cssi/SciSciGPT-SciSciNet huggingface dataset:
Efficient and Correct Execution of Parallel Programs That Share Memory

In this paper we consider an optimization problem that arises in the execution of parallel programs on shared-memory multiple-instruction-stream, multiple-data-stream (MIMD) computers. A program on such machines consists of many sequential program segments, each executed by a single processor. These segments interact as they access shared variables. Access to memory is asynchronous, and memory accesses are not necessarily executed in the order they were issued. An execution is correct if it is sequentially consistent: It should seem as if all the instructions were executed sequentially, in an order obtained by interleaving the instruction streams of the processors. Sequential consistency can be enforced by delaying each access to shared memory until the previous access of the same processor has terminated. For performance reasons, however, we want to allow several accesses by the same processor to proceed concurrently. Our analysis finds a minimal set of delays that enforces sequential consistency. The analysis extends to interprocessor synchronization constraints and to code where blocks of operations have to execute atomically. We use a conflict graph similar to that used to schedule transactions in distributed databases. Our graph incorporates the order on operations given by the program text, enabling us to do without locks even when database conflict graphs would suggest that locks are necessary. Our work has implications for the design of multiprocessors; it offers new compiler optimization techniques for parallel languages that support shared variables.
Body Image and Day‐to‐Day Social Interaction

Participants maintained a social interaction diary and completed a measure of body image. Body image was found to have three factors, body attractiveness, social attractiveness (how attractive people believed others found them to be), and general attractiveness. For both men and women, self-perceptions of body attractiveness and of social attractiveness were positively related to the intimacy they found in interaction. Self-perceptions of social attractiveness were positively related to women’s confidence in social interaction and their perceived influence over interaction, whereas for men, confidence and influence were unrelated to social attractiveness. For both men and women, body image was unrelated to how enjoyable people found interactions to be and was weakly related to how responsive they felt others were to them. For both men and women, body image was also unrelated to how socially active people were and to the relative distribution of same- and opposite-sex interactions.
Chromosome studies in stauroderus (an orthopteron)

S. scalaris (Orthoptera, Truxalinae) from Scotland and Siberia has a diploid complex of seventeen chromosomes (six V-multiples and eleven rods). Each element possesses a polar or proximal granule recognizable throughout all stages of prophase of the first spermatocyte and in all other stages when concentration is not so great as to mask it. In telophase of the first spermatogonial division the polar granules may fuse into a single body or into several irregular bodies (chromoplasts of Eisen and Janssens). By the end of the diatene stage the chromoplast is completely resolved into its component granules which are clearly recognizable as the proximal parts of the rods (ends) and of the multiples (mid-portions). The accessory chromosome is precocious in its behavior and differential in structure at all stages, but its peculiarities are most marked in metaphase of the first spermatocyte where it becomes a non-chromatic vesicle with peripheral granules and chromatic core. Each multiple arises from the permanent fusion of two rod elements. They differ from those in other members of the same sub-family in diakinesis (eight-strand or octad stage) in that proximal concentration extends almost throughout the multiple.
Crystallographic description of phases in the Y-Ba-Cu-O superconductor

Single-crystal x-ray techniques were used to determine two structures that comprise the Y-Ba-Cu-O superconductor. A green phase has the orthorhombic ${\mathrm{Y}}_{2}$${\mathrm{BaCuO}}_{5}$ structure. An opaque phase (${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{6+\mathrm{x}}$, 0\ensuremath{\le}x\ensuremath{\le}1.0) is tetragonal (a=3.859 A\r{}, c=11.71 A\r{}; space group P4\ifmmode\bar\else\textasciimacron\fi{}m2;Z=1). The structure is related to a 1:1:3 AB${\mathrm{O}}_{3}$ perovskite: Ba and Y order in A sites and Cu is in B sites. Systematic oxygen vacancies between adjacent copper atoms lead to a fivefold-coordinate Cu in proximity to Y and a twofold-coordinate Cu in the vicinity of the Ba site.
The effect of eyestalk extirpation on metamorphosis of megalops of the blue crab, Callinects sapidus Rathbun

