cssi/SciSciGPT-SciSciNet huggingface dataset:
Barriers to physical activity in the Hispanic community.

The purpose of this paper is to analyze barriers to leisure time physical activity in the Hispanic population in the U.S. Many studies have been conducted regarding this topic, primarily based on the general U.S. population. Fewer studies have concentrated specifically on Hispanics, where low levels of leisure time physical activity are reported. Research has usually stressed individual factors as barriers to exercise. A review of the literature addressing the different obstacles to physical activity will be presented within the context of immigration, poverty, and place of residency. This paper will attempt to explain why Hispanics tend to be less physically active and to make public health recommendations in order to minimize identified barriers. Suggestions and recommendations for future research that may help the understanding of the structural barriers will be provided.
ERYTHROPOIETIN LEVELS IN NEONATAL HYPERVISCOSITY

Top of pageAbstract In order to investigate the role of erythropoietin in the neonatal hyperviscosity syndrome serum levels of the hormone were measured with an in vitro enzyme immunoassay in 10 full-term neonates with hyperviscosity and compared to those found in 10 normal newborns, 5 prematures and 10 normal controls. The neonates with hyperviscosity had venous Hct from 65-80% and in 4 of them partial exchange transfusion was performed. Erythropoietin levels were low in all cases of hyperviscosity (mean 14miu/ml) ranging from undetectable to 28miu/ml (Normal controls 45miu/ml, fullterms 47.6miu/ml, preterms 28-3miu/ml). Reevaluation of erythropoietin levels in 3 neonates with hyperviscosity 6 months later showed an increase of the hormone level (mean 45miu/ml mean Hct 36%). These results seem to indicate that in neonatal hyperviscosity erythropoietin is decreased but its feed-back production mechanism remains intact.
The Influence of Aero-Derivative Combustor Turbulence and Reynolds Number on Vane Aerodynamics Losses, Secondary Flows, and Wake Growth

Exit surveys detailing total pressure loss, turning angle, and secondary velocities have been acquired for a fully loaded vane profile in a large scale low speed cascade facility. Exit surveys have been taken over a four-to-one range in Reynolds numbers based on exit conditions and for both a low turbulence condition and a high turbulence condition. The high turbulence condition was generated using a mock aero-derivative combustor. Exit loss, angle, and secondary velocity measurements were acquired in the facility using a five-hole cone probe at two stations representing axial chord spacings of 0.25 and 0.50. Substantial differences in the level of losses, distribution of losses, and secondary flow vectors are seen with the different turbulence conditions and at the different Reynolds numbers. The higher turbulence condition produces a significantly broader wake than the low turbulence case and shows a measurable total pressure loss in the region outside the wakes. Generally, total pressure losses are about 0.02 greater for the high turbulence case compared with the low turbulence case primarily due to the state of the suction surface boundary layers. Losses decrease moderately with increasing Reynolds number. Cascade inlet velocity distributions have been previously documented in an endwall heat transfer study of this same geometry. These exit survey measurements support our understanding of the endwall heat transfer distributions, the secondary flows in the passage, and the origin of losses.Copyright © 2006 by ASME
Anomalous properties of poly(methyl methacrylate) thin films in supercritical Carbon dioxide

Carbon dioxide produces an anomalous maximum in the swelling of poly(methyl methacrylate) (PMMA) thin films that is not present in bulk films, as shown with in-situ spectroscopic ellipsometry. This maximum and a corresponding minimum in refractive index are observed in regions of pressure where CO2 is highly compressible near the critical point. An effective excess thickness, determined from the height of the anomalous swelling maxima, increases proportionally with increasing initial film thickness, h0, in the range studied of 85 nm < h0 < 325 nm. Therefore, the anomalous swelling maxima suggest concentration inhomogeneities in the thin film, i.e., the onset of polymer/CO2 phase separation, that are influenced by the compressibility of the system and the confinement of the film. The PMMA swelling isotherms are insensitive to changing the substrate from silicon to gallium arsenide.
Purification of desmoglein II: a method for the preparation and f fractionation of desmosomal components

We have developed rapid and efficient methods for the isolation of desmosomes and the fractionation of their components. These methods involve the use of 6 M guanidine HCl to isolate the desmosomes from bovine epidermis, followed by hydroxyapatite column chromatography in the presence of SDS to fractionate the desmosomal components. All of the desmoplakins and desmogleins were purified at least partially by these procedures, and desmoglein II was purified to apparent homogeneity. We expect these procedures to facilitate a detailed biochemical analysis of the molecular components of desmosomes. In addition, these methods may be applicable to the purification of other plasma membrane domains involved in cell adhesion.
A real-time adaptive line enhancer hardware implementation designed for a plasma estimation application†

A real-time adaptive line enhancer hardware system has been implemented for noise cancellation in a nuclear fusion instrumentation project. The noise cancellation circuitry, realized with a standard digital signal processor (DSP) chip, uses a direct form adaptive filter and adapts using the least-mean-squares (LMS) algorithm. The noise cancellation circuitry adapts the noise filter weights to the line noise prior to an experiment. Upon initiation of the experiment, the adaption is stopped for the duration of the experiment. Experimental data with noise cancelling may be recorded during the experiment. After the experiment, noise filter weights may be read out to be included with the experimental record for possible later evaluation. The use of these hardware systems could significantly reduce the presently enormous requirements for off-line signal processing to extract plasma information. In this paper, real-time capabilities of the line enhancer circuitry for noise cancellation are demonstrated for simpl...
Prevalence of health conditions and predictors of mortality in oldest old Mexican Americans and non-Hispanic whites.

