cssi/SciSciGPT-SciSciNet huggingface dataset:
Length Scale Dependent Micro-Rheology of Cellularized Type I Collagen Gels

Collagen gels are commonly used as the substrate for experiments on cell mechanics because collagen is the most abundant protein in the extracellular matrix of most animals. The gels are commonly approximated as homogeneous elastic materials; however, on smaller length scales, the inhomogeneity of the collagen fiber network becomes very apparent. During gelation, collagen fibers can group together to form larger fiber bundles, with the size, shape, and distribution of these bundles depending on the collagen concentration and the temperature during gelation. In addition, when cells are embedded in the collagen substrate, the cell adhesion forces deform the collagen and alter its elastic properties. We study local variation in the elastic modulus of type I collagen gels and characterize inhomogeneity caused by cell adhesions and fiber bundles in the collagen network. We expect the cell adhesions and the collagen fiber bundles to each have distinct length scales over which the elastic properties will vary. These length scales will be calculated by separating the gel into domains in which the elastic properties of the collagen change in a characteristic way. We map the local elastic modulus of type I collagen gel using active two-point micro-rheology. Optical tweezers are used to perturb microscopic particles embedded in the gel and in-line holographic particle tracking is used to calculate the particle displacements. The local elastic properties are calculated by cross-correlating the trajectory of the perturbed particle with the trajectories of the surrounding particles. Then confocal reflection microscopy is used to image the collagen fiber network, showing the locations of cells and fiber bundles. These images are used to compare the distribution of cells and fiber bundles to the results of the local micro-rheology calculations.
Systems Approach to Vaginal Delivery of Drugs II: In Situ Vaginal Absorption of Unbranched Aliphatic Alcohols

The absorption of unbranched aliphatic alcohols in the rabbit vagina was studied using a perfusion method, and the absorption rates were found to be first order with respect to the drug concentration in the vagina from methanol to octanol. A physical model involving an aqueous diffusion layer in series with a membrane consisting of aqueous pores and lipoidal pathways was used for analyzing the data. The physically based parameters in the model were determined. An effective diffusion layer thickness (“unstirred layer”) of around 0.035 cm was found. The increase in the permeability coefficient for the lipoidal pathway per methylene group was around 2.5 for this homologous series.
Sizing Subcellular Organelles and Nanoparticles Confined within Aqueous Droplets

This article describes two complementary techniques, single-particle tracking and correlation spectroscopy, for accurately sizing nanoparticles confined within picoliter volume aqueous droplets. Single-particle tracking works well with bright particles that can be continuously illuminated and imaged, and we demonstrated this approach for sizing single fluorescent beads. Fluorescence correlation spectroscopy detects small intensity bursts from particles or molecules diffusing through the confocal probe volume, which works well with dim and rapidly diffusing particles or molecules; we demonstrated FCS for sizing synaptic vesicles confined in aqueous droplets. In combination with recent advances in droplet manipulations and analysis, we anticipate this capability to size single nanoparticles and molecules in free solution will complement existing tools for probing cellular systems, subcellular organelles, and nanoparticles.
Remote detection of ocean waste

An application of characteristic vector analysis to ocean color spectra for the detection of pollutants in water is described. The technique can be useful for detecting and distinguishing among a variety of substances in the water. The analysis also illustrates the variability of the water color spectra with both concentration and depth distribution. Both concentration and depth information may be extractable from passive multispectral data under certain circumstances.
Functional brain networks in Parkinson's disease

With the advent of new methods of network analysis, we have utilized metabolic data acquired through positron emission tomography (PET) to identify disease-related patterns of functional pathology in the movement disorders. In Parkinson's disease (PD), we have used [(18)F]-fluorodeoxyglucose (FDG)/PET to identify a disease-related regional metabolic covariance pattern characterized by lentiform and thalamic hypermetabolism associated with regional metabolic decrements in the lateral premotor cortex, the supplementary motor area, the dorsolateral prefrontal cortex, and the parieto-occipital association regions. The expression of this network is modulated in a predictable fashion by levodopa therapy and by stereotaxic interventions for PD.We have extended this network analytical approach from studies of glucose metabolism in the resting state to dynamic studies of brain activation during motor performance. These PET studies utilized [(15)O]-water (H(2) (15)O) to measure cerebral blood flow activation responses during the execution of simple and complex motor tasks. In addition to the modulation of abnormal resting metabolic networks, effective PD therapy can enhance brain activation responses during motor execution, with specific regional associations with improvements in timing and spatial accuracy.This approach is also useful in identifying specific brain networks mediating the learning of sequential information. We have found that the normal relationship between brain networks and learning performance are altered in the earliest stages of PD with a functional shift from striatal to cortical processing. Brain activation PET studies during therapeutic interventions for PD demonstrate how normal brain-behavior relationships can be restored with successful therapy. Thus, functional brain imaging with network analysis can provide insights into the mechanistic basis of basal ganglia disorders and their treatment.
Performance of silicon drift detectors in a magnetic field

Abstract A study of the properties of silicon drift detectors in a magnetic field was carried out. A silicon drift detector with 41 anodes, providing unambiguous x and y position information, was used for measurements. Studies were done in three principal orientations of the detector relative to the direction of the magnetic field. The magnetic field was varied between 0 and 0.7 T and the drift field between 300 and 600 V/cm. Basic agreement with the theory of electron transport in semiconductors in a magnetic field was found. The transport properties of electrons in a magnetic field can be described by a mobility matrix. The components of the matrix depend on the electron mobility, Hall mobility and on the vector of the magnetic field. The precision of measurement was better than 0.2% for most of the parameters. For the electric field of a silicon drift detector, there is a first-order effect of the magnetic field only in one out of three principal directions. In this direction, the plane of the detector is perpendicular to the magnetic field and electrons drift at an angle α relative to the direction of the drift field. In two other principal directions, which are more important for tracking of the particles with drift detectors, there are no first-order magnetic effects.
Detrapping from magnetic field errors as a random walk ESCAPE

Abstract We examine the effects of random magmetic field errors on the performance of a free electron laser. We report a modification of the straightest wiggler orbit operating point (SWOOP) theory for two very high efficiency systems. The first system utilizes a gapless pulsed cryogenic wiggler and the second a continuous wave gapless superconduction wiggler. We further show a method to improve the choice of separation of correctors. To establish this method we show that corrected steering errors, BPM errors and gap misadjustments are errors similarly construed as phase errors (ESCAPE). The corrected steering errors also have a component that requires retuning of the wiggler and this task is relegated to unoptimized SWOOP. Without this retuning, these errors are emittance cannot be removed by returning except for the resonant particle. The remaining part of the field errors are similar to similar to an effective emittance, but because the steering errors are homogeneous and the emittance is inhomogeneous, the phase errors and behave like a random force in the KMR potential. In a returned wiggler, the effective energy broadening from emittance is responsible for the initial trapping and the field errors are responsible for the detrapping. This work constitutes a complete high-efficiency model of phase, gap and corrected steering errors for an enmsemble of the free electron lasers. The classical bound-free transition, the detrapping phenomenon, is treated as the Kramers problem.
What do hands know about hills? Interpreting Taylor-Covill and Eves (2013) in context.

Hills appear much steeper than they are. Although near surface slant is also exaggerated, near surfaces appear much shallower than equivalently slanted hills. Taylor-Covill and Eves (2013) propose a new type of palm orientation measuring device that provides outputs that accurately reflect the physical slants of stairs and hills from 19 to 30° and also seems to accurately reflect the slants of near surfaces (25–30°). They question the validity of the observations of Durgin, Hajnal, Li, Tonge & Stigliani (2010), who observed that palm boards grossly underestimated near surfaces. Here I review our recent work on the visual and haptic perception of near surface orientation in order to place Taylor-Covill and Eves' arguments in context. I note in particular that free hand measures of real surfaces in near space show excellent calibration, but free hand measures show gross exaggeration for hills. This leads to the question of the grounds for preferring a mechanical device to a freely wielded hand. In addition I report an investigative replication of the crucial observations that led to our concerns about the value of palm boards as measures of perception and note the specific methodological details that we have accounted for in our procedures. Finally, I propose some testable hypotheses regarding how better-than-expected haptic matches to hills may arise.
Chemical approaches to the mode of action of carboxypeptidase A

Our studies of the mechanism of action of carboxypeptidase A have been guided by the dual specificity of this enzyme as altered either by replacement of the native zinc atom at the active site with other metal ions or by chemical modification of amino acid side chains. In almost all instances esterase activity toward HPLA increased and peptidase activity toward CGP decreased in response to such treatments. A mechanism postulating the modification of a single catalytically active amino acid residue was designed as the simplest chemical event that could provide a unified account for such similar functional consequences in response to a variety of agents (Vallee, Riordan & Coleman 1963). The mechanism was postulated before the identification of the residues affected by chemical modifications. Similarly, the number and nature of binding groups were unknown, and thus, could not be considered. It was recognized that the scheme would have to be amplified, once specific residues were identified. Significant progress, in this regard, has occurred over the past several years and this report summarizes the present status of our understanding.
Social information: the person is the message.

Abstract Assumptions that Shannon's concepts cannot extend to social systems are challenged by showing that social information measures the reduced uncertainties individuals have about the systemic effects of each other's behavior. The `meaning' of individual actions is their collective consequences, which also measure reductions in systemic uncertainties about collective environments. Meaning is communicated through messages using media such as values, ethics and morals, which encourage individuals to act predictably and replicate the improbable behaviors characterizing particular societies. When individuals internalize meaning, their personal identities communicate societal priorities to future generations.
A course assessment process for curricular quality improvement.

Objective. To describe a systematic assessment process that provides continuous improvement in the curriculum, supports faculty development, and enhances student learning outcomes. Design. Teams of faculty members, students, and course instructors conducted course assessments, which consisted of monitoring the delivered instruction for agreement with planned content and course integration within the curriculum, and providing ongoing feedback for improving course content, course management, faculty teaching, and student learning experiences. Assessment. Areas needing improvement were identified and appropriate changes were made. Improvements were achieved in course policy standardization, course integration within the curriculum, faculty teaching behaviors, and student experiences. Conclusion. The curriculum assessment plan provides a structured method of monitoring and delivering continuous quality improvement.
Numerical computation of equilibrium bid functions in a first-price auction with heterogeneous risk attitudes

We use numerical methods to compute Nash equilibrium (NE) bid functions for four agents bidding in a first-price auction. Each bidderi is randomly assigned:r i ∈ [0,r max], where 1 −r i is the Arrow-Pratt measure of constant relative risk aversion. Eachr i is independently drawn from the cumulative distribution function Ф(·), a beta distribution on [0,r max]. For various values of the maximum propensity to seek risk,r max, the expected value of any bidder's risk characteristic,E (r i ), and the probability that any bidder is risk seeking,P (r i > 1), we determine the nonlinear characteristics of the (NE) bid functions.
Scenario relaxation algorithm for finite scenario-based min-max regret and min-max relative regret robust optimization

Most practical decision-making problems are compounded in difficulty by the degree of uncertainty and ambiguity surrounding the key model parameters. Decision makers may be confronted with problems in which no sufficient historical information is available to make estimates of the probability distributions for uncertain parameter values. In these situations, decision makers are not able to search for the long-term decision setting with the best long-run average performance. Instead, decision makers are searching for the robust long-term decision setting that performs relatively well across all possible realizations of uncertainty without attempting to assign an assumed probability distribution to any ambiguous parameter. In this paper, we propose an iterative algorithm for solving min-max regret and min-max relative regret robust optimization problems for two-stage decision-making under uncertainty (ambiguity) where the structure of the first-stage problem is a mixed integer (binary) linear programming model and the structure of the second-stage problem is a linear programming model. The algorithm guarantees termination at an optimal robust solution, if one exists. A number of applications of the proposed algorithm are demonstrated. All results illustrate good performance of the proposed algorithm.
Thermodynamics of solution of cyclic alkanes from C5 through C11 in n-C36H74 at 373.15 K using gas-liquid chromatography

Abstract Enthalpies and entropies of solution from the 1 atm vapor state to the infinitely dilute solution in n-C36H74 at 373.15 K have been measured for cyclic alkane solutes containing 5 through 11 carbon atoms. Enthalpies of solution are more negative than those exhibited by corresponding normal alkanes by about 0.5 kcalth mol−1. The difference is attributed to the considerably smaller molar volumes of the cyclic alkanes, requiring less energy input upon solution. While the entropies of solution of n-pentane and cyclopentane are very nearly the same, the cyclic alkanes display increasingly less negative values relative to the n-alkanes as the number of carbon atoms in the solute is increased, resulting in much lower equilibrium partial pressures for the cyclic molecules. The observed entropies of solution are predicted by a simple equation based on volume fraction. It appears that for normal and cyclic alkanes, molar volume is the most important variable in determining solution properties at infinite dilution.
The Use of “Solutions” for Problem Identification

This paper describes a method which can be used to identify internal organizational type problems. The systems approach is assumed, necessitating a process designed to identify as many problem areas as possible before solutions are formulated. The argument presented here is that a solutions orientation is more natural than a systems orientation, such that people find it much easier to suggest solutions than to identify problems. Thus the task of the problem identifier is to collect the solutions offered and attempt to derive from the solutions a statement of the problem being addressed. In doing this it becomes necessary to have a problem area classification scheme as an aid. Such a scheme is presented as derived from an actual example; however, this scheme is not proported to be universally applicable. The process is quick, straightforward and the results should be of value to many organizations.
Titanium and Zirconium Complexes That Contain the Tridentate Diamido Ligands [(i-PrN-o-C6H4)2O]2- ([i-PrNON]2-) and [(C6H11N-o-C6H4)2O]2- ([CyNON]2-)

A variety of five- and six-coordinate titanium and zirconium dialkyl complexes that contain the [(i-PrN-o-C6H4)2O]2- ([i-PrNON]2-) ligand have been prepared, among them [i-PrNON]Ti(CH2CHMe2)2, [i-PrNON]Ti(CH2CMe3)2, [i-PrNON]Zr(CH2CH3)2, and [i-PrNON]Zr(CH2CHMe2)2. These species serve as sources of complexes such as {[i-PrNON]Ti(PMe3)2}2(μ-N2), [i-PrNON]Ti(CHCMe3)(PMe3)2, [i-PrNON]Zr(CH2CHMe2)2(PMe3), and [i-PrNON]Zr(H2CCMe2)(PMe3)2. The reaction between [i-PrNON]Ti(CH2CMe3)2 and Me2PCH2CH2PMe2 in the absence of dinitrogen yields (i-PrNC6H4)(i-PrNC6H4O)Ti(dmpe), a pseudooctahedral species in which one aryl−oxygen bond has been cleaved. In all structurally characterized complexes in which the [i-PrNON]2- ligand is intact, it adopts a mer configuration in which the donor oxygen atom is planar. Analogous dialkyl complexes [CyNON]MR2 (Cy = cyclohexyl; M = Zr, R = Me, Et, i-Bu, CH2CMe3, allyl; M = Ti, R = Me, CH2CMe3, i-Bu) have also been prepared. Decomposition of [i-PrNON]Zr(CH2CH3)2 in the absence of phosph...
Short-term Versus Continuous Chisel and No-till Effects on Soil Carbon and Nitrogen

