cssi/SciSciGPT-SciSciNet huggingface dataset:
An experimental evaluation of simple methods for seeding program errors

This paper describes an experiment in which simple syntactic alterations were introduced into program text in order to evaluate the testing strategy known as error seeding. The experiment's goal was to determine if randomly placed syntactic manipulations can produce failure characteristics similar to those of indigenous errors found within unseeded programs. As a result of a separate experiment, several programs were available, all of which were written to the same specifications and thus were intended to be functionally equivalent. The use of functionally equivalent programs allowed the influence of individual programmer styles to be removed as a variable from the error seeding experiment. Each of six different syntactic manipulations were introduced into each program and the mean times to failure for the seeded errors were observed. The seeded errors were found to have a broad spectrum of mean times to failure independent of the syntactic alteration used. We conclude that it is possible to seed errors using only simple syntactic techniques that are arbitrarily difficulty to locate. In addition, several unexpected results indicate that some issues involved in error seeding have not been addressed previously.
Turning students into science stars (science and engineering education)

To meet the demands for greater numbers of biomedical engineers, it is necessary to expand the biomedical engineering and related educational programs in the United States to provide students with a focused exposure to basic science, engineering, and technology development principles central to advances in this industry. Over the past 30 years, however, the United States has seen a precipitous decline in the number of American students studying science and engineering. It is this downward spiral the Biomimetic Microelectronic Systems Engineering Research Center (BMES ERC) Education Outreach Program seeks to address. This program affects the science literacy of more than 2,000 minority and economically disadvantaged Los Angeles Unified School District students and their teachers each year. In addition, the BMES ERC has augmented the course curricula of undergraduate and graduate students. All facets of the program are facilitated by experience-dependent mentoring throughout the entire curriculum, using BMES ERC testbeds and thrusts research as focal points of learning and motivation. Through its outreach program, BMES ERC scientists and engineers transfer the excitement, knowledge, and skills generated by their research to students from grade school to graduate school.
Notiz zur Synthese von 3-[Alkyl(aryl)thio]isoindolinonen aus 2-Formylbenzoesäure-methylester

Note on the Synthesis of 3-[Alkyl(Aryl)thio]isoindolinones from Methyl 2-Formylbenzoate In a one-pot procedure the isoindolinone derivatives 6 have been obtained from methyl 2-formylbenzoate, primary amines, and thiols via the intermediate imines 1.
MOLECULAR MODELS FOR VERTEBRATE LIMB DEVELOPMENT

We would like to thank J. Fallon, C. Tickle, H.-C. Lu, and G. Eichele for their critical comments on this manuscript.
Role of interleukin-2 in superantigen-induced T-cell anergy.

T-cell anergy is a state of immunological tolerance characterized by unresponsiveness to antigenic stimulation. Previous studies have shown that anergy is induced in T cells following stimulation in the absence of adequate costimulatory signals. These cells fail to respond to stimulation via the T-cell receptor (TCR), and fail to produce normal levels of interleukin-2 (IL-2). We present results here which show that low concentrations of the superantigen staphylococcal enterotoxin A (SEA) in the absence of antigen-presenting cells induced both proliferation and anergy in the A.E7 T-cell clone. Furthermore, under these conditions, the A.E7 clone remained responsive to exogenous IL-2. Fluorescence-activated cellular cytometry analysis revealed unaltered expression of the TCR/CD3 complex in the anergized clone; however, both CD4 and CD25 expression increased after 24 hr of stimulation by SEA under these conditions. Interestingly, a low level of IL-2 production was measured during the induction of anergy. Most strikingly, stimulation of the A.E7 clone by SEA in combination with exogenous IL-2 resulted in a more pronounced state of anergy. These results suggest that the induction of anergy is a process that is essentially independent of the production of IL-2.
BIOSYNTHESIS OF TRANSFERRIN-RECEPTOR IN HUMAN SMALL INTESTINAL CELLS

Biopsies from human small intestine were studied in organ culture by labelling newly synthesised proteins with 35S-methionine for 6 hours continuous pulse or for 10 minutes pulse followed by chase with excess of cold methionine for different time intervals. Biopsies were further processed by immunoprecipitation with monoclonal antibodies (OKT 9) against human transferrin receptor (TR). Electrophoretic analysis of the precipitates by SDS–PAGE in normal mucosa revealed immature TR-precursor with apparent molecular weight of 87 Kd after 50 minutes of chase. At 80 minutes of chase the mature form of TR with an apparent molecular weight of 90 Kd was noted. When iodinated transferrin (125I) was incubated with microvillar membrane fraction and crosslinked with dimethyl-3-3'-dithiodispropriominidate two bands were visible on SDS-PAGE under nonreducing conditions: one representing the transferrin and the second corresponding to the transferrin-TR-complex. The organ culture of totally flat mucosa from a patient with untreated celiac disease for 6 hours continuous pulse demonstrated no TR molecule on SDS-PAGE in contrast to normal mucosa. Conclusion: TR is synthesised in human intestinal mucosa within 50 minutes in organ culture. TR is absent in acute celiac disease suggesting that this defect might play a role in the pathogenesis of iron deficiency in this condition.
The ring of life provides evidence for a genome fusion origin of eukaryotes

