cssi/SciSciGPT-SciSciNet huggingface dataset:
Stability robustness margin computation for structured real-parameter perturbations

An efficient computational method is presented for stability robustness analysis with structured real-parameter perturbations. A generic model of a class of uncertain dynamical systems is used as an example. The parameter uncertainty is characterized by a real scalar perturbation variable. Multilinearity of the closed-loop characteristic polynominal is exploited to permit application of the mapping theorem to calculate the stability robustness margin. It is found that the stability boundary of the perturbation variable exhibits sensitive geometry in the frequency domain, which renders problematic the task of minimizing this variable as a function of frequency. This difficulty is avoided by calculating the minimum distance to the image of the uncertainty domain over frequency as a function of the perturbation. It is also shown that a certain class of uncertain dynamical systems has the required multilinearity property and is thus amenable to the proposed technique.
ORBITAL SOLUTIONS AND ABSOLUTE ELEMENTS OF THE ECLIPSING BINARY EE AQUARII

EE Aqr is a 7.9 mag Algol variable with a 12 hr orbital period. The Wilson-Devinney program is used to simultaneously solve 11 previously published light curves together with two existing radial velocity curves. The resulting masses are M 1 = 2.24 ± 0.13 M ☉ and M 2 = 0.72 ± 0.04 M ☉, and the radii are R 1 = 1.76 ± 0.03 R ☉ and R 2 = 1.10 ± 0.02 R ☉. The system has the lower-mass component completely filling its Roche lobe. Its distance from Hipparcos observations is 112 ± 10 pc. An improved ephemeris is derived, and no deviations in the period over time were seen. Light and velocity curve parameters, orbital elements, and absolute dimensions are presented, plus a comparison is made with previous solutions.
Natural resource damage assessment : Economics and settlements

Natural Resource Damage Assessment (NRDA) is the process of calculating the damages from releases of hazardous substances at one or more contaminated sites. In this paper the difference between “Superfund” remediation anal subsequent clean up, and clean up in the context of NRDA (restoration) is explained. After a review of the basics of NRDA economics, some cases for which the economics details are known are examined, at least to a degree. Though the veil of secrecy cloaking legal cases sometimes makes it difficult to learn details, a brief summary of some of the details on a few NRDA cases that have “concluded” in recent years allows a glimpse whether site‐specific damage estimates and settlement amounts seem to relate to contamination levels. Economics appears to be important in reaching these settlements, but whether settlement amounts relate strongly to contamination, or levels at particular sites, or more strongly to other factors cannot be seen from the limited information available at this time.
An exploration of body dissatisfaction and perceptions of Black and White girls enrolled in an intervention for overweight children

Silhouette measures are one approach to assessing body dissatisfaction in children, although little is known about their use among racially diverse, overweight girls seeking weight-loss treatment. This study assessed racial differences in body dissatisfaction and body size perceptions of 58 girls (ages 6-11, 66% Black, 34% White) participating in a randomized trial for pediatric overweight. Body dissatisfaction did not differ between races; 99% of girls reported an ideal figure smaller than their current one. Black girls selected a larger silhouette to represent their ideal body size, and most girls in both racial groups underestimated their actual size. Outcomes strengthen the argument that, despite an overall preference for a larger body size, obesity might mitigate cultural factors that protect Black girls from body dissatisfaction. Additional research is needed to enhance understanding of children's body size perceptions and dissatisfaction to inform assessment and treatment of pediatric obesity and associated disordered eating symptoms.
Subjective response to respirator type: effect of disease status and gender.

Objective To assess the effect of respirator type and user characteristics (eg, health status) on the subjective response to respirator use. Methods The subjective responses for multiple domains were evaluated in 104 volunteers performing work tasks in a simulated work environment. Each used a dual cartridge half face mask and a filtering facepiece (N95) respirator. The study population was recruited to include four groups (normal respiratory status, mild asthma, chronic obstructive pulmonary disease, or chronic rhinitis). Mixed model regression analyses determined the effects of respirator type, disease, gender, and age. Results Half face mask produced more adverse subjective response than the N95 for most scales. There were significant interactions such that disease status modified the effect of respirator type. In general, women reported greater adverse ratings than did men. Conclusions The effect of respirator type depends on disease status. Respirator design evaluation panels should include persons with mild respiratory disease.
Si ad-dimer interactions with steps and islands on Si(001)

The interactions of adsorbed Si dimers with steps and islands on Si(001) are quantified using atom-tracking STM. Diffusing dimers are reflected from steps, sides of islands, and certain surface defect structures. Site-specific free energies are extracted from measurements of lattice-site occupation probabilities of dimers trapped between these reflecting barriers. Relative to the free energy of isolated dimers on a terrace, dimers located at the first lattice site next to SA steps and the sides of islands are bound by 0.05 eV. The binding decreases to half that at the second lattice site, and is indistinguishable from the free-terrace value at a distance of three or more lattice sites.
Activity and selectivity of 1-hexene conversion on SAPO-11 and Pd/SAPO-11

