cssi/SciSciGPT-SciSciNet huggingface dataset:
Preparation and crystal structures of tetrakis(methyltrihydroborato)uranium(IV)bis(tetrahydrofuranate) and tetrakis(methyltrihydroborato)uranium(IV)tetrahydrothiophenate

Abstract The U(IV) complexes, U(BH3CH3)·20C4H8 and [U(BH3CH3)4·SC4H8]2, have been prepared and their structures determined. Crystals of (BH3CH3)4U·20C4H8 are orthorhombic, Aba2, with a=12.911(3), b=16.072(4), c=10.116(4) A, at 23 °C. For Z=2 the calculated density is 1.574 g/cm3. Crystals of [(CH3BH3)4U·SC4H8]2 are monoclinic, P2 1 /c, with a=12.054(2), b=16.372(3), c= 18.545(3) A and β=108.82(2)° at 23 °C. For Z=4 the calculated density is 1.694 g/cm3. The structures were refined by full-matrix least-squares to a conventional R factor of 0.028, [1378 data, F2>;2σ(F2)] for the tetrahydrofuran complex, and 0.038 [2732 data, F2>;2σF2] for the tetrahydrothiophen plex. The tetrahydrofuran complex is monomolecular with the uranium atom on a two-fold axis and coordinated to four methyltrihydroborato and two tetrahydrofuran ligands; the UB distances are 2.55(2)and 2.58(2) A, and the UO distance is 2.485(6) A. The tetrahydrothiophene complex is a dimer in which two sulfur atoms bridge the uranium atoms of two tetra(methyltrihydroborato)uranium(IV) molecules; the UB distances range from 2.468(2) to 2.591(2) A, and the US distances are 3.120(4) and 3.239(5) A; the SS and UU distances in the bridge are 3.477(5) and 5.374(1) A, respectively.
Kinetic approach to multiple pathway diffusion with traps

Multiple pathway diffusion with traps was analyzed in the kinetic approach in which the diffusion terms in the diffusion-kinetic equations are replaced by kinetic ones. The criteria for applicability of the kinetic approach are discussed. Since the solutions are linear combinations of exponents, both the exponents and the preexponential factors were taken into account. As an example Au diffusion into a Si film was studied taking into account both the dissociative and the kickout mechanisms. To analyze thin-film diffusion, in addition to terms describing the diffusion transport in crystals of infinite sizes, thin-film surfaces were considered as a substantial source and/or sink of point defects. The different diffusion mechanisms and regimes and the conditions of transition from one mechanism and/or regime to another were found. Expressions were obtained for the critical sample thicknesses, dislocation density, swirl and vacancy cluster density, and temperatures, when transitions of the diffusion transport mechanisms and regimes occur. Possible areas for existence of these transport regimes were determined. Quantitative criteria of the critical values of temperature, dislocation density and thin film thickness for transitions of the Au-Si diffusion transport mechanisms were obtained. For fairly long times the results obtained in the kinetic approach coincide with those of the diffusion-kinetic one but the set of pure kinetic equations is much simpler to solve. This implies that the kinetic approach is a valuable approximation to multiple pathway diffusion with traps.
Clinical efficacy and safety of indapamide in essential hypertension

Indapamide, a new methylindoline diuretic that appears to act on the distal renal tubules, is also reported to reduce vascular smooth muscle vasopressor reactivity and possibly to have a calcium-antagonist effect. Since 1973, sixteen studies by a number of European investigators who treated 301 patients with indapamide have revealed satisfactory control in 53% of patients with mild hypertension (standing diastolic pressures less than 90 mm Hg) and in 43% of patients with moderate hypertension when the drug was used without other agents. Multiple American clinical trials of indapamide in hypertension have been conducted, including double-blind, placebo-controlled protocols and trials comparing indapamide with traditional diuretic agents. A cooperative, double-blind, 40-week study compared antihypertensive response to indapamide, 2.5 mg and 5 mg daily, with response to hydrochlorothiazide, 50 mg daily, in the treatment of mild to moderate hypertension. Pretreatment diastolic blood pressures averaged 101 mm Hg. At 40 weeks of treatment, indapamide, 2.5 mg daily, had produced a fall in diastolic pressure of 15 mm Hg; indapamide, 5 mg daily, a reduction of 16 mm Hg; and hydrochlorothiazide, 50 mg daily, a fall of 15 mm Hg. Seventy-five percent of patients taking 2.5 mg of indapamide daily and 88% of those taking 5 mg achieved satisfactory blood pressure reduction. Hypokalemia may occur with indapamide but is a minor problem and seldom necessitates potassium supplementation. Serum uric acid increases were observed in only a few subjects, and clinical side effects are infrequent and mild. Indapamide is a useful antihypertensive agent with good patient tolerance in mild or moderate hypertension and may offer advantages over traditional diuretics in view of its possible vasodilator and calcium-antagonist properties, once-a-day dosage, and good therapeutic effect with prolonged usage.
Hepatic binding proteins translocating azo dye carcinogen metabolites from cytoplasm into nucleus in rats.

