cssi/SciSciGPT-SciSciNet huggingface dataset:
Deoxyribose-5-P aldolase: Subunit structure and composition of active site lysine region

Abstract Deoxyribose-5- P aldolase, a Class I aldolase, from Salmonella typhimurium has a molecular weight of 57,000 and is composed of two subunits of 28,500 molecular weight. Evidence from fingerprint analysis of tryptic digests and carboxypeptidase digestion suggests that the two subunits are identical. The COOH-terminal tyrosine residue which is removed by carboxypeptidase digestion appears to be necessary for catalytic activity but not for substrate binding. A tryptic peptide containing the “active site” lysyl residue modified by acetaldehyde has been purified and the following amino acid composition determined: (Ala 3 , Gly 3 , Thr 3 , Asx 2 , Ser, Ile, Phe, ∗N-Lys)-Lys.
Thiocyanate‐assisted demetallation of α,β,γ,δ‐tetra(p‐sulfophenyl)porphinatoindium(III) in aqueous media

The rate law for the demetallation of the title indium(III)-porphin complex in aqueous acidic thiocyanate media at 3.00M ionic strength was found to be of the form where [H4P2−] is the concentration of the diacid product formed, [InP]t is the total concentration of all forms of indium(III)-porphin complex present, and a and b are constants. The constant a is a pseudo-third-order rate constant with the value (0.057 ± 0.005)M−2 s−1 and b has the value 0.704M−2 at 50.5°C. If the mechanism for demetallation involves ringpuckering with the attachment of two H+ ions, then 1/b can be identified with the product K1K2 for the stepwise dissociation of two protons from two ring pyrrolic nitrogen atoms of H2InP−. In the sulfonated tetraphenylporphin used for these studies the ring pyrrolic nitrogen atoms seem to be the most probable sites for protonation. If this identification is correct, the value of 1.42 ± 0.13 found for the product K1K2 shows the enormous effect that the presence of the In3+ center has on the ionization constants of these two protons. That the kinetic studies show saturation effects with respect to proton addition to InP3− may result from the fact that In3+ sits about 0.6 A above the porphin ring.
TH‐D‐BRC‐07: Impact of Respiratory Biofeedback On Adaptively Sampled 4D‐CBCT Image Quality: Initial Experiences

Purpose: Linac‐mounted 4D‐Cone Beam CT(CBCT)imaging is an important tool for IGRT. Our protocol uses an in‐house built audio‐video (AV) biofeedback device to regularize patient respiration during 4D‐CBCT data acquisition. In this study, the impact of the respiratory stabilization on phase‐correlated 4D‐CBCT image quality is evaluated in our full field‐of‐view (FOV) 4D‐CBCT procedure using the Varian OBI and RPM respiratory monitoring system. Materials and methods: We have implemented a 4D‐CBCT imaging procedure with a 450.0 mm diameter FOV using adaptive acquisition time and projection sampling frequency. An AV respiratory biofeedback device consisting of a LCD visual and audio feedback channels was used. It provides the patient with a real‐time visual and auditory cues whenever the RPM deviates from the selected reference breathing trace. During the 8∼10 minute data acquisition, the patient was instructed to duplicate the reference trace as closely as possible both in terms of displacement and time. The acquired projections were sorted into 10 groups by the associated phase recorded by the RPM system. The effects of the AV biofeedback on the respiratory regularity were studied in terms of average cycle length, baseline variation and displacement. Subsequently, the corresponding 4D‐CBCT images were compared with different acquisition AV modes, such as free breathing, audio only and AV regularization. Results: The patient respiratory track presents larger variation in the free‐breathing data acquisition. The auditory instruction to the patient exhibits control of the displacement but a noticeable baseline drift through the time. The AV biofeedback device improves the reproducibility of respiratory pattern. Conclusion: Our results demonstrated that the AV biofeedback device improved the reproducibility of patient respiratory pattern in our 4D‐CBCT data acquisition. The image quality benefits from the improved projection consistency within an extended time span in every phase bin. Supported by PPG NIH P01 116602.
Karl Taylor Compton — Hoover medalist for 1950: Karl Taylor Compton: Scientist, educator, humanitarian

The Hoover Medal for 1950 was awarded to Karl Taylor Compton, Chairman of the Corporation of Massachusetts Institute of Technology. The medal is a joint award of the AIEE, The American Society of Mechanical Engineers, the American Institute of Mining and Metallurgical Engineers, and the American Society of Civil Engineers; Doctor Compton is the 12th recipient of this medal “to a fellow engineer for distinguished public service.”
A throughput/delay comparison: narrowband versus broadband wireless LAN's

A communication system in which some large number of portable notebook computers access a centrally-located base station by means of a shared, high-speed, radio-based LAN is considered. The delay and throughput performances of two alternative approaches are compared: one high-speed channel shared by all portable remotes versus several moderate-speed channels, each shared by a subset of portable units. In both cases, access to the intended services is impeded by contention for the medium and queueing for some shared server (processor or database). Both systems are modeled as closed-queueing networks, and expressions for system throughput and average request delay are obtained. Numerical results show that over a wide range of parameters, the system containing one high-speed channel outperforms the system containing several parallel medium-speed channels by less than 10%. >
Studying chert with electron-spin resonance

