cssi/SciSciGPT-SciSciNet huggingface dataset:
Mechanism for Spiral Wave Breakup in Excitable and Oscillatory Media

We study spiral wave breakup using a Fitzhugh-Nagumo-type system. We find that spiral wave breakup can occur near the core or far from it in both excitable and oscillatory regimes. There is a faraway breakup scenario in both excitable and oscillatory media that depends on long wavelength modulation modes. We observed three distinct scenarios, including one that involves breakup that does not develop into turbulence. However, we find that the mechanisms behind these three scenarios are the same: they are caused by the interaction between the dispersion relation and the asymptotic behavior of the modulation mode. The difference in phenomenology is due to the asymptotic behavior of the modulation mode.
Ecological Distribution of Pesticides in Lake Poinsett, South Dakota

Abstract Ecological distributions of chlorinated hydrocarbon residues in Lake Poinsett, South Dakota were studied from June, 1967 to June, 1968. Components of the ecosystem analyzed were water, bottom sediments, zooplankton, benthic algae, crayfish, aquatic insects and fish. Concentrations of aldrin, p,p'-DDD, p,p'-DDE, p,p'-DDT, dieldrin, endrin, heptachlor, heptachlor epoxide, lindane, methoxychlor and toxaphene were determined by gas chromatography and thin-layer chromatography. DDT and its metabolites, DDD and DDE, were the highest residues detected in all trophic levels examined. Heptachlor, heptachlor epoxide, aldrin, dieldrin and lindane were present in the majority of sample types, while neither endrin nor methoxychlor was detected above analytical confidence limits in any sample. Toxaphene was present in four fish. DDT and metabolites increased in percentage of total residue, while the ratio of DDT to DDD plus DDE decreased with increase in trophic level. The ratio of the epoxide form of heptachl...
Statistical Analysis of Step Stress Measurements in Hardness Assurance

The technique of maximum likelihood analysis can solve previously unresolved problems which arise in step stress measurements where the failure levels for each device can only be bounded between two often widely separated limits. The proposed analysis would be necessary in correctly computing means, standard deviations and safe survival limits.
SU‐FF‐T‐80: Incorporation of Isodose‐Level Control to a Simplified Intensity‐Modulated Radiation Therapy (sIMRT) Technique for Whole Breast Radiotherapy

Purpose: To incorporate isodose‐level control in a simplified intensity‐modulated radiation therapy (sIMRT) technique (Med. Phys. 29, 522–529, 2002) for radiotherapy of large intact breast. Method and Materials: The parallel‐opposed tangential beam configuration has been used in many implementations of intensity‐modulated radiation therapy(IMRT) for large breast because of the dose constraints of contralateral breast and lung and the geographical constraint of breast target volume. For this beam configuration, a simplified IMRT (sIMRT) technique (Med. Phys. 29, 522–529, 2002), based on delivering equal prescription dose to the mid‐point of breast tissue seen by each pair of beamlets of intensity‐modulated 6 MV beams, provides efficient and robust IMRT planning. However, hot spots greater than 10% still exist near the base in the medial and lateral aspects of breast when the irradiated tissue in the beamlet path is greater than 20 cm. These beamlet paths often include part of ipsilateral lung and rib cage, to which the dose should be reduced. Modifications to the sIMRT algorithm were made so that dose to lung and consequently the hot spots in the medial and lateral aspects of breast can be reduced. Results: An automated algorithm, which delivers prescription dose to tissues near the lung‐breast tissue interface and to the mid‐point of the breast tissue, and a manual user‐definable isodose‐level control algorithm were developed and tested. Incorporation of these algorithms in sIMRT yielded lower dose to lung with smaller medial and lateral hot spots, in addition to the reduction of hot spots in the superior and inferior aspect of breast. Conclusion: sIMRT with isodose‐level control at the lung‐breast tissue interface near the base of large breast can be used efficiently for whole breast radiotherapy using the parallel‐opposed tangential beam setup.
Laser guide star adaptive optics at the Keck Observatory

This paper describes the upgrades to the Keck II Adaptive Optics (K2 AO) system needed for laser guide star observing. The upgrade, including integration with the laser, is scheduled for completion in the winter of 2003. This upgrade includes the addition of a Low Bandwidth Wavefront Sensor (LBWFS) measuring focus and higher order terms, and a Lawrence Livermore National Lab quad-lens avalanche photodiode detector which monitors tip/tilt. Both observe a dim natural guide star. LBWFS corrections are applied as corrections to the high bandwidth wavefront sensor, which is observing the laser beacon. These subsystems drive focus stages, a deformable mirror, a tip/tilt mirror for the incoming starlight, and a tip/tilt mirror for pointing the propagating laser beam. Taken together, and in concert with the rest of the components of the K2 AO system, they provide the tools and the means to observe the universe as never before.
Viewpoint on the echocardiographic presentations at the American College of Cardiology Annual Scientific Sessions.