Genomes hold within them the record of the evolution of life on Earth. But genome fusions and horizontal gene transfer seem to have obscured sufficiently the gene sequence record such that it is difficult to reconstruct the phylogenetic tree of life. Here we determine the general outline of the tree using complete genome data from representative prokaryotes and eukaryotes and a new genome analysis method that makes it possible to reconstruct ancient genome fusions and phylogenetic trees. Our analyses indicate that the eukaryotic genome resulted from a fusion of two diverse prokaryotic genomes, and therefore at the deepest levels linking prokaryotes and eukaryotes, the tree of life is actually a ring of life. One fusion partner branches from deep within an ancient photosynthetic clade, and the other is related to the archaeal prokaryotes. The eubacterial organism is either a proteobacterium, or a member of a larger photosynthetic clade that includes the Cyanobacteria and the Proteobacteria.
Studies of transformations of inorganic constituents in a Texas lignite during combustion

Abstract The mechanisms of coal ash formation were studied under closely controlled combustion conditions. Monticello lignite, from Titus County, Texas was combusted in a drop-tube furnace at 1500°C and fly ash was collected and aerodynamically size segregated into six stages. Short residence time chars were also produced in the drop-tube furnace. The coal was analyzed to determine both mineralogical and organically bound components using computer controlled scanning electron microscopy (CCSEM) and chemical fractionation techniques, respectively. Scanning electron microscopy/microprobe techniques were used to classify and determine the distribution of various ash particle types in each size fraction. Over 80% of the Monticello mineral content consisted of quartz and clay minerals and relatively large quantities of Ca, Mg, and possibly Fe were organically bound. Extensive reaction between the quartz and clay minerals and organically bound Ca resulted in amorphous and crystalline Ca-silicate and Ca-aluminosilicate phases in the fly ash. Finely subdivided discrete minerals or organically bound cations of Mg and Fe were concentrated in the finer fraction of the fly ash.
The picosecond time-resolved fluorescence spectrum of rhodamine 6G

Abstract We have observed the spontaneous flourescence spectrum of rhodamine 6G in glycerol with picosecond resolution using a mode-locked Nd:glass laser. The position, width and shape of the fluorescence spectrum are a function of the delay time between excitation and observation of the spectrum. Initially, the spectrum is close to a lorentzian with 12 nm halfwidth centered at 559 nm. The spectrum finally evolves to a skewed gaussian lineshape of 37 nm halfwidth centered at 569 nm. These results imply that the fluorescence spectrum is inhomogeneously broadened.
Overview of the University of Pennsylvania CORE system: standard graphics package implementation

The CORE System is a proposed standard for a device-independent graphics system. The concept of a deviceindependent system was first developed in 1977 by the Graphics Standards Planning Committee (GSPC) of ACM Siggraph and later refined in 1979 [1,2]. The CORE System design has received favorable reviews and has been implemented by various vendors at several universities, and other computing facilities (e.g. [3,7]). The main objectives of the CORE System are to provide uniformity, compatibility, and flexibility in graphics software. Three advantages that the CORE system provides over non-standard graphics systems are device independence, program portability, and functional completeness. A large number of different graphics hardware devices currently exist with a wide range of available functions. The CORE System provides device independence by shielding the applications programmer from specific hardware characteristics. The shielding is at the functional level: the device-independent (DI) system uses internal routines to convert the application programmer's functional commands to specific commands for the selected hardware device driver (DD). The progammer describes a graphical world to the CORE System in device-independent normalized device coordinates. The programmer also specifies the viewport on the logical view surface (output device) where a picture segment is to be placed. As the CORE System becomes the accepted standard graphics package, program portability will become more feasible. Program portability means the ability to transport application programs between two sites without requiring structural modifications. The CORE System was designed for functional completeness so that any graphics function a programmer desires is either included within the system or can be easily built on top of CORE System routines. Disciplines Computer Engineering | Computer Sciences Comments University of Pennsylvania Department of Computer and Information Science Technical Report No. MSCIS-82-17. This technical report is available at ScholarlyCommons: http://repository.upenn.edu/cis_reports/1004
Serotonergic dorsal raphe neurons: Subsensitivity to amphetamine with long-term treatment

Abstract Rats were pretreated twice daily for six consecutive days with either saline or 1.0, 5.0, or 10.0 mg/kg (+)-amphetamine. On the following day, single-unit recording techniques were used to identify serotonin-eontaining neurons in the dorsal raphe nucleus (DRN). Pretreatment with amphetamine did not alter the mean spontaneous firing rate of these cells, but in some instances it appeared to produce periods of irregular bursting. Moreover, the response to challenge injections of amphetamine was reduced significantly by pretreatment with the large dose. Thus, whereas an intravenous challenge of approximately 3.0 mg/kg produced a greater than 50% inhibition of activity in the dorsal raphe nucleus in rats pretreated with saline, 1.0 or 5.0 mg/kg (+)-amphetamine, more than twice the challenge dose was required to suppress the activity of serotonergic neurons in rats pretreated with 10.0 mg/kg (+)-amphetamine. These results parallel those previously obtained with dopaminergic neurons, suggesting that both types of cells lose their sensitivity to amphetamine with repeated injections.
Dual Mobility for Chronic Instability

