cssi/SciSciGPT-SciSciNet huggingface dataset:
Universities and the money fix

Funding woes plague US biomedical researchers. But calls for more funding ignore the structural problems that push universities to produce too many scientists, argues Brian C. Martinson. The current system of biomedical research funding by the US National Institutes of Health is founded on the notion that the more researchers the universities can produce, the better for all concerned. Brian C. Martinson argues that sheer numbers should not be the goal. Instead, existing researchers should be given more time, space and freedom to ask questions in new ways, to take risks, and to innovate. Reducing the intensity of competition for NIH funds is one way of making this happen.
Formation of flavors during extrusion cooking

Abstract Extrusion cooking is a high‐temperature/short‐time process which is ideal for the production of flavor volatiles. However, due to the nature of this process there are many opportunities for these volatiles to be lost. This has led many researchers to study the formation and retention of volatiles during extrusion. This review focuses on the flavor‐related reactions which may occur during extrusion, including their occurrence in various flours and due to the addition of reactive precursors.
Recognition of Spawning Areas by Lake Trout: Deposition and Survival of Eggs on Small, Man-Made Rock Piles

Reproductive success of stocked lake trout (Salvelinus namaycush) in the Great Lakes has been negligible in all of the lakes except Superior. Among the factors which may affect reproduction, the quality of spawning habitat and selection of good habitat by hatchery-origin lake trout are important for the success of population restoration. Stocked lake trout may be unable to recognize small areas of appropriate spawning substrate. The purpose of this study was to identify characteristics of spawning substrate {e.g., depth, substrate size, reef contour) that are important for spawning site selection by lake trout, and to associate these characteristics with egg incubation success. Six rock piles, 4.5 m in diameter, were constructed 80 m from a natural spawning reef. Egg deposition and survival to hatching were measured on and adjacent to the rock piles and on the nearby natural cobble reef. Lake trout spawned on all of the rock piles in 1990 and 1991. Few eggs were collected immediately adjacent to the piles. Egg densities on the piles were two to four times lower than on the natural cobble reef that was much larger in area. These data indicate that spawning site selection by lake trout was influenced by substrate size and location. Egg survival was high in incubators buried in rock piles (38–61%) and natural cobble (27–59%), but low in incubators adjacent to the piles (3–10%) and on sandy substrates (9%). Thus, lake trout detected and spawned on small areas of clean cobble that supported egg incubation. Lake trout will use new areas of substrate even when larger natural areas are available within 100 m. This result indicates that lake trout spawning on harbor breakwalls and man-made rubble piles is due to their attraction to clean substrate rather than the absence of natural substrate nearby.
Does Parental Education have a Moderating Effect on the Genetic and Environmental Influences of General Cognitive Ability in Early Adulthood

Hereditary influences account for a substantial proportion of the variance in many cognitive abilities. However, there is increasing recognition that the relative importance of genetic and environmental influences may vary across different socioeconomic levels. The overall goal of the present study was to examine whether parental education has a moderating effect on genetic and environmental influences of general cognitive ability in early adulthood (age 19.6 ± 1.5). Participants were 5,955 male twins from the Vietnam Era Twin (VET) Registry. Significant effects of parental education on mean level of general cognitive ability scores were found, but a model without moderating effects of parental education on genetic or environmental influences on cognitive scores proved to be the best fitting model. Some, but not all, previous studies have found significant moderating effects; however, no consistent pattern emerged that could account for between-study differences regarding moderating effects on genetic and environmental influences.
Effects of Cryopreservation on Immune Responses

In view of the wide usage of frozen PBMCs as stem cell support following high-dose chemo- and/or radiotherapy, and the pleiotropic activities of tumor necrosis factor-alpha (TNF-alpha), the influences of freezing and radiation on LPS-induced TNF-alpha production by human peripheral blood mononuclear cells (PBMCs) were studied. Frozen PBMCs secreted significantly larger quantities of TNF-alpha than fresh cells. Blocking of endogenous IL-10 by neutralization with anti-IL-10 monoclonal antibody resulted in further augmented and prolonged secretion of TNF-alpha by both the fresh and frozen cells. In contrast, addition of exogenous IL-10 to LPS-stimulated cultures inhibited TNF-alpha secretion. In vitro irradiation had an inconsistent effect on TNF-alpha production by the fresh PBMCs. Taken together, these results suggest that the endogenously hypersecreted TNF-alpha is indirectly responsible for the previously reported elevated IL-1-, IL-6-, and IL-10-secreting capabilities of frozen PBMCs. They also indicate that the TNF-alpha induced IL-10 and then down-regulates the monocytes from further TNF-alpha secretion. Considering the vital role played by TNF-alpha in antimicrobial and antitumor activities, in the immune system, and in the pathogenesis of many acute and chronic diseases, the abilities of frozen cells to produce large quantities of TNF-alpha in response to infectious agents could have profound impact on patients receiving such frozen PBMCs as stem cell support following myeloablative therapies.
Improving the curriculum through the teaching of calculation and discrimination

Abstract The field of computing—including its application by programmers, systems analysts and others—suffers tremendously from a lack of use of formal reasoning in everyday work. The problem can be solved, at least partly, by teaching calculational methods in mathematics and programming in the freshman year, and in such a way that students develop a skill with the methods, and not just a passing understanding. Freshman courses should instil the idea that mathematical techniques can help and should encourage a sense of discrimination, of making judgements on technical matters based on technical concerns. A serious overhaul of the conventional second programming course and the discrete mathematics course along these lines could have a profound impact on the whole computer science curriculum. Moreover, a properly designed course would be beneficial for mathematicians and engineers as well.
Ground contact characteristics of Tai Chi gait.