Abstract Archaeologists generally want to know how old their artifacts are and from where they came. Electron-spin resonance (ESR) is a tool for studying chert using radiation-induced signals analogous to those used for thermoluminescence (TL) and optically stimulated luminescence (OSL) dating. As a dating technique, it is well established for tooth enamel and shells, and initial studies suggest it may be possible to date quartz sediments. For this study, however, it is presently applicable only to heated chert. Work on samples from numerous sources has confirmed that heating chert is a complex process, and both the duration and temperature of heating must fall within certain ranges in order to obtain datable samples. Both Old World and New World material has been dated. Looking at these samples has also shown that variability among sources may permit proveniencing.
Saturation Technique Does Not Improve Cancer Detection as an Initial Prostate Biopsy Strategy

Purpose: We reported on the results of a sequential cohort study comparing office based saturation prostate biopsy to traditional 10-core sampling as an initial biopsy.Materials and Methods: Based on improved cancer detection of office based saturation prostate biopsy repeat biopsy, we adopted the technique as an initial biopsy strategy to improve cancer detection. Two surgeons performed 24-core saturation prostate biopsies in 139 patients undergoing initial biopsy under periprostatic local anesthesia. Indication for biopsy was an increased PSA of 2.5 ng/dl or greater in all patients. Results were compared to those of 87 patients who had previously undergone 10-core initial biopsies.Results: Cancer was detected in 62 of 139 patients (44.6%) who underwent saturation biopsy and in 45 of 87 patients (51.7%) who underwent 10-core biopsy (p >0.9). Breakdown by PSA level failed to show benefit to the saturation technique for any degree PSA increase. Men with PSA 2.5 to 9.9 ng/dl were found to have cancer in 53 ...
Crystallization Pressure of Salts in Stone and Concrete

Pressure by crystallizing salts against pore walls has caused disruption of rock, stone, and concrete, both in urban and desert environments. The Van9t Hoff-type equation for osmosis, as modified by Correns, is the basis for theoretical calculations of salt pressures. Under ideal conditions, halite can exert up to 650 atm pressure when it is oversaturated by a factor of 2. Air pollution, saline ground waters, and street salting in winter readily supply enough salt to inflict severe damage.
Two Components of Actin-based Retrograde Flow in Sea Urchin Coelomocytes

Sea urchin coelomocytes represent an excellent experimental model system for studying retrograde flow. Their extreme flatness allows for excellent microscopic visualization. Their discoid shape provides a radially symmetric geometry, which simplifies analysis of the flow pattern. Finally, the nonmotile nature of the cells allows for the retrograde flow to be analyzed in the absence of cell translocation. In this study we have begun an analysis of the retrograde flow mechanism by characterizing its kinetic and structural properties. The supramolecular organization of actin and myosin II was investigated using light and electron microscopic methods. Light microscopic immunolocalization was performed with anti-actin and anti-sea urchin egg myosin II antibodies, whereas transmission electron microscopy was performed on platinum replicas of critical point-dried and rotary-shadowed cytoskeletons. Coelomocytes contain a dense cortical actin network, which feeds into an extensive array of radial bundles in the interior. These actin bundles terminate in a perinuclear region, which contains a ring of myosin II bipolar minifilaments. Retrograde flow was arrested either by interfering with actin polymerization or by inhibiting myosin II function, but the pathway by which the flow was blocked was different for the two kinds of inhibitory treatments. Inhibition of actin polymerization with cytochalasin D caused the actin cytoskeleton to separate from the cell margin and undergo a finite retrograde retraction. In contrast, inhibition of myosin II function either with the wide-spectrum protein kinase inhibitor staurosporine or the myosin light chain kinase‐specific inhibitor KT5926 stopped flow in the cell center, whereas normal retrograde flow continued at the cell periphery. These differential results suggest that the mechanism of retrograde flow has two, spatially segregated components. We propose a “push‐pull” mechanism in which actin polymerization drives flow at the cell periphery, whereas myosin II provides the tension on the actin cytoskeleton necessary for flow in the cell interior.
Khan academy gamifies computer science

Gamification is the buzzword for adding gaming elements such as points or badges to learning experiences to make them more engaging and to increase motivation. In this paper we explore how Khan Academy has incorporated gaming elements into its CS learning platform. By mapping the literature on motivational processes to popular games we critically analyze how successful Khan Academy is at gamifying their site.
Risk Factors for Enamel Fluorosis in Optimally Fluoridated Children Born after the US Manufacturers' Decision to Reduce the Fluoride Concentration of Infant Formula