A dual mobility cup consists of a large, fixed, porous coated acetabular component and a bipolar femoral component (a "tripolar" implant). The cup was developed to reduce the incidence of dislocation in patients at risk of instability who required primary or revision total hip replacement. The currently available long term clinical results indicate that the cup provides stability and is durable in this patient population. Recent new developments of the concept include: 1) an anatomically shaped shell; 2) use of highly crosslinked polyethylene; and 3) a modular shell.
Design analysis of heated atomic force microscope cantilevers for nanotopography measurements

This paper considers the impact of electrical and mechanical design parameters on sensitivity and resolution of heated atomic force microscope cantilevers used for nanoscale topography measurements. A finite-difference simulation calculates heat generation and heat transfer from the cantilever, systematically varying heater impurity doping concentration, thickness, leg width, tip height and heater size. The highly nonlinear temperature-dependent electrical resistance of the doped silicon cantilever governs the cantilever performance and is tightly coupled with the generation and flow of heat in the cantilever, which are in turn governed by cantilever geometry. The topography sensitivity of the heated cantilever is on the order of 10?3 ?V nm?1 at an operating point of ~1 mW and <500 K, and the resolution is on the order of 0.1 nm Hz?1/2. This analysis seeks to enable the rational design of heated atomic force microscope cantilevers for topography measurements.
Heart failure etiology affects peripheral vascular endothelial function after cardiac transplantation.

Abstract OBJECTIVES The goal of this study was to examine the effect of heart failure etiology on peripheral vascular endothelial function in cardiac transplant recipients. BACKGROUND Peripheral vascular endothelial dysfunction occurs in patients with heart failure of either ischemic or nonischemic etiology. The effect of heart failure etiology on peripheral endothelial function after cardiac transplantation is unknown. METHODS Using brachial artery ultrasound, endothelium-dependent, flow-mediated dilation (FMD) was assessed in patients with heart failure with either nonischemic cardiomyopathy (n = 10) or ischemic cardiomyopathy (n = 7), cardiac transplant recipients with prior nonischemic cardiomyopathy (n = 10) or prior ischemic cardiomyopathy (n = 10) and normal controls (n = 10). RESULTS Patients with heart failure with either ischemic cardiomyopathy or nonischemic cardiomyopathy had impaired FMD (3.6 ± 1.0% and 5.1 ± 1.2%, respectively, p = NS) compared with normal subjects (13.9 ± 1.3%, p CONCLUSIONS Peripheral vascular endothelial function is normal in cardiac transplant recipients with antecedent nonischemic cardiomyopathy, but remains impaired in those with prior ischemic cardiomyopathy. In contrast, endothelial function is uniformly abnormal for patients with heart failure, regardless of etiology. These findings indicate that cardiac transplantation corrects peripheral endothelial function for patients without ischemic heart disease, but not in those with prior atherosclerotic coronary disease.
DATA-DRIVEN MAGNETOHYDRODYNAMIC MODEL FOR ACTIVE REGION EVOLUTION

We present a self-consistent, three-dimensional, magnetohydrodynamics model together with time-dependent boundary conditions based on the projected method of characteristics at the source surface (photosphere) to accommodate the observations. The new physics included in this model are differential rotation, meridional flow, effective diffusion, and cyclonic turbulence effects in which the complex magnetic field structure can be generated through the nonlinear interaction between the plasma and magnetic field. This solution, again, is accomplished by including the time-dependent boundary conditions derived from the method of characteristics. This procedure is able to accommodate observations via self-consistent and appropriate data inputs to the boundary. Thus, subphotospheric (i.e., convective zone) effects, through observations, are able to be coupled with the corona. To illustrate this new model, we have employed an observed active region's (NOAA AR 8100) magnetic field measurements from SOHO MDI magnetograms to demonstrate the model's capability. Thus, the evolution of three-dimensional magnetic field, velocity field, and energy transport are shown, thereby enabling us to study the physical mechanisms of AR evolution.
Polymerization in the crystalline state. VIII. Polymerization in N‐carboxy anhydrides of γ‐benzyl glutamate, γ‐methyl glutamate, and ϵ‐carbobenzoxylysine

The kinetics of the solid-state polymerization of the N-carboxy anhydrides (NCA) of the L- and racemic forms of γ-benzyl glutamate (BG), γ-methyl glutamate (MG), and ϵ-carbobenzoxylysine (CL) were studied as a function of temperature and aqueous vapor pressure. The reaction of the L-forms of BG and MG was characterized by an induction period, while the CL derivative reached its maximum polymerization rate at the outset of the reaction. Water vapor had only a minor effect in accelerating the reaction and reducing the chain length of the polypeptides formed. The racemic monomers were found to have different crystal structures from those of the L-isomers and the racemic MG and CL derivatives polymerized much more slowly than the corresponding optically active crystals. All polymers gave diffuse x-ray diffraction patterns. Infrared spectra of the L-polypeptides showed that they were largely in the α-helical form. The polymer derived from the racemic BG–NCA had a content of α-helical material which suggested that it consisted of polypeptides with long blocks of D and L residues.
Feedback stabilization of uncertain systems using a stochastic digital link