Abstract Background: To date, no direct measurement has been done that quantitatively characterizes the foot–ground contact during Tai Chi Chuan movements. The goal of this study was to quantify the biomechanical characteristics of foot–ground contact during a Tai Chi gait (TCG), one of the basic but common Tai Chi Chuan movements. Methods: The ground reaction force profiles, center of pressure (COP) and plantar pressure patterns under the stance foot of TCG were directly measured in a sample of 10 healthy young individuals. Results: The medial force reached a peak value of 12 ± 2% body weight (BW) during early stance. The vertical force reached and maintained a peak value of 109 ± 2% BW during single stance, and shifted within a range of 10% and 70% BW during double stance phases. There was a uniformly small rate of loading in all three directions throughout stance. The peak plantar pressure was fairly constant throughout stance in the rear-foot region (maximum value of 0.27 ± 0.07 kPa/kg), but changed from 0 to 0.16 ± 0.04 kPa/kg in the fore-foot region. The peak pressure difference between the fore-foot and rear-foot regions was less than 0.06 ± 0.01 kPa/kg during single stance and the second double stance. The maximum plantar contact area during TCG was 60 ± 9% of the foot area. The foot COP displaced largely during the early and late part of the stance and maintained fairly stationary during single stance. The maximum COP displacement in the medial–lateral direction was 64 ± 8% of foot width. Conclusions: TCG had a low impact force, a fairly evenly distributed body weight between the fore-foot and rear-foot regions, and a large medial–lateral displacement of the foot COP.
Boundary stresses due to impacts from dry granular flows

[1] Field data and laboratory experiments suggest that bedrock wear from debris flows is largely due to particle–bed impacts, rather than solely due to abrasion by sliding, and that the associated bedrock erosion rates are dependent on the particle size distribution in the debris flow. Here we use Discrete Element Method (DEM) simulations with an established contact mechanics model to explore grain-size influences on contact forces associated with particle–bed impacts in sheared granular mixtures. We first compare DEM simulations with experimental observations obtained from shallow granular flows in rotating drums of diameters 0.56 m and 4.0 m. Our simulations reproduce, without parameter tuning, experimentally measured segregation, boundary pressures, and height profiles. We perform additional simulations systematically varying particle size distributions in binary mixtures. We show that local time-averaged boundary pressures in thin flows are essentially the normal component of the weight of the flow, independent of particle size distribution. However, other statistical measures of boundary forces scale with mass-averaged particle size. We demonstrate that this is because individual particle–bed impacts, rather than impacts from multiple particle collisions, dominate the largest contact forces. We show that these largest impact forces vary as the square of grain size and the 1.2 power of impact velocity as predicted from the contact mechanics model underlying the DEM. These results support the particle size dependence of a recently proposed bedrock incision model and suggest that next steps for a predictive bedrock incision model require the statistics of the largest impact velocities.
FGF-2 immunoreactivity in adult rat ependyma and choroid plexus: Responses to global forebrain ischemia and intraventricular FGF-2

Fibroblast growth factor 2 (FGF-2) immunoreactivity (IR) was examined in the ependyma and choroid plexus (CP) of lateral and third ventricles in normal adult rats, as well as in response to transient forebrain ischemia (TFI) and exogenous FGF-2 delivered intraventricularly for several days by osmotic pump. Similar patterns of FGF-2 IR were seen in the CP epithelia of both lateral and third ventricles, as well as in ependymal cells of the third ventricle and along lateral sides of the lateral ventricles. Consistent staining was seen along the apical aspect of epithelial cells facing the cerebrospinal fluid (CSF). Cytoplasmic staining was seen in the absence of ischemia, and was dramatically reduced in response to TFI. FGF-2 treatment followed by TFI resulted in sustained FGF-2 IR within CP and ependymal cells, supporting the idea that these tissues are involved in synthesis and secretion of growth factors into the CSF. In contrast, along the medial sides of the lateral ventricles, adjacent to brain structures such as the hippocampus, consistent staining was seen along the basal aspect of the ependymal cells. We propose that at least some regions of ependyma may function to transport molecules such as FGF-2 directly into the underlying brain parenchyma.
A sufficient condition for invexity

Abstract In nonlinear programming, invexity is sufficient for optimality (in conjunction with the Kuhn-Tucker conditions). In this paper we give a sufficient condition for invexity in nonlinear programming through the use of linear programming.
Estimation of bioconcentration in marine species using structure-activity models