When liver cytosol prepared from rats administered [14C]-30-Methyl-N,N-dimethyl-4-aminoazobenzene was subjected to Sephadex gel chromatography, four peaks of radioactivity containing proteins (Peak-I–IV) and one peak devoid of protein (Peak-V) were obtained. Translocation of azo dye metabolites from these various cytosolic fractions into nucleus was studied in an in vitro system and a maximum of about 10% of the radioactivity associated with a particular cytosolic fraction (Peak-II) could translocate into the nuclei. Radioactivity (%) translocated did not increase upon addition of excess nuclei. Passage of this protein fraction through an immobilized protease column reduced the azo dye metabolite translocation by 65%, concomitant with the degradation of proteins. Translocation was not observed with protein-free metabolites extracted from this cytosolic fraction; addition of proteins corresponding to peak-II from normal rat liver cytosol significantly restored the metabolite translocation. This observation suggests that specific cytosolic proteins are involved in the translocation of azo dye carcinogen metabolites from liver cytoplasm into the nucleus. When the liver cytosolic proteins corresponding to this fraction (Peak-II) were iodinated with 125I-iodine and incubated with purified nuclei, translocation of three specific proteins into nucleus was observed as seen by SDS–PAGE and fluorography of nuclear proteins. Covalent binding of azo dye metabolites to DNA was not observed when cytosolic peak-II fraction containing azo dye metabolites was incubated with isolated liver DNA instead of liver nuclei. This suggests that the interaction of azo dye metabolites with nuclear macromolecules necessitate further prior processing which actually may occur in the nucleus.
On Agency and Structure: Pierre Bourdieu and Jean-Claude Passeron's Theory of Symbolic Violence

(1984). On Agency and Structure: Pierre Bourdieu and Jean-Claude Passeron's Theory of Symbolic Violence. Curriculum Inquiry: Vol. 14, No. 2, pp. 151-163.
Process weldability and thermal modeling on INCOLOY 800: comparsion between TIG process without a filler wire and laser process

A comparison of TIG welding and laser welding of INCOLOY 800 is presented under two different aspects: weld pool sensitivity to minor elements and modelling of stresses and temperatures distribution. For TIG welding, welding parameters have to be adjusted when changing of INCOLOY 800 master melt. It appeared that laser welding did not depend on the material chemistry and gave a good reproducibility of the results, whatever is the mater melt, with the same parameters. Thermal modelling was developed for a tube-tubesheet configuration. TIG modelling showed a stress localization for several chemistries, which indicated a risk of cracking at the root of the weld. The modelling showed how it is related both to the temperature of the base material close to the molten pool, and the duration of the process. For the INCOLOY 800, the longer the temperature is in the 800-1000 degree(s)C range, the higher the risk of cracking exists. For laser welding, the risk is much lower, because the process is incomparably faster.
Differential effects of modification of membrane cholesterol and sphingolipids on the conformation, function, and trafficking of the G protein-coupled cholecystokinin receptor.

The lipid microenvironment of receptors can influence their conformation, function, and regulation. Cholecystokinin (CCK)-stimulated signaling is abnormal in some forms of hyperlipidemia, suggesting the possibility of unique sensitivity to its lipid environment. Here we examined the influence of cholesterol and sphingolipids on CCK receptors in model Chinese hamster ovary cell systems having lipid levels modified. Cholesterol was modulated chemically or metabolically, and sphingolipids were modulated using a temperature-sensitive cell line (SPB-1). Receptor conformation was probed with a fluorescent full agonist ligand, Alexa 488-conjugated Gly-[Nle28,31]CCK-(26–33), shown previously to decrease in anisotropy and lifetime when occupying a receptor in the active conformation (Harikumar, K. G., Pinon, D. L., Wessels, W. S., Prendergast, F. G., and Miller, L. J. (2002) J. Biol. Chem. 277, 18552–18560). Anisotropy and lifetime of this probe were increased and prolonged with cholesterol enrichment, and decreased and shortened with depletion of cholesterol or sphingolipids. The increase in these parameters with cholesterol enrichment may reflect change in CCK receptor conformation toward its inactive, uncoupled state. Indeed, cholesterol enrichment resulted in nonproductive agonist ligand binding, with affinity of binding higher than normal and calcium signaling in response to this reduced. In cholesterol- and sphingolipid-depleted states, the receptor moved into conformations that were less than optimal. With cholesterol depletion, both ligand binding and signaling were decreased, yet internalization and trafficking were unperturbed. With sphingolipid depletion, ligand binding and signaling were normal, but internalization and trafficking were markedly inhibited. Of note, normal transferrin receptor trafficking through the same clathrin-dependent pathway was maintained under these conditions. Thus, lipid microenvironment of the CCK receptor is particularly important, with different lipids having distinct effects.
Phenotype and functionality of CD4+ and CD8+ T cells in the upper reproductive tract of healthy premenopausal women.