Summary Overall, echocardiography was well represented at the American College of Cardiology Annual Scientific Sessions and accounted for input into almost 25% of all abstracts presented. This included not only specialized sessions, predominantly attended by echocardiographers, but the clinical and surgical sessions dealing with virtually any and all forms of heart disease. This is a versatility of which we can be justifiably proud. The newer technique of cathetermounted ultrasound transducers for intravascular imaging is exciting, and we all await further developments in this field. Finally, it would appear the ground is still fertile for investigation into left ventricular function as it relates to acute myocardial infarction in an era of evermore frequent intervention.
The distribution of lobate debris aprons and similar flows on Mars

Planet-wide mapping of lobate debris aprons and other similar flows on Mars shows a strong concentration in two latitudinal bands roughly 25° wide and centered at 40°N and 45°S. This distribution supports the idea that these flows form when erosional debris is transported downslope and becomes mixed with ice deposited from the atmosphere, as these latitudes should receive high seasonal H2O frost deposition relative to the rest of the planet. Flows are found in the northern hemisphere band wherever old highland surfaces occur but are found in the southern hemisphere only near the two major impact basins, Argyre and Hellas. These areas are apparently characterized by mass wasting that is rapid relative to most of the southern hemisphere highlands. The rate of mass wasting may be related to the degree of consolidation of highland material.
Neoral induction in pediatric renal transplantation

Neoral was instituted in pediatric renal transplant patients with the hypothesis it would have more predictable kinetics than Sandimmun. However, significant questions have arisen concerning potential toxicity and dosing interval related to its rapid absorption with subsequent high initial peak. This is compounded by the fact that children appear to metabolize cyclosporine at a greater rate than adults. This combination of a rapid peak and rapid absorption may then result in lower trough levels at 12 h. We compared the trough cyclosporine levels of nine children who received Neoral with nine who received Sandimmun at the time of initial transplantation. More frequent dosing (every 8 h) was required in the Neoral population compared with the Sandimmun population for the 1st month in order to obtain comparable trough levels. Beyond the initial 4–6 weeks, trough levels were similar for Neoral and Sandimmun. Whereas 1-month creatinine levels and blood pressures were similar, the number of blood pressure medications was significantly higher in the Neoral group. At 5.5 ± 1.1 months’ followup, a single patient in the current Neoral group and in the retrospective Sandimmun group each experienced a single OKT3 allograft-treated rejection. We suggest that the area under the curve is different in Neoral than Sandimmun, and the initial dosing frequency may need to be adjusted accordingly.
Axial symmetric configuration of Q matter in an Ernst space-time background

An axial symmetric configuration of SO2-invariant Q matter is studied in a background of Ernst space-time. Though the model studied represents the simplest model possible, it is suggestive of how Q-matter-like configurations might appear in the atmosphere of a black hole immersed in a uniform magnetic field.
DRUG DISCRIMINATION IN RATS UNDER CONCURRENT VARIABLE‐INTERVAL VARIABLE‐INTERVAL SCHEDULES

Eight rats were trained to discriminate pentobarbital from saline under a concurrent variable-interval (VI) VI schedule, on which responses on the pentobarbital-biased lever after pentobarbital were reinforced under VI 20 s and responses on the saline-biased lever were reinforced under VI 80 s. After saline, the reinforcement contingencies programmed on the two levers were reversed. The rats made 62.3% of their responses on the pentobarbital-biased lever after pentobarbital and 72.2% on the saline-biased lever after saline, both of which are lower than predicted by the matching law. When the schedule was changed to concurrent VI 50 s VI 50 s for test sessions with saline and the training dose of pentobarbital, responding on the pentobarbital-biased lever after the training dose of pentobarbital and on the saline-biased lever after saline became nearly equal, even during the first 2 min of the session, suggesting that the presence or absence of the training drug was exerting minimal control over responding and making the determination of dose-effect relations of drugs difficult to interpret. When the pentobarbital dose-response curve was determined under the concurrent VI 50-s VI 50-s schedule, responding was fairly evenly distributed on both levers for most rats. Therefore, 6 additional rats were trained to respond under a concurrent VI 60-s VI 240-s schedule. Under this schedule, the rats made 62.6% of their responses on the pentobarbital-biased lever after pentobarbital and 73.5% of their responses on the saline-biased lever after saline, which also is lower than the percentages predicted by perfect matching. When the schedule was changed to a concurrent VI 150-s VI 150-s schedule for 5-min test sessions with additional drugs, the presence or absence of pentobarbital continued to control responding in most rats, and it was possible to generate graded dose-response curves for pentobarbital and other drugs using the data from these 5-min sessions. The dose-response curves generated under these conditions were similar to the dose-response curves generated using other reinforcement schedules and other species.
Sex Differences in Use of Coronary Revascularization in Elderly Patients After Acute Myocardial Infarction* A Tale of Two Therapies