This case-control study investigated risk factors for enamel fluorosis in optimally fluoridated children, born after the US infant formula industry voluntarily reduced the fluoride content of their products. Analysis was performed on 233 children, aged 10-14 years. Case-control status was determined using the Fluorosis Risk Index (FRI). Risk factor exposure was ascertained via a mailed questionnaire. Logistic regression analyses revealed a strong association between mild-to-moderate enamel fluorosis on early forming (FRI classification I) enamel surfaces and both fluoride supplement use (odds ratio (OR)=5.95, 95% confidence interval (CI) 1.06-33.53), and early fluoride toothpaste use (OR=6.35, 95% CI 1.21-33.40). The authors found a suggestive, but nonsignificant, association between fluorosis on these enamel surfaces and infant formula in the form of powdered concentrate (OR=4.33, 95% CI 0.73-25.66). There was a strong association between mild-to-moderate fluorosis on later forming (FRI classification II) enamel surfaces and infant formula use in the form of powdered concentrate (OR=10.77, 95% CI 1.89-61.25), fluoride supplement use (OR=10.83, 95% CI 1.90-61.55), and early fluoride toothpaste use (OR=8.37, 95% CI 1.68-41.72). No association was observed between the use of ready to feed infant formula and enamel fluorosis.
Comparison of a Barotropic Blocking Theory with Observation

Abstract In an effort to explain observed blocking phenomena, the work of Charney and DeVore (1979) and Hart (1979) has been extended to incorporate observed zonal topography in a barotropic nonlinear channel model. Multiple stationary equilibria are obtained, one of which, for an appropriate forcing, corresponds exactly to the “normal” winter flow predicted by Charney and Eliassen (1949) from the linearized version of the model. When this forcing is applied in the nonlinear model, other equilibria, related to resonances with the wevenumber 2 and 3 Fourier components of the zonal topography, occur. Wavenumber 1 and 4 resonances could also have occurred with slight modifications of the model. For comparison with observation, semi-objective criteria are adopted for identifying blocking events from daily 500 mb observations of 15 consecutive winter seasons. Following Dole (1979), we demand that there exist sufficiently large geopotential height anomalies for a sufficient length of time. Numerical values of t...
Activating and inactivating mutations of the alpha subunit of Gi2 protein have opposite effects on proliferation of NIH 3T3 cells.

Abstract Previous studies have demonstrated that mutations of highly conserved residues in the alpha subunit of Gs (alpha s) can inhibit either the intrinsic GTPase activity (glutamine-227 to leucine, Q227L) or the ability of the protein to be activated by GTP (glycine-226 to alanine, G226A). We stably transfected NIH 3T3 cells with cDNAs encoding Gi2 alpha subunit (alpha i2) containing either wild-type sequence or the homologous mutations Q205L and G204A. High expression of wild-type alpha i2, Q205L alpha i2, and G204A alpha i2 was confirmed in transfected cells by immunoblot analysis. The overexpression of all three alpha i2 proteins was accompanied by an increase in beta-subunit expression. Q205L alpha i2 was a poor substrate for ADP-ribosylation by pertussis toxin as compared with wild-type alpha i2. Expression of Q205L alpha i2 markedly decreased forskolin- or cholera toxin-stimulated intracellular cAMP levels in intact cells, confirming the constitutively activated state of the protein. In contrast, G204A alpha i2 increased intracellular cAMP and was resistant to guanosine 5'-[gamma-thio]triphosphate-induced inhibition of ADP-ribosylation by pertussis toxin, as expected for an inactive alpha i2. Transfection of wild-type, Q205L, or G204A alpha i2 cDNA did not induce focus formation of NIH 3T3 cells. However, overexpression of Q205L alpha i2 induced a decreased serum requirement, a reduced doubling time, and an 8- to 10-fold increase in [3H]thymidine incorporation. Q205L alpha i2 cells formed small colonies in soft agar, demonstrating some degree of anchorage-independent proliferation. Expression of G204A alpha i2 slowed the growth of NIH 3T3 cells. We conclude that alpha i2 plays an important role in regulation of fibroblast growth.
The prelimbic cortex and subthalamic nucleus contribute to cue-guided behavioral switching

Frontal cortex-basal ganglia circuitry supports behavioral switching when a change in outcome information is used to adapt response patterns. Less is known about whether specific frontal cortex-basal ganglia circuitry supports behavioral switching when cues signal that a change in response patterns should occur. The present experiments investigated whether the prelimbic cortex and subthalamic nucleus in male Long-Evans rats supports cue-guided switching in a conditional discrimination test. Rats learned in a cross-maze that a start arm cue (black or white) signaled which of two maze arms to enter for a food reward. The cue was switched every 3-6 trials. Baclofen and muscimol infused into the prelimbic cortex significantly impaired performance by increasing switch trial errors, as well as trials immediately following a switch trial (perseveration) and after initially making a correct switch (maintenance error). NMDA receptor blockade in the subthalamic nucleus significantly impaired performance by increasing switch errors and perseveration. Contralateral disconnection of these areas significantly reduced conditional discrimination performance by increasing switch and perseverative errors. These findings suggest that the prelimbic area and subthalamic nucleus support the use of cue information to facilitate an initial switch away from a previously relevant response pattern.
Regelation, Surface Diffusion, and Ice Sintering