Structure-activity models, which were developed to predict bioconcentration of organic chemicals in freshwater fish, were tested for use with several marine species (Cyprinodon variegatus, Lagodon rhomboides, Crassostrea virginica, Mytilus edulis). Significant linear relationships existed between the bioconcentration factor (BCF) for each marine species tested and the log of the octanol/water partition coefficient (P). The results suggest that freshwater models can be used to predict the BCF of a chemical in marine species, since the slopes of the freshwater models were within the 95% confidence intervals for marine models. Models derived from data on freshwater species were used to calculate BCF values for each of the marine species. The calculated BCF values were compared with the measured BCF values for each marine species and those measured for the fathead minnow (Pimephales promelas). The data indicate that the log BCF can be estimated for the marine species using freshwater models to within one order of magnitude for a minimum of 71% of the chemicals having a range of 3,000,000 in the partition coefficient (1.61 to 6.50 in log P). It appears that models based on data from freshwater species offer the same precision in estimation of BCF values for marine species as for freshwater fish. Good agreement existed between measured and calculated BCF values for both L. rhomboides and M. edulis, whereas the data for C. virginica were more variable and those for C. variegatus were the most variable. Tests indicated that, generally, calculated BCF values overestimate the measured BCF values. Significant linear relationships existed between measured BCF values for P. promelas and each marine species, except M. edulis.
Genetic Basis of Murine Lupus Nephritis

Systemic lupus erythematosus is a generalized autoimmune disease affecting multiple end-organs including the kidneys. Glomerulonephritis is a leading cause of death in lupus, both in patients and murine models that develop disease spontaneously. Genetic mapping studies have uncovered several genetic intervals that confer susceptibility to nephritis both in human beings and in mice. This review surveys the genomic positions of these nephritis susceptibility loci in murine lupus. Currently we know very little about the molecular identities of the culprit genes within these mapped loci and whether these genetic elements contribute to nephritis directly in a renal-intrinsic fashion or indirectly by augmenting the formation of pathogenic autoantibodies. The next decade is likely to witness a significant broadening of our understanding of how different genes and molecules might facilitate end-organ damage in lupus.
Research Note: Influence of β-Agonist on Plasma Concentrations of Growth Hormone in Broiler Chickens on a Low Plane of Nutrition

The effect of the chronic administration of a beta-agonist (L-640,033; donated by Merck, Sharp and Dohme, Research Laboratories, Rahway, NJ) on both the plasma concentration of growth hormone (GH) and the episodic pattern of GH secretion was examined. Administration of .25, 1.0, or 4.0 ppm beta-agonist in the diet for only 3 to 5 days did not affect the overall mean plasma concentration of GH. These treatments also did not influence the frequency of GH secretory pulses. However, the amplitude of the GH secretory pulses was reduced. In contrast, administration of 1.0 ppm beta-agonist for the 10 to 12-day period increased the mean plasma concentration of GH, the amplitude of the GH secretory pulses, the basal (between pulses) plasma concentration of GH, and the interpeak interval. No effect of in vivo GH secretion was found with .25 ppm beta-agonist treatment for 10 to 12 days. Chicks receiving 4.0 ppm beta-agonist for 10 to 12 days had GH secretory pulses with increased amplitude, but no other differences in GH secretory characteristics were observed.
Pity the spouse! Depression within marriage

The literature on depression in marriage and the effects of depression on the patient's spouse is reviewed. Current treatments for depression frequently do not result in long-term recovery. Relatives experience a considerable burden but their needs are often ignored. Typically, they receive very little information from professionals about the patient's illness or how to cope with the difficulties they face. Marital difficulties are sometimes present and may either result from or contribute to one partner's depression. However, problems of an interpersonal nature are usually not addressed once clinical improvement has been achieved. Psychosocial interventions are used only following several relapses. The need for broader assessment and outcome criteria is emphasized. Long-term recovery may be more likely if interventions are directed at the various problems which exist, rather than concentrating solely on symptom relief. The methods used in the schizophrenia intervention studies and and with “normal” couples may be applicable when one partner is depressed. The few studies which have employed marital therapy as a treatment for depression, either alone or in combination with other therapies, show promising results. Further research is needed to ascertain which approach or combination of approaches is most successful in achieving long-term recovery in depression.
Phage display extends its reach

Proteins that could not be displayed on the surface of phage are now amenable to this powerful selection technology.
Conclusions from the Characteristic Curves of Photographic Plates, Minimum Effect of Grain*

By a consistent argument, based on the characteristic curves of photographic plates, the optimum conditions for the following spectrographic problems are derived: weak emission line without background; weak absorption line; weak emission line on a given continuous background; prefogging; measurement of relative intensities. The effect of the grain on the resolving power is minimized by averaging over the length of the line. This technique gives to the very sensitive plate (Kodak type I-O), in spite of its coarse grain, the same high resolving power as that of a very fine grain plate which requires a 90 times longer exposure.
The effect of polyethylene windows of standard absorption cells on the infrared spectra of vapours

