cssi/SciSciGPT-SciSciNet huggingface dataset:
A learning heuristic for space mapping and searching self-organizing systems using adaptive mesh refinement

Abstract In a complex self-organizing system, small changes in the interactions between the system's components can result in different emergent macrostructures or macrobehavior. In chemical engineering and material science, such spontaneously self-assembling systems, using polymers, nanoscale or colloidal-scale particles, DNA, or other precursors, are an attractive way to create materials that are precisely engineered at a fine scale. Changes to the interactions can often be described by a set of parameters. Different contiguous regions in this parameter space correspond to different ordered states. Since these ordered states are emergent, often experiment, not analysis, is necessary to create a diagram of ordered states over the parameter space. By issuing queries to points in the parameter space (e.g., performing a computational or physical experiment), ordered states can be discovered and mapped. Queries can be costly in terms of resources or time, however. In general, one would like to learn the most information using the fewest queries. Here we introduce a learning heuristic for issuing queries to map and search a two-dimensional parameter space. Using a method inspired by adaptive mesh refinement, the heuristic iteratively issues batches of queries to be executed in parallel based on past information. By adjusting the search criteria, different types of searches (for example, a uniform search, exploring boundaries, sampling all regions equally) can be flexibly implemented. We show that this method will densely search the space, while preferentially targeting certain features. Using numerical examples, including a study simulating the self-assembly of complex crystals, we show how this heuristic can discover new regions and map boundaries more accurately than a uniformly distributed set of queries.
Characterization of Ion Profiles in Light-Emitting Electrochemical Cells by Secondary Ion Mass Spectrometry

Ion profiles in polymer light-emitting electrochemical cells are known to significantly affect performance and stability, but are not easily measured. Here, secondary ion mass spectrometry is used to investigate ion profiles in both dynamic and chemically fixed junction devices. Results indicate lower reversibility of dynamic junctions and a more significant time delay for ion redistribution than previously expected, but confirm the complete immobilization of ions in chemically fixed junction devices. When compared with prior studies analyzing the electric field profiles in similar devices, these results help to elucidate the roles of ion distribution and electrochemical doping in LECs.
Field-cage and laboratory evaluations of semiochemical-based baits for managing western corn rootworm (Coleoptera: Chrysomelidae).

Adult western corn rootworms, Diabrotica virgifera virgifera LeConte, were offered baits containing toxicant (carbaryl), a feeding stimulant (the curcurbitacins in powdered root of buffalo gourd, Cucurbita foetidissima H.B.K. [BGRPl), and a nonpheromonal attractant (TIC; 1,2,4-trimethoxybenzene, indole, and trans-cinnamaldehyde, 1:1:1). Components were encapsulated into starch granules or were formulated into particles by Bio- Control (Warwick, Queensland, Australia). In laboratory assays, baits with approximately 0.5% carbonyl and 3-5% BGRP effectively killed D. v. virgifera . Baits with these components plus 0.3-1.5% TIC were broadcast over maize in walk-in field cages; adult D. v. virgifera beetles were released, and surviving beetles were counted after 24-72 h. In cages treated at 2-32 kg/ha of starch bait, numbers of beetles were reduced by 69-94%, respectively, relative to untreated cages. Starch granules containing only carbaryl (8 kg/hal killed few or no beetles, but granules with carbaryl plus BGRP reduced numbers of beetles per cage by approximately 80% in 24 h. Efficacy of baits was not affected by adding 1.5% TIC or by phenology of maize in the cages. Activity of baits declined after 2-3 wks in the field; 3-wk-old baits reduced numbers of beetles per cage by approximately 45%, whereas freshly applied baits produced reductions of approximately 85%. Although not ideal, these formulations appear suitable for testing the concept of semiochemical-based baits on a larger scale.
Evaluating the performance of fluorescence microscopes

A simple means of evaluating the performance of fluorescence microscopes is described. The proposed test gives an overall figure of merit that takes into account all of the important instrumental parameters that determine image quality. The essence of the test is to use a specimen whose photobleaching rate is a measure of the illumination time–intensity integral. When this time–intensity integral is controlled, the signal-to-noise ratio in the image of small subresolution objects becomes a system-independent measure of light throughput, resolution and intrinsic noise.
Benefits analysis of RNP approach procedure to runway 13C at Midway airport