We study the stabilizability of uncertain systems in the presence of finite capacity feedback. Motivated by the structure of communication networks, we consider a stochastic digital link that sends words whose size is governed by a random process. Such link is used to transmit state measurements between the plant and the controller. We derive necessary and sufficient conditions for the internal and the external stabilizability of the feedback loop. In accordance with previous publications, stabilizability of unstable plants is possible if and only if the link's average transmission rate is above a positive critical value. In our formulation the plant and the link can be stochastic. In addition, stability in the presence of uncertainty in the plant is analyzed using a small-gain argument. We show that the critical average transmission rate, for stabilizability, depends on the description of uncertainty and the statistical properties of the plant as well as the link.
Interleukin-6 Induces Skeletal Muscle Protein Breakdown in Rats:

In previous studies, interleukin-1 (IL-1) or tumor necrosis factor (TNF) have been demonstrated to augment skeletal muscle protein breakdown in a manner similar to that induced by bacterial endotoxin. This response to IL-1 or TNF was elicited only after they were administered to animals for various periods, as their addition in vitro to incubated muscles from normal untreated rats was without effect. This suggested that IL-1 and TNF may augment muscle proteolysis in an indirect fashion. Serum levels of IL-1, TNF as well as interleukin-6 (IL-6) are all elevated during infection induced by bacterial endotoxin. Both IL-1 and TNF can induce the synthesis of IL-6 by a variety of cells. Because of this, in the present report, the ability of IL-6 to stimulate skeletal muscle protein breakdown was examined. Muscle protein breakdown was evaluated by measuring the release of both tyrosine and 3-methylhistidine by incubated muscles. Pretreatment of rats with IL-6 for 6 hr induced fever and increased the release of both tyrosine and 3-methylhistidine by the extensor digitorum longus muscle. However, IL-6 did not augment muscle proteolysis when muscles from normal untreated rats were incubated in the presence of the cytokine. The data suggest that the acute treatment of animals with IL-6 can augment muscle proteolysis. Whether this response is due to a direct effect of IL-6 on the myocyte or whether it is due to the production of other mediators remains unclear.
Neural network retrieval of wind velocity profiles from satellite data

A method has been developed for retrieval of wind velocity profiles from satellite sounder radiances using a neural network technique. Each wind velocity represents a mean value for a layer approximately centred at that standard height or pressure level. The neural network input vector includes sounder radiances from the Geostationary Operational Environmental Satellite (GOES), plus ancillary information such as latitude and longitude. A set of ‘co-incident’ rawinsonde soundings provide the ‘truth’ data set. In the initial results root mean square errors for the standard levels from 850 to 300 hPa have about the same magnitude as those for current methods such as tracking of moisture features in GOES imagery. As with more traditional methods, the largest root mean square error occurs near the tropopause. Although the results to date appear highly promising, considerable further work is needed before we have an operationally capable technique. Copyright © 2000 Royal Meteorological Society
Effects of Dietary Aflatoxin on Certain Egg Yolk Parameters

Abstract Aflatoxicosis was induced in laying hens by incorporating graded amounts of aflatoxin into a commercial layer ration (0, 1.25, 2.5, 5.0, and 10.0 μg./g. of feed). After four weeks liver size and liver lipid were increased by aflatoxin while egg production and egg size were decreased (P
Immunoassay Detection of Drugs in Racing Horses: Detection of Ethacrynic Acid and Bumetanide in Equine Urine by ELISA

We have raised antibodies and developed one-step enzymelinked immunosorbent assays (ELISA) for the diuretics ethacrynic acid and bumetanide as part of a panel of pre- end post-race tests for high potency drugs in racing horses. These ELISA tests are rapid (completed within one hour), sensitive, and can be read by eye. The ELISA detects ethacrynic acid at s drug concentration for half-maximal inhibition (I-50) of about 2.5 ng/mL for the parent drug. After dosing horses Intravenously with 5 mg ethacrynic acid per horse, the parent drug or its metabolites are detectable in urine for at least 8 hours. The bumetanide ELISA has an 1-50 for the parent drug of about 2.0 ng/mL and will detect bumetanide or its metabolites for about 8 hours in urine after intravenous administration of a 1.7-mg dose per horse. Both antibodies are relatively specific for each drug and do not cross-react with other commonly used diuretics or other acidic compounds often found in post-race equine urine samples. Ethacrynic acid and bumetanide are potent diuretics suspected of being illegally substituted for furosemide in certain racing jurisdictions. Development of these rapid, sensitive, and simple tests for these agents will allow more effective pre- and post-race control of the use of these agents In racing horses. Both tests have recently uncovered several "positives" for these medications in a midwestern racing
Effect of a gluten-free diet on gastrointestinal symptoms in celiac disease