Abstract It is shown that standard absorption cells for vapors or gases which are equipped with polyethylene windows must be used with caution since the vapor of many compounds diffuses spontaneously into the polyethylene once the compound has been filled into the cell. The resulting enrichment of the compound in the polyethylene windows gives rise to spectra which are superpositions of the spectra of the molecules entrapped in the polymer and of the molecules of the vapor phase. Because the frequencies of the vibrational transitions of the molecules entrapped in the polyethylene often undergo frequency shifts (“solvent shifts”), additional, spurious bands may appear in the spectrum and/or changes in the apparent contours of the rotation—vibration branches may take place.
Raman spectroscopy with a fiber-optic probe

Abstract Considerations affecting the use of fiber-optic components in Raman measurements for quantitative analysis are described. Bidirectional single-fiber probe systems and a unidirectional multi-fiber probe are compared. Results are given for a system employing a 1 × 6 bifurcated probe. In situ monitoring of a reaction for formation of a conducting polymer, polypyrrole, is described. A spatial averaging advantage for the fiber-optic system in measurements on solid samples is described, and results for some purine and pyrimidine mixtures are reported.
Hacroscopic Defects in Epitaxial Silicon on Simox and in Annealed SIMOX

Epitaxial silicon layers of 5¼m were grown on SIMOX wafers. The dislocation density decreases by more than an order of magnitude as a function of distance away from the buried oxide. Shallow pits (about 0.5 urn deep and several um wide) are observed on the epitaxial layer with a density of 1-2 mm2. Their density did not change with various processing variations. A search for the origin of the pits by transmission electron microscopy reveals that they may be associated with regions of irregularly thin and sometimes missing buried oxide, which appear after the usual high temperature SIMOX annealing step. These defective regions in the buried oxide appear to initiate twinned growth in the epitaxial silicon, and are associated with pits at the top epitaxial silicon surface.
Local thrombolysis in the treatment of thrombosed arteries, bypass grafts, and arteriovenous fistulas.

Abstract We reviewed the results, systemic effects, and complications associated with the selective infusion of low-dose streptokinase in 151 patients. Successful thrombus lysis was achieved in 78% of atherosclerotic thrombotic occlusions less than 30 days old, in 81% of postprocedural occlusions less than 14 days old, and in 87% of patients with thrombosed arteriovenous fistulas no more than 4 days old. During the first 12 hours of treatment 81% to 84% of patients had >50% decrease in plasma fibrinogen levels and 100% showed the same decline after 24 hours of treatment. The thrombin time was prolonged to at least 1½ times the control thrombin time in 33% to 42% of patients measured at 4 hours of therapy and in 93% to 97% of patients measured at 24 hours of treatment. Fifteen patients (9.9%) had major complications. Eleven of these had hemorrhagic complications, two had significant distal emboli, one had a thrombosed brachial artery, and one had a false aneurysm at the catheter entry site. We have found that selective low-dose streptokinase is effective in the treatment of acute and chronic thrombotic occlusions and is a useful adjuvant to vascular reconstruction or percutaneous transluminal angioplasty. Although the local infusion dose is substantially lower than the usual systemic dose, a systemic lytic effect was seen in all patients. Hemorrhagic complications occurred despite customary precautions. (J VASC SURG 1985;2:406-14.)
The role of temperature in determining distributions and coexistence of three species of Plestiodon

Abstract The Common Five-Lined Skink ( Plestiodon fasciatus ), Southeastern Five-Lined Skink ( P. inexpectatus ), and Broadheaded Skink ( P. laticeps ) are all found in forested ecosystems of the southeastern United States and occur in apparent sympatry. No aspect of their ecology has been quantitatively shown to be different. Differences in their natural history, such as northern extent of geographic range, observations of differences in habitat preference, and differing physiological responses to temperature, implicate the thermal environment as a potential niche dimension by which these organisms partition resources. Here we show that the northernmost extent of each species' range can be adequately discriminated by temperature extremes and that their preferred habitats differ in canopy cover, mean temperature, and daily maximum temperatures. These differences are supported by observations in the field. Based upon these findings and observations, we conclude that these species may be able to exist in such close proximity due to differences in their thermal niche, particularly the two like-sized species, P. fasciatus and P. inexpectatus. P. laticeps is a much larger lizard as an adult and functionally coexists with its congeners, potentially by partitioning resources along a different axis.
PROCESSES AND REASONING IN REPRESENTATIONS OF LINEAR FUNCTIONS

This study examined student actions, interpretations, and language in respect to questions raised regarding tabular, graphical, and algebraic representations in the context of functions. The purpose was to investigate students’ interpretations and specific ways of working within table, graph, and the algebraic on notions fundamental to a conceptualization of linear functions. Through a case study method which investigated individual representations and student articulations within them, the study revealed that students can make a transition from a given representation of linear function to another and yet demonstrate limited understanding of linear functions.
Thin Film Nanoelectronic Probe for Protein Detection

