cssi/SciSciGPT-SciSciNet huggingface dataset:
Threshold Stress Criterion in New Wheel/Rail Interaction for Limiting Rail Damage Under Heavy Axle Loads

This paper presents a qualitative discussion of the effects of increasing new wheel-rail contact stresses on the degree of damage to the rail due to heavy axle loads. The importance and need of heavy axle loads and its relationship to rail damage as a result of the increasing wheel-rail contact stresses is discussed. Various mechanisms of energy absorption/losses due to free rolling and modes of rail damage are presented. The concept of threshold stress is duscussed and analyzed. It is indicated that new wheel-rail profiles, which will achieve contact stresses below the threshold stress, will enable the U.S. railroads to carry heavy axle loads without serious future damage to the rails. It is concluded that a satisfactory solution for maintaintaining rail integrity under heavy axle loads is possible with proper design accompanied with laboratory experimentation for the new steels as they may be used in the rails.
Free-Space Optical MEMS

Microelectromechanical systems (MEMS) technology enables the creation of micro-optical elements that are inherently suited to cost-effective manufacturability and scalability because the processes are derived from the very mature semiconductor microfabrication industry. The inherent advantages of applying microelectronics technology to silicon micromechanical devices, including optical MEMS, were presented in 1982 by Petersen in the now-classic paper, “Silicon as a mechanical material.” [1] The ability to steer or direct light is a key requirement for free-space optical systems. In the 20 years since Petersen’s silicon scanner,[2] the field of optical MEMS has seen explosive growth.[3,4] In the 1980s and early 1990s, displays were the main driving force for the development of micromirror arrays. Portable digital displays are now commonplace, and head-mount displays are also commercially available. In the past decade, telecommunications have become the market driver for optical MEMS. The demand for routing ever-increasing Internet traffic through fiberoptic networks pushes the development of both digital and scanning micromirror systems for large port-count, all-optical switches. In the health care arena, scanning optical devices promise low-cost, optical cross-sectioning endoscopic microscopy for in vivo diagnostics.
Incorporation of radiocopper into ceruloplasmin in normal subjects and in patients with primary biliary cirrhosis and Wilson's disease

Abstract The kinetics of the incorporation of intravenously or orally administered radiocopper into ceruloplasmin have been studied in 8 normal subjects and in 8 patients with hepatic copper overload states (6 with primary biliary cirrhosis and 2 with Wilson's disease). After 0.8 days the radiocopper content of ceruloplasmin in serum was negligible in the patients with Wilson's disease, whereas it was appreciable in the remaining subjects. Total incorporation of radiocopper into ceruloplasmin was calculated by deconvoluting plasma curves of radiocopper in ceruloplasmin with the plasma disappearance curve of intravenously administered radioiodinated ceruloplasmin, and integrating the derived function. In normal subjects incorporation of radiocopper into ceruloplasmin was reduced by approximately 50% when the isotope was given orally rather than intravenously. Plots of the curves of total incorporation of radiocopper into ceruloplasmin against time revealed components which were approximately linear between 2 and 7 days. Extrapolation of these components to zero time yielded positive intercepts with the ordinate, which were relatively smaller in the patients with primary biliary cirrhosis than in the normal subjects. It is concluded: (1) measurements of incorporation of radiocopper into ceruloplasmin can be used to distinguish between two hepatic copper overload states; (2) approximately 50% of orally administered radiocopper is not absorbed; (3) copper is incorporated into ceruloplasmin by at least two different pathways, a slower route which probably involves initial equilibration with a hepatic storage pool, and a more rapid route which presumably bypasses this pool; and (4) incorporation of radiocopper into ceruloplasmin via the more rapid pathway is impaired in primary biliary cirrhosis.
Elevated temperature deformation behaviour of alpha-beta brass bicrystals

Elevated temperature deformation behaviour of alpha-beta brass was investigated by using a model system at temperatures just below the order-disorder transformation temperature (Tc) of beta. Although the deformation mode at these temperatues is very similar to that at room temperature, grain boundary sliding in beta becomes an important mode of deformation at low strain rates.
Late Pleistocene galls from the La Brea Tar Pits and their implications for cynipine wasp and native plant distribution in southern California

Abstract Thirteen intact cynipine galls (Cynipidae) are identified from the significant late Pleistocene locality of Rancho La Brea, mostly within the range of approximately 30,000 to 48,000 14 C yr BP. Late Cenozoic cynipids have a poor fossil record; it is thus of great interest that the provisional dates for this fossil gall collection establish that these insects and their hosts were an important part of the late Pleistocene ecosystem in and around Rancho La Brea. Cynipine host specificity both verifies, as well as augments, the proportionally low record of plants recovered at Rancho La Brea in comparison to records of mammals, birds, and other fauna. Because galler and hosts represent extant species, their climate and habitat restrictions offer a good basis for making paleoecological inferences. In particular, they imply that many of the diverse habitats found in California today, or, at least plant associations with similar environmental restrictions, some presently a distance from the Rancho La Brea Tar Pits, existed in the vicinity of this locality during the late Pleistocene. This material also includes previously undescribed species, several of which are morphologically similar to extant comparative material that exhibits a “jumping” behavior, previously believed to be unique to Neuroterus saltatorius Edwards.
Behavior Intervention for Students with Externalizing Behavior Problems: Primary-Level Standard Protocol

