cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal closed-loop control of the azimuthal velocity profile by E×B actuation in HELCAT

The cross-field turbulence-driven particle transport in magnetically confined plasmas can be reduced by adequately shaping the flow profiles. HELCAT (HELicon-CAThode), a linear magnetized plasma device, uses concentric ring electrodes to modify the flow profiles by E×B actuation. As a result, turbulent particle and heat transport can be mitigated by generating a sheared radial electric field through the varying ring voltages. Active control of the turbulent fluctuations, including the associated cross-field particle transport, via manipulation of flow profiles is investigated in this work. Once a desired radial azimuthal velocity profile, and its associated level of turbulent fluctuations, are identified, the challenge of systematically achieving and sustaining it still remains. A model-based feedback controller is proposed to achieve this goal even in the presence of external disturbances, model uncertainties and perturbed initial conditions. A linear-quadratic-integral (LQI) optimal controller is designed to minimize a weighted combination of the tracking error and the control effort. Numerical simulations show the effectiveness of the proposed controller to regulate the radial azimuthal velocity profile around a prescribed desired profile. The proposed control solution has the potential of being used as a systematic tool to elucidate the physics of laboratory plasmas such as those achieved in HELCAT.
The Haemodynamic Effects of Correction of Anaemia in Haemodialysis Patients Using Recombinant Human Erythropoietin

STUDY OBJECTIVE To evaluate the acute and long-term haemodynamic response to recombinant human erythropoietin (rHuEpo) correction of chronic anaemia in haemodialysis-supported patients. DESIGN Prospective analysis of randomly chosen patients undergoing the multicentre phase III clinical recombinant erythropoietin trial. SETTING Chronic haemodialysis patients supported in one of two dialysis centres of a large urban tertiary referral centre. PATIENTS Thirteen of the 59 patients who met the criterion for participation in the multicentre clinical phase III trial of recombinant erythropoietin were randomly chosen. Mean age (42.6 years), and time on dialysis (3.4 years) was representative of the study population. Ten patients were receiving antihypertensive therapy, which remained unchanged throughout the study. INTERVENTIONS Haemodynamic testing was done in a fasting state, in the supine position, utilising radionuclide angiocardiography. Plasma volume was determined by 125I-labelled serum albumin. Echocardiographic and hormonal evaluations were also performed at each haemodynamic evaluation. All testing was done immediately prior to first dose of drug, upon reaching target haematocrit, and at 6 months and 1 year of continued non-anaemia. MEASUREMENTS AND MAIN RESULTS Mean arterial pressure did not seem to change at any of the study periods, while total peripheral resistance did drop at target (34 +/- 2.5 vs 27.2 +/- 3.2 microns2, P = 0.05). Cardiac output (5.6 +/- 0.5 vs 7.6 +/- 0.8 l/min, P = 0.005) and stroke volume (77 +/- 9.6 vs 116 +/- 15.4 ml, P = 0.005) also rose at this same period but returned to baseline during later periods. Ejection fraction increased over baseline at both target and 1 year study points (50 +/- 2.7 vs 57.7 +/- 3 vs 63 +/- 4.3, P = 0.05) while the haematocrit was increased at target (21.8 +/- 0.9 vs 35.6 +/- 1.0, P less than 0.0005), and maintained at this new level throughout the study. Total blood volume (118 +/- 6.7 vs 100.4 +/- 8.1 ml/cm, P less than 0.05) and plasma volume (150 +/- 8.2 vs 108.5 +/- 9.4 ml/cm, P less than 0.001) decreased at 1 year. CONCLUSION Recombinant human erythropoietin is effective in correcting the anaemia of chronic renal failure. Any haemodynamic changes which may be induced seem to occur early in the course of therapy, are different from those changes induced by blood transfusions, and tend to return to baseline with continued treatment.
CONFORMATIONAL STUDIES OF WHEAT GLUTEN, GLUTENIN, AND GLIADIN IN UREA SOLUTIONS AT VARIOUS PH'S.

Abstract Viscosity, sedimentation velocity, ultraviolet difference spectra, and optical rotatory dispersion measurements were carried out on wheat gluten, glutenin, and gliadin in 3 M urea plus 0.11 M KCl plus 0.02 M buffer at pH 3–10 at 25 °C or room temperature. An increase in intrinsic viscosity and a decrease in sedimentation coefficient for glutenin at pH 10 compared with that at pH 4 are consistent with an increase in asymmetry of the protein molecule. Parameters from optical rotatory dispersion studies on glutenin also indicate a conformational change at pH 10. Some increases in intrinsic viscosity were also observed for gluten and gliadin at pH 10, but the increase for gliadin might not be significant. The absence of tyrosine and tryptophan peaks in the ultraviolet difference spectra of gluten, glutenin, and gliadin suggests that these two amino acids are not involved in any interaction with other groups.
Obesity and receipt of personal care assistance for people with mobility impairments.