Advances in aircraft navigation technology (i.e. Performance Based Navigation) have enabled the implementation of precise curved path approaches (i.e., RNP 0.3 w/ RF leg approach procedure) in the terminal airspace which improve flight efficiency and allows safe navigation near high terrain obstacles and airspace occupied by other flows of air traffic. However, the adoption of these technologies by airlines has been slow and haphazard due to uncertainties in the estimates of the benefits of these new approach procedures. This paper describes a methodology and results of an analysis of RNP approach for Runway 13C at MDW airport with the objective of quantifying its benefits from an airlines perspective. Surveillance track data for aircraft flying the approaches to MDW (including aircraft equipped to fly the RNP approach) was combined with meteorological data, operational data and an aircraft fuel burn performance model to estimate the total potential benefits of the RNP approach procedure. The results show the use of RNP approach on the MDW 13C has the potential of saving on average 17.6K gallons of fuel per year for arrivals at MDW by reducing the track distance while performing precise curved path RNP approaches when wind and ceiling/visibility conditions require using the ILS 13C. This corresponds to on average $98K savings in airline direct operation costs. The precise curved path RNP approaches also make the arrival operations to runway 13C at MDW independent from operations at ORD (neighboring airport). This has a potential for saving $38K for MDW arrivals from elimination of holding patterns. The implications of these results with respect to successful implementation of RNP approach at MDW have also been discussed.
Wear of filled and unfilled dental restorative resins

Abstract The influence of double-pass sliding on the surface failure of filled and unfilled dental restorative resins was evaluated. Damage was more severe for double-pass than for single-pass sliding. Wear of restorative resins and composites was influenced by the resistance to penetration and by the mode of deformation during sliding.
Real‐time monitoring of the ring‐opening polymerization of rac‐lactide with in situ attenuated total reflectance/Fourier transform infrared spectroscopy with conduit and diamond‐composite sensor technology

Polymerization rates were proportional to initial Sn(Oct) 2 concentration at low [Sn(Oct) 2 ] 0 [PrOH] 0 values, but began to level off at higher values. When [Sn(Oct) 2 ] 0 /[PrOH] 0 was significantly greater than unity, the opposite behavior occurred. Tin(II) alkoxide concentration became limited by the initial PrOH concentration and independent of initial Sn(Oct) 2 concentration. Addition of 2-ethylhexanoic acid caused polymerization rate retardation, without affecting molecular weight. A control polymerization was conducted in the absence of PrOH. The molecular weight of the resulting polymer was consistent with the measured water content (3.7 wt % by Karl Fisher titration) of the as-received Sn(Oct) 2 . The polymerization rate in the absence of PrOH was slow, and this suggested that water is less efficient than an alcohol in creating polymerization-active stannyl ether bonds.
Prevalence of automated external defibrillators at cardiac arrest high-risk sites.

Objective. Automated external defibrillators (AEDs) distributed throughout communities may improve survival from cardiac arrest. The purpose of this study was to determine if AEDs were present at high-risk locations for cardiac arrest in King County, Washington. Methods. The authors compiled a list of sites based on a five-year study that identified public sites with the highest incidence of cardiac arrests in King County. They conducted a structured telephone survey with the manager, director, or owner of those high-risk sites. Results. Of the 263 identified high-risk cardiac arrest sites, we obtained information for 228 (87%) sites. Overall, 87 of 228 (38%) high-risk sites had one or more AEDs. The AED dissemination varied greatly by type of site. The airport, the two county jails, the five public sports venues, and the nine ferries/train terminals each reported at least one AED on site. In contrast, none of the 13 shelters and 19% of health clubs/gyms reported an AED on site. Nearly half (44%) of sites...
Interaction potentials and momentum transfer in ionic collisions: Uranium

The effect of elastic collisions of U/sup +/ with U, U/sup +/, and U/sup 2 +/ in a U/sup +/ plasma has been investigated. The required potential-energy curves were calculated by means of the electron-gas (Gordon-Kim-Rae) statistical method. An effective polarization potential was added to the ion-neutral potential curve. Collisional phase shifts were evaluated by the semiclassical JWKB method using a very efficient algorithm. Modifications necessary to take into account the long-range shielded Coulomb potential in ion-ion collisions are described. Momentum-transfer and viscosity cross sections, without charge transfer, are presented and their dependences on the long- and short-range potentials are examined.
A Randomized Trial About Glycemic Index and Glycemic Load Improves Outcomes Among Adults With Type 2 Diabetes

Glycemic index (GI) represents the postprandial glucose response of carbohydrate foods, and glycemic load (GL) represents the quantity and quality of carbohydrate consumed. A diet lower in GI and GL may improve diabetes management. A 9-week intervention regarding GI and GL was evaluated among adults in the age range of 40-70 years who had had type 2 diabetes > or =1 year (n = 103). Randomized pre-post test design with immediate and delayed treatment groups was employed. Dietary intake, knowledge, outcome expectations, self-efficacy, and empowerment regarding GI and GL and glucose monitoring were assessed. Four components were identified for outcome expectations using principal components analysis (dietary barrier, glycemic control, family support, and glucose monitoring), and two components were identified for self-efficacy (GI and self-regulation). Significant improvements in GI, knowledge, empowerment, self-efficacy, and outcome expectations (all p < .05) were observed except for glucose monitoring expectations. Only self-regulation efficacy significantly declined (p < .05) at the follow-up assessment in the immediate group. Nutrition education regarding GI and GL can improve dietary intake, knowledge, outcome and efficacy expectations, and empowerment for diabetes management.
Inflammatory diseases and bone health in children.