Problem The goal of this study was to investigate the phenotype and functional responsiveness of CD4+ and CD8+ T-cells in the upper reproductive tract of healthy premenopausal women. The lower reproductive tract is frequently studied as a site of sexually transmitted infections; however, the upper tract may also be a portal of entry and dissemination for pathogens, including HIV-1.
Twice-daily reirradiation for recurrent and second primary head-and-neck cancer with gemcitabine, paclitaxel, and 5-fluorouracil chemotherapy

Purpose We previously demonstrated the efficacy of concurrent gemcitabine, paclitaxel, and 5-fluorouracil in conjunction with twice-daily (1.5-Gy) radiotherapy delivered on alternating weeks (TFGX 2 ) in locally advanced head-and-neck cancer. Here, we report the clinical outcome and late toxicity of TFGX 2 in a subset of patients previously irradiated to the head and neck. Methods and materials Twenty-nine previously irradiated patients, presenting with recurrent or second primary head-and-neck cancer, underwent TFGX 2 . Twelve patients underwent attempted surgical resection before chemoradiotherapy, 10 of whom were left with no measurable disease. Patients with measurable disease received a median radiation dose of 72 Gy; those with no measurable disease received a median dose of 61 Gy. The cumulative dose ranged from 74.4 to 156.4 Gy (mean, 125.7 Gy; median, 131.0 Gy). Results The median follow-up was 19.1 months (50.9 months for living patients). The 5-year overall survival rate was 34.5%, and the locoregional control rate was 54.5%. In patients with measurable disease at treatment, the 5-year overall survival and locoregional control rate was 26.3% and 45.1%, respectively, compared with 50.0% ( p = 0.14) and 70% ( p = 0.31), respectively, for those with no measurable disease. Measurable disease and radiation dose were highly statistically significant for overall survival and locoregional control on multivariate analysis. Of 14 patients assessable for late toxicity, 3 developed Grade 4-5, 8 Grade 2-3, and 3 Grade 0-1 toxicity. Conclusion Aggressive reirradiation with chemotherapy in locally advanced head-and-neck cancer provides a chance for long-term cure at the expense of toxicity. Attempted surgical resection before chemoradiotherapy improved disease control and survival.
DISCOVERY OF THE ZEEMAN EFFECT IN THE 44 GHz CLASS I METHANOL (CH3OH) MASER LINE

We report the discovery of the Zeeman effect in the 44?GHz Class I methanol (CH3OH) maser line. The observations were carried out with 22 antennas of the Expanded Very Large Array toward a star-forming region in OMC-2. Based on our adopted Zeeman splitting factor of z = 1.0 Hz mG-1, we detect a line-of-sight magnetic field of 18.4 ? 1.1 mG toward this source. Since such 44?GHz CH3OH masers arise from shocks in the outflows of star-forming regions, we can relate our measurement of the post-shock magnetic field to field strengths indicated by species tracing pre-shock regions, and thus characterize the large-scale magnetic field. Moreover, since Class I masers trace regions more remote from the star-forming core than Class II masers, and possibly earlier phases, magnetic fields detected in 6.7?GHz Class II and 36 and 44?GHz Class I methanol maser lines together offer the potential of providing a more complete picture of the magnetic field. This motivates further observations at high angular resolution to find the positional relationships between Class I and Class II masers, and masers at various frequencies within each category. In particular, CH3OH masers are widespread in high- as well as intermediate-mass star-forming regions, and our discovery provides a new method of studying the magnetic field in such regions, by observing small physical scales that are not accessible by any other lines.
Distributed Genetic Algorithm Model on Network of Personal Computers

Despite recent advances in desktop computing power, certain civil engineering problems continue to depend on supercomputers and powerful workstations. Although supercomputers and workstations helped in field testing complicated mathematical models, there appears to be a significant gap in widespread technology transfer to the industry. The sluggish progress in transfer of technology to the industry may be attributed to the inability to implement these models on PCs coupled with high costs associated with supercomputers. The paper reports results from an exploratory research that implemented a complicated optimization model based on a distributed genetic algorithm on a network of PCs. PCs that formed the network were hardwired using 16bit 10Base-T Ethernet cards and were made accessible using Peer-to-Peer networking capability, which is a built-in feature of Microsoft Windows 95/NT operating system. The inherent parallelism associated with genetic algorithms coupled with relatively small data exchange between the computers resulted in a significant reduction of computational time. The proposed generalized optimization framework, which can be adopted to model several water resources related problems, is expected to accelerate the transfer of technology to the industry.
Acceleration of skin regeneration from cultured epithelial autografts by transplantation to homograft dermis

Cultured epithelial autografts transplanted to homograft dermis were analyzed histopathologically from 9 days to 2.25 years after grafting and compared with cultured epithelial autografts transplanted to wound beds devoid of homograft dermis in the same patient. The results suggested that grafting to a dermal substrate accelerates biologic events in skin regeneration from cultured epithelial autografts. Both rete ridge development and normalization of the epidermal keratin program from a "hyperproliferative" to a normal pattern occurred months sooner in the cultured epithelial autografts placed on a dermal matrix. Regeneration of anchoring fibrils was also accelerated. Neither repopulation by Langerhans cells nor repigmentation appeared to be altered significantly by grafting to dermal tissue. By special stain, the elastin network of the allograft dermis could still be visualized at 2.25 years, indicating long-term persistence of the homograft matrix. By clinical assessment the rate of successful engraftment ("take rate") of cultured epithelial autografts grafted to allodermis was estimated to be about 95%, and long-term durability was excellent.
The photophysics of Ni(II) meso-tetraphenylbenzoporphyrin: A combined theoretical and experimental investigation

Abstract A combined theoretical and kinetic spectrometric investigation of Ni(II)-tetraphenyl tetrabenzoporphyrin (NiTPTBP) has demonstrated that photo-excitation into the B band (400 nm) of the ground state absorption spectrum rapidly generates the compound in its Q state. The intriguing time dependence of stimulated emission generated from the Q state implies that this state is populated via two (or more) radiationless channels, one is very rapid (
Imaging of Oxidation-Specific Epitopes with Targeted Nanoparticles to Detect High-Risk Atherosclerotic Lesions: Progress and Future Directions