Background: Atypical presentations of celiac disease appear to be at least as common as is the classic presentation of steatorrhea, diarrhea, and weight loss. Objective: We examined the effect of a gluten-free diet on gastrointestinal symptoms in a cohort of US patients with celiac disease. Design: A follow-up survey was conducted in 215 patients who were evaluated at the University of Iowa from 1990 through 1997 as having biopsy-confirmed celiac disease. The systematic survey asked detailed questions regarding gastrointestinal symptoms before and after the institution of a gluten-free diet in the patients, all of whom had been given the same dietary advice. Results: The group consisted of 160 female and 55 male patients. Although diarrhea was the most frequent symptom in untreated celiac disease, steatorrhea occurred in only one-fifth of patients. Other complaints were common, and most responded to gluten exclusion. The benefit of gluten exclusion was equally apparent in men and women. Diarrhea responded in most patients, usually within days, and the mean time to resolution was 4 wk. Many patients had alternating diarrhea and constipation, both of which were responsive to the gluten-free diet. Most patients had abdominal pain and bloating, which resolved with the diet. Conclusions: Celiac disease causes a wide range of gastrointestinal symptoms. Clinicians must have a high level of suspicion to detect the atypical forms of celiac disease. With a gluten-free diet, patients have substantial and rapid improvement of symptoms, including symptoms other than the typical ones of diarrhea, steatorrhea, and weight loss. Am J Clin Nutr 2004;79:669 –73.
Romanov Riches: Russian Writers and Artists under the Tsars – By Solomon Volkov

Russia's rich cultural heritage, especially under the last czars, is beyond dispute, and many books have been devoted to the subject. From the time of Catherine the Great, most Russian rulers patro...
Analysis and design of single-pole transmission structures

Abstract The unguyed single-pole transmission structure is widely used to support transmission lines of up to 345 kV capacity. Most such structures are wood poles, although prestressed concrete poles and tubular steel poles are sometimes used in high decay or high load situations. A number of features combine to make this type of structure an interesting structural analysis and design problem. Whether naturally grown or manufactured, the pole structure is almost always nonprismatic. Wind, ice and snow loads acting alone or in combination are variable and occasionally severe in nature. Poles are slender and the combination of transverse wind load with vertical dead and ice loads often leads to behavior which is geometrically highly nonlinear. The continuous exposure to weather, fungi, accidents, etc. results in structures with capacities that often deteriorate very significantly with time in service. The material properties (strength, stiffness), especially of wood, are highly variable, as are the soil conditions. The configurations of conductors, davit and cross arms, and attachments that are in use vary widely. This large variety of structural shapes plus the necessity of changing the configurations of in situ structures to meet new conductor and clearance requirements prevents the use of only a few designs. Thus rapid ways to assess existing structures and to design new structures are required. Since there are more than 130,000,000 poles currently in use in single-pole and H-frame transmission structures and several million new poles are put into service each year, the design effort related to poles is large. As part of an eight-year effort to develop reliability-based design methods for transmission structures, a correct procedure for analyzing and designing single-pole transmission structures was established. Implemented in program POLEDA (POLE Design and Analysis), this procedure enables unguyed planar single-pole structures of virtually any material and configuration to be rapidly analyzed or designed. The analysis is based on the Newmark numerical technique which, it is shown, in the limit provides an exact solution to the differential equation for large deflections of transversely loaded beams. The four design options provided in POLEDA use the load and resistance factor design (LRFD) format. This permits the user to use current, deterministic, design procedures or to use load and resistance factors based on reliability studies. The program provides the necessary high-quality analysis capability which forms an integral part of reliability-based design. It is being widely adopted by the electric utility industry.
Raman, photoluminescence, and SEM studies of CdS and CdTe films grown by RF sputtering and laser physical vapor deposition

Polycrystalline films of CdS, CdTe, as well as CdS/CdTe heterojunctions grown by RF magnetron sputtering and by pulsed laser physical vapor deposition are studied using the techniques of SEM, photoluminescence (PL), and Raman scattering. By correlating grain sizes and spectral features we have been able to optimize growth temperatures. Optical studies of the buried heterojunction and the spectral response of the cell have led to optimization of post-growth anneal times and layer thicknesses. >
C-terminal truncation of rabbit flavin-containing monooxygenase isoform 2 enhances solubility

Abstract Flavin-containing monooxygenases (FMO) are membrane-associated enzymes contributing to oxidative metabolism of drugs and other chemicals. There are no known structures similar enough to FMO to provide accurate insights into the structural basis for differences in metabolism observed among FMOs. To develop an FMO amenable to crystallization, we introduced mutations into rabbit FMO2 (rF2) to increase solubility, decrease aggregation, and simplify isolation. Alterations included removal of 26 AA (Δ26) from the carboxyl-terminus, His6-fusion to the amino-terminus and a double Ser substitution designed to reduce local hydrophobicity. Only Δ26 FMO variants retained normal activity, increased the yield of cytosolic rF2 and decreased protein aggregation. Δ26 constructs increased rF2 in cytosol in low (from 2 to 13%), and high salt (from 24 to 62%) conditions. His-fusion proteins, while active and useful for purification, did not affect solubility. Δ26 variants should prove useful for identifying conditions suitable for production of an FMO crystal.
Acute toxicity of a complex mixture of synthetic hexachloroethane (HC) smoke combustion products: I. Comparative toxicity to freshwater aquatic organisms