PURPOSE OF REVIEW Chronic pediatric inflammatory diseases are associated with low bone mass and fractures during childhood, and may hasten the onset of osteoporosis later in life. Proinflammatory cytokines and glucocorticoid therapy are likely key factors that impair bone accrual, along with downstream effects including malnutrition, pubertal delay, low muscle mass and physical inactivity. RECENT FINDINGS Studies have used advanced imaging to characterize deficits in trabecular and cortical bone and have evaluated the 'functional muscle-bone unit'. In general, bone strength in the appendicular skeleton is compromised because of thinner cortical bone, with a low periosteal circumference and a normal or expanded endosteal circumference. Low muscle mass likely contributes to, but does not fully account for bone deficits. Systematic efforts to define the incidence and prevalence of bone fragility in children with inflammatory conditions demonstrated that vertebral fractures occur in a significant minority of patients in association with high disease activity, glucocorticoid use, and weight gain. Lumbar spine dual X-ray absorptiometry does not consistently distinguish children with and without vertebral fractures. SUMMARY In children with inflammatory diseases, the documented elevated fracture risk and bone structural abnormalities highlight the need for additional research to better define methods for the assessment and prevention of bone fragility.
THE DEVELOPMENT AND APPLICATION OF A REFINED METHOD FOR ESTIMATING GENE FLOW FROM ANGIOSPERM PATERNITY ANALYSIS.

While gene flow is an important factor determining the genetic structure of populations, there are few studies that quantify it empirically. Paternity-exclusion analysis has recently been employed to assess the number of seeds fathered by individuals from outside of a study population (gene flow by pollen), but appropriate estimation procedures have been limited to special cases. In this report, we illustrate a general Monte Carlo method that provides an approximate maximum-likelihood estimate of gene flow by pollen from paternity-exclusion analysis. We also show that the method can be used to estimate the number of foreign gametes received by individuals in the study population. Using these methods, we estimated that 7% and 6.3% of the seeds assayed from two wild radish populations were fathered by foreign pollen (95% confidence intervals = 5.0-9.0% and 5.4-7.2%, respectively). Each population was isolated from other radish populations by at least 150 m. Estimates of the number of foreign gametes received by individuals in a population were not correlated with selected reproductive or genetic characters, which included total flower production, total fruit production, seeds per fruit, flower color, floral phenology, and number of heterozygous marker loci.
INTERETHNIC MINORITY CONFLICT IN URBAN AMERICA: THE EFFECTS OF ECONOMIC AND SOCIAL DISLOCATIONS

This paper draws attention to a newly emerging type of intergroup conflict occurring among members of nonwhite ethnic minority groups (i.e., blacks, Hispanics, and Asians) in U.S. cities. Case-stud...
Insulin is Differentially Related to Cognitive Decline and Atrophy in Alzheimer’s Disease and Aging

Abstract We assessed the relationship of insulin resistance with cognitive decline and brain atrophy over two years in early Alzheimer's disease (AD, n = 48) and nondemented controls (n = 61). Intravenous glucose tolerance tests were conducted at baseline to determine insulin area-under-the-curve (AUC). A standard battery of cognitive tasks and MRI were conducted at baseline and 2-year follow-up. In nondemented controls, higher baseline insulin AUC was associated with 2-year decline in global cognitive performance (beta = − 0.36, p = 0.005). In early AD, however, higher insulin AUC was associated with less decline in global cognitive performance (beta = 0.26, p = 0.06), slower global brain atrophy (beta = 0.40, p = 0.01) and less regional atrophy in the bilateral hippocampi and cingulate cortices. While insulin resistance is associated with cognitive decline in nondemented aging, higher peripheral insulin may have AD-specific benefits or insulin signaling may be affected by systemic physiologic changes associated with AD. This article is part of a Special Issue entitled: Imaging Brain Aging and Neurodegenerative disease.
Viscosity changes during isothermal and adiabatic urethane network polymerization

Viscosity was measured as a function of time for the polymerization of a reaction injection molding (RIM) type urethane system: 4,4′-diphenyl methane diisocyanate (MDI) with a polyester triol and dibutyl tin dilaurate catalyst. Viscosity was found to be independent of shear rate. Isothermal viscosity rise was related to extent of reaction and to Mw, by branching theory. Isothermal results at several temperatures were able to predict viscosity rise under adiabatic conditions. The gel point test commonly used to evaluate RIM systems is shown to be essentially an adiabatic test.
The impact of heating, lighting and people in re-using historical buildings: a case study