Objective: The purpose of this study was to evaluate the extent to which level of obesity was associated with hours of personal care among people with mobility impairments. Research Methods and Procedures: The analytic sample consisted of 9496 respondents to the Adult Disability Follow-Back Survey (NHIS-D Phase II) who had mobility difficulty and difficulty with at least one activity of daily living or instrumental activity of daily living. Logistic regression analyses determined the relationship between level of obesity and receipt of any paid or unpaid help, controlling for potential confounders. In addition, differences in hours of help by level of obesity were evaluated using multiple regression. Results: In the crude analysis, obese respondents were significantly less likely to receive any paid help than normal weight respondents (average odds ratio 0.75) and received significantly fewer hours of both paid and unpaid help. The difference in prevalence of receipt of any unpaid and any paid help by level of obesity was explained by adjustment for age and other demographic characteristics. Adjusted hours of paid and unpaid help were equivalent for those with and without obesity. Discussion: Obese people with mobility impairments received less help with personal care than those of normal weight, although these findings are explained by demographics. Nevertheless, these findings raise public health concerns given the growing obesity epidemic in the United States and lack of available resources to support younger persons with disabilities.
Seasonal changes in the metabolic properties of muscle in blue-winged teal, Anas discors

Abstract The gizzard, flight, and leg muscles of blue-winged teal undergo changes in their aerobic and anaerobic metabolic capacities during the flightless (molting) period and just as the birds begin to regain the capability of flight. These changes do not appear to be solely the result of a use/disuse phenomenon. The aerobic capacity of the flight muscles decreases with the onset of flightlessness but increases dramatically just prior to regaining flight with little or no physical conditioning. Furthermore, the increase in the aerobic and anaerobic capacity of the leg muscles during the flightless period fails to totally mimic the changes known to occur with increased aerobic or anaerobic muscle use. The muscles of blue-winged teal appear to prepare, by some mechanism(s) as yet not elucidated, for their changed role at the onset of migration and molt, rather than simply responding to current muscle use.
Evaluation of a solid stream radial nozzle on fixed-wing aircraft, for penetration of spray within a soybean canopy

Experiments were conducted to evaluate the Accu-Flo multiple orifice nozzle for penetration of spray into a soybean (Gly- cine max L.) canopy by comparing results to those from a popular straight stream nozzle and rotary atomizer. A mixture of water + Induce® adjuvant was applied at three different spray release heights in a random sequence, using an Air Tractor 402-B agricultural aircraft. Sampler stands were placed at twenty-four locations in the field. Water sensitive paper (WSP) cards were clipped onto rigid stands just above the canopy and 30 cm off the ground within the canopy. Weather data were recorded using two different stations on-site. Wind was predominantly from the west and parallel to the direction of the spray runs. The spray delivery systems compared were the Accu-Flo nozzles, (64 needle 0.020 opening), CP®-09 straight stream with 5 degree deflection, and Micronair® AU5000 atom- isers (14 mesh screen) at a low volume spray rate of 18.7 l/ha. A total of 54 spray runs were made over three days, and heights were varied at 3.7 m, 4.9 m and 6.1 m. Water sensitive papers were scanned and analysed for coverage per unit card area using an image analysis system. Altitude and (Nozzle X Altitude) interaction were significant effects on coverage at the 0.01 and 0.07 significance levels, respectively, for the top cards. Nozzle type was not a significant effect on coverage for the top cards, but was significant at the 0.01 level for the bottom cards. Altitude alone had no obvious effect on coverage for the bottom cards, although it had an effect for the top cards. The highest percentage area of spray coverage was observed from the Accu-Flo nozzles, especially for the bottom cards. Average spray coverage from the Accu-Flo nozzles was 1.7 times higher than coverage from the CP® nozzles or Micronair® atomisers in the lower portion of the canopy.
The Impact of Isolation on Hospitality Employees' Job Satisfaction and Job Performance:

Typical hospitality employees are a gregarious lot, enjoying nightlife and after- shift partying. What happens, then, when college-age hospitality employees spend the summer at an isolated lodge where there are no television or radio stations, where the only methods of transportation in and out of the area are by one daily- scheduled flight or by unscheduled ferry boats, and where the only place to unwind is the lodge itself?This pilot study was completed during the summer of 1990 at Glacier Bay Lodge, located in southeast Alaska on the waters of Bartlett Cove in island-studded Glacier Bay. The bay is surrounded by the 15,000-foot high Fairweather Mountains and contains the largest accumulation of tidewater glaciers in the world. The nearest city of any size is Juneau, located 60 miles away. Supplies are shipped by barge with a three-week turnaround for purchasing.The purpose of the study was (1) to determine whether isolation would have a deleterious effect on employee performance, morale, and social adj...
Analyzing memory accesses in obfuscated x86 executables

Programmers obfuscate their code to defeat manual or automated analysis. Obfuscations are often used to hide malicious behavior. In particular, malicious programs employ obfuscations of stack-based instructions, such as call and return instructions, to prevent an analyzer from determining which system functions it calls. Instead of using these instructions directly, a combination of other instructions, such as PUSH and POP, are used to achieve the same semantics. This paper presents an abstract interpretation based analysis to detect obfuscation of stack instructions. The approach combines Reps and Balakrishnan's value set analysis (VSA) and Lakhotia and Kumar's Abstract Stack Graph, to create an analyzer that can track stack manipulations where the stack pointer may be saved and restored in memory or registers. The analysis technique may be used to determine obfuscated calls made by a program, an important first step in detecting malicious behavior.
EM-based multiuser detection in fast fading multipath environments