Abstract One or two eyestalks were removed from the megalops of the crab Callinectes sapidus Rathbun, reared under controlled laboratory conditions, on days 0–5 following the final zoeal molt. Following metamorphosis, the post-larval stages were maintained and measured over 4–6 consecutive molting periods. From these studies the following conclusions may be made: ( 1 ) Metamorphosis to the first crab stage is accelerated considerably by the extirpation of both eyestalks within 12 hours following the final zoeal molt. Removal of both eyestalks on days 1–5 following the final zoeal molt does not affect metamorphosis. Removal of one eyestalk on day 0 does not affect metamorphosis, but extirpation on days 1–4 significantly delays it. ( 2 ) Removal of one eyestalk on days 0–5 following the final zoeal molt accelerates some post-larval molts, but the effect is not persistent. Post-larval molting occurs more frequently in crabs which metamorphose from megalops with both eyes removed on day 0 following the final zoeal molt. Crabs which metamorphose from megalops with both eyes removed on days 1–5 do not show any acceleration in post-larval molting frequency. These results are not completely compatible with the current concept which restricts the control of molting to the x organ of the eyestalks and the Y organs. ( 3 ) Crabs which metamorphose from megalops without both eyestalks show a greater increase in size than crabs of the control series. Even if molting were not accelerated, as in crabs which metamorphosed from megalops with both eyes removed on days 1–5, there is a greater increase in size at the time of molting. Thus, while molting and growth are normally associated, the hormones which control the two processes are not identical. ( 4 ) Crabs which metamorphosed from megalops with both eyes removed showed a considerably higher mortality than either the crabs with one eye removed or the control crabs. ( 5 ) The results suggest that endocrines other than the molt-inhibiting hormone of the x organ and the molt-accelerating hormone of the Y organ are involved in both metamorphosis of the megalops and in post-larval molting. Additional evidence is needed to describe the source of these hormones and to define their role in metamorphosis and molting.
Violence Against Women: The Phenomenon of Workplace Violence Against Nurses

Registered nurses have been the recipients of an alarming increase in workplace violence (WPV). Emergency and psychiatric nurses have been found to be the most vulnerable and yet few solid reporting procedures exist to fully account for a true number of incidents. Further compounding the problem is the lack of a standard definition of violence to guide reporting procedures, interventions, legislation, and research. While there are certain risk factors that not only predispose the nurse and the patient to WPV, research continues to attempt to parse out which risk factors are the key determinants of WPV and also which interventions prove to be significant in reducing WPV. The nursing shortage is expected only to increase; recruitment and retention of qualified staff members may be deterred by WPV. This necessitates focused research on the phenomenon of workplace violence in health care.
Usability Testing: Making it Work for the Army

During an early formative usability test, representative end-users perform a set of tasks using a prototype or simulation of a system. While performing tasks and thinking aloud, a skilled specialist observes and takes notes recording how easily a participant performs the tasks and logging issues encountered. Sessions are conducted in a usability test lab, while interested parties watch from a separate observation room through a one-way mirror. Due to cost, schedule, and resource constraints many elements of conventional usability testing are not viable for use when testing equipment with Warfighters. To overcome these challenges and meet the needs of system developers, usability test procedures were modified and hybrid solutions developed. Descriptions and examples of these modifications are provided as are lessons learned and insights gained through their use during the course of seven usability tests.
Mating-Inhibition Field Tests Using Disparlure, the Synthetic Gypsy Moth Sex Pheromone

Disparlure-treated hydrophobic filter paper was distributed by aircraft in 40-acre plots at the rate of 20 mg/acre (about 5400 pieces 1/4-in-square/acre, each piece containing about 4 µg of disparlure). For 6 days this treatment almost completely prevented released males of Porthetria dispar (L.) from locating traps baited either with a single live virgin female or with 10 µg of disparlure. Three weeks after applying the lure-treated paper, captures of released male moths in the treated areas, when compared with captures of released moths in untreated areas, were depressed 93 and 67% in plots containing traps baited with live females and disparlure, respectively. The disparlure-baited traps consistently attracted more males than those baited with live females. Traps placed at a height of 1 m generally caught more moths than those placed at a level of 4 to 5 m. Captures of male moths were recorded 1 and 24 hr after release of the males; most captures were made within the 1st hour. The data indicate that the use of disparlure in this manner to prevent gypsy moth mating in very light infestations shows high promise, hut that a disparlure formulation of greater persistence is needed if mating is to be depressed adequately for an entire season with a single application.
EFFECT OF FREEZING ON THE MECHANICAL PROPERTIES OF LAMB LOIN CHOPS

The effect of freezing on the mechanical properties of lamb chops was evaluated. Fresh and frozen lamb chops (20 pairs) were cooked, cooled and tested in a constant loading rate, pneumatically operated testing machine with output fed into an X-Y plotter. Core samples (1.27 cm diam) from the longissimus dorsi muscle of the cooked lamb chops were sheared at the rate of 5 cm/min by use of a Warner-Bratzler shearing device in the testing machine. From the force-deformation curves, the following values were determined: (1) force, stress, deformation and strain at point of inflection, bioyield and rupture points; (2) area under the curve; (3) apparent modulus of elasticity; and (4) secant modulus. The values for apparent modulus of elasticity, deformation, strain, secant modulus and area under the force-deformation curve to the point of inflection were significantly (P < 0.05) different for fresh and frozen chops. Analysis of force data and stress values indicated that these values were not influenced significantly by freezing and subsequent frozen storage.
The Fly CAMTA Transcription Factor Potentiates Deactivation of Rhodopsin, a G Protein-Coupled Light Receptor