For various reasons, North American crop farmers are more likely to practice limited-duration no-till than continuous no-till (NT). Little is known about effects of short-term no-till (ST-NT) on organic C and total N relative to NT and conventional-till systems. A field experiment was initiated in 1980 to study the effects of NT, chisel plow (CP), and moldboard plow in continuous corn (CC; Zea mays L.) and soybean (Glycine max. L.)-corn (SC) rotations on dark prairie soil. In 1996, the moldboard treatments were split into a ST-NT subplot and an intermittently chisel-plowed (STI-CP) subplot that was chiseled only before corn. In 2003, soil samples were taken incrementally to the 1.0-m depth from NT, CP, ST-NT, and STI-CP plots. Soil C and N accumulation was unaffected by rotation system at any depth interval. Tillage treatments significantly affected soil C and N concentrations only in the upper 50 cm. On an equivalent soil mass basis, C storage to 1.0 m after 24 yr totaled 151 Mg ha -1 in continuous NT, but just 108 Mg ha -1 in continuous CP. Short-term no-till and STI-CP systems resulted in 26 and 21 Mg ha -1 , respectively, more soil C than CP. Total N storage was similar for NT and ST-NT systems, but was significantly lower (4 Mg ha -1 less) with CP. Our results suggest that the combination of moldboard plowing (17 yr) followed by short-term (6-7 yr) no-till or intermittent chisel was generally superior to continuous chisel plowing (24 yr) in soil C and N contents.
Changes in insulin-like growth factor-I (IGF-I), IGF-binding protein-3, growth hormone (GH)-binding protein, erythrocyte IGF-I receptors, and growth rate during GH treatment.

To assess the relative determinants of growth rate, we measured serum levels of insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP-3), and GH-binding protein (GHBP) as well as IGF-I erythrocyte receptor specific binding (SB) in 14 prepubertal GH-deficient children before and during the first year of treatment with 0.043 mg/kg.day GH. Serum IGF-I and IGFBP-3 levels, measured by RIA, were significantly increased by 2 weeks and showed progressive increases throughout the year of GH therapy. Growth rate (height velocity SD score adjusted for bone age) correlated best with the 12 month changes in IGFBP-3 (r = 0.81; P < 0.001) and IGF-I (r = 0.72; P = 0.005), and to a lesser extent with the 12 month absolute IGFBP-3 (r = 0.58; P = 0.04) and the 6 month change in IGFBP-3 (r = 0.55; P = 0.05). The baseline IGF-I correlated inversely with the growth rate during GH therapy (r = -0.55; P = 0.05) and was the best pretreatment predictor of growth response. GHBP, as measured by ligand-mediated immunofun...
Cell Death by Glutamine Repeats

A number of eukaryotic proteins contain stretches of repeating glutamine residues ( 1 ). For example, huntingtin pro- tein contains a glutamine-repeat sequence of 6 to 35 residues, and prion protein has a domain rich in glutamine and asparagine residues (Q/N-rich domain). Expansion of the glutamine repeat in huntingtin and at least seven other proteins results in neurodegenerative disease ( 2 ), whereas conformational changes in prion protein cause a range of spongiform encephalopathies ( 3 ). Glutamine repeats and Q/N-rich domains can form α-helical and coiled-coil secondary structures, driving protein aggregation. Aggregation of numerous disease-associated proteins that do not contain polyglutamine domains has been associated with neurodegeneration (such as the β-amyloid peptide and the tau protein in Alzheimer's disease). Thus, the presence of glutamine-rich domains in proteins associated with neurodegeneration could be due to their ability to induce protein aggregation per se. Alternatively, glutaminerich proteins could have a “natural role” in inducing cell death that becomes dysregulated in neurodegenerative disease. On page 970 of this issue, Blum et al. ( 4 ) identify a Q/N-rich protein that aids in the programmed cell death of a specific cell in the model nematode Caenorhabditis elegans . This result provides support for the “natural role” explanation for the association of glutamine-rich proteins and neurodegeneration.
THE SEXUAL CYCLE OF NETRIUM DIGITUS

