cssi/SciSciGPT-SciSciNet huggingface dataset:
Job injury issues among Hispanic immigrant employees in hospitality operations

Purpose – The increasing number of Hispanic immigrant employee workers in the hospitality industry in the USA has led to some imperative issues and questions, such as how communication barriers and culture gaps influence work injuries. The purpose of this study is to examine factors that influence the extent to which immigrant employees report work injuries to their managers.Design/methodology/approach – Using survey methodology, 154 full‐time employees working at a hospitality operation were requested to participate (60 percent were Hispanic immigrant employees, 40 percent were US born). Participants were given a Spanish or English language survey that contained the measures of interests, as well as demographic questions, and a debriefing statement.Findings – The results showed that immigrant workers reported fewer injuries to their supervisors/managers than US‐born workers and the extent to which Hispanic immigrants speak English was related to the frequency of reporting work injuries. Immigrant climate...
Time-resolved RNA SHAPE chemistry: quantitative RNA structure analysis in one-second snapshots and at single-nucleotide resolution

RNA selective 2'-hydroxyl acylation analyzed by primer extension (SHAPE) chemistry exploits the discovery that conformationally dynamic nucleotides preferentially adopt configurations that facilitate reaction between the 2'-OH group and a hydroxyl-selective electrophile, such as benzoyl cyanide (BzCN), to form a 2'-O-adduct. BzCN is ideally suited for quantitative, time-resolved analysis of RNA folding and ribonucleoprotein (RNP) assembly mechanisms because this reagent both reacts with flexible RNA nucleotides and also undergoes auto-inactivating hydrolysis with a half-life of 0.25 s at 37 degrees C. RNA folding is initiated by addition of Mg(2+) or protein, or other change in solution conditions, and nucleotide resolution structural images are obtained by adding aliquots of the evolving reaction to BzCN and then 'waiting' for 1 second. Sites of the 2'-O-adduct formation are subsequently scored as stops to primer extension using reverse transcriptase. This time-resolved SHAPE protocol makes it possible to obtain 1-second structural snapshots in time-resolved kinetic studies for RNAs of arbitrary length and complexity in a straightforward and concise experiment.
The Design of a Message Switching System: An Application and Evaluation of Modula

Modula is a new programming language for implementing dedicated, parallel systems. Following a systematic design technique, this paper illustrates the use of Modula for the design of a message switching communication system. A message switching system poses a number of interesting. problems: a high degree of concurrent activity exists, a variety of I/O devices need to be controlled, messages can have multiple destinations, and messages can be preempted. The strengths and weaknesses of Modula with respect to these specific problems and its utility as a general purpose language are evaluated.
Influence of Jet-Grid Turbulence on Flat Plate Turbulent Boundary Layer Flow and Heat Transfer

The influence of high mainstream turbulence on turbulent boundary layer flow and heat transfer is experimentally investigated for length Reynolds numbers between 4 {times} 10{sup 4} and 1.5 {times} 10{sup 6}. The high mainstream turbulence is produced by a round tube grid with uniform jet injection. Injected air is blown in either an upwind or downwind direction at a controllable flow rate. A flat plate test section instrumented with foil thermocouples is located downstream from the jet grid. The turbulence intensity decay and length scale growth along the test plate, the mean velocity and temperature profiles across the boundary layer, and surface heat transfer distribution are measured. The results show that the grid with downwind injection produces a slightly higher turbulence intensity and a smaller length scale than the grid with upwind injection. A higher turbulence intensity and a smaller length scale further enhance the surface heat transfer coefficient. The jet-induced high turbulence does not alter the downstream velocity and temperature profiles in their logarithmic regions, but the wake regions are lower than the zero turbulence profiles. The Reynolds analogy factor, the augmented friction factor, and the augmented Stanton number are higher than those from existing correlations when the jetmore » grid turbulence intensity is greater than 6 percent.« less
Electrostatic effects on the stability of discoidal high-density lipoproteins.

High-density lipoproteins (HDL) remove cholesterol from peripheral tissues and thereby help to prevent atherosclerosis. Nascent HDL are discoidal complexes composed of a phospholipid bilayer surrou...
A comparative study of ZPR-6/7 with MCNP/5 and MC2-2/REBUS

Abstract This work models the INL ZPR-6/7 assembly employing two different approaches: a probabilistic approach using MCNP/5 and a deterministic one using MC 2 -2/REBUS. With MCNP/5, each drawer of the assembly is modeled in detail with regard to geometry and fuel loading. In the deterministic approach, the MC 2 -2 collapses cross-sections in energy and space into a 15 few group structure homogenized spatially over each drawer for the REBUS 3D model. Various reactivity coefficients and reaction rates at different locations inside the core were evaluated and compared for both approaches and contrasted to published experimental data and were found to be in good agreement.
The effect of osmotic and ion-osmotic stresses on the mortality of rainbow trout (Salmo gairdneri)