Control of membrane-receptor activity is required not only for the accuracy of sensory responses, but also to protect cells from excitotoxicity. Here we report the isolation of two noncomplementary fly mutants with slow termination of photoresponses. Genetic and electrophysiological analyses of the mutants revealed a defect in the deactivation of rhodopsin, a visual G protein-coupled receptor (GPCR). The mutant gene was identified as the calmodulin-binding transcription activator (dCAMTA). The known rhodopsin regulator Arr2 does not mediate this visual function of dCAMTA. A genome-wide screen identified five dCAMTA target genes. Of these, overexpression of the F box gene dFbxl4 rescued the mutant phenotypes. We further showed that dCAMTA is stimulated in vivo through interaction with the Ca(2+) sensor calmodulin. Our data suggest that calmodulin/CAMTA/Fbxl4 may mediate a long-term feedback regulation of the activity of Ca(2+)-stimulating GPCRs, which could prevent cell damage due to extra Ca(2+) influx.
Separation and identification of Neurospora phosphatases by polyacrylamide gel electrophoresis.

Abstract Appropriate conditions for the successful separation of Neurospora crassa phosphatases by polyacrylamide gel electrophoresis have been developed. A neutral range electrophoresis buffer is essential for separation. Procedures are described for identification of acid and alkaline phosphatases. Four of the phosphatase bands separated correspond to phosphatases characterized by previous investigators, while a fifth band appears to be a phosphatasc isozyme not previously reported.
Improvements in Channel Catfish Growth after Two Generations of Selection and Comparison of Performance Traits among Channel Catfish, Blue Catfish, and Hybrid Catfish Fingerlings in an Aquarium Rack System

Abstract A 9-week growth study was conducted to compare the fingerling performance of two genetic groups of channel catfish Ictalurus punctatus (U.S. Department of Agriculture [USDA] 103 and USDA303) with that of blue catfish I. furcatus and their hybrid in an aquarium rack system. Fish of approximately 20 g were randomly selected from multifamily populations and acclimated to the aquarium rack system for 2 weeks prior to the start of the 9-week study. Differences in growth indices, feed and protein efficiency, nitrogen retention, whole-body proximate composition, and plasma cortisol levels were determined at the completion of the study. The USDA303 channel catfish gained significantly more weight and consumed more feed than each of the other genetic groups. Feed and protein efficiency were similar among USDA103, USDA303, and hybrid catfish but were lower for blue catfish. Nitrogen retention was highest for hybrid catfish and lowest for blue catfish. No differences in final body composition were observed ...
Characterization of Compost From a Pilot Plant-Scale Composter Utilizing Simulated Solid Waste

Abstract A pilot plant-scale composter using simulated solid waste was developed to test the fate of consumer products such as disposable diapers. The simulated waste consisted of a mixture of rabbit chow (which included alfalfa), shredded newspaper, sand, and composted cow manure. The compost mass self-heated from an ambient temperature of 27°C to about 55°C in the first 24 h. Dissolved ammonia levels, high in the early stages of the process, began to decrease after about 4 weeks as nitrate concentration began to increase. Both volatile solids and carbon:nitrogen ratios exhibited gradual decreases with time. Microbial biomass, esterase activity, cellulose mineralization, direct microscopic counts (AODC), and relative APIZYM enzyme activity increased significantly in the first several days, and maintained higher levels than initial measurements throughout the 22-week testing period. We concluded that the simulated solid waste underwent physical, chemical, and microbiological changes that would be expected to occur in municipal solid waste in a full-scale composting system. The pilot plant-scale composter should prove to be a valuable tool in assessing the fate of products and materials under simulated compost conditions.
Entraining power-dropout events in an external-cavity semiconductor laser using weak modulation of the injection current

We measure experimentally the effects of injection current modulation on the statistical distribution of time intervals between power-dropout events occuring in an external-cavity semiconductor laser operating in the low-frequency fluctuation regime. These statistical distributions are sensitive indicators of the presence of pump current modulation. Under most circumstances, we find that weak low-frequency (in the vicinity of 19 MHz) modulation of the current causes the dropouts to occur preferentially at intervals that are integral multiples of the modulation period. The dropout events can be entrained by the periodic perturbations when the modulation amplitude is large (peak-to-peak amplitude /spl ges/8% of the dc injection current). We conjecture that modulation induces a dropout when the modulation frequency is equal to the difference in frequency between a mode of the extended cavity laser and its adjacent antimode. We also find that the statistical distribution of the dropout events is unaffected by the periodic perturbations when the modulation frequency is equal to the free spectral range of the external cavity. Numerical simulations of the extended-cavity laser display qualitatively similar behavior. The relationship of these phenomena to stochastic resonance is discussed and a possible use of the modulated laser dynamics for chaos communication is described.
Problem-Solving Therapy for Subthreshold Depression in Home Healthcare Patients With Cardiovascular Disease

Background: Randomized trial evaluated problem-solving therapy in home care (PST-HC) for homebound older adults with cardiovascular disease receiving acute home care services. This study hypothesized that compared with usual care plus education intervention, home-based PST-HC would significantly reduce depression and anxiety scores, lead to improved quality of life, and greater satisfaction with treatment among elderly with cardiovascular disease. Methods: Thirty-eight participants were recruited from a university-affiliated home healthcare agency for the trial. Six 1-hour PST-HC sessions included depression education, problem-solving skills, pleasurable activity scheduling, homework, and weekly telephone calls over a 6-week period. The control comparison group received usual care plus two sessions of education and a depression brochure. Outcome measures included the Beck Depression Inventory, Hamilton Rating Scale for Depression, Beck Anxiety Inventory, and the short form (SF)-36 health status measure. After the intervention, both groups completed the Patient Satisfaction Questionnaire. Results: Compared with the control group, the PST-HC group showed a significant decrease in depression but not anxiety scores. The PST-HC group generally reported more favorable satisfaction with treatment than the control group. The PST-HC group improved significantly, when compared with the control group in only two of eight SF-36 subscales: mental health and emotional role function. Conclusions: The brief PST-HC intervention demonstrated that depression improved among home care elderly. However, there was no change in six of eight health status measures or anxiety level. Authors discuss integrating interdisciplinary depression care in the home care setting.
Design of Dynamic Freeform Optics

Multi-element freeform systems with controlled relative motions enable dynamic optical functionality. In this paper, we discuss design approaches for such systems and explore examples ranging from the varifocal lenses to novel beamshaping elements.
The Inflation-Output Variability Tradeoff and Monetary Policy: Evidence from a GARCH Model

This paper empirically investigates the Taylor curve volatility tradeoff in light of the stochastic behavior of the conditional variances of output and inflation. Stressing structural instability between periods before and after the 1979-1982 monetary policy regime change, I implement a bivariate generalized autoregressive conditional heteroskedasticity model to capture the output-inflation variability tradeoff and to explore the plausible impact of a change in the federal funds rate on the two conditional volatilities. I further evaluate the impacts of anticipated and unanticipated policy actions measured by two alternative policy reaction functions---one from a vector-autoregression-based reduced-form equation and another based on the Taylor rule. In addition to showing a volatility tradeoff relationship, the empirical model reveals different magnitudes of policy effects on output and inflation volatility across the two sample periods.
225Ac and 223Ra production via 800 MeV proton irradiation of natural thorium targets.

Abstract Cross sections for the formation of 225,227Ac, 223,225Ra, and 227Th via the proton bombardment of natural thorium targets were measured at a nominal proton energy of 800 MeV. No earlier experimental cross section data for the production of 223,225Ra, 227Ac and 227Th by this method were found in the literature. A comparison of theoretical predictions with the experimental data shows agreement within a factor of two. Results indicate that accelerator-based production of 225Ac and 223Ra is a viable production method.
The effects of age, stimulus intensity, and training trials on mediated stimulus generalization☆☆☆

Abstract Three experiments involving the mediated stimulus generalization (MSG) of verbs scaled for hostile intensity are described. Experiment I contrasted gradients for two age groups (9-2 and 11-8). The younger S s had a higher, but not broader, gradient. Experiment II was derived from the Stimulus Intensity Dynamism (V). One-half of the S s (Group H) were trained to make a lever pull to intensely hostile verbs and generalized down the intensity scale. The remaining S s (Group M) were trained to mildly hostile verbs and generalized up the intensity scale. The Group M gradient was higher than that of Group H and consistent with (V). Experiment III contrasted the MSG gradients for groups receiving 4 and 8 reinforced training trials. As predicted the Group 8 gradient was higher and broader.
THE EVOLUTION OF HUMPHREY‐HAWKINS*

Humphrey-Hawkins, enacted into law as the Full Employment and Balanced Growth Act of 1978, is the most important step the Federal government has taken for overall economic coordination since passage of the Employment Act of 1946. The centerpiece of the new law is specific goals for unemployment and inflation. All Federal programs and policies are to work toward achieving a 3 percent adult and 4 percent overall jobless rate within five years, and inflation rates of 3 percent by 1983 and 0 percent by 1988. The present article outlines the major changes made in Humphrey-Hawkins from its introduction in June 1974 to its enactment in October 1978, the contents of the Full Employment and Balanced Growth Act of 1978, and the politics surrounding its passage.
Coalescence of viscous drops with surfactants

Abstract Drop coalescence is a familiar event in both nature and technology, from spray and atomization systems to the production of food emulsions. It is well known that surfactants – which are ubiquitous contaminants and routinely used as industrial additives – play an important role in preventing drop coalescence. Little is known, however, about the mechanisms of coalescence after surfactant-laden drops make contact. Here we analyze these mechanisms using direct numerical simulation. Results show that due to the uneven contraction of the interface the surfactant accumulates on the liquid meniscus bridge joining the drops. Simulations further reveal that the accumulation is hampered by Marangoni stresses induced, in turn, by the uneven surfactant distribution. These entwined mechanisms control the rate at which the drops coalesce by modulating the pull of surface tension on the meniscus bridge.
Tritium and argon radioactivties in lunar material.