Abstract The activity and selectivity patterns for 1-hexene reactions have been compared in the temperature range of 150-450°C for four different kinds of acidic zeolites (H-mordenite, HZSM-5, SAPO-11 and Pd/SAPO-11) differing both in acid properties and geometric structure. At lower reaction temperatures (150-175°C) the predominate reaction pathway was double bond shift (DBS) and was not influenced by the type of catalyst. At higher temperatures significant shifts in selectivity were observed from DBS to cracking (c) or skeletal rearrangement (SR) depending on the type of catalyst. H-mordenite maintained DBS even at the highest temperature, HZSM-5 produced significant quantities of cracked alkenes, and SAPO-11 was intermediate. The Pd/SAPO-11 gave enhanced DBS selectivity and less cracking at higher temperatures in comparison to unloaded SAPO-11. In general, hydrogen was found to inhibit DBS and promote cracking reactions. Temperature-programmed desorption patterns were also determined. Desorption peaks for all materials were found at around 170°C, 240°C and 330°C, with a significant loss of strong Bronsted acidity upon palladium loading on SAPO-11. A selectivity correlation at 350°C showed strong dependence of DBS and cracking on total acidity, with a shift from DBS to cracking with increasing acidity. The reaction seems well suited for investigation of the interrelation between pore structure and surface acidity in terms of these selectivity factors.
Some effects of oxygen impurities on AlN and GaN

Oxygen is a common substitutional impurity in both AlN and GaN crystals. In the wurtzite 2H phase it can be present in AlN up to concentrations of 1 x 10 21 /cm 3 while in GaN it can reach concentrations of 3 × 10 22 /cm 3 . These high concentrations of oxygen affect the luminescence, the optical absorption, the thermal conductivity, and the crystal perfection. The effects are somewhat similar in AlN and GaN. Representative experimental data will be presented to demonstrate the similarities, and to show how the oxygen content may be estimated from these property measurements.
Is idiopathic dementia a regional vitamin deficiency state

We hypothesize that some cases of idiopathic dementia are due to a gradual undernourishment of the brain with water-soluble vitamins. This occurs because the choroid plexus and possibly other transport loci in the central nervous system become unable to transport water-soluble vitamins from blood into the central nervous system in adequate amounts. If this testable hypothesis is correct, direct injections of vitamins into the ventricular cerebrospinal fluid should ameliorate the development of dementia.
pH-Dependent cis --> trans isomerization rates for azobenzene dyes in aqueous solution.

Azobenzenes can function as molecular switches driven by their unusual cis ↔ trans photoisomerization properties. The stability of an azobenzene-based switch depends on its rate of thermal relaxation, which is known to depend on the solvent environment, but few kinetic studies in aqueous media have been reported. We use nanosecond UV laser flash photolysis−transient absorption spectroscopy to measure thermal cis → trans isomerization rates for mono- and disubstituted p-aminoazobenzenes and p-hydroxyazobenzenes in water at 23 °C over the pH range of 4 to 11. Observed absorption transients are fit to first-order relaxation rate constants between 105 and 101 s−1, which is generally much faster than in nonpolar solvents, and the relaxation rates vary systematically and predictably with pH as the equilibrium shifts to ionized forms of the dyes that isomerize much more rapidly. Acid ionization constants for these dyes determined from our kinetic mechanism are compared with the pH dependence of their equilibrium...
Relative thermochemical stabilities and reactivities of benzo[a]pyrene and selected isomers

Abstract Gas-phase standard enthalpies of formation are calculated for benzo[ a ]pyrene and thirty-two isomeric polycyclic aromatic hydrocarbons including compounds having four-five- and seven-membered rings. Additionally, reactivity data are summarized and include experimental ionization potentials, Huckel highest occupied molecular orbitals and selected reactivity indices. These data are compared with levels of those C 20 H 12 hydrocarbons reported in the atmosphere. These thermodynamic and kinetic parameters are useful reference points for understanding the stabilities of airborne PAH. Additionally, the data tabulations may be useful in predicting the existence of PAH not yet reported in environmental samples.
Applications of high energy ion beam techniques in environmental science: Investigation associated with glass and ceramic waste forms

Abstract High energy ion beam capabilities including Rutherford backscattering spectrometry (RBS) and nuclear reaction analysis (NRA) have been very effectively used in environmental science to investigate the ion-exchange mechanisms in glass waste forms and the effects of irradiation in glass and ceramic waste forms in the past. In this study, RBS and NRA along with SIMNRA simulations were used to monitor the Na depletion and D and 18 O uptake in alumina silicate glasses, respectively, after the glass coupons were exposed to aqueous solution. These results show that the formation of a reaction layer and an establishment of a region where diffusion limited ion exchange occur in these glasses during exposure to silica-saturated solutions. Different regions including reaction and diffusion regions were identified on the basis of the depth distributions of these elements. In the case of ceramics, damage accumulation was studied as a function of ion dose at different irradiation temperatures. A sigmoidal dependence of relative disorder on the ion dose was observed. The defect-dechanneling factors were calculated for two irradiated regions in SrTiO 3 using the critical angles determined from the angular yield curves. The dependence of defect-dechanneling parameter on the incident energy was investigated and it was observed that the generated defects are mostly interstitial atoms and amorphous clusters. Thermal recovery experiments were performed to study the damage recovery processes up to a maximum temperature of 870 K.
Factors That Influence Separated and Divorced Parents' Sharing of Personal Information With Dating Partners