This article examined the efficacy of a primary-level, standard-protocol behavior intervention for students with externalizing behavioral disorders. Elementary schools were randomly assigned to treatment (behavior intervention) or control (business as usual) conditions, and K-3 students were screened for externalizing behavior risk status. The final sample included 7 treatment schools (n = 44 students) and 6 control schools (n = 26 students). Results of multilevel models showed that students with externalizing behavior in the treatment schools had significantly lower levels of problem behavior than those in the control schools. A positive but statistically nonsignificant treatment trend was observed for increased on-task behavior. No effects were observed for academic skills. The positive effects of the behavior intervention were smaller in schools serving higher proportions of students with low socioeconomic status and for students who had higher baseline levels of externalizing behavior. The discussion ...
Asymptotic Drying of Gelatin in Photographic Film

Abstract In this paper we study the asymptotic behavior of the solution for the diffusion equation ∂ u /∂ t = ∂[exp(−1/ u )∂( u /(1 + u ))/∂ x ]/∂ x with mixed nonlinear boundary conditions. The problem arises in the study of the diffusion of water in the gelatin layer of photographic film. We show that there exists a unique positive solution which converges to 0 asymptotically.
Extracellular protease of Penicillium roqueforti. II. Characterization of a purified enzyme preparation

Abstract The extracellular protease (E.C. 3.4.4.99) of Penicillium roqueforti BP-13 was isolated from concentrated cell-free extract by fractionation on Sephadex. Molecular weights of 49,000 and 45,000 daltons were established from gel filtration and gel electrophoretic techniques. The protease exhibited an activation energy of 8,000 cal/mol for the hydrolysis of casein. Above 45C the enzyme was subject to irreversible, first order thermal inactivation. Neither serine protease inhibitor, oxalate, or calcium-(II) had significant effect on enzymatic activity. Modification of the carboxyl groups with diazoacetoglycine methyl ester decreased activity by 90% indicating aspartic or glutamic acid residues at the active site. Of 15 peptides and amino acid esters evaluated as substrates none were hydrolyzed detectably. Casein components, α s - and β -casein, were extensively hydrolyzed after 20h incubation with the enzyme. κ -casein appeared to be unaffected. The rapid release of trichloroacetic acid-soluble nitrogen from a 1% casein suspension indicated that the fungal protease was a nonspecific proteolytic enzyme. Milk clotting studies revealed that the enzyme was 14 times more proteolytic than calf rennet for identical clotting times. However, because of its general proteolytic characteristic, the fungal protease was not an acceptable substitute for calf rennet in small cheese-making trials.
Two Methods of Determining [3H]Dexamethasone Distribution in Rat Subcutaneous Tissue

Several recent reports suggest that controlled local release of dexamethasone may be useful for preventing inflammation around an implantable glucose sensor [1,2]. This decrease in inflammation is expected to increase glucose sensor function and lifetime. Local delivery of dexamethasone would permit high interstitial drug concentrations at the site of glucose sensor implantation without producing high systemic drug levels. Although dexamethasone is a commonly used anti-inflammatory agent, its local concentration, diffusion coefficient and rate of elimination have not been reported following subcutaneous release. The ability of dexamethasone to penetrate subcutaneous tissue can be measured and quantified by comparison to mathematical models [3]. This method allows a reliable estimate of the drug concentration in the tissue near the implanted glucose sensor.Copyright © 2007 by ASME
The Relationship Between Objective Measures and Listeners’ Judgments of the Communicative Informativeness of the Connected Discourse of Adults With Aphasia

In this study, the connected discourse of 25 adults with aphasia was rated on the dimension of “informativeness” by 11 unfamiliar listeners using a direct magnitude estimation (DME) procedure. Thes...
Thermodynamic Aspects of Dicarboxylate Recognition by Simple Artificial Receptors

Recognition of dicarboxylates by bis-functional hydrogen-bonding receptors displays divergent thermodynamics in different solvent systems. NMR titration and isothermal titration calorimetry indicated that neutral bis-urea and bis-thiourea receptors form exothermic complexes with dicarboxylates in DMSO, with a near zero entropic contribution to binding. The increased binding strength of bis-guanidinium receptors precluded quantitative measurement of binding constants in DMSO, but titration calorimetry offered a qualitative picture of the association. Formation of these 1:1 complexes was also exothermic, but additional endothermic events occurred at both lower and higher host-guest ratios. These events indicated multiple binding equilibria but did not always occur at a discrete 2:1 or 1:2 host-guest molar ratio, suggesting higher aggregates. With increasing amounts of methanol as solvent, bis-guanidinium receptors form more endothermic complexes with dicarboxylates, with a favorable entropy of association. This switch from association driven by enthalpy to one driven by entropy may reflect a change from complexation involving the formation of hydrogen bonds to that promoted by solvent liberation from binding sites.
Establishing comprehensive, quantitative criteria for detection of restenosis and remodeling after percutaneous transluminal coronary angioplasty