Tritium and argon radioactivities, attributable to galactic and solar cosmic-ray interactions, were measured in lunar soil and in three lunar rocks. The tritium in the soil, 325 ± 17 disintegrations per minute per kilogram, is slightly higher than that in the rocks, 212 to 250 dpm/kg. For two rocks, the tritium was combined with the helium-3 in order to calculate exposure ages of 375 ± 40 and 205 ± 25 million years. The argon-37 radioactivities, 21.0 to 27.2 dpm/kg, and the argon-39 radioactivities, 12.1 to 16.4 dpm/kg, are slightly higher than those in stony meteorites. Higher exposure ages were obtained from the argon isotopes than from tritium and helium-3. On the basis of the known galactic cosmic-ray flux and the known cross section, at least half of the observed radioactivities are produced by solar cosmic rays.
Epilogue: Symposium on the adult with postoperative congenital heart disease

The stellar roster of adult and pediatric cardiologists, as well as cardiovascular surgeons contributing to this Symposium guarantees its excellence. The quality of the presentations, as well as the broad areas the editors targeted for discussion, leaves little to be said in the Epilogue. I have chosen to speculate briefly about the future of adults who were operated on during childhood for their congenital cardial malformation in the 1950s and 1960s and to attempt to contrast their fate with those children whose surgery was, or will be, performed in the 1970s and 1980s.
Selective cleavage of O-acyl protecting groups from blocked deoxyribotides

Abstract Selective hydrolysis of the 3′- O -acetyl groups in the 5′- P -cyanoethyl-blocked deoxyribonucleotides, commonly used in oligomer synthesis by the diester method, can be achieved by mild hydrolysis with aqueous ammonia in pyridine for a brief period of time. The 3′- O -isobutyryl group is much more resistant. Conditions for 3′-unblocking of the four commonly used protected monomers as well as a model oligomer, d(CNEtpbzA-ibuG)Ac, are described.
Alpha radiation induced production of HNO3 during dissolution of Pu compounds (1)

Abstract Air-equilibrated suspensions of 238 Pu and 239 Pu compounds in dilute salt solutions produced HNO 3 at a rate which increased with the H + concentration.
Application of Dual Hologram Interferometry to Wind-Tunnel Testing

T study shows that dual hologram interferometry can be used to accurately measure local densities in wind-tunnel experiments, and that this technique does not suffer from some of the serious limitations of previous interferometric methods. A pulsed ruby laser is used as the light source so that highfrequency turbulence in the flow can be instantaneously recorded, and hence, frozen in time. The unique feature of dual hologram interferometry is that the no flow and flow conditions are recorded at different times on separate holograms. Because of this, movement between exposures is not recorded in the interferogram, and therefore, the method is not sensitive to wind-tunnel vibration. The images are interfered upon reconstruction, and the fringe configuration is controlled by precisely varying the orientation of the two holograms with respect to each other. ~ The heart of a practical, operational system is the dual hologram plate holder which is used to hold and precisely align the two holograms during image reconstruction. To demonstrate the accuracy and versatility of this method, three separate Mach 3 flowfields were considered in the original paper, but only the flat plate turbulent boundary-layer results are presented here.
Avalanche ionization and dielectric breakdown in silicon with ultrafast laser pulses

Summary form only given. Data are presented that demonstrate electron production by avalanche ionization as the dominant mechanism for laser breakdown, and subsequent surface damage in silicon, for laser pulse durations in the range of 80 fs to 9 ns. Experiments are performed at 786 nm and 1.06 /spl mu/m exhibiting the correct wavelength dependence for an avalanche process.
Mitochondria-derived ROS bursts disturb Ca2+ cycling and induce abnormal automaticity in guinea pig cardiomyocytes: a theoretical study

Mitochondria are in close proximity to the redox-sensitive sarcoplasmic reticulum (SR) Ca2+ release [ryanodine receptors (RyRs)] and uptake [Ca2+-ATPase (SERCA)] channels. Thus mitochondria-derived...
Portlandia proctorii (Rubiaceae, Catesbaeeae), a new combination for a narrow endemic Jamaican species

Abstract Portlandia proctorii (Rubiaceae, Catesbaeeae), a new combination for a narrow endemic Jamaican species. Brittonia 55: 233–239. 2003.—Aiello, in a revision of Portlandia and related genera, recognized two varieties in Portlandia coccinea Sw. based on leaf shape and geographic distribution. After detailed studies of herbarium specimens, recent observations of both varieties in their natural environment and in cultivation, and a phylogenetic analysis, it became evident that P. coccinea var. proctorii Aiello should be treated as a separate species with corollas shorter and of a different shape than those of var. coccinea. Portlandia proctorii is presented as a new combination. A key for the two species, descriptions and illustrations are included.
Lick Observatory Charge-Coupled-Device Data Acquisition System