We address the problem of multiuser detection in fast fading multipath environments for DS-CDMA systems. In fast fading scenarios, temporal variations of the channel cause significant performance degradation even with the Rake receiver. We use a previously introduced time-frequency (TF) Rake receiver based on a canonical formulation of the channel and signals to simultaneously combat fading and multipath effects. This receiver uses the Doppler spread caused by rapid time-varying channel as another means of diversity. In dealing with multiaccess interference and as an attempt to avoid the prohibitive computational complexity of the optimum maximum-likelihood (ML) detector, we use the expectation maximization (EM) algorithm to derive an approximate ML detector. The new detector turns out to have an iterative structure very similar to the well-known multistage detector with some extra parameters. At the two extreme values of these parameters, the EM detector reduces to either one-shot TF Rake or generalized multistage detector. For the intermediate values of the parameters, it combines the two estimates to obtain a better decision for the bits of the users. Because of using the EM algorithm, this detector has better convergence properties than the multistage detector; the bit estimates always converge, and if an appropriate initial vector is used, they converge to the global maximizer of the likelihood function. As a result, the new detector provides significantly improved performance while maintaining the low complexity of the multistage detector. Our simulation results confirm the expected performance improvements compared to the base case of the TF Rake as well as the multistage detector used with the TF Rake.
Predictors of mortality in nontraumatic subdural hematoma.

Object Subdural hematoma (SDH) is a common diagnosis in neurosurgical and neurocritical practice. Comprehensive outcome data are lacking for nontraumatic SDH. The authors determined which factors are associated with in-hospital mortality in a large sample of patients with nontraumatic SDH. Methods Using the Nationwide Inpatient Sample, the authors selected adults who had been hospitalized in the US between 2007 and 2009 and in whom a primary diagnosis of nontraumatic SDH (ICD-9-CM code 432.1) had been made. Demographics, comorbidities, surgical treatment, and discharge outcomes were identified. Univariate and multivariate analyses were performed to identify predictors of in-hospital mortality. Results Among 14,093 patients with acute nontraumatic SDH, the mean age was 71.4 ± 14.8 (mean ± standard deviation). In addition, 22.2% of the patients were admitted during the weekend. Surgical evacuation was performed in 51.4% of the patients, and 11.8% of all patients died during hospitalization. In multivariate ...
Granitic ring complexes and Precambrian hot-spot activity in the St. Francois terrane, Midcontinent region, United States

Surface and subsurface geologic data have led to the recognition of granitic ring complexes in the 1.5-b.y.-old St. Francois terrane of southeastern Missouri. The distinctive rock association of the ring complexes comprises alkaline silicic rocks with minor quartz monzonite, trachyte, and basalt. Three periods of granite emplacement are recognized: sub-volcanic granite massifs were emplaced below comagmatic rhyolites and ash-flow tuffs, quartz monzonite and associated hypabyssal rocks were intruded along ring fractures in cauldron-subsidence structures, and central plutons were emplaced in resurgent cauldrons. Similar magmatic complexes in the buried Precambrian basement of the Midcontinent indicate a period of widespread anorogenic magmatism that may have been induced by intraplate hot-spot activity. The post-Precambrian geologic record of the region suggests that recurrent, but localized and less intense, hot-spot activity was responsible for emplacements of alkaline ultramafic rocks, for tectonic adjustments, and for increased geothermal gradients that created favorable ore-concentrating environments in the sedimentary rocks.
Evaluation of Functional Ankle Dorsiflexion Using Subtalar Neutral Position A Clinical Report

This article presents the use of a specific technique when measuring ankle joint dorsiflexion for the purpose of determining the presence or absence of sufficient motion for ambulation. The importance of locating and maintaining the subtalar joint in the neutral position when applying either measuring or stretching techniques is emphasized. A brief discussion of selected compensatory mechanisms is presented to alert clinicians to symptoms that occur in the lower extremity and that may result from insufficient ankle dorsiflexion.
Reversal of Paralysis and Reduced Inflammation from Peripheral Administration of β-Amyloid in TH1 and TH17 Versions of Experimental Autoimmune Encephalomyelitis

β-Amyloid 42 (Aβ42) and β-amyloid 40 (Aβ40), major components of senile plaque deposits in Alzheimer's disease, are considered neurotoxic and proinflammatory. In multiple sclerosis, Aβ42 is up-regulated in brain lesions and damaged axons. We found, unexpectedly, that treatment with either Aβ42 or Aβ40 peptides reduced motor paralysis and brain inflammation in four different models of experimental autoimmune encephalomyelitis (EAE) with attenuation of motor paralysis, reduction of inflammatory lesions in the central nervous system (CNS), and suppression of lymphocyte activation. Aβ42 and Aβ40 treatments were effective in reducing ongoing paralysis induced with adoptive transfer of either autoreactive T helper 1 (T(H)1) or T(H)17 cells. High-dimensional 14-parameter flow cytometry of peripheral immune cell populations after in vivo Aβ42 and Aβ40 treatment revealed substantial modulations in the percentage of lymphoid and myeloid subsets during EAE. Major proinflammatory cytokines and chemokines were reduced in the blood after Aβ peptide treatment. Protection conferred by Aβ treatment did not require its delivery to the brain: Adoptive transfer with lymphocytes from donors treated with Aβ42 attenuated EAE in wild-type recipient mice, and Aβ deposition in the brain was not detected in treated EAE mice by immunohistochemical analysis. In contrast to the improvement in EAE with Aβ treatment, EAE was worse in mice with genetic deletion of the amyloid precursor protein. Therefore, in the absence of Aβ, there is exacerbated clinical EAE disease progression. Because Aβ42 and Aβ40 ameliorate experimental autoimmune inflammation targeting the CNS, we might now consider its potential anti-inflammatory role in other neuropathological conditions.
Differential effects of SCH 23390 on immobility behaviors in developing rats