Separated and divorced parents struggle with the best ways to manage personal information with new partners. Thirty-five separated or divorced parents were interviewed to determine the factors that influence whether and how they reveal information about their divorces, children, and other details about their former marriages to dating partners. Findings revealed that, in early dating relationships, people privileged openness but also engaged in impression management. As relationships became more serious, parents and dating partners relied on implicit and explicit rules guiding their disclosures about their ongoing relationships with ex-spouses.
Sodium-Carbonate-Assisted Supercritical Water Oxidation of Chlorinated Waste

Supercritical water oxidation (SCWO) is emerging as a promising technology for the destruction of organic wastes. However, corrosion is a severe problem for chlorinated wastes because of the formation of hydrochloric acid. Recently, it was proposed that the addition of Na 2 CO 3 significantly reduces the corrosion. This work examines the effect of Na 2 CO 3 on the oxidation kinetics of phenol and 2-chlorophenol in supercritical water. The kinetics data in the absence of Na 2 CO 3 are verified to conform to the literature data. New data in the presence of Na 2 CO 3 show that the oxidation is highly enhanced, which may be due to a combination of the catalytic effects of Na 2 CO 3 and removal of HCl by Na 2 CO 3 . If all other kinetic parameters are unchanged, the activation energy of 2-chlorophenol decomposition decreases from 11.5 kcal/mol without Na 2 CO 3 to 2.44 kcal/mol with Na 2 CO 3 . Similarly, a reduction from 10.4 to 7.5 kcal/mol is observed for phenol. Also, Na 2 CO 3 plays a key role in reducing corrosion on the reactor walls by first neutralizing the acid and then providing a large surface area for adsorption of the precipitated corrosive compounds. Because Na 2 CO 3 is insoluble in supercritical water, it precipitates as fine particles with a large surface area. A new reactor design is proposed for obtaining fine Na 2 CO 3 particles based on the supercritical anti-solvent method; these fine particles provide a surface area that is several orders of magnitude larger than that of the reactor walls.
An Agile embedded systems capstone course

The objective of this paper is to present the outcomes of an embedded systems senior design capstone course offered for Computer Engineering Technology students. This course has being taught five times using the presented format. At every offering, slight modifications have been done in an attempt to improve the student's experience and engagement. The most important intended learning outcomes for this course are: to enable team collaboration, to learn project management techniques, to develop a product from idea to implementation, and to make a professional presentation of their work to an audience. The innovative practices included in this course are: use of Agile Project Management methodologies, no paper trail all information is in electronic form, emulation of an entrepreneurial experience.
Mechanisms of lithium action.

LITHIUM first attracted medical attention in the 19th century when A. B. Garrod attempted to treat gout with Li+ because Li+ urate was found to be more soluble than Na+ or K+ urate. However, the ub...
Some measurements of calcium oxalate nucleation and growth rates in urine-like liquors

Abstract Development of the MSMPR crystallizer for study of CaOx crystallization kinetics was traced from its beginning to current versions having in situ particle size measurements with on-line minicomputer data regression. MSMPR studies of COD crystallization kinetics in a synthetic urine liqour, with or without a component of human urine, were summarized. These results were extended by the data of this study which show the effects of osmolarity, Ox feed concentration, urea and magnesium as they effect COD nucleation and growth rates. Although consistent variations in COD crystallization kinetics were observed with the above variables, such variations (with the exception of Ox in feed) are small compared with effects due to urinary macromolecules.
Reconstitution of cAMP-dependent protein kinase regulated renal Na+-H+ exchanger.

Studies were performed to determine if the Na+−H+ exchanger, solubilized from renal brush border membranes from the rabbit and assayed in reconstituted artificial proteoliposomes, could be regulated by cAMP-dependent protein kinase. Octyl glucoside solubilized renal apical membrane proteins from the rabbit kidney were phosphorylated by incubation with ATP and highly purified catalytic subunit of cAMP-dependent kinase.22Na+ uptake was determined subsequently after reconstitution of the proteins into proteoliposomes. cAMP-dependent protein kinase resulted in sustained protein phosphorylation and a concentration-dependent decrease in the amiloride-sensitive component of pH gradient-stimulated sodium uptake. The inhibitory effect of cAMP-dependent protein kinase demonstrated an absolute requirement for ATP and was blocked by the specific protein inhibitor of this kinase. cAMP-dependent protein kinase also inhibited22Na+ uptake in the absence of a pH gradient (pHin 6.0. pHout 6.0) and the inhibitory effect was blocked by the specific inhibitor of the kinase. Solubilized membrane proteins exhibited little endogenous protein kinase or protein phosphatase activity.
Contraceptive steroid treatment affects steroid binding proteins and the percentage of free 17β-estradiol and testosterone in the cynomolgus monkey (itmacaca fascicularis)