The impact of lighting, heating and people in re-using historical buildings are discussed for the case study concerning the ceremony room (i.e. the Giant Hall) of a mediaeval palace in Padova. The Hall has substantially four major problems for conservation: (i) the impact of heating, lighting and people when the room is used; (ii) many cracks on the oak panels of the coffered ceiling; (iii) the soiling by dust and soot particles deposited on the frescoes; (iv) the stained glass windows. A microclimate study was performed to know the impact of the environmental variables, and the use of the room, on the artworks preserved inside. The study has proved the impact of the lamps (both incandescence and compact fluorescent lamps) on the ceiling, the penetration of external air in the room, the heat and the moisture released by people, the impact of sunshine through windows and the scatter diagram of the daily cycles in temperature (T) and relative humidity (RH). During winter concerts, the strips of lead which are wrapped round the edge of the cut glass pieces in stained glass windows easily drop below the dew point and form condensation, starting corrosion. A discussion concerns the allowed variability, which should not exceed risk thresholds. A safe interval can be established within the area determined by the most frequent T and RH natural cycles. In fact, both of the cycles were compatible with the artefacts, or the artefacts were already damaged to allow the exceeding dimensional changes. Attention should be paid in the variability external to this area, especially approaching or exceeding a limit equal to twice the mode of the natural variability.
Epipaleolithic and Mesolithic adaptations in Cantabrian Spain and Pyrenean France

The period of deglaciation from ca. 13,000 to ca. 9000 B.P. along the northern edge of the Cantabrian Cordillera and Pyrenees was characterized by marked climatic and environmental oscillations, culminating in the establishment of interglacial conditions. While along the Cantabrian coast, late Upper Paleolithic groups had long been developing diversified systems of adaptation, fully exploiting the wide range of food resources of that narrow but ecologically varied region (notably red deer and marine mollusks), Magdalenian hunters along the southern edge of the Aquitaine basin were becoming increasingly specialized in the hunting of one medium-size game species, reindeer. Thus, while the artifact industries and artistic traditions of the two adjacent regions along the forty-third parallel developed along similar lines in the Magdalenian and Azilian, and despite a common montane specialization in ibex hunting, the changes that came with the end of the Last Glacial affected the human groups of the two regions very differently, as reflected in the early Mesolithic records of Vasco-Cantabria and Gascony, respectively.
Further developments of a damage theory for filled polymers

This paper investigates matrix debonding from filler particles as a mechanism for weakening of a filled polymer. We analyze several simplified models of debonding. Our main concern is its effect on the overall elastic instants; for each debonding model, we calculate the change ΔW in overall strain energy density due to debonding. The resulting formulas for ΔW are all special cases of one general expression. Accordingly, we propose that this expression describes a broad class of debonding models, including some for which a detailed stress and strain analysis is not possible.
Bronchoscopy in patients with haemoptysis and normal chest roentgenograms

Abstract We reviewed the records of 58 patients with haemoptysis and normal chest roentgenograms who underwent fibreoptic bronchoscopy. A diagnosis of malignancy was made in six patients at bronchoscopy. Three patients had bronchogenic squamous cell carcinoma, one a carcinoid tumour and two laryngeal carcinoma. Sputum for cytology was negative for malignant cells in all six patients. Follow-up data were available for the other 52 patients for an average period of 55.7±29.6 ( sd ) months. Two patients had a subsequent diagnosis of bronchogenic carcinoma at 2 and 6 years after initial evaluation. Three patients died from conditions not related to pulmonary malignancy and the remaining patients followed a benign course. Our patients come from a predominately male, elderly population of cigarette smokers. Among such patients, we conclude that bronchoscopy is indicated in the evaluation of those with haemoptysis and a normal chest roentgenogram.
Radiographic diagnosis oftemporomandibular disorders

Although many of the disorders involving the temporomandibular joint and associated structures can be diagnosed clinically on the basis of the history and physical findings, there are others that require the use of various imaging techniques to make an accurate diagnosis or to determine the extent of involvement. To take maximum advantage of the benefits of these procedures, however, it is not only important for the clinician to be able to select the correct methods, but also to understand their limitations as well as their capabilities. In this article the various techniques used for imaging the hard and soft tissues of the temporomandibular joint are reviewed and recommendations are made regarding their appropriate applications. This is a US government work. There are no restrictions on its use.
Consumption, supply and transport: self-organization without direct communication

Swimming bacteria of the species Bacillus subtilis require and consume oxygen. In static liquid cultures the cells' swimming behaviour leads them to accumulate up oxygen concentration gradients generated by consumption and supply. Since the density of bacterial cells exceeds that of the fluid in which they live, fluid regions where cells have accumulated are denser than depleted regions. These density variations cause convection. The fluid motion is dynamically maintained by the swimming of the cells toward regions of attraction: the air-fluid interface and the fluctuating advecting attractors, gradients of oxygen concentration that are embedded in the convecting fluid. Because of the fluid dynamical conservation laws, these complex physical and biological factors generate patterns ordered over distances > 10000 bacterial cell diameters. The convection enhances long-range transport and mixing of oxygen, cells and extracellular products by orders of magnitude. Thus, through the interplay of physical and biological factors, a population of undifferentiated selfish cells creates functional dynamic patterns. Populations of bacteria that have organised themselves into regularly patterned regions of vigorous convection and varying cell concentration interact with their environment as if they were one purposeful, coherent multicellular individual. The mathematical and experimental ingredients of these remarkable phenomena are presented here.
Tetrahedral calcite crystals facilitate self-assembly at the air-water interface.