Oxidation-specific epitopes (OSE) within developing atherosclerotic lesions are key antigens that drive innate and adaptive immune responses in atherosclerosis, leading to chronic inflammation. Oxidized phospholipids and malondialdehyde-lysine epitopes are well-characterized OSE present in human atherosclerotic lesions, particularly in pathologically defined vulnerable plaques. Using murine and human OSE-specific antibodies as targeting agents, we have developed radionuclide and magnetic resonance based nanoparticles, containing gadolinium, manganese or lipid-coated ultrasmall superparamagnetic iron oxide, to non-invasively image OSE within experimental atherosclerotic lesions. These methods quantitate plaque burden, allow detection of lesion progression and regression, plaque stabilization, and accumulation of OSE within macrophage-rich areas of the artery wall, suggesting they detect the most active lesions. Future studies will focus on using "natural" antibodies, lipopeptides, and mimotopes for imaging applications. These approaches should enhance the clinical translation of this technique to image, monitor, evaluate efficacy of novel therapeutic agents, and guide optimal therapy of high-risk atherosclerotic lesions.
DIFFERENTIAL INEQUALITIES FOR LIAPUNOV FUNCTIONS

This chapter discusses differential inequalities for Liapunov functions. It discusses a system of ordinary differential equations x ' = f ( t , x ) where f: [0, ∞) × R n → R n is continuous and it is supposed that there is a function V : [0, ∞) × R n → [0, ∞) that is continuous, locally Lipschitz in x , and satisfies V' 1 ( t , x ) ≤ 0. The discusses differential inequalities relating V ' and x ' = f ( t , x ) to conclude that solutions of x ' = f ( t , x ) are continuable, bounded, or approach certain limit sets. It is noticed that when V is autonomous and differentiable, then V ' 1 = | grad V | f | cos θ with θ being the angle between grad V and f .
The Tourist Gaze in Travel Documentaries: The Case of Cannibal Tours

When tourists go sightseeing, they see more than just sights. This study examined the diverse gazes in the context of tourism from two existing frameworks—the Foucauldian and Lacanian notion of the gaze. A qualitative case study on the documentary Cannibal Tours (1988) was conducted to unravel the complexities of the tourist gaze and validate the concept of the gaze within theoretical frameworks. This film provided ample visual evidence of the gaze in tourism settings, illustrating the existence and mechanism of the tourist gaze, the local gaze, and the second gaze. Analysis of this film generated a better understanding of the structure and psychology of the gaze within the dynamic interactions between tourists and locals.
Attention, Working Memory, and Grammaticality Judgment in Typical Young Adults.

Purpose To examine resource allocation and sentence processing, this study examined the effects of auditory distraction on grammaticality judgment (GJ) of sentences varied by semantics (reversibili...
The Rate of Convergence for the Decomposition Method

Abstract We prove the convergence of approximations by the decomposition method for semi-linear evolution equations with a quadratic nonlinearity. We also obtain the rate of convergence and a computable error bound for the approximation in the case one of the eigenvalues is a negative integer. The method can easily be generalized for quadratic nonlinearities appearing in the well-known K.P.P and K.dV equations.
EVALUATION OF THE IMMUNOMODULATORY EFFECTS OF THE MACROLIDE ANTIBIOTIC, CLARITHROMYCIN, IN FEMALE B6C3F1 MICE: A 28-DAY ORAL GAVAGE STUDY

The macrolide antibiotic, clarithromycin, is used extensively to treat bacterial infections associated with pneumonia, duodenal ulcers, and the advanced stages of human immunodeficiency viral (HIV) infection. In addition to its antimicrobial properties, several studies have indicated that clarithromycin also has anti-inflammatory and immunomodulatory properties. In this study, clarithromycin's immunomodulatory properties were evaluated using female B6C3F1 mice and a panel of immune assays that were designed to evaluate potential changes in innate, and acquired cellular and humoral immune responses. Female B6C3F1 mice were treated daily by gavage with clarithromycin (0, 125, 250, and 500 mg/kg) for 28 days then evaluated for immunomodulation. Minimal immunological changes were observed after 28 days of treatment. A slight increase in the number of spleen antibody-forming cells was observed at the 250 mg/kg treatment level, but not at other doses. Serum IgM levels were unaffected by the clarithromycin treatment. A significant increase in the number of splenic macrophages was also observed in mice treated with 125 mg/kg of clarithromycin, but this increase was not observed at the other treatment levels. Innate and cell-mediated immunity, as measured by natural killer cell activity, and mixed leukocyte and cytotoxic T cell response, respectively, were unchanged following treatment with clarithromycin. These results suggest that the immune system is not a target for clarithromycin at doses of 500 mg/kg or below.
I. A new determination of e, N, and related constants

(1917). I. A new determination of e, N, and related constants. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science: Vol. 34, No. 199, pp. 1-30.
Studies of silicon photoelectrochemical cells under high injection conditions

The behavior of Si/CH3OH-dimethylferrocene+/0 junctions has been investigated under high injection conditions. Open circuit voltages of (626±5) mV were obtained at short circuit photocurrent densities of 20 mA/cm^2 for samples with an n + -diffused back region, point contacts on the back surface, and with a base of thickness 390 µm and a 1 ms hole lifetime. The diode quality factor and recombination current density were 1.8±0.1 and (2.6±1.5)×10–8 A/cm^2, respectively. These data are consistent with recombination dominated by the base and back contact regions, and not at the Si/CH3OH interface.
Taking Egoism Seriously