The freezing together of ice particles when they are brought into contact, originally described by Faraday and called regelation, is shown to occur not only at the freezing point, but also at temperatures as low as —25°C. It is shown that pressure melting is not essential to the process, nor is the presence of any unique liquid film. The welding together of ice particles occurs as a result of surface diffusion, as indicated by the time dependence and particle size dependence for the process. Surface diffusion of H20 molecules over an ice surface is found to be rapid. Equations for the kinetics of the process are closely related to those derived for sintering phenomena, but a quantitative derivation of the surface diffusion coefficient is not obtained.
Environmental exposure and mitochondrial epigenetics: study design and analytical challenges

The environment can influence human health and disease in many harmful ways. Many epidemiological studies have been conducted with the aim of elucidating the association between environmental exposure and human disease at the molecular and pathological levels, and such associations can often be through induced epigenetic changes. One such mechanism for this is through environmental factors increasing oxidative stress in the cell, and this stress can subsequently lead to alterations in DNA molecules. The two cellular organelles that contain DNA are the nucleus and mitochondria, and the latter are particularly sensitive to oxidative stress, with mitochondrial functions often disrupted by increased stress. There has been a substantial increase over the past decade in the number of epigenetic studies investigating the impact of environmental exposures upon genomic DNA, but to date there has been insufficient attention paid to the impact upon mitochondrial epigenetics in studying human disease with exposure to environment. Here, in this review, we will discuss mitochondrial epigenetics with regard to epidemiological studies, with particular consideration given to study design and analytical challenges. Furthermore, we suggest future directions and perspectives in the field of mitochondrial epigenetic epidemiological studies.
Modulation of trained and extinguished stimuli by facilitators and inhibitors

Pigeon subjects received training of a diffuse stimulus as either a conditioned inhibitor or a conditioned facilitator of a keylight signal for food. The ability of these diffuse stimuli to modulate responding was then assessed with two other keylights that were undergoing discrimination reversal. At a point where responding was equivalent for the two targets, the modulators had a greater impact on the target undergoing extinction than on the target undergoing acquisition. These results have implications for the nature of modulation and extinction.
Constrained Clipping for Crest Factor Reduction in OFDM

In this paper, we propose a constrained clipping method for reducing the peak to average power ratio (PAR) or crest factor of an orthogonal frequency division multiplexing (OFDM) signal. This is a transmitter-side processing technique that does not impose any modification at the receiver. Specifically, constrained clipping achieves PAR reduction while simultaneously satisfying spectral mask and error vector magnitude (EVM) constraints which are specified by most modern communications standards. Our proposed constrained clipping method consists of two independent processing units, one to satisfy the in-band EVM constraint and the other to satisfy the out-of-band spectral constraint. Achievable PAR reduction results vary depending on the particular standards' requirements, but we show that by using constrained clipping on a QPSK WiMax signal with 256 subcarriers, a 4.5 dB PAR reduction at the 10-2 complementary cumulative distribution function (CCDF) level can be obtained
Intrathoracic cystic hygroma: A report of three cases

Cystic hygromas are relatively uncommon benign tumors of the lymphatic system. The lesions frequently are apparent at birth, and more than 90% are detected before the end of the second year of life. Most commonly, cystic hygroma presents as a soft tissue mass in the posterior triangle of the neck, and only rarely does it extend into the mediastinum. Isolated intrathoracic hygromas are exceedingly rare and have been reported infrequently among children. Herein the authors review three cases of intrathoracic cystic hygroma, spanning a period of 30 years at their institution.
Effects of ooplasm transfer on paternal genome function in mice

background: The ooplasm plays a central role in forming the paternal pronucleus, and subsequently in regulating the expression of paternally inherited chromosomes. Previous studies in mice have revealed genetic differences in paternal genome processing by ooplasm of different genotypes. Ooplasm donation coupled to intracytoplasmic sperm injection (ICSI) has been used in human assisted reproductive technology (ART). This procedure exposes the developing paternal pronucleus to ‘foreign’ ooplasm, which may direct aberrant epigenetic processing. The potential effects of the foreign ooplasm on epigenetic information in the paternal pronucleus are unknown; however, some human progeny from ooplasm donation procedures display abnormalities. methods: In this study, we employed inter-genotype ooplasm transfer followed by ICSI using two mouse strains, C57BL/6 and DBA/2, to explore the influence of foreign ooplasm on paternal pronucleus function. In order to assay for effects on the paternal genome without masking effects of the maternal genome, we examined ooplasm effects in diploid androgenones, which are produced by pronuclear transfer to contain exclusively two paternal sets of chromosomes, in combination with ICSI. results: There was no significant effect of intra-strain ooplasm transfer among androgenones made with either C57BL/6 or DBA/2 oocytes. There was a significant negative effect on androgenone blastocyst development with inter-genotype transfer (10% volume) of DBA/2 ooplasm to C57BL/6 oocytes (P , 0.05). The reciprocal inter-genotype ooplasm transfer had no significant effect. conclusions: Thus, inter-genotype ooplasm transfer in conjunction with ICSI can alter the function of the paternal genome. However, the effect of foreign ooplasm is restricted to a negative effect, with no evidence of a positive effect. This study provides important new information about the possible consequences of ooplasm donation in human ART.
CHARACTERIZATION OF BEAKED WHALE (ZIPHIIDAE) AND SPERM WHALE (PHYSETER MACROCEPHALUS) SUMMER HABITAT IN SHELF‐EDGE AND DEEPER WATERS OFF THE NORTHEAST U. S.