Abstract Background The oldest old represent a unique group of older adults. This group is rapidly growing worldwide and yet there are gaps in the knowledge related to their health condition. Ethnic differences in disease prevalence and mortality must be understood to better care for the oldest old. Objective To compare prevalence of common health conditions and predictors of mortality in oldest old Mexican Americans and non-Hispanic whites. Methods This study included 568 community-dwelling Mexican Americans (MA) aged 85 years and older from the Hispanic Established Population for the Epidemiological Study of the Elderly 2004–2005 and 933 non-Hispanic whites (NHW) of the same age from the Health and Retirement Study 2004. Measures included sociodemographic variables, self-reported medical conditions, activities of daily living (ADLs), and instrumental activities of daily living. Logistic regression analysis was used to examine 2-year mortality in both populations. Results Heart attack was significantly more prevalent in oldest old NHW compared with MA, regardless of gender. Conversely, diabetes was significantly more prevalent among MA men and women compared with their NHW counterparts. Compared with NHW men, MA men had significantly higher prevalence of cognitive impairment and hypertension. Additionally, prevalence of hip fracture was significantly higher for MA women compared with NHW women. Significant differences in ADL disability were observed only between both groups of women, whereas significant differences in instrumental activities of daily living disability were observed only between men. MA men and women had higher prevalence of obesity compared with NHW. Predictors of 2-year mortality for both ethnic groups included older age, male gender, and ADL disability. Cognitive impairment was a mortality predictor only for NHW. Similarly, lung disease was a predictor only for MA. Conclusion Health-related conditions that affect the oldest old vary by gender and ethnicity and entail careful evaluation and monitoring in the clinical setting. Better care requires inclusion of such differences as part of the comprehensive evaluation of the oldest old adults.
A Structural Continuum Constitutive Model for a Two-Phase Soft Tissue

Due to the complexity in determining multi-constituent tissue properties, most structural constitutive models for soft tissues focus on a single constituent. However, many tissues contain multiple load-bearing constituents, such as collagen fibers and smooth muscle (SM) cells. Moreover, to elucidate how observed changes in tissue components are related to altered net mechanical behavior at the tissue level, structural constitutive models require physiological relevant model parameters and formulations for changes in referential configuration when one component is physically removed. As an excellent example application that underscores these issues, we have examined the urinary bladder wall (UBW), which undergoes large deformations and exhibits highly nonlinear and anisotropic mechanical behavior [1,2]. Moreover, it undergoes profound remodeling in response to different pathologies such as spinal cord injury (SCI) [1,2].Copyright © 2010 by ASME
Plasma creatine phosphokinase levels in rats following lysergic acid diethylamide.

Lysergic acid diethylamide (LSD) injected intraperitoneally or intramuscularly did not increase rat plasma creatine phosphokinase (CPK) activity. LSD did not produce an increase in serum CPK activity in rats kept in a 2‡ C environment for 2 hrs. LSD also did not potentiate, in rats, the increase in plasma CPK activity produced by restraint at 2‡ C or 24‡ C. It is likely that the increases in serum CPK activity previously reported to occur in people who became psychotic following LSD ingestion are a consequence of the psychotic state itself rather than a direct effect of LSD.
GnRH-Induced Calcium and Current Oscillations in Gonadotrophs

Abstract The rat pituitary gonadotroph is a well-studied cell model for investigation of the oscillatory nature of calcium signaling in agonist-stimulated excitable cells. Cytosolic calcium levels ([Ca 2+ ] i ) in gonadotrophs are controlled by two distinct oscillators, a plasma membrane oscillator that generates extracellular calcium-dependent low-amplitude [Ca 2+ ] i spiking in unstimulated cells and an endoplasmic reticulum oscillator that is activated by calcium-mobilizing receptors for GnRH, endothelin, and pituitary adenylate cyclase-activating polypeptide. In this review, the characteristics of the spontaneous and agonist-induced calcium oscillations in gonadotrophs and the coordinate actions of the two oscillators during GnRH action discussed.
Electronic compass and vertical-angle measurement sensor: applications and benefits to the soldier system