To establish comprehensive criteria for detecting restenosis and remodeling, inter- and intraobserver reproducibility of quantitative arteriography in the analysis of 20 lesions immediately after and 6 months after percutaneous transluminal coronary angioplasty (PTCA) were assessed. Geometric single-plane (minimum, maximum, mean diameter and percent diameter stenosis), biplane (absolute and relative cross-sectional area stenosis), relative densitometric area stenosis and the average of densitometric area stenosis in orthogonal views were compared. A high intra- and interobserver reproducibility of all absolute measurements was found, with the highest correlations for minimum diameter and cross-sectional area (interobserver, r = 0.85 and 0.85; intraobserver, r = 0.93, and 0.95 for minimum diameter and cross-sectional area, respectively). Of the relative measurements, biplane geometric percent cross-sectional area stenosis was the most reliable and percent densitometric area stenosis was the most variable (interobserver, r = 0.67; intraobserver, r = 0.71). Only small differences were demonstrated for the absolute measurements between the analysis of lesions immediately after PTCA and after follow-up, whereas a greater variability was found for relative measurements, especially videodensitometry. In both circumstances, a poor correlation between relative densitometric cross-sectional area from orthogonal views was found, whereas geometric elliptical cross-sectional area correlated quite well with the average of densitometric percent cross-sectional area in orthogonal views (interobserver, r = 0.86; intraobserver, r = 0.84). Thus, data in this study support the suitability of geometric quantitative analysis for the assessment of PTCA results. Densitometry was the least reliable quantitative parameter.
Defective ATM-p53–mediated apoptotic pathway in multiple sclerosis

Defective elimination of autoreactive cells is thought to play a role in the development of autoimmune diseases including multiple sclerosis (MS). We examined the activation of the ATM-CHK2-p53 pathway in MS patients after subjecting their peripheral blood mononuclear cells to γ-irradiation. We found that peripheral blood mononuclear cells from a subset of MS patients show resistance to cell death induced by irradiation. This defect is due to impaired constitutive expression and activation of ATM (ataxia telangiectasia mutated), resulting in impaired stabilization of p53. We predict that these fundamental defects likely alter the regulation of the immune population of cells in MS and may contribute to the development or progression of the disease. Ann Neurol 2005;58:577–584
A beam-bunching system for a tandem electrostatic accelerator using solid state circuitry☆

Abstract A solid state buncher chopper system for a tandem electrostatic accelerator is described. Ten percent of the normal H 2 + beam from an exchange ion source is bunched to packets 6 ns fwhm on a target. The system was inexpensive to construct and is stable in operation.
Permeation studies of CFC alternative blowing agents for rigid polyurethane foams

In order to evaluate the migration characteristics of insulating gases and vapors, a method was developed to study the permeation characteristics of the blowing agents through films made from the same materials used to make foams. This paper describes a method for measuring the permeation characteristics through films that represent the foam polymer and summarizes data on the permeation characteristics for two polyisocyanurate polymers. These films are made by using commercial formulations without blowing agents. The blowing agents evaluated were: HCFC-22, HCFC-123, HCFC-141b, HFC-134a, HFC-152a, nitrogen (as an air model), and CFC-11 as a control
Deformation near the Casa Diablo geothermal well field and related processes Long Valley caldera, Eastern California, 1993–2000