Abstract 1. 1. The possibility that costs of ionic and osmotic regulation are different in fish was assessed using mortality rates of rainbow trout exposed to an ionically active substance, sodium chloride and a non-electrolyte, mannitol, in the ambient water. 2. 2. A 24-hr LC 50 of 175 mOsm was calculated from data for fish exposed to sodium chloride concns of 400, 450, 500, 550, 600, 650 and 700 mOsm. 3. 3. Similarly, a 24-hr LC 50 of 767 mOsm was calculated from data for fish exposed to mannitol concns of 400, 500, 600 and 700 mOsm. 4. 4. The relatively higher LC 50 for fish exposed to increased ion and osmotic concns suggest the costs of ionic regulation may be significantly greater than those associated with osmotic regulation.
A new algorithm for image noise reduction using mathematical morphology

Morphological openings and closings are useful for the smoothing of gray-scale images. However, their use for image noise reduction is limited by their tendency to remove important, thin features from an image along with the noise. The paper presents a description and analysis of a new morphological image cleaning algorithm (MIC) that preserves thin features while removing noise. MIC is useful for gray-scale images corrupted by dense, low-amplitude, random, or patterned noise. Such noise is typical of scanned or still-video images. MIC differs from previous morphological noise filters in that it manipulates residual images-the differences between the original image and morphologically smoothed versions. It calculates residuals on a number of different scales via a morphological size distribution. It discards regions in the various residuals that it judges to contain noise. MIC creates a cleaned image by recombining the processed residual images with a smoothed version. The paper describes the MIC algorithm in detail, discusses the effects of parametric variations, presents the results of a noise analysis and shows a number of examples of its use, including the removal of scanner noise. It also demonstrates that MIC significantly improves the JPEG compression of a gray-scale image. >
Second-order conditioning of Pavlovian conditioned inhibition

Abstract Two experiments are reported which investigated the conditioning of inhibition to a neutral stimulus as a result of its repeated pairing with a previouslyconditioned inhibitor. Both experiments employed a conditioned suppression technique with rat subjects. Experiment 1 detected the second-order inhibition through the retarded acquisition of concurrently administered excitatory conditioning. Experiment 2 found similar retardation in the acquisition of excitatory fear conditioning following previous second-order conditioning of inhibition to the stimulus. Implications are discussed for theories of the nature of inhibition and for second-order conditioning as an assessment technique.
Blood lead levels among children of lead-exposed workers: A meta-analysis.

Background To further assess the utility of targeted blood lead screening for children from households with members having occupational lead exposures, we conducted a meta-analysis of all available reports of take-home lead exposures. Our objective was to estimate the blood lead levels among U.S. children (ages 1‐5) from households with leadexposed workers. Methods Reports considered for inclusion were cited in Medline, Toxline, Excerpta Medica, and Bio-Med plus all unpublished reports available at the National Institute for Occupational Safety and Health through 1994. The a priori criteria for inclusion of U.S. reports required their having data on: (1) venous blood lead levels for children, (2) children’s ages, (3) data for at least five children, (4) workers’ occupations, (5) workers’ blood lead levels, and (6) data collection methods. Results Based on a meta-analysis of 10 reports from 1987 through 1994, the children (na 139) of lead-exposed workers (na 222) had a geometric mean blood lead level of 9.3 mg/dL compared to a U.S. population geometric mean of 3.6mg/dL (Pa 0.0006). Also in this group, 52% of the children had blood lead levels (BLLs) 10mg/dL compared to 8.9% in the U.S. (Pa.0010), and 21% of the children had BLLs 20mg/dL compared to 1.1% in the U.S. (Pa.0258). Conclusions: We estimate, based on 1981‐83 survey data, that there are about 48,000 families with children under six living with household members occupationally exposed to lead. If the findings from this meta-analysis (admittedly limited by small numbers) are generalizable, about half of the young children in these families may have BLLs 10mg/ dL. Data were too sparse to determine if children of workers with elevated blood leads were at greater risk than children whose parents were only known to be lead exposed. Our findings support the position that children of lead-exposed workers should be targeted for blood lead screening. Am. J. Ind. Med. 36:475‐481, 1999. Published 1999 Wiley-Liss, Inc. y
Thiol–ene adhesives from clove oil derivatives

This paper reports the synthesis of catechol-functionalized thiol–ene polymer networks as photocurable adhesives, where the adhesive interactions are derived from 4-allylpyrocatechol – a monofunctional alkene readily obtained from natural products of Syzygium aromaticum flower buds (clove). The thiol–ene photopolymerization process enables rapid cure times, low energy input, and solvent-free processing. The resulting polymer networks show improved macroscopic adhesion to a variety of substrates – including glass, marble, aluminum, and steel – by varying the concentration of 4-allylpyrocatechol in the network. Additionally, the effects of the catechol moiety on polymerization kinetics, thermomechanical, and mechanical properties were determined by comparing the synthesized catechol moiety to a series of control monomers such as eugenol (one phenol group) and methyl eugenol (no phenol groups).
Activation Energy for Benzene Hydrogenation over Supported Nickel Catalysts

THE vapour phase hydrogenation of benzene has been widely studied, but considerable doubt still remains about the activity of various catalysts and the activation energy of this highly exothermic reaction.
Extension of SBL Algorithms for the Recovery of Block Sparse Signals With Intra-Block Correlation

We examine the recovery of block sparse signals and extend the recovery framework in two important directions; one by exploiting the signals' intra-block correlation and the other by generalizing the signals' block structure. We propose two families of algorithms based on the framework of block sparse Bayesian learning (BSBL). One family, directly derived from the BSBL framework, require knowledge of the block structure. Another family, derived from an expanded BSBL framework, are based on a weaker assumption on the block structure, and can be used when the block structure is completely unknown. Using these algorithms, we show that exploiting intra-block correlation is very helpful in improving recovery performance. These algorithms also shed light on how to modify existing algorithms or design new ones to exploit such correlation and improve performance.
The Effect of Technical and Reflective Preservice Instruction on Pedagogical Reasoning and Problem Solving.