Sperm whales (Physeter macrocephalus) and beaked whales (Mesoplodon spp. and Ziphius cavirostris) are deep-diving cetaceans that frequent shelf-edge and Gulf Stream waters off the northeast U. S. coast. Sighting data collected during seven summer (1990, 1991, 1993, and 1995–1998) shipboard surveys were analyzed using a geographic information system to determine habitat use based on bathymetric and oceanographic features. Although sighting rates were lower for beaked whales, both taxa occupied similar habitats. Beaked whales were concentrated at the colder shelf edge, whereas sperm whales were associated with warmer off-shelf water. Mean sighting rates for both taxa were higher in canyon features, but only beaked whale sighting rates were significantly different between canyon and non-canyon habitat (Wilcoxon signed rank test P= 0.007). Within the shared habitat, the two taxa were separated at fine-scale based on oceanographic features.
Heart rate variability in response to pain stimulus in VLBW infants followed longitudinally during NICU stay

The objective of this longitudinal study, conducted in a neonatal intensive care unit, was to characterize the response to pain of high-risk very low birth weight infants (< 1500 g) from 23 through 38 weeks post-menstrual age (PMA) by measuring heart rate variability (HRV). Heart period data were recorded before, during, and after a heel lanced or wrist venipunctured blood draw for routine clinical evaluation. Pain response to the blood draw procedure and age-related changes of HRV in low-frequency and high-frequency bands were modeled with linear mixed-effects models. HRV in both bands decreased during pain, followed by a recovery to near-baseline levels. Venipuncture and mechanical ventilation were factors that attenuated the HRV response to pain. HRV at the baseline increased with post-menstrual age but the growth rate of high-frequency power was reduced in mechanically ventilated infants. There was some evidence that low-frequency HRV response to pain improved with advancing PMA.
Choosing Optimal Control Structure for Run-to-Run Control - A Thin Film Example

This paper presents a case study for determining the optimal structure of the run-to-run control algorithm for thin film processes. Specifically, the expected process disturbance characteristics are used to determine the nature of the control strategy. Two examples of thin film processes are considered $(i) one involving a simple one-step deposition, and (ii) the other involving two deposition steps, with feedback only possible at the end of both the steps. This paper shows that a unified control structure is capable of handling multiple process types, which traditionally have used different controllers (in terms of their structure), especially in the presence of process shifts and drifts. Furthermore, the paper will also touch upon how the choice of the controller structure depends on the number of context dependent free parameters in the model
'Because he loves me': Husbands' involvement in maternal health in Guatemala

This study aimed to extend notions of male involvement to maternal health and to understand how Guatemalan men and women think about husband involvement in pregnancy, birth, and the postpartum period. Based on individual interviews and focus groups with men, women, and community health workers in two areas of rural Guatemala, this paper describes the pregnancy-related advice and assistance husbands give, and the reasons men are and are not involved in maternal health. Both men and women reported that male involvement in maternal health is relatively high, desirable, unique and affected by many factors. These include love, men's work demands, economic concerns and men's knowledge. The results help to fill broad gaps in understanding of male involvement in this aspect of family health and to amend stereotypes about husbands' relationship to maternal health and health care.
Recursive identification and tracking of parameters for linear and non-linear multivariable systems

The problem of identifying constant and variable parameters in multi-input, multi-output, linear and nonlinear systems is considered, using the maximum likelihood approach. An iterative algorithm, leading to recursive identification and tracking of the unknown parameters and the noise covariance matrix, is developed. Agile tracking, and accurate and unbiased identified parameters are obtained. Necessary conditions for a globally, asymptotically stable identification process are provided; the conditions proved to be useful and efficient. Among different cases studied, the stability derivatives of an aircraft were identified and some of the results are shown as examples.
Coexistence of atrioventricular block and Wolff-Parkinson-White syndrome in children

Coexistence of atrioventricular block and Wolff-Parkinson-White syndrome is uncommon, but may occur in children, particularly with certain congenital heart defects. Our study describes 5 children who had pre-excitation and underlying disturbance of atrioventricular conduction. All of these patients had structural heart defects, consisting of discordant atrioventricular connections in three, double inlet left ventricle in one, and a ventricular septal defect associated with straddling of the tricuspid valve in the other. In 4 of the patients, the presence of atrioventricular block was initially masked by the pre-excitation. When the conduction through an accessory pathway is lost, the child may be left with atrioventricular block, which is poorly tolerated in the setting of complex cardiac anatomy. Awareness of this association of Wolff-Parkinson-White syndrome and atrioventricular block is important in understanding the natural history and the management of children with congenital heart defects that are associated with tenuous atrioventricular conduction.
Subcellular curvature at the perimeter of micropatterned cells influences lamellipodial distribution and cell polarity