Abstract Regional first-order leveling lines, which extend from Lee Vining, CA, to Tom’s Place, CA, have been surveyed periodically since 1957 by the U.S. Geological Survey (USGS), the National Geodetic Survey (NGS), and Caltrans. Two of the regional survey lines, or leveling networks, intersect at the Casa Diablo geothermal well field. These leveling networks, referenced to a distant bench mark (C916) near Lee Vining, provide time-series vertical control data of land-surface deformation that began around 1980. These data are also useful for delineating localized subsidence at Casa Diablo related to reservoir pressure and temperature changes owing to geothermal development that began in 1985. A comparison of differences in bench-mark elevations for five time periods between 1983 and 1997 shows the development and expansion of a subsidence bowl at Casa Diablo. The subsidence coincides spatially with the geothermal well field and temporally with the increased production rates and the deepening of injection wells in 1991, which resulted in an increase in the rate of pressure decline. The subsidence, superimposed on a broad area of uplift, totaled about 310 mm by 1997. The USGS established orthogonal tilt arrays in 1983 to better monitor deformation across the caldera. One tilt array (DBR) was established near what would later become the Casa Diablo geothermal well field. This array responded to magmatic intrusions prior to geothermal development, tilting away from the well field. With the start of geothermal fluid extraction in 1985, tilt at the DBR array reversed direction and began tilting into the well field. In 1991, geothermal power production was increased by a factor of four, and reservoir pressures began a period of steep decline. These changes caused a temporary three-fold increase in the tilt rate. The tilt rate became stable in 1993 and was about 40% lower than that measured in 1991–1992, but still greater than the rates measured during 1985–1990. Data from the local leveling networks spanning the well field and the bounding graben were analyzed for several 2-year periods (1993–1995, 1995–1997, and 1997–1999). Annual rates of change across the normal faults bounding the graben have steadily decreased for each 2-year period between 1993 and 1999, reflecting the slowing decline in geothermal reservoir pressure. Horizontal control data from a two-color electronic distance meter (EDM) defined the lateral extent of subsidence at Casa Diablo. The EDM and leveling data elucidate the localized effect of the shallow source of subsidence and the broader effect of the deeper magmatic inflation source. Data from bench marks common to both the vertical and the horizontal control networks were used to assess the effect of subsidence on the EDM base station (CASA). Modeling of geodetic data collected during periods of little or no magmatic inflation indicated that the CASA two-color EDM station is being drawn toward the well field at a rate of 3–5 mm/yr.
Detection of heteroquality taste mixtures

Detection thresholds were measured for sweet (sucrose), salty (sodium chloride), sour (citric acid), and bitter (quinine hydrochloride) and for the 11 possible mixtures of these four substances. These 11 mixtures (6 binary, 4 ternary, and 1 quaternary) all turned out to be stimulus additive, in the sense that a person could reliably detect mixtures whose individual components are weaker than their unmixed thresholds. Tastants too weak to be perceived alone can thus make impact when in mixtures. The threshold concentration for a given compound was reduced in approximate proportion to the number of compounds added to it. This liberal heteroquality additivity contests the widespread belief that heteroquality mixtures (different chemicals evoking different qualities) are nonadditive and homoquality mixtures (different chemicals evoking the same quality) are additive. Heteroquality additivity emerges on appropriate definition of the subject’s task by forced choice (unavailable to earlier investigators), in order to skirt methodological pitfalls. Operating together, homoand heteroquality additivity may concomitantly enable a person to sense natural mixtures of hosts of weak constituents, such as drinking water. In this regard, gustatory mixtures may function much as do mixtures of frequencies in audition and mixtures of gaseous compounds in olfaction.
Monotonicity, stability and egalitarianism

Abstract A division problem is a subset of the utility space representing the alternatives available to a group of agents. A solution is a method of selecting from each division problem in some class an equitable compromise. The egalitarian solution selects the only undominated alternative with equal coordinates. This solution is the only one to satisfy the following axioms: weak Pareto- optimality, symmetry, continuity, monotonicity (if the number of agents increases but not the resources at their disposal, all the original agents should help support the newcomers) and weak stability (the compromise should appear equitable to every subgroup).
Hydrostatic Pressure Enhances Chondrogenic Differentiation of Human Bone Marrow Stromal Cells in Osteochondrogenic Medium

This study demonstrated the chondrogenic effect of hydrostatic pressure on human bone marrow stromal cells (MSCs) cultured in a mixed medium containing osteogenic and chondrogenic factors. MSCs seeded in type I collagen sponges were exposed to 1 MPa of intermittent hydrostatic pressure at a frequency of 1 Hz for 4 h per day for 10 days, or remained in identical culture conditions but without exposure to pressure. Afterwards, we compared the proteoglycan content of loaded and control cell/scaffold constructs with Alcian blue staining. We also used real-time PCR to evaluate the change in mRNA expression of selected genes associated with chondrogenic and osteogenic differentiation (aggrecan, type I collagen, type II collagen, Runx2 (Cbfa-1), Sox9, and TGF-β1). With the hydrostatic pressure loading regime, proteoglycan staining increased markedly. Correspondingly, the mRNA expression of chondrogenic genes such as aggrecan, type II collagen, and Sox9 increased significantly. We also saw a significant increase in the mRNA expression of type I collagen, but no change in the expression of Runx2 or TGF-β1 mRNA. This study demonstrated that hydrostatic pressure enhanced differentiation of MSCs in the presence of multipotent differentiation factors in vitro, and suggests the critical role that this loading regime may play during cartilage development and regeneration in vivo.
Magnetic Field Enhancement of Dielectronic Recombination from a Continuum of Finite Bandwidth

We have examined dielectronic recombination of ${\mathrm{Ba}}^{+}$ and ${e}^{\ensuremath{-}}$ from a continuum of finite bandwidth. Applying magnetic fields of up to 240 G perpendicular to small electric fields from 0.1 to 5 V/cm increases the recombination rate, while applying the magnetic field parallel to the electric field does not change the rate. The largest magnetic field enhancement observed was approximately $50%$.
Personal air samplers for measuring occupational exposures to biological hazards.