There are many biological macro-molecules such as nucleic acids, lipids, carbohydrates and proteins. While each of them plays a vital (and interesting) part in life but there is something special about the proteins. Proteins are the key link between the processes of information and replication that take place on a genetic level and the infrastructure of living features. Understanding the properties of proteins is the key to understanding the spark of the life. In this paper we describe our study of various electrical properties of protein when performing measurements at the nanoscale. To achieve this goal we designed and fabricated a nanoelectronic probe. This nano structure consists of four thin film layers. There are two conductive layers and an insulative layer in between. There is also a protective oxide layer as the top most layer. This layer is to prevent the exposure of conductive electrodes to the solution. Underneath the bottom electrode, there is another oxide layer, which can be a thermally grown oxide. This layer insulates the first electrode from the substrate. In this study, while we use non-specific detection of streptavidin protein as a proof of concept, we emphasize that the findings of this study can be extended to specific detection of target proteins, where in this case a specific probe molecule would also be immobilized on the sensor surface.
Enzymes of D-fructose catabolism in species of Beneckea and Photobacterium.

Cell-free extracts of strains representative of the genera Beneckea and Photobacterium catalyzed a P-enol-pyruvate dependent phosphorylation of d-fructose. The resulting product, fructose-1-P, was converted to fructose-1,6-P2 by 1-P-fructokinase. Both activities were inducible, being present in d-fructose-grown cells and reduced or absent in d-gluconate- (or succinate-) grown cells.
The dawn of terascale computing

The digital revolution, far from abating, continues with even greater intensity in new applications in health, media, social networking, and many other areas of our lives. These applications will require revolutionary improvements in speed and capacity in future microprocessors so that they can process terabytes of information with teraflops of terascale computing power. Tera is not an exaggeration: trillions of hertz and trillions of bytes will be needed. In a terascale world, there will be new processing capabilities for mining and interpreting the world's growing mountain of data, and for doing so with even greater efficiency. Examples of applications are artificial intelligence in smart cars and appliances and virtual reality for modeling, visualization, physics simulation, and medical training. Many other applications are still on the edge of science fiction. In these applications, massive amounts of data must be processed. Three-dimensional (3-D) images in connected visual computing applications like virtual worlds can include hundreds of hours of video, thousands of documents, and tens of thousands of digital photos that require indexing and searching. Terascale computing refers to this massive processing capability with the right mix of memory and input/output (I/O) capabilities for use in everyday devices, from servers to desktops to laptops.
Diesel soot: Mutation measurements in bacterial and human cells

Abstract Both hot pipe and dilution chamber samples of the exhaust from a diesel (Oldsmobile 350) engine have been collected, extracted with methylene chloride and those extracts have been tested for mutagenicity in forward mutation assays in human lymphoblasts and S. typhimurium . In the absence of a metabolic activation system, the extract was significantly mutagenic to the bacteria in the range of 0 to 30 μg/ml, but introduced no mutations in human cells at concentrations up to 200 μg/ml under the same conditions of assay medium. However, when assayed in the presence of a postmitochondrial supernatant derived from rat liver, the the soot extracts were significantly mutagenic to both bacteria and human cells in the range of 50–100 μg/ml. Fractionation of the soot extract on the basis of polarity by sequential elution from a silicic acid column permitted concentration of the mutagenic activity in the alkane/toluene eluate, as determined by bacterial assays. Preliminary characterization of this fraction and preliminary studies of pure compounds leads us to suspect the alkyl substituted phenanthrenes as representing at least a significant fraction of the mutagenic activity of this alkane/toluene eluate.
An Anticoincidence-Shielded Ge(Li) Gamma-Ray Spectrometer for High Sensitivity Counting

An anticoincidence-shielded Ge(Li) gamma-ray spectrometer for high sensitivity counting is described. The system consists of a 20 cc coaxial diode centered inside a 26" diameter by 24" thick plastic phosphor. The source is placed inside the shield and both the coincidence and anticoincidence spectra are recorded simultaneously. The anticoincidence shield reduces the 137Cs Compton edge by a factor of 7.5 to provide a peak to Compton edge ratio of 150:1 without reducing the photopeak efficiency by more than 3%. This system also provides a two to fourfold lower natural radionuclide background than similar sized diodes.
Thermo-photo-voltaic energy conversion

The concept of a thermo-photo-voltaic (TPV) energy converter is introduced and the device compared with thermoelectric and thermionic converters. Features of the TPV converter are that the entire device is kept at room temperature; potential power densities on the order of 10 w/cm2, and potential conversion efficiencies of 30 per cent are possible. Considerations for TPV converter design are presented and compared with solar cells. Use of geometry and thin-film optical filters to improve efficiency is discussed. For a germanium converter operating with a hot source in the neighborhood of 1600°C a p-i-n structure with the absorption taking place in the intrinsic base region is shown to give maximum efficiency. A measured efficiency of 4.23 per cent on an experimental converter with 282 mw/cm2incident energy has been achieved.
Radiation Patterns For Explosively‐Loaded Axisymmetric Cavities In an Elastic Medium: Analytic Approximations and Numerical Results