Objectives To determine if there are sex differences in the use of coronary revascularization in elderly patients after acute myocardial infarction (AMI), and if sex differences vary by type of revascularization therapy. Design Retrospective analysis of medical record data. Setting US acute-care nongovernment hospitals. Patients A total of 66,830 Medicare patients ≥ 65 years old hospitalized with AMI. Interventions None. Measurements and results We assessed sex differences in the use of coronary revascularization within 60 days of hospital admission among patients who had undergone cardiac catheterization. Multivariable logistic regression models were used to derive risk-standardized rates of any coronary revascularization, coronary artery bypass graft (CABG) surgery, and percutaneous coronary intervention (PCI) adjusted for patient and hospital characteristics. Women had lower crude overall rates of coronary revascularization compared with men (65.2% vs 68.7%, p 85 years old (45.8% vs 38.9%, p = 0.011). Conclusions Among Medicare patients hospitalized with AMI, women are slightly less likely to undergo coronary revascularization after cardiac catheterization; however, sex differences in coronary revascularization vary by type of therapy.
Bid/no-bid decision-making – a fuzzy linguistic approach

Abstract Bid/no-bid decision-making is a critical activity for a contractor. Limited by both the nature of and the competition for bid opportunities, bid/no-bid decision is associated with uncertainty and complexity. Because subjective considerations such as nature, competition, value of the bid opportunity, resource capabilities, and the reputation of the company are relevant to the bid/no-bid decision, a fuzzy logic approach is adopted. In this approach assessments are described subjectively in linguistic terms, while screening criteria are weighted by their corresponding importance using fuzzy values. As an illustration, a practical example for evaluating a bid opportunity of an international co-development commercial airplane project in Taiwan is cited, which shows how this method can provide the analyst with more convincing and reliable results and cost saving for the company.
Mechanical impedance and impact response of the human cadaver zygoma.

Abstract The use of mechanical impedance techniques and steady-state vibration response is shown to have a definite correlation with the impact characteristics of the human cadaver zygoma. This work complements previous work concerning the response of the zygoma to an impulsive force and yields greater insight into the mechanism of human tolerance to blunt trauma.
Solvent oxygen is not incorporated into N10-formyltetrahydrofolate in the reaction catalyzed by N10-formyltetrahydrofolate synthetase

The mechanism of the reaction catalyzed by N10-formyltetrahydrofolate synthetase involves the formation of formyl phosphate as an intermediate which then formylates tetrahydrofolate at the N-10 position. Previous studies demonstrated that the non-enzymic formylation of tetrahydrofolate by formyl phosphate occurs exclusively at the more nucleophilic 5-nitrogen in the reduced pyrazine ring. The experiments described in this report were designed to determine whether N5-formyltetrahydrofolate might be the first product to be formed on the enzyme, followed by formyl transfer to the 10-nitrogen via the cyclic intermediate n5,10-methenyltetrahydrofolate. If this were the case, oxygen from solvent H2O would be incorporated into the formyl group of the N10-derivative. By conducting the reaction in a 1:1 mixture of [16O]H2O and [18O]H2O and using 13C NMR spectroscopy we show that no 18O is incorporated into the product and conclude that the reaction proceeds via a direct formylation of the N-10 position by formyl phosphate.
Chemical modification studies on the α-d-galactopyranosyl binding lectin from the seeds of Bandeiraea simplicifolia

Abstract The role of amino, carboxyl and sulfhydryl groups in the binding of carbohydrate ligands to the α- d -galactopyranosyl binding lectin from Bandeiraea simplicifolia has been evaluated using specific chemical modification techniques. The results indicate that carboxyl groups participate in the carbohydrate binding phenomenon, whereas free amino and sulfhydryl groups do not appear to be directly involved.
Absence of normal activation of the left anterior fusiform gyrus during naming in left temporal lobe epilepsy

Patients with left temporal lobe epilepsy (TLE) often have impaired naming. We studied 13 patients with left TLE and 10 healthy control subjects with [ 15 O]H 2 O PET during visual confrontation naming. Statistical mapping detected multiple regions of significant cerebral blood flow increases within individuals . The left fusiform gyrus was activated in nine healthy subjects, but only in two patients with TLE (a significant difference, p
Accurate gaussian laser beam diameter measurement using exponential and rectified sinusoidal rulings

Novel exponential and rectified sinusoidal gratings for the measurement of Gaussian laser beam diameter are proposed. It is found that these gratings provide accurate measurement for both small and large Gaussian beam diameters.
On Rossby waves in spiral galaxies

Galactostrophic eddy velocities are used to eliminate the dependence of the potential vorticity equation on the velocities. The resultant time dependent equation involves the mass densities alone. DOI: 10.1111/j.2153-3490.1964.tb00172.x
In vitro characterization of vascular endothelial growth factor and dexamethasone releasing hydrogels for implantable probe coatings