Though utilitarianism is far from being universally accepted in the philosophical community, it is taken seriously and treated respectfully. Its critics do not dismiss it out of hand; they do not misrepresent it; they do not belittle or disparage its proponents. They allow the theory to be articulated, developed, and defended from criticism, even if they go on to reject the modified versions. Ethical egoism, a longstanding rival of utilitarianism, is treated very differently. It is said to be “refuted” by arguments of a sort that apply equally well to utilitarianism. It is said to be “unprovable,” when many of the greatest utilitarians themselves, such as Jeremy Bentham (1748–1832), John Stuart Mill (1806–1873), and Henry Sidgwick (1838–1900), admitted that no normative ethical theory, including their own, is provable. Critics of ethical egoism seldom discuss the various theoretical moves that utilitarians are routinely allowed to make, such as (1) fighting the facts, (2) transforming the theory from “act utilitarianism” to “rule utilitarianism,” and (3) biting the bullet. This essay argues that every defensive move made by utilitarians can be made, with equal vigor (if not also plausibility), by ethical egoists. The conclusion is that ethical egoism deserves to be taken more seriously than it is.
Insertion Reactions of Tantalum(V) Carborane Alkyl and Aryl Complexes with Nitriles and Isonitriles. Thermal and Photochemical Isomerization of η2-Iminoacyl Isomers1

Tantalum carborane complexes (Et2C2B4H4)CpTaR2 (R = Me, Ph) undergo insertion reactions with nitriles and isonitriles under conditions that differ from formally isoelectronic metallocene compounds of group 4 metals. The dimethyltantalum system requires UV−vis irradiation, whereas the diphenyltantalum complex generally reacts at elevated temperatures. Although insertions of isonitriles into metal−alkyl bonds have been reported in a wide variety of cases, there are very few examples of stable isomeric η2-iminoacyl intermediates that can be isolated and completely converted from one form into the other. Two such cases are reported here, including the X-ray crystallographic analysis of both isomers of (Et2C2B4H4)CpTaCH3(η2-C,N-C{N-t-Bu}CH3) (5a,5b) and one isomer of (Et2C2B4H4)CpTaCH3(η2-C,N-C{N(2,6-Me2C6H3)}C6H5) (7a). Photochemical isomerization of 7a, followed by exposure to an additional equivalent of isocyanide, resulted in a novel cage-insertion reaction to give [(Et2C2B4H3(C6H5)(CHN(2,6-Me2C6H3))]CpTa(...
Monitoring changes in endogenous fluorophores through quantitative FLIM imaging in live cells

Changes in energy metabolism, mitochondrial functions and of reactive oxygen species are often supposed to induce alterations in cellular activity. The major intracellular endogenous fluorophores are reduced nicotinamide adenine dinucleotide (NADH) and dinucleotide phosphate (NADPH), riboflavin's, and tryptophan present inside biological tissue and they can be used to image tissue architecture without any exogenous probe. Their fluorescence can be excited by multi-photon microscopy using NIR laser wavelengths [1,2,5,6]. Using FLIM imaging the lifetime of tryptophan and NADH were monitored in cells with and without addition of glucose in the medium. The lifetime data were collected and further using the ANOVA (refer table 2) of the lifetime of free NADH, bound NADH and Tryptophan, we found on applying the null hypothesis for the P-value > 0.05, there is a significant difference between the lifetimes of bound NADH and Tryptophan from control to glucose treated cells, however, free NADH, shown to be not significant change between the control and glucose treated cells. The tryptophan puzzle comes closer and closer to a solution. The ultimate evidence supporting the existence of FRET between Tryptophan and NADH in live cells slowly could come from lifetime measurements of tryptophan in proteins and bound NADH within live cells.
Evaluation of canal cleanliness and smear layer removal after the use of the Quantec-E irrigation system and syringe: a comparative scanning electron microscope study.

Abstract Objective The purpose of this study was to evaluate canal cleanliness and smear layer removal after use of the Quantec-E irrigation system and to compare the system with traditional irrigation. Study design Forty anterior teeth were randomly assigned to 4 groups. Group A consisted of 15 teeth that were instrumented with .12, .10, .08, .06 and .04 tapered rotaries while simultaneously irrigated via the Quantec-E irrigation pump with 12 mL of 5.25% NaOCl, followed by 6 mL EDTA 17% in crown-down fashion, with a final flush with 4 mL 5.25% NaOCl. Group B consisted of 15 teeth that were instrumented with the same instrument sequence, and irrigated with the same volumes via traditional needle and syringe. Group C consisted of 5 teeth that were sectioned and examined under a scanning electron microscope (SEM) without any instrumentation and served as a negative control. Group D consisted of 5 teeth that were instrumented dry, without any irrigation, and served as a positive control. All teeth were sectioned buccolingually and examined with SEM at 700× magnification in the apical, middle, and coronal portions of the canals. Analysis of SEM images was performed by 5 independent examiners using a 4-point scoring system. Results Irrigation with the Quantec-E irrigation pump resulted in cleaner canal walls, less debris, and more complete removal of the smear layer within the coronal one third, when compared with syringe irrigation. However, no difference was observed in the middle and apical one thirds of the root canal. Conclusion There was no significant difference between the 2 irrigation systems.
Alterations of DNA methylation by glutathione depletion