The Lick Observatory CCD data acquisition system is described, with some observational results to illustrate the system capability. The electronics for the CCD are subdivided into those attached to the dewar, a 'smart' controller near the dewar, and a computer connected by serial link to the smart controller. Software for the controller is in assembler code, while the software for data acquisition and on-line analysis is written in C and uses the UNIX operating system. The computers and controllers are programmed to recognize and operate several different types of CCD. Three separate instruments that use the CCDs are described briefly, together with examples of the data they produce.
Genetic and Epigenetic Regulation of the FLO Gene Family Generates Cell-Surface Variation in Yeast

The FLO gene family of Saccharomyces cerevisiae includes an expressed gene, FLO11, and a set of silent, telomere-adjacent FLO genes. This gene family encodes cell-wall glycoproteins that regulate cell-cell and cell-surface adhesion. Epigenetic silencing of FLO11 regulates a key developmental switch: when FLO11 is expressed, diploid cells form pseudohyphal filaments; when FLO11 is silent, the cells grow in yeast form. The epigenetic state of FLO11 is heritable for many generations and regulated by the histone deacetylase (HDAC) Hda1p. The silent FLO10 gene is activated by high-frequency loss-of-function mutations at either IRA1 or IRA2. FLO10 is regulated by the same transcription factors that control FLO11: Sfl1p and Flo8p, but is silenced by a distinct set of HDACs: Hst1p and Hst2p. These sources of epigenetic and genetic variation explain the observed heterogeneity of cell-surface protein expression within a population of cells derived from a single clone.
Role of condensed-phase reactions in ignition and deflagration of ammonium perchlorate propellants

The contribution of exotherme, condensed-phase reactions to ignition and deflagration of propellants is examined. Measurements of the rates of heat release, thermal diffusivity, burning rate and ignition are combined to demonstrate the role of reactions in propellants made up of powdered ammonium perchlorate and catalysts. By means of a theoretical analysis, it is found that for the propellants under study a thermal runaway in the condensed phase can account for the ignition phenomena observed. Also, at low steady-state deflagration rates the contribution of the solid-phase reactions can be demonstrated. Some of the propellants quenched during deflagration have shown the existence of a subsurface layer, which is located in a zone at which the temperature has reached the level characteristic of the crystal transition of ammonium perchlorate.
Probability Distribution of Low Streamflow Series in the United States

Estimates of low streamflow statistics are required for a variety of water resource applications. At gauged river sites, the estimation of low streamflow statistics requires estimation of annual n-day minimum streamflows, selection of a probability distribution to describe annual minimums, and estimation of the distribution's parameters. Using L-moment diagrams, the ability of various probabil- ity distributions to describe low streamflow series was examined at 1,505 gauged river sites in the United States. A weighted distance statistic was developed to compare the goodness-of-fit of different probability distributions for describing low streamflow series. Com- pared to perennial streamflow sites, a shift of L-moments ratios was observed at intermittent river sites where discharge is sometimes reported as zero. An analytical experiment compared the observed shifts in L-moment ratios at intermittent sites with theoretical L-moment ratio shifts for a number of real- and log-spaced probability distributions. Results of these experiments indicate that Pearson Type III and the 3-parameter lognormal distributions should be the recommended distributions for describing low streamflow statistics in the United States at intermittent and nonintermittent ~perennial! sites, respectively.
Hybrid Simulation Theory for Continuous Beams

AbstractHybrid simulation is an experimental technique involving the integration of a physical system and a computational system with the use of actuators and sensors. This method has a long history in the experimental community and has been used for nearly 40 years. However, there is a distinct lack of theoretical research on the performance of this method. Hybrid simulation experiments are performed with the implicit assumption of an accurate result as long as sensor and actuator errors are minimized. However, no theoretical results confirm this intuition nor is it understood how minimal the error should be and what the essential controlling factors are. To address this deficit in knowledge, this study considers the problem as one of tracking the trajectory of a dynamical system in a suitably defined configuration space. To make progress, the study strictly considers a theoretical hybrid system. This allows for precise definitions of errors during hybrid simulation. As a model system, the study looks at...
Quantitative assessment of postural stability using accelerometer and gyroscopic data during balance error scoring system