The purpose of an electronic Compass and Vertical Angle Measurement (CVAM) sensor is to measure the attitude/orientation (i.e., azimuth, elevation, and cant; in terms of true North and local vertical) of the object to which it is attached. This measurement of orientation enables the addition of valuable functionality to the soldier system. Currently the Force XXI Land Warrior (FXXI LW) program is funding the development of a CVAM and its integration onto the Integrated Helmet Assembly Subassembly (IHAS) of the Land Warrior system. The primary intent of the FXXI LW effort is to produce a Head Orientation Sensor (HOS) that, when combined with data from a corresponding Weapon Orientation Sensor, enables a new function for the Land Warrior system known as Rapid Target Acquisition (RTA). The RTA functionality is only one of a set of soldier functions enabled by the CVAM. It is the objective of this paper to describe the CVAM/HOS and its various applications within the soldier systems. The introduction of the paper provides the history and background of the CVAM and its operation. The body of the paper is first focused on an overview of CVAM operation and the means by which it is to be integrated into various systems (to include helmets, advanced weapon sights, chemical sensing platforms, etc.). This will include the unique needs of the sensor such as calibration and parameter adjustment, and its key features that make it excel in its operational environment. The remainder of the paper focuses on the application of the CVAM to soldier systems; the benefits that CVAM offers to existing functions and the new functionality it enables. Various soldier functions and capabilities (new and pre-existing) are described. The paper concludes with a description of the status of the effort. This includes the developmental status of the CVAM/HOS, the validation of its design, and its integration into the IHAS and other weapon and sensing platforms.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
THE EFFECTS OF AWARENESS AND SUCCESSIVE INHIBITION ON INTEROCEPTIVE AND EXTEROCEPTIVE CONDITIONING OF THE GALVANIC SKIN RESPONSE

The general conclusion from Soviet studies of interoceptive conditioning has been that interoceptive conditioning is unconscious, established at a slower rate, and is more resistant to extinction than exteroceptive conditioning. Forty-eight paid volunteer subjects were classically conditioned to both interoceptive (0 and 50 degree C. water in an intubated balloon located between the bronchial and diaphragmatic constrictions of the esophagus) and exteroceptive CSs (256 and 512 Hz tones at 60 db). Significant interoceptive and exteroceptive conditioning of the GSR was obtained using responses occurring within the interstimulus or first interval (FIR) as well as the post-UCS or second interval (SIR). FIR conditioning progressed at a slower rate to interoceptive than to exteroceptive stimulation whereas SIR conditioning was equally effective to both modes of stimulation. Unawareness of interoceptive stimulation or their reinforcement contingencies tended to eliminate FIR but not SIR conditioning. Although not statistically supported, successive inhibitory-excitatory compounding of interoceptive and exteroceptive CSs indicated stronger response tendencies to the interoceptive CSs when equated to exteroceptive conditioning strength. These results demonstrate the complexity of GSR conditioning when CS modality, response types, and awareness of CS-UCS contingencies are considered.
Surface nucleation in the crystallization kinetics of phenanthrene multilayers on Al2O3(1120)

Abstract The glass-to-crystal transition in phenanthrene multilayers on Al2O3( 11 2 0 ) was studied using electronic absorption spectroscopy. Phenanthrene formed a glassy adlayer when adsorbed onto Al2O3( 11 2 0 ) at 90 K. The phenanthrene adlayer crystallized when annealed to 200 K and the electronic absorption spectrum changed dramatically upon crystallization. The pronounced alteration in the absorption spectrum for the S0 → S2 transition was used to study the kinetics of the crystallization process. The adlayer crystallization was dependent on phenanthrene coverage and the crystallization kinetics were consistent with surface nucleation followed by crystal growth into the phenanthrene multilayer. An Avrami analysis indicated that the surface nucleation sites were predetermined with a nucleation site density of 7 × 1011 cm−2 at the Al2O3( 11 2 0 ) surface. The velocity of crystallization in the phenanthrene multilayer was found to be temperature-dependent and measured velocities were 3.0 A s at 200 K and 9.2 A s at 202 K.
No evidence to support removal of asymptomatic impacted third molars in adolescents or adults.

Article Title and Bibliographic Information Interventions for Treating Asymptomatic Impacted Wisdom Teeth in Adolescents and Adults Mettes TG, Nienhuijs MEL, van der Sanden WJM, Verdonschot EH, Plasschaert AJM. Cochrane Database Syst Rev 2005;(2):CD003879 . Level of Evidence 1a Strength of Recommendation Grade B ⁎ Purpose To evaluate the effect of prophylactic removal of asymptomatic impacted wisdom teeth in adolescents and adults compared with the retention of these wisdom teeth. Source of Funding None noted Type of Study/Design Systematic review
Neurogenic and non-neurogenic mechanisms of plasma extravasation in the rat

Abstract We describe two distinct mechanisms for the enhancement of plasma extravasation in the knee joint of the rat. One is activated by bradykinin and is neurogenic; the other is activated by plateletactivating factor and is non-neurogenic. Bradykinin-induced synovial plasma extravasation is known to be dependent on the sympathetic postganglionic neuron terminal, and to involve prostaglandins, ATP, adenosine A 2 receptor action, and the attraction and activation of neutrophils. In this study we found that bradykinin-induced plasma extravasation also involves endothelium-derived relaxing factor; specifically we found that bradykinininduced plasma extravasation was antagonized stereospecifically by the inhibitor of endothelium-derived relaxing factor synthesis, N G -monomethyl- l -arginine. Perfused alone, platelet-activating factor produced an increase in synovial plasma extravasation which was markedly reduced by the platelet-activating factor receptor antagonists BN 52021 and WEB 2086 (these antagonists did not affect bradykinin-induced plasma extravasation). Platelet-activating factorinduced plasma extravasation was not affected by N G -monomethyl- l -arginine, indomethacin (a prostaglandin synthesis inhibitor), phenol 3-(5H-thiozolo[2,3b]quinazolin) (an A 2 receptor adenosine antagonist), dextran sulfate (an inhibitor of leukocyte rolling), hydroxyurea (a depletor of leukocytes), chronic sympathectomy or the depletion of unmyelinated afferent fibers. Of note, the magnitude of platelet-activating factor-induced plasma extravasation was increased by co-perfusion with prostaglandin E 2 and attenuated by co-perfusion with l -arginine; that is, two of the mediators involved in neurogenic bradykinin-induced plasma extravasation exerted an influence on non-neurogenic plasma extravasation. Separate mechanisms for bradykinin and platelet-activating factor plasma extravasation were further demonstrated in the streptozotocin-treated diabetic rat, in which there is a peripheral neuropathy. Neurogenic, bradykinin-induced plasma extravasation was greatly decreased in diabetic animals while non-neurogenic, platelet-activating factor-induced plasma extravasation was unchanged.
Models of side-to-end anastomoses: effects of angle and flow split.