The levels of steroid binding globulins were characterized in cynomolgus monkeys that were treated with contraceptive steroid preparations delivered either by intravaginal rings (CVR) or orally (OC) in the diet. Levonorgestrel (dNG) was the bioactive progestin and the estrogen was either 17β-estradiol (E2) in the CVR treatment or ethinyl estradiol (EE) in the OC treatment. Both contraceptive treatments lowered sex hormone binding globulin (SHBG) levels below those observed in males (P < 0.05) and normal females (P < 0.01). Corticosteroid binding globulin (CBG) was elevated (P < 0.01) in the OC treatment, demonstrating the potency of EE. The distribution of E2 and testosterone (T) between binding to SHBG or albumin and the unbound fraction was calculated after the determination of the percentage of free steroid by centrifugal ultrafiltration. Both contraceptive treatments increased the percentage of free T and E2 (P < 0.01) in the subset of monkeys that were evaluated, but the percentage bound to SHBG and albumin were different only for the CVR group (P < 0.05). Decreased total T concentrations in the treatment groups offset any increase in free T concentrations associated with an increase in the percentage of free T. The differences in the distribution of binding to SHBG associated with these contraceptive steroid treatments was influenced more by the reduction in the binding capacity of SHBG than by the displacement of E2 and T from SHBG by dNG.
Yield of venom obtained from Crotalus atrox by electrical stimulation

Abstract Venom was collected from 150 freshly caught specimens of Crotalus atrox . Quantity and quality of venom produced were studied as a function of length of time in captivity, feeding, size of the snake and frequency of venom extraction by electrical stimulation of the mandibulae compressor glandulae muscles. The volume of venom collected from Crotalus atrox and other venomous snakes was increased by electrical venom extraction (EVE) without altering the quality of the venom or injuring the snake. The first EVE on freshly caught snakes yielded relatively low and highly variable volumes. Fasted snakes produced more venom at a faster rate than force-fed snakes. EVE of rested and fasted snakes was found to be an excellent way to obtain large amounts of venom for research.
Physician evaluation of obesity in health surveys: “who are you calling fat?”

Previous research on status generalization suggests that physicians may use non-medical factors in their evaluation, interpretation, and treatment of persons presenting for care. This study compares physicians’ evaluations of obesity with physical measurements of body stature and fat collected from a large national health examination survey. While the anthropometric measures are strong predictors of physician evaluations of obesity, between 13% and 19% of the respondents were classified in ways that could not be predicted from the anthropometric measures. Moreover, personal and status characteristics were related to physicians’ evaluations of obesity. Women, especially White and taller women, were more likely to be evaluated as obese than would be predicted from the anthropometric measures—African American women were less likely than their White counterparts to be so classified. Physicians’ evaluation of obesity was least consistent with measured obesity for older respondents. Indeed among men, age was the most important status characteristic shaping physician evaluations: older men were more likely to be evaluated as obese. The findings suggest that the cluster of status characteristics is important to physicians during medical evaluations.
32 REFLEX MODIFICATION BY ACOUSTIC AND TACTILE SIGNALS IN NEONATES

In recent efforts directed to the analysis of sensory processing in the newborn, neonates and adults were exposed to various reflex modification procedures. Previous work with adults had indicated that when a tone precedes a reflex eliciting stimulus by an appropriate interval the amplitude of the reflex is inhibited. If the tone is presented simultaneously with the reflex-eliciting event, response to amplitude is augmented. The eye-blink eliciting device consisted of a miniature solenoid with a teflon striker which could deliver a controlled tap; a miniature photo reflective densiometer attached to a TDH 39 earphone assessed the eye blinks. For each experiment, 15 healthy term appropriate-for-gestational-age infants were studied between 13 to 90 hrs of age during quiet sleep; 15 adults were studied for comparison. Four experiments employing identical reflex modification procedures on neonates and adults suggest a developmental difference in processing sensory stimuli. Neonates failed to exhibit reflex inhibition by either prior tactile or acoustic stimuli (either tone pulses or sustained tones). Adults exhibited robust reflex inhibition to these same stimuli. Neonates, however, exhibited reflex augmentation when mild tones (70 dB) were presented simultaneously with a tap, while for adults tones of at least 90 dB were necessary to obtain reliable reflex augmentation. The present findings in conjuction with those of others suggest that neonates fail to exhibit inhibition because the neural system responsible for this effect are not fully developed at birth.
Induced Meiotic Gynogenesis of Paddlefish Polyodon spathula