Objective The aim of this study was to validate a portable method of objectively quantifying postural stability using accelerometer and gyroscopic data from the iPad2 during BESS. Design Participants completed the six 20 s BESS conditions. BESS errors were recorded by trained evaluators. Linear and angular acceleration were simultaneously collected via the iPad2 accelerometer and gyroscope. Setting Academic medical center. Participants Fifty healthy participants aged 14–25 with no concussion in previous 6 months. Main Outcome Measurements The primary outcome measures were evaluator-reported errors and natural-logarithmic volume of a 3D ellipsoid (iVE) encompassing 95% of postural sway data. The iVE characterises movement along anterior–posterior, medial-lateral, and trunk-rotational movement axes. It was hypothesised that iVE would provide a more sensitive assessment of postural stability than traditional BESS error scoring. Results For the two double-leg stance conditions, BESS error scores were nearly identical, as few participants made errors. However, iVE data indicated a significant difference in stability between these conditions, as iVE for double-leg stance on firm surface was 0.3±0.16 s 3 while iVE on foam was 3.4±0.16 s 3 . Conclusions The objective data gathered using a consumer electronics device provides a reliable and valid assessment of postural stability and increases the sensitivity of the BESS. Accordingly, it is recommended that all six BESS conditions be completed in order to fulfill the current Zurich recommendation of a comprehensive balance assessment. We are currently using the ‘C3 App’ and BESS in the collection of baseline data in 12 000 high school and college athletes.
Organization Properties and Sex-Segregation in the Underworld: Building a Sociological Theory of Sex Differences in Crime

In this report I examine institutionalized sexism in the underworld. Crime in its more organized and lucrative dimensions is virtually a male phenomenon. Still, sexsegregation in the underworld is variable, being more common in some crime groups than in others. To explain this, I offer a series of propositions and hypotheses linking female access to crime groups to their structure and methods of operation. The proposed framework elaborates on Cloward's opportunity theory by discriminating among illegitimate opportunities depending on whether they are for underworld or upperworld crime, for organized or unorganized crime, for lucrative or petty crime. The scheme can be extended, as well, to an interpretation of race and kinship segregation in the underworld and to an interpretation of sex differences in upperworld crime. My purpose in this report is to show how sex differences in crime are a function of underworld culture and organization and to offer a series of propositions which link properties of crime organizations to criminal roles of women. 1 I use the literature on criminal subcultures and crime organizations and also apply theory from the sociology of occupations and organizations2 to explain (1) the existence of sex-segregation in organized criminal enterprise, resulting in (a) the exclusion or underrepresentation of women in organized crime and (b) their allocation to less-valued roles within crime groups when they are allowed to participate; and (2) the variability of sexsegregation across the spectrum of organized crime activities. In examining these two, related issues, I focus mainly on the social and work relations of the underworld by which crime is organized and through which social positions of individual criminals and crime groups become differentiated. Whatever the historical reasons, roles and struc*For their helpful comments on earlier drafts of this paper I thank Lynne Appleton, Richard Bord, Gilbert Geis, John Hepburn, Roland Pellegrin, Larry Rhoades, Francis Slim Renee Hoffman Steffensmeier, Robert Terry, Mark Warr, and anonymous referees. ?' 1983 The University of North Carolina Press
Measuring the benefit of service oriented student design projects

The State of Tennessee Department of Education provides grant support to the University of Tennessee at Chattanooga (UTC) to design, prototype, test, evaluate and disseminate products, procedures, and services that apply adaptive and assistive technologies to children with special needs. Eight to sixteen projects have been completed by freshman and upper level students each year since the fall of 2005. The academic outcome of these projects is an opportunity for students to experience the design process, aid someonepsilas ability to be independent, and learn how engineering can benefit our society. The students who participate in these projects informally express they are motivated by knowing they have designed a device that can improve the life of a child. A recent formal survey of those students who have participated in these projects confirms this statement. It also presents some interesting findings with respect to why students choose particular projects to participate in and what they believe they have learned from the projects that is most beneficial to them.
A mathematical model of intrahost pneumococcal pneumonia infection dynamics in murine strains

The seriousness of pneumococcal pneumonia in mouse models has been shown to depend both on bacterial serotype and murine strain. We here present a simple ordinary differential equation model of the intrahost immune response to bacterial pneumonia that is capable of capturing diverse experimentally determined responses of various murine strains. We discuss the main causes of such differences while accounting for the uncertainty in the estimation of model parameters. We model the bacterial population in both the lungs and blood, the cellular death caused by the infection, and the activation and immigration of phagocytes to the infected tissue. The ensemble model suggests that inter-strain differences in response to streptococcus pneumonia inoculation reside in the strength of nonspecific immune response and the rate of extrapulmonary phagocytosis.
Robust recognition of physical team behaviors using spatio-temporal models

This paper presents a framework for robustly recognizing physical team behaviors by exploiting spatio-temporal patterns. Agent team behaviors in athletic and military domains typically exhibit an observable structure characterized by the relative positions of teammates and external landmarks, such as a team of soldiers ambushing an opponent or a soccer player moving to receive a pass. We demonstrate how complex team relationships that are not easily expressed by region-based heuristics can be modeled from data and domain knowledge in a way that is robust to noise and spatial variation. To represent team behaviors in our domain of MOUT (Military Operations in Urban Terrain) planning, we employ two classes of spatial models: 1) team templates that encode static relationships between team members and external landmarks; and 2) spatially-invariant Hidden Markov Models (HMMs) to represent evolving agent team configurations over time. These two classes of models can be combined to improve recognition accuracy, particularly for behaviors that appear similar in static snapshots. We evaluate our modeling techniques on large urban maps and position traces of two-person human teams performing MOUT behaviors in a customized version of Unreal Tournament (a commercially available first-person shooter game).
The role of broca's area in sentence comprehension