Abstract The flow fields of model side-to-end vascular anastomoses, such as those used at the proximal end of axillofemoral and femoropopliteal grafts were analyzed. Clear plastic models of anastomoses of various angles (15°, 20°, 30°, 45°, 90°, 135°, 150°, 160°, 165°) were subjected to flow splits (flow exiting from the side branch/inflow) of 0.00 to 1.00, using water under steady-flow conditions. Nearwall flow was visualized by selective dye injection upstream. Regions of reversed, slow-moving nearwall fluid (separated flow) opposite the side-branch origin were evident at all angles, occurring at a flow split of 0.28 at 15° and progressively lower values at higher angles. A narrow ring of separated fluid formed about the anastomosis, entering the side branch. At flow splits of over 0.45, disturbed flow in the anastomotic region occurred in models with angles over 45°, due to the deflection of the mainstream toward the side branch, obliterating the near-wall flow evident at lower flow splits. The lack of large regions of near stagnation evident in our models at flow splits normally seen in clinical grafts (0.50 and above), especially at sharply angled anastomoses, may in part explain the clinical observation that hyperplasia occurs primarily at distal, as compared with proximal, anastomoses. Furthermore, the added platelet-wall contact caused by the disturbed flow at the proximal anastomosis may contribute to downstream hyperplasia.
Role of the Lungs in Maintaining Amino Acid Homeostasis

The relative contributions of skeletal muscle and the pulmonary bed in maintaining amino acid homeostasis were studied. Inasmuch as more than 60% of whole blood amino acid nitrogen is transported as glutamine and alanine, the flux of these two amino acids across the lungs (n = 20) and hindquarter (n = 20) was determined in the postabsorptive adult rat. Both skeletal muscle and the lungs released net amounts of glutamine and alanine in the postabsorptive state. Blood flow to the hindquarter was approximately 16% of cardiac output (3.8 +/- 0.3 cc/100 g BW/min), while pulmonary blood flow (cardiac output) was 23.7 +/- 1.7 cc/100 g BW/min. Thus, despite a lower glutamine concentration difference across the lungs (-32 +/- 6 mumol/liter) compared with the hindquarter (-59 +/- 10 mumol/liter (p less than 0.01), the lungs released significantly more glutamine (741 +/- 142 nmol/100 g BW/min) than the hindquarter (208 +/- 39 nmol/100 g BW/min) (p less than 0.01) because of the significantly higher pulmonary blood flow. Similarly, the concentration difference for alanine across the lungs was less than that of the hindquarter (-24 +/- 8 mumol/liter vs -60 +/- 12 mumol/liter, p less than 0.01) but the lungs released significantly more alanine than the hindquarter (553 +/- 159 nmol/100 g BW/min vs 221 +/- 41 nmol/100 g BW, p less than 0.01. Compositional studies demonstrated that the hindquarter comprises 40% of total body muscle mass in the rat; thus both total skeletal muscle mass and the lungs contribute approximately equally to the maintenance of blood glutamine and alanine levels.(ABSTRACT TRUNCATED AT 250 WORDS)
A thermoelectric cuvette cooler for optical studies in cryobiochemistry

Abstract The inflexibility, inconvenience, and large cost of a liquid nitrogen-cooled gaseous temperature regulator can be circumvented using Peltier-junction technology. The advantages offered in such a system are apparent, and could easily open the door to further capitalization of the elegant cryoenzymology techniques pioneered by Douzou.
Three dimensional morphology of cementite precipitates

Conventional light and electron microscopy techniques usually allow for characterization of microstructures in only two dimensions. This is a serious impediment to understanding the three dimensional morphology of microstructural features. This paper presents the results of a deep etching study of cementite precipitates in a model alloy composed of Fe-1.34 wt.% C-13.1 wt.% Mn. The high carbon level enables a large volume fraction of cementite precipitates to be produced while the high manganese and carbon levels together suppress the martensite start temperature to below room temperature. During deep etching of this alloy, the austenitic matrix is preferentially removed and the morphology of the cementite precipitates is revealed. This also enables complimentary crystallographic and interfacial structure studies which are underway. Although previous investigations used deep etching as a supplementary technique for characterizing cementite plates, the current work places emphasis on determining the three dimensional morphology of both grain boundary and intragranular precipitates previously categorized under the two dimensional Dube morphological classification system.
De Auguste Comte a Émile Zola: la teoría literaria modernista de Manuel González Prada

Se debe decir que Manuel Gonzalez Prada* (1844–1918) no fue hombre de accion sino, siendo un hombre introvertido que vivio entre sus libros y revistas, un hombre de ideas, de teorias.1 Durante el p...
Analgesic effect of intramuscular and oral nalbuphine in postoperative pain.