Summary. A combination of analytic solutions and numerical computations has been used to obtain the low-frequency, far-field P- and S-wave radiation patterns from Heaviside-loaded ellipsoid cavities of fixed volume and varying eccentricity (including the sphere and the finite cylinder) in an unbounded elastic solid. Results show that as the spherical cavity becomes a prolate ellipsoid, S-waves are radiated with strength proportional to the increasing aspect ratio (AR) (major axis/minor axis). With large aspect ratios (AR > 10) both P- and S-wave radiation strengths approach asymptotically a limit for which the maximum P-wave amplitude is twice as large as the maximum S-wave amplitude, irrespective of Poisson's ratio. A representation of the radiation pattern is obtained whose mathematical form can be interpreted as due to the action of a centre of dilatation plus a vector linear dipole, both appropriately weighted. the weights are nonlinear functions of AR. On the basis of numerical results, we have obtained an approximate formula that relates those weights to AR. the radiation patterns thus obtained are in excellent agreement with the experimental results reported by Gupta & Kisslinger. the results may be of some importance to the investigation of explosions in non-spherical cavities and in the study of the origin and mechanisms of volcanic (explosive) earthquakes.
Magnetic particle doping for anisotropic matrix materials in active fiber composites

Active Fiber Composites (AFCs) are composed of uniaxially aligned piezoelectric fibers embedded in a polymer matrix. Two interdigital surface electrodes deliver the required driving voltage. A new concept for anisotropic matrix materials in AFCs has been successfully introduced. The matrix material is doped with ferromagnetic, electrically- conductive particles. The particles are locally aligned during AFC manufacturing by magnetic fields and create an electrically-conductive path between the electrodes and the surface of the piezofibers. The new method allows for more flexibility in the design and processing of AFCs and should lead to reduced driving voltages for AFCs. A manufacturing rig for magnetic particles AFCs (mpAFCs) has been designed and fabricated. A materials system has been optimized and processing methods for production of mpAFCs were developed. Several mpAFCs have been successfully manufactured and characterized. Actuation authority of mpAFCs was investigated and compared to standard AFCs.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Near-infrared (NIR) emitter/detector probe for sensing buried objects and land mines

The detection of landmines and buried objects requires methods that can cover large areas rapidly while providing the required sensitivity to detect the optical and spectroscopic contrasts in soil properties that can reveal their presence. These conditions on contrast and coverage can be met by capturing images of the soil at wavelengths which are sensitive to the properties modified by the presence of buried objects. In this work we investigate both NIR scanning methods which may have some utility for the detection problem. For the scanning method, we acquire data point-by-point over a two- dimensional grid with a single emitter/detector probe. The soil (or sand) above a shallow buried object can be differentiated from the surrounding soil by detecting the difference in relative water content. Moist soil absorbs more near-infrared (NIR) incident light than dry soil. A light- emitting diode (LED) operating at 900 nm and a photodiode sensitive to NIR radiation formed the emitter/detector (ED) probe used in this study. The ED probe was mounted side-by- side and scanned over a surface in a two-dimensional grid as readings were collected point-by-point. The results indicated that this simple NIR emitter/detector probe discriminated between soils of varying water contents with an imaging resolution of 4 millimeters. To illustrate how imaging techniques can be used in this application, the fluorescence image of a landmine casing is presented. The results illustrate the potential of these two approaches for detection of landmines and buried objects.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Protein kinase CK2 contributes to diminished small conductance Ca2+-activated K+ channel activity of hypothalamic pre-sympathetic neurons in hypertension

Small conductance calcium-activated K(+) (SK) channels regulate neuronal excitability. However, little is known about changes in SK channel activity of pre-sympathetic neurons in the hypothalamic paraventricular nucleus (PVN) in essential hypertension. SK channels, calmodulin, and casein kinase II (CK2) form a molecular complex. Because CK2 is up-regulated in the PVN in spontaneously hypertensive rats (SHRs), we hypothesized that CK2 increases calmodulin phosphorylation and contributes to diminished SK channel activity in PVN pre-sympathetic neurons in SHRs. Perforated whole-cell recordings were performed on retrogradely labeled spinally projecting PVN neurons in Wistar-Kyoto (WKY) rats and SHRs. Blocking SK channels with apamin significantly increased the firing rate of PVN neurons in WKY rats but not in SHRs. CK2 inhibition restored the stimulatory effect of apamin on the firing activity of PVN neurons in SHRs. Furthermore, apamin-sensitive SK currents and depolarization-induced medium after-hyperpolarization potentials of PVN neurons were significantly larger in WKY rats than in SHRs. CK2 inhibition significantly increased the SK channel current and medium after-depolarization potential of PVN neurons in SHRs. In addition, CK2-mediated calmodulin phosphorylation level in the PVN was significantly higher in SHRs than in WKY rats. Although SK3 was detected in the PVN, its expression level did not differ significantly between SHRs and WKY rats. Our findings suggest that CK2-mediated calmodulin phosphorylation is increased and contributes to diminished SK channel function of PVN pre-sympathetic neurons in SHRs. This information advances our understanding of the mechanisms underlying hyperactivity of PVN pre-sympathetic neurons and increased sympathetic vasomotor tone in hypertension. Small conductance calcium-activated K(+) (SK) channels, calmodulin, and protein kinase CK2 form a molecular complex and regulate neuronal excitability. Our study suggests that augmented CK2 activity in hypertension can increase calmodulin (CaM) phosphorylation, which leads to diminished SK channel function in pre-sympathetic neurons. Diminished SK channel activity plays a role in hyperactivity of pre-sympathetic neurons in the hypothalamus in hypertension.
Thoughts on irritant contact dermatitis