The acute toxicity of a synthetic hexachloroethane (HC) smoke combustion products mixture to nine freshwater aquatic organisms was determined. Synthetic HC smoke combustion products are a complex mixture containing Zn, Cd, As, Pb, Al, CCl4, C2Cl4, C2Cl6, C6Cl6 and HCl. Juvenile fish exposed to this mixture for 96 h included the fathead minnow, bluegill, channel catfish and rainbow trout. Invertebrates tested for 48 h included the neonate water flea, early young amphipod, midge larva and the mayfly larva. The effect of the mixture on the growth of the green alga Selenastrum capricornutum was also studied. The dissolved components of the synthetic HC smoke combustion products mixture were found to be quite toxic to a number of freshwater species, especially the algae, rainbow trout and water flea. A test solution containing only 5.6% of a stock mixture of these components caused both an algistatic and algicidal effect on the alga. The rainbow trout and the water flea had 96- and 48-h LC50s of 2.2 and 9.3% of the stock solution, respectively.
Memory and Hypnosis: A Comparative Analysis of Guided Memory, Cognitive Interview, and Hypnotic Hypermnesia:

This study compared the relative efficacy of four popular methods of memory retrieval: hypnosis, “Guided Memory,” “Cognitive Interview,” and spontaneous free recall. These retrieval methods, tested in an academic setting, were paired with different intake methods, utilizing audio, visual, audio-visual, and reading inputs. All interview sessions, including hypnosis induction, were conducted individually and only free recall (as opposed to forced recall) techniques were used by the interviewers. The number of subjects' correct responses was converted to a percentage of the total of potentially remembered items. These data, through the use of a Treatment o Block ANOVA, showed a statistically significant difference between intake methods but a nonsignificant difference between recall methods, suggesting that guided memory and cognitive interview techniques may be as effective as hypnosis in short term free recall. This study indicates that when contributing cognitive features are extracted, hypnosis by itself...
Suicidal ideation and suicide attempts among Hispanic subgroups in the United States: 1991-1992 and 2001-2002

Objective: To compare the prevalence of suicidal ideation/attempts among Hispanic subgroups in the US in 1991e1992 and 2001e2002, and identify high-risk groups. Method: Data were drawn from the 1991e1992 National Longitudinal Alcohol Epidemiologic Survey (NLAES, n ¼ 42,862) and the 2001e2002 National Epidemiological Survey on Alcohol and Related Conditions (NESARC, n ¼ 43,093), two nationally representative surveys of individuals aged 18 years and older. Results: 1) Puerto Ricans are the Hispanic ethnic subgroup with the highest rates of suicide attempts; 2) 45- to 64-year-old Puerto Rican women are a high-risk group for suicide attempts; 3) Over the 10 year period between the two surveys, the lifetime prevalence of suicide attempts significantly increased among 18- to 24-year-old Puerto Rican women and Cuban men, and among 45- to 64-year-old Puerto Rican men. Conclusion: Hispanics in the US are not a homogeneous group. We identify high-risk groups among Hispanics. Specific interventions for subgroups of Hispanics at high risk for suicidal behaviors may be required.
The RE M E Phases

In the second contribution on the RE M E phases, we enumerate the distinct networks resulting from the stacking in an eclipsed fashion of graphitic and puckered layers. Specifically, we derive all the distinct hypothetical lattices for up to N=7 layers per unit cell for planar (graphitic) sheets, and up to N=10 for slightly puckered layers. For the networks with slightly puckered layers, there can be only an even number of layers/unit cell, N. Additionally, we formulate an empirical rule for network stability: the structure should have either a mirror plane or a twin operation (mirror plane, followed by a color change) bisecting it half-way up the stacking axis. Using these simple principles, from the original multitude of 2N−1 structures for a given N, we are able to significantly narrow down the number of potential combinations. Thus, for N=2, we find two nets, for N=4, one, for N=6, two, for N=8, there are no such viable arrangements, and for N=10, we exclude all but two distinct lattices. We sketch further guidelines to continue the enumeration for higher Ns. We also propose an ‘overlapping' Aufbau, by which more-complex structures are derived from the smaller, basic ones. In the last part, we analyze the eclipsed stacking of diamond-type layers; the resulting networks are analogous (in sequencing) to those determined for slightly puckered sheets. The networks formed from staggered diamond-type layers are briefly discussed in the context of the related SiC polytypes.
Field and Laboratory Evaluation of Cement Kiln Dust as a Soil Stabilizer

A field and laboratory study was conducted to evaluate cement kiln dust (CKD) as a soil stabilizer. The performance of CKD from three different cement manufacturers was compared with that of quicklime. Field-work involved construction of test sections along a rural highway in Oklahoma. Observations were made to compare construction requirements for CKD and lime. Treated soil samples were collected from the field to prepare specimens for unconfined compression testing in the laboratory. In situ testing included dynamic cone penetration testing in the stabilized subbase and falling weight deflectometer testing after completion of the pavement. Chemical testing was conducted to determine the chemical makeup of each dust, and soil-CKD mixtures were tested for pH response. Chemical tests on the CKD and CKD-soil mixtures revealed aspects of the CKD composition that can be correlated with the degree of stabilization. Regarding strength improvements, results showed that CKD from one cement plant performed signifi...
Aortic Valve Disease in Pulmonary Atresia and Major Aortopulmonary Collaterals