Microbiological air samplers, designed to be worn as personal samplers, were evaluated for studying occupational exposures to aerosols of infectious and allergenic materials. Gelatin filter media, an impinger sampler, and spiral and cascade impactors were tested for collection efficiency for small (≤2 µm) latex spheres and for recovery of bacterial aerosols. Only 20% of an aerosol of 0.8 µm latex particles passed through the impinger uncollected, while recovery of bacteria equalled or exceeded collection in an all-glass impinger. Gelatin filters matched the collection efficiency of membrane filters, but were unsatisfactory for the isolation of bacteria sensitive to dehydration. The spiral sampler and the cascade impactor provide information on the size distribution of collected particles, although, at present, collection efficiencies for very small particles are too low for rigorously quantitative studies. Methods of collection, and sampling strategies for biological aerosols are similar to those used for...
Supplementary test procedures for overall treatment effect

Two tests are proposed for the nullity of the overall mean parameter. Simulation results are used to compare the empirical type I error rates of the tests and two other well-known tests from the literature. An example is given to demonstrate the application of the procedures.
Recursive stochastic deconvolution in the estimation of earthquake source parameters: synthetic waveforms

Abstract In this paper, a method of the linear minimum mean-squares error (LMMSE) solution for source inversion is presented in terms of a recursive algorithm. A covariance matrix of estimation error, as well as a resolution matrix are also computed through recursion. It is shown that this recursive solution corresponds to a stationary Kalman filtering estimation for a linear dynamic system, which makes it possible to perform satisfactorily in an environment where complete knowledge of the relevant signal characteristics is not available. In a stationary environment, our recursive solution converges to the optimum Wiener solution. In a rather straightforward manner, the multichannel deconvolution problem is translated into a set of recursive expressions. The procedures have been tested using a number of synthetic data sets, including a point and a complex source, with satisfactory results. It is found that the solution is improved recursively with each addition of new data. We have found further that it is the error-covariance matrix, not the resolution matrix, that gives a measurement of the recursive performance. Since the recursive scheme of LMMSE runs in a manner based on either block-by-block or sample-by-sample operation, the memory requirement can be quite small. For problems involving sparse matrices, the recursive algorithm leads to fast and efficient computation. This method is tested by examining the Sierra Madre earthquake (Ms = 5.8) of 28 June 1991, California. This event is well-recorded by the broad-band TERRAscope array. The moment tensor inversion through the presented method indicates that the solution is improved recursively when new data become available. It was found that the later arrivals on the observed seismograms have very little influence on the solution while the inclusion of new data from different stations yields substantial improvement on the mechanism to a certain point where further addition of data will not make much difference to the resulting best double-couple decomposition. However, the content of double-couple components shows a striking increase from ∼50 to ∼90% with the inclusion of more data from other stations. This result demonstrates clearly the robustness of our approach since the inadequacy of the source representation and the earth model in the moment-tensor inversion may be remedied by the inclusion of more data.
Newer agents against methicillin and/or gentamicin-resistant and -susceptible staphylococci.

The in vitro activities of the newer agents Deptomycin, Difloxacin, A-56620 and Ciprofloxacin were compared with those of vancomycin, rifampin and gentamicin against methicillin-susceptible and -resistant Staphylococcus aureus and co-agulase-negative staphylococci. All isolates were susceptible to vancomycin, rifampin, deptomycin and the quinolones tested. Newer agents had activity superior to that of vancomycin, whereas the activity of the newer agents and rifampin was comparable. Gentamicin resistance was frequent, however, the resistant staphylococci were susceptible to other antibiotics tested.
Modification of survival after ultraviolet light exposure in a wild-type and a polA strain of Escherichia coli B/r by preirradiation treatment with chloramphenicol or rifampin.

Abstract The shoulder of the UV fluence-survival curve of exponentially growing Escherichia coli B/r WP2 trpE65 was expanded by chloramphenicol pretreatment and an exponential segment with intermediate slope appeared between the shoulder and the final exponential segment. These changes were dependent on DNA replication. The transitions with UV exposure to increased slopes were ascribed to UV inactivation of qualitatively different repair systems, each dependent upon the accumulation in each bacterium of multiple DNA-containing redundant repair components, which must be inactivated before the respective transitions to decreased resistance occur. Rifampin, which blocks DNA-dependent RNA polymerase function, limited drastically expansion of the shoulder and development of the intermediate exponential slope. Bacteria defective in DNA polymerase I ( polA ) showed only a slight expansion of the shoulder with pretreatment with chloramphenicol. Since certain bacterial plasmids require RNA primer format on for initiation of replication and are not maintained in a polA strain, it is proposed that the chloramphenicol-promoted increase in resistance depends on the formation of multiple numbers of specific resistance episomes (called repairons in view of their role in DNA repair).
Owing loyalty to one's employer