Viable, diploid gynogenetic (gynogenotes) paddlefish Polyodon spathula were produced by activating eggs with ultraviolet-irradiated shovelnose sturgeon Scaphirhynchus platorynchus spermatozoa and heat shocking. Without irradiation treatment, sturgeon spermatozoa appeared to activate the eggs (up to gastrulation), but did not result in any viable hybrids. Experiment 1 determined that heat-shock treatment of 35 C for a 2-min duration within the interval of 2–22 min post-activation resulted in highest yield of gynogenotes (12–19%) from eggs incubated at 18 C. Experiment 2 applied the heat shock treatment at 35 C from 14.0 to 28.0 min in 2-min intervals after activation at 18 C for a larger scale of gynogenetic production. Both experiments showed that the best yields of gynogenotes were obtained when the heat shock treatment occurred at 16, 18, and 20 min after activation. When these times were expressed in terms of τ0. units (duration of one mitotic cycle of synchronous cell division related to water temperatures), optimal activations were 0.26, 0.29, and 0.32τ0 (τ0@ 18 C = 63.5 min). Experiment 3 tested the utility of τ0. at two different pre-shock incubation water temperatures of 18 C and 16 C, and determined that there was no significant interaction in percentage of viable gynogenotes between two different incubation temperatures and the mitotic intervals (0.21, 0.26, 0.31, 0.36, 0.41τ0) tested. Best survival of gynogenotes occurred when eggs held at either pre-shock incubation water temperatures were shocked at 0.26τ0 All gynogenotes examined were histologically confirmed to have ovarian tissue and were determined to have similar oocyte development to that of normal female (control) paddlefish.
Loss and reacquisition of hippocampal synapses after selective destruction of CA3–CA4 afferents with kainic acid

Abstract Intraventricular injections of kainic acid were used to destroy the hippocampal CA3–CA4 cells bilaterally in rats, thus denervating the inner third of the molecular layer of the fascia dentata and stratum radiatum of area CA1. Electron microscopic studies showed that this lesion reduced the synaptic density of the CA1 stratum radiatum by an average of 86%. The synaptic density of the inner third of the dorsal dentate molecular layer declined by two-thirds and the corresponding zone of the ventral dentate molecular layer by about half. Within 6–8 weeks the synaptic density of these laminae had been restored to the control value or nearly so. In the CA1 stratum radiatum about 72% of the synaptic contacts destroyed by the lesion were replaced, the inner third of the ventral dentate molecular layer recovered 75% of its lost synapses and the inner third of the dorsal dentate molecular layer apparently recovered virtually all of them. The newly formed synapses did not differ noticeably from those normally present. A kainic acid lesion reduced the synaptic density of the outer two-thirds of the dentate molecular layer by 30% within 3–5 days, despite a virtual absence of presynaptic degeneration in that zone. This result implies a substantial disconnection of perforant path synapses. It did not appear to depend on the extent of denervation of the inner zone. The loss of perforant path synapses was completely reversible. We suggest that the dentate granule cells shed a portion of their synapses in response to a substantial loss of neurons to which they project and regained them when their axons had formed new synaptic connections.
Alzheimer's disease: Aβ, tau and synaptic dysfunction

Alzheimer's disease is a progressive neurodegenerative disorder that is characterized by two hallmark lesions: extracellular amyloid plaques and neurofibrillary tangles. The role that these lesions have in the pathogenesis of AD has proven difficult to unravel, in part because of unanticipated challenges of reproducing both pathologic hallmarks in transgenic mice. Recent advances in recapitulating both plaques and tangles in the brains of transgenic mice are leading to novel insights into their role in the degenerative process, including their impact on synaptic activity and plasticity. Transgenic mice that harbor both neuropathological lesions are also facilitating the elucidation of the relationship of these proteinaceous aggregates to one another and providing a crucial in vivo system for developing and evaluating therapies.
Separation and Characterization of Two Phosphorylase Phosphatase Inhibitors from Rabbit Skeletal Muscle

Two heat-stable and trypsin-labile inhibitors of phosphorylase phosphatase, designated inhibitor-1 and inhibitor-2, were partially purified from extracts of rabbit skeletal muscle by heating and coloumn chromatography using DEAE-dellulose and Bio-gel P-60. Inhibitor-1 exists in an active phosphorylated form and an inactive dephosphorylated form. The interconversion of phosphorylated inhibitor-1 and dephosphorylated inhibitor-1 is mediated by protein kinase dependent on adenosine 3':5'-monophosphate (cyclic AMP) and a Mn2+-stimulated phosphoprotein phosphatase. Inhibitory activity of inhibitor-2 is not influenced by treatment with either the kinase or the Mn2+-stimulated phosphatase. The molecular weights of inhibitor-1 and inhibitor-2 estimated by sodium dodecylsulfate-polyacrylamide gel electrophoresis are 26000 and 33000 respectively. Both inhibitor-1 and inhibitor-2 inhibit phosphorylase phosphatase by a mechanism which appears to be non-competitive with respect to the substrate phosphorylase a. Inhibitor fractions at early stages of purification also inhibit cyclic-AMP-dependent histone phosphorylation, but this kinase inhibitory activity resides with a protein moiety which is separable from inhibitor-1 and inhibitor-2.
Parks as a Tool for HIV Management