The effects of instruction in classroom management that emphasized technical skills and princi ples were compared to the effects of instruction that emphasized reflective and constructive processes. Techniques and principles from research on teaching were emphasized in the technical condition. The reflective condition engaged preservice students in examining and extending their conceptions of classroom management. At posttesting, participants completed a problem-solving inventory and were interviewed using a video stimulated measure to assess their reasoning and problem solving in classroom management. Participants in the reflective condition provided more reasons for their decisions and expressed a greater sense of responsibility for motivating student learning and establishing a positive learning environment than did participants in the technical and control conditions. Compared to technical and control participants, participants in the reflective group used strategies more often to solve problems. Diff...
The Relationship of Macular Pigment Optical Density to Serum Lutein in Retinitis Pigmentosa

PURPOSE. To determine whether macular pigment optical density (MPOD) is related to serum lutein or serum zeaxanthin in patients with retinitis pigmentosa. METHODS. The authors measured MPOD with heterochromatic flicker photometry, serum lutein and serum zeaxanthin by high performance liquid chromatography, and central foveal retinal thickness by optical coherence tomography (OCT) in 176 patients (age range, 18‐68 years) with typical forms of retinitis pigmentosa; 37 (21%) of these patients had cystoid macular edema (CME) by OCT. The authors performed multiple regression analysis with MPOD as the dependent variable and with loge serum lutein and loge serum zeaxanthin as independent variables adjusting for age, sex, iris color, central foveal retinal thickness, and, in some analyses, serum total cholesterol. RESULTS. MPOD increased with increasing serum lutein (P 0.0017) and decreased with increasing serum total cholesterol (P 0.0025) but was unrelated to serum zeaxanthin. MPOD was higher in patients with brown irides than in patients with lighter irides (P 0.014) and was nonmonotonically related to central foveal retinal thickness (P 0.0001), being lower in eyes with more photoreceptor cell loss and in eyes with moderate to marked CME. CONCLUSIONS. MPOD is independently related to serum lutein, serum total cholesterol, iris color, and central foveal retinal thickness in patients with retinitis pigmentosa. (Invest Ophthalmol Vis Sci. 2010;51:1086‐1091) DOI:10.1167/iovs.09-3396
Fire or ice: anticorrelation of volcanism and glaciation in California over the past 800,000 years

Compilation of published ages of Quaternary volcanism in eastern California indicates that volcanism was episodic, with maxima occurring during interglacial periods. The smoothed age distribution shows peaks at 10, 100, 185, 320, and 690 kyr, corresponding to interglacial cycles 1, 5, 7, 9, and 17. This implies that volcanism was modulated by changes in climate, although the processes that link the two are not well understood. Several factors, including transient loads imposed across rugged topography by ice and water and changes in groundwater regime, may provide the link. Although climatic modulation of volcanism is generally tied to changes in sea level, these data indicate that even volcanoes far from the coast can be affected by climatic change.
The effect of adsorption on the effectiveness factor of catalyst pellets

Abstract This paper develops the effectiveness factors of catalysts for two reaction models and shows that this factor is dependent not only upon size, shape, effective diffusivity and surface reaction velocity constant, but also upon the reaction model, surface coverage by adsorption, degree of conversion and surface concentration. Because of the complex and uncertain nature of the effectiveness factor of porous catalyst pellets it is important in kinetic studies to use small pellets having an effectiveness factor of nearly unity so that the reaction rate per unit mass is nearly independent of catalyst size.
Density dependence of the room temperature thermal conductivity of atomic layer deposition-grown amorphous alumina (Al2O3)

We report on the thermal conductivity of atomic layer deposition-grown amorphous alumina thin films as a function of atomic density. Using time domain thermoreflectance, we measure the thermal conductivity of the thin alumina films at room temperature. The thermal conductivities vary ∼35% for a nearly 15% change in atomic density and are substrate independent. No density dependence of the longitudinal sound speeds is observed with picosecond acoustics. The density dependence of the thermal conductivity agrees well with a minimum limit to thermal conductivity model that is modified with a differential effective-medium approximation.
Factors associated with the all-terrain vehicle mortality rate in the United States: An analysis of state-level data