An attempt is made to formulate some kind of working hypothesis concerning the pathophysiology, clinical appearance and treatment of irritant contact dermatitis. Acute irritant dermatitis may he caused by one single overwhelming external exposure of comparatively short duration. It is usually accidental and therefore recognized early as cause and effect. Chronic irritant dermatitis may be the result of a too early repetition of one impairing factor (chronic irritant dermatitis ‘traumiteration’ type), but is more commonly the result of the influence of a variety of stimuli, each starting to be active before recovery from the foregoing stimuli has been completed (chronic irritant dermatitis ‘summation’ type). By repetition of the same stimulus, or by a combination of varying stimuli, the degree of impairment surpasses a critical level, in consequence of which a clinical disease (irritant contact dermatitis) ensues. This clinical disease, however, is only ‘the tip of the iceberg’. Such stimuli may be chemical, mechanical and/or climatic. To find out which are the harmful factors requires a detailed case history about the patient's work, habits and hobbies, thus enabling him to avoid as many damaging exposures as is practical, and hence reducing the sum of causative factors. A number of causative factors are enumerated. The article is intended to be a catalyst to promote discussion on this subject.
Applications of Multiple-Scan Interferometry to the Measurement of Infrared Spectra

An interferometer can be used to measure infrared spectra. The instrument has no slits, and therefore has a relatively high light-gathering ability. It is also not necessary to disperse polychromatic radiation. The signal-to-noise ratio obtained is consequently high and can be further increased by multiple scanning and coherent addition of information, so that a highly sensitive instrument is available for the measurement of infrared spectra. The interference spectrometer is particularly well suited for the examination of infrared radiation of very low intensity, and has been used to measure infrared absorption, reflection, and emission spectra of a wide variety of materials. Some examples of applications are presented and discussed, including the measurement of infrared emission spectra of minerals and rock specimens and the analysis of the effluent stream of a gas chromatograph.
Mechanistic studies on the poly(4-tert-butoxycarbonyloxystyrene)/triphenylsulfonium salt photoinitiation process

Studies on the poly(4-tert-butoxycarbonyloxystyrene)/triphenylsulfonium salt (TBOC resist) photoinitiation process show strong evidence for a dual photoinitiation process. Photolysis studies on the relative quantum yields and also the ratios for in-cage versus cage-escape sulfide show that the TBOC polymer behaves differently from other polymers and likely sensitizes the decomposition of some of the triphenylsulfonium salt. Also the TBOC resist shows photoactivity at 300 nm, where the polymer absorbs but the triphenylsulfonium salt has only very weak absorbance, which suggests that the sensitization process is initiated by the polymer. However the fact that substantial amounts of in-cage products are also formed for photolysis of the TBOC resist, implicates a direct photodecomposition of the triphenylsulfonium salt. Fluorescence quenching studies on TBOC resist films show that the sensitization proceeds by electron transfer from the singlet excited state of the TBOC polymer and that a mainly static quenching mechanism is involved. The photoinitiation of the TBOC cleavage reaction proceeds by a dual initiation pathway which involves both the excited state of the polymer and the excited state of the triphenylsulfonium salt.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Effects of microphysical drop size distribution on tornadogenesis in supercell thunderstorms

[1] Idealized simulations of tornadogenesis in supercell storms are performed using a grid of 100 m spacing. The cold pool intensity and low-level storm dynamics are found to be very sensitive to the intercept parameters of rain and hail drop size distributions (DSD). DSDs favoring smaller (larger) hydrometeors result in stronger (weaker) cold pools due to enhanced (reduced) evaporative cooling/melting over a larger (smaller) geographic region. Sustained tornadic circulations of EF2 intensity are produced in two of the simulations with relatively weak cold pools. When the cold pool is strong, the updraft is tilted rearward by the strong, surging gust front, causing a disconnect between low-level circulation centers near gust front and the mid-level mesocyclone. Weaker cold pool cases have strong, sustained, vertical updrafts positioned near and above the low-level circulation centers, providing strong dynamic lifting and vertical stretching to the low-level parcels and favoring tornadogenesis.
Improving the care for myocardial infarction: editor's perspective.