Background Aortic valve disease in association with pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals (PA/VSD/MAPCAs) is an extremely rare combination of congenital heart defects. The presence of aortic stenosis or insufficiency or both imposes an additional physiologic burden that complicates the management of PA/VSD/MAPCAs. This report summarizes our experience with 7 patients who underwent surgical repair of this rare combination of defects. Methods This was a retrospective review of patients who had both aortic valve disease and PA/VSD/MAPCAs. Four patients had predominantly aortic stenosis, 2 patients had aortic insufficiency, and 1 had mixed stenosis and insufficiency. Anatomically, this corresponded to a dysplastic trileaflet valve in 4, bicuspid valve in 2, and quadricuspid valve in 1. Results Four of the 7 patients underwent aortic valve surgery at the time of their first operation for PA/VSD/MAPCAs. The remaining 3 patients had aortic valve surgery at subsequent operations. All 7 patients are alive, with a median duration of follow-up of 3 years. One patient has required aortic valve replacement 2 years after repair of an insufficient bicuspid valve. Conclusions This manuscript summarizes our experience with 7 patients who had the rare combination of aortic valve disease and PA/VSD/MAPCAs. Although aortic valve disease has been reported for other conotruncal defects, we believe this is the first report of its presence in association with PA/VSD/MAPCAs.
THE AAPOR CONFERENCE AS A COMMUNICATION MEDIUM

T HE ROLE of scientific conventions in the information system of science has been studied very little, at least in comparison with the attention given to books and journals. This neglect may be explained by the ephemeral nature of what actually takes place at a convention. Books and journals are substantial artifacts of the information system; they can be called up for study at any time. The informal exchanges of information at a convention leave no record-except in the minds of scientists themselves. Two kinds of convention studies are found in the literature on scientific information fow (a comparatively new research area at the intersection of documentation, communication research, and the sociology of science). The summary approach is that of reporting how many scientists in a discipline attended scientific meetings during a period of time, how many papers were presented, what funds were spent on travel, and so on. Such data were reported by Orr, Coyl, and Leeds for meetings of the Federation of American Societies for Experimental Biology.'
Isothiazolidinone heterocycles as inhibitors of protein tyrosine phosphatases: Synthesis and structure–activity relationships of a peptide scaffold

Abstract The structure-based design and discovery of the isothiazolidinone (IZD) heterocycle as a mimic of phosphotyrosine (pTyr) has led to the identification of novel IZD-containing inhibitors of protein tyrosine phosphatase 1B (PTP1B). The structure–activity relationships (SARs) of peptidic IZD-containing inhibitors of PTP1B are described along with a novel synthesis of the aryl-IZD fragments via a Suzuki coupling. The SAR revealed the saturated IZD heterocycle (42) is the most potent heterocyclic pTyr mimetic compared to the unsaturated IZD (25), the thiadiazolidinone (TDZ) (38), and the regioisomeric unsaturated IZD (31). The X-ray crystal structures of 11c and 25 complexed with PTP1B were solved and revealed nearly identical binding interactions in the active site. Ab initio calculations effectively explain the strong binding of the (S)-IZD due to the preorganized binding of the IZD in its low energy conformation.
Exon 19 Deletion Mutations of Epidermal Growth Factor Receptor Are Associated with Prolonged Survival in Non–Small Cell Lung Cancer Patients Treated with Gefitinib or Erlotinib

Purpose: Somatic mutations in the epidermal growth factor receptor (EGFR) have been detected in patients with non–small cell lung cancer (NSCLC) and are associated with sensitivity to treatment with gefitinib or erlotinib. Our study explored the relationship between the two most common types of somatic EGFR mutations, exon 19 deletions and the L858R point mutation, and outcomes of patients following treatment with gefitinib or erlotinib. Experimental Design: Tumor specimens obtained before treatment with gefitinib or erlotinib were analyzed for EGFR mutations. Patients with exon 19 deletion or L858R mutations were identified. The response rate, time to progression, and overall survival were determined for the two groups. Results: We identified 36 patients with NSCLC and an EGFR mutation who were treated with gefitinib or erlotinib. Patients with an exon 19 deletion had a significantly longer overall survival compared with patients with an L858R mutation (38 versus 17 months; P = 0.04). There were also trends toward higher response rate (73% versus 50%) and improved time to progression (24 versus 10 months) for the patients with an exon 19 deletion, although these were not independently significant in a multivariate analysis. A difference in response rate for patients treated with gefitinib compared with erlotinib was also noted [18 of 23 (78%) versus 3 of 9 (33%); P = 0.04]. No obvious difference in time to progression or overall survival was noted between gefitinib- and erlotinib-treated patients. Conclusions: Patients with NSCLC and EGFR exon 19 deletions have a longer survival following treatment with gefitinib or erlotinib compared with those with the L858R mutation. Pooling of greater numbers of patients and completion of prospective trials are needed to further define the predictive and prognostic roles of different EGFR mutations with respect to treatment with gefitinib, erlotinib, and other EGFR inhibitors.
Monitoring the formation of carbide crystal phases during the thermal decomposition of 3d transition metal dicarboxylate complexes.