In a double-blind study using patients' subjective reports as indices of analgesia, the relative analgesic potency of intramuscular and oral nalbuphine was determined in 104 postoperative patients. Effects of single doses of 3 and 9 mg of intramuscular nalbuphine were compared with those of 15- and 45-mg oral doses of nalbuphine by means of a parallel study design (26 patients per treatment group). When both intensity and duration of analgesia are considered (i.e., total analgesic effect), oral nalbuphine is 1/4 to 1/5 as potent as intramuscular nalbuphine. In terms of peak effect, however, oral nalbuphine is only 1/10 as potent. The oral/parenteral potency ratio for total effect is close to those obtained by Houde et al. in studies of morphine (1/6), metopon (1/5), hydromorphone (1/5), and oxymorphone (1/6) and suggests that oral nalbuphine undergoes substantial biotransformation on first pass through gut mucosa and liver. Since intramuscular nalbuphine is approximately equipotent to morphine, it should be feasible to equal the analgesia induced by the usual intramuscular doses of morphine with reasonable oral doses of nalbuphine. Although nalbuphine is a mixed agonist/antagonist analgesic, no psychotomimetic reactions were observed.
Combinatorial properties of planar spaces and embeddability

Abstract Let S be a planar space in which all planes V are finite and contain N(V) + 1 lines through each point p ϵ V. Our main result states that, if |L| ⩾ (2N(V) + 5) 3 for any plane V and any line L of V, then N(V) is a constant N and S is embeddable in a projective space. This will be a consequence of several other, more general results, giving sufficient conditions for a planar space S to be locally projective and/or to satisfy the bundle property.
Crystal Structure of a Polymeric Immunoglobulin Binding Fragment of the Human Polymeric Immunoglobulin Receptor

The polymeric immunoglobulin receptor (pIgR) is a type I transmembrane protein that delivers dimeric IgA (dIgA) and pentameric IgM to mucosal secretions. Here, we report the 1.9 A resolution X-ray crystal structure of the N-terminal domain of human pIgR, which binds dIgA in the absence of other pIgR domains with an equilibrium dissociation constant of 300 nM. The structure of pIgR domain 1 reveals a folding topology similar to immunoglobulin variable domains, but with differences in the counterparts of the complementarity determining regions (CDRs), including a helical turn in CDR1 and a CDR3 loop that points away from the other CDRs. The unusual CDR3 loop position prevents dimerization analogous to the pairing of antibody variable heavy and variable light domains. The pIgR domain 1 structure allows interpretation of previous mutagenesis results and structure-based comparisons between pIgR and other IgA receptors.
An evaluation of squamous cell carcinoma antigen in patients with cervical squamous cell carcinoma

In a prospective study, serum concentrations of squamous cell carcinoma antigen, a subfraction of tumor antigen (TA-4), were determined by radioimmunoassay from healthy donors, pregnant women; and subjects with various benign and malignant gynecologic diseases. Ninety-six percent of 99 healthy persons including all 52 female controls, the 15 pregnant patients, and all 23 subjects with benign gynecologic tumors, had squamous cell carcinoma antigen levels 2.0 ng/ml. Declining and rising levels of squamous cell carcinoma antigen, which were determined sequentially in nine cases of cervical carcinoma that were associated with elevated pretreatment levels of squamous cell carcinoma antigen, correlated with regression and progression of the disease. Serial serum levels of squamous cell carcinoma antigen provide a noninvasive means of monitoring the effects of individual therapy in patients with cervical squamous cell carcinoma.
The Role of Genetics in the Provision of Essential Public Health Services

States include genetics services among their public health programs, but budget shortfalls raise the question, is genetics an essential part of public health? We used the Essential Services of Public Health consensus statement and data from state genetics plans to analyze states' public health genetics programs. Public health genetics programs fulfill public health obligations: birth defects surveillance and prevention programs protect against environmental hazards, newborn screening programs prevent injuries, and clinical genetics programs ensure the quality and accessibility of health services. These programs fulfill obligations by providing 4 essential public health services, and they could direct future efforts toward privacy policies, research on communications, and rigorous evaluations.
Detection of multiple antigenically related proteins from various rat tissues by monoclonal antibodies against 3α-hydroxysteroid dehydrogenase