Calcite crystals often nucleate and grow in solutions of calcium carbonate, and these crystallites can become trapped at the air water interface, where they form unusual structures. The most common is a fractal structure, which can extend over a large fraction of the interface, and whose origin is understood in terms of the aggregation of the particles. Much more rarely, a different and entirely unexpected structure is observed: the particles remain well separated on the interface, forming an ordered phase reminiscent of a two-dimensional colloidal crystal. The structure of the crystallites that form this ordered phase is always observed to be tetrahedral, in contrast to the much more common rhombohedral structure of the crystallites that form the fractal phase. We show that the interparticle interaction potential that leads to this ordered phase is a balance between a long-range attractive interaction and a long-range repulsive interaction. The attraction results from gravity-induced capillary forces, while the repulsion results from a dipole-dipole interaction due to the charged surface of the tetrahedral crystals. The interaction potential is estimated from the thermal motion of the particles, and fits to the theoretically expected values suggest that the effective surface charge on the tetrahedral crystals is $\ensuremath{\sigma}\ensuremath{\sim}0.01\phantom{\rule{0.3em}{0ex}}\text{charges}∕{\mathrm{nm}}^{2}$.
Including Service Learning in the Undergraduate Communication Sciences and Disorders Curriculum: Benefits, Challenges, and Strategies for Success

Purpose To describe some of the benefits of service learning (SL), considerations in course development and construction, and implementation and outcomes of an SL course in the undergraduate communication sciences and disorders (CSD) program at a small, public university in northwest Washington. Method A review of the literature on SL and a description of the author’s experience in course development are provided on the basis of a computerized database search, library search, and discussions with the Western Washington University Center for Service Learning. Conclusions Teaching an SL course can present challenges to both faculty and students; nonetheless, incorporating SL into the undergraduate CSD curriculum is an excellent way of enriching the academic experience and improving critical-thinking skills of young students. SL provides hands-on opportunities for students to apply what they are learning in their CSD classes to real-world contexts, gain a better understanding of course content through engage...
Identity theft complaints: exploring the state‐level correlates

Purpose – Identity theft is an emerging form of criminal behavior, with complaints about the behavior rising. However, little research has explored the correlates of these complaints, especially state‐level correlates. The purpose of this paper is to examine the state‐level characteristics correlated with identity theft complaints.Design/methodology/approach – The present study uses data collected from the 2000 US census and the Federal Trade Commission's 2002 through 2005 reports on identity theft. Regression is used to determine explain identity theft complaints through state‐level characteristics from social disorganization to routine activities theory.Findings – The results indicate that states with more males, higher residential mobility, and more entertainment establishments are likely to have more identity theft complaints. States with more populations that are age 15 and below are less likely to have as many identity theft complaints.Research limitations/implications – The present study only exami...
Study of the retention mechanism for basic compounds on silica under “pseudo-reversed-phase” conditions

Abstract The performance characteristics of a set of nitogenous bases were studied on a number of silicas using aqueous organic mobile phases. The retention characteristics were complex functions of the organic solvent and buffer concentrations as well as pH. The retention mechanisms were shown to be a combination of ion-exchange and interaction with siloxane and silanol groups over the entire range of concentration of organic solvent. The differences in retention on silica were due largely to the differences in ion-exchange strength of the silanol groups and the surface concentration of the siloxane bridges. The same solutes were studied on a range of C8-bonded phases of varying surface coverage, where the same interactions were observed as seen on silica with the addition of reversed-phase interactions. The unexpected relation between capacity factor and bonded-phase coverage was explained by interactions of the several retention mechanisms involved. The retention of small proteins on pure silica was also related to its ion-exchange strength. The performance of the silicas was related to that of the bonded-phase packings prepared from them, the retention of the proteins again being related to the ion-exchange characteristics.
Selective Impairment of Response to Acetylcholine After Ischemia/Reperfusion in Mice

Background and Purpose We previously reported that the endothelium-dependent dilation of pial arterioles by either topical acetylcholine (ACh) or bradykinin (BK) was markedly inhibited after 10 minutes of near total ischemia after bilateral carotid occlusion. The present study tests the responses after 10 minutes of reperfusion and investigates the effect of either oxygen or oxygen radical scavengers on the results. Methods Mice were subjected to bilateral carotid ligation or sham ligation. Pial arteriolar diameters were monitored by an image-splitting technique at a craniotomy site. In separate studies, the responses to topically suffused ACh, BK, or sodium nitroprusside (SNP) were tested before ischemia. After 10 minutes of ischemia and 10 minutes of reperfusion, the response was assessed again. Sham-operated mice were observed in each study. Cerebral blood flow was continuously monitored with a laser-Doppler technique. Additional separate studies were conducted as follows: presence of superoxide dismut...
Effects of Horizontal Tail Ice on Longitudinal Aerodynamic Derivatives