One of the most consistent findings in cancer cells is an overall decrease of 5-methylcytosine content in DNA. The causes that lead to this alteration are not known. We have shown in a recent study that the methyl-donor, methionine (Met), can easily be depleted and that O- and S-methylation can be impaired in response to glutathione (GSH) depletion. This is because mammalian cells are capable of resynthesizing GSH after GSH is depleted, and GSH turnover occurs at the expense of Met. An extensive utilization of Met for the resynthesis of GSH causes Met depletion and impairment in methylation. In the present study we now demonstrate that GSH depletion has a significant impact on DNA methylation. An i.p. dose of a model GSH-depleting hepatotoxin, bromobenzene (BB), caused a progressive impairment in genomic DNA methylation in the Syrian hamster. The administration of a single i.p. dose of Met labeled with [14CH3]Met to BB-treated hamsters at either 1, 3, 5.5 or 9 h after BB resulted in an increase of methyl-group incorporation into liver genomic DNA at 24 h after BB. With respect to the time points chosen for Met administration, methyl-group incorporation found in the BB + Met groups were 1-, 2-, 4- and 12-fold of the controls that received only Met. We further employed an in vitro methylation assay using specific bacterial SssI CpG methylase as the catalyzing enzyme to demonstrate that BB caused a progressive increase of unmethylated CpG sites in genomic DNA. Interestingly, the time response curve of global DNA methylation in vitro showed an identical pattern to that observed in the in vivo experiment. The results provide strong evidence that GSH-depleting agents significantly impair cytosine methylation. Thus, alterations in gene expression could result from a high dose and/or prolonged exposure to GSH-depleting agents, e.g. medications, chemotherapeutic agents and environmental toxins.
Ecdysis Control Sheds Another Layer

The process by which a butterfly emerges from a chrysalis, called ecdysis, has been thought to be controlled by eclosion hormone. J. Truman discusses the discovery of a new insect hormone, reported in this issue of Science by hacek Zithacek nan et al. (p. 88), that can also trigger ecdysis—MasETH. The two hormones seem to act sequentially.
The multilingual and multi-orthographic Taiwan-based Internet: Creative uses of writing systems on college-affiliated BBSs

This study investigates creative uses of writing systems on the electronic bulletin boards (BBSs) of two college student organizations in Taipei, Taiwan. Data were collected from postings on bulletin boards and semi-structured interviews with members of the student organizations, and analyzed using qualitative and ethnographic methods. Four popular creative uses of writing systems are identified and discussed: the rendering in Chinese characters of the sounds of English, Taiwanese, and Taiwanese-accented Mandarin, and the recycling of a transliteration alphabet used in elementary education. It is argued that these practices are enabled by the written nature of the Internet, the orthographic systems available in the society, and the multilingual situation in Taiwan, and that the everyday meanings associated with the writing systems and languages are appropriated and reproduced through online practice, resulting in a unique mode of communication in its own right.
Well‐defined glycopolymer amphiphiles for liquid and supercritical carbon dioxide applications

Well-defined D-glucose-containing glycopolymers, poly(3-O-methacryloyl-1,2:5,6-di-O-isopropylidene-D-glucofuranose) (PMAIpGlc), and diblock copolymers of PMAIpGlc with poly(1,1-dihydroperfluorooctyl methacrylate) (PFOMA) were synthesized by living anionic polymerization in THF at -78 °C with 1,1-diphenylhexyllithium in the presence of lithium chloride. The resulting polymers were found to possess predictable molecular weights and very narrow molecular weight distributions (MWD, M u /M n ≤ 1.16). Removal of the acetal protective groups from the protected glycopolymer block copolymer was carried out using 90% trifluoroacetic acid at room temperature, yielding a hydrophilic block copolymer with pendant glucose moieties. Both protected (lipophilic/CO 2 -philic) and deprotected (hydrophilic/CO 2 -philic) fluorocopolymers were proved to be CO 2 amphiphiles. Their solubility in CO 2 was heavily influenced by the amphiphilic structure, such as the copolymer compositions and the polarities of sugar block. Light-scattering studies showed that, after removal of the protective groups, the deprotected block copolymer formed aggregate structures in liquid CO 2 with an average micellar size of 27 nm.
Solubility of Guaifenesin in the Presence of Common Pharmaceutical Additives

The aqueous solubility of guaifenesin, a highly water‐soluble drug, in the presence of salts, sugars, and cosolvents was determined at 25°C and 40°C. The solubility of drug at both temperatures was...
Factors associated with serum retinol, α-tocopherol, carotenoids, and selenium in Hispanics with problems of HIV, chronic hepatitis C, and drug use