Neither employer expectations of loyalty, nor good treatment of employees by employers, nor employee appreciation of employers, nor the duty of nonmaleficence, nor the intention to be loyal, nor the duty not to act disloyally provide a basis for a moral or ethical duty of employee loyalty. However, in addition to the law, a pledge to be loyal can obligate one to be loyal. But if the specific content of such a pledge is unstated, the conduct required by the pledge may be indefinite. Moreover, the content and implications of loyalty are fluid, varying from context to context. Consequently, there is only a limited basis for the thesis that employees owe loyalty to their employers.
Origin of Enantioreversal in the Rhodium-Catalyzed Asymmetric Hydrogenation of Prochiral Enamides and the Effect of the α-Substituent

The enantioselectivity of prochiral enamide hydrogenation depends on the structure of the enamide, with particular sensitivity to the nature of the α-substituent. Recently, Burk has reported a spectacular example of structure sensitivity for [Rh(DuPHOS)]+-catalyzed enamide hydrogenations: although enamides containing either carboxyl or tert-butyl α-substituents hydrogenate to ≥99% enantiomeric excess, the sense of enantioselection for the two substrate classes is reversed. Why should the magnitude and sense of enantioselectivity depend so strongly on the enamide α-substituent? We report the application of QM/MM (ONIOM) computations to address this long-standing issue in asymmetric catalysis. Specifically, we demonstrate that computational methods reproduce the α-substituent effect in enamide hydrogenation catalysis and probe how the interaction of the enamide CC bond and the catalyst varies with the structure of the substrate. The picture that emerges emphasizes the complex confluence of both electronic ...
The Multitasking Preference Inventory: Toward an Improved Measure of Individual Differences in Polychronicity

This article describes the initial development of a new measure of individual polychronicity, a construct indicating a preference for multitasking as opposed to performing only one task at a time. Following a brief review of past definitional issues, a revised definition is offered and a new measure of polychronicity—the Multitasking Preference Inventory (MPI)—is created based on this definition. Three studies describe the creation, pilot testing, and psychometric refinement of an initial pool of items (Study 1); a convergent and discriminant validity analysis (Study 2); and initial findings with respect to the criterion-related validity of scores on the MPI (Study 3). Together, these findings provide preliminary evidence for the reliability of scores on the MPI and the validity of the MPI in predicting variables relevant to multitasking.
Innovative Concept for a Heavy-Load Aircraft Utilizing a Two-Dimensional Wing

Heavy-load aircraft of conventional wing-body-tail design have become very large. Excessive size of such aircraft may present problems in the manufacturing process. In addition, large wing spans may cause some difficulties in ground handling. Increasing lift loads on large span cantilever wings will also increase the strength of the wing tip vortex. The concept presented herein proposes a means for substantially increasing the lift load capability of an aircraft without increasing the overall length and span of the configuration. The concept has a rectangular wing with a relatively low span and a large chord to provide the area required for high lift. Large fuselages are attached at each wing tip to provide the volume required for heavy loading. The fuselages serve as endplates for the wing and should preclude tip flow so that two-dimensional flow might be established on the wing. Elimination of the wing tip flow should prevent the formation of a tip vortex and eliminate the tip vortex hazard to trailing aircraft. Exploratory wind tunnel tests of such an aircraft concept have been conducted. Lessons learned from these tests are discussed herein in an effort to determine the validity of the concept.
Composition of uranium oxide surface layers analyzed by μ-Raman Spectroscopy.

Oxide thickness and composition averaged over a few square millimeter has been measured with nm thickness resolution by diffuse reflectance fourier transform infrared (FTIR) spectroscopy. {mu}-Raman spectroscopy has been done on powders and bulk samples in the past, and can now be done on surfaces layers with {micro}m lateral and depth resolution using con-focal microscopy. Here we apply con-focal-microscopy-based {mu}-Raman spectroscopy to a freshly polished/lightly oxidized and to heavily oxidized uranium to determine its sensitivity. The spectra show that {mu}-Raman spectroscopy does detect oxide thickness and oxide composition with high sensitivity.
Studies on the α and β forms of isotactic polypropylene by crystallization in a temperature gradient

Samples of isotactic polypropylene (PP) were zone-solidified in temperature gradients up to 300°C/cm at growth rates down to 3 μm/min. Oriented α-type spherulites were obtained only by nucleation. While β nucleation is extremely rare, the β phase is easily initiated by growth transformations along the oriented α front. Since the β phase was found to grow considerably faster than the α phase, the α-to-β transformation points diverge across the sample, interrupting growth of the oriented α fibrils. This causes subsequent nucleation to yield teardrop-shaped α spherulites. Differential scanning calorimetry (DSC) studies of zone-solidified PP show the β-phase to be favored by slow growth rates, high temperature gradients, and large degrees of superheat in the melt—all of which tend to suppress nucleation. Differential thermograms of largely β-PP obtained at a heating rate of 1°C/min show the actual melting and recrystallization of the β spherulites into the α form.
Generation of a domain in cadmium sulfide by injected acoustic noise

