.6 ± 25.6, p = 0.07; and Quality of Life 37.7 ± 21.8 vs. 33.6 ± 25.2, p = 0.16). In 224 patients assessed monthly, elderly patients' physical function scores were significantly lower than the younger group until one year. The age-time interaction term was significant (p = 0.003), confirming a slower recovery of physical function. In contrast, angina relief and quality of life improvement did not differ by age. Conclusions Despite a slower rate of physical recovery, older patients derived similar health status benefits from CABG compared with younger patients. These data should assist physicians in counseling elderly patients and suggest that age alone should not be a deterrent for recommending bypass surgery.