Anti-fouling hydrogel coatings, copolymers of 2-hydroxyethyl methacrylate, 1-vinyl-2-pyrrolidinone, and polyethylene glycol, were investigated for the purpose of improving biosensor biocompatibility. These coatings were modified to incorporate poly(lactide-co-glycolide) (PLGA) microspheres in order to release dexamethasone (DX) and/or vascular endothelial growth factor (VEGF). DX and VEGF release kinetics from microspheres, hydrogels, and microspheres embedded in hydrogels were determined in 2-week and 1-month studies. Overall, monolithic, non-degradable hydrogel drug release had an initial burst followed by release at a significantly lower amount. Microsphere drug release kinetics exhibited an initial burst followed by sustained release for 1 month. Embedding microspheres in hydrogels resulted in attenuated drug delivery. VEGF release from embedded microspheres, 1.170.3 ng, was negligible compared to release from hydrogels, 197733 ng. After the initial burst from DX-loaded hydrogels, DX release from embedded microspheres was similar to that of hydrogels. The total DX release from hydrogels, 155735mg, was greater than that of embedded microspheres, 6076mg. From this study, hydrogel sensor coatings should be prepared incorporating VEGF in the hydrogel and DX either in the hydrogel or in DX microspheres embedded in the hydrogel. r 2004 Published by Elsevier Ltd.
Transcriptional Regulation of the Human μ Opioid Receptor (hMOR) Gene: Evidence of Positive and Negative Cis-Acting Elements in the Proximal Promoter and Presence of a Distal Promoter

The μ opioid receptor (MOR), the primary binding site for morphine, is an important target for treating pain and drug addiction. The MOR gene is tightly regulated at the level of transcription, and...
Migration of Large Gas‐Filled Pores in Potassium Chloride Due to a Temperature Gradient

The migration of gas-filled pores in KCl subjected to a temperature gradient occurs by a vaporization-condensation mechanism. In many cases the vaporization step, rather than gas-phase diffusion, can limit the rate of migration. Movement of large (>100 /mu/m), argon-filled pores in pure and Ba-doped KCl was observed using hot-stage microscopy. Velocities of large pores in pure KCl were limited by the diffusion rates of KCl monomers and dimers in argon. This observation is consistent with a model in which the vaporization rate is moderately reduced due to widely spaced surface ledges, but is still rapid with respect to gas-phase diffusion. The velocities of large pores in 10 and 40 ppm Ba-doped samples were significantly lower than those in pure samples. A model was developed which explains these decreased migration rates in terms of impurity poisoning of surface kink sites. The model couples detailed expressions for vaporization kinetics with those for gas-phase diffusion rates. 37 refs.
Tribological and Mechanical Properties of Fe/Ti Multilayered films

A 900 {angstrom} as-deposited multilayered structure of alternating Fe and Ti on hardened tool steel has been examined for tribological and mechanical properties. The multilayer in contact with a 521000 steel ball counter surface possessed a 0.16 friction coefficient and showed good wear character after 1000 cycles in pin-on-disk experiments. Nanoindentation experiments show a 20% increase in hardness for material in the wear track. Electron microscopy shows that the as-deposited bcc-Fe plus hcp-Ti multilayer composite transforms to a nanocrystalline alloy plus bcc-Fe by solid state reaction during pin-on-disk friction and wear tests. The low friction observed in these surface films is attributed to the formation of a hard nanocrystalline alloy and improved interlayer and film/substrate adhesion which result during solid state reaction. 10 refs., 4 figs.
Application of real-time spectroscopic ellipsometry for characterizing the structure and optical properties of microcrystalline component layers of amorphous semiconductor solar cells

Abstract Over the past few years, we have applied real-time spectroscopic ellipsometry (RTSE) to probe hydrogenated amorphous silicon (a-Si:H)-based solar cell fabrication on the research scale. From RTSE measurements, the microstructural development of the component layers of the cell can be characterized with sub-monolayer sensitivity, including the time evolution of (i) the bulk layer thickness which provide the deposition rates, and (ii) the surface roughness layer thickness which provide insights into precursor surface diffusion. In the same analysis, RTSE also yields the optical properties of the growing films, including the dielectric functions and optical gaps. Results reported earlier have been confined to p-i-n and n-i-p cells consisting solely of amorphous layers, because such layers are found to grow homogeneously, making data analysis relatively straightforward. In this study, we report the first results of an analysis of RTSE data collected during the deposition of an n-type microcrystalline silicon (μc-Si:H) component layer in an a-Si:H p-i-n solar cell. Such an analysis is more difficult owing to (i) the modification of the underlying i-layer by the H2-rich plasma used in doped μc-Si:H growth and (ii) the more complex morphological development of μc-Si:H, including surface roughening during growth.
Current and future applications of mycobacterial amplification assays