The effects of hepatitis and drug use on nutritional problems in HIV infection have rarely been examined despite the importance of drug use in the global HIV pandemic. We examined the effects of HIV, hepatitis C, and drug use on serum micronutrients in 300 US Hispanic adults. Chronic hepatitis C infection was associated with lower serum retinol (-8.2 microg/dl, P < 0.0001), alpha-tocopherol (-0.10 ln microg/dl, P = 0.024), and carotenoids (-19.8 microg/dl, P < 0.0001). HIV infection was associated with lower selenium (-6.1 microg/l, P = 0.028). Elevated triglycerides in HIV infection were associated with higher serum retinol and alpha-tocopherol. Drug use was not independently associated with micronutrient alterations. We conclude that hepatitis C is an important determinant of low serum micronutrients, and should be considered in any nutritional assessment of HIV infected populations. As the safety of micronutrient supplementation is not established, policy for appropriate HIV clinical care should distinguish between populations with and without hepatitis coinfection.
Analysis of the National Institute of Neurological Disorders and Stroke Tissue Plasminogen Activator Studies Following European Cooperative Acute Stroke Study III Patient Selection Criteria

Background In 1995 two studies by the National Institute of Neurological Disorders and Stroke (NINDS) proved that intravenous tissue plasminogen activator (t-PA) was superior to placebo in patients with stroke of less than 3 hours' duration. The recently published European Cooperative Acute Stroke Study (ECASS) III introduced new patient selection criteria and treatment between 3 and 4.5 hours. Using these criteria, t-PA was shown effective at the later time window. Both analyses used the 3-month modified Rankin scale (mRS) score as main primary outcome. We sought to study the effect of applying the ECASS III selection criteria to the original NINDS cohort. Methods We analyzed the subgroup of patients from NINDS sample who matched the ECASSS III criteria. We examined 3-month outcomes adjusted and unadjusted for confounding factors. Results The NINDS t-PA study included 624 patients. A total of 200 in the t-PA-treated group and 199 in the placebo group were selected after applying ECASS III criteria. Of these selected patients, 52% in the t-PA group versus 31% had mRS score of 0 or 1 at 3 months (P Conclusion Using the ECASS III criteria in patients treated in less than 3 hours, 52% of t-PA-treated patients had a favorable outcome at 3 months.
Sensory evaluation of broiled and grilled bison patties by trained panelists

Sensory characteristics of broiled and grilled patties from grain-fed bison were evaluated by a 13-member trained sensory panel. Ground patties (approximately 113 g, 12.2 cm diameter, 0.9 cm thick) from 6 grinding dates were broiled (260C) or grilled (163C) to 71C internal temperature. Cooking time was significantly shorter (p Les boulettes de viande de bison eleve aux cereales sont evaluees par un jury de 13 experts sensoriels. La viande est rotie (260°C) ou grillee (163°C), la temperature interne etant de 71°C. La flaveur et les qualites aromatiques sont equivalentes pour les 2 types de cuisson, les couleurs et la tendrete sont variables.
The Molecular Autopsy: Should the Evaluation Continue After the Funeral?

Sudden cardiac death (SCD) is one of the most common causes of death in developed countries, with most SCDs involving the elderly, and structural heart disease evident at autopsy. Each year, however, thousands of sudden deaths involving individuals younger than 35 years of age remain unexplained after a comprehensive medicolegal investigation that includes an autopsy. In fact, several epidemiologic studies have estimated that at least 3% and up to 53% of sudden deaths involving previously healthy children, adolescents, and young adults show no morphologic abnormalities identifiable at autopsy. Cardiac channelopathies associated with structurally normal hearts such as long QT syndrome (LQTS), catecholaminergic polymorphic ventricular tachycardia (CPVT), and Brugada syndrome (BrS) yield no evidence to be found at autopsy, leaving coroners, medical examiners, and forensic pathologists only to speculate that a lethal arrhythmia might lie at the heart of a sudden unexplained death (SUD). In cases of autopsy-negative SUD, continued investigation through either a cardiologic and genetic evaluation of first- or second-degree relatives or a molecular autopsy may elucidate the underlying mechanism contributing to the sudden death and allow for identification of living family members with the pathogenic substrate that renders them vulnerable, with an increased risk for cardiac events including syncope, cardiac arrest, and sudden death.
A tale of two nets: studies of wirelength progression in physical design

At every stage in physical design, engineers are faced with many different objectives and tools to develop, optimize, and evaluate their design. Each choice of a tool or an objective to optimize can potentially lead to a completely different final physically designed circuit. Furthermore, some of the objectives optimized by the tools are not necessarily the best or right objectives, but rather compromised objectives; for example, placers optimize the half-perimeter wirelength rather than the routed wirelength. The contributions of this paper are twofold. First, we define and use a metric to measure the consistency of optimizing wirelength during the different stages of physical design. Our main technique is based on tracing the relative lengths of two nets - or more accurately pairs of nets - as they progress through the physical design flow. Second, we propose a simple method to quantify the similarity between the results of different tools. Our empirical results point out to the physical design stages where vulnerability can occur from optimizing compromised objectives.
Activation of pyruvate dehydrogenase complex (PDC) of rat heart mitochondria by glyburide

The effects of the second generation sulfonylurea, glyburide, on the pyruvate dehydrogenase multienzyme complex (PDC) of rat myocardial tissue were examined using rat ventricular slices and isolated mitochondria. Therapeutic concentrations (10(-7) to 10(-6)M) of glyburide produced a 30% increase in the decarboxylation of [1(-14)C] pyruvate by the PDC of ventricular tissue. Addition of glyburide to intact rat heart mitochondria stimulated activity of the PDC in a time- and concentration-dependent manner. Half-maximal stimulation of the enzyme occurred with 6 X 10(-5)M glyburide and maximal activation of the enzyme was achieved with 1 X 10(-4)M glyburide. At the height of stimulation, PDC activities were 6-fold greater than those observed under control conditions with succinate alone. When mitochondria were disrupted by sonication or freeze-thawing, glyburide produced no stimulation of pyruvate decarboxylation. We conclude that glyburide directly stimulates the decarboxylation of pyruvate by the PDC of the myocardium. Furthermore, the presence of intact mitochondria is necessary for the stimulatory action of glyburide on the PDC.
Exploring the Social Foundations of Human Resource Development: A Theoretical Framework for Research and Practice

An important area of continuing development in human resource development (HRD) concerns the foundational theories that underpin research and practice in the field. This article explores some of the philosophical and theoretical foundations of the social realm related to HRD. As such, it provides a perspective for framing HRD research and practice from the view that social forces arbitrate the thoughts and behaviors of people. This perspective begins with philosophical questions on the nature of social science and continues with an overview of key concepts and theories drawn from sociology and social psychology. For some, social science is qualitatively different from natural science and therefore requires different methods for study, as well as different theoretical frames. The intent here is to offer a framework for approaching HRD from the perspective of the social realm.
Sternberg's Additive Factor Method and Underlying Psychological Processes: Some Theoretical Considerations

Sternberg's additive factor method is generally accepted by experimental psychologists as a decisive method for the decomposition of the reaction time process into stages. It is presented as an alternative for Bonders' subtraction method and the so-called structuralist or model approach. One of the purposes of this article is to demonstrate the theoretical differences between the functionalist or Sternbergian approach to reaction time and the structuralist or model approach. The two approaches are evaluated relative to their fertility in contributing to the understanding of the processes involved in human information processing and the systematic cumulation of knowledge regarding these processes. The main goal of this article is to discuss some problems related to the assumptions used in the additive factor method. It is shown that the relation between the mean reaction time for one subject and the mean reaction time over subjects, which is generally used as the dependent variable in the analysis of variance, depends on the specific distribution of reaction times within the stages. It is pointed out that the interpretation of factor effects resulting from the analysis of variance is not clear. In addition, it is shown that the additive factor method cannot be used to identify or estimate the number of stages in the reaction time process. The use of reaction time (RT) experiments in experimental psychology goes back as far as 1850. The RT experiment was introduced by Helmholtz (1850) as a method for measuring the speed of nerve conduction. However, the use of RT experiments as a paradigm to study mental processes originated from the work of the Dutch physiologist Donders. Donders (1868/1969) proposed a theory for reaction time based on the assumption that RT is in fact a composite score, representing a reaction, a discrimination , and a choice process. The debate that arose from the work of Donders still centers around two major issues.
MECHANICAL CONTROLS ON THE SPATIAL DENSITY OF OPENING-MODE FRACTURE NETWORKS

Understanding the controls on fracture density is critical to interpreting the geologic evolution, permeability, and mechanical properties of jointed rock. Analyses of fracture trace maps and seismic inversions reveal that near-surface fracture densities are generally less than ∼1–2 over a range in scale of 14 orders of magnitude. The observed densities are approximately an order of magnitude greater than the range typical of deeper (>500 m) formations and may indicate that surficial controls on fracture growth are different than those at depth. The development of greater densities at the surface may be limited by the significant decrease in effective elastic stiffness associated with fracture densities near unity. As fracture densities approach 1.0, additional strain accommodated by the fractures decreases the driving tension, limiting further fracture growth.
Transmission Electron Microscopy of Shape-Controlled Nanocrystals and Their Assemblies

The physical and chemical properties of nanophase materials rely on their crystal and surface structures. Transmission electron microscopy (TEM) is a powerful and unique technique for structure characterization. The most important application of TEM is the atomic-resolution real-space imaging of nanoparticles. This article introduces the fundamentals of TEM and its applications in structural determination of shape-controlled nanocrystals and their assemblies. By forming a nanometer size electron probe, TEM is unique in identifying and quantifying the chemical and electronic structure of individual nanocrystals. Electron energy-loss spectroscopy analysis of the solid-state effects and mapping the valence states are even more attractive. In situ TEM is demonstrated for characterizing and measuring the thermodynamic, electric, and mechanical properties of individual nanostructures, from which the structure−property relationship can be registered with a specific nanoparticle/structure.
Frequency of Unrecognized Bordetella pertussis Infections in Adults

To investigate the frequency of unrecognized Bordetella pertussis infections in adults, we performed IgA and IgG ELISA antibody studies with four B. pertussis antigens-i.e., lymphocytosis-promoting factor, filamentous hemagglutinin, pertactin, and fimbriae-2-in 51 health care workers from whom six consecutive yearly serum samples (from 1984 to 1989) were available. Overall, 90% of the subjects had a significant increase in antibody (IgA or IgG) to one or more antigens between 2 consecutive years during the 5-year study period ; 55% of subjects had evidence of two infections, 17% had three infections, and 4% had four infections. Infections occurred in all study years, with the following rates : 1984-1985, 32% ; 1985-1986, 24% ; 1986-1987, 40% ; 1987-1988, 29% ; and 1988-1989, 43% (P=.12). Some antibody rises may have been due to responses to cross-reacting antigens (Bordetella parapertussis, nontypable Haemophilus influenzae), but overall these data suggest that B. pertussis infections in adults are common, endemic, and usually unrecognized.