The purpose of this article is to determine and quantify the factors associated with the all-terrain vehicle (ATV) mortality rate in the United States, based on an analysis of state-level data. From 1990 through 1999, there were about 2400 reported deaths in the U.S. involving ATVs. The population-based mortality rate during this time period amounted to about 0.84 deaths per million persons per year, but varied considerably among the 50 states-ranging from a low of 0.09 deaths per million person-years in Rhode Island to a high of 6.33 deaths per million person-years in West Virginia. This variation provides an opportunity for quantifying some of the key factors associated with the ATV mortality risk. The analysis was conducted in a two-stage regression process, with the state mortality rates estimated in the second stage with a negative binomial regression model. The results indicate that the ATV mortality rate was systematically related to ATV usage rates (a measure of risk exposure) and a number of the characteristics of the potential rider pool. These included: the proportion of the state populations that was male, young, lived in rural areas, was college educated, and non-Hispanic white.
Molten metal burn of the foot: a preventable injury

Molten metal burns of the feet remain a common injury to foundry workers. A case is reported of a foundry worker who sustained circumferential molten metal burns of the distal foot and toes necessitating amputation of four toes. This severe injury could easily have been prevented by the use of protective footwear and spats.
Antitumor action of several new piperazine derivatives compared to certain standard anticancer agents.

Summary The single intraperitoneal acute LD 50 doses of the following piperazine derivatives for Sprague-Dawley rats were as follows: bulk lot crystals A 8103, 200 to 225 mg./kg., and A 20065, 375 mg./kg.; for powdered processed vial packaged A 8103, 75 mg./kg., and A 20968 150 mg./kg. The single intraperitoneal acute LD 50 of the latter two drugs in Swiss mice was as follows: A 8103, 225 mg./kg., and A 20968, 400 mg./kg. A 8103 and A 20065 were more effective at comparable doses in preventing Walker 256 tumor takes in rats and in depressing established tumor growth than were nitrogen mustard or 5-FU. These two piperazine agents were equally effective in preventing tumor takes when administered orally or by the intraperitoneal routes. The time of first appearance of Walker 256 tumor in rats was delayed more than twice as long in animals treated with A 8103, compared with groups treated with the selected standard antineoplastic agents. A 8103 was effective in reducing subcutaneous tumor takes in rats in doses as low as 0.1 LD 50 , in contrast to HN 2 and 5-FU, both inactive in 0.4 LD 50 . A 8103 prepared in vials (LD 50 75 mg./kg.) had greater antineoplastic activity against Walker 256 tumor in the rat than did A 20968, but the latter was more effective against sarcoma 180 in the mouse than A 8103 in comparable doses. Intraperitoneal LD 50 value for A 8103 was 35 mg./kg. in dogs. Leukopenia and agranulocytosis were the chief signs of laboratory toxicity due to A 8103. Autopsy revealed pulmonary consolidation and hemorrhage, aplasia of myelocytic elements of the bone marrow, renal tubular necrosis and hepatic lobular necrosis. Of the three piperazine derivatives studied, bromopropionyl piperazine (A 8103) appeared to be most effective and superior to HN 2 or 5-FU against Walker 256 tumor in the rat.
Cholesterol Particle Growth and Dissolution Rates II:Retardation Effects of Cholate

The influence of cholate on the precipitation behavior of cholesterol in aqueous media has been investigated as a function of pH. The Coulter counter was employed to follow the particle size distribution changes with time in the supersaturated and undersaturated cholesterol suspension systems. It was found that in the high pH region ( p H > ˜ 6.5 ) the rates of growth and dissolution of the unstable phase and the rates of growth and dissolution of the stable phase were markedly retarded. At pH 8 and higher, the processes appeared to become completely inhibited. These observations are consistent with the mechanism involving the interfacial interaction of the cholate ion with the cholesterol crystal surface resulting in the formation of a barrier for interfacial transport of cholesterol from solution to solid. The data also suggest that at a low pH cholic acid catalyzes the deposition processes of cholesterol. The biological implications of these findings are pointed out.
An ELISA for selectins based on binding to a physiological ligand

Abstract Members of the selectin family of adhesion receptors, consisting of L-, P- and E-selectin, mediate the initial interaction between leukocytes and endothelium during leukocyte trafficking from the blood into tissue sites. These receptors have attracted great attention in recent years due to their participation in a number of acute and chronic inflammatory diseases. We describe here a new ELISA that measures the binding between selectin–IgG chimeras and a physiological ligand for L-selectin and can be used to screen selectin inhibitors. The ligand used is a mucin-like glycoprotein known as GlyCAM-1, which is derived from high endothelial venules in secondary lymphoid organs. We demonstrate binding of all three selectins to GlyCAM-1 and demonstrate that the binding interactions satisfy a number of important criteria. The advantage of this ELISA over previous assays is that a macromolecular physiological ligand is employed, rather than a fortuitous or simplified carbohydrate ligand. Thus, the protein–carbohydrate interactions, as well as other interactions contributing to ligand recognition, can be investigated. The assay is suitable for high-throughput screening of compounds and may find use in the identification of selectin antagonists with anti-inflammatory potential.
Mass spectrometric fragmentation of saturated six membered heterocyclic systems containing two chalcogen family atoms

The mass spectra of six-membered saturated heterocycles containing oxygen, sulphur, selenium and tellurium in the 1,4-positions have been measured. The differing fragmentation modes have been characterized using high resolution, low voltage and metastable ion scan techniques. The important decomposition reactions of the molecular ions involve elimination of C2H4 and CH2X (X is a chalcogen atom) and formation of [C2H4X]+ and C2H5+. The propensities of these reactions vary systematically as a function of the ability of the chalcogen to stabilize a positive charge.
Blood venting through the pneumostome in terrestrial slugs

Abstract 1. Terrestrial slugs eject blood through the pneumostome in response to injection into the hemocoel of acetylcholine, 5-hydroxytryptamine, dopamine, and histamine. 2. This blood-venting response can be initiated also by osmotic, electrical, and mechanical stimuli. 3. Normally the response terminates rapidly; it can be elicited repeatedly in a given individual. Full recovery occurs within a few days. 4. The mechanism resembles blood ejection through the hemal pore of Lymnea stagnalis . Possible physiological roles of the response in slugs are discussed.
Use of thin films for high-sensitivity angle measurement

We propose to use thin films to provide a drastic improvement of measurement sensitivity in the recently developed small-angle measurement method, namely, angle measurement based on the internal-reflection effect. By designing the thin films (single layer or multiple layers) so that they provide an antireflection effect in the vicinity of the critical angle, we show that the sensitivity of angle measurement can be increased exponentially with the increase of the number of thin-film layers. This method provides a new means of designing angle sensors with increased sensitivities without having to increase the number of reflections and therefore the physical size and the required fabrication accuracy of the reflection prisms. We describe the design of the thin films for this particular application and the analysis of measurement sensitivity and range as determined by the material and the number of layers of the thin films. Selection of the optimal initial angle for high linearity performance is also discussed.
Cross-protection experiments with parasitoids in the genus Microplitis (Hymenoptera: Braconidae) suggest a high level of specificity in their associated bracoviruses

The immunological and developmental effects of bracoviruses (BVs) from three parasitoids in the genus Microplitis (Braconidae: Microgastrinae) were compared in the hosts Pseudoplusia includens and Heliothis virescens (Lepidoptera: Noctuidae). Southern blotting experiments indicated that viral DNAs from Microplitis demolitor bracovirus (MdBV) cross-hybridized with viral DNAs from Microplitis croceipes bracovirus (McBV) and Microplitis mediator bracovirus (MmBV) under conditions of high stringency. Injection of calyx fluid plus venom from each parasitoid species dose-dependently delayed development of P. includens and H. virescens. Each virus also inhibited pupation of P. includens but not H. virescens. In situ hybridization experiments indicated that MdBV and McBV persistently infect hemocytes in both hosts while MmBV persistently infects hemocytes in P. includens but not H. virescens. While MdBV infection induced a loss of adhesion by most plasmatocytes, McBV and MmBV infection induced a loss of adhesion in less than 50% of cells. Cross-protection experiments indicated that calyx fluid plus venom from one species usually protected progeny of another species from encapsulation but did not always promote successful development.
Controlling the Optical Properties of Plasmonic Disordered Nanohole Silver Films

Disordered nanohole arrays were formed in silver films by colloidal lithography techniques and characterized for their surface-plasmon activity. Careful control of the reagent concentration, deposi...
Investigation of the quartz resonator as an industrial cleaning monitor

The evaluation of cleaning processes can be performed in real time using the quartz resonator (QR) cleaning monitor as an in situ probe to monitor surface contamination. Viscous properties of thin films are modeled to determine the QR's limitation to film thickness in contact with liquids of varying properties. The demonstrated ability to provide submonolayer mass detection during a cleaning process allows this monitor to be used to probe the kinetics and effectiveness of a cleaning process. This capability can rapidly evaluate the total effectiveness of environmentally friendly alternative cleaning processes needed to replace cleaners such as chlorofluorocarbons (CFCs) and chlorinated hydrocarbons. These monitors could also be used to verify cleaning bath integrity so that bath cleaning solution changes are optimized. This condition would maintain high product quality and yield while minimizing waste from disposal.
Dedekind Finite Rings and a Theorem of Kaplansky

Abstract A ring Ris Dedekind Finite(=DF) if xy = 1 implies yx = 1 for all x, yin R. Obviously any subring of a DFring Ris DF. The object of the paper is to generalize, and give a radically new proof of a theorem of Kaplansky on group algebras that are Dedekind finite. We shall prove that all right subrings of right and left self-injective (in fact, continuous) rings are DF. Dedicated to Ahmad Shamsuddin (1991–2001), in memoriam.
Patterns of Epipelic Algal Abundance with Depth, Trophic Status, and Acidity in Poorly Buffered New Hampshire Lakes

The biovolume and species composition of algae on sediments in 20 poorly buffered New Hampshire lakes were surveyed in autumn to delineate patterns of community structure and composition with acidi...
THE KINETICS OF HETEROGENEOUS ISOTOPIC EXCHANGE

Summary Isotopic exchange of phosphate ions between soil and solution was examined with particular emphasis on the slower reaction involving the incorporation of the tracer in the solid phase that follows the very fast exchange reaction between the solution and the surface of solid. Experimental data fitted both an equation composed of a sum of exponentials and a much simpler two-constant equation. The goodness of fit was similar in each case but it was concluded that the exponential type of equation was not useful as a means of elucidating the mechanisms involved. The two-constant equation may be derived from the kinetics of crystallization and recrystallization processes, and therefore provides an interpretation which is amenable to experimental verification.
A lower bound on the partition function for a classical charge symmetric system

A lower bound is obtained for the grand canonical partition function (and hence for the pressure) of a charge symmetric system with positive definite interaction. For the Coulomb interaction the lower bound on the pressure is the Debye-Huckel approximation.
Measuring the force production of the hormogonia of Mastigocladus laminosus.