The effects of a single injection of a dopamine D1 antagonist, SCH 23390, at doses of 0, 0.05, 0.1, and 0.2 mg/kg on three different kinds of immobility behavior were tested in rats of 10, 15, 20, and 30 days of age. Each animal was tested for the dorsal immobility response (DIR), vertical cling catalepsy, and bar catalepsy. A different pattern of results was found for each of the three immobility behaviors. SCH 23390 significantly increased the DIR at each age except 15 days; there was a progressive increase in effect from 10 to 20 to 30 days of age. At the lowest dose, drug-induced bar catalepsy peaked at 15 days of age and declined at 20 and 30 days of age. The effect of SCH 23390 on vertical cling catalepsy increased with age, plateauing at 20 days. Thus, the developmental pattern of immobility responses to this dopamine D1 antagonist differs with each behavior measured. © 1993 John Wiley & Sons, Inc.
Prevention of imbibitional injury in low vigor soybean embryonic axes by osmotic control of water uptake

Deterioration of soybean [Glycine max (L.) Merr. cv. Essex] seeds during accelerated aging at 41°C and 100% relative humidity predisposes the embryonic axis to injury during the initial period of imbibition. This injury was prevented or greatly reduced in severity when excised axes were imbibed on blotters containing 30% polyethylene glycol which slowed the rate of water uptake and when axes were pre-equilibrated to a high moisture level. Rates of water uptake by “high”(no treatment) and “low vigor”(accelerated aged) excised axes were identical. However, high vigor axes tolerated rapid water uptake during early imbition, whereas low vigor axes did not. Leakage of electrolytes during early imbibition was nearly six times greater in low than in high vigor axes. Polyethylene glycol significantly reduced the leakage of electrolytes from both low and high vigor axes. The data are in agreement with the hypothesis that seed deterioration in soybeans involves membrane changes which may predispose embryonic tissues to injury during imbibition. Reduction of the rate of water uptake during the initial period of imbibition would allow extra time for membrane repair or rearrangement, thus permitting the tissues to develop in a more orderly manner. The data indicate that deterioration in soybean seeds involves, at least in part, a decrease in ability of seed axes to tolerate rapid water uptake at the start of imbibition and that this weakness may be compensated by osmotic control of water uptake.
Middle‐Class Criminals? The Romance of the Ether and the City in Zambia

The Analysis of Fraud provides new insights into the workings of Third World Cities. Fraud is a middle class crime because it requires knowledge of how the urban ether, that complex of abstract systems and disembodied social relations, operates. While fraud is commonly criticized for undermining the social order, it is also romanticized. Three different cases drawn from Zambian newspapers form the basis for a discussion about the endemic nature of fraud, and the necessity of balancing state and organizational power against issues of personal freedom in the attempts to control fraud. [Crime, state power, personal freedom, Zambia]
Idiopathic optic perineuritis: Disguised as recurrent optic neuritis

A 53-year-old woman with history of mitral valve prolapse and astroesophageal reflux, presented to the Emergency Department ith right eye pain and blurry vision for 2 days. She had acute onset f retro-orbital pain and headache, eye pain with eye movement ut no nausea or vomiting. She also reported seeing gray spots and ad ‘blurry vision’ in the right eye. She reported that the temporal isual field was entirely gray in the right eye. She had no prior visual ymptoms and no family history of eye disease. She had no other eurological complaints. Her neurological examination showed extra ocular movements o be intact. She had a relative afferent pupillary defect in the right ye. On Humphrey 24-2 visual field, she had an enlarged blind spot nd constriction peripherally. On ophthalmoscopic examination he patient had disk swelling in the right eye (Fig. 1). There were no emorrhages or exudates. There was pain on eye movement. The emainder of her neurological and general physical examination as normal. Patient was admitted for evaluation of what was thought to be ptic neuritis. MRI brain with and without contrast did not reveal ny lesions suggestive of multiple sclerosis or other demyelinating isease. Lumbar puncture was normal. She was started on high dose
Screening with the exercise test: time for a guideline change?

This editorial refers to ‘Reasons for terminating an exercise test provide independent prognostic information: 2014 apparently healthy men followed for 26 years’† by J. Bodegard et al., on page 1394 Exercise testing as a screening modality must be considered in a new light given the paper by Bodegard et al. 1 and three other recent screening studies. First, this paper demonstrates the importance of using cardiac endpoints for evaluating cardiac tests. When adjusting for age, men who stopped exercising exclusively because of impaired breathing had a two-fold increased risk of dying from coronary heart disease (CHD) and a 3.5-fold increased risk of dying from pulmonary causes when compared with men who stopped due to volitional fatigue. Although all-cause mortality must be the primary endpoint of intervention studies, this is not the case for cardiac tests, where the goal is to determine which patients should be considered for a cardiac intervention to improve outcome. The authors demonstrated that certain responses predict pulmonary endpoints more so than cardiac. Secondly, this data set of 2014 asymptomatic Norwegians and two studies of asymptomatic Americans have clearly demonstrated the substantial risk ratios generated by the standard exercise test when combined with other risk factors. From the Cooper Clinic comes the largest screening study of the exercise test to predict CHD … *Corresponding author. E-mail address : vicmd{at}pacbell.net
High‐contrast, high‐sensitivity aqueous base‐developable polynorbornene dielectric

The impact of multifunctional epoxy-based additives on the crosslinking, photolithographic properties, and adhesion properties of a tetramethyl ammonium hydroxide developable, polynorbornene (PNB)-based dielectric was investigated. Three differ- ent multifunctional epoxy additives were investigated: di-functional, tri-functional, and tetra-functional epoxy compounds. The tetra- functional epoxy crosslinker enhanced the UV absorbing properties of the polymer at 365 nm wavelength. It was found that the epoxy photo-catalyst could be efficiently activated without a photosensitizer when the tetra-functional epoxy was used. The polymer mixture with additional (3 wt %) tetra-functional epoxy crosslinker and without a UV sensitizer showed improved sensitivity by a factor of 4.7 as compared to a polymer mixture containing the same number of equivalents of non-UV sensitive epoxy with a UV sensitizer. The contrast improved from 7.4 for the polymer mixture with non-UV absorbing epoxy and a UV sensitizer to 33.4 for the new for- mulation with 3 wt % tetra-functional epoxy and no UV sensitizer. The addition of the tetra-functional epoxy crosslinker also improved the polymer-to-substrate adhesion, which permitted longer development times, and allowed the fabrication of high-aspect- ratio structures. Hollow-core pillars were fabricated in 96-mm thick polymer films with a depth-to-width aspect-ratio of 14 : 1. The degree of crosslinking in the cured films was studied by nanoindentation and swelling measurements. V C 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 000: 000-000, 2012
The Performance of Five Different Metrics Against Pulsed Jamming

Metrics that are effective against white Gaussian noise are not necessarily effective against pulsed jamming that is optimized by an opponent. This paper analyzes and compares the information-bit error rates that result from using the hard-decision, maximum-likelihood, white-noise, automatic gain control, and erasure metrics against pulsed jamming. Practical implementation problems and limitations are identified and discussed.
Inhibition of cerebral vasoconstriction by dantrolene and nimodipine.

Cerebral vasoconstriction is associated with increased cytosolic Ca2+ concentration in vascular smooth muscle, presumably due to Ca2+ influx and Ca2+ release from intracellular stores. We tested the hypothesis that dantrolene (a blocker of Ca2+-induced Ca2+ release from the ryanodine receptor channel on the sarco-endoplasmic reticulum) would potentiate the action of nimodipine (a voltage-dependent L-type Ca2+ channel blocker, considered standard therapy for SAH) in inhibiting the vasoconstriction of isolated cerebral arteries. Sprague–Dawley rat basilar and femoral arteries were analyzed for ryanodine receptor expression by immunofluorescence and PCR. Vasoconstriction of basilar artery ex vivo was measured in a wire myograph while exposed to serotonin (5-HT) or endothelin-1 (ET-1) in the presence or absence of dantrolene (10–100 μM) and/or nimodipine (30 nM). Femoral artery was examined for comparison. Basilar and femoral arteries express only the ryanodine receptor 3 (RyR3) isoform. In both basilar and femoral arteries, dantrolene significantly inhibited the constriction to 5-HT, whereas it poorly affected the constriction to ET-1. The inhibitory effect of dantrolene on 5-HT was substantially increased by nimodipine, inducing a 10-fold increase in the 50% effective concentration of 5-HT and a 46% reduction in maximum basilar constriction. In femoral artery, dantrolene modestly affected constriction to phenylephrine and there was no interaction with nimodipine. Dantrolene has synergistic effects with nimodipine against 5-HT-induced vasoconstriction in isolated cerebral arteries. Dantrolene–nimodipine interaction will require testing in a pathophysiological model but might provide treatment for reducing SAH-related vasospasm or other 5-HT-related vasospastic syndromes, such as Call-Fleming syndrome.
Curriculum curtailment in prosthodontic education.

Abstract In summary, it appears that we are losing curriculum time in all but five of 46 American dental schools. We have not been able to surely determine a single or a common cause for this trend. Accordingly, we cannot presently reverse the disappointing trend, but as prosthodontic teachers, we can so behave that our co-workers will recognize our diligent efforts in teaching and, on that account, aid us in our plight. Last, we can and should declare publicly our frank and considered dissatisfaction with curriculum curtailment in prosthodontic education.
Seasonal shift in the foraging niche of a tropical avian resident: resource competition at work?

This study examined the foraging behaviour of a resident bird species, the rufous-capped warbler (RCWA, Basileuterus rufifrons), in a shaded-coffee farm in Chiapas, Mexico. Unlike many resident species that use shaded-coffee agroecosystems seasonally, RCWAs do not move to other habitats when migrants are present. RCWA foraging was compared when migrant birds were present (dry season) and absent (wet season). It was hypothesized that RCWAs would exhibit a seasonal foraging niche shift because of resource competition with migrants. Observations from both the canopy and coffee understorey show that RCWAs foraged almost equally in both vegetative layers during the wet season although they were more successful foraging in the canopy. In the dry season, migrants foraged primarily in the canopy and RCWAs shifted so that 80% of RCWA foraging manoeuvres were in the understorey. At that time RCWAs foraged less successfully in both vegetative layers. Avian predation in the dry season was found to reduce densities of arthropods by 47-79% in the canopy, as opposed to 4-5% in the understorey. In the canopy, availability of large (>5 mm in length) arthropods decreased by 58% from the wet to dry season. Such resource reductions could have caused the RCWA foraging niche shift yet other alternative or additional hypotheses are discussed. Shifts in foraging niche may be a widespread mechanism for some small insectivorous residents to avoid seasonal competition with abundant migrant species. Resumen: Este estudio examin´ o el comportamiento de forrajeo de un ave residente, Basileuterus rufifrons (RCWA), en una finca de caf´ e con sombra en Chiapas, MA diferencia de muchas aves residentes que usan los agroecosistemas de cafcon sombra solamante durante una estaci´ on, RCWAs no se van a otros h´
Lansoprazole: A Proton Pump Inhibitor

OBJECTIVE:To summarize the published data on lansoprazole, a proton pump inhibitor approved by the Food and Drug Administration for use in the treatment of duodenal ulcer, erosive esophagitis, and pathologic hypersecretory conditions (e.g., Zollinger-Ellison syndrome).DATA SOURCES:Published data on lansoprazole identified by MEDLINE searches (1985–1996), as well as other pertinent literature.STUDY SELECTION:Clinical efficacy trials discussed were limited to multicenter, double-blind, parallel group, prospective studies, where possible.DATA SYNTHESIS:Lansoprazole inhibits gastric acid secretion via inhibition of gastric hydrogen/potassium adenosine triphosphatase (H+,K+-ATPase), an enzyme of the gastric parietal cell membrane that forms part of the proton pump that performs the final step in the acid secretory process. Lansoprazole binds covalently to parietal cell H+,K+-ATPase, rendering it nonfunctional and inhibiting the secretion of gastric acid. In clinical trials, lansoprazole has been shown to be mo...
Global stability analysis and stabilization of a class-E/F amplifier with a distributed active transformer

Power amplifiers (PAs) often exhibit instabilities giving rise to frequency divisions or spurious oscillations. The prediction of these instabilities requires a large-signal stability analysis of the circuit. In this paper, oscillations, hysteresis, and chaotic solutions, experimentally encountered in a high-efficiency class-E/F/sub odd/ PA with four transistors combined using a distributed active transformer, are studied through the use of stability and bifurcation analysis tools. The tools have enabled an in-depth comprehension of the different phenomena, which have been observed in simulation with good agreement with experimental results. The study of the mechanism generating the instability has led to a simplified equivalent circuit from which the optimum stabilization network has been determined. The network enables a global stabilization of the circuit for all the expected operating values of the amplifier bias voltage and input power. This has been achieved with negligible degradation of the amplifier performance in terms of drain efficiency and output power. The stable behavior obtained in simulation has been experimentally confirmed.
Regulation of matrix metalloproteinase gene expression by a retinoid X receptor-specific ligand.

Objective To evaluate the effects of LG100268 (LG268), a synthetic ligand for the nuclear hormone receptor retinoid X receptor, on the expression of matrix metalloproteinase 1 (MMP-1) and MMP-13 induced by proinflammatory cytokines in a chondrocyte model. Methods SW-1353 human chondrosarcoma cells were used to study the effects of LG268 on interleukin-1β (IL-1β)–stimulated MMP production and collagen degradation. Gene expression was determined by quantitative real-time reverse transcription–polymerase chain reaction, and protein levels were determined by Western blot analysis. Collagen degradation was determined by an in vitro matrix destruction assay. The effects of LG268 on nuclear protein binding and histone acetylation were determined by electrophoretic mobility shift assay and chromatin immunoprecipitation assay, respectively. Results LG268 treatment specifically antagonized the IL-1β–mediated induction of MMP-1 and MMP-13 heterogeneous nuclear RNA, messenger RNA, and protein. The inhibitory effect of LG268 was found to be due to a decrease in the rate of MMP-1 and MMP-13 transcription. LG268 treatment also prevented the in vitro degradation of a type I collagen matrix by IL-1β–treated SW-1353 cells. The inhibitory effect of LG268 on MMP-1 and MMP-13 transcription appears to be mediated, at least in part, through modulation of histone modification in regions of the MMP-1 and MMP-13 promoters that contain binding sites for activator protein 1 transcription factors. Conclusion These data indicate that LG268 treatment selectively inhibits inflammatory cytokine–induced production of MMP-1 and MMP-13 at the level of gene transcription and blocks collagen destruction by proinflammatory cytokine–stimulated chondrocytic cells. This study is among the first to describe how rexinoids affect gene expression, and the findings suggest that the rexinoid class of compounds may have a future role in preventing the irreversible collagen destruction seen in the arthritides.
OxLDL induces macrophage γ-GCS-HS protein expression: a role for oxLDL-associated lipid hydroperoxide in GSH synthesis

Oxidized LDL (oxLDL) produced a rapid deple- tion of intracellular glutathione (GSH) followed by an adap- tive increase in J774 A.1 macrophages. OxLDL also induced a transient increase in the levels of � -glutamylcysteine syn- thetase heavy subunit ( � -GCS-HS), representing the cata- lytic subunit of the rate-limiting enzyme for de novo GSH synthesis. The induction took place within 3 h, with maxi- mum levels observed by 10 h of treatment. Pretreatment of oxLDL with ebselen inhibited GSH depletion and attenu- ated the � -GCS-HS induction. OxLDL-associated lipid hy- droperoxides and their decomposition product aldehydes are two major components thought to account for GSH de- pletion in macrophages. Ebselen pretreatment had only a minor effect on malondialdehyde levels, whereas peroxide content was essentially abolished, suggesting that oxLDL- associated hydroperoxides may mediate both GSH deple- tion and � -GCS-HS induction. Acetylated LDL (AcLDL) also caused a moderate induction of � -GCS-HS protein along with a 30% transient increase in GSH by 3-6 h, suggesting a minor involvement of scavenger receptor-mediated signal- ing of GSH synthesis. However, the level of � -GCS induc- tion by AcLDL was insufficient to cause a sustained increase in GSH. Macrophages with higher glutathione peroxidase (GPx) activity experienced a more rapid and extensive de- pletion of GSH when treated with oxLDL under similar conditions, along with greater resistance to oxLDL- or per- oxide-induced cytotoxicity. We conclude that oxLDL- associated peroxides are primarily responsible for GSH de- pletion, creating an oxidizing environment required for � -GCS induction and compensatory GSH synthesis. This is facilitated in cells expressing high GPx activity through a rapid depletion of GSH in the face of a peroxide challenge.— Shen, L., and A. Sevanian. OxLDL induces macrophage � -GCS-HS protein expression: a role for oxLDL- associated lipid hydroperoxide in GSH synthesis. J. Lipid Res. 2001. 42: 813-823.
Early Radiation Toxicity from Yttrium-90 Radioembolization for Advanced Hepatocellular Carcinoma.

Figure 1. Computed tomography of the chest on axial cuts (left) and sagittal cuts (right) at 10-week follow-up demonstrates central reticular and ground-glass opacities with sparing of both the perihilar and subpleural regions. A 56-year-old man with hepatitis B virus– associated cirrhosis and advanced hepatocellular carcinoma (HCC) presented with dyspnea. He was on therapy with sorafenib and had undergone radioembolization with yttrium 90 (Y) 5 days prior, which was complicated by a high shunt fraction (45%) resulting in an excessive lung radiation exposure of 55 Gy. A technetium-99m macroaggregated albumin (Tc-MAA) scan 1 week prior had demonstrated only a 22% shunt fraction, which would have resulted in a lung radiation dose of less than 30 Gy, the accepted safety standard. Although the initial chest radiograph was normal, given the patient’s symptoms of dyspnea and high dose of radiation exposure, empiric prednisone was prescribed at a dose of 20 mg daily in hopes of preventing radiation pneumonitis (RP). At 1 month follow-up, computed tomography of the chest was normal. Five weeks later, the patient was admitted with worsening dyspnea, and repeat computed tomography demonstrated bilateral ground-glass opacities with sparing of the perihilar regions and periphery (Figure 1). Bronchoscopy with bronchoalveolar lavage and multiple transbronchial biopsies in the affected region were negative for metastatic disease and did not identify any infectious organisms, including Pneumocystis, on special stains and molecular techniques. Histology showed nonspecific inflammation (Figure 2). Sorafenib was discontinued, and the glucocorticoid dose was increased to intravenous methylprednisolone at 60mg daily (equivalent to 1 mg/kg/d) for presumed RP. The patient continued to deteriorate despite therapy, Figure 2. Transbronchial biopsy yielded a 0.43 0.23 0.1–cm sample of alveolar tissue with anthracotic pigment deposition and minor inflammation with no granulomas, malignancy, or microorganisms seen. Cultures were negative (hematoxylin and eosin, 3100).
The Prophylactic Use–or Misuse–of Antibiotics in Transurethral Prostatectomy

AbstractOne hundred non-infeeted patients undergoing transurethral prostatectomy were randomized prospectively into a controlled study to determine the influence of a prophylactic aminoglycoside (kanamycin) on the clinical course. In the non-risk patient prophylactic kanamycin had no beneficial influence on the incidence of bacteriuria, fever or length of hospitalization. Its use was associated with the development of a resistant Pseudomonas super infection in 1 patient. Prophylactic kanamycin did not protect the patient with carcinoma of the prostate from bacteriuria. There was no identifiable advantage in the use of routine prophylactic kanamycin in the uninfected, non-risk patient who was undergoing elective transurethral prostatectomy.
STRAIN CORRELATIONS IN ALLOY 690 MATERIALS USING ELECTRON BACKSCATTER DIFFRACTION AND VICKERS HARDNESS

High chromium, nickel-base Alloy 690 exhibits an increased resistance to stress corrosion cracking (SCC) in pressurized water reactor (PWR) primary water environments over lower chromium alloy 600. As a result, Alloy 690 has been used to replace Alloy 600 for steam generator tubing, reactor pressure vessel nozzles and other pressure boundary components. However, recent laboratory crack-growth testing has revealed that heavily cold-worked Alloy 690 materials can become susceptible to SCC. To evaluate reasons for this increased SCC susceptibility, detailed characterizations have been performed on as-received and cold-worked Alloy 690 materials using electron backscatter diffraction (EBSD) and Vickers hardness measurements. Examinations were performed on cross sections of compact tension specimens that were used for SCC crack growth rate testing in simulated PWR primary water. Hardness and the EBSD integrated misorientation density could both be related to the degree of cold work for materials of similar grain size. However, a microstructural dependence was observed for strain correlations using EBSD and hardness which should be considered if this technique is to be used for gaining insight on SCC growth rates
Take the money and run: economic segregation in U.S. metropolitan areas.

Compared to residential segregation by race, economic segregation has received relatively little attention in recent empirical literature. Yet a heated debate has arisen concerning Wilson's (1987) hypothesis that increasing economic segregation among African Americans plays a role in the formation of urban ghettos. The author presents a methodological critique of the measure of economic segregation used by Massey and Eggers (1990) and he argues that their measure confounds changes in the income distribution with spatial changes. He develops a pure measure of economic segregation based on the correlation ratio and present findings for all U.S. metropolitan areas from 1970 to 1990. Economic segregation increased steadily for Whites, Blacks, and Hispanics in the 1970s and 1980s, but the increases have been particularly large and widespread for Blacks and Hispanics in the 1980s. The author explores the causes of these changes in a reduced-form, fixed-effects model. Social distance and structural economic transformations affect economic segregation, but the large increases in economic segregation among minorities in the 1980s cannot be explained by the model. These rapid increases in economic segregation, especially in the context of recent, albeit small, declines in racial segregation, have important implications for urban policy, poverty policy, and the stability of urban communities
Self-Concept and Achievement in Self-Enhancing Education

A self-enhancing education program was implemented in two elementary schools. In general, Ss showed an increase in cognitive skills but a decrease in self-concept. A positive correlation was shown ...
Intra-Latina/Latino encounters: Salvadoran and Mexican struggles and Salvadoran–Mexican subjectivities in Los Angeles

In the last 30 years, the mass transnational migration of Salvadorans and Mexicans to the U.S. from their countries due to changes in the world capitalist system, and its specific effects on their ...
Effect of Local and General Anesthetics on Interfacial Water

Background Water undergoes structural change as it interfaces with hydrophilic surfaces, including the many hydrophilic surfaces within the cell. This interfacial water has become known as “Exclusion Zone (EZ) water” or “fourth-phase water” [1]. Methods We tested the hypothesis that anesthetics diminish the amount of EZ water, and that this change may correlate with functional changes in anesthesia. By using the local anesthetics Lidocaine and Bupivacaine as well as a general inhalational anesthetic, Isoflurane, we tracked the EZ size as these anesthetics were introduced. Results All three anesthetics diminished EZ size in a concentration-dependent manner at concentrations of 0.18 mM and greater for Bupivacaine, 0.85 mM and greater for Lidocaine, and 0.2% for Isoflurane. At extremely low (micromolar) concentrations, however, all three anesthetics increased EZ size. Conclusions The sharp increase of EZ size associated with micromolar anesthetic concentrations follows a similar pattern to induction of general anesthesia, from the excitation stage (Stage II) to the depression and overdose stages of surgical anesthesia (Stages III and IV). The results are consistent with the hypothesis that anesthetics may act on water, a fundamental organizational component common to all cells.
Shape Change and the Percentage of Sialic Acid Removed by Neuraminidase from Human Platelets

SummaryThe sialic acid of human gelfiltered platelets was studied before and after ADP-induced shape change. Neuraminidase cleaved 47% of the total sialic acid from both discoid control platelets and platelets that had become spiny spheres after treatment with 5 μM ADP.We are grateful to the following colleagues for materials used in these experiments: Thomas H. Finlay, Ph.D., for the radiolabeled TAMe, Joel U. Harris, Ph.D., for the radiolabeled fibrinogen, Henriette Lackner, M. D., for the connective tissue suspension, and John Fenton, II, Ph.D. for the purified human thrombin.
In Vitro Derivation and Expansion of Endothelial Cells From Embryonic Stem Cells

Vascular endothelial cells or endothelial progenitor cells derived from stem cells could potentially lead to a variety of clinically relevant applications, including cell-based therapies and tissue engineering. Embryonic stem (ES) cells serve as an excellent in vitro system for studying differentiation events and for developing methods of generating various specialized cells for future regenerative therapeutic applications. Two obstacles associated with using embryonic stem cells include (1) isolating homogeneous populations of differentiated cells and (2) obtaining terminally differentiated cell populations that are capable of proliferating further. Here, we describe methods for isolating purified proliferating populations of endothelial cells from mouse ES cells using Flk-1-positive cells, vascular endothelial growth factor supplementation, and a highly selective manual selection technique. This methodology, although rigorous, overcomes two current obstacles in ES derivation and culture by generating highly purified (>96%) populations of actively proliferating endothelial cells from mouse ES cells. Using this in vitro derivation procedure, millions of cells at various stages of differentiation may be obtained and expanded up to 25 population doublings.