Single molecule precursors can help to simplify the synthesis of complex alloys by minimizing the amount of necessary starting reagents. However, single molecule precursors are time consuming to prepare with very few being commercially available. In this study, a simple precipitation method is used to prepare Fe, Co, and Ni fumarate and succinate complexes. These complexes were then thermally decomposed in an inert atmosphere to test their efficiency as single molecule precursors for the formation of metal carbide phases. Elevated temperature X-ray diffraction was used to identify the crystal phases produced upon decomposition of the metal dicarboxylate complexes. Thermogravimetric analysis coupled with an infrared detector was used to identify the developed gaseous decomposition products. All complexes tested showed a reduction from the starting M2+ oxidation state to the M0 oxidation state, upon decomposition. Also, each complex tested showed CO2 and H2O as gaseous decomposition products. Nickel succinate, iron succinate, and iron fumarate complexes were found to form carbide phases upon decomposition. This proves that transition metal dicarboxylate salts can be employed as efficient single molecule precursors for the formation of metal carbide crystal phases.
Performance and cost of wet and dry cooling systems for pulverized coal power plants with and without carbon capture and storage

Thermoelectric power plants require significant quantities of water, primarily for the purpose of cooling. Water also is becoming critically important for low-carbon power generation. To reduce greenhouse gas emissions from pulverized coal (PC) power plants, post-combustion carbon capture and storage (CCS) systems are receiving considerable attention. However, current CO2 capture systems require a significant amount of cooling. This paper evaluates and quantifies the plant-level performance and cost of different cooling technologies for PC power plants with and without CO2 capture. Included are recirculating systems with wet cooling towers and air-cooled condensers (ACCs) for dry cooling. We examine a range of key factors affecting cooling system performance, cost and plant water use, including the plant steam cycle design, coal type, carbon capture system design, and local ambient conditions. Options for reducing power plant water consumption also are presented.
A low molecular weight substance purified from human placenta inhibits cAMP-dependent protein kinase and activates protein kinase C

We have purified from human placenta a low molecular mass substance that inhibits cAMP-dependent protein kinase and activates protein kinase C. This protein kinase regulator was purified in three steps: (1) homogenizing placentas in chloroform/methanol and extracting the regulator into water; (2) eluting a strong anion exchange high performance liquid chromatography (HPLC) column with a quaternary gradient; and (3) eluting a reversed-phase HPLC column with a binary gradient. The regulator was found to be highly purified by HPLC, thin-layer chromatography (TLC) and laser desorption ionization mass spectrometry with a molecular mass of 703 Daltons by the latter procedure. The physical and biochemical properties of this protein kinase regulator suggest that it is a phospholipid but it did not co-elute by HPLC or by TLC with any of the known phospholipid activators of protein kinase C.
Nitrogen, phosphorus, and sulfur dynamics in a low salinity marsh system dominated by Spartina alterniflora

In the upper reaches of estuaries, the pulsing of nutrient inputs and salinity occurs on fine temporal and spatial scales. We investigated the supply and exchanges of N, P, and S along a salinity gradient in a Chesapeake Bay subestuary. Interactions among nutrients in surface water, sediment porewater, and shoots of the dominant marsh macrophyte Spartina alterniflora were also examined. The system was characterized by a spatial gradient in nutrient availability, with the low salinity region representing abundant allochthonous nitrogen and phosphorus inputs and minimal sulfur availability. Autochthonous production and consumption of nutrients were most important at the midpoint of the salinity gradient. These patterns were reflected in the N, P, and S content of S. alterniflora over one growing season. This brackish tidal creek system also had a gradient of temporal variability in levels of inorganic nitrogen, phosphorus, and sulfur. The higher salinity portion experienced the damping effect of waters of more constant nutrient composition, whereas the upper portion of the system was characterized by highly pulsed nutrient availability. Interchanges between nutrient pools were apparent throughout the system. Sediment, and even surface-water, concentrations of nutrients seemed to respond to plant root zone oxidation and uptake and release of nutrients. Porewater biogeochemical processes were linked to surface-water nutrient dynamics as well.
Evidence to Support Peer Tutoring Programs at the Undergraduate Level

The present study examined undergraduate peer tutoring in three phases. Phase I qualitatively surveyed students’ perceptions about the effectiveness of tutoring. Phase II examined the usefulness of promoting regular use of services through a tutoring contract. Phase III utilized an archival, quasi-experimental approach to estimate the effect of peer tutoring on students who repeated an undergraduate course and either received tutoring or did not receive tutoring during their second attempt. Results revealed a significant estimated treatment effect, lending support to a causal relationship between tutoring and final course outcomes. Tutoring was especially beneficial for first-generation college students.