Flight tests were performed with the NASA Lewis Research Center's DH-^6 icing research aircraft to determine the accuracy with which the effects of ice on aircraft longitudinal stability and control could be measured. Flights were made with both a clean (baseline) configuration and with simulated ice on the horizontal tail. At a given trim speed 45 repeat doublet maneuvers were performed in each of four test configurations to determine the ensemble variation of the estimated stability and control derivatives. Additional maneuvers were also performed in each configuration to determine the variation in the longitudinal derivative estimates over a wide range of trim speeds. Stability and control derivatives were estimated by a modified stepwise regression (MSR) technique. A measure of the confidence in the derivative estimates was obtained by comparing the standard error for the ensemble of repeat maneuvers to the average of the estimated standard errors predicted by the MSR program. The magnitude of icing effects on the derivative estimates was strongly dependent on flight speed and aircraft wing flap configuration. With wing flaps up, the estimated derivatives were degraded most at lower speeds corresponding to that configuration. With wing flaps extended to 10 deg, the estimated derivatives were degraded most at the higher corresponding speeds.
The Role of the Contractile Ring during Cytokinesis

Cytokinesis in animals and fungi involves constriction of an actomyosin contractile ring, but the constriction mechanisms and the role of the ring are not established. The constriction rate could be determined only by the properties and internal dynamics of the ring itself (a “dynamically autonomous” mechanism) as suggested by recent experiments on C. elegans embryos. Alternatively, the ring constriction rate could be set by coupled processes that occur simultaneously with constriction (a “dynamically coupled” mechanism). In fission yeast constriction occurs simultaneously with septation, the poorly understood process of cell wall growth in the wake of the constricting ring. To isolate the ring constriction mechanism, we combined mathematical modeling with experiments on fission yeast protoplasts which lack cell wall and adopt a rounded shape. Protoplasts assembled functional contractile rings that constricted without septation by sliding along the plasma membrane without dividing the cell. Because we could manipulate the shapes of protoplast cells, we could test the influence of cell shape on ring constriction dynamics and distinguish between dynamically autonomous and dynamically coupled constriction dynamics. In compressed protoplasts that had a partially flattened shape, contractile rings adopted characteristic bent shapes during constriction that were in remarkably close quantitative and parameter-free agreement with a mathematical model that assumed the ring produces tension but its constriction rate is set by the sliding of ring anchors in the membrane. Thus, ring constriction in fission yeast protoplasts is dynamically coupled: the ring does not set its own constriction rate. Dynamically autonomous models could not reproduce our experimental observations. Our results suggest that in normal yeast cells the constriction rate is determined by the septum growth rate or other coupled process and the role of the ring could be to exert tension on the septum to regulate its growth.
Protease activities in cultured beef lens epithelial cells peak and then decline upon progressive passage

Beef lens cells in culture are readily obtained and provide many opportunities to studyphenomena related to cell differentiation and maturation, environmental stress, disease, and perhaps mechanisms of transformation. Although altered rates of proteolysis are known to accompany these phenomena, the proteolytic activities available in cultured beef lens epithelial cells have not been documented. In this work are documented the specific activities, based on protein and DNA content, ofneutral exo- and endopeptidase, cathepsins B- and D-like enzymes and acid phosphatase in lens epithelial cortical and core tissue and in cultured epithelial cells at passages 1–43. Maximal activity of each protease occurs almost routinely at passage 5 or 9, reaching values of approx. 1400-, 0·77-, 4520-nmol min−1 per mg protein for neutral exopeptidase (passage 5), neutral endopeptidase (passage 5) and cathepsin B (passage 5) respectively, and 7·1 μg trichloroacetic acid soluble peptide min−1 per mg protein for cathepsin D (passage 15). On a μg−1 DNA basis, the maximal specific activities for the same enzymes were 48 (passage 5), 0·03 (passage 5), 283 (passage 9), and 0·5 (passage 9) respectively. In subsequent passages, the specific activities declined to values which were similar to or lower than the specific activities observed for these proteases in lens epithelial tissue.
Design of rural photovoltaic water pumping systems and the potential of manual array tracking for a West-African village