This paper employs substrates that are patterned with shapes having well-defined geometric cues to characterize the influence of curvature on the polarization of highly metastatic B16F10 rat melanoma cells. Substrates were patterned using microcontact printing to define adhesive islands of defined shape and size on a background that otherwise prevents cell adhesion. Cells adherent to these surfaces responded to local curvature at the perimeter of the adhesive islands; convex features promoted the assembly of lamellipodia and concave features promoted the assembly of stress filaments. Cells adherent to rectangular shapes displayed a polarized cytoskeleton that increased with the aspect ratio of the shapes. Shapes that combined local geometric cues, by way of concave or convex edges, with aspect ratio were used to understand the additive effects of shape on polarization. The dependence of cell polarity on shape was determined in the presence of small molecules that alter actomyosin contractility and revealed a stronger dependence on contractility for shapes having straight edges, in contrast to those having curved edges. This study demonstrates that the cytoskeleton modulates cell polarity in response to multiple geometric cues in the extracellular environment.
Ground adaptive standing controller for a powered transfemoral prosthesis

The scope of this work is the design and verification of a new standing controller for a powered knee and ankle prosthesis. The controller is based upon a finite-state impedance control approach previously developed by the authors. The controller provides a comprehensive standing behavior that incorporates ground adaptation for unlevel terrain. An amputee subject tested the controller with a powered prosthesis for a variety of standing conditions. Results indicate that the powered prosthesis can estimate the ground slope within ±1 degree over a range of ±15 degrees, and that it can provide appropriate joint impedances for standing on slopes within this range.
Environment management for hybrid user interfaces

As computers proliferate, becoming smaller, more mobile, more powerful and more diverse, how will the ways in which we interact with them change? In this article, we describe research in developing "hybrid user interfaces" that tie together the diverse displays and interaction devices that a user may encounter in a mobile, shared environment. Controlling such a dynamically changing, heterogeneous mix of computers is a problem that we refer to as "environment management". We sketch some ways in which publicizing semantic information about computational objects and tasks can make it possible to automate environment management operations, and we describe research testbeds we are developing within which to explore these ideas.
Temperature control of CMOS micromachined sensors

In this paper, we describe a methodology for temperature stabilization of CMOS micromachined sensors. Temperature stabilization of a z-axis accelerometer, fabricated in a 0.5 /spl mu/m Agilent CMOS process is demonstrated. The accelerometer motion is sensed by a vertical comb drive designed by controlling the rotor and stator curvature. The polysilicon layer of the CMOS process has been utilized for heating the device structure to a constant temperature, that is higher than the maximum ambient operating temperature. The capacitance detection circuits have temperature independent gain. The D.C. bias stability of the accelerometer improved from 1.9 G//spl deg/C, to 42 mG//spl deg/C, and the sensitivity stability improved from 60% to 18% over a temperature of 70/spl deg/C after temperature control.
Bovine Lymphocyte Antigen Class II Alleles as Risk Factors for High Somatic Cell Counts in Milk of Lactating Dairy Cows

Lactating Holstein cows (n = 1100) from 93 dairy herds in Iowa, Wisconsin, Minnesota, and Illinois were genotyped at the bovine lymphocyte antigen DRB3.2 locus by a genotyping system that used polymerase chain reaction and restriction fragment length polymorphisms. Milk samples were obtained after routine processing at a Dairy Herd Improvement Association facility and returned to the National Animal Disease Center for DNA extraction. Somatic cells were used to classify cows that had acutely elevated SCC (one test of SCC >500,000; group 1), or chronically elevated SCC (three consecutive tests of SCC >300,000 or two consecutive tests of >500,000; group 2), or that were eligible as controls. For each cow in groups 1 and 2, controls were selected that were matched for breed, lactation, herd, and days in lactation (±60 d). A conditional model for stepwise logistic regression was used to determine the relative odds for the 10 alleles with a frequency >3%. No significant associations were observed when the 292 cows in group 2 were compared with their 292 controls. Allele *16 was associated with an increased risk of disease for cows classified with an acute SCC (258 cases and 258 controls). This study has identified DRB3.2*16 as a potential risk factor for acute intramammary infection and established the use of Dairy Herd Improvement Association milk samples as a source of DNA that is useful for genetic epidemiologic studies.
Dynamic formation algorithms and experiments

We explore and implement a new decentralized strategy for dynamically changing formation control. The purpose of this control strategy is for groups of mobile robots to adapt the shape and size of their formation. In this paper, we present both the control algorithms and experimental results. Based on these results this strategy is an effective method for controlling the formation of multiple mobile robots.
Low-latency nonlinear fiber-based approach for data encryption and anti-jamming in optical network

All-optical encryption and anti-jamming have been experimentally demonstrated in an optical CDMA system using four-wave mixing in a 32-cm highly-nonlinear bismuth-oxide fiber. The scheme provides a high-speed, compact, and low latency approach for network security.
The effect of epidermal growth factor on differentiation of isolated enterocytes after small bowel resection