Abstract Mouse hybridomas were prepared by fusing myelomas and spleen cells from mice immunized with purified rat 3α-hydroxysteroid dehydrogenase. Hybridomas secreting monoclonal antibodies against 3α-hydroxysteroid dehydrogenase were selected by indirect enzyme-linked immunoassay and then subcloned by limiting dilution. From two mice we have obtained four positive hybridomas, three secreting high affinity immunoglobulin (Ig) G1 and one secreting IgM. Only two of these monoclonal antibodies (MAbs 3G6 and 7D3, both IgG1) recognized denatured enzyme and, therefore, were used for further immunoblotting experiments. MAb 7D3 recognized a structurally related mouse enzyme, but not the human enzyme, whereas monoclonal antibody 3G6 recognized a human enzyme, but not the mouse enzyme. When these two monoclonal antibodies were used in immunoblotting to survey the expression of 3α-hydroxysteroid dehydrogenase in rat liver and a number of other tissues, striking differences were found in the protein band patterns in kidney, lung, and testis. Both MAbs 7D3 and 3G6 recognized 3α-hydroxysteroid dehydrogenase, a 34-kDa protein, in livers from female and male rats. In lung MAb 7D3 recognized a protein of the same size as the liver protein, whereas MAb 3G6 recognized a 34-kDa protein plus another protein of 36 kDa. In kidney only MAb 3G6, but not MAb 7D3, recognized a 34-kDa protein. Conversely, the 34-kDa protein in testis was recognized by MAb 7D3, but not by MAb 3G6. These findings suggest the existence of multiple antigenically related proteins in different tissues.
Total synthesis of trifluorobutyryl-modified, globally protected sialyl Lewis x by a convergent [2+2] approach

Structural and quantitative changes in the expression of sialic acid residues on the surface of eukaryotic cells profoundly influence a broad range of biological processes including inflammation, antigen recognition, microbial attachment, and tumor metastasis. Uptake and incorporation of sialic acid analogues in mammalian cells enable structure-function studies and perturbation of specific recognition events. Our group has recently shown that a trifluorobutyryl-modified sialic acid metabolite diminishes the adhesion of mammalian cells to E and P-selectin, presumably by leading to the expression of fluorinated sLex epitopes on cell surfaces, and interfering with the sLex-selectin interactions that are well known in mediating tumor cell migration.1 For studies directed towards understanding the molecular basis of this reduced adhesion, chemical synthesis of trifluorobutyrylated sialyl Lewis x (C4F3--sLex) was crucial. We have developed a highly efficient [2+2] approach for the assembly of C4F3-sLex on a preparative scale that contains versatile protective groups allowing the glycan to be surface immobilized or solubilized as needed for biophysical studies to investigate selectin interactions. This strategy can, in principle, be used for preparation of other N-modified sLex analogues.
A wide-band structure for high-power traveling-wave tubes

In an effort to overcome the low power handling capabilities of the conventional wire helix considerable effort has been devoted to the development of filter-type slow-wave structures for use in high-power traveling-wave amplifiers. However, the shortcoming of the various filter-type structures such as the disk-on-rod and the apertured disk, is their inherently narrow bandwidth. For a filter-type structure operating at a center frequency of 3000 mc, the maximum attainable bandwidth is approximately 10 per cent or 300 mc. With the type of structure considered herein it is hoped to achieve a bandwidth of approximately 30 per cent at 3000 mc. The helical waveguide structure is composed of a helical tape wound inside a cylinder. The hole for the passage of the beam would normally be located along the axis of the helical tape. However, the field analysis indicates that stronger coupling might be obtained by placing the beam hole somewhat off center. In order to gain maximum coupling to the beam, several off-center electron beams would be located at a radius corresponding to that of the maximum of the electric field. The cavities are coupled continuously by the helical tape. The bandwidth, i.e., dispersion curve, should approach that of the conventional wire helix except in the dispersive region because the waveguide has a cutoff. The power handling capability clearly is greater than that of the wire helix. However, the impedance will be lower, resulting In a lower gain parameter C. Other factors such as a higher permissible value of (I o /V o ) and a more nearly constant electric field along the spiral contribute to a higher gain parameter. In fact, the zero-order mode (β = O) will have no variation of electric field across the cavity. Because of the complexity of an exact mathematical analysis some approximations have been made. The assumption used in this analysis is that the pitch of the helical tape is considered small compared to its diameter. Each section of the waveguide is considered as a cylindrical cavity of height h, where h = 2 P and P = pitch of the tape. This is a valid assumption where the pitch is small, as the end faces of the cavities are essentially perpendicular to the cylindrical enclosure. The helical surface is considered to be a Riemann surface wherein φ is a periodic and single-valued coordinate; however, in the usual cylindrical coordinate system φ is a nonperiodic coordinate. Thus the fields are multi-valued functions of the coordinate φ. Under the above conditions and the generalization of the Bessel-function order n to its general parameter p, the familiar cylindrical wave-guide equations may be used. Under this transformation p is capable of assuming nonintegral values. On the basis of the theoretical analysis presented herein the helical waveguide structure seems best suited for high-frequency use, especially in the frequency range of 5–10 kmc. The bandwidth and gain approach those of the helix-type traveling-rave tube.
The Fatherhood Scale.