The cyanobacterium Mastigocladus laminosus forms hormogonia, which glide slowly away from the parent colony by extruding slime out of nozzles. Using video microscopy, we observed hormogonia embedded in and moving through 1–4% agar solutions with an average velocity of 0.5 μm/s. Agar is non-Newtonian and is subject to shear-thinning so that its viscosity greatly increases at low shear rates. We measured the viscosity of these agar solutions at the very low shear rates appropriate for gliding hormogonia and found it to vary from 1 to 52 million centipoise. Then, by applying a Newtonian drag coefficient for a 100-μm-long, cigar-shaped hormogonium, we found that it produced a force of several million pN. A typical hormogonium has 10–100 thousand 9-nm-wide slime extrusion nozzles. Wolgemuth et al. have proposed hydration-driven swelling of the polyelectrolyte slime ejected from these nozzles as the force production mechanism, and our experiment found a large nozzle force that was consistent with this hypothesis. Average single nozzle force depended on viscosity, being large when the viscosity was high: 71 pN in 3% and 126 pN in 4% agar.
Cloning, Antisense RNA Inhibition, and the Coordinated Expression of UDP-Glucose Pyrophosphorylase with Starch Biosynthetic Genes in Potato Tubers

Summary A UDP-glucose pyrophosphorylase (UDPG-PPase, E.C. 2.7.7.9) cDNA from potato ( Solanum tuberosum L.) tuber was cloned and sequenced. RNA analysis revealed expression in all tissues of the developing potato plant and that UDPG-PPase RNA could be induced by high sucrose treatments to exised leaves. In tubers, a coordinated expression of UDPG-PPase RNA with the RNA levels of several additional enzymes involved in the conversion of sucrose to starch was observed at harvest. Tubers of potato plants transformed with a patatin promoter-antisense-UDPG-PPase cDNA fusion were stored for 0, 1, 3 and 6 weeks at 4°C and 12°C. The tubers expressed various levels of antisense and sense UDPG-PPase RNA. The maximum antisense-mediated inhibition of UDPG-PPase enzyme activity was 30%, and this inhibition was maintained throughout the six weeks of storage at both 4°C and 12°C. No significant changes could consistently be found in Glc-1-P, Glc-6-P, Fru-6-P, UDP-Glc, glucose or fructose content in the transgenic tubers compared to wild type tubers. However, a statistically significant decrease in sucrose content was associated with the transgenic reduction of UDPG-PPase activity after 3 and 6weeks of storage.
Young Children's Opportunities to Use and Learn Theme-Related Vocabulary Through Buddy “Reading”

This qualitative study examined whether and how preschoolers' social interactions during buddy “reading” supported their use and learning of theme-related vocabulary. Data included 32 transcribed videos of 14 preschoolers engaged in buddy “reading.” Interaction analysis and constant comparative methods were applied to identify (1) patterns of social interactions that occurred, (2) patterns of opportunities for children to use and learn themed vocabulary, and (3) patterns that hindered such vocabulary opportunities. Findings included three patterns of social interactions: collaborative, tutor–tutee, and parallel. Each differentially affected opportunities for using and learning theme-related vocabulary. Opportunities to use and learn words occurred when children provided exposures to vocabulary words or clarified concept knowledge for their buddy. Opportunities were hindered when buddies struggled over participation, “reading” roles, or content.
Visualizing Banking and Financial Products: A Comparative Study of Chinese and American Practices:

This study examines the visual rhetoric used in Chinese and American promotional business communication. Comparing banking and financial product brochures published in the two countries, the study finds similar as well as different visual strategies. Most importantly, the Chinese samples frequently use visual metaphors, whereas the American samples hardly do. Prompted by this finding, I review relevant literature on visual metaphors and examine their structures and rhetorical functions. In addition, the study suggests that buyer images and cartoon images are used differently in the two countries, whereas product-related images are used similarly. I explore the contextual and cultural roots of these findings and offer suggestions on how to visually communicate with the Chinese audience and other international audiences.
Speckle propagation through atmospheric turbulence: effects of partial coherence of the target

Based on ABCD ray matrix theory and a random phase screen model for the target surface, analytic expressions are developed for the normalized mutual coherence function (MCF) of a reflected Gaussian-beam wave from a finite target in the presence of atmospheric turbulence. This analysis features both pupil plane and image plane expressions and includes partial and fully developed speckle from the target. The target model is a combination of a thin random phase screen and limiting aperture stop such that a weak screen corresponds to a mildly-rough target and a strong (or deep) random phase screen corresponds to fully developed speckle. From the normalized MCF, estimates are given for the speckle size in the pupil plane and image plane as a function of transmitted beam wave characteristics, size and roughness of the target, and size of the receiver collecting lens.
Family Care Responsibilities and Employment: Exploring the Impact of Type of Family Care on Work–Family and Family–Work Conflict

