cssi/SciSciGPT-SciSciNet huggingface dataset:
An Acid Rain Study in the Washington, D.C. Area

Abstract A field study in the Washington, D.C. area explored the impact of urban emissions and mesoscale meteorology on precipitation chemistry. The study was a follow-up to an earlier, considerably more industrialized, study in the Philadelphia area; emissions along the Delaware Valley were found to affect the deposition of nitrate and sulfate on the urban mesoscale. The Washington studies were designed to complement and enhance the earlier study with an expanded sampling domain, sequential precipitation sampling and airborne measurements. Four storms were sampled successfully between October 1986 and April 1987. Results appear to confirm the conclusions of the Philadelphia study, although the upwind-downwind contrast in nitrate and sulfate deposition is not as pronounced. This difference is attributed to the area's widely distributed emission patterns and to the prevailing theories regarding the production of nitric acid and sulfuric acid on the relevant time and space scales. The importance of mesoscal...
Raman spectroscopy of a coal liquid shows that fluorescence interference is minimized with ultraviolet excitation

The first ultraviolet resonance Raman measurements of a coal liquid are reported. The spectra detail the presence of numerous polycyclic aromatic hydrocarbons with ring systems similar to those of naphthalene, fluorene, phenanthrene, pyrene, and triphenylene . The ultraviolet resonance Raman measurements of this highly complex sample show no significant interference from fluorescence. The lack of fluorescence interference and the high selectivity indicate that ultraviolet resonance Raman spectroscopy is a powerful new technique for characterizing highly complex samples and mixtures.
Indian lands, “Squatterism,” and slavery: Economic interests and the passage of the indian removal act of 1830

Abstract In May 1830, the U.S. House of Representatives narrowly passed the Indian Removal Act that authorized the president of the United States to exchange land west of the Mississippi River for Indian land in the east and appropriated $500,000 to assist tribes in the move west. Three days later the House also passed the Preemption Act of 1830, giving squatters a right of first refusal to purchase land they had occupied prior to its being opened for sale. In a recent paper, Kanazawa (1996) finds that the willingness of squatters to illegally occupy federal lands greatly raised the cost of enforcing property rights and this was a significant factor behind the passage of the first general Preemption Act in 1830. We build on his work to test the hypothesis that Congressmen who favored squatters’ rights would also favor moving Indian tribes out of the old southwest. A logit analysis of the vote on the Removal Act of 1830 shows three statistically significant variables. Democrats, representatives from slaveholding districts, and those who voted for preemption were more likely to vote for removal. Congressmen from slave states were very likely to favor both Acts, which stands in contrast to southern opposition to a homestead act in the late 1850s.
Software‐Realized Scaffolding to Facilitate Programming for Science Learning

Abstract Programming is an activity through which students can learn about other domains, but the difficulty of programming diminishes its usefulness as a learning activity. One approach to facilitate the use of programming for learning is to view programming as a skill like those taught through apprenticeships, and to use the apprenticeship concept of scaffolding to facilitate doing and learning through programming. Scaffolding means providing modifiable support (through fading) that communicates process, coaches, and elicits articulation. Software‐realized scaffolding embeds scaffolding in a computer‐based environment. Emile implements software‐realized scaffolding to facilitate student learning of physics by facilitating students building computer‐based models and simulations. In this article, I present Emile's features as examples of software‐realized scaffolding, and I present the results of an evaluation of Emile's effectiveness. Students were able to use Emile to create fairly sophisticated program...
Penetration and Permanence of Permethrin in Four Softwoods

We evaluated the 24-h penetration and 6-mo permanence of a 0.5% (AI) dilution of permethrin into southern yellow pine (SYP) ( Pinus spp.), northern hard pine ( Pinus spp.), spruce ( Picea abies ), and fir ( Abies spp.) after surface application. Three- to 12-mo permanence was evaluated only with SYP. Penetration with xylene and nonxylene solvents was evaluated at 24 h. Insecticide (220 μl) was applied to the surface of wood blocks (4 by 5 by 1 cm). After 24 h in the laboratory, or 3 or 6 mo in an attic or crawl space, the center cubic centimeter was removed and sectioned (50 μm per slice) from the treated surface to a depth of 2 mm. Permethrin concentration in each slice was measured by gas chromatography. Penetration of permethrin to 950 μm was not significantly different in SYP than in the other softwoods. At 1600 μm, penetration was not significantly different in SYP, northern hard pine, and fir, but was significantly less in spruce. At depths in wood below 1,200 μm, only the cis isomer of permethrin was detected. At 1,200-, 1,600-, and 2,000-μm depths, more permethrin was present in SYP blocks stored in the attic than in blocks stored in the crawl space. The amount of permethrin at the surface in SYP decreased after 3 mo, but no further decrease after 6 mo in the attic and crawl space was apparent. After 12 mo, a significant decrease in the amount of permethrin at the surface of SYP occurred. Penetration of permethrin in SYP did not differ among solvents; at 950 μm, a significant difference between one nonxylene and a xylene formulation was observed.
In situ ultrasonic measurement of crack closure