Introduct ion During the last 2 to 3 yr, numerous articles have been published concerning the reemergence of tuberculosis in the U.S. This resurgence was a result of a number of complex factors, among them homelessness and other socioeconomic factors, the human immunodeficiency virus (HIV) epidemic, and hospital and other group-setting outbreaks of tuberculosis. Further complicating these outbreaks were frequent delays in laboratory repotting of smear, culture, and/or susceptibility test resuits. As a consequence, an important question was raised as to how one could provide a more rapid diagnosis for tuberculosis given the urgent need. Because of the obvious demand for a reliable and rapid means of diagnosing tuberculosis for public health and therapeutic reasons, the discovery of the polymerase chain reaction (PCR) about 10 yr ago, with its potential ability to exponentially copy virtually any targeted sequence of DNA in an afternoon, is particularly attractive. Since PCR's discovery, a number of other approaches to amplification have also been introduced to detect Mycobacterium tuberculosis (MTB) directly in clinical specimens; some of these amplification formats are listed in Table 1. Regardless of the format, these amplification assays show promise as rapid, sensitive, and specific methods to diagnose tuberculosis. Despite the significant promise these assays hold for improved laboratory diagnosis of tuberculosis, a number of issues must be considered by clinical microbiologists before these assays are introduced into the laboratory routine. Key issues include expense, the assays' exact role in the diagnosis of mycobacterial infections, and their clinical utility. In this article, I would like to discuss important issues concerning these assays and then suggest some possible immediate and future applications for them. However, if these issues are to be fully appreciated, a brief summary of data published to date is prerequisite.
The Department of Veterans Affairs smoke-free policy.

THE Department of Veterans Affairs (VA), the largest health care provider in the United States, implemented an agency policy on January 7, 1991, requiring all 172 acute-care hospitals to be completely smoke-free.1-3The VA initiative followed directives by other government agencies for smoke-free environments, such as the US Army4and the Indian Health Service.5Smoke-free hospitals have been endorsed by the American Medical Association, the American College of Physicians, and the US Preventive Services Task Force, as well as other organizations.6 This policy was written in a national climate that is increasingly intolerant of environmental tobacco smoke, although hospitals commonly continue to allow smoking in designated areas. Several medical centers have become completely smoke-free,7-13and the states of Minnesota and Maine have passed legislation requiring health care institutions to be smoke-free. Because of the national trend in legislation of public smoking (including the Joint Commission
Optical studies of locally implanted magnetic ions in GaAs

We report the development of a ${\mathrm{Mn}}^{2+}$ focused ion beam for use in the direct fabrication of submicrometer magnetic structures. Mn-implanted GaAs bulk epilayers and quantum wells are studied by low-temperature cathodoluminescence and polarization-resolved photoluminescence. The data demonstrate that Mn ions are magnetically active, producing optical polarizations of 70% at 8 T.
Toward a holistic approach to communication: The effect of “pure” hemispheric reception on message acceptance

This study examined the relationship between hemispheric processing of complex messages and message acceptance. In particular the research sought to answer several questions regarding the processing and interpretation of persuasive messages and message sources. Based on the results of this research it was concluded that (1) the brain's right and left hemispheres, when isolated from one another, process information according to a particular “style,” (2) that semantic properties of language influence hemispheric processing, and (3) that message sources are perceived differently by the right and left hemispheres. Potential implications for the study of communication in terms of message style and acceptability, language intensity, perceptions of source, and perceptions of threat conclude this analysis.
Modeling and predicting seasonal influenza transmission in warm regions using climatological parameters.

Background Influenza transmission is often associated with climatic factors. As the epidemic pattern varies geographically, the roles of climatic factors may not be unique. Previous in vivo studies revealed the direct effect of winter-like humidity on air-borne influenza transmission that dominates in regions with temperate climate, while influenza in the tropics is more effectively transmitted through direct contact. Methodology/Principal Findings Using time series model, we analyzed the role of climatic factors on the epidemiology of influenza transmission in two regions characterized by warm climate: Hong Kong (China) and Maricopa County (Arizona, USA). These two regions have comparable temperature but distinctly different rainfall. Specifically we employed Autoregressive Integrated Moving Average (ARIMA) model along with climatic parameters as measured from ground stations and NASA satellites. Our studies showed that including the climatic variables as input series result in models with better performance than the univariate model where the influenza cases depend only on its past values and error signal. The best model for Hong Kong influenza was obtained when Land Surface Temperature (LST), rainfall and relative humidity were included as input series. Meanwhile for Maricopa County we found that including either maximum atmospheric pressure or mean air temperature gave the most improvement in the model performances. Conclusions/Significance Our results showed that including the environmental variables generally increases the prediction capability. Therefore, for countries without advanced influenza surveillance systems, environmental variables can be used for estimating influenza transmission at present and in the near future.
Genetic aspects of the synthesis of catecholamines in the adrenal medulla.

Abstract (1) There are marked strain differences in the activity of the enzymes involved in the synthesis of the adrenal medullary hormones within a series of inbred mouse strains. (2) In the case of tyrosine hydroxylase, the rate-limiting step in the formation of catecholamines, differences of as much as fourfold have been found, while for phenylethanolamine N-methyl transferase, the enzyme which converts norepinephrine to epinephrine, differences of 2·5-fold have been noted. (3) Genetic studies of the strains provide evidence that genetic factors are very important in determining the activity of the enzymes involved in catecholamine formation. (4) Major differences in regulatory mechanisms involving the enzymes can also be demonstrated between the strains. (5) Such differences in the capacity to form catecholamines may have significance in the response to stress and in behavior.
Inpatient violence: trait and state