This study compared work–family and family–work conflict for employed family caregivers with disability-related care responsibilities in contrast to employed family caregivers with typical care responsibilities. Using data from the 2002 National Study of the Changing Workforce, a population-based survey of the U.S. workforce, formal and informal workplace supports of employees with disability-related family care were compared with those of employees with typical family care responsibilities. Results reveal that family caregivers with disability-related family care responsibilities face higher levels of both types of conflict, have lower incomes, and receive fewer informal supports compared with family caregivers with typical care responsibilities. In future studies of a diverse workforce, exceptional care responsibilities need to be conceptualized differently than typical care. Efforts are also needed to address the supports within the workplace and community that do assist family caregivers with exceptio...
A Mathematical Images Group Model to Estimate the Sound Level in a Close-Fitting Enclosure

This paper describes a special mathematical images model to determine the sound level inside a close-fitting sound enclosure. Such an enclosure is defined as the internal air volume defined by a machine vibration noise source at one wall and a parallel reflecting wall located very close to it and acts as the outside radiating wall of the enclosure. Four smaller surfaces define a parallelepiped for the volume. The main reverberation group is between the two large parallel planes. Viewed as a discrete line-type source, the main group is extended as additional discrete line-type source image groups due to reflections from the four smaller surfaces. The images group approach provides a convergent solution for the case where hard reflective surfaces are modeled with absorption coefficients equal to zero. Numerical examples are used to calculate the sound pressure level incident on the outside wall and the effect of adding high absorption to the front wall. This is compared to the result from the general large room diffuse reverberant field enclosure formula for several hard wall absorption coefficients and distances between machine and front wall. The images group method is shown to have low sensitivity to hard wall absorption coefficient value and presents a method where zero sound absorption for hard surfaces can be used rather than an initial hard surface sound absorption estimate or measurement to predict the internal sound levels the effect of adding absorption.
Generation of Free Oxygen Radicals and the Toxicity of Hemoglobin Solutions

The observed toxicity of hemoglobin solutions (HbS) might depend, at least in part, on the tendency of Hb to autoxidation with generation of oxygen free-radicals. Aims of this study were: (1) to quantitate plasma elevations of H2O2 and lipid peroxides after replacement of 1/3 of calculated blood volume in various groups of rabbits with different Hb solutions; (2) to correlate these elevations with parameters of brain, heart, lung, liver and kidney injury or dysfunction; and (3) investigate the protective effect of mannitol as a radical scavenger. One Hb solution contaminated with stromal phospholipids raised H2O2 from 31.2 ± 1.9 to 166 ± 20 μmol/ml, lipid peroxides from 1.62 ± 0.5 to 7.29 ± 0.3 nmol/ml, CK-BB (brain isoenzyme) from 250 ± 25 to 470 ± 50 IU/L, CK-MB (myocardial isoenzyme) from 2.98 ± 0.03 to 10.73 ± 1.3 IU/L and SGPT from 38.1 ± 5 to 167 ± 45 IU/L, and reduced PaO2 from 87 ± 10 to 57.5 ± 2.5 mm Hg and creatinine clearance from 1.5 ± 0.3 to 0.13 ± 0.03 mg/min/Kg. These changes were progressi...
Conservation of receptive-field properties of superior colliculus cells after developmental rearrangements of retinal input.

The formation of topographic maps requires not only that afferents synapse with the appropriate targets, but that the spatial relationships between the afferents be maintained. During development, in addition to the formation of the topographic map, the connectivity patterns responsible for the receptive-field properties of the target cells are being formed. The extent of interaction between these two processes is unknown. The present study addresses this question by manipulating afferent/target ratios during development, thus altering the topography of the map, and studying the effects of this alteration on the receptive-field properties of single target cells in the adult.Partial unilateral lesions of the superior colliculus (SC) were made in neonatal hamsters. These lesions result in a compression of the retinotopic map onto the remaining collicular fragment. Single cells were recorded from the superficial gray layer of the SC in the adult in response to visual stimuli. Receptive-field properties observed in lesioned animals were compared to those in normal animals and in sham operates.Receptive-field properties were largely unaffected by the change in the topographic map. There was no difference in the receptive-field size of single tectal cells of lesioned and unlesioned animals. Stimulus velocity and stimulus size tuning functions remained the same. This raises the possibility that, rather than the expected increase in convergence of retinal ganglion cells (RGC) onto single collicular cells, single SC cells receive input from ganglion cells representing the same amount of retinal area as in unlesioned animals. The excess ganglion cells created by the partial target removal would then project elsewhere and/or reduce their arbor within the SC. Regardless of the mechanism, it is clear from our results that circuitry in the retinotectal system of the hamster can compensate for conditions of increased afferent availability and thus maintain receptive-field properties.
Reef fishes use sea anemones as visual cues for cleaning interactions with shrimp