Abstract Background/Purpose: In previous studies using mucosal scrapings or whole-bowel homogenates, epidermal growth factor (EGF) augments adaptation after massive small bowel resection (SBR). The purpose of this study was to determine directly the effect of adaptation and EGF on enterocyte differentiation using an explicit enterocyte cell population. Methods: Male ICR mice underwent 50% proximal SBR or sham (bowel transection-reanastomosis) and were selected randomly to either orogastric saline or EGF (50 μg/kg/d). After 3 days, enterocytes were isolated from the remnant ileum by mechanical vibration and assayed for DNA and protein content as well as sucrase and alkaline phosphatase (AlkP) activity. Results: Ileal wet weight, enterocyte protein, and DNA content were increased significantly after SBR and boosted even further with EGF. When normalized for protein, SBR caused an increase in AlkP and sucrase activity, and EGF treatment caused AlkP and sucrase activity to return to baseline. Conclusions: EGF enhances adaptation; however, when normalized for protein, the activity of two enterocyte-specific enzymes was not significantly altered by EGF. This analysis of an explicit enterocyte population supports the notion that the beneficial effects of EGF are more likely caused by increased numbers of enterocytes rather than an increase in the functional activity of each individual cell.
Mineralogy of eroded sediments derived from highly weathered Ultisols of central Alabama

Coarse-textured surface horizons are common in highly weathered southeastern US coastal plain soils. These soils have historically been managed under conventional tillage practices, but conservation tillage management practices are increasing. Although clay (<2 �m) contents are low in these surface horizons (typically < 1 0 0gk g −1 ), the reactive nature of this fraction tends to play a dominant role in colloidal facilitated pollutant transport. Studies have suggested that enrichment of certain minerals occurs in transported sediments, thus, we evaluated sediment size and the mineralogical partitioning of clay minerals of soil versus runoff sediment under simulated rainfall. In addition, because water dispersible clay (WDC) has been shown to be correlated with soil erodibility, we evaluated WDC differences as a function of tillage practices. Plots were established at a site in the upper coastal plain of central Alabama, where soils classified as coarse-loamy, siliceous, subactive, thermic Plinthic Paleudults and Typic Hapludults (FAO-Acrisols). Surface tillage treatments were established in 1988, and included conventional tillage (CT) versus no surface tillage (NT) treatments, with crop residue remaining or removed, and with or without paratilling (non-inversion subsoiling). Within these plots, simulated rainfall (target intensity = 50 mm h −1 for 2 h) was applied to replicated 1 m × 1 m areas, and runoff and sediment were collected. Mineralogical analyses of soils and sediment were conducted using thermogravimetric analysis (TGA) and X-ray diffraction (XRD) techniques. WDC quantities were highly correlated with percent soil organic carbon (SOC) (r 2 = 0.76), which was a function of tillage treatment. Although no differences in the mineralogy of the <2 �m sediment were observed between tillage treatments, runoff sediments (<2 �m) were enriched in quartz (qtz) and relatively depleted with kaolinite compared to in situ soils. These findings will facilitate development of mechanistic models that predict sediment attached losses of nutrients and pesticides. Published by Elsevier Science B.V.
Biosynthetic pathway for producing the sex pheromone component (Z,E)-9,12-tetradecadienyl acetate in moths involves a delta 12 desaturase.

Sex pheromones are used by insects as a form of chemical communication for the purpose of attracting conspecific mates. Female moths Cadra cautella and Spodoptera exigua use the diene (Z,E)-9,12-tetradecadienyl acetate as the major pheromone component. Biosynthesis of this pheromone component was demonstrated to occur through Δ 11 desaturation of hexadecanoic acid (palmitate) to produce (Z)-11-hexadecenoic acid which is then chain-shortened to (Z)-9-tetradecenoic acid. A unique Δ 12 desaturase uses the (Z)-9-tetradecenoic acid to produce (Z,E)-9,12-tetradecenoic acid which is reduced and acetylated to form the acetate ester pheromone component. Both moths also use a pheromonotropic peptide to stimulate pheromone biosynthesis.
PROPORTION OF FEATHERS AT DIFFERENT BODY LOCATIONS OF WHITE LEGHORN PULLETS

Abstract Feathers are a by-product of the poultry industry. They may be found in use in various ways, and feathers from different areas of the body may be used for different purposes. Feathers account for 4- 9 percent of the empty live weight of chickens according to Winter and Funk (1960) and Card (1961). Jull (1938) gave the percentage as about 7 percent of the live weight. Latimer and Pedersen (1929) reported that chickens with an average body weight of 1096.8 -+- 12.3 grams had an average weight of 84.5 ± 1.3 grams of feathers. The chickens were of different ages and no breed was given. No references were found as to the percent feathers of different areas were of the total feather weight or of the body weight.…
Structural Change, Capital Investment and Productivity in the Food Processing Industry

Investment in new technology affects structural change and economic performance through its effect on capital and input composition. This is particularly important for capital-intensive industries such as food processing, which lack short-run flexibility due to adjustment costs. This study considers the impacts of capital quasi-fixity on capital and noncapital input decisions made in the U.S. Food and Kindred Products industry from 1965 to 1991. A cost-based production theory model is used to evaluate investment motivations for three capital components. Productivity growth accompanying changing input patterns is then discussed, focusing on capital and farm input demand.
New insights into the pathogenesis, diagnosis and treatment of human T-cell leukemia virus type 1-induced disease