The field of outcomes research rigorously searches for opportunities to improve the delivery of health care. The general approach is to carefully describe outcomes—including survival, resource utilization (including hospitalization and treatments over time) and health status—and to examine the source of variations in these outcomes.1 This approach is different from the deductive reasoning used by basic scientists, in which they presume that there is a causal association between a mechanism of disease and test an a priori hypothesis to confirm their theory. Rather, outcomes researchers often follow a more inductive process, whereby outcomes are observed and the presumption is that a myriad of factors contribute, to varying degrees, to the observed outcomes. An example of a good outcomes research study is one that defines a clinically important group of patients, at a distinct point in their care (eg, at the time of an acute myocardial infarction), and systematically assesses a clinically important outcome to describe a broad range of determinants of observed outcomes, including patient-related factors, disease severity, treatment factors, and environmental or structural determinants of outcomes. By identifying important and actionable characteristics associated with outcomes, outcomes researchers can then design interventions to address these characteristics with the goal of improving care and outcomes. The journal Circulation: Cardiovascular Quality and Outcomes is a leading forum for the promotion of the most important science to support the scientific discourse of …
Good or bad for the Jews? moving beyond the continuity debate

Historiquement, la sociologie des juifs aux Etats-Unis - et plus particulierement la sociologie des chercheurs juifs - s'est focalisee sur la question de la survie de la communaute juive, l'ensemble des themes abordes, que ce soit la religion, l'economie, l'identite ou la famille, ayant ete interpretes a travers le prisme de l'opposition assimilation/continuite. Mettant en perspective le role des chercheurs juifs impliques dans l'etude de leur propre communaute, l'A. discute notamment de l'influence de cette position particuliere sur les resultats et l'orientation theorique de leurs recherches. Il suggere que si les chercheurs juifs ne s'orientent pas vers d'autres interrogations que celles induites par la peur de l'assimilation - des questions centrees sur la diversite des experiences des Juifs -, l'approche sociologique des Juifs d'Amerique risque de se tenir a l'ecart de la diversite des debats sur l'ethnicite et sur les tendances religieuses de la societe americaine contemporaine.
Copolymerization of ethylene and propylene catalyzed by novel magnesium chloride supported, vanadium‐based catalysts

Two novel magnesium chloride supported, vanadium-based Ziegler–Natta catalysts with 9,9-bis(methoxymethyl)fluorene and di-i-butyl phthalate as internal donors were prepared and used in the copolymerization of ethylene and propylene. The catalytic behaviors of these catalysts were investigated and compared with those of traditional magnesium chloride supported, vanadium-based catalysts without internal donors. Differential scanning calorimetry, gel permeation chromatography, and 13C-NMR spectroscopy analysis were performed to characterize the melting temperatures, molecular weights, and molecular weight distributions as well as structures and compositions of the products. The copolymerization kinetic results indicated that the novel catalyst with 9,9-bis(methoxymethyl)fluorene as an internal donor had the highest catalytic activity and optimal kinetic behavior in ethylene–propylene copolymerization with an ethylene/propylene molar ratio of 44/56. Low-crystallinity and high-molecular-weight copolymers were obtained with these novel magnesium chloride supported, vanadium-based catalysts. The reactivity ratio data indicated that the catalytic systems had a tendency to produce random ethylene–propylene copolymers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The r.f.-only-mode event for ion-chemistry studies in fourier transform mass spectrometry: the reactions of propene and cyclopropane radical cations with neutral ethene

Abstract The C5H10 adduct ions from the two highly exothermic reactions of propene (C3H6) radical cations with neutral ethene (C2H4) and cyclopropane radical cation with ethene were isolated and detected by incorporating an r.f.-only-mode event into the FTMS experimental sequence. These adducts, which cannot be observed under the low-pressure conditions of the normal FTMS experiment, were characterized by comparing their bimolecular reactivity with 1,3-butadiene (C4H6) with that of C5H10 ions formed by ionization of reference compounds. The C9H16 adducts that originate from all the sources studied here have similar structures that fragment to give product ions of nearly identical relative abundances. Small but real differences are found in the rate constants for most of these reactions, and the differences are interpreted to signify different structures for the adducts that are formed in the actions of ethene with the propene and cyclopropane radical cations. In the case of the propene radical cation reaction, the final product is the highly stable 2-methyl-2-butene radical cation.
Trimeric silver(I) pyrazolates with isopropyl, bromo, and nitro substituents: Synthesis and characterization of {[3,5-(i-Pr)2Pz]Ag}3, {[3,5-(i-Pr)2,4-(Br)Pz]Ag}3, and {[3,5-(i-Pr)2,4-(NO2)Pz]Ag}3

Abstract Trimeric Ag(I) adducts of 3,5-di(isopropyl)pyrazole, 3,5-di(isopropyl),4-bromopyrazole, and 3,5-di(isopropyl),4-nitropyrazole have been synthesized by reacting the corresponding pyrazoles with silver(I) oxide. They have been characterized by X-ray crystallography as well as NMR and IR spectroscopic methods. Both {[3,5-(i-Pr)2Pz]Ag}3 and {[3,5-(i-Pr)2,4-(Br)Pz]Ag}3 exist as pairs of trimers with weak Ag–Ag contacts, whereas {[3,5-(i-Pr)2,4-(NO2)Pz]Ag}3 exists as trimers in the solid state with no inter trimer Ag–Ag contacts.