Access to parks improves overall health outcomes in the general population. Given that HIV infection has become a chronic disease to manage, among populations engaged in medical care, parks may be promoted as physical activity opportunities in order to manage chronic comorbid conditions. We conducted a cross-sectional examination of the relationships between sociodemographic and biomedical characteristics to park proximity among 635 individuals receiving outpatient HIV care. The data collected included HIV-related biomarkers, depression, and diagnoses of other chronic diseases. The total acres of parks an individual is exposed within one-quarter mile from their home were assessed. The cohort included 635 individuals (67% men, 73% black, and 21% white, mean age 42 years). Unemployment was negatively associated with park availability. Park proximity was not associated with depression or HIV biomarkers. As yet, little effort has been committed to promoting park usage as a low-cost, sustainable method to addressing comorbidities among individuals with HIV.
Response of guinea pig smooth and striated urethral sphincter to cromakalim, prazosin, nifedipine, nitroprusside, and electrical stimulation

Prazosin (an alpha-1-adrenergic blocker) and cromakalim (potassium channel opener), given alone, induced significant fatigue of the urethral sphincter at a concentration of 10(-4) M; both drugs combined achieved a significant sphincteric fatigue at a concentration of 10(-5) M each. To 10(-4) M hexamethonium (ganglionic smooth muscle blocker) and 10(-4) M decamethonium (nicotinic blocker of striated muscle) the striated urethral sphincter responded like striated muscle with no detectable function of its smooth muscle component. Therefore, the striated component seems to play a dominant role in sphincteric function. With calcium depletion or in the presence of a calcium channel blocker (10(-4) M nifedipine) the urethral sphincter showed a relative enhancement of response to electrical field stimulation when compared with smooth and skeletal muscle, whose responses were both significantly reduced. This phenomenon could not be explained with calcium-dependent, inhibitory, nitric oxide-releasing nerves, as the NO-synthase blocker N-nitro-L-arginine (10(-5) M to 5 x 10(-5) M) failed to induce the enhancement of sphincter contraction during electrostimulation found with calcium depletion. Still, NO-releasing nerves might play a role in sphincteric relaxation because sodium nitroprusside (10(-5) M) induced a significant relaxation of the urethral sphincter precontracted with 80 mM potassium. The potential to weaken sphincteric closure with drugs, exemplified by the results obtained in response to prazosin and cromakalim, would represent a therapeutic advance in the patient with neurogenic bladder dysfunction.
Dryland corn response to tillage and nitrogen fertilization. I. Growth‐yield‐N relationships

Abstract Crop response to fertilizer nitrogen (N) is dependent upon tillage management. This study was conducted to determine how tillage rotation influences non‐irrigated crop growth, N uptake and yield. The effects of tillage rotation, N rate and N timing schedule on early season dry matter production and N uptake, ear leaf N concentration at silking, and yield of corn [Zea mays (L.) Pioneer 3378] were investigated at Painter, VA, on an Altavista loam (fine‐loamy, mixed, thermic Aquic Hapludult). In 1986, maximum yields achieved in the 6‐year continuous no till (NT) [5.82 Mg/ha] and first year no till (AT) [5.64 Mg/ha] were significantly greater than that of the 6‐year continuous conventional till (CT) [3.67 Mg/ha], but no yield differences were obtained in the drier 1987 season. A higher rate of N fertilizer was required to obtain maximum yield in the first year no till (168 kg N/ha) than in the NT (112 kg N/ha) during 1986. Early 1986 N uptake and growth response with and without N at planting increas...
Sources of difficulty in understanding newtonian dynamics

A series of force and motion problems was presented to 40 high school science students. The results revealed that the majority of the students only partially understood the formalisms of Newtonian physics. Many had difficulty determining the effect that a force would have on an object's speed of motion and many neglected to take into account the current speed of motion when attempting to predict how a force would alter an object's direction of motion. The students' justifications for their erroneous answers suggest that they utilize diverse, and often inconsistent, ideas when solving force and motion problems. These include (a) faulty beliefs about force and motion which have been derived from living in a world where unseen frictional forces operate; (b) partially understood examples from physics class; and (c) knowledge of the properties of scalar arithmetic, some of which do not transfer to vector arithmetic. The students thus employ components of their knowledge, which seem relevant to the solution of force and motion problems, but which often have properties that conflict with the implications of Newton's laws of motion.
Effects of group I cations on the gelation of iota carrageenan

Abstract N.m.r. and rheological measurements have been used to study the gelation of iota carrageenan. Gelation has been found to occur only at polymer concentrations above the critical entanglement concentration. The high temperature sol state above the gel-sol transition appears to be an entangled polymer network. Although Li+ and Na+ ions are less effective at gelling the polymer than K+, Rb+ and Cs+ all cationic forms studied gel at sufficiently high polymer concentration and ionic strength. 7Li+, 23Na, 39K, 87Rb and 133Cs n.m.r. studies have been made as a function of temperature. The lithium salt form (2.2% w/w concentration) formed a viscoelastic solution at room temperature. The other salt forms gelled on cooling. The spectra of Li, Na and Cs carrageenan showed little change on heating whereas K and Rb spectra showed marked changes in apparent intensity. The nature of the cation interaction with the juntion zones is discussed.
How d = 3 QCD resembles d = 4 QCD

Abstract With a view to understanding the non-perturbative behavior of both theories, we discuss (in a gauge-invariant way) the dynamical similarities between (parity-conserving, quarkless) d = 3 QCD and d = 4 QCD. Both theories have gauge-invariant running charges with perturbative ghosts and one-loop-unstable vacua leading to gluon condensation. Non-perturbative extensions of these phenomena lead to spontaneous gluon mass generation, area-law confinement, and non-classical solitons.
Two precursors of melanin-concentrating hormone: DNA sequence analysis and in situ immunochemical localization.