This article reports on the initial validation of the Fatherhood Scale (FS), a 64-item instrument designed to measure the type of relationship a male adult had with his father while growing up. The FS was validated using a convenience sample of 311 males. The assessment packet contained a demographic form, the Conflict Tactics Scale (2), Self-Esteem Scale, and the Fatherhood Scale. A series of factor analysis resulted in 13 factors accounting for 75% of the variance. Factors with high correlations that were theoretically related to other factors were combined resulting in nine subscales measuring positive and negative paternal engagement, fatherhood roles, and paternal emotional responsiveness. The subscales attained high levels of internal consistency reliability, with alpha levels ranging from 0.80 to 0.96. The scale has an overall reliability of 0.98, and showed preliminary evidence of differentiating between groups of men on self-esteem and intimate partner violence. The FS is a new assessment tool de...
Chemical Modification of ProRoot MTA to Improve Handling Characteristics and Decrease Setting Time

Abstract Mineral trioxide aggregate (MTA) fulfills many of the ideal properties of a root-end filling material. However, the composition of this material often makes MTA difficult to use, a direct result of its granular consistency, slow setting time, and initial looseness. Additives used by the Portland cement (PC) industry to increase PC’s plasticity and decrease its setting time were added first to PC and then to gray MTA in an attempt to improve MTA’s handling characteristics, with the combination providing the best handling characteristics tested for its effect on compressive strength (for changes in the original material’s properties) and decrease in setting time. An admix of 1% methylcellulose and 2% calcium chloride resulted in a mix of chemically modified MTA that, when compared with unmodified MTA, (1) handled similarly to a reinforced zinc oxide–eugenol cement, (2) gave an approximately equal compressive strength, and (3) set one third faster (57 ± 3 minutes).
The Illinois Agricultural Industries Forum

HE Illinois Agricultural Industries Forum is a two-day seminar program for leaders and decision makers in the agricultural industries field. The program has been held each year for the last 11 years in late January or early February, except for one year. The primary theme of the Forum has been related to change in the agricultural industries or anticipated change, implications, and alternatives for development and public policy. Its first theme, in 1959, "Tomorrow's Farm Challenge to Food and Agricultural Service Industries," was an idea of interest throughout the succeeding decade. Themes generally have related to agricultural development potentials, to financing, new products, new systems, anticipated changes ahead. The Forum's theme this year was "Issues and Choices in a Changing Agriculture," as viewed by speakers, panel members, and other participants.
Normal cellular levels of synaptophysin mRNA expression in the prefrontal cortex of subjects with schizophrenia.

Abstract Background: Previous studies have reported that the 38-kd synaptic vesicle-associated protein, synaptophysin, is decreased in the prefrontal cortex of subjects with schizophrenia. Methods: To determine whether the decreased protein levels reflect diminished expression of the synaptophysin gene by prefrontal cortex neurons, we used in situ hybridization histochemistry to determine the cellular levels of synaptophysin messenger RNA in prefrontal cortex area 9 from 10 matched pairs of schizophrenic and normal control subjects. Results: Neither the density of neurons with detectable levels of synaptophysin messenger RNA nor the mean level of synaptophysin messenger RNA expression per neuron differed between schizophrenic and control subjects in any cortical layer. Conclusions: These findings indicate that the expression of synaptophysin messenger RNA is not altered in this brain region in schizophrenia. Consequently, reduced levels of synaptophysin protein in the prefrontal cortex of subjects with schizophrenia are more likely to reflect either posttranscriptional abnormalities of synaptophysin in prefrontal cortex neurons or a diminished number of axonal projections to the prefrontal cortex from other brain regions.
PHYSIOTHERAPY AND OCCUPATIONAL THERAPY FOR JUVENILE CHRONIC ARTHRITIS: CUSTOM AND PRACTICE IN FIVE CENTRES IN THE UK, USA AND CANADA

Physiotherapy and occupational therapy are widely accepted as being of central importance for the treatment of juvenile chronic arthritis (JCA). However, these approaches have rarely been subject to critical scrutiny. The aims of this report are to highlight some of the inter-centre similarities and differences observed in the implementation of physical and occupational therapy for JCA, and to emphasize the need for scientifically controlled research in this area. During a series of visits to several paediatric rheumatology units in the UK, USA and Canada, three aspects of the service were noted: treatment philosophy, physical interventions used for the treatment of JCA and quality-of life and independence training activities. There was general consensus with the philosophy that early physical intervention was a vital part of the treatment plan for JCA, although all therapists were concerned that compliance with treatment modalities was poor. Differences between units in the approach to acute arthritis, the use of foot othoses and wrist splints, the treatment of joint contractures and the use of general quality-of-life training activities were noted. Although it was widely recognized that controlled research into the efficacy of physical intervention was needed, no centre had a co-ordinated plan for such investigations. Keywords: Juvenile chronic arthritis, Physiotherapy, Occupational therapy
The effect of the corporate alternative minimum tax on investment in oil and gas exploration and development

Abstract This paper investigates the assertion that the U.S. corporate alternative minimum tax system diminishes exploration and development investment by U.S. corporations operating in the extractive petroleum industry. The analysis is based on an after-tax investment model in which number of wells drilled and exploration risk are endogenous variables. The model is solved using 1) the values of the relevant tax parameters specified by the tax code and 2) empirical estimates of the non-tax parameters and exogenous variables. The analysis shows that the alternative minimum tax has reduced by 9% the optimal number of exploration wells as compared to the optimal number of exploration wells prior to the introduction of the alternative minimum tax. The analysis also shows that the alternative minimum tax has 1) reduced the optimal level of exploration risk and 2) increased the importance of well-designed incentive compensation agreements for firms operating in the extractive petroleum industry.
Fatigue Induced Risk of Spinal Instability during Manual Materials Handling