A B S T R A C T The life cycle of 2 varieties of Netrium digitus, a saccoderm desmid, was studied in pure culture on mineral media. Netriumn digitus var. digitus from Indiana is homothallic, and Netrium digitus var. lamellosum from Minnesota is heterothallic. Previous observations by other investigators on the events of the sexual cycle are confirmed and extended. Zygospores of both varieties are formed in the conjugation tube. Fusion of gametic nuclei occurs after the dormant period of zygospores, and meiosis occurs at the time of germination. Conjugation is induced in a reliable manner in both varieties by omitting nitrogen from the medium and by exposing the cultures to the proper conditions of light and temperature. The relationship between photoperiod, nitrogen depletion, and induction of conjugation is discussed. KNOWLEDGE of the morphology and sexual cycles of saccoderm desmids (family Alesotaeniaceae) has been based, for the most part, on observations of natural collections. These studies lacked the reliability and completeness now possible through pure culture techniques. The isolation into culture of sexual Netrium strains provides an opportunity for studying the conditions under which various stages of the sexual cycle are induced and for extending existing knowledge of the structures and events in the cycle. The genus Netrium was originally described as a subgenus of Closterium Nitzsch by Nageli (1849).
Bahiagrass response to applied nitrogen and harvest interval

Abstract A growth model has been developed for warm‐season perennial grasses which relates seasonal distribution of dry matter to calendar time through the probability equation, and which relates total seasonal dry matter to harvest interval through a linear‐exponential equation. The model is used to describe response of ‘Tifton‐9’ bahiagrass (Paspalum notatum Flogge) to time and harvest interval at Quincy, FL. It is also shown that yield response to applied nitrogen (N) is described by the logistic equation, in agreement with earlier results for bahiagrass and other forage grasses. This model removes the restriction of harvest interval to 6 or 7 wk of the previous linear growth model. Maximum dry matter yield exceeded 20 Mg ha‐1. Maximum incremental dry matter response to applied N occurred at approximately 140 kg N ha‐1. A harvest interval of 8 wk provided peak dry matter production. The mean and standard deviation of dry matter distribution were 28.5 wk and 6.0 wk, respectively. Correlation coefficient...
Service orientation of restaurant employees

Abstract The purpose of this study was to identify and investigate factors that might influence restaurant employees' degree of service orientation. Service orientation has been characterized as the disposition of employees to be helpful, thoughful, considerate, and co-operative towards customers. This study, exploratory in nature, examined service orientation of employees and managers working in pizza restaurants. Results suggest that service orientation is comprised of three components: organizational support, customer focus, and service under pressure. Results also suggest that increasing employees' job involvement, job satisfaction, and job security could assist in improving their overall service orientation.
Preeclampsia: Is induction of labor more successful?

Objective To test the hypothesis that preeclamptic women are more readily inducible than are nonpreeclamptic women, regardless of cervical condition. Methods One hundred eighty-three preeclamptic women and 461 nonpreeclamptic women requiring labor induction were studied prospectively. Patients were categorized by Bishop score, parity, gestational age, and method of induction. Outcome variables were success of induction and cesarean delivery rates. Results Failed induction was significantly more common in the preeclamptic group (8.2% versus 1.7%; odds ratio [OR] 5.06; 95% confidence interval [CI] 1.97,13.28), as was cesarean delivery (28% versus 16%; OR 2.09; 95% CI 1.36, 3.18). When controlled by logistic regression for Bishop score, parity, method of induction, epidural anesthesia, macrosomia, and gestational age, a fourfold higher risk of failed induction and a twofold higher risk of cesarean delivery were found in the preeclamptic group. Conclusions Induction of labor in preeclamptic women has a higher risk of failure and consequently of cesarean delivery than in nonpreeclamptic women. The vast majority of patients achieve vaginal delivery.
Continuous fermentation of cellulosic biomass to ethanol

Experimental results are presented for continuous conversion of pretreated hardwood flour to ethanol. A simultaneous saccharification and fermentation (SSF) system comprised ofTrichoderma reesei cellulase supplemented with additional β-glucosidase and fermentation bySaccharomyces cerevisiae was used for most experiments, with data also presented for a direct microbial conversion (DMC) system comprised ofClostridium thermocellum. Using a batch SSF system, dilute acid pretreatment of mixed hardwood at short residence time(10 s, 220°C, 1% H2SO4) was compared to poplar wood pretreated at longer residence time (20 min, 160°C, 0.45% H2SO4). The short residence time pretreatment resulted in a somewhat (10–20%) more reactive substrate, with the reactivity difference particularly notable at low enzyme loadings and/or low agitation. Based on a preliminary screening, inhibition of SSF by byproducts of short residence time pretreatment was measurable, but minor. Both SSF and DMC were carried out successfully in well-mixed continuous systems, with steady-state data obtained at residence times of 0.58–3 d for SSF as well as 0.5 and 0.75 d for DMC. The SSF system achieved substrate conversions varying from 31% at a 0.58-d residence time to 86% at a 2-d residence time. At comparable substrate concentrations (4–5 g/l) and residence times (0.5–0.58 d), substrate conversion in the DMC system (77%) was significantly higher than that in the SSF system (31%). Our results suggest that the substrate conversion in SSF carried out in CSTR is relatively insensitive to enzyme loading in the range 7–25 U/g cellulose and to substrate concentration in the range of 5–60 g/L cellulose in the feed.
Calcium phosphate cements for lost circulation control in geothermal drilling

