cssi/SciSciGPT-SciSciNet huggingface dataset:
NEW INSIGHT INTO THE OPTICAL PROPERTIES OF AMORPHOUS Ge AND Si

Abstract A short range disorder model, unlike present long range disorder theories, has been able to account well for both the density of states and the optical properties of amorphous Ge and Si. Our results indicate that the imaginary part of the dielectric function for amorphous Ge and Si has the same form as an averaged gradient matrix element as a function of energy. This conclusion should be valid for all tetrahedrally bonded amorphous solids.
Urinary Triclosan is Associated with Elevated Body Mass Index in NHANES

Background Triclosan—a ubiquitous chemical in toothpastes, soaps, and household cleaning supplies—has the potential to alter both gut microbiota and endocrine function and thereby affect body weight. Methods We investigated the relationship between triclosan and body mass index (BMI) using National Health and Nutrition Examination Surveys (NHANES) from 2003–2008. BMI and spot urinary triclosan levels were obtained from adults. Using two different exposure measures—either presence vs. absence or quartiles of triclosan—we assessed the association between triclosan and BMI. We also screened all NHANES serum and urine biomarkers to identify correlated factors that might confound observed associations. Results Compared with undetectable triclosan, a detectable level was associated with a 0.9-point increase in BMI (p<0.001). In analysis by quartile, compared to the lowest quartile, the 2nd, 3rd and 4th quartiles of urinary triclosan were associated with BMI increases of 1.5 (p<0.001), 1.0 (p = 0.002), and 0.3 (p = 0.33) respectively. The one strong correlate of triclosan identified in NHANES was its metabolite, 2,4-dichlorophenol (ρ = 0.4); its association with BMI, however, was weaker than that of triclosan. No other likely confounder was identified. Conclusions Triclosan exposure is associated with increased BMI. Stronger effect at moderate than high levels suggests a complex mechanism of action.
Analysis of the detection of organophosphate pesticides in aqueous solutions using polymer-coated SH-SAW sensor arrays

There is a need for on-site and real time detection of organophosphate pesticides in aqueous environments. This work proposes the use of polymer coated shear horizontal surface acoustic wave (SH-SAW) sensors as a sensing platform for detection of organophosphate pesticides in aqueous environments. The chemically sensitive polymer coatings BPA-HMTS and BPA-PDMS, synthesized in-house, and the commercially available polymer PECH, were chosen as sensor coatings for organophosphate detection. The polymers are characterized at various thicknesses (0.25μm and 0.50μm) for their selectivity and sensitivity towards parathion, parathion-methyl, and paraoxon. A sensor array is designed for analyte identification and quantification using both steady-state and transient response information. Analyte identification is performed using a visual pattern recognition technique based on radial plots for the analytes at concentrations from 0.5mg/L to 3.0mg/L. It is shown that using the absorption time constant, which is unique to a given analyte-coating pair, in conjunction with steady-state frequency shifts permits direct identification and quantification of organophosphate pesticides in liquid-phase at low-ppm and sub-ppm concentrations.
Position of helical kinks in membrane protein crystal structures and the accuracy of computational prediction.

Abstract The structural features of helical transmembrane (TM) proteins, such as helical kinks, tilts, and rotational orientations are important in modulation of their function and these structural features give rise to functional diversity in membrane proteins with similar topology. In particular, the helical kinks caused by breaking of the backbone hydrogen bonds lead to hinge bending flexibility in these helices. Therefore it is important to understand the nature of the helical kinks and to be able to reproduce these kinks in structural models of membrane proteins. We have analyzed the position and extent of helical kinks in the transmembrane helices of all the crystal structures of membrane proteins taken from the MPtopo database, which are about 405 individual helices of length between 19 and 35 residues. 44% of the crystal structures of TM helices showed a significant helical kink, and 35% of these kinks are caused by prolines. Many of the non-proline helical kinks are caused by other residues like Ser and Gly that are located at the center of helical kinks. The side chain of Ser makes a hydrogen bond with the main chain carbonyl of the i − 4th or i + 4th residue thus making a kink. We have also studied how well molecular dynamics (MD) simulations on isolated helices can reproduce the position of the helical kinks in TM helices. Such a method is useful for structure prediction of membrane proteins. We performed MD simulations, starting from a canonical helix for the 405 TM helices. 1 ns of MD simulation results show that we can reproduce about 79% of the proline kinks, only 59% of the vestigial proline kinks and 18% of the non-proline helical kinks. We found that similar results can be obtained from choosing the lowest potential energy structure from the MD simulation. 4–14% more of the vestigial prolines were reproduced by replacing them with prolines before performing MD simulations, and changing the amino acid back to proline after the MD simulations. From these results we conclude that the position of the helical kinks is dependent on the TM sequence. However the extent of helical kinking may depend on the packing of the rest of the protein and the lipid bilayer.
MYOCARDIAL BIOPSY IN INFANCY AND CHILDHOOD: MODIFIED SMOOTH MUSCLE CELLS IN ENDOCARDIAL ELASTOMYOFIBROSIS

Ten patients, aged 4.5 months to 7 years with cardiomyopthies (9 congestive) had transvascular myocardial biopsies by a miniaturized technique. 4 had endocardial thickening defined as >20μ of left ventricle (LV). LV endocardium was not thick ened in the one patient with LV myocardial interstitial fibrosis. LV endocardial thickening resulted from the increase ot two layers adjacent to the myocardium, the smooth muscle (SM) layer (normally only a few SM cells) and the subendocardial layer (normally connective tissue, capillaries, ummyelinated nerves and a few cells). Thickening was due to increase in cells, elastic fibers and collagen fibers without inflammatory cells or increased capillaries. Cell morphology changed from (a) an innermost (toward the lumen) layer of dark SM cells with surface vesicles and myofilaments to (b) light SM cells with fewer vesicles and myofilaments to (c) “leiomyoid” cells resembling both SM cells and fibroblasts, partly lacking basement membrane but containing fusiform densities, myofilaments, rough endoplasmic reticulum. ribosomes and Golgi to (d) typical fibroblasts. Light SM cells may be able to divide. Elastin is found adjacent to leiomyoid cells and may be formed by these cells. These findings may shed light on the genesis of “endocardial fibroelastosis.”
Photoassisted electrochemical micromachining of silicon in HF electrolytes

Abstract We have demonstrated the ability to fabricate stress-free micromechanical cantilever beams by selective etching of silicon p—n structures in HF solutions utilizing a photoassisted electrochemical process. A particular novelty of this technique is that n or p regions of a p—n structure may be selectively etched at controlled rates by appropriate choice of cell bias, p—n junction bias, and illumination intensity. p-Si is selectively etched by either one of two ways. Illumination of the p—n junction serves to bias the p-layer anodically relative to the n-substrate, resulting in etch rates of up to 0.6 μm/min. Alternatively, p-Si etch rates up to 10 μm/min are attained without illumination by short circuiting the p—n junction and anodically biasing the n-Si substrate. n-Si, on the other hand, is selectively etched at rates up to 10 μm/min by illuminating and reverse biasing the p—n junction, driving the p-layer cathodic. At etch rates below approximately 1 μm/min, porous silicon layers form, which can be subsequently removed with chemical etchants. These processes are characterized by high-resolution etch-stops with smooth surfaces, rendering them potentially attractive for micromachining purposes. The effects of key variables, including doping type, cell bias, p—n junction bias, and illumination intensity, on etch rate, selectivity, and surface finish are discussed.
The Effects of Pre-university Study of Journalism on Entry to the Job Market

Research in the United States has shown that extracurricular activities at the high school level are beneficial for students. One type of extracurricular activity common in U.S. high schools is journalistic, including production of a student newspaper, involvement with student radio and television, and production of a yearbook. Little is known about the lasting effects of participation in high school extracurricular communication activities. This article examines the impact of participation in high school extracurricular communication activities on initial success in the job market, using data from a national sample of journalism and mass communication graduates.
Sex Roles and Internal Labor Market Structures: The “Female” Semi-Professions

After drawing a distinction between internal and external labor market analysis, patterns in the sex structure of employment markets in nursing, social work, librarianship, and school teaching are examined. Findings indicate that the relative number of men employed in these “female” fields has increased and that males are disproportionately represented in the administrative components of the “female” semi-professions. The role which internal labor market structures play in determining the continuance of boundaries to “male” and “female” work is discussed.
Structural Study of a Laramide Fold Involving Shallow-Seated Basement Rock, Front Range, Colorado

An anticline three miles west of Loveland, Colorado, exposes Precambrian basement rock, and permits a study of fold mechanisms within the en echelon fold belt of the Colorado Front Range. The contrast in mechanical properties between basement rock and superjacent sediments has resulted in two entirely different mechanisms of folding in this area. Studies of fold geometry, jointing, and stratigraphic thickness indicate that the sedimentary rocks yielded to Laramide stresses by concentric folding, up to a limiting curvature. Thereafter, additional displacements took place by faulting across the steeper limb of the anticline. The relationships of Precambrian structures to the fold geometry indicate that basement adjustments to Laramide stresses took place by differential movement along pre-existing fractures, within a zone adjacent to the unconformity that separates the basement from the sedimentary cover. In the lower basement zone, displacement along high angle reverse faults is virtually the only recognizable feature of Laramide deformation.
Design-driven harmony search (DDHS) in steel frame optimization

Abstract Recent research efforts in the field of steel frame optimization have demonstrated the successful implementation of stochastic methods such as genetic algorithms, simulated annealing, ant colony optimization, particle swarm, and harmony search in obtaining least-weight designs. The stochastic nature of these methods is effective in scouring the large design space of discrete variables intrinsic to steel frame optimization problems. However as the randomness of these methods can limit the optimality of the frame designs obtained, the frequency with which these designs are obtained, and the computational effort required to obtain them, no one algorithm has distinguished itself as most effective. This paper presents a design-driven harmony search (DDHS) algorithm for optimization of steel moment frames. Based on the harmony search method, DDHS incorporates intelligence in the stochastic search DDHS by using constraint satisfaction or violation data from previous trial solutions to steer the optimization in the direction of larger or smaller sections as sorted by an appropriate section parameter. Thus, DDHS generates random trial solutions within intelligently specified search neighborhoods, resulting in improved performance in steel frame optimization as measured by the optimality of the designs obtained, the consistency with which successive runs obtain these designs, and the number of structural analyses required to obtain them. This paper demonstrates the efficient performance of DDHS as applied to three benchmark problems – a 15-member, a 105-member, and a 168-member planar frame optimization.
WE-D-224C-04: Investigation of MLC Effects On Secondary Neutron Spectra for Varian, Siemens, and Elekta

Purpose: To compare the secondary neutron spectra in accelerators with different multileaf collimator(MLC) configurations. The addition of MLC, have lead to design modifications in modern linear accelerators; Elekta has replaced upper collimating jaws with MLC, Siemens has replaced lower jaws with MLC, Varian added tertiary level MLC.Method and Materials: Measurements were made of the neutron fluence and energy spectra for several modern accelerators. The detector consisted of 197Au activation foils, which were placed on the surface of the holder and inserted into Bonner Spheres. An HPGe detector was used to measure counts under the 411keV photopeak for each foil. Data were unfolded with the MXD_FC33 code with a response matrix specifically calculated for this measurement system using MCNP5. In this investigation, neutron spectra, fluence per MU, and ambient dose equivalent are reported for 18MV x‐ray beams generated by Varian 21EX, Siemens Oncor, and Elekta Precise accelerators. The impact of the jaw and MLC configuration were further studied for the Varian 21EX by taking measurements following the complete removal of the MLC.Results:Jaws and MLC closed: similar spectra for the Siemens and Elekta but the Varian spectrum has a lower energy distribution. Varian X and Y jaws closed: With MLC in place, less neutrons are detected and spectrum shifts to lower energies (compared to MLC removed). MLC attenuates neutrons created higher in treatment head. Varian X and Y jaws retracted: With MLC in place more neutrons are detected and the spectra shifts to lower energies (compared to MLC removed). The MLC attenuate neutrons created higher in treatment head but MLC become the primary source of contamination neutrons when jaws retracted. Conclusion: Secondary neutron spectra are different in accelerators with different MLC configurations. This difference translates to a difference in ambient dose equivalent to patients receiving high‐energy radiation therapy.
Development of sorting, aligning, and orienting motile sperm using microfluidic device operated by hydrostatic pressure

In vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) are the most commonly used assisted reproductive technologies to overcome male infertility problems. One of the obstacles of IVF and ICSI procedures is separating motile sperm from non-motile sperm to select the most competent sperm population from any given sperm sample. In addition, orientation and separation of the head from the tail is another obstacle for ICSI. Using the self-movement of sperm against flow direction, motile and non-motile sperm can be separated with an inexpensive polymeric microfluidic system. In this paper, we describe the development of a microfluidic system obtained through low-cost fabrication processes. We report experimental results of sperm sorting using hydrostatic pressure of three different species: bull, mouse, and human. The movement of cells in these channels was observed under a microscope and recorded with a digital camera. It is shown that the hydrostatic pressure and self-movement of motile sperm can be used to solve separating, aligning and orienting sperm in the microchannel.
Molecular MRI of Thrombosis

This review focuses on recent approaches in using targeted MRI probes for noninvasive molecular imaging of thrombosis. Probe design strategies are discussed: choice of molecular target; nanoparticle versus small-molecule probe; and gadolinium versus iron oxide imaging reporter. Examples of these different design strategies are chosen from the recent literature. Novel contrast agents used to image direct and indirect binding to fibrin have been described as well as direct binding to activated platelets. Emphasis is placed on probes where utility has been demonstrated in animal models or in human clinical trials.
Nitrogen quadrupole coupling in paraelectric ammonium sulfate

Abstract The quadrupole coupling parameters for pre14N in the two chemically inequivalent sites in paraelectric ammonium sulfate have been measured by proton-nitrogen double resonance for the interval 225 ≤T≤365 K. Transition frequencies are represented to within ca. 0.2 kHz in this interval by v+ (I) = 242.43 - 0.3380T; v−(I) = 144.03 - 0.1855 T; v(II)=147.08 - 0.1294 T; v− (II) = 73.39 - 0.0281 T kHz, where T is the temperature in degrees Kelvin. These data are discussed in the context of neutron diffraction thermal parameters and an STO-3G calculation of the field gradients at the two sites. Although the temperature dependence is qualitatively in agreement with the structure data, the discrepancy between the calculated and observed asymmetry parameters, particularly for site I, suggests that hydrogen bonding to sulfate is an important feature in determining the ammonium ion charge distribution and hence the field gradient tensor at nitrogen. At 296.1 K the coupling parameters are e2gQ/h (I) = 154.53 kHz, η(I) = 0.684; e2gQ/h (II) = 115.71 kHz, η1(II) = 0.749.
Analysis of Basal Regulatory Elements in the 25-Hydroxyvitamin D3 1α-Hydroxylase Gene Promoter☆

Abstract 5′-Deletion analysis of the 1.7-kb mouse 1α-hydroxylase gene promoter reveals that the minimal promoter region for basal activity is −85/+22 and requires a functional CCAAT element. Mutational analysis also demonstrates that deletion of the internal promoter region from nucleotides −1125 to −86 leads to a 25- to 30-fold increase in basal promoter activity. The increased activity is not the result of positional effects, but is caused in part by the removal of an AC repeat. Further analysis of the promoter revealed an enhancer element localizes to an upstream region −1385 to −1125, which contains three consensus AP-1 sites. Deletion of the most proximal AP-1 site causes a 60% loss of enhancer activity. The data suggest the presence of the AC repeat prevents the full potential activation of the 1α-hydroxylase promoter by factors binding to AP-1 sites.
A simple method of cannulating the portal vein and obtaining multiple blood samples in the rat.

A simple and rapid technique for cannulating the portal vein in the rat is described. Multiple blood samples can be obtained or alternatively substrate may be infused through the cannula.
THE AMERICANS WITH DISABILITIES ACT: TEN YEARS LATER

The Americans With Disabilities Act (ADA), signed into law on July 26, 1990, was full of promises but was also vague and in some ways contradictory. However, the ADA did bring official recognition to the country's largest minority group and focused attention on the need for making basic life activities available and accessible to an estimated 50 million or more Americans. This article provides an overview of the ADA 10 years after its passage into law, focusing on the emergence of disability policy studies, major provisions of the ADA, and policy outcomes.
Thickening of clay slurries by periodic pressure flow through a porous polyethylene tube

Abstract A periodic pressure filtration process is evaluated to determine if the process can be used to thicken clay slurries. Current environmental cleanup operations, such as soil washing, result in large volumes of dilute slurries that must be filtered to remove the particles. The soil particles collected during the filtration, if clean, can be returned to the ground. One step in the dewatering and filtering process is thickening the slurry before filtering. The periodic pressure filtration process is one possible process for thickening clay slurries, but no performance data are available for evaluating the process. In this work a one-tube periodic pressure filter process is evaluated by measuring the thickened slurry discharge and filtrate rate while varying the design and operating parameters. The experimental results show that the process can thicken slurries of 1 to 3% inlet mass concentration to about 30 to 40% mass concentration.
Intrusion Characteristics in the Antarctic Polar Front

Abstract Data obtained on two cruises to the Antarctic Polar Front are used to investigate the nature of thermohaline intrusions in the front. These data, obtained in the Drake Passage and south of New Zealand, include CTD time series made relative to neutrally buoyant vertical-current meters, temperature data from these floats, and small-scale CTD sections. Analysis of these data is divided into a study of temporal persistence and an examination of the spatial structure of the intrusions. The study of intrusion time scales is hampered by the presence of large spatial gradients in the intrusion field. This study suggests that features are persistent for several days but additional measurements appear necessary to resolve the intrusion decay process. The length scales of intrusions are found to vary within the frontal zone. Near the region of maximum lateral gradients in the front, length scales of 5 to 10 km are observed, while elsewhere scales of only 1 km are found. It is suggested that these small, iso...
Axisymmetric shell elements for heat conduction with p-approximation in the thickness direction

This paper presents a finite element formulation for the axisymmetric shell elements for heat conduction where the element temperature approximation in the direction of the shell thickness can be of an arbitrary polynomial order p. This is made possible by introducing additional nodal variables in the element temperature approximation corresponding to the complete Lagrange interpolating polynomials in the direction of the shell thickness. The elements presented have an important hierarchical property, i.e. the element properties corresponding to an approximation order p are a subset of the properties corresponding to an approximation order p + 1. The element formulation retains continuity or smoothness of temperature across the interelement boundaries, i.e. C0 continuity is enforced automatically.The axisymmetric shell geometry is constructed in the usual way by using the coordinates of the nodes lying on the middle surface of an element (Â? = 0) and the node point normals to the middle surface. The element temperature approximation consists of hierarchical approximation functions, nodal temperatures and the derivatives of the nodal temperatures corresponding to the complete polynomials in the direction of the shell thickness. The weak formulation (or the quadratic functional) of the Fourier heat conduction equation is constructed. The element properties are derived using weak formulation (or the quadratic functional) and the hierarchical element approximation. The element matrices and the equivalent heat vectors (resulting from convective boundaries, distributed heat flux and internal heat generation) are all hierarchical. The element formulation permits a temperature distribution of any desired order in the shell thickness direction.Numerical examples demonstrate the accuracy, efficiency and overall superiority of the present formulation over existing axisymmetric shell elements. The results are also compared with analytical solutions and for all four examples, h-approximation results are presented for comparison.
Composition of the basic fraction of marijuana and tobacco condensates: A comparative study by capillary GC/MS

Combined capillary gas chromatography/mass spectrometry has been used to characterize the basic fraction of Mexican marijuana and standard tobacco smoke condensates. A thermostable Superox-coated glass capillary column permitted elution of relatively large nitrogen-containing compounds. Substantial qualitative and quantitative differences between the two materials were noted.
Temperature effects on mitochondrial respiration of Protophormia terranovae and Musca domestica

Abstract Oxygen electrode measurements of the respiratory activity of coupled mitochondria from adult Protophormia terranovae (which accumulates glycerol under cold stress) and Musca domestica (which does not) were conducted. Enthalpies of activation (-Ha's) were calculated from respiratory rate data obtained between +2°C and +26°C with sn-glycerol-3-phosphate as substrate. Both species have very similar — Ha's between +12°C and +26°C for respiratory states 3 and 4 and the uncoupled state. Below +11.5°C the enthalpy values for state 3 respiration increase 65% for P. terranovae and 122% for M. domestica while state 4 and uncoupled state rate values remain unchanged. These results demonstrate that since ADP requiring processes in oxidative phosphorylation become rate limiting for both species below +11.5°C they cannot regulate low temperature induced glycerol accumulation by P. terranovae. Calculations of Q10 values through a series of temperature ranges indicate that, as expected, P. terranovae shows a greater facility for low temperature adaptation for state 3 oxidation than M. domestica.
Structures In the Rio Grande And Kenyan Rift: A Comparison

The Rio Grande rift gradually widens from its northern terminus in Colorado to southern New Mexico, Texas, and the northern portion of the state of Chihuahua, Mexico, where it appears to merge with the Basin and Range province. In a similar fashion, the Kenya rift widens from the apex of the Kenya topographic dome near Nairobi northward toward the Lake Turkana region, where the rift becomes diffuse as it enters Ethiopia. Recent studies in Kenya conducted by the Kenya Rift International Seismic Project (KRISP), project PROBE, and Amoco have provided a much improved picture of structural relationships in this rift zone. In the Rio Grande rift, efforts by many workers continue to reveal an ever clearer picture of structural relations. These two rift zones appear to possess some common characteristics which may be useful in studies of other rift zones. A combination of data indicate that the wider portions of both rifts are also the most extended. This observation is in agreement with the decrease in elevation and crustal thickness as the rifts widen. In both rifts, the subsurface structure of the basins is much more complex than the surface expressions would indicate. Half-graben geometrics predominate, but the relations between major faults and rift flank topography is not always that which would be expected. The most extended regions of these rifts seem to have preserved the thickest pre-rift sedimentary sections. This relationship is effected by pre-rift geologic history, but does suggest these regions would be the best exploration targets.
Thermal dependence of serotonergic modulation of neural activity in the hamster.

1. The modulatory effect of serotonin on CA1 pyramidal cells in the hamster (Mesocricetus auratus) hippocampus was examined over a range of temperatures. 2. Following repetitive Schaffer collateral/commissural stimulation, changes in the amplitude of population spikes (the synchronous firing of CA1 pyramidal cells) were recorded in the hamster, a hibernator. Amplitudes were measured after 10 μM sero tonin was added to and then withdrawn from the perfusing medium with the temperature of the bath fixed at different temperatures. 3. Between 35 °C and 15 °C a depression in population spike amplitude of at least 10% was seen in 36 of 43 trials, with an average depression of 68%. No significant temperature dependence of the depressive effect was seen. 4. Following the removal of serotonin from the perfusate, the spike amplitude was enhanced over the same range of temperatures, averaging 33% higher than control values. The enhancement was most pronounced at 35 °C and 15 °C and smallest at 25 °C. 5. Thus, over the entire temperature range of 35 °C to 15 °C, serotonin exerted a dual modulatory effect on the spike amplitude, a depression followed by an enhancement. Serotonin's modulatory effects on pyramidal cell excitation persist over temperatures encountered as the hamster enters hibernation.
Nanoscale mechanics of solid-supported multilayered lipid films by force measurement

Using atomic force microscopy and molecular force probe, we have studied the structure and nanomechanical response to nano-indentation of multilayered films of dioleoylphosphatidylcholine films prepared by solution spreading, spin-coating, and capillary methods. The influence of the film thickness on the apparent elastic (Young's) modulus is investigated. Young's moduli of samples prepared by the different methods were found to be similar for sufficiently thick films. An ostensible influence of substrate coupling on the apparent Young's modulus is observed for thinner lipid films. The results are discussed in comparison with previously reported estimates for supported lipid bilayers (membranes) and cells.
Controlling synchrony in a network of Kuramoto oscillators with time-varying coupling

Abstract The Kuramoto model describes the synchronization of a heterogeneous population of oscillators through a stationary homogeneous network in which oscillators are coupled via their phase differences. Recently, there has been interest in studying synchronization on time-varying networks, and time-varying generalizations of the Kuramoto network, in particular. Previous results indicate that networks with fast dynamics may be as efficient as static networks at promoting synchrony. In this paper we use optimal control theory to study synchronization on a time-varying Kuramoto network. Our results indicate that time-varying networks can be more efficient than static networks at promoting synchrony and show that fast network dynamics are not necessary for efficiency. In particular, we show that, near the synchronization threshold, time-varying networks can promote synchrony through slow oscillations that lengthen the duration of high synchrony states and shorten the duration of low synchrony states. Interestingly, repulsion is an essential feature of these optimal dynamic networks.
Measurement error and minimum detectable change in 4-meter gait speed in older adults

Background and aims: Gait speed is a commonly-used assessment and outcomes measure in geriatric clinical and research settings. Although relative reliability of usual gait speed has been well studied in community-dwelling older adults, less emphasis has been placed on a measure of absolute reliability (the standard error of measurement [SEM]), and on an associated clinically relevant index of real change in gait speed, minimum detectable change (MDC). The purpose of this study was to quantify measurement error and MDC for usual gait speed over 4 meters in community-dwelling older adults ambulating at intermediate and fast speeds. Methods: Community-dwelling older adults ambulating at intermediate gait speed (IGS), (n=15, mean age 74.2 yrs) and fast gait speed (FGS), (n=15, mean age 72.1) were included in this study. Participants performed two trials of gait speed over a distance of 4 meters. SEM and MDC at the 95% confidence level (MDC95) were computed for the IGS and FGS groups. Results: Mean gait speed was 85.4 cm/s (IGS) and 129.9 cm/s (FGS). Measurement error (<5% of mean gait speed) and minimum detectable change (<13% of mean gait speed) were low in both groups. MDC95 was computed as 10.8 cm/s and 14.4 cm/s for the IGS and FGS groups, respectively. Conclusions: To be considered real change beyond the bounds of measurement error, change in 4-meter gait speed should exceed 10.8 cm/s (for intermediate speed ambulators) or 14.4 cm/s (for fast speed ambulators). Low measurement error in assessing 4-meter gait speed in community-dwelling older adults suggests that gait speed assessed over short distances has excellent reproducibility across trials. Low minimum change values suggest that 4-meter gait speed may be responsive and sensitive to change.
The Indus Valley Tradition of Pakistan and western India

Over the last several decades new sets of information have provided a more detailed understanding of the rise and character of the Indus Civilization as well as its decline and decentralization. This article begins with a summary of the major historical developments in the archaeology of the Indus Valley Tradition and a definition of terms found in the literature. A general discussion of the environmental setting and certain preconditions for the rise of urban and state-level society is followed by a summary of the major aspects of the Harappan Phase of the Indus Valley Tradition. This summary includes discussions of settlement patterns, subsistence, architecture, trade and exchange, specialized crafts, language, religion, and social organization. The Localization Era or decentralization of the urban centers is also addressed.
Transcatheter closure of modified Blalock‐Taussig shunt with Gianturco‐Grifka vascular occlusion device

A 15-year-old girl with previous repair of a complex cyanotic congenital heart defect had persistence of a modified left Blalock-Taussig shunt that could not be ligated at surgery. Six years later, antegrade delivery of a Gianturco-Grifka Vascular Occlusion Device resulted in complete closure of the shunt. Cathet. Cardiovasc. Intervent. 48:365-367, 1999.
Competitive formation of cellulose p-toluenesulfonate and chlorodeoxycellulose during homogeneous reaction of p-toluenesulfonyl chloride with cellulose in N,N-dimethylacetamide-lithium chloride

Abstract The homogeneous preparation of a cellulose p -toluenesulfonate (tosylate) in N,N -dimethylacetamide-lithium chloride (DMAc-LiCl) is hampered by solvolysis of the p -toluenesulfonyl chloride (tosyl chloride). This Vilsmeier-Haack type reaction results in competitive formation of cellulose p -toluenesulfonate and chlorodeoxycellulose. Highly p -toluenesulfonylated cellulose may be prepared in DMAc-LiCl with minimal incorporation of chlorine by utilization of either triethylamine or 4-dimethylaminopyridine as base. A mechanism for the competing series of reactions is postulated.
Free trade and garment work: the impact of NAFTA on service and manufacturing jobs in the Los Angeles apparel industry

This article examines the impact of North American economic integration on apparel-related employment in Los Angeles and provides a first look at consequent changes in the composite of apparel-related occupations in the Los Angeles apparel industry. It assesses the effects of new NAFTA-generated transnational production networks and global production strategies on apparel industry employment, including the creation of ‘new NAFTA jobs’in the greater Los Angeles area, as well as changes in hiring patterns across occupational categories. The article also explores the accessibility of NAFTA-generated apparel jobs to displaced workers in the labor-intensive segments of the industry. The findings suggest that the new NAFTA jobs are inaccessible to the thousands of apparel manufacturing workers displaced by the trend in offshore sourcing. Finally, the article discusses the implications and consequences of recent state-industry partnership programs designed to train and cross-train sewing operators for jobs that are rapidly leaving the region. Cet article examine l'impact de l'integration economique nord-americaine sur l'emploi dans l'habillement a Los Angeles, en procurant un premier regard sur les changements occasionnes pour la mosaique des metiers de ce secteur d'activites dans cette ville. Il evalue les effets des nouveaux reseaux de fabrication transnationale generes par l'ALENA et des strategies de production mondialisees sur l'emploi du secteur, y compris la creation des ‘nouveaux emplois ALENA’ dans l'agglomeration de Los Angeles, ainsi que les changements dans les schemas d'embauche pour les diverses categories professionnelles. De plus, il explore l'accessibilite des emplois de l'habillement crees par l'ALENA pour les travailleurs deplaces dans les segments industriels a forte main-d'œuvre. D'apres les resultats, ces nouveaux emplois sont inaccessibles aux milliers d'ouvriers de la fabrication vestimentaire deplaces par la tendance a un approvisionnement etranger. Enfin, sont abordees les implications et consequences des recents programmes de partenariat Etat-industrie pour la formation et la formation polyvalente d'operatrices de machines a coudre a des postes qui quittent rapidement la region.
A Sequence Alignment-Independent Method for Protein Classification

homologues and functional motifs in protein families. The most popular methods rely on sequence alignment. These include programs that use a scoring matrix to compare the probability of a potential alignment with random chance and programs that use curated multiple alignments to train profile hidden Markov models (HMMs). Related approaches depend on bootstrapping multiple alignments from a single sequence. However, alignment-based programs have limitations. They make the assumption that contiguity is conserved between homologous segments, which may not be true in genetic recombination or horizontal transfer. Alignments also become ambiguous when sequence similarity drops below 40%. This has kindled interest in classification methods that do not rely on alignment. An approach to classification without alignment based on the distribution of contiguous sequences of four amino acids (4-grams) was developed. Interest in 4-grams stemmed from the observation that almost all theoretically possible 4-grams (204) occur in natural sequences and the majority of 4-grams are uniformly distributed. This implies that the probability of finding identical 4-grams by random chance in unrelated sequences is low. A Bayesian probabilistic model was developed to test this hypothesis. For each protein family in Pfam-A and PIR-PSD, a feature vector called a probe was constructed from the set of 4-grams that best characterised the family. In rigorous jackknife tests, unknown sequences from Pfam-A and PIR-PSD were compared with the probes for each family. A classification result was deemed a true positive if the probe match with the highest probability was in first place in a rank-ordered list. This was achieved in 70% of cases. Analysis of false positives suggested that the precision might approach 85% if selected families were clustered into subsets. Case studies indicated that the 4-grams in common between an unknown and the best matching probe correlated with functional motifs from PRINTS. The results showed that remote homologues and functional motifs could be identified from an analysis of 4-gram patterns.
Robust Optical Stimulation of Neuronal Activity using Functionalized Gold Nanoparticles

It was recently shown that infrared light pulses can directly stimulate neuronal action potentials by quickly heating the cell membrane and inducing capacitive currents (Shapiro, et al., Nat Commun, 2012). While useful, this technique works by heating the entire aqueous environment around a cell, rendering it nonspecific and incapable of stimulating specific populations of cells. Furthermore, since water absorbs infrared, the light source must be near the target. Here, we sought to stimulate neurons with visible light, using the ability of 20 nm spherical gold nanoparticles (AuNPs) to absorb green light and convert it into heat. By applying the AuNPs to painted lipid bilayers, we first confirmed that, upon 532 nm pulse stimulation, the membrane capacitance increases following the rate of temperature increase. The resulting currents are well-behaved, being linear with respect to both laser power and membrane potential. We next applied AuNPs to cultured dorsal root ganglion (DRG) neurons and demonstrated action potential initiation with 532 nm pulses of ≤1 ms. Finally, we obtained a dramatic improvement of this technique by functionalizing AuNPs with high-avidity ligands for DRG neuron membrane proteins. Nonfunctionalized AuNPs are cleared away from DRG neurons within seconds of starting a perfusion wash, causing the cells to lose optical excitability. However, AuNPs functionalized with Ts1 neurotoxin, or with anti-TRPV1 or anti-P2X3 antibodies, showed substantial resistance to washout; DRG neurons labeled with these functionalized particles remained light-sensitive after more than 20 minutes of perfusion washing. Furthermore, these particles required a lower concentration and less laser power to confer optical excitability. By appropriate selection of AuNP-conjugated ligand, this technique may enable improved cell-type specificity of neuronal photostimulation, such as ganglion cells in diseased retina where photoreceptors are non-functional. Support: R21-EY023430 and The Beckman Initiative for Macular Research.
Carotid artery stenosis: Medical, surgical, and endovascular approaches

The treatment of carotid artery stenosis has undergone tremendous change in the last 15 years. Multiple important prospective randomized trials have proved the benefit of both medical therapy (with antiplatelet agents and anticoagulants) and surgical therapy for symptomatic and asymptomatic carotid artery stenosis. The choice of therapy in a large population of patients with carotid artery stenosis can be based on class I data from prospective randomized clinical trials. However, an equally large subset of patients with carotid artery stenosis fall outside the eligibility criteria of many of the clinical trials because of multiple factors that include medical comorbidities and anatomic considerations. With these patients, individual decisions must be reached as to the appropriateness of medical, surgical, or endovascular intervention based on a rational evaluation of the available medical literature and the experience of the treating physicians.
Infusing Computational Engineering Tools in Engineering Design Sequence Curricula

AbstractThis paper presents a project which aims at redesigning the curricula of engineering design sequence by infusing CAx tools in the design courses. Project strategies include the development of tutorials for the CAx tools, use of homework and projects to enhance students’ skills in using the software and understanding of fundamentals, and use of Teaching Assistants (TA) to tutor students and to develop tutorials. Results of project evaluation show that the project activities are very effective in improving the students’ learning of CAx tools and enhancing their understanding of theories. Feedback and future work are also discussed.
Diagnostic Methods for Evaluation of Stallion Subfertility: A Review

Abstract Classically, evaluation of the breeding stallion for reduced fertility has relied on physical examination of the reproductive system, as well as evaluation of sperm number, motility, and morphology. Over the past 20 years, a number of other diagnostic methods have become available to facilitate reproductive evaluation of the stallion. Specifically, ultrasound imaging has provided much-improved diagnostic methods for evaluation of the external and internal genitalia of the stallion, and these methods have now become routine in evaluation of the stallion. Biochemical analyses of semen can provide useful information for diagnosis of azoospermia (determination of alkaline phosphatase), detection of urine contamination, or changes in pH. Numerous sperm function assays provide information concerning subcellular compartments of the sperm including the plasma membrane, DNA, acrosome, and mitochondria. Data correlating these functional assays with fertility in the stallion are limited in most cases, with the exception of the sperm chromatin structure assay. Finally, the recent sequencing of the equine genome offers the possibility of both marker-assisted selection for fertility traits and more specific information about genetic mutations that may be associated with differing levels of fertility in the stallion.
Dynamical Effects of Convective Momentum Transports on Global Climate Simulations

Abstract Dynamical effects of convective momentum transports (CMT) on global climate simulations are investigated using the NCAR Community Climate Model version 3 (CCM3). To isolate the dynamical effects of the CMT, an experimental setup is proposed in which all physical parameterizations except for the deep convection scheme are replaced with idealized forcing. The CMT scheme is incorporated into the convection scheme to calculate the CMT forcing, which is used to force the momentum equations, while convective temperature and moisture tendencies are not passed into the model calculations in order to remove the physical feedback between convective heating and wind fields. Excluding the response of complex physical processes, the model with the experimental setup contains a complete dynamical core and the CMT forcing. Comparison between two sets of 5-yr simulations using this idealized general circulation model (GCM) shows that the Hadley circulation is enhanced when the CMT forcing is included, in agreeme...
Comment on the paper “The role of HBF4 in electro-catalysis: Arsenic contamination and anion adsorption” by A.L. Santos, R. Nagao, C.P. Oliveira, R.B. de Lima, H. Varela [J. Electroanal. Chem. 660 (2011) 147–152]

Abstract In their study on effects of arsenic in fluoroboric acid on formic acid oxidation, Santos et al. claim we make a number of claims and suggestions. We did not make these claims and suggestions.
Prediction of orientational phase transition in boron carbide

The assessed binary phase diagram of boron-carbon exhibits a single intrinsically disordered alloy phase designated “B4C” with rhombohedral symmetry occupying a broad composition range that falls just short of the nominal carbon content of 20%. As this composition range is nearly temperature independent, the phase diagram suggests a violation of the third law of thermodynamics, which typically requires compounds to achieve a definite stoichiometry at low temperatures. By means of first principles total energy calculations we predict the existence of two stoichiometric phases at T=0K: one of composition B4C with monoclinic symmetry; the other of composition B13C2 with rhombohedral symmetry. Using statistical mechanics to extend to finite temperatures, we demonstrate that the monoclinic phase reverts to the observed disordered nonstoichiometric rhombohedral phase above T=600K, along with a slight reduction on carbon content.
Edges and diffractive effects in Casimir energies

The prototypical Casimir effect arises when a scalar field is confined between parallel Dirichlet boundaries. We study corrections to this when the boundaries themselves have apertures and edges. We consider several geometries: a single plate with a slit in it, perpendicular plates separated by a gap, and two parallel plates, one of which has a long slit of large width, related to the case of one plate being semi-infinite. We develop a general formalism for studying such problems, based on the wave functional for the field in the gap between the plates. This formalism leads to a lower-dimensional theory defined on the open regions of the plates or boundaries. The Casimir energy is then given in terms of the determinant of the nonlocal differential operator which defines the lower-dimensional theory. We develop perturbative methods for computing these determinants. Our results are in good agreement with known results based on Monte Carlo simulations. The method is well suited to isolating the diffractive contributions to the Casimir energy.