Abstract Two precursors to Chinook salmon (Oncorhynchus tshawytscha) melanin-concentrating hormone, an important factor in teleosts involved in the control of skin pigmentation and stress responsiveness, have been identified from DNA sequence analysis. Both precursors encode proteins of 132 amino acids and they share 107/132 amino acid identities. The biologically active 17-residue peptide is located at the C terminus of both precursors and can be liberated by proteolytic cleavage following two adjacent arginine residues. Additional putative proteolytic processing sites are located within the two precursors. Northern analysis demonstrated an intense hybridization signal of 750 nucleotides in the hypothalamus. Immunocytochemical studies as well as in situ hybridization analyses identify intensely staining cell bodies in the hypothalamus in the area of the lateral tuberal nucleus.
Clinical Differentiation with the Spiral Aftereffect Technique

The spiral aftereffect (SAE) apparatus was administered to 100 Ss, 50 independently medically diagnosed organic patients and 50 normals matched in sex and age to the first group. Each S was given s...
Using artificial intelligence to model juvenile recidivism patterns

Abstract Risk management has had a major positive impact on increasing the effectiveness of probation supervision. However, while methods and procedures for designing and implementing such a system are well known, there is still a lack of utilization among many juvenile courts. Discriminant classification and neural network models were developed to decide the set of classification variables that would significantly differentiate recidivists from non-recidivists. These models correctly differentiated between recidivists and non-recidivists in 63 percent (discriminant) and 99 percent (neural network) of the cases respectively.
Phy Tunes: Phosphorylation Status and Phytochrome-Mediated Signaling

Phytochromes are photoreceptors that regulate various aspects of plant growth and development. In this issue of Cell, Ryu et al. (2005) show that PAPP5, a type 5 protein phosphatase, acts on a biologically active phytochrome, increasing its stability and affinity for a downstream signal transducer and thus enhancing plant photoresponses.
Various Facets of Rings Between D[X] and K[X]

Abstract Since the circulation, in 1974, of the first draft of “The construction D + XD S [X], J. Algebra 53 (1978), 423–439” a number of variations of this construction have appeared. Some of these are: The generalized D + M construction, the A + (X)B[X] construction, with X a single variable or a set of variables, and the D + I construction (with I not necessarily prime). These constructions have proved their worth not only in providing numerous examples and counter examples in commutative ring theory, but also in providing statements that often turn out to be forerunners of results on general pullbacks. The aim of this paper will be to discuss these constructions and the remarkable uses they have been put to. I will concentrate more on the A + XB[X] construction, its basic properties and examples arising from it.
Behavior of ceria-copper oxide sorbents under sulfation conditions

Simultaneous removal of SO2 and NOx using a regenerable solid sorbent will constitute an important improvement over the use of separate processes for the removal of these two pollutants from stack gases and possibly eliminate several shortcomings of the individual SO2 and NOx removal operations. Alumina-supported cerium oxide sorbents perform well at relatively high temperatures (823–900 K) as regenerable desulfurization sorbents. Addition of copper oxide to ceria lowers the sulfation temperature of ceria down to 773 K and sulfated ceria-based sorbents can function as selective SCR catalysts even at elevated temperatures. Sorbents containing cerium oxide and copper oxide supported on alumina were prepared by impregnation. Their sulfation performance was investigated in a TGA setup, studying mainly the effects of temperature and sorbent composition. It was found that in the 723–823 K temperature range combined cerium oxide–copper oxide sorbents had specific sorbent capacities (mass of sulfur removed per unit mass of metal sorbent) and sulfation rates significantly larger than those of cerium oxide or copper oxide sorbents used alone. Best sulfation performance was shown by the sorbent containing 1 : 1 molar ratio of cerium and copper. Specific sulfur capacities decreased as the coverage of the support surface by the metal oxides approached mono-layer coverage. At 823 K, specific sulfur capacities more than 20% over the theoretical value were obtained by sorbents with Ce/Cu molar ratios over one. This was attributed to the bulk sulfation of the alumina support.
Implementation of a robust SQP algorithm

This paper presents an implementation of a sequential quadratic programming (SQP) algorithm for the solution of nonlinear programming (NLP) problems. In the proposed algorithm, a solution to the NLP problem is found by minimizing the L1 exact penalty function. The search direction for the penalty function minimization is determined by solving a strictly convex quadratic programming (QP) problem. Here, we make the basic SQP algorithm more robust (i) by solving a relaxed, strictly convex, QP problem in cases where the constraints are inconsistent, (ii) by performing a non-monotone line search to improve efficiency, and (iii) by using second-order corrections to avoid the Maratos effect. The robustness of the algorithm is demonstrated via a C language implementation that is applied to numerous parameter optimization and optimal control problems that have appeared in the literature. The results obtained show that both non-monotone line searches and second-order corrections can significantly reduce the amount of work required to solve parameter optimization problems.
Popular Culture in the Making of Anti-Imperialist and Nationalist Sentiments in Sichuan