Abstract Photovoltaic (PV) power systems are attractive for use with water pumping systems in remote, off-grid areas with naturally high solar insolation. Two simplified design procedures for these systems are reviewed and compared to a more detailed analysis for a specific village (Ying, 9.7°N, 0.8°W) in West Africa. The simple design methods result in too little flow during months with below-average insolation. A rule-of-thumb chart is presented to predict flow losses for similar installations. To explore possible benefits of tracking strategies, ten different array configurations were simulated: three with fixed orientation, six with single axis tracking, and one with dual axis tracking. Of the three fixed orientation arrays, the configuration to maximize insolation and flow was an equator-pointing array with slope slightly greater than local latitude. The single and dual axis trackers were simulated with seasonal, monthly, and hourly tracking periods, the latter being a good representation of a continuous tracking system. For single axis tracking, a vertical axis array with slope fixed at 30° and variable azimuthal angle provided the best performance. For dual axis tracking, hourly array re-orientation results in significantly more received insolation (17.6% greater than non-tracking horizontal array) while adjustments only on a seasonal or monthly basis still yield 8.5% relative gain. In general, there is little predicted difference between monthly and seasonal re-adjustment of array orientation. A single vertical axis variation allows almost the same benefit as a full two-axis variation if re-oriented on a monthly or seasonal basis. Using one of these strategies could translate into reduced array size, reduced capital costs, or could provide extra margin for future increased water flow requirements due to community growth or unexpected weather. Simple monthly or seasonal adjustment by residents also could increase the sense of ownership in those served by the system.
Hemodynamic consequences of atrial and ventricular pacing in subjects with normal hearts

Abstract The results of atrial and ventricular pacing upon cardiovascular dynamics in 20 subjects with normal cardiovascular systems have been analyzed. The average cardiac index during atrial pacing was 3.17 L./min., M. 2 compared to 2.66 during ventricular pacing. Similar conclusions were possible by analysis of the data at varying heart rates of 60 to 89,90 to 109 and 110 to 140. It is concluded that the atrial contribution to ventricular function is significant even in normal subjects.
Enabling energy efficient reliability in embedded systems through smart cache cleaning

Incessant and rapid technology scaling has brought us to a point where today's, and future transistors are susceptible to transient errors induced by energy carrying particles, called soft errors. Within a processor, the sheer size and nature of data in the caches render it most vulnerable to electrical interference on data stored in the cache. Data in the cache is vulnerable to corruption by soft errors, for the time it remains actively unused in the cache. Write-through and early-write-back [Li et al. 2004] cache configurations reduce the time for vulnerable data in the cache, at the cost of increased memory writes and thereby energy. We propose a smart cache cleaning methodology, that enables copying of only specific vulnerable cache blocks into the memory at chosen times, thereby ensuring data cache protection with minimal memory writes. In this work, we first propose a hybrid (software-hardware) methodology. We then propose an improved software solution that utilizes cache write-back functionality available in commodity processors; thereby reducing the hardware overhead required to implement smart cache cleaning for such systems. The parameters involved in the implementation of our Smart Cache Cleaning (SCC) technique enable a means to provide for customizable energy-efficient soft error reduction in the L1 data cache. Given the system requirements of reliability, power-budget and runtime priority of the application, appropriate parameters of the SCC can be customized to trade-off power consumption and L1 data cache reliability. Our experiments over LINPACK and Livermore benchmarks demonstrate 26p reduced energy-vulnerability product (energy-efficient vulnerability reduction) compared to that of hardware based cache reliability techniques. Our software-only solution achieves same levels of reliability with an additional 28p performance improvement.
On the configuration of a propagating surface fatigue crack

The configuration assumed by a semi-elliptical surface crack as it propagates into a thick plate under fatigue loading is relevant both to fracture testing practice and to fundamental understanding of the fatigue process. It has not been possible to delineate this configuration completely by nondestructive experimental techniques, and therefore an analytical model of the process is essential to its understanding. The present paper proposes such a model and uses previously published experimental data in calculating the changing surface crack configuration in fatigue cycled 4340 steel. The results predict that a surface crack will tend to grow more shallow in relation to its length with increased fatigue cycling.
Ionization balance in inertial confinement fusion hohlraum plasmas

Abstract We present X-ray spectroscopic measurements of the ionization balance in inertial confinement fusion hohlraums supported by 4 ω Thomson scattering diagnostics. The experimental data show agreement with non-LTE radiation-hydrodynamic calculations of the averaged Au charge state and electron temperatures. These findings are consistent with the successful integrated modeling of the hohlraum radiation fields. Comparisons with detailed synthetic spectra calculations show that the experimental ionization distribution is shifted indicating non-steady state kinetics.
Design, synthesis, and photophysical studies of a porphyrin-fullerene dyad with parachute topology; charge recombination in the marcus inverted region