This paper describes a surface acoustic wave method for the measurement of crack closure/opening stress during fatigue testing. The dependence of surface wave signature on fatigue load reveals the crack opening/closure characteristics displayed during the fatigue cycle, from which the crack-mouth-opening and fully-crack-opening stresses are determined as functions of the number of cycles. The change of crack closure loads during fatigue life is interpreted by a simple model describing crack growth inside the pit-induced plastic yield zone. The loading-unloading hysteresis is observed and related to the movement of the crack opening/closure front across the boundary of the plastic yield zone during the crack opening-closing process. Examples are given for fatigue tests on Al 2024-T3 and Inconel 718 samples in which the surface fatigue crack initiated from a surface pit.
Acculturation and Health Status Among Hispanic American Elders

Purpose:Hispanic Americans are at risk for health-related problems. Disparities in diseases such as diabetes and obesity, poor access to health services, and lack of health insurance have placed Hispanic Americans at a disadvantage. Sociocultural factors such as acculturation and its relationship to health require further investigation. The primary purpose of this study was to identify the relationship between acculturation and health in Hispanic American elders and examine the interrelationships of acculturation, health status, age, gender, education, years in the United States, and income.Design:This descriptive correlational study was a secondary analysis of data from a large study titled Culture Bias in Testing Expressive Ability in Dementia.Methods:A total sample of 132 community-dwelling Hispanic American elders was used. The Cross Cultural Measure of Acculturation was used to measure acculturation, and health status was measured using the SF-8® Health Survey. Correlation and multiple linear regress...
Kinetics of the Enzymatic Development of Pyruvic Acid and Odor in Frozen Onions Treated with Cysteine C-S Lyase

SUMMARY— Extracts of commercially frozen onion, although possessing considerable peroxidase and catalase activity, were devoid of strong flavor and of L-cysteine sulfoxide lyase activity, the enzyme considered to be responsible for the development of onion flavor. These extracts, having been shown to retain the precursor(s) to such flavor, were selected as model in situ substrates for a study of the kinetics of odor production catalyzed by the L-cysteine C-S lyase of Albizzia lophanta seed endosperm. The results suggest that both odor and pyruvic acid may be produced via the same enzyme but that the odor is formed after the formation of pyruvic acid. From the data it has been calculated that the odor threshold value of some of the enzymatically produced odor-bearing constituents in onions may be less than one part per billion.
General reconstruction characteristics of probabilistic and possibilistic systems

Abstract The subject of this paper is a general empirical study of the reconstruction problem—one of two complementary problems of reconstructability analysis. After a brief overview of relevant concepts, the paper contains a description of the computer experiments performed and the experimental results obtained. These experiments were performed for systems conceptualized in terms of either probability theory or possibility theory. Contrary to all previous experiments in the area of reconstructability analysis, which were based on systems perfectly reconstructable from some subsystems, experiments described here are not idealized in this sense. The significance of the reconstruction principle of inductive reasoning, whose validity is confirmed by the experimental results obtained, is also discussed.
Effects of stress and sulfur dioxide on Spectra

Abstract Polymers are often subjected to aggressive environments where mechanical and chemical mechanisms may act synergistically to degrade the polymers. This research focused on the effects of stress and sulfur dioxide (SO2) environments on ultrahigh molecular weight polyethylene (UHMWPE) fibers (Spectra®). Spectra® yarn specimens were exposed to stress, SO2, and/or near ultraviolet (UV) light environments. Degradation, a decrease in tensile properties, was measured by tensile testing specimens immediately after exposure to the stress/environment conditions. Creep lifetime degradation of Spectra® single fiber specimens was also measured in SO2 and/or near UV light environments. The Spectra® fibers were found to degrade due to the applied stress. This was evidenced by a decrease in the ultimate strength subsequent to an applied creep load and the short creep lifetimes. No chemical degradation was observed, nor were any mechanical–chemical synergisms observed due to the SO2 and/or near UV light environments. The creep lifetimes of the Spectra® fibers, however, increased slightly in environments of SO2 and/or near UV light. The degradation of the Spectra® fibers is consistent with their fibrillar morphology and was attributed to chain scission of the interfibrillar tie chains due to the applied creep load. Since no degradation of the Spectra® was observed in the SO2 and/or near UV light environments, it was concluded that it is relatively insensitive to environmental attack from SO2 and/or near UV light. The increase in the creep lifetimes of the Spectra® fibers suggests that the SO2 and/or near UV light does affect the Spectra® fibers. Based on this and the work of other researchers, it is hypothesized that the SO2 and/or near UV light are, to a limited extent, capable of crosslinking or branching linear polyethylene molecules. Such crosslinking or branching appears to be minimal, altering only the creep lifetimes and leaving the other tensile properties largely unaffected.
Mentoring for Educational Success: Advancing Foster Care Youth Incorporating the Core Competencies

A collaborative relationship among three organizations developed a mentoring project using social work students (mentors) and independent living program (ILP) foster youths (mentees). The goal was to increase the mentees' awareness of educational possibilities beyond high school graduation while analyzing the mentors' learning as defined by the Council on Social Work Education core competencies. This pilot project paired mentors with ILP youths in this experiential opportunity conducted on a university campus. The students, acting as positive role models applying social work skills, engaged in an effort to improve the mentees' educational outcome, which would ultimately lead to self-sufficiency.
La and Zn promotion of Ru Fischer-Tropsch catalysts