Abstract Traveling high electric field domains in piezoelectric semiconductors may be generated by injecting and amplifying an acoustic signal. The site and time of domain formation has been influenced by applying acoustic noise of the proper polarization into the sample.
Stress-induced glucocorticoids as a neuroendocrine alarm signal of danger

A considerable number of studies demonstrate that acute and chronic stressors prime CNS innate immune responses to subsequent pro-inflammatory challenges and that glucocorticoids mediate, in part, stress-induced sensitization of pro-inflammatory immune responses. Here, we explore the notion that GCs produce a persisting sensitization of CNS innate immune effectors (e.g. microglia) so that they will generate a potentiated pro-inflammatory response after the GC rise has dissipated, thereby enhancing the sickness response to infection or injury and maximizing the animal’s ability to neutralize danger. The stress-induced GC response is conceptualized here as an neuroendocrine warning signal or alarmin to the innate immune system, which prepares or sensitizes the innate immune response to potential danger. Thus, a new understanding of the stress response and its function (priming CNS innate immune responses to infection or injury during a fight/flight emergency) would be suggested.
Complete affine hypersurfaces. Part I. The completeness of affine metrics

On etudie les proprietes des hypersurfaces invariantes sous le groupe des transformations affines unimodulaires
The Characteristics of Innovative, Medical Devices

It is not easy to design an innovative and successful product in any field of engineering. Medical device design is further complicated by strict regulations. Current engineering design methods provide help in designing a good product, but the designer lacks tools that help him or her create an innovative, commercially successful product. In this study, we analyzed 51 innovative, award-winning medical devices against their competition to identify what made those products stand out from the competition. The method was focused on finding engineering-level characteristics that made the products successful and whether the characteristics of success in the medical device industry are similar to those of other industries. We used a set of innovation categories that have been shown to apply to mechanical engineering products. The results show that the most innovative medical devices were innovative in at least three categories. Overall, a majority (greater than 60%) of the award-winning medical devices exhibited enhanced user interactions, with a similar percentage displaying enhanced environmental interactions and architectural changes, compared with only 20% of devices offering an additional function. We conclude that designers of innovative medical devices need better design methods that extend beyond the functionality of the products.
Laminar dispersion in capillaries: Part III. Experiments in horizontal tubes including observations on natural convection effects

Experimental data on the axial dispersion of a solute in laminar flow in capillaries are presented for a range of Peclet numbers from 12 to 50,000 and of dimensionless time from 0.01 to 60. They show good agreement with the mathematical solutions over all ranges of variables as long as natural convection is unimportant. For slow flows it was observed that natural convection can both enhance and depress the dispersion significantly and that extremely small density differences (Δ p/p = 10−4) are adequate to cause these phenomena. A qualitative explanation for the apparently anomalous effects of natural convection is proposed.
Evolutionary biology: A kingdom revised

An international consortium of researchers has produced an impressive new tree of life for the kingdom Fungi. The results are a testament to cooperation between systematists with different expertise.
Position-effect variegation and the new biology of heterochromatin

The phenomenon of position-effect variegation has long been used as evidence for the importance of chromosome position to gene expression in eukaryotes. Investigations published within the past few years demonstrate that position-effect variegation is caused by multiple mechanisms, and that direct tests of hypotheses are possible with numerous model systems.
Determinants of disease phenotype in trypanosomatid parasites

Trypanosomatid parasites infect over 21 million people worldwide, with a range of disease phenotypes. Trypanosoma cruzi causes American trypanosomiasis, wherein 30-40% of infected individuals develop disease manifestations, most commonly cardiomyopathy but also digestive megasyndromes. In the case of Trypanosoma brucei, the etiological agent of African trypanosomiasis, disease progression can be rapid or slow, with early or late central nervous system involvement. Finally, Leishmania species cause leishmaniasis, a disease that ranges from self-healing but scarring cutaneous lesions to fatal visceral leishmaniasis in which parasites disseminate to the liver, spleen, and bone marrow. This review highlights parasite factors involved in disease phenotype in all three trypanosomatid diseases, with a particular focus on recent advances using large-scale 'omics' techniques.
Polydiacetylenes with Long Wavelength Absorption

A series of 1,6-disubstituted-2,4-hexadiynes, where the substituents are para-substituted benzene rings that have either a dicyanovinyl or tricyanovinyl group as one substituent and have either an ...
"Masterpiece" copolymer sequences by targeted equilibrium-shifting

We describe an equilibrium model to determine whether a random population of dynamic copolymer sequences could be driven by molecular recognition to a subset of sequences that tightly bind a specific ligand. The model predicts that the population's mean binding constant can be shifted, but because of competitive binding, only to a limited degree (ca. 2 orders of magnitude larger than the original mean). True chemical evolution will require a mechanism for selection and amplification.
The ons and offs of inducible transgenic technology: A review

