cssi/SciSciGPT-SciSciNet huggingface dataset:
Retrovirally mediated telomerase immortalization of neural progenitor cells

Traditional methods of generating immortalized lines of both somatic cells and their progenitors have relied on the use of oncogenes. However, the resulting lines are typically anaplastic in vitro and tumorigenic in vivo, and hence of limited utility. The overexpression of telomerase, as mediated by the induced overexpression of human telomerase reverse transcriptase (hTERT), has permitted the generation of stable, non-oncogenic lines of a variety of cell types. This strategy for immortalization has found special utility in the central nervous system, as few stable lines are available for the study of either human neural progenitor cells, or of neurons or glia of restricted phenotype. We describe the use of retroviral hTERT overexpression for generating lines of immortalized human neural progenitor cells, whose neuronal progeny are phenotypically restricted, post-mitotic and functionally competent. Although we focus here on telomerase immortalization of spinal neural progenitors, this is a broadly applicable protocol for using hTERT to immortalize human fetal neural progenitors of any pre-selected phenotype and for characterizing the cell lines thereby generated.
CHOOSING BETWEEN AN ADDITIVE AND A MULTIPLICATIVE MODEL OF EXPERIMENTAL EFFECTS

An experiment is carried out, and the question is whether the experimental effect is additive or multiplicative. This paper suggests a decision-theoretic approach to this problem of model choice when the underlying population distribution is normal.
Multiple damage identification on a wind turbine blade using a structural neural system

A large number of sensors are required to perform real-time structural health monitoring (SHM) to detect acoustic emissions (AE) produced by damage growth on large complicated structures. This requires a large number of high sampling rate data acquisition channels to analyze high frequency signals. To overcome the cost and complexity of having such a large data acquisition system, a structural neural system (SNS) was developed. The SNS reduces the required number of data acquisition channels and predicts the location of damage within a sensor grid. The sensor grid uses interconnected sensor nodes to form continuous sensors. The combination of continuous sensors and the biomimetic parallel processing of the SNS tremendously reduce the complexity of SHM. A wave simulation algorithm (WSA) was developed to understand the flexural wave propagation in composite structures and to utilize the code for developing the SNS. Simulation of AE responses in a plate and comparison with experimental results are shown in the paper. The SNS was recently tested by a team of researchers from University of Cincinnati and North Carolina A&T State University during a quasi-static proof test of a 9 meter long wind turbine blade at the National Renewable Energy Laboratory (NREL) test facility in Golden, Colorado. Twelve piezoelectric sensor nodes were used to form four continuous sensors to monitor the condition of the blade during the test. The four continuous sensors are used as inputs to the SNS. There are only two analog output channels of the SNS, and these signals are digitized and analyzed in a computer to detect damage. In the test of the wind turbine blade, multiple damages were identified and later verified by sectioning of the blade. The results of damage identification using the SNS during this proof test will be shown in this paper. Overall, the SNS is very sensitive and can detect damage on complex structures with ribs, joints, and different materials, and the system relatively inexpensive and simple to implement on large structures.
Chronic insulin therapy reduces adipose tissue macrophage content in LDL-receptor-deficient mice.

Aims/hypothesis Insulin has anti-inflammatory effects in short-term experiments. However, the effects of chronic insulin administration on inflammation are unknown. We hypothesised that chronic insulin administration would beneficially alter adipose tissue inflammation and several circulating inflammatory markers.
Printer banding estimation using-the Generalized Spectrum

This paper compares multi-step algorithms for estimating banding arameters of a harmonic signature model. The algorithms are based on two different spectral measures, the power spectrum (PS) and the collapsed average (CA) of the generalized spectrum. The generalized spectrum has superior noise reduction properties and is applied for the first time to this application. Monte Carlo simulations compare estimation performances of profile (or coherent) averaging and non-coherent spatial averaging for estimating banding parameters in grain noise. Results demonstrate that profile averaging has superior noise reduction properties, but is less flexible in applications with irregular banding patterns. The PS-based methods result in lower fundamental frequency estimation error and greater peak height stability for low SNR values, with coherent averaging being significantly superior to non-coherent averaging. The CA has the potential of simplifying the detection of multiple simultaneous banding patterns because its peaks are related to intra-harmonic distances; however, good CA estimation performance requires sufficiently regular harmonic phase patterns for the banding harmonics so as not to undergo reduction along with the noise. In addition to the simulations, the algorithms are applied to samples from inkjet and laser printers to demonstrate the ability of the harmonic signature model in separating banding from grain and other image artifacts. Good results from experimental data are demonstrated based on visual inspection of examples where banding and grain have been separated.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Off-resonance laser frequency stabilization using the Faraday effect.

We present a simple technique for stabilization of a laser frequency off resonance using the Faraday effect in a heated vapor cell with an applied magnetic field. In particular, we demonstrate stabilization of a 780nm laser detuned up to 14GHz from the Rb85D252S1/2F=2 to 52P3/2F′=3 transition. Control of the temperature of the vapor cell and the magnitude of the applied magnetic field allows locking ∼6–14GHz red and blue detuned from the atomic line. We obtain an rms fluctuation of 7MