cssi/SciSciGPT-SciSciNet huggingface dataset:
Prevention of Bone Marrow Cell Apoptosis and Regulation of Hematopoiesis by Type I IFNs during Systemic Responses to Pneumocystis Lung Infection

We recently demonstrated that lack of type I IFN signaling (IFNAR knockout) in lymphocyte-deficient mice (IFrag(-/-)) results in bone marrow (BM) failure after Pneumocystis lung infection, whereas lymphocyte-deficient mice with intact IFNAR (RAG(-/-)) had normal hematopoiesis. In the current work, we performed studies to define further the mechanisms involved in the induction of BM failure in this system. BM chimera experiments revealed that IFNAR expression was required on BM-derived but not stroma-derived cells to prevent BM failure. Signals elicited after day 7 postinfection appeared critical in determining BM cell fate. We observed caspase-8- and caspase-9-mediated apoptotic cell death, beginning with neutrophils. Death of myeloid precursors was associated with secondary oxidative stress, and decreasing colony-forming activity in BM cell cultures. Treatment with N-acetylcysteine could slow the progression of, but not prevent, BM failure. Type I IFN signaling has previously been shown to expand the neutrophil life span and regulate the expression of some antiapoptotic factors. Quantitative RT-PCR demonstrated reduced mRNA abundance for the antiapoptotic factors BCL-2, IAP2, MCL-1, and others in BM cells from IFrag(-/-) compared with that in BM cells from RAG(-/-) mice at day 7. mRNA and protein for the proapoptotic cytokine TNF-α was increased, whereas mRNA for the growth factors G-CSF and GM-CSF was reduced. In vivo anti-TNF-α treatment improved precursor cell survival and activity in culture. Thus, we propose that lack of type I IFN signaling results in decreased resistance to inflammation-induced proapoptotic stressors and impaired replenishment by precursors after systemic responses to Pneumocystis lung infection. Our finding may have implications in understanding mechanisms underlying regenerative BM depression/failure during complex immune deficiencies such as AIDS.
Asymptotic Stabilization of Euler-Poincaré Mechanical Systems

Stabilization of mechanical control systems by the method of controlled Lagrangians and matching is used to analyze asymptotic stabilization of systems whose underlying dynamics are governed by the Euler-Poincar´e equations. In particular, we analyze asymptotic stabilization of a satellite.
Accelerator Mass Spectrometry of Heavy Elements: $^{36}$Cl to $^{205}$Pb

Measurements are discussed in which the technique of accelerator mass spectrometry was applied to problems involving heavy radioisotopes. These measurements, which depend on the ion energies that can be reached with the new heavy-ion accelerator facilities, were performed at the Argonne tandem linac accelerator system (atlas) and at the unilac accelerator at GSI. The topics include a discussion of measurements of long nuclear lifetimes, of radioisotope detection of interest to solar neutrino experiments, and of a determination of the 41 Ca concentration in natural samples of terrestrial origin by m aking use of isotopic pre-enrichm ent in an isotope separator. A long-known m ethod of isobar separation, employing a gas-filled m agnetic field region, has been revived for some of these m easurem ents and its characteristics and advantages are briefly reviewed.
Occupational sex-typing by kindergarten and fourth-grade children

Summary.-Sex-typing of occupations and its antecedent elements have been investigated using different methods across a variety of age groups. Exp. 1 utilized a memory test as its principal criterion, along with a jobpreference question to investigate sex-typing in fourth-grade children. On the memory test the mean numbers of sex-qping errors were significantly different; the subjects presenting traditional sex-typed pairings committed far fewer sextyping errors. The job-preference question also disclosed sex-typed beliefs pertaining to occupational aspirations. The method in Exp. 2 required 66 kindergarten children to supply names to stick figures performing traditions: male and female occupations in each of 10 picture cards. A significant number of sex-typed responses were given. Girls were more sex-typed than boys, traditional male occupations were more sex-typed than traditional female occupations, and boys were less sex-typed when their mothers were employed. It is evident that children have many preconceived ideas about the future occupations they one day may hold. A child's perception of the work world and the possibilities of future employment may be influenced by a diverse set of determinants. One of the agents involved is sex-typing: a child's tendency to associate certain occupations with the domain of men or women. Researchers have found that sex-typing of occupations occurs as early as kindergarten and first grade (Gregg & Dobson, 1980; Scheresky, 1977; Teglasi, 1981). EXPERIMENT 1 Exp. 1 utilized the usual job-preference question to investigate sex-typing, but the principal criterion for its measurement was the number of sex-typing errors given by each subject on a memory test. Subjects were shown 12 flashcards, each with a common proper name and occupation printed on it. Half of the subjects were presented cards with traditional sex-typed occupations and names, while the other half were presented nontraditional sex-typed pairings. The hypothesis was that children presented the nontraditional pairings would make more sex-typing errors when asked to recall them correctly. A sex-typed error was defined as incorrectly recalling a traditional sex-typed pairing (e.g., Lawyer-Dan) and matching it on the posttest as a nontraditional pairing (e.g., Nurse-Dan) or incorrectly recalling a nontraditional sex-typed pairing (e.g., Carpenter-Jan) and matching it on the posttest as a traditional
Personalization of Helping Relationships: Resident Service Coordinators' Work with Elderly Residents

As part of a larger study, in-depth interviews were conducted with 26 Resident Services Coordinators (RSCs) working in elderly housing to explore their experiences working with residents. Qualitative analysis revealed a major theme: RSCs view themselves as critical sources of support in residents' lives. Additionally, two subthemes reveal the affective nature of the relationships that RSCs form with residents: (a) Some RSCs working with elders report a very strong sense of obligation to familyless or isolated elders; and (b) in some instances, they describe their relationships with residents using family-like terms. Frail residents' limited access to support appears to strengthen the affective bond that some RSCs form with residents. The findings have implications for understanding how RSCs view their role and the emotional rewards and costs that RSCs experience in their role.
Approaches for assessing the efficacy of occupational health and safety standards

The regulation of hazards is one of the most dramatic forms of intervention in occupational safety and health (OSH). Despite their high degree of potential social and economic impact, relatively little research has been conducted to specifically evaluate the effectiveness of OSH standards with regard to preventing occupational diseases and injuries. This paper reviews the basic scientific approaches that may be used to evaluate the efficacy of OSH standards. These approaches encompass the following research areas: (1) exposure surveillance, (2) disease surveillance, and (3) prospective studies following the introduction of the standard. Research on asbestos and asbestosis, respirable crystalline silica (quartz) and silicosis, and respirable coal mine dust and coal workers' pneumoconiosis (CWP) are used to illustrate these approaches and the type of information that is currently available. The examples (quartz coal dust, asbestos) reveal substantial limitations in the types of information currently available for evaluating the efficacy of these OSH standards. Ideally, plans for evaluating the efficacy of OSH standards should be developed for existing and future standards. These plans should include programs for the surveillance of exposures and adverse health effects and, when possible, for prospective studies designed to evaluate how the risk of disease (or injury) is modified by the introduction of the standard. (This article is a US Government work and, as such, is in the public domain in the United States of America.) © 1996 Wiley-Liss, Inc.
Soy but not bisphenol A (BPA) induces hallmarks of polycystic ovary syndrome (PCOS) and related metabolic co-morbidities in rats

Polycystic ovarian syndrome (PCOS) is the most common female endocrine disorder with a prevalence as high as 8-15% depending on ethnicity and the diagnostic criteria employed. The basic pathophysiology and mode of inheritance remain unclear, but environmental factors such as diet, stress and chemical exposures are thought to be contributory. Developmental exposure to endocrine disrupting compounds (EDCs) have been hypothesized to exacerbate risk, in part because PCOS hallmarks and associated metabolic co-morbidities can be reliably induced in animal models by perinatal androgen exposure. Here we show that lifetime exposure to a soy diet, containing endocrine active phytoestrogens, but not developmental exposure (gestational day 6-lactational day 40) to the endocrine disrupting monomer bisphenol A (BPA), can induce key features of PCOS in the rat; results which support the hypothesis that hormonally active diets may contribute to risk when consumed throughout gestation and post-natal life.
Target personality and workplace victimization: A prospective analysis

Abstract Workplace victimization has recently emerged as an important topic in occupational health psychology. One of the major limitations of this research is that it generally employs cross-sectional designs. The current study, however, used a 13-month two-wave prospective design to examine the relationship between target personality and workplace interpersonal conflict in a sample of 166 non-faculty employees at a Midwestern university in the United States. Results suggested that victims' positive affectivity, negative affectivity, and core self-evaluations were associated with interpersonal conflict. Furthermore, employee personality was related to subsequent interpersonal conflict from supervisors even after initial levels of interpersonal conflict were controlled. Analyses further suggested that target negative affectivity might be an especially strong predictor of interpersonal conflict. Consistent with past theorizing, we found evidence that initial interpersonal conflict with co-workers can resul...
Dynamic sleep time control in wireless sensor networks

Idle listening is a major source of energy waste in wireless sensor networks. It can be reduced through Low-Power Listening (LPL) techniques in which a node is allowed to sleep for a significant amount of time. In contrast to conventional fixed sleep time policies, we introduce a novel dynamic sleep time control approach that further reduces control packet energy waste by utilizing known data traffic statistics. We propose two distinct approaches to dynamically compute the sleep time, depending on the objectives and constraints of the network. The first approach provides a dynamic sleep time policy that guarantees a specified average delay at the sender node resulting from packets waiting for the end of a sleep interval at the receiver. The second approach determines the optimal policy that minimizes total energy consumed. In the case where data traffic statistics are unknown, we propose an adaptive learning algorithm to estimate them online and develop corresponding sleep time computation algorithms. Simulation results are included to illustrate the use of dynamic sleep time control and to demonstrate how it dominates fixed sleep time methods. An implementation of our approach on a commercial sensor node supports the computational feasibility of the proposed approach.
The effect of unionization on labor productivity: Some additional evidence

Following Brown and Medoff (1978), a number of studies have investigated the effect of unionization on labor productivity using a log-linear, Cobb-Douglas model of technology. To derive this model, a first-order Taylor-series approximation to the intrinsically nonlinear unionization variable is made; the resulting linear equation is estimated with generalized least-squares (GLS) techniques. We demonstrate that this approximation introduces a bias that necessarily results in an overstatement of the absolute value of the exact union productivity effect. We illustrate the magnitude of this bias by comparing GLS estimates of the linear Brown-Medoff model with GLS estimates of the exact, nonlinear relationship, using aggregate time-series data from the private domestic sector of the U.S. economy.
Imprint of gravitational waves in models dominated by a dynamical cosmic scalar field

An alternative to the standard cold dark matter model has been recently proposed in which a significant fraction of the energy density of the universe is due to a dynamical scalar field $(Q)$ whose effective equation of state differs from that of matter, radiation or cosmological constant $(\ensuremath{\Lambda}).$ In this paper, we determine how the $Q$ component modifies the primordial inflation gravitational wave (tensor metric) contribution to the cosmic microwave background anisotropy and, thereby, one of the key tests of inflation.
Suppression subtractive hybridisation: application in the discovery of novel pharmacological targets.

Suppression subtractive hybridisation (SSH) is a recently developed technology designed for identifying differentially expressed genes. Total cellular RNA isolated from two sources of tissue (such as diseased versus normal) is reverse-transcribed to generate cDNA and subtracted. One critical feature of this technique is the suppression polymerase chain reaction (PCR) in combination with subtraction. To optimise the subtraction the cDNA is digested with a restriction enzyme to generate small DNA fragments (~500 nucleotides in length). Specially designed DNA adapters are ligated onto one of the cDNA pools (usually the diseased one), which is followed by two rounds of hybridisation and PCR. Since this method is PCR-based, it is sensitive and efficient to identify genes of interest. The discovery of disease-related genes is an important step for the identification of novel therapeutic targets.
Management of nonsinonasal neuroendocrine carcinomas of the head and neck

BACKGROUND Nonsinonasal neuroendocrine carcinomas (NSNEC) of the head and neck are rare and pose a diagnostic and management challenge. The authors undertook a retrospective study to gain insights into the spectrum of clinicopathologic characteristics, patterns of failure, and optimal management of patients with this disease. METHODS The authors treated 23 adults with pathologically proven, nonmetastatic, primary NSNEC from 1984 to 2001. The majority (13 patients) had laryngeal origin with the following American Joint Committee on Cancer stage distribution: Stage I disease in 1 patient, Stage II disease in 2 patients, Stage III disease in 6 patients, and Stage IV disease in 14 patients. Nine patients underwent definitive surgery with or without postoperative radiation, and 14 patients received definitive radiotherapy. The median definitive radiation dose was 66 grays (Gy) (range, 44–72 Gy) using conventional fractionation. Fourteen patients received chemotherapy, with two to four cycles of induction platinum plus etoposide used most commonly. RESULTS The median follow-up time for surviving patients was 40 months (range, 15–89 months). The actuarial 2-year and 5-year overall survival (OS) rates were 53% and 33%, respectively; and the disease-free survival (DFS) rates were 41% and 25%, respectively. Both the 2-year OS rate (68% vs. 30%; P = 0.002) and the 2-year DFS rate (55% vs. 17%; P = 0.004) were improved with chemotherapy compared with local therapy alone. Seventy-five percent of patients with measurable disease had complete clinical responses to induction chemotherapy. There was 100% complete clinical response of tumor after radiotherapy. The actuarial 2-year local failure rate was 23%. Chemotherapy did not reduce local failure (P = 0.91). There was no regional failure. The 2-year and 5-year distant metastasis rates were 54% and 71%, respectively. The 2-year rates of metastases without and with chemotherapy were 79% and 39%, respectively (P = 0.006). The 2-year and 5-year rates of intracranial metastases were 25% and 44%, respectively, and the 2-year and 5-year rates of isolated brain metastases were 21% and 41%, respectively. CONCLUSIONS Based on these results, the authors' treatment strategy for patients with NSNEC is sequential chemotherapy and radiation. They recommend full-dose radiotherapy alone for patients with NSNEC who achieve a complete clinical response to induction chemotherapy. Newer chemotherapeutic regimens or additional adjuvant chemotherapy should be investigated for patients with NSNEC given the high rate of distant failure. Due to the very high rate of brain metastases among patients in the current study, the authors now consider incorporating prophylactic cranial irradiation into primary radiotherapy for individual patients who have complete clinical responses to induction chemotherapy. Cancer 2003. © 2003 American Cancer Society.
Reductant-Independent ATP Hydrolysis Catalyzed by Homologous Nitrogenase Proteins fromAzotobacter vinelandiiand Heterologous Crosses withClostridium pasteuranium

Abstract Reductant-independent ATPase activity was initiated and studied forAzotobacter vinelandiiandClostridium pasteuraniumnitrogenase proteins (Av1, Cp1 and Av2, Cp2, 1 designating the iron molybdenum protein and 2 the iron protein) and their heterologous crosses by two methods: (1) allowing dithionite to be depleted from a normal assay in the presence of substrate levels of MgATP and (2) using reduced but reductant-free nitrogenase proteins in the presence of substrate levels of MgATP. In both cases, at a 1:1 protein ratio, MgATP is converted initially to MgADP with a specific activity of 400–500 nmol MgATP hydrolyzed/min·mg Av1, but in slower steps the MgADP is converted to AMP and, after 12 h, AMP is ultimately converted to adenosine. This reactivity requires the presence of both proteins, increases with increasing Av2/Av1 ratio, and is not a result of unique redox states of either protein. For Av1–Av2, ATP hydrolysis in the absence of Mg2+occurred at nearly the same rate as reductant-dependent MgATP hydrolysis. Reductant-independent ATPase activity also occurred for the Av1–Cp2 and Cp1–Av2 heterologous crosses and was 2-fold and 18-fold slower than the Av1–Av2 or Cp1–Cp2 combinations. In both cases further hydrolysis of MgADP to AMP and AMP to adenosine occurred. A unique nucleotide hydrolysis system is apparently operating in the complex formed between the two nitrogenase proteins in the absence of reductant. The relationship between the reductant-independent and reductant-dependent activities of nitrogenase catalysis is explored.
A semistability-based design framework for optimal consensus seeking of multiagent systems in a noisy environment

This paper addresses semistable stochastic Linear-Quadratic Consensus (LQC) problems motivated by the recently developed Optimal Semistable Control (OSC) and semistable H 2 control problems. OSC deals with linear-quadratic optimal semistabilization. In the framework of OSC, the closed-loop system is not asymptotically stable, but semistable. Semistability is the property that every trajectory of the closed-loop system converges to a Lyapunov stable equilibrium point determined by the system initial conditions. Hence, the limiting state of the closed-loop system is not a fixed point a priori, but a continuum of equilibria. In such a sense, OSC can be viewed as an optimal regulation problem with nondeterministic, nonzero set-points. In this paper, we consider stochastic OSC for optimal consensus seeking under white noise and random distribution of initial conditions. We show that the distinct feature of the proposed semistable stochastic LQC problem is the possibility of nonuniqueness of the solutions and hence, cannot be treated by using the methods developed for the classical LQR control theory. We develop a new framework for semistable stochastic LQC and suggest an alternative constrained optimization method to solve it. To this end, necessary and sufficient conditions for semistability and optimal consensus seeking under white noise and random distribution of initial conditions are derived in the paper.
Spreadsheet-Based Design and Analysis of Mechanisms

A spreadsheet based mechanism analysis and animation system is presented in this article. The system is developed in Excel using Ch, an embeddable C/C++ interpreter, and Ch Mechanism Toolkit. It allows users to develop and solve complicated planar mechanism problems conveniently using an easy to use Excel spreadsheets as the front end. Users can input the required data to define a mechanism in an Excel spreadsheet and execute script files associated with the work cells. The spreadsheet based system can be used for kinematic and dynamic analysis, graphical plotting, and animation for four-bar, crank-slider, fivebar, and sixbar linkages. Examples are provided to illustrate its ease of use. The source code and demos are available for downloading from the internet.Copyright © 2006 by ASME
Radiation Protection Design Considerations for Man in Geosynchronous Orbits

A description is presented of preliminary studies which have been carried out to identify design requirements and mission constraints imposed by the geosynchronous radiation environment. The radiation species of dominant impact are the trapped electrons and solar flare particles. The criterion used in the conducted shielding design analysis has been to limit the skin dose to 100 rems for 3 months. The analysis included the optimization of an electron/bremsstrahlung shield for residence within the vehicle, the minimization of the dose received in extravehicular activity, and the calculation of special shield requirements for solar flares. An investigation was conducted of the potential benefits accruing from a three-layered composite shield with part of the aluminum layer replaced with a lower atomic number material. The materials considered were polyethylene, carbon, beryllium, and lithium hydride.
Alpha M —: An improved computer program for determining radioisotopes by least-squares resolution of the gamma-ray spectra

Abstract Alpha M is an improved version of program Alpha - more versatile, more accurate, and also reduces the cost per determination. Fewer counts per channel are required, variations of the background are compensated for, computation time is reduced, results of consecutive spectra can be added, and initial conditions can be changed. A further improvement over Alpha is that the new program includes instructions for use with FORTRAN II, 62, 63, and IV languages and several digital computers - CDC-1604, -3600, IBM-7094/0, and -360. An instruction manual and Alpha M (with two sample problems) are available from the author.
Human erythrocyte phosphoglycerides. II. Diet and lecithin structure

Lecithins (separated on basic silicic acid columns) were obtained from humans fed three different diets: eitherad-libitum or diets containing 40% of calories from linoleic acid (as corn oil) or from oleic acid (as triolein). Four lecithin subfractions were studied from each dietary group. Lecithin fractions eluting earliest (and apparently the least polar) contained the highest molar ratios of unsaturated fatty acids and the highest proportion of C-20 to C-22 polyunsaturated fatty acids. A slight increase in proportions of diunsaturated molecules occurred in corn oil and triolein groups. However, over 90% of lecithins of each dietary group were maintained as themonosaturated - monounsaturated type. Therefore, in contrast to human adipose tissue triglycerides, the saturated/unsaturated fatty acid ratio of lecithins of the erythrocyte membrane is largely unaffected by immense increases in dietary unsaturated fatty acid. Major shifts of oleic and linoleic acid occurred but proportions were unaltered of longer chain length (>C-18) polyunsaturated fatty acids. The relevance of these findings to membrane structure and function and to glycerophosphatide biosynthesis is discussed.
Laparoscopic radiofrequency ablation of hepatic tumors: prospective clinical evaluation of ablation size comparing two treatment algorithms.

Background: Radiofrequency ablation (RFA) is gaining increased acceptance for the local control of liver tumors. Essential for achieving local tumor control are reproducible volumes of ablation that encompass the tumor and a margin of normal liver parenchyma. The technical algorithm for performing ablations was arrived at in an animal model using normal liver. Limited amounts of data exist as to whether this translates to the human tumor model. Methods: We analyzed 531 ablated lesions in 154 patients undergoing laparoscopic RFA using RITA Medical Systems Starburst XL catheter deployed to a final diameter of 2–5 cm. The first 54 patients (algorithm 1) were treated with a larger initial deployment to 3 cm and incremental advancement of the catheter to the final diameter with a 20-min ablation time for a 5-cm lesion. The subsequent 100 patients (algorithm 2) were treated with a smaller initial deployment of 2 cm, incremental advancement to the final diameter, and 14-min total ablation time for a 5-cm lesion. Lesion size was measured on 1 week postablation CT scans. Analysis was performed using the two-tailed t-test. Results: Ablation zones tended to be larger with the second method. On 1 week postablation CT scans, mean ± SEM lesion sizes created using the first and second algorithms were 3.7 ± 0.1 cm vs 4.0 ± 0.1 cm at 3 cm deployment (p 0.05), respectively. The mean ± SEM total ablation times for the first and second algorithms were 7.9 ± 0.3 min vs 7.0 ± 0.2 min at 3 cm deployment (p < 0.05); 13.3 ± 0.3 min vs 11.1 ± 0.02 min at 4 cm deployment (p < 0.05); and 27.8 ± 1.2 min vs 21.4 ± 1.2 min at 5 cm deployment (p < 0.05), respectively. The small SEM values indicate little variation in lesion size. Conclusions: These results show that both algorithms create dependable and reproducible zones of ablation, essential for reliable tumor destruction. Algorithm 2 demonstrates that creating an initial small core of ablation with rapid coagulation of the center of the lesion allows for equivalent, if not larger, final volumes to be performed in less time.
Morbid Obesity in the Medical ICU

Study objective To describe the clinical course, complications, and prognostic factors of morbidly obese patients admitted to the ICU compared to a control group of nonobese patients. Design A retrospective study. Setting Two university-affiliated hospitals. Methods We reviewed the medical records of 117 morbidly obese patients (body mass index ≥ 40 kg/m2) admitted to the medical ICU between January 1994 and June 2000. Data collected included demographic information, comorbid condition, APACHE (acute physiology and chronic health evaluation) II score, invasive procedures, organ failure, and in-hospital mortality. Results Obstructive airway disease, pneumonia, and sepsis were the main reasons for admission to the ICU in the morbidly obese group. Sixty-one percent of the morbidly obese patients and 46% of the nonobese group required mechanical ventilation (p = 0.02). The mean lengths of mechanical ventilation and ICU stay were significantly longer for the morbidly obese group (7.7 ± 9.6 days and 9.3 ± 10.5 days vs 4.6 ± 7.1 days and 5.8 ± 8.2 days, respectively; p 48 h (OR, 2.3; 95% CI, 1.2 to 7.8), and depressed left ventricular ejection fraction Conclusion We conclude that critically ill morbidly obese patients are at increased risk of morbidity and mortality compared to the nonobese patients.
A freeze fracture and thin section study of intestinal cell membranes and intercellular junctions of a nematode, Ascaris.

Abstract The microvillar and lumenal plasma membrane P-face of Ascaris intestinal cells is shown to be covered by relatively large (13 nm) particles at a fairly high density (1000/μm 2 ), while the E-face has virtually none. The P-face of the lateral cell membranes, those separating the cells, have fewer and smaller (8 nm) particles. The intestinal cells are also shown to be connected by an apical complex of smooth septate and tricellular junctions similar to those found between some insect midgut cells. A periodic layer of tannic acid staining material is found on the cytoplasmic sides of the smooth septate junction, and when the intercellular space is filled with lanthanum, smoothly curved, 10 nm wide septal walls can be seen. Below the belt of septate junctions are a large number of gap junctions. These have closely packed arrays of particles on the P-face with some particle aggregates adhering to the closely packed pit arrays on the E-face.
Tachistoscopic presentation and millisecond timing on the IBM PC/XT/AT and PS/2: A Turbo Pascal unit to provide general-purpose routines for CGA, Hercules, EGA, and VGA monitors

A review of the literature on adopting microcomputers for use in tachistoscopic research paradigms illustrates the need for a comprehensive package to effectively deal with the wide variety of video displays and microcomputers used in experimental settings. In addition, because of the large number of possible configurations created when video displays and computer systems are combined, there is a need to be able to efficiently drive any such combination without rewriting program code. A Turbo Pascal unit is presented to provide standard tachistoseopic routines compatible with monochrome, CGA, Hercules, EGA, and VGA video technology. Procedures that synchronize both text and graphics mode stimuli with the vertical retrace pulse are given, as are routines to provide access to a timer with better than millisecond precision. Pascal code is described that will run on the IBM PC, XT, AT, or PS/2, as well as on any compatible machine. The versatility of the unit allows the experimenter to use generic video and timer commands that will automatically adapt at run time to the system that is being used, without further experimenter intervention.
Are we drifting toward a segregated workplace

The article reports on a study by Joel Lefkowitz concerning de facto segregation and job placement at a privately-owned commercial bank. A pattern of congruent racial assignments--where white and black employees were assigned to supervisors who were of their race--was found while examining the validity of employment testing. However, the bank management had no intention to discriminate. Lefkowitz concluded that the de facto segregation was the result of a likes-attracting-likes interaction, which he called “ethnic drift.”
Fucosyl gangliosides of PC12 pheochromocytoma cells

Abstract Three monosialogangliosides are highly labeled when PC12 pheochromocytoma cells are cultured in the presence of L-[ 3 H] fucose, and two additional monosialogangliosides are labeled to a lesser extent. In contrast, neither of the two disialogangliosides of PC12 cells contains fucose residues. Removal of sialic acid and fucose by formic acid hydrolysis demonstrated the presence of 3 major ‘core’ structures in the monosialogangliosides, and a single asialo derivative of the disialogangliosides which has the same chromatographic mobility as one of the monosialoganglioside hydrolysis products. None of the major formic acid hydrolysis products of the PC12 cell gangliosides corresponds to asialo-GM 1 , supporting our previous conclusion that PC12 cells do not contain significant amounts of brain-type gangliosides.
The interaction of dichoptically presented spatial gratings

Abstract Binocular interaction was investigated using a psychophysical detection paradigm. A grating with a fixed spatial frequency was presented to one eye and a grating which was varied in spatial frequency and/or phase was presented to the other eye. The results suggest the operation of three distinct processes: one, in which the gratings are matched on a point for point basis; one in which the respective gratings activate independent phase selective channels; and one in which the respective gratings activate independent spatial frequency selective channels.
Effects of tillage and application rate on atrazine transport to subsurface drainage: Evaluation of RZWQM using a six-year field study

a b s t r a c t Well tested agricultural system models can improve our understanding of the water quality effects of management practices under different conditions. The Root Zone Water Quality Model (RZWQM) has been tested under a variety of conditions. However, the current model's ability to simulate pesticide trans- port to subsurface drain flow over a long term period under different tillage systems and application rates is not clear. Therefore, we calibrated and tested RZWQM using six years of data from Nashua, Iowa. In this experiment, atrazine was spring applied at 2.8 (1990-1992) and 0.6 kg/ha/yr (1993-1995) to two 0.4 ha plots with different tillage (till and no-till). The observed and simulated average annual flow weighted atrazine concentrations (FWAC) in subsurface drain flow from the no-till plot were 3.7 and 3.2 g/L, respectively for the period with high atrazine application rates, and 0.8 and 0.9 g/L, respectively for the period with low application rates. The 1990-1992 observed average annual FWAC difference between the no-till and tilled plot was 2.4 g/L while the simulated difference was 2.1 g/L. These observed and simulated differences for 1993-1995 were 0.1 and 0.1 g/L, respectively. The Nash-Sutcliffe model per- formance statistic (EF) for cumulative atrazine flux to subsurface drain flow was 0.93 for the no-till plot testing years (1993-1995), which is comparable to other recent model tests. The value of EF is 1.0 when simulated data perfectly match observed data. The order of selected parameter sensitivity for RZWQM simulated FWAC was atrazine partition coefficient > number of macropores > atrazine half life in soil > soil hydraulic conductivity. Simulations from 1990 to 1995 with four different atrazine application rates applied at a constant rate throughout the simulation period showed concentrations in drain flow for the no-till plot to be twice those of the tilled plot. The differences were more pronounced in the early simu- lation period (1990-1992), partly because of the characteristics of macropore flow during large storms. The results suggest that RZWQM is a promising tool to study pesticide transport to subsurface drain flow under different tillage systems and application rates over several years, the concentrations of atrazine in drain flow can be higher with no-till than tilled soil over a range of atrazine application rates, and atrazine concentrations in drain flow are sensitive to the macropore flow characteristics under different tillage systems and rainfall timing and intensity. Published by Elsevier B.V.
Application of pressure-cycle purge (PCP) in dry-down of ultra-high-purity gas distribution systems

Abstract The existence of trace amounts of moisture in process gases could adversely affect the fabrication of semiconductor devices. One important and practical challenge in transporting ultra-high-purity (UHP) gases from the point-of-storage (POS) to the point-of-use (POU) is the susceptibility of the gas distribution systems to molecular contaminants, especially moisture. In modern micro/nanoelectronic manufacturing plants, the moisture content at the POU has to satisfy very stringent specifications. Once a distribution system is contaminated, a significant amount of purge time is required to recover the system background due to the strong interactions between moisture molecules and the inner surfaces of the components in a gas distribution system. Because of the very high cost of UHP gases and factory downtime, it is critical for high-volume semiconductor manufacturers to reduce purge gas usage as well as purge time during the dry-down process. In the present work, a combination of experimental investigation and process simulations is used to compare the traditional steady-state purge (SSP), which typically is operated at constant pressure and flow rate, with the pressure-cycle purge (PCP) process in which the pressure and flow rate are cycled at a controlled frequency and interval. The results show that under certain conditions the new PCP process has significant advantages over the SSP process; for example, it reduces the purge time and gas usage when the gas purity at POU is the principal concern. This conclusion was confirmed by the experimental investigation on lab-scale gas distribution test beds as well as by the simulation of industrial scale systems. The process model developed and used in this work couples gas phase transport processes with surface adsorption/desorption and the purge schedule introduced by pressure variation in the system. This model is then validated using experimental results under various operating conditions. The process simulator is a useful tool for industrial applications in parametric studies and purge process optimization. The effect of key operational parameters, such as start time of PCP process as well as choice of PCP patterns in the PCP process, are presented.
Photosynthetic responses of three species to acute exposures of nitrate- and sulphate-containing aerosols

Abstract Photosynthetic characteristics of leaves of bur oak (Quercus macrocarpa), soybean (Glycine max), and maize (Zea mays) were measured before and after acute (2–5h) exposures to dry, particulate KNO3, NH4NO3, or (NH4)2SO4. Aerosols were 0.25 μm in diameter, and concentrations were higher than the range reported for air sampled in polluted regions. Although CO2 uptake rates decreased following exposure to KNO3 in bur oak and to (NH4)2SO4 in maize, and increased following exposure to NH4NO3 in soybean, observed changes were small and were not observed in all cases. Therefore, the results of this study indicate that acute exposure to high concentrations of these dry, nitrate- and sulphate-containing aerosols have only slight effects on photosynthesis in these species.
Magnetic Field Strength Fluctuations and the q-Triplet in the Heliosheath: Voyager 2 Observations from 91.0 to 94.2 AU at Latitude 30° s

Voyager 2 (V2) was in the heliosheath during 2010, at (91.0-94.2) AU from the Sun and at the latitudes (28. Degree-Sign 8-29. Degree-Sign 3 S) AU, observing solar wind that left the Sun during 2009, when solar activity was very low. There was no feature in B(t) associated with the changes in the plasma parameters observed near 2010.4. The CR-B relation was satisfied. The fluctuations of daily averages of B showed (1) a Gaussian distribution of B, (2) a q-Gaussian of the daily increments of B with q = 1.6, (3) a power-law correlation of B on scales from 1 to 16 days, (4) multifractal structure of B on scales from 1 to 8 days, and (5) a 1/f spectrum of B on scales from 1 to 100 days. The amplitude of the compressive microscale fluctuations of B during several hours on each day is described by the standard deviation (SD) of the 48 s averages of B during the day. Items 2, 3, and 4 determine a 'q-triplet' in the heliosheath. Large-scale fluctuations of SD show (1) a lognormal distribution of SD; (2) an average value of SD = 0.19, 20% of the average B; (3) a q-Gaussian distributionmore » of the increments of SD with q = 1.4; (4) a power-law correlation on scales from 1 to 16 days; and (5) a 1/f spectrum on scales from 1 to 100 days. The heliosheath was in a quasi-stationary, metastable equilibrium state with well-defined structure over a wide range of scales near V2 during 2010.« less
Dental Education's Role in Improving Children's Oral Health and Access to Care

In 2000, Oral Health in America: A Report of the Surgeon General identified disparities in oral health and access to care for vulnerable populations, including children. The report identified a declining dental school applicant pool, shortages of dental school faculties, and an overcrowded curriculum as dental education factors affecting disparities. Dental school applications are up, but the dentist/population ratio is projected to decline, and the shortage of dental faculty has worsened—limiting dental students' experiences with children. Current Commission on Dental Accreditation (CODA) standards do not include essential curriculum required to care for children. We recommend that CODA revisions to predoctoral and postdoctoral programs include care of infants, characteristics of children that distinguish them from adults, mandatory service learning experiences, emphasis upon social responsibility for all dentists, and use of objective standardized clinical examinations (OSCEs). Additionally, we recommend prioritization of limited pediatric dental resources to young children with disease and older children with complex dental requirements or special health care needs. Critical dental education goals for children should be developed through a special American Dental Education Association task force. Only the dental education community can assure that the dental workforce is better trained to care for children.
Pediatric solid malignancies: neuroblastoma and Wilms' tumor.

Neuroblastoma and Wilms' tumor are two of the most common extracranial solid malignancies in infants and children. Despite intense basic science and clinical investigations, the overall survival for patients with advanced-stage neuroblastoma remains dismal. In Wilms' tumor, recent advances in the preoperative imaging have changed the operative approach to the routine contralateral kidney exploration. This article reviews the pathology, clinical presentation, diagnosis and treatment of neuroblastoma and Wilms' tumor.
Assessment of EmboGel--a selectively dissolvable radiopaque hydrogel for embolic applications.

Abstract Purpose To evaluate the embolic properties of an alginate-based embolic biomaterial (EmboGel) and its solvent (EmboClear) in treatment of aneurysms. Materials and Methods EmboGel is a mixture of iohexol and alginate that polymerizes into a hydrocoil when delivered through a coaxial catheter with a distal mixing tip, exposing alginate to a calcium chloride solution. In contrast to previously reported embolic agents, EmboGel can be selectively dissolved by EmboClear, a mixture of the enzyme alginate lyase and ethylenediaminetetraacetic acid (EDTA). The embolic and contrast properties of EmboGel were assessed in in vitro models of saccular aneurysm and an aortic aneurysm endoleak. The dissolvability of EmboGel with EmboClear was assessed further after endovascular delivery in the New Zealand white rabbit in the native aortoiliofemoral territory, a created saccular aneurysm, and the native carotid arteries. Results EmboGel effectively filled aneurysm cavities in the case of stent excluded saccular and fusiform aneurysms. EmboGel was readily dissolved by EmboClear in vitro and after in vivo embolization. When the distal abdominal aorta and pelvic arteries were occluded with EmboGel, within 1 minute of EmboClear infusion, patency of the aorta and most of the pelvic circulation was regained as noted by angiography. Embolization in the subclavian artery and numerous distal branches was rapidly dissolved by EmboClear. Finally, the carotid artery occluded with EmboGel regained patency after administration of EmboClear. Conclusions EmboGel is a dissolvable alginate-based biomaterial that can be used for numerous embolic applications. EmboGel can be selectively dissolved with EmboClear, a solution of alginate lyase and EDTA.
Plastic properties of Purkinje cells of the paramedian lobe of the cerebellum.

1. Activity of 35 Purkinje cells in the paramedian lobe of the cerebellum was investigated during the formation of motor conditioned reflexes to clicks in waking rabbits. Of this number 22 cells (63%) exhibited significant conditioned responses: 12 cells formed responses of activation type, 10 formed inhibitory responses. 2. The formation of activation responses was determined mainly (in 10 of 12 cells) by the excitatory action of electrodermal reinforcement on the cell. Inhibitory responses were formed in most cells depending on the sign of their initial response to the conditioned acoustic stimulus. 3. The response of 8 cells to conditioned stimulus was extinguished on the omission of reinforcement, and differentiation to unreinforced clicks with a different frequency of presentation from that of the conditioned stimulus was formed in 9 cells. Cells with conditioned activation responses responded to unreinforced acoustic stimuli by a decrease in discharge frequency, whereas cells with inhibitory responses responded by an increase in discharge frequency. 4. Some Purkinje cells which responded to electrodermal stimulation with “complex” spikes acquired the ability in the course of the combinations to respond to clicks with the same spikes. Usually from 1 to 3 “complex” spikes appeared to the first clicks in the combination and were accompanied by bursts of simple discharges followed by a phase of inhibition. Sometimes the phase of inhibition preceded the appearance of simple discharges.
Waffle House Restaurants hurricane response: A case study

Abstract Natural and man-made disasters present an increasing challenge to the management of supply chains for businesses, governments, and humanitarian response agencies. Sharing best practices enables the continued improvement of processes that can further impact lives and livelihoods in the event of a disaster. This case study highlights the experiences of Waffle House Restaurants, which has been nationally recognized for its response to hurricanes in the United States.
Collagen: Mobile Water Content of Frozen Fibers

From the change in the nuclear magnetic resonance splitting of heavy water in oriented wet collagen fibers at low temperatures, it is estimated that about 0.6 gram of heavy water per gram of collagen does not freeze. This estimate has been confirmed by a measurement of the heat evolved on melting "frozen" wet collagen. The water that does not freeze retains liquid-like mobility even at temperatures as low as -50°C.
Concurrent simulation of the eddying general circulation and tides in a global ocean model

Abstract This paper presents a five-year global simulation of HYCOM, the HYbrid Coordinate Ocean Model, that simultaneously resolves the eddying general circulation, barotropic tides, and baroclinic tides with 32 layers in the vertical direction and 1/12.5° (equatorial) horizontal grid spacing. A parameterized topographic wave drag is inserted into the model and tuned so that the surface tidal elevations are of comparable accuracy to those in optimally tuned forward tide models used in previous studies. The model captures 93% of the open-ocean sea-surface height variance of the eight largest tidal constituents, as recorded by a standard set of 102 pelagic tide gauges spread around the World Ocean. In order to minimize the impact of the wave drag on non-tidal motions, the model utilizes a running 25-h average to approximately separate tidal and non-tidal components of the near-bottom flow. In contrast to earlier high-resolution global baroclinic tide simulations, which utilized tidal forcing only, the simulation presented here has a horizontally non-uniform stratification, supported by the wind- and buoyancy forcing. The horizontally varying stratification affects the baroclinic tides in high latitudes to first order. The magnitude of the internal tide perturbations to sea surface elevation amplitude and phase in a large box surrounding Hawai’i is quite similar to that observed in satellite altimeter data, although the exact locations of peaks and troughs in the modeled perturbations differ from those in the observed perturbations.
On applied mathematics

This paper covers some aspects, problems, and episodes of applied mathematics intended to be enjoyable, instructive, and advisory to the young.