Existing Western scholarship on the rights recovery movement in Sichuan mainly focuses on the role played by elites. This article argues that popular culture, in the form of folk stories, songs, and children’s primers, also contributed to that movement by shaping and expressing popular anti-imperialist attitudes. Its analysis of primers available in late Qing Sichuan and popular stories about the activities of foreigners prevalent in the early 1900s serves to reveal a rich local cultural milieu of time-nurtured anti-imperialist sentiment among common people, which broadly influenced local political action. The protests over the Jiangbei mining concession encompassed both elite and ordinary people, although each group understood the issue differently.
Guidelines for splinting implants.

Abstract Statement of Problem: Teeth and implants have different mobility patterns. Thus, it has been believed that implant-supported restorations should not be connected to natural teeth. However, this is not always the case. Purpose: This article presents guidelines for connection of restorative components when implant abutments and natural teeth are involved. Methods: Methods of connection are discussed. Conclusion: This article presents options for splinting of prosthetic components. (J Prosthet Dent 2000;84:210-4.)
Criterion for the Detachment of Laminar and Turbulent Boundary Layers

A criterion is proposed for the detachment of incompressible, steady, two-dimensional boundary layers under the influence of adverse pressure gradients on smooth, faired surfaces, in the absence of heat or mass transfer. It is proposed that detachment will occur if a suitably defined dimensionless parameter measuring the ratio of the boundary-layer momentum defect to the freestream momentum reaches a maximum value. The approach requires knowledge of the relations between integral thicknesses during separation, but no empirically determined critical value is required for any boundary-layer shape factor. Consensus values of such parameters follow accurately from the proposed procedure. The criterion is exact in the context of the Karman-Pohlhausen theory and precisely satisfied by numerically evaluated solutions of the Falkner-Skan equation. The criterion is consistent with Simpson's experimental data and compares well with several established semi-empirical methods for predicting the intermittent transitory detachment of turbulent boundary layers.
Role of Gulf Stream frontal eddies in forming phytoplankton patches on the outer southeastern shelf1

Continuous surface mapping of temperature, salinity, and chlorophyll along a 300-km segment of the Gulf Stream cyclonic front defined the spatial scales of a large diatom patch that persisted throughout a 10-day study. The patch was localized in the upwelled cold core of a Gulf Stream frontal eddy centered over the 200-m isobath off Jacksonville, Florida, in April 1979. The 2 ..mu..g.liter/sup -1/ surface chlorophyll isopleth enclosed in area >1,000 km/sup 2/ with an alongshore dimension of 130 km. Surface chlorophyll exceeded 5 ..mu..g.liter/sup -1/ within the upwelled cold core of the eddy, 10-100x higher than concentrations in Gulf Stream or resident shelf surface water. Diatoms dominated the patch with the maximum observed abundance >10/sup 6/ cells.liter/sup -1/. Several days after the initial shipboard mapping, the size, location, and strong chlorophyll gradients of the patch were confirmed with a surface chlorophyll image generated from an ocean color scanner (OCS) flown aboard a NASA U-2 aircraft. We show that the upwelling associated with eddies forming along the Gulf Stream cyclonic front results in localized zones of high near-surface production and plant biomass that lie adjacent to oligotrophic surface waters of the Gulf Stream.
Tissue levels of haloperidol by radioreceptor assay and behavioral effects of haloperidol in the rat.

Abstract A radioreceptor assay verified by independent biochemical methods was used to evaluate tissue levels of neuroleptic activity in serum and brain extracts after injections of haloperidol in the rat. The assay detected activity between doses of 0.1 and 10 mg/kg at times between 0.25 and 12 hrs. Tissue levels in blood and brain were highly correlated and corresponded well with a behavioral test of catalepsy at one hour after drug administration. This relationship between brain levels and behavior persisted but changed quantitatively over time.
Modeling the progression of articular erosion in rheumatoid arthritis (RA): Initial mathematical models

Rheumatoid Arthritis (RA) is a chronic inflammatory disease of unknown cause that affects around 1% of the adult population in the U.S. Women are more often affected than men by a ratio of 3 to 1, and although the disease can appear at any age in adult life, the incidence and prevalence increase with age. The inflammatory process that characterizes RA, centers in and around articular structures and is characterized by destruction that progresses over time. Attempts to apply curve fitting to the analysis of the progression of radiographie damage in RA have lead to numerous forms of mathematical models (linear, quadratic, cubic, square root, first-order kinetics, etc.). None of these models has been very successful in that a signficiant degree of ambiguity of the appropriate model form still remains. A mathematical model of the progression of RA would be useful to evaluate the effect of interventions to ameliorate joint destruction. In this paper, we present a rigorously derived second-order kinetics model and propose 1.(a) a possible explanation for the ambiguity found in prior analyses, and 2.(b) present a potentially clinically useful model for RA disease progression based upon radiographic assessment of joint damage.