Abstract Calcium phosphate cements were investigated as potential lost circulation control materials for geothermal wells. The calcium phosphate cements were produced by reacting calcium aluminate (high alumina) cement with sodium phosphate compounds. Pumpable formulations with thickening times of up to 2 h at temperatures between 25 and 90°C were developed and characterized. The materials showed rapid set behavior, early strength development, low permeability and acceptable durability in hydrothermal environments. Strengths up to 4 MPa were achieved 4 h after mixing and permeabilities were of the order of 10 −9 –10 −7 cm/s at 24 h. Partial replacement of calcium aluminate cement with ground granulated blast furnace slag was found to reduce the amount of borax retarder required to maintain pumpability at elevated temperatures and pressures.
Generation Of White Light At 1 Khz

We have developed a new dye laser and c.w.-pumped regenerative amplifier system capable of generating white light continuum at a repetition rate higher than 1 KHz.
Rapid Weight Gain During the First Year of Life Predicts Obesity in 2–3 Year Olds from a Low-income, Minority Population

As the prevalence of childhood obesity increases, researchers continue to attempt to identify factors contributing to obesity. The purpose of this study was to define the relationship between birth weight, rapid weight gain (RWG), and early childhood obesity in a low-income, inner-city minority population. In this retrospective chart review, researchers documented every medical encounter recorded in the chart from birth to 3 years for 203 3 year old minority children from low-income families living in an urban area. Based on Center for Disease Control and Prevention’s growth charts and tables, z-scores at birth, 4 months, and 1 year were calculated and RWG determined. Researchers determined Body Mass Index percentiles at 3 years of age using the last available weight and height between 24 and 38 months of age. Eight percent of children were underweight, 62% were normal weight, 12% were at overweight and 18% were obese. Children who experienced RWG during the first year of life were 9.24 (CI: 3.73–22.91) as likely to become obese as those who did not experience RWG. Neither low birth weight nor being male increased the odds of becoming obese. Low birth weight predicted underweight at 24–38 months. In this high-risk population, children experiencing RWG during the first year of life have a significantly increased risk of being obese during the preschool years. Future research should identify factors leading to RWG, including specific infant feeding practices.
Prevalence of State Firearm Mortality and Mental Health Care Resources

A disproportionate share of firearm suicides and homicides are committed by individuals who have a psychiatric diagnosis, many with a history of substance abuse. This study assessed whether selected variables that potentially indicate increased access to mental health care or known demographic risk factors for firearm trauma best predicted state variations in firearm homicide and suicide. Partial correlation coefficients indicated that the proportion of the population within a given state that was African American or Hispanic was significantly associated with increased state firearm homicides. The percent of the population within a given state that had earned a Baccalaureate degree was associated with decreased state firearm homicides. Additionally, increased state firearm ownership rates were significantly associated with firearm suicides, while state educational expenditures were associated with a significant reduction in firearm suicides. The findings suggest that mental health resources within a state have minimal association with firearm homicide and suicide rates. However, state levels of educational achievement and educational expenditures reduce firearm mortality.
Linear signal decomposition approach to affine-invariant contour identification

A means for the identification of objects from contours despite affine transform induced distortions that takes the form of a linear signal space decomposition has been obtained. This new technique also yields robust estimates of the affine transformation from which the 3-D rotations of a near planar object may be obtained. The ability to determine object identity and orientation from a singe model representation without iteration or combinatorial search proceeds from the use of affine invariant differential measures that may be derived via Lie group theory. The resulting technique is extremely robust in the presence of noise (or nonplanarity of the object) owing to the error rejection properties of the signal space projection operations. The resulting algorithm is amenable to high-speed implementation with digital signal processing hardware architectures because it can be reduced to a sequence of linear 1-D signal processing operations. Included in this paper are a number of demonstration results that illustrate the resilience of the solutions in the presence of severe nonaffine distortion and pixelization error.
On Searching for Large Objects with Small Probes: A Search Model for Exploration

We propose a model for optimal allocation of effort when searching for large objects with small probes. Because of the size of the objects, search activities at different locations can be physically and statistically dependent, and consequently classical search models are inappropriate. The difficulties resulting from such statistical dependence can be overcome by using original data or Monte-Carlo derived scenarios in an integer linear programming model. The proposed optimization model should be of moderate size in typical applications, and by exploiting its special structure it can be solved optimally by standard methods. When this is uneconomical it may be solved approximately by efficient heuristics. Applications of these ideas have already been made to the detection of glaucoma. This paper focuses on possible applications in exploratory drilling for petroleum.
Delay analysis of a two-queue, nonuniform message channel

A Message Channel is defined as a tandem connection of single server queues in which the successive service times experienced by any particular customer are scaled versions of the same random variable, and thus it serves as a model for sparsely connected store-and-forward data communications networks (or network segments) where messages typically preserve their lengths as they traverse the system . A particular instance of sucha nonstandard queueing model is analyzed in this paper. The system consists of two single server queues in tandem subject tao Poisson arrival process (at the first queue) and providing service according to scaled versions of a sequence of two-level, discrete random variables. A set of recursive equations that can be used to solve the model for any given scaling factor at the second queue (normalized with respect to the first queue service) is explicitly derived. In addition, complete solutions are displayed for several cases of interest, and the equilibrium mean cumulative waiting times for these instances are compared as a method of indicating the impact of the scaling factor on the operation of the system. The extension of several results to systems with more general service time processes is discussed.
Clinical Hypothyroidism in the Elderly—A Preventable Disorder?*

: Among 27 ambulatory aged patients receiving thyroxine therapy for hypothyroidism, 4 had the “failing thyroid syndrome” (FTS) and 23 had frank clinical hypothyroidism. Patients with FTS are asymptomatic and the subnormal thyroid function is recognized only by a high level of serum thyrotropin (TSH) with a normal level of thyroid hormone (thyroxine or triiodothyronine). They require a smaller dosage of thyroid hormone for replacement initially. Identification of these cases through routine blood analyses for TSH in patients at risk (those with a history of Graves' disease or Hashimoto's thyroiditis) may permit early treatment of incipient hypothyroidism and the prevention of clinical hypothyroidism. Since there is a reduction in the thyroxine dosage required for complete thyroid replacement with age, the expected final replacement dosage when the thyroid fails completely is less than that reported for younger adults. This is true for patients with FTS, for patients with newly diagnosed clinical hypothyroidism, and for patients with long-established hypothyroidism receiving replacement therapy. The thyroid replacement dosage should be adjusted both for age and for body weight to avoid overdosage and thyroid toxicity, to which the elderly are particularly sensitive.
Abnormal Sympathetic Reactivity to the Cold Pressor Test in Overweight Humans

Overweight individuals (body mass index (BMI) 25–29.9 kg/m2) are at higher risk for developing hypertension and cardiovascular disease when compared with lean individuals of normal weight (BMI 18.5–24.9 kg/m2).1,2 The mechanisms underlying the increased risk have not been fully elucidated, but may include abnormalities of the sympathetic nervous system (SNS). Chronic baseline sympathetic overactivity, as well as greater sympathetic responses to stressful stimuli, are potential abnormalities that might predispose overweight individuals to developing hypertension and cardiovascular disease. Heightened cardiovascular and sympathetic reactivity to stressful stimuli has been associated with the development of hypertension and cardiovascular disease.3–7 Increased cardiovascular reactivity to the cold pressor test (CPT), a known sympathoexcitatory stimulus,8 predicts the future development of hypertension,9 and may represent a preclinical manifestation of hypertension before elevations in peripheral arterial blood pressure (BP) are detected. Augmented sympathetic reactivity may be one possible mechanism underlying the increased risk of developing hypertension and cardiovascular disease in overweight individuals, especially because sympathetic activity is known to be chronically elevated in obesity (BMI ≥30 kg/m2),10–12 and likely contributes to the pathogenesis of obesity-related hypertension. It is less established if overweight individuals, with a lesser degree of excess weight than obese patients, also have heightened baseline SNS activity, and sympathetic responses to sympathoexcitatory stimuli have never before been studied in normotensive overweight individuals. The purpose of this study was to test the hypothesis that normotensive overweight individuals have chronic baseline sympathetic overactivity, and exaggerated pressor and SNS responses to stressful stimuli. To test this hypothesis, we made hemodynamic measurements and direct measurements of muscle sympathetic nerve activity (MSNA) using microneurography at baseline and during two sympathoexcitatory maneuvers (CPT and static handgrip exercise (SHG)) in healthy overweight individuals, and lean age-matched controls.
Mechanisms of Intergranular Fracture

We present a study of the atomistic mechanisms of crack propagation along grain boundaries in metals and alloys. The failure behavior showing cleavage crack growth and/or crack-tip dislocation emission is demonstrated using atomistic simulations for an embedded-atom model. The simulations follow the quasi-equilibrium growth of a crack as the stress intensity applied increases. Dislocations emitted from crack tips normally blunt the crack and inhibit cleavage, inducing ductile behavior. When the emitted dislocations stay near the crack tip (sessile dislocations), they do blunt the crack but brittle cleavage can occur after the emission of a sufficient number of dislocations. The fracture process occurs as a combination of dislocation emission/micro-cleavage portions that are controlled by the local atomistic structure of the grain boundary. The grain boundary is shown to be a region where dislocation emission is easier, a mechanism that competes with the lower cohesive strength of the boundary region.
Muscular dystrophy and other myopathies: sarcotubular vesicles in early disease

Abstract Sarcotubular vesicles from patients with certain types of muscular dystrophy or polymyositis show a diminished ability to remove calcium from very dilute solutions (decreased calcium affinity), whereas in some of these patients the capacity of vesicles to accumulate calcium, in the presence of excess calcium, is normal. Decreased calcium affinity is detectable in these disorders when oxidative phosphorylation of concomitantly isolated mitochondria is normal. It is not found in a wide variety of other muscular or neuromuscular diseases.
The Web of Production: The Economic Geography of Commercial Internet Content Production in the United States:

This paper provides a description and analysis of the clustering behavior of the commercial Internet content industry in specific geographical locations within the United States. Using a data set of Internet domain name developed in the summer of 1998, I show that three regionsSan Francisco, New York, and Los Angelesare the leading centers for Internet content in the United States in terms both of absolute size and of degree of specialization. In order to understand better how the industrial structure of a region impacts the formation of the Internet content business, I provide an analysis of how the commercialization of the Internet has changed from 1993 to 1998 and explore the relationship between existing industrial sectors and the specialization in commercial domain names. Over time there appears to be a stronger connection between Internet content and information- intensive industries than between Internet content and the industries providing the computer and telecommunications technology necessary for the Internet to operate. Although it is not possible to assign a definitive causal explanation to the relationships outlined here, this paper provides a first step in theorizing about the overall commercialization process of the Internet.
Nucleus Accumbens 1, a Pox virus and Zinc finger/Bric-a-brac Tramtrack Broad protein binds to TAR DNA-binding protein 43 and has a potential role in Amyotrophic Lateral Sclerosis.

Abstract Protein degradation is a critical component of cellular maintenance. The intracellular translocation and targeting of the Ubiquitin Proteasome System (UPS) differentially coordinates a protein’s half-life and thereby its function. Nucleus Accumbens 1 (NAC1), a member of the Pox virus and Zinc finger/Bric-a-brac Tramtrack Broad complex (POZ/BTB) family of proteins, participates in the coordinated proteolysis of synaptic proteins by mediating recruitment of the UPS to dendritic spines. Here we report a novel interaction between NAC1 and TAR DNA-binding protein 43 (TDP-43), a protein identified as the primary component of ubiquitinated protein aggregates found in patients with Amyotrophic Lateral Sclerosis (ALS). In vitro translated full-length TDP-43 associated with both the POZ/BTB domain and the non-POZ/BTB domain of NAC1 in GST pulldown assays. Other POZ/BTB proteins (including zinc finger POZ/BTB proteins and atypical POZ/BTB proteins) showed weak interactions with TDP-43. In addition, NAC1 and TDP-43 were present in the same immunocomplexes in different regions of mouse brain and spinal cord. In primary spinal cord cultures, TDP-43 expression was mainly nuclear, whereas NAC1 was both nuclear and cytoplasmic. In order to mimic ALS-like toxicity in the spinal cord culture system, we elevated extracellular glutamate levels resulting in the selective loss of motor neurons. Using this model, it was found that glutamate toxicity elicited a dose-dependent translocation of TDP-43 out of the nucleus of cholinergic neurons and increased the co-localization of NAC1 and TDP-43. These findings suggest that NAC1 may function to link TDP-43 to the proteasome; thereby, facilitating the post-translational modifications of TDP-43 that lead to the development of ALS.
A note on computing elastodynamic full field displacements arising from subsurface singular sources

Abstract : This reprint is directed at developing a Green's function for a two- dimensional, isotropic half-space. The article addresses the buried impulsive single force as formulated by Hudson; however other loadings and sources such as Garvin's problem could also be handled by the method presented. Starting with the formal solution, a numerical root finding scheme is employed to compute terms which normally present problems for general field points below the free surface.
CURSOS Y DISCURSOS ESCOLARES EN LAS TRAYECTORIAS JUVENILES

Diferentes estudios sobre juventud han venido adoptando el enfoque de trayectorias como una entrada al fenomeno juvenil. La potencia de este enfoque es que permite ligar en un mismo ejercicio analitico las dimensiones estructurales, educacionales y laborales que influyen en el proceso de construccion social de juventudes. Su aplicacion ha resultado de gran relevancia para entender las condiciones juveniles en paises europeos. Sin embargo, en Chile han existido pocas iniciativas de investigacion que intenten este tipo de aproximaciones. El presente articulo intenta aplicar el enfoque de trayectorias al analisis de un sector especifico de la juventud: la que asiste a los establecimientos de educacion publica municipal. El proposito es intentar describir la trayectoria de estos jovenes abordando de manera integrada sus caracteristicas estructurales o de origen, sus trayectos escolares y la exploracion de los distintos modos en que proyectan su futuro en los planos educacional, laboral y familiar.
Modeling coupled heat and mass transfer for convection cooking of chicken patties

Abstract A 2-D axisymmetric finite element (FE) model was developed to simulate coupled heat and mass transfer during convection cooking of regularly shaped chicken patties, given actual transient oven air conditions. Transient temperature and moisture distributions inside the product were predicted, and 98 chicken patties were cooked in a convection oven for model validation. The predicted transient center temperature under various cooking conditions had an error of 3.8–5.7°C, as compared to experimental data. The prediction error for the cooking yield was 1.2%. For the same cooking conditions, the prediction error would increase to 5.9–12.9°C if mass transfer were ignored in simulation. The best prediction was obtained when both thermal conductivity and specific heat were modeled as state-dependent functions in the simulation.