As part of a continuing investigation of the topological control of intramolecular electron transfer (ET) in donor-acceptor systems, a symmetrical parachute-shaped octaethylporphyrin-fullerene dyad has been synthesized. A symmetrical strap, attached to ortho positions of phenyl groups at opposing meso positions of the porphyrin, was linked to [60]-fullerene in the final step of the synthesis. The dyad structures were confirmed by H-1, C-13, and He-3 NMR, and MALDI-TOF mass spectra. The free-base and Zn-containing dyads were subjected to extensive spectroscopic, electrochemical and photophysical studies. UV-vis spectra of the dyads are superimposable on the sum of the spectra of appropriate model systems, indicating that there is no significant ground-state electronic interaction between the component chromophores. Molecular modeling studies reveal that the lowest energy conformation of the dyad is not the C-2v symmetrical structure, but rather one in which the porphyrin moves over to the side of the fullerene sphere, bringing the two pi-systems into close proximity, which enhances van der Waals attractive forces. To account for the NMR data, it is proposed that the dyad is conformationally mobile at room temperature, with the porphyrin swinging back and forth from one side of the fullerene to the other. The extensive fluorescence quenching in both the free base and Zn dyads is associated with an extremely rapid photoinduced electron-transfer process, k(ET) approximate to 10(11) s(-1), generating porphyrin radical cations and C-60 radical anions, detected by transient absorption spectroscopy. Back electron transfer (BET) is slower than charge separation by up to 2 orders of magnitude in these systems. The BET rate is slower in nonpolar than in polar solvents, indicating that BET occurs in the Marcus inverted region, where the rate decreases as the thermodynamic driving force for BET increases. Transient absorption and singlet molecular oxygen sensitization data show that fullerene triplets are formed only with the free base dyad in toluene, where triplet formation from the charge-separated state is competitive with decay to the ground state. The photophysical properties of the P-C-60 dyads with parachute topology are very similar to those of structurally related rigid pi-stacked P-C-60 dyads, with the exception that there is no detectable charge-transfer absorption in the parachute systems, attributed to their conformational flexibility. It is concluded that charge separation in these hybrid systems occurs through space in unsymmetrical conformations, where the center-to-center distance between the component pi-systems is minimized. Analysis of the BET data using Marcus theory gives reorganization energies for these systems between 0.6 and 0.8 eV and electronic coupling matrix elements between 4.8 and 5.6 cm(-1).
Quantitative assessment of mis-registration issues of diffusion tensor imaging (DTI)

Image distortions caused by eddy current and patient motion have been two major sources of the mis-registration issues in diffusion tensor imaging (DTI). Numerous registration methods have been proposed to correct them. However, quality control of DTI remains an important issue, because we rarely report how much mis-registration existed and how well they were corrected. In this paper, we propose a method for quantitative reporting of DTI data quality. This registration method minimizes a cost function based on mean square tensor fitting errors. Registration with twelve-parameter full affine transformation is used. From the registration result, distortion and motion parameters are estimated. Because the translation parameters involve both eddy-current-induced image translation and the patient motion, by analyzing the transformation model, we separate them by removing the contributions that are linearly correlated with diffusion gradients. We define the metrics measuring the amounts of distortion, rotation, translation. We tested our method on a database with 64 subjects and found the statistics of each of metrics. Finally we demonstrate that how these statistics can be used for assessing the data quality quantitatively in several examples.
The development of spatial and temporal contrast sensitivity

This paper reviews work on the development of spatial and temporal contrast sensitivity in human infants. Both electrophysiological and behavioral techniques have been used. Infants' spatial contrast sensitivity functions exhibit a large deficit in spatial resolution and overall contrast sensitivity relative to adult functions. These measurements also reveal continuous development between one and six months of age. Infants' temporal resolution does not exhibit a large deficit relative to adults'. Indeed, critical flicker frequency is essentially adult-like by two months of age. This combination of coarse spatial resolution and fine temporal resolution is analogous to What is observed in the peripheral retina of the adult visual system.
A varactor-tuned patch oscillator for active arrays

The design and construction of a relatively wideband quasi-optical voltage-controlled oscillator (VCO) is described. This VCO uses a varactor-tuned microstrip patch antenna and may be used as an element in quasi-optical power combining oscillator arrays. Measurements of this VCO indicate that over 1.3 GHz of tuning was achieved, with less than /spl plusmn/1.5 dB of amplitude variation over that range. >
Preventing Occupational Exposures to Antineoplastic Drugs in Health Care Settings

The toxicity of antineoplastic drugs has been well known since they were introduced in the 1940s. Because most antineoplastic drugs are nonselective in their mechanism of action, they affect noncancerous as well as cancerous cells, resulting in well-documented side effects. During the 1970s, evidence came to light indicating health care workers may be at risk of harmful effects from antineoplastic drugs as a result of occupational exposure. Since that time, reports from several countries have documented drug contamination of the workplace, identified drugs in the urine of health care workers, and measured genotoxic responses in workers. Evidence also exists of teratogenic and adverse reproductive outcomes and increased cancers in health care workers. During the past 30 years, professional organizations and government agencies have developed guidelines to protect health care workers from adverse effects from occupational exposure to antineoplastic drugs. Although many safety provisions were advanced to reduce worker exposure in the 1980s, recent studies have shown that workers continue to be exposed to these drugs despite safety policy improvements. In 2004, the National Institute for Occupational Safety and Health (NIOSH) published an alert reviewing the most recent information available and promoting a program of safe handling during their use.