The role of Broca's area in sentence processing has been debated for the last 30 years. A central and still unresolved issue is whether Broca's area plays a specific role in some aspect of syntactic processing (e.g., syntactic movement, hierarchical structure building) or whether it serves a more general function on which sentence processing relies (e.g., working memory). This review examines the functional organization of Broca's area in regard to its contributions to sentence comprehension, verbal working memory, and other multimodal cognitive processes. We suggest that the data are consistent with the view that at least a portion of the contribution of Broca's area to sentence comprehension can be attributed to its role as a phonological short-term memory resource. Furthermore, our review leads us to conclude that there is no compelling evidence that there are sentence-specific processing regions within Broca's area.
Measurement of Adhesive Forces between Individual Staphylococcus aureus MSCRAMMs and Protein-Coated Surfaces by Use of Optical Tweezers

The force required to rupture bonds between individual Staphylococcus aureus MSCRAMMs and surfaces coated with extracellular matrix molecules has been quantified by using optical tweezers. The observed binding forces between fibrinogen or fibronectin and S. aureus MSCRAMMs occurred as an approximate integer multiple of 20 or 25 pN, respectively.
Updating users about time critical events

During unexpected events such as natural disasters, individuals rely on the information generated by news outlets to form their understanding of these events. This information, while often voluminous, is frequently degraded by the inclusion of unimportant, duplicate, or wrong information. It is important to be able to present users with only the novel, important information about these events as they develop. We present the problem of updating users about time critical news events, and focus on the task of deciding which information to select for updating users as an event develops. We propose a solution to this problem which incorporates techniques from information retrieval and multi-document summarization and evaluate this approach on a set of historic events using a large stream of news documents. We also introduce an evaluation method which is significantly less expensive than traditional approaches to temporal summarization.
Blinking mechanism of colloidal semiconductor quantum dots: Blinking mechanisms

Nanoscale semiconductor quantum dots in colloidal suspensions are observed to blink with off times, τoff, that scale as 1/τ 3/2. In this paper, it is shown by relating the fluctuations of the surface charge density on the quantum dot to fluctuations in the double layer potential, that the related fluctuations in the barrier potential have exactly the functional form needed to result in an inverse-power-law distribution for off times.
A new twist in the educational tracking debate

Abstract Recently, the practice of tracking has been receiving more attention by both educators and researchers and some have questioned the policy merit. One of the strongest arguments against tracking is that it creates homogenous classes according to ability and, therefore, reduces the positive spillover effect referred to as a peer effect. While peer effects have been found to be an important input into the production of education no study has specifically examined whether these effects are more or less prevalent in classes where tracking occurs. Utilizing individual student level data, this current research examines whether the peer effect occurs in cases in which tracking is present. The results suggest that the use of tracking diminishes the impact peers have on student achievement for low- and average-ability students while the peer effect is unaffected by tracking for high-ability students.
Effects of DNA methylation on nucleosome stability

Methylation of DNA at CpG dinucleotides represents one of the most important epigenetic mechanisms involved in the control of gene expression in vertebrate cells. In this report, we conducted nucleosome reconstitution experiments in conjunction with high-throughput sequencing on 572 KB of human DNA and 668 KB of mouse DNA that was unmethylated or methylated in order to investigate the effects of this epigenetic modification on the positioning and stability of nucleosomes. The results demonstrated that a subset of nucleosomes positioned by nucleotide sequence was sensitive to methylation where the modification increased the affinity of these sequences for the histone octamer. The features that distinguished these nucleosomes from the bulk of the methylation-insensitive nucleosomes were an increase in the frequency of CpG dinucleotides and a unique rotational orientation of CpGs such that their minor grooves tended to face toward the histones in the nucleosome rather than away. These methylation-sensitive nucleosomes were preferentially associated with exons as compared to introns while unmethylated CpG islands near transcription start sites became enriched in nucleosomes upon methylation. The results of this study suggest that the effects of DNA methylation on nucleosome stability in vitro can recapitulate what has been observed in the cell and provide a direct link between DNA methylation and the structure and function of chromatin.
Response to Letter by Hadjiev and Mineva

Response: We thank Drs Hadjiev and Mineva for their comments on our article investigating the relationship between intima media thickness (IMT) and regional cerebral blood flow (rCBF) in older adults. This study evaluated nondemented participants in the Baltimore Longitudinal Study of Aging who underwent annual neuropsychological testing, neurological examination, interval medical history, and medication review.1–3 Changes in IMT have been associated with multiple cardiovascular risk factors and medications.4,5 Twenty-eight of 73 participants in our study were on antihypertensive medications at the time of study (13 on calcium channel blockers, 7 on β-blockers, 9 …