An investigation of the use of La- and Zn-promoters for Ru/SiO2 F-T catalysts has been carried out. It was found that, while the use of a La-promoter did not result in any improvement over the use of a K one, Zn-promotion resulted in much higher yields of olefins. The CH4 and olefin selectivities of the Zn-promoted Ru/SiO2 were essentially insensitive to temperature over the range 250–320 °C. The Zn-promoted catalyst was found to have many of the same catalytic properties previously found for Ru/ZnO, but was much more active. Thus, it is possible to achieve certain interesting catalytic properties for Ru by the use of Zn-promotion without having to make use of the low surface area support ZnO.
Structural Design Analysis Applied to Flexible Circuits

A significant consideration to be made with respect to the application of a flexible circuit is the degree to which it can be bent when incorporated into the next level of assembly. The application of stress analysis techniques to arrive at a flexible circuit design that will be structurally sound for a given set of parameters and materials relative to the required application is discussed.
The Pathophysiology and Treatment of Drowning

SUMMARY The pathophysiological changes which occur in both animals and man during drowning and near-drowning with aspiration have been reviewed. Although the fluid and electrolyte changes will differ in patients, depending primarily on the quantity and nature of the fluid that was aspirated, the primary disturbance requiring emergency therapy is acute asphyxia with persistent arterial hypoxemia and acidosis. Initially, the hypoxia is due to perfusion of non-ventilated alveoli. Arterial hypoxemia persists, however, even after a significant intra-pulmonary shunt can no longer be demonstrated. All efforts should be directed to correct this situation with whatever equipment is most readily available. While the patient is being so treated, his fluid and electrolyte status should be evaluated and cor-rected accordingly. Other drug therapy should be supplied as indicated. With this physiological approach to therapy the success rate in resuscitating drowning and near-drowning victims will continue to improve.
Testing and Initial Operating Experience of the MS9001E Gas Turbine

This paper outlines the initial results and experience gained on a newly designed gas turbine with a single shaft and some 100MW output (GE MS9001E). Such turbines may be used either as a simple cycle plant or in the heat recovery mode. A comparison to other units in this class is made. The methods and instruments applied in the test program are described with more details. 4 refs.
Determinants of mTOR inhibitor therapy in AIDS-associated malignancies

Rapamycin/Sirolimus™ leads to the regression of transplant-associated Kaposi sarcoma (KS). It also leads to disease stabilization in HIV-associated KS. Case reports and a wealth of preclinical studies support rapamycin’s efficacy also in AIDS associated lymphoma, such as primary effusion lymphoma (PEL). Rapamycin inhibits the mammalian target of rapamycin (mTOR) and papamycin derivatives are approved for the treatment of mantle cell lymphoma and other cancers. It is not universally effective against all solid tumors. Even within this group of clinically responsive cancers, there are exceptions of cases or cell models in which this drug or its derivatives (rapalogs) fail. We hypothesized that genetic alterations of the tumor will determine the response to rapalogs. We used a novel KS TMA (from the AIDS cancer specimen resource (ACSR) to evaluate the PI3K/Akt/mTOR pathway in KS and identified a unique pattern of protein activation that is associated with sustained expression and phosphorylation of the PTEN tumor suppressor protein. We used Affymetrix array-based comparative genome hybridization (CGH) and targeted sequencing to query genomic loci of members of the mTOR pathway, which confirmed the absence of genetic alterations, which in other cancers have been associated with mTOR pathway activation. We conclude that in KS, PEL and perhaps other virus-associated cancer the mTOR pathway is activated post-translationally, which is not as permanent and does not have the same impact as for instance a deletion in PTEN. This may explain the unique sensitivity of these tumor types to rapalogs. We established a novel animal model of KS (L1T2 cells), which develops tumors with short latency and in which the KS associated herpesvirus (KSHV) is maintained in each tumor cell. We evaluated multiple rapalogs (Sirolimus™, Temsirolimus™, Everolimus™), Tacrolimus/FK506 and Doxil™ in this model. We found sustained, but reversible tumor suppression by the rapalogs, which was associated (a) with inhibition of mTOR activity and (b) with reduced neo-angiogensis. In this model rapalogs outperformed Doxil™, presumably because of a combined effect on endothelial lineage KS tumor cells and endothelia lineage tumor vasculature. This represents the first animal test of rapalogs in a human KS tumor model, it validates novel biomarkers and provides a strong rational for further clinical development and testing of rapalogs in AIDS-associated Kaposi sarcoma. As rapamycin has recently become affordable and is available in developing countries, where the majority of KS-associated mortality occurs, it is one of the few new anti-cancer drugs with a cost/benefit profile that is affordable for global cancer treatment.
Re-examining the BMI Threshold for Bariatric Surgery in the USA

The optimal BMI threshold above which gastric bypass surgery should be offered to obese patients is controversial. The objective of this study was to compare the impact of Roux-en-Y gastric bypass (RYGB) vs. diet and exercise (D&E) on life expectancy to find the BMI at which patients experience an improvement in their life expectancy by undergoing surgery. A Markov state transition model was designed to implement a decision tree that simulated the lives of obese patients. Life expectancies following RYGB and 2 years of D&E were estimated and compared. Ten thousand patients’ lives were simulated in each weight-loss intervention group in the model. In addition to base case analysis (45 kg/m2 BMI pre-intervention), sensitivity analysis of initial BMI at the start of the study was completed. Markov model parameters were extracted from the literature. The impact of RYGB on survival relative to D&E depended on the patient’s initial BMI. Compared to patients who underwent 2 years of “optimal” diet and exercise (7 % total body weight loss/year), RYGB improved long-term survival for patients above a BMI of 31.3 kg/m2. Roux-en-Y gastric bypass can improve long-term survival for patients with class I obesity. This study suggests that RYGB should not be reserved solely for patients with class II or III obesity.
Semiconducting YBCO bolometers for uncooled IR detection