This study compared patients who showed persistent violence, transient violence and no violence. The presence of neurological abnormalities was found to be the factor that differentiated most clearly among the three groups. The persistently violent patients, in addition to showing significantly more neurological abnormalities, also evidenced a more disturbed family background. Both violent groups had a higher incidence of violent crime prior to hospitalization than the nonviolent controls. A logistic regression model simultaneously relating the effects of six factors on violent behavior was developed and used to predict violent group membership.
Cyclin-dependent Kinase 2 Negatively Regulates Human Pregnane X Receptor-mediated CYP3A4 Gene Expression in HepG2 Liver Carcinoma Cells

The human pregnane X receptor (hPXR) regulates the expression of critical drug metabolism enzymes. One of such enzymes, cytochrome P450 3A4 (CYP3A4), plays critical roles in drug metabolism in hepatocytes that are either quiescent or passing through the cell cycle. It has been well established that the expression of P450, such as CYP3A4, is markedly reduced during liver development or regeneration. Numerous studies have implicated cellular signaling pathways in modulating the functions of nuclear receptors, including hPXR. Here we report that inhibition of cyclin-dependent kinases (Cdks) by kenpaullone and roscovitine (two small molecule inhibitors of Cdks that we identified in a screen for compounds that activate hPXR) leads to activation of hPXR-mediated CYP3A4 gene expression in HepG2 human liver carcinoma cells. Consistent with this finding, activation of Cdk2 attenuates the activation of CYP3A4 gene expression. In vitro kinase assays revealed that Cdk2 directly phosphorylates hPXR. A phosphomimetic mutation of a putative Cdk phosphorylation site, Ser350, significantly impairs the function of hPXR, whereas a phosphorylation-deficient mutation confers resistance to Cdk2. Using HepG2 that has been stably transfected with hPXR and the CYP3A4-luciferase reporter, enriched in different phases of the cell cycle, we found that hPXR-mediated CYP3A4 expression is greatly reduced in the S phase. Our results indicate for the first time that Cdk2 negatively regulates the activity of hPXR, and suggest an important role for Cdk2 in regulating hPXR activity and CYP3A4 expression in hepatocytes passing through the cell cycle, such as those in fetal or regenerating adult liver.
Scale effects on the elastic behavior of periodic andhierarchical two-dimensional composites

Abstract The apparent stiffness tensors of two-dimensional elastic composite samples smaller thanthe representative volume element (RVE) are studied as a function of system size. Numericalexperiments are used to investigate how the apparent properties of the composite converge withincreasing scale factor n, defined to be the ratio between the linear size of the composite and thelinear size of the unit cell. Under affine (Dirichlet-type) or homogeneous stress (Neumann-type) boundary conditions, the apparent elastic moduli overestimate orunderestimate, respectively, the effective elastic moduli of the infinitely periodic system. Theresults show that the difference between the Dirichlet, Neumann and the effective stiffnesstensors depends strongly on the phase stiffness contrast ratio. Dirichlet boundary conditionsprovide a more accurate estimate of the effective elastic properties of stiff matrix composites,whereas Neumann boundary conditions provide a more accurate estimate for compliant matrixstructures. It is shown that the apparent bulk and shear moduli may lie outside of theHashin–Shtrikman bounds. However, these bounds provide good upper and lower estimates forthe apparent bulk and shear moduli of structures with a scale factor n ⩾ 2. A similar approach isused to study hierarchical composites containing two distinct structural levels with a finiteseparation of length scales. It is shown, numerically, that the error associated with replacing thesmallest-scale regions by an equivalent homogeneous medium is very small, even when the ratiobetween the length scales is as low as three.
Intracardiac ultrasound determination of left ventricular volumes: in vitro and in vivo validation.

AbstractObjectives. This study was designed to assess the feasibility of calculating left ventricular volumes using intracardiac ultrasound.Background. Previous studies have validated transthoracic...
Outcome Determinants in Uterine Papillary Serous Carcinoma Based on Clinicopathological and Treatment Factors

Purpose/Objective(s): Stage II endometrial cancer is relatively uncommon. There is no consensus for appropriate adjuvant therapy in endometrial cancer patients with cervical stromal involvement (FIGO stage II). This study investigates how adjuvant treatments and tumor characteristics influence OS and DFS in stage II patients in order to establish better treatment guidelines. Materials/Methods: This multi-institution, IRB approved, study is a retrospective review of 40 surgically staged endometrial cancer patients with cervical stromal involvement treated from 1993 to 2009. KaplanMeier estimates were used to evaluate OS and DFS. Results: The average age for all patients was 61 (36-83). Patient OS was 85% at three years and 67% at five years. There were no significant differences in age, histology, depth of invasion, comorbid conditions, surgical staging or recurrence between patients who received RT and those who did not receive RT. However, patients with FIGO grade 1 cancers were less likely to receive RT (p<0.007). Patients treated with RT had a similar 5 year OS (nZ33, 69%) to those treated with surgery only (nZ7, 60%, pZ0.7462). There were no OS differences when evaluating by grade, histology, or depth of invasion between patients who did and did not receive RT. Four patients recurred out of the 40 who were treated. Patient, tumor and treatment characteristics are outlined in table 1. Three were local recurrences, and one presented with concurrent local and distant failure. Our only vaginal cuff recurrence had a grade 1 tumor and had not received adjuvant RT, but was salvaged with RT in a timely manner after the recurrence. The remaining three recurrences occurred in patients who received radiation near the time of surgery, and all died from complications related to their cancer after recurrence. Conclusions: In this retrospective series, patients receiving RT had higher grade tumors. Despite this, OS was comparable between the RT and the no RT cohorts. Endometrial cancer patients with cervical stromal involvement likely receive better locoregional control with the addition of adjuvant RT, and we continue to advocate for RT in most cases. Author Disclosure: J. Frandsen: None. W.T. Sause: None. M.K. Dodson: None. A.P. Soisson: None. T.W. Belnap: None. D.K. Gaffney: None.
Total cholesterol levels and mortality risk in nonischemic systolic heart failure