Risk of occupational low-back disorders may be related to spinal stability achieved during manual materials handling. Stability is controlled and influenced by trunk muscle stiffness, antagonistic co-contraction and reflex response. Fatigue influences each of these factors, suggesting that fatigue may compromise spinal stability. A biomechanical model of spinal stability and experimental data were implemented to evaluate the effects of fatigue. EMG and trunk kinematics from 21 healthy subjects were recorded during static trunk extension exertions and sudden-load trials in fatigued and unfatigued states. The model predicted dramatic reduction in spinal stability associated with fatigue related decrement in paraspinal muscle stiffness and force generating capacity. Empirical data supported the model predictions, demonstrating increased antagonistic co-contraction during fatigued exertions. Results suggest risk of low-back injury from loss of spinal stability is increased during fatigue from manual materials...
When Application Leads Theory: A Design Orientation for Teaching and Research in Information Technology

This paper presents the position that application of knowledge now precedes theory building in information technology‐related fields. This reversal, caused by the accelerated pace of new knowledge creation, has important implications for the conduct and dissemination of research, and calls for a restructuring of information technology curricula. Rather than adapt to this new academic environment from the perspective of a critic, user, or policy maker, researchers and curriculum builders in information technology should adopt the perspective of a designer. An instructional/research vehicle well suited to this task is group hypermedia. Examples from research in High Definition Television and graduate design education illustrate these propositions. Although the velocity with which new information is produced cannot and should not be slowed, diversity of inputs to the research effort in information technology must be maintained. If not, creativity, at both the societal and individual level, will suffer.
A test of the nitrogen-limitation hypothesis for retarded eukaryote radiation: Nitrogen isotopes across a Mesoproterozoic basinal profile

Abstract Nitrogen limitation caused by trace metal scarcity under euxinic ocean conditions has been proposed as an explanation for the delayed radiation of eukaryotes until at least the late Mesoproterozoic. However, evidence for how the nitrogen cycle was operating during the middle Precambrian is, so far, rare. More specifically, it is unknown which steps in the biogeochemical nitrogen cycle, e.g. nitrogen fixation, nitrification or ammonification, were rate-limiting and thus controlling microbial community structures. The Mesoproterozoic Belt Supergroup in western Montana hosts a variety of facies ranging from shallow to deep water and thus offers the opportunity to address this issue. Bulk δ 15 N values show a clear trend from −1‰ in the deepest part of the basin to +5‰ along basin margins, which suggests that coastal areas were sufficiently oxygenated for aerobic nitrogen cycling. The total fractionation of carbon isotopes between carbonate and organic carbon (Δ 13 C) increases from 20‰ to 32‰ in the same direction, possibly indicating an ecological response to redox stratification and nitrogen speciation. Evidence from the Belt Supergroup is thus consistent with the idea that nutrient availability may have restricted early eukaryotic organisms to a narrow range of habitats, which thus prevented a global rise to ecological dominance until concentrations of fixed nitrogen increased in the global open ocean.
Two-stage exchange knee arthroplasty: does resistance of the infecting organism influence the outcome?

Background Periprosthetic joint infection after TKA is a challenging complication. Two-stage exchange arthroplasty is the accepted standard of care, but reported failure rates are increasing. It has been suggested this is due to the increased prevalence of methicillin-resistant infections.
Status of the development of rechargeable lithium cells

The progress in the development of the ambient temperature lithium - titanium disulfide rechargeable cell under development at the Jet Propulsion Laboratory is described in this paper. Originally aimed at achieving a specific energy of 100 Wh/kg, 'AA' cells have demonstrated 125 Wh/kg at the C/3 discharge rate. The results of evaluating cell design parameters are discussed and cycling test data are also included in the paper. Safety tests results at various over-charge and over discharge conditions and rates proved to be uneventful. The test results of cell with built-in overcharge mechanism proved the concept was feasible. Replacing the lithium foil electrode with a Li(x)C resulted in a capacity at 1mA/cm(exp 2) of 200 mAh/gm and 235 mAh/gm at 0.167 mA.
Chromosomes in a marsupial (Potorous tridactylis) tissue culture.

THE chromosome constitution of marsupial, Potorous tridactylis, was described by Sharman and Barber1. The males have five pairs of autosomes and three sex chromosomes. The low number of chromosomes plus the fact that the same investigators reported somatic pairing made this species desirable for genetic studies in tissue cultures.
The Response of a Zonally Symmetric Atmosphere to Subtropical Thermal Forcing: Threshold Behavior

We consider the response of a zonally symmetric atmosphere to a thermal forcing that is localized in the subtropics. Specifically, the equilibrium temperature distribution has a local subtropical peak and is flat elsewhere, including at the equator. On the basis of inviscid steady-state theory, it is argued that the response to such forcing is one of two distinct types. Below a threshold forcing, the atmosphere adopts a steady state of thermal equilibrium with no meridional flow. With supercritical forcing, this state breaks down and a strong meridional circulation is predicted. The threshold forcing value is that at which the absolute vorticity of the zonal flow (in gradient balance with the equilibrium temperatures) vanishes at the upper boundary. These inviscid predictions are tested in a zonally symmetric numerical model; while the model viscosity shifts the threshold and otherwise modifies the response, the threshold is clearly evident in the model behavior.