It has been over 25 years since the discovery of human T-cell leukemia virus type 1 (HTLV-1); however, the exact sequence of events that occur during primary infection, clinical latency or the development of disease remains unresolved. The advances in molecular virology and neuroimmunology have contributed significantly to our understanding of HTLV-1 pathogenesis, but also uncovered the complexity of the virus–host interaction both in the peripheral blood and the CNS. Here, we overview the general pathologic features of HTLV-1, molecular mechanisms of oncogenic transformation and characteristics of the host immune response during the associated neuroinflammatory process. We also discuss both current and new approaches in the diagnosis and therapy of HTLV-1 associated diseases – adult T-cell leukemia and HTLV-1-associated myelopathy/tropical spastic paraparesis. Finally, potentially important emerging areas of research that may have an impact on our understanding of the pathogenic mechanism have been brief...
Quality of Care and Ischemic Stroke Risk After Hospitalization for Transient Ischemic Attack Findings From Get With The Guidelines-Stroke

Background—Patients with transient ischemic attack (TIA) are at increased risk for ischemic stroke. We derived a prediction rule for 1-year ischemic stroke risk post-TIA, examining estimated risk, receipt of inpatient quality of care measures for TIA, and the presence or absence of stroke at 1 year post discharge. Methods and Results—We linked 67 892 TIA Get With The Guidelines-Stroke patients >65 years (2003–2008) to Medicare inpatient claims to obtain longitudinal outcomes. Using Cox proportional hazards modeling in a split sample, we identified baseline demographics and clinical characteristics associated with ischemic stroke admission during the year post-TIA, and developed a Get With The Guidelines Ischemic Stroke after TIA Risk Score; performance was examined in the validation sample. Quality of care was estimated by a global defect-free care measure, and individual performance measures within estimated risk score quintiles. The overall hospital admission rate for ischemic stroke during the year pos...
The Effect of Specific Welfare Policies on Poverty

This paper uses monthly SIPP data from 1988 through 2002 and monthly state-level policy data to measure the effects of specific policies on the deep poverty and poverty rates of ever-single mothers and children of ever-single mothers. The 19 specific policies included in the model are grounded in a conceptual framework. More lenient eligibility requirements for welfare receipt and more generous financial incentives to work generally reduce deep poverty, as hypothesized. Welfare time limits are hypothesized to have ambiguous effects on poverty and our results suggest that some stricter time limit policies may decrease deep poverty and poverty rates.
Identifying potential bottlenecks in production systems using dual prices from a mathematical programming model

The importance of identifying bottlenecks in production systems for effective production control and continuous improvement is well recognised. A useful definition of a bottleneck is the station to whose performance the performance of the overall production system is most sensitive. However, obtaining accurate estimates of the impact of changes in a given station's performance on the performance of a production system is often difficult. This paper uses the dual prices associated with production resources in a production planning model to support the identification of bottlenecks as the product mix in the system changes over time. The planning model considers queueing behaviour at production resources using non-linear clearing functions. Relationships between the dual prices of different resources are derived, and the bottleneck information obtained is compared to that from a model that does not consider queueing behaviour.
New method for obtaining optimal polygonal approximations to solve the min- $$\varepsilon$$ ε problem

A new method for obtaining optimal polygonal approximations in closed curves is proposed. The new method uses the suboptimal method proposed by Pikaz and an improved version of the optimal method proposed by Salotti. Firstly, the Pikaz’s method obtains a suboptimal polygonal approximation and then the improved Salotti’s method is used for obtaining many local optimal polygonal approximations with a prefixed starting point. The error value obtained in each polygonal approximation is used as value of pruning to obtain the next polygonal approximation. In order to select the starting point used by the Salotti’s method, five procedures have been tested. Tests have shown that by obtaining a small number of polygonal approximations, global optimal polygonal approximation is calculated. The results show that the computation time is significantly reduced, compared with existing methods.
Patients crossing our borders: an ethical or economic conundrum?

I would like to thank the Members of the Western Trauma Association for the opportunity to serve as your President for the past year. There are many reasons why I enjoy being part of this organization. The cultivation of lasting friendships, the camaraderie and collegiality of the scientific meetings and the family atmosphere that has been created make the Western Trauma Association one of the best kept secrets in American surgery. The memories that I have of our annual meetings often make me reflect on the priorities that we set for our careers. Skiing with my children throughout the West and Canada, having my sons be on a first name basis with leaders in the field of trauma and watching them take off with the “pack” not caring whether I was present or not was sometimes painful, but always gratifying. The title of my presidential address came from a communication I had with one of my former hospital administrators. He approached me about a critically ill trauma patient that I was caring for in the intensive care unit, saying, “Dr. Petersen, what are we going to do about the ethical conundrum concerning Case JC?” He did not say, “Mr. JC” or “your patient JC,” just “Case JC.”