Background Prior studies have demonstrated that low serum total cholesterol (TC) is associated with increased mortality in heart failure (HF); however, this association has not been consistently observed in HF of nonischemic etiology. Methods We analyzed a cohort of 614 patients with nonischemic systolic HF (left ventricular ejection fraction [LVEF] 210 mg/dL). Results The cohort was 68% male, mean age was 48 ± 13 years, and LVEF was 23% ± 7%. Patients with lower serum TC had worse hemodynamic profiles, lower LVEF, and higher New York Heart Association class. Low TC was associated with increased risk of 1-year death and urgent transplant (UT) (49%, 29%, 18%, 14% for Q1-Q4 respectively, P P Conclusions Low TC is strongly associated with increased mortality in patients with nonischemic, systolic HF. Further research is necessary to determine the nature of this relationship, optimal lipid levels, and the therapeutic role, if any, of statins in patients with established HF.
Effects of binge alcohol exposure in the second trimester on intracerebral arteriolar function in third trimester fetal sheep.

Abstract Fetal alcohol syndrome is a leading cause of mental retardation, but mechanisms of alcohol-associated brain damage remain elusive. Chronic alcohol exposure attenuates fetal and neonatal hypoxic cerebral vasodilation in sheep. We therefore hypothesized that alcohol could alter development of cerebrovascular responses to adenosine, a putative mediator of hypoxic cerebral vasodilation. The objective of this study was to examine the effect of earlier fetal alcohol exposure on later reactivity to adenosine in fetal sheep cerebral arterioles. Penetrating intracerebral arterioles were harvested from the brains of third trimester fetal sheep previously exposed in the second trimester to maternal alcohol “binges” (1.5 g/kg IV over 90 min, 5 days/week for 4 weeks) or same-volume saline infusions. Arterioles were cannulated with a micropipette system and luminally pressurized. Fetal alcohol exposure did not affect spontaneous myogenic tone, but enhanced the dilator response of penetrating arterioles to extraluminal acidosis (pH 6.8). Alcohol exposure also resulted in an increase in maximal vessel response to CGS-21680, an adenosine A 2A receptor agonist, but did not alter the concentration-dependent response curves to adenosine. Our results suggest that earlier alcohol exposure does not impair the subsequent responsiveness of fetal cerebral arterioles to vasodilator agents. Thus, alteration in cerebral vascular response to hypoxia in fetal sheep may not be attributed to changes in vascular reactivity to adenosine.
Impact of TDDB in MG/HK devices on circuit functionality in advanced CMOS technologies

The impact of time-dependent dielectric breakdown (TDDB) in metal gate (MG) / high-k (HK) devices on CMOS circuit functionality is examined using a novel fast PCI card based characterization setup. Detailed information on the role of the driver resistance on circuit failure is provided. By comparing breakdown in circuits to TDDB characteristics in discrete devices, it is shown that soft breakdown in the cross-coupled inverter circuit is well-correlated with soft breakdown in discrete CMOS devices. However, in all cases studied, it is observed that immediate circuit failure during high voltage stress is prevented by the resistance of the driver element. Implications of these findings on circuit lifetime assessment are discussed.
Altered cerebral blood flow and neurocognitive correlates in adolescent cannabis users

Rationale The effects of adolescent marijuana use on the developing brain remain unclear, despite its prevalence. Arterial spin labeling (ASL) is a noninvasive imaging technique that characterizes neurovascular status and cerebral blood flow (CBF), potentially revealing contributors to neuropathological alterations. No studies to date have looked at CBF in adolescent marijuana users.
Overview of small optics for the National Ignition Facility