Classical transgenic and gene-targeted mouse mutants are powerful model systems in which to study the pathogenesis of neurodegenerative diseases. However, a number of issues of fundamental importance to neurodegenerative research cannot be addressed using classical techniques. These include identification of the earliest events in disease pathogenesis and a determination of whether a particular pathogenic protein produces a inexorable or a reversible disease process. Both of these issues have profound implications for the rational development of new therapies. To address these questions, genetic techniques that allow pathogenic proteins to be expressed or knocked out with temporal and regional specificity have been developed. We have reviewed these systems, highlighting the tetracycline-regulated system because of its demonstrated utility in mice and its reversibility. These regulatable systems are a new and powerful tool for the neurobiologist and allow one to address a new set of important questions in an in vivo setting.
Thermal barrier coating adherence to Hf-modified B2 NiAl bond coatings

Abstract The durability of thermal barrier coatings (TBCs) deposited on Hf-modified B2 NiAl bond coatings has been investigated under thermal cycling conditions. The rate of bond coat oxidation and rumpling during thermal cycling was characterized and the cycles to failure measured. The location of cycling-induced cracks in the TBC multilayer was influenced by the bond coat composition but variation in TBC lifetime was small, despite the different failure modes. Analysis of the cycle-dependent degradation phenomena demonstrate a trade-off between rumpling resistance and interfacial toughness as a function of bond coat composition.
Racial differences in treatment of early-stage prostate cancer.

OBJECTIVES To determine whether differences existed in prostate cancer treatment received by white and African American men at a health maintenance organization where access to medical care is theoretically equal for all members and, if so, to determine the reasons for these differences. METHODS We used information from the Kaiser Permanente Northwest Tumor Registry to identify all men diagnosed with local- or regional-stage prostate cancer between 1980 and 2000. We compared the likelihood of treatment with curative intent (TCI) between the two races, adjusting for age, tumor grade, stage, and the presence of comorbid conditions. We reviewed medical records of all 79 African American men and a sample of 158 white men (matched for age, stage, grade, and year of diagnosis) to determine the reasons that men did or did not receive TCI. RESULTS Seventy-one percent of African American men and 82% of white men were treated with curative intent (P = 0.01). African American men were not more likely than white men to refuse TCI when it was offered (10.6% versus 8.1%, respectively; P = 0.6). However, urologists offered TCI less often to African American men than to white men (85% versus 91%, respectively; P = 0.02), and this difference could not be explained by differences in age, tumor grade, stage, or presence of comorbid conditions. CONCLUSIONS African American men were less likely to receive TCI than white men. Because all of the men were insured, economic factors did not cause this difference. Furthermore, the cause did not seem to be differences in age, tumor grade, stage, or comorbid conditions.
Operative treatment of peripheral lymphedema: a systematic meta-analysis of the efficacy and safety of lymphovenous microsurgery and tissue transplantation.

Background The purpose of this study was to quantify the efficacy and safety of microsurgery for lymphedema through a systematic meta-analysis, which has not been described before. Methods A literature search was conducted to identify all articles involving microsurgical treatment of lymphedema. Studies meeting criteria for inclusion were rated on methodologic quality based on the American Society of Plastic Surgeons levels of evidence. Demographic information, cause of lymphedema, and surgical technique were recorded. Quantitative change in lymphedema and perioperative complications were noted. Results Twenty-seven studies were included, with 24 offering level IV evidence and three offering level III evidence. Lymphovenous shunt procedures were performed in 22 studies and lymph node transplantation was performed in five. Excess circumference was reduced by 48.8 ± 6.0 percent, and absolute circumference was reduced by 3.31 ± 0.73 cm. Studies reporting change in volume demonstrated reduction in excess volume by 56.6 ± 9.1 percent, and absolute volume was reduced by 23.6 ± 2.1 percent. The incidence of no improvement in lymphedema postoperatively was 11.8 percent, and 91.2 percent of patients reported subjective improvement. Approximately 64.8 percent of patients discontinued compression garments at follow-up. Complications included operative-site infection (4.7 percent), lymphorrhea (7.7 percent), reexploration for flap congestion (2.7 percent), and additional procedures (22.6 percent). Conclusions Operative interventions for peripheral lymphedema appear to provide consistent quantitative improvements postoperatively, with a relatively wide safety margin. Lymph node transplantation may provide better outcomes compared with lymphovenous shunt, but well-designed head-to-head comparisons are needed to evaluate this further. Clinical question/level of evidence Therapeutic, III.
Content Mismanagement Systems

Today's content management systems produce Web pages on the fly that look just like ones handcrafted by humans. However, many CMSs' URLs are extremely long and undiscipherable, so you might not be able to tell what's on that page by just looking at the URL. While those systems' designers seem to know little about how users will use that content, other CMSs are more user-friendly. This essay explores differing CMS requirements and goals.