Marine cleaners benefit diverse fish clients via removal of ectoparasites, yet little is known about how fishes locate small, inconspicuous cleaner shrimps on coral reefs. Pederson shrimp Ancylomenes pedersoni are effective cleaners in the Caribbean Sea, and additionally form obligate associations with corkscrew sea anemones Bartholomea annulata, which also serve as hosts to a variety of other crustacean symbionts. We examined the visual role of B. annulata to reef fishes during cleaning interactions with A. pedersoni by comparing anemone characteristics with fish visitation rates, and by manipulating the visibility of anemones and cleaner shrimp in field experiments using mesh covers. Rates of visitation by fishes to cleaning stations increased primarily with anemone body size and the total number of crustacean symbionts, but did not change consistently in response to covers. Fishes posed for cleaning at stations only where anemones remained visible, regardless of whether shrimp were visible. Shrimp at stations where anemones were covered performed fewer cleaning interactions with fishes, as fishes did not continue to pose when anemones were not visible. We conclude that anemones serve as visual cues to client fishes prior to cleaning by shrimp. These visual cues facilitate fish cleaning interactions with shrimp, and provide a previously unknown symbiotic benefit to cleaner shrimp from association with sea anemones.
Compositional softening in Mg-Al spinel

Deviations from stoichiometry in Mg-Al spinel (MgO - nAl2O3, n > 1) cause a marked decrease in both the high-temperature critical resolved shear stress (CRSS) and the steady-state flow stress for b...
Bayesian Feature Selection for High Dimensional Linear Regression via the Ising Approximation with Applications to Genomics

MOTIVATION Feature selection, identifying a subset of variables that are relevant for predicting a response, is an important and challenging component of many methods in statistics and machine learning. Feature selection is especially difficult and computationally intensive when the number of variables approaches or exceeds the number of samples, as is often the case for many genomic datasets. RESULTS Here, we introduce a new approach--the Bayesian Ising Approximation (BIA)-to rapidly calculate posterior probabilities for feature relevance in L2 penalized linear regression. In the regime where the regression problem is strongly regularized by the prior, we show that computing the marginal posterior probabilities for features is equivalent to computing the magnetizations of an Ising model with weak couplings. Using a mean field approximation, we show it is possible to rapidly compute the feature selection path described by the posterior probabilities as a function of the L2 penalty. We present simulations and analytical results illustrating the accuracy of the BIA on some simple regression problems. Finally, we demonstrate the applicability of the BIA to high-dimensional regression by analyzing a gene expression dataset with nearly 30 000 features. These results also highlight the impact of correlations between features on Bayesian feature selection. AVAILABILITY AND IMPLEMENTATION An implementation of the BIA in C++, along with data for reproducing our gene expression analyses, are freely available at http://physics.bu.edu/∼pankajm/BIACode.
Modeling Equity Compensation with Accounting Contingencies

Of late, both U.S. and International firms have increased the granting of performance-contingent equity awards to their executive officers. Beyond simple stock options, these awards frequently include accounting-based performance targets. Failure to meet or exceed these targets causes award forfeiture. While now a common component in executive pay, little is known about how to value these instruments. In this paper, we model the expected payoff from an equity award with accounting-based payout conditions. The model incorporates numerous characteristics of awards seen in practice, including the coupling of stock price and accounting targets, multiple accounting targets, sliding payout schedules, and the adoption of both “and” and “or” conditions that trigger payout. We also translate the expected payoff into an approximate present value. Given the growing prevalence of performance-contingent features in executive pay, this exercise is important to academics, board members and shareholders, along with other market participants and regulators.
Diagnosis of heterotaxy syndrome by fetal echocardiography

We report a series of 13 consecutive patients diagnosed in utero with heterotaxy syndrome in which we found a slight predominance (8 of 13) of fetuses with right atrial isomerism. In previous studies in which diagnosis of left or right isomerism was made based upon findings at fetal echocardiography, there has been a preponderance of infants (95%) diagnosed with left isomerism.
The unseen iceberg: plant roots in arctic tundra

Plant roots play a critical role in ecosystem function in arctic tundra, but root dynamics in these ecosystems are poorly understood. To address this knowledge gap, we synthesized available literature on tundra roots, including their distribution, dynamics and contribution to ecosystem carbon and nutrient fluxes, and highlighted key aspects of their representation in terrestrial biosphere models. Across all tundra ecosystems, belowground plant biomass exceeded aboveground biomass, with the exception of polar desert tundra. Roots were shallowly distributed in the thin layer of soil that thaws annually, and were often found in surface organic soil horizons. Root traits - including distribution, chemistry, anatomy and resource partitioning - play an important role in controlling plant species competition, and therefore ecosystem carbon and nutrient fluxes, under changing climatic conditions, but have only been quantified for a small fraction of tundra plants. Further, the annual production and mortality of fine roots are key components of ecosystem processes in tundra, but extant data are sparse. Tundra root traits and dynamics should be the focus of future research efforts. Better representation of the dynamics and characteristics of tundra roots will improve the utility of models for the evaluation of the responses of tundra ecosystems to changing environmental conditions.