LLNL's project to construct the National Ignition Facility (NIF), a 192 beam laser system capable of generating enough light energy necessary to achieve fusion ignition, will require 26,641 small optics, many of which will be supplied in the form of cleaned, tested and aligned assemblies. These assemblies will be built to print, cleaned to specifications, and tested to performance specifications, ready to be installed in the laser system. A wide range of potential suppliers will participate in the manufacture of these sophisticated opto-mechanical systems. The injection laser system requires 7,440 precision optical components manufactured to state of the art performance specifications. In addition to 550 aspheric lenses, almost 2,000 precision spherical elements are required. Wave-fronts are specified in terms of P-V, RMS and RMS Gradient wave-front error, with strict requirements on the filtering and resolution which is required. Precision polarizers, high reflectors, leaking mirrors, high damage threshold coatings and cleanliness levels of 50 to 100 are also specified for this section of the NIF laser. The alignment and diagnostics systems for the NIF require 19,201 optics, many of which have requirements that exceed those of the injection laser system. All of these optics will be purchased using the ISO 10110 drawing notations. Other sections of the laser system will utilize commercial, off the shelf components to control cost. This paper will give an overview of the project and its objectives, with specific attention to the small optics required for the NIF.
Globalization, Political Institutions and the Environment in Developing Countries

The Environmental Kuznets Curve (EKC) is a concept that has been employed in numerous scholarly venues and for many years. Much interest in it extends from its seeming good common sense—that pollut...
Modeling biocide action against biofilms.

A phenomenological model of biocide action against microbial biofilms was derived. Processes incorporated in the model include bulk flow in and out of a well-mixed reactor, transport of dissolved species into the biofilm, substrate consumption by bacterial metabolism, bacterial growth, advection of cell mass within the biofilm, cell detachment from the biofilm, cell death, and biocide concentration-dependent disinfection. Simulations were performed to analyze the general behavior of the model and to perform preliminary sensitivity analysis to identify key input parameters. The model captured several general features of antimicrobial agent action against biofilms that have been observed widely by experimenters and practitioners. These included (1) rapid disinfection followed by biofilm regrowth, (2) slower detachment than disinfection, and (3) reduced susceptibility of microorganisms in biofilms. The results support the plausibility of a mechanism of biofilm resistance in which the biocide is neutralized by reaction with biofilm constituents, leading to a reduction in the bulk biocide concentration and, more significantly, biocide concentration gradients within the biofilm. Sensitivity experiments and analyses identified which input parameters influence key response variables. Each of three response variables was sensitive to each of the five input parameters, but they were most sensitive to the initial biofilm thickness and next most sensitive to the biocide disinfection rate coefficient. Statistical regression modeling produced simple equations for approximating the response variables for situations within the range of conditions covered by the sensitivity experiment. The model should be useful as a tool for studying alternative biocide control strategies. For example, the simulations suggested that a good interval between pulses of biocide is the time to minimum thickness. © 1996 John Wiley & Sons, Inc.
Supercritical carbon dioxide-brine-rock reactions in the Madison Limestone of Southwest Wyoming: An experimental investigation of a sulfur-rich natural carbon dioxide reservoir

Abstract The Madison Limestone on the Moxa Arch, southwest Wyoming, USA is a sulfur-rich natural CO 2 reservoir. A series of hydrothermal experiments was performed to evaluate multi-phase (CO 2 –H 2 O)–brine–rock reactions and processes in this reservoir and to test the hypothesis that this reservoir is a natural analog for geologic carbon–sulfur co-sequestration. Idealized Madison Limestone (dolomite–calcite–anhydrite–pyrite) and Na–Cl–SO 4 2 − brine (I = 0.5 molal) reacted at 110 °C and 25 MPa for approximately 81 days (1940 h). Supercritical CO 2 was then injected and the experiment continued for approximately 46 days (1100 h). A parallel experiment was performed without supercritical CO 2 to provide a basis of understanding for the interaction of supercritical CO 2 with the brine–rock system. Two additional experiments were conducted in the same manner, but without anhydrite in the starting mineral assemblage, to examine supercritical CO 2 –sulfur reactivity. Injection of supercritical CO 2 decreases pH by 2.5 to 3.3 units, increases Eh by 0.19 to 0.23 V, and drives reaction pathways along the pyrite–anhydrite saturation boundary of an Eh–pH diagram. The dolomite–calcite–anhydrite mineral assemblage and reaction textures that are produced are consistent with those observed in the natural CO 2 reservoir. The mineral assemblage does not change following emplacement of supercritical CO 2 ; instead, minerals dissolve, mobilize and re-precipitate. Anhydrite precipitates in the dolomite–calcite–pyrite experiment following injection of supercritical CO 2 and provides a mineral trap for sulfur. Anhydrite precipitation decreases SO 4 2 − activity, ultimately leading to mineralization of CO 2 . Experimental results support the hypothesis that the Madison Limestone on the Moxa Arch is a natural analog for geologic carbon-sulfur co-sequestration.
Climate and culture : interaction and qualitative differences in organizational meanings

Etude de la relation entre l'appartenance des individus a des groupes d'interaction sociale et les significations qu'ils donnent aux evenements dans l'organisation. Selon l'hypothese, les individus qui ont interagis ensemble interpreteraient qualitativement de facon similaire les evenements de l'organisation tandis que differents groupes d'interaction interpreteraient differemment les memes evenements organisationnels. Entretien et questionnaire. N=64. Analyse de structure et echelle multidimensionnelle