Amorphous semiconducting Y-Ba-Cu-O is attractive as the temperature sensitive element for uncooled IR bolometers and pyroelectric detectors. Thin films can be easily fabricated by RF magnetron sputtering at room temperature from a composite target. It is compatible with micromachining techniques for the fabrication of thermally isolated structures. As a bolometer, Y-Ba-Cu-O possesses a relatively high temperature coefficient of resistance of 3.5% K-1 near room temperature. This paper will present the IR characteristics of 40-micrometer X 40-micrometer microbolometer arrays fabricated in thermal isolation structures. These detectors are aimed at thermal imaging at 10-micrometer wavelength. Recently, self-supporting YBaCuO pixels have been developed. In this case, the Y-Ba-Cu-O thin film pixel requires no underlying bridge material to provide structural support. The Y-Ba-Cu-O thin film is supported solely by the electrode arms. Responsivity and detectivity greater than 4 X 103 V/W and 108 cmHz1/2/W respectively have been measured in these detectors. The development of large area 1.5-mm and 0.4- mm square YBaCuO bolometers for NASA's global warming studies in low-orbiting satellites will also be presented. These large area detectors require large optical bandwidths covering the 0.3-micrometer to 100-micrometer wavelength band.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Medical management of thoracic aortic aneurysm disease

The patient with thoracic aortic aneurysm disease requires careful evaluation and management over his or her lifetime. This includes assessment for the presence of an underlying genetic disorder, such as Marfan syndrome, bicuspid aortic valve disease, or a familial aortic aneurysm syndrome. Screening family members is necessary, inasmuch as up to 20% of first-degree relatives of the patient with a thoracic aortic aneurysm will also have aneurysm disease. Medical therapy is often prescribed, and beta-blocker therapy to reduce the stress on the aortic wall is usually recommended. However, very few clinical trials of pharmacologic therapy in humans with thoracic aortic aneurysm disease have been conducted. Mouse models have led to important discoveries and insight into the pathogenesis of aneurysm syndromes, and there is hope these may lead to effective therapy in people. Several studies are ongoing that examine the role of angiotensin receptor blockers in Marfan syndrome. Lifestyle modification is also important for patients with thoracic aortic aneurysm, including restrictions on physical activity, weight lifting, and recommendations about the management of pregnancy. Long-term surveillance of the aorta, even after successful surgery, is necessary for timing of prophylactic surgery and to evaluate for late complications.
Light-Induced Reactions of Porous and Single-Crystal Si Surfaces with Carboxylic Acids

Light-induced reactions of Si surfaces with carboxylic acids to generate Si ester-modified surfaces are studied. The reaction proceeds by photoelectrochemical oxidation of porous or (100)-oriented single-crystal n-type Si in formic, acetic, or trifluoroacetic acid electrolyte solutions. The reaction products at the porous Si surface are identified by Fourier-transform infrared (FTIR) spectroscopy. Derivatization with esters reduces the photoluminescence intensity of porous Si. X-ray photoelectron spectroscopy (XPS) of derivatized single-crystal Si is used to confirm the compositional and bonding information and to demonstrate that the same chemistry occurs at a single-crystal Si surface. A mechanism is proposed in which illumination of reverse-biased Si removes electron density from the Si surface, rendering Si−Si bonds susceptible to nucleophilic attack by carboxylic acid. The reaction has a marked dependence on light intensity and the Si surface can be photopatterned by illumination through a mask durin...
A Minimally Invasive Approach to an Iatrogenic Pelvic Mass

A case report describing an unusual complication following a 17-week elective termination of pregnancy in a pediatric patient that was managed laparoscopically.
Improved Monte Carlo methods for fermions

Abstract We describe an improved version of the Kuti-Von Neumann-Ulam algorithm useful for fermion contributions in lattice field theories. This is done by sampling the Neumann series for the propagator, which may be thought of as a sum over a set of weighted paths between two points on the lattice. Rather than selecting paths by a locally determined random walk, we average over sets of paths globally preselected for their importance in evaluating the few needed elements of the inverse. We also describe a method for the calculation of ratios of fermion determinants which is considerably less time consuming than the conventional one.
The ion‐exchange chromatographic determination of antihistamines

Abstract The number of methods for the quantitative determination of antihistamines is almost as numerous as the substances themselves. Colorimetric, gravimetric, Polarographie, volumetric, and spectrophotometric procedures have Been applied to determine quantitatively antihistaminic compounds. However, no general method exists. The primary purpose of this study was to develop a new method, using ion exchange techniques, for the analysis of antihistamines. The method developed was applied to antihistamines in the three major groups, i. e., basic ethers, derivatives of ethylenediamine, and monoamines. Tablets, elixirs, and ointments were assayed using ion exchange techniques. The results of the study clearly indicate the usefulness and practicality of the ion exchange procedure in the pharmaceutical analysis of antihistamine salts.
Potential defense-related prenylated isoflavones in lactofen-induced soybean.

Abstract An integrated LC-MS and NMR metabolomic study was conducted to investigate metabolites whose formation was induced by lactofen ( 1 ), a soybean ( Glycine max L.) disease resistance-inducing herbicide. First, LC-MS analyses of control and lactofen ( 1 )-induced soybean extracts were performed. The LC-MS raw data were then processed by a custom designed bioinformatics program to detect the induced metabolites so formed. Finally, structures of unknown induced metabolites were determined on the basis of their 1D and 2D NMR spectroscopic data. Structure of two previously unreported compounds, 7,8-dihydroxy-4′-methoxy-3′-prenylisoflavone ( 2 ) and 7-hydroxy-4′,8-dimethoxy-3′-prenylisoflavone ( 3 ) were elucidated together with four known prenylated compounds, 3′-prenyldaidzein ( 4 ), 8-prenyldaidzein ( 5 ), 3′-prenylgenistein ( 6 ), and 4-prenylcoumestrol ( 7 ). Compounds ( 2 – 6 ) are reported for the first time in soybean, as are the 13 C chemical shift assignments for compound ( 7 ). Formation of these six prenylated compounds was also induced by the primary defense glucan elicitor from the cell wall of the pathogen Phytophthora sojae (Kauf. and Gerde.), further suggesting a potential role in soybean defense. These results highlight the metabolic flexibility within soybean secondary product pathways and suggest that prenylation may be associated with defense responses. Moreover, this study demonstrates a promising future approach using metabolomics on elicitor-induced plants for discovery of unknown compounds even in relatively well studied plants.
Modulation of the membrane type 1 matrix metalloproteinase cytoplasmic tail enhances tumor cell invasion and proliferation in three-dimensional collagen matrices

Increasing evidence suggests that the cytoplasmic tail of membrane type 1 matrix metalloproteinase (MT1-MMP) is subject to phos pho ryl a tion and that this modification may influence its enzymatic activity at the cell surface. In this study, phos pho ryl a ted MT1-MMP is detected using a phospho-specific antibody recognizing a protein kinase C consensus sequence (phospho-TXR), and a MT1-MMP tail peptide is phos pho ryl a ted by exogenous protein kinase C. To characterize the potential role of cytoplasmic residue Thr567 in these processes, mutants that mimic a state of either constitutive (T567E) or defective phos pho ryl a tion (T567A) were expressed and analyzed for their functional effects on MT1-MMP activity and cellular behavior. Phospho-mimetic mutants of Thr567 exhibit enhanced matrix invasion as well as more extensive growth within a three-dimensional type I collagen matrix. Together, these findings suggest that MT1-MMP surface action is regulated by phos pho ryl a tion at cytoplasmic tail residue Thr567 and that this modification plays a critical role in processes that are linked to tumor progression.
Biphasic Defibrillation Waveforms Reduce Shock-Induced Response Duration Dispersion Between Low and High Shock Intensities

Abstract Mechanisms underlying defibrillation threshold reduction with biphasic waveforms remain unclear. The interaction of local shock-induced voltage gradients, which change with distance from the shocking electrode, and the state of membrane repolarization results in different cellular responses that may influence the success of defibrillation. We used intracellular microelectrodes and S1S2 pacing protocols in myocardial cell aggregates to determine the effects of shock intensity and waveform on refractory period responses during simulated fibrillation (3 s of S1 pacing at 180-ms cycle length). We simulated defibrillation by electric field stimulation S2 using 8-ms monophasic (MS2) and 4/4 biphasic (BS2) waveforms (65% total tilt) delivered at intensities of 1.5, 3, and 5 times S1 diastolic threshold, or ≈2 to 7 V/cm. Responses following MS2 varied with S2 intensity and coupling interval ( P <.001). When averaged over the last 10 ms of the refractory period, MS2 produced a negligible response (8.8±1.4 ms) at 1.5 times diastolic threshold and a prolonged response (53.0±3.1 ms) at 5 times diastolic threshold ( P <.01). In contrast, BS2 response duration did not change significantly ( P =NS) between 1.5 times diastolic threshold (35.1±12.6 ms) and 5 times diastolic threshold (46.2±2.7 ms). Our results suggest that biphasic waveforms not only prolong response duration at low shock intensity but reduce dispersion of refractoriness produced by differing local potential gradients generated by defibrillation shocks compared with monophasic waveforms. Preventing dispersion of refractoriness and prolonging shock-induced responses may improve biphasic waveform efficacy at low shock intensity.
Cl2 molecular elimination reaction from 1,2-dichloroethane

Abstract The transition state energy for Cl2 molecular elimination from 1,2-dichloroethane is computed at compostite CBS-Q (based on B3LYP/6-31++G(d) optimized structure) and G3MP2 (based on MP2/6-31++G(d) optimized structure) levels of theory. Forward rate constants are calculated as 4.25 E11 T 0.826 · exp (−93.4 kcal mol −1 / RT ) and 7.62 E10 T 0.892 · exp (−98.5 kcal mol −1 / RT ) s −1 , respectively for these two methods. Intrinsic reaction coordinate (IRC) analysis is performed to verify the transition state structures. While the overall, elimination of Cl2 plus olefin formation has a relative low ΔHrxn; the reaction with these barriers is evaluated to be not important in thermal reactions of chlorocarbons.
Interactive display of molecular models using a microcomputer system

A simple, microcomputer-based, interactive graphics display system has been developed for the presentation of perspective views of wire frame molecular models. The display system is based on a TERAK 8510a graphics computer system with a display unit consisting of microprocessor, television display and keyboard subsystems. The operating system includes a screen editor, file manager, PASCAL and BASIC compilers and command options for linking and executing programs. The graphics program, written in USCD PASCAL, involves the centering of the coordinate system, the transformation of centered model coordinates into homogeneous coordinates, the construction of a viewing transformation matrix to operate on the coordinates, clipping invisible points, perspective transformation and scaling to screen coordinates; commands available include ZOOM, ROTATE, RESET, and CHANGEVIEW. Data file structure was chosen to minimize the amount of disk storage space. Despite the inherent slowness of the system, its low cost and flexibility suggests general applicability.
Recombination versus Disproportionation Reactions of Hydrogen Atoms with ClCF2CHF, ClC2F4, BrC2H4, BrC2F4, and BrCF2CFBr Radicals and Unimolecular Reactions of the Haloethane Molecules from Recombination

The reactions of hydrogen atoms with the ClCF2CHF, ClC2F4, BrC2H4, BrC2F4, and BrCF2CFBr radicals have been studied at room temperature and 1 Torr pressure of Ar by an infrared chemiluminescence technique in a flow reactor. The H + CF3CH2 recombination reaction was also examined to provide a reference point to earlier experiments from this laboratory. The recombination step generates vibrationally excited molecules that undergo HX(X = Br, Cl, F) elimination at 1 Torr of pressure. The characteristic low vibrational excitation, 〈fV(HX)〉 ≈ 0.15, with a monotonically declining distribution from unimolecular 1,2-HX elimination reactions versus 〈fV(HX)〉 ≈ 0.35 with an inverted distribution from disproportionation, or direct halogen atom abstraction, reactions is used as a diagnostic test for recombination versus disproportionation mechanisms. Upon the basis of the observed HBr vibrational distributions, the H + BrC2F4 reaction has a small Br atom abstraction component that is superimposed upon the HBr vibration...
Return to obscurity

Boninites and Related Rocks. By A. J. Crawford Unwin Hyman: 1989. Pp.465. £60, $90. Carbonatites; Genesis and Evolution. By Keith Bell. Unwin Hyman: 1989. Pp.618. £85, $125.
A link between terrestrial gamma‐ray flashes and intracloud lightning discharges

[1] Atmospheric electric field change (sferic) waveforms were detected at Los Alamos Sferic Array stations in association with terrestrial gamma-ray flashes (TGFs). Five TGF sferic waveforms detected at sufficiently close range were all found to be consistent with a positive-polarity intracloud (+IC) discharge process which transported electrons upward. The amplitudes of the events were among the top 5% of IC discharge flashes. Altitudes obtained from ionosphere reflections for two of the closer events were found to be 13.6 km and 11.5 km. These altitudes are lower than expected if one assumes that the sferic was near the source of the gamma-rays. One of the sferics was an energetic narrow bipolar event which occurred near the inferred onset of a flash, suggesting that the preceding TGF may correspond to the actual onset.
Pain thresholds in alcohol preferring and non-preferring rats: diurnal and repeated trial line differences.

Background: Studies in humans and animals suggest that those with a genetic predisposition toward high levels of alcohol consumption have decreased pain thresholds. The present study explores this association in rat lines selectively bred for alcohol preference or nonpreference. Methods: 13 HAD1, 11 LAD1, 16 iP5C, and 16 iNP1 rats were tested in the Ugo Basile Plantar Analgesiometer and the IITC Tail Flick device. Five trials were conducted in each test session with one session per device conducted in the light and one in the dark. Trial one latency represents baseline latency. Decline in Latency over Repeated Trials (DLRT) was analyzed using linear regression. Results: Testing in the Plantar Analgesiometer revealed no significant line differences in baseline latency (iP5C versus iNP1; HAD1 vs. LAD1). The alcohol preferring lines (iP5C and HAD1), however, both demonstrated an increase in baseline latency in the dark phase compared to the light phase (p < 0.05). The iNP1 line demonstrated highly significant DLRT in both the light phase (p < 0.001) and dark phase (p < 0.01) while the iP5C line demonstrated a significant DLRT only at night (p < 0.01). In the tail flick apparatus, the HAD1 line demonstrated a significantly increased baseline latency compared to the LAD1 line in both the light (p < 0.05) and dark (p < 0.01) phases. The HAD1 line also demonstrated a significant increase in baseline latency in the dark compared to the light phase (p < 0.05) and a significant DLRT in the light (p < 0.01) and the dark phase (p < 0.001). Conclusions: The alcohol preferring HAD1 line demonstrates a significantly increased baseline tail latency compared to the nonpreferring LAD1 line in both light and dark phases. There is a significant diurnal rhythm of paw and tail latency in both of the alcohol preferring lines (iP5C and HAD1) but not in the nonpreferring lines (iNP1 and LAD1). A novel finding of Decline in Latency with Repeated Trials (DLRT) was found in both alcohol preferring and nonpreferring lines; degree of DLRT differed as a function of line and circadian period.
Detection and Treatment of Hypertension at the Work Site

Abstract A program linking detection to treatment was designed to improve blood-pressure control among adults with asymptomatic, uncomplicated hypertension. Key elements of this program were provision of all diagnostic and therapeutic services at work site, integration of delivery system with the administration of a labor union, adherence to a rigid protocol, and continuous patient surveillance by nurses and paraprofessionals. At the first program site, Gimbels's principal New York City department store, 84 per cent of 1850 employees were screened, and 65 per cent of 186 with confirmed hypertension elected the treatment program. Of the 94 patients followed for one year, 97 per cent remained under therapy, with no untoward effect, and 81 per cent of patients had satisfactory blood-pressure reduction. This approach appears to be a safe, effective, and acceptable method for hypertension control in large numbers of patients. (N Engl J Med 293:65–68, 1975)
Electrochemical investigations of polypyrrole aluminum flake coupling

Abstract Polypyrrole (PPy) Al flake composite (PAFC) was synthesized by chemical oxidation of pyrrole in the presence of Al flake and was used to formulate a corrosion inhibiting primer. The anticorrosion performance of the PAFC coating for AA 2024-T3 was evaluated by accelerated salt spray, scanning vibrating electrode technique (SVET), galvanic coupling measurement and electrochemical impedance spectroscopy (EIS). The PAFC primer showed an enhanced anticorrosion ability for AA 2024-T3 compared to the Al flake primer and provided cathodic protection for AA 2024-T3 as evidenced by galvanic coupling measurement. A possible corrosion protection mechanism provided by the PAFC and the role of PPy in the formulation were discussed.
Planar aqueous electrode technique for polymer impedance spectroscopy

In this article, we develop an aqueous electrode technique that can adapt to complex sample geometries while maintaining perfect contact between the electrodes and the measured sample. In contrast to surface deposited electrodes, the aqueous electrode technique measures the ionic conduction of the polymer sample instead of the inherent dielectric properties of the polymer. Polymer ionic conduction is often related to the polymer thermodynamic state, which itself is closely linked to many other polymer properties. As such, the aqueous electrode method provides an approach to conduct in situ monitoring of polymer samples subjected to degradation; changes in the impedance provide an indication of polymer sample degradation. This article presents the aqueous electrode setup and discusses experimental results obtained using it. Changes in the impedance response of PVC and polyimide films due to moisture absorption, ionic conduction, pinholes, chemical degradation, and temperature are presented. POLYM. ENG. SCI., 2009. © 2008 Society of Plastics Engineers
The archaic prehistory of the North American Southwest

Evidence today suggests that by at least 8000 to 8500 B.P., Archaic hunter-gatherer economies were established throughout the North American Southwest. The Early Archaic seems to be a period of considerable variability across the subregions; this may be a product of currently slim knowledge of the period, or it may indicate that the region witnessed considerable flux. With the Middle Archaic period from 5500 to 3500 B.P. there seems to be greater similarity in material culture across the region and a definite increase in the number of known sites. Finally, the Late Archaic/Early Agricultural period from 3500 to 2000 or 1500 B.P. sees the establishment of a mixed farming-foraging economy in much of the Southwest with apparently major changes in subsistence-settlement systems. Preagricultural Archaic land use patterns are known in broad outline but not in detail; high mobility by small social groups in an annual round would have permitted exploitation of diverse biotic communities. In most parts of the region, significant socioeconomic change accompanies the incorporation of agriculture into the late preceramic period, as witnessed by the appearance of longer-term residential sites with pitstructures and storage features.
Experimental evidence for the metastability of neon hydride

Abstract The neutralization-reionization mass spectrum of NeD+ has been obtained using K as a neutralization target and NO2 as a collisional reionization target. The appearance of the parent NeD+ peak in the mass spectrum unambiguously indicates that the neutral radical survived the transit time (≈ 0.5 μs) from the point of neutralization to that of reionization. Arguments, based on energetic considerations, are presented that the observed metastability arises from the existence of a shallow well and dissociation barrier in the ground state of the radical analogous to those which have previously been determined for the ground states of the isoelectronic NH4, H3O, and H2F radicals.
Influence of urine pH on accurate urinary protein determination in Sprague-Dawley rats

BACKGROUND Rat urinary protein concentration is commonly measured during safety assessment studies to evaluate potential drug-induced nephrotoxicity. It has been reported that impregnated reagent test strips (dipsticks) can yield false-positive urinary protein results for alkaline urine samples. OBJECTIVE The objective of this study was to determine if urinary dipsticks accurately assess protein concentrations, especially in alkaline rat urine. METHODS Ten male Sprague-Dawley rats were treated with 2% sodium bicarbonate and 2% ammonium chloride to alkalinize and acidify the urine, respectively. Urine pH was measured in treated and control rats using a pH meter and urinary dipsticks with the Clinitek 500. Quantitative urinary protein results were compared to urinary dipstick protein evaluations obtained with the Clinitek 500 and sulfosalicylic acid precipitation test methods. RESULTS The urinary dipstick pH measurement had a very high correlation (r = .98) with the pH meter technique. Samples with alkaline pH (>or=7.5) analyzed for protein by dipstick analysis were in complete agreement 34.7% of the time with the quantitative technique, which was very similar to the 39.3% agreement for samples with neutral and acidic pH (<or=7.0). Samples with alkaline pH analyzed by the sulfosalicylic acid method were in agreement 0% of the time with the quantitative technique, compared to 7.1% of the time with samples with neutral or acidic pH. CONCLUSION The urine dipstick method does not lead to gross overestimation of urinary protein concentration in alkaline urine and provides a rapid and reasonably accurate way of determining the presence or absence of urinary protein in rats.
Diversity of cutinases from plant pathogenic fungi: differential and sequential expression of cutinolytic esterases by Alternaria brassicicola

Plant cuticles provide a protective layer that has to be penetrated by fungal pathogens. Evidence is provided for a differential and sequential induction of two classes of cutinolytic esterases by Alternaria brassicicola. Serine esterases with cutinolytic activities were expressed by conidia germinating on host surfaces. The enzymes were not induced by surface wax or cutin monomers. They were only expressed during initial (24 h) contact of conidia with cutin on host surfaces freed from wax, and with cutin in aqueous suspensions. In contrast, contact with cutin had no immediate effect on the expression of CUTAB1, a gene encoding two cutinase isozymes with crucial functions in the saprophytic utilization of cutin. Presence of a cutin monomer or prolonged exposure to cutin was required for the induction of CUTAB1 expression. The differential induction of cutinolytic esterases indicates a sequential recognition of cutin as a barrier to be penetrated and to be utilized as a carbon source in saprophytic stages.
823 RADIOLOGIC AND VIROLOGIC FEATURES OF RESPIRATORY SYNCYTIAL VIRUS (RSV) PNFUMONIA: IMPLICATIONS FOR DIAGNOSIS AND THERAPY

823 RADIOLOGIC AND VIROLOGIC FEATURES OF RESPIRATORY SYNCYTIAL VIRUS (RSV) PNFUMONIA: IMPLICATIONS FOR DIAGNOSIS AND THERAPY
Contestation and Mutual Adjustment: The Process of Controlling Land in Yajouz/ Jordan

For the past two decades, land in Yajouz has been the locus of fierce contestation between the government of Jordan, the Bani Hasan tribe, and new settlers. Today, Yajouz is a peripheral urban settlement deemed illegal by the government. Three main factors have contributed to the making of Yajouz in its present form: (1) the contested nature of claims to land; (2) the plurality of control mechanisms and ordering of the social and the geographical space, allowing the land market to develop as a semi-autonomous social field; (3) the process of mutual adjustment between state organs and the Yajouz social field, defining the security of tenure among settlers and the social functioning of law. I argue that the Yajouz market does not manifest a traditional phenomenon giving way to modernity; it is rather a modern phenomenon itself shaping and being shaped by the daily functioning of law. In this case, conflicting claims to resources have been catalysts for the development of a semi-autonomous social field, which in turn has engaged state organs in a process of mutual adjustment.
DO INSIDERS PRACTICE WHAT THEY PREACH? INFORMED OPTION EXERCISES AROUND MERGERS AND ACQUISITIONS

We examine executive stock option exercises around a sample of merger and acquisition announcements between 1996 and 2006, focusing on a subset we identify as potentially informed. For stock-financed acquisitions, we find a surge in informed exercises by acquirer insiders in the year leading up to the acquisition announcement, but target insiders display no similar increase. We find the market reaction upon the announcement for acquirers is negatively related to extreme early exercises and find some evidence of long-run underperformance. Overall, our evidence indicates that insiders knowingly bid for firms when they personally believe their own firm is overvalued.
Catalytic conversion of compounds representative of lignin-derived bio-oils: a reaction network for guaiacol, anisole, 4-methylanisole, and cyclohexanone conversion catalysed by Pt/γ-Al2O3

The conversion of compounds representative of lignin and lignin-derived bio-oils (guaiacol, anisole, 4-methylanisole, and cyclohexanone), catalysed by Pt/Al2O3 in the presence of H2 at 573 K is described by a reaction network indicating a high selectivity for platinum-catalysed aromatic carbon–oxygen bond cleavage accompanied by acid-catalysed methyl group transfer reactions.
Direct measurement of young's modulus in the sliding and nonsliding CDW state of TaS3

Abstract Stress δ was applied to TaS3 whiskers at temperatures above and below the charge density wave (CDW) transition. The resulting changes in the strain ϵ and resistance of the sample were measured at each temperature. The δ-ϵ data, yielding a direct measurement of Young's Modulus (Y), implies that Y along the growth direction is 150 GPa at T = 130K. When δ ≥ MPa at 130K (causing ϵ to be ≥ 5 × 10−4), an electric field E three times greater than the threshold field ET was found to change ϵ by less than 1 × 10−6. Thus, at this δ, Y changes less than about 2 parts in 103 (0.2%) when the CDW is depinned, which is much less than changes found from vibrating reed experiments. At δ ≈ 20 MPa, where we have less sensitivity we find no changes in Y to 1 part in 102 (1%). We also performed the experiment using an oscillating δ (f ≤ 6 Hz) which produces an oscillating ϵ whose amplitude is proportional to Y. This method was found to yield no changes in Y to 1 part in 102 at σ ≈ 20 MPa. These results will be compared and contrasted to recent experiments by Xiang and Brill (1) on the frequency den3edence of Y in TaS3 and to the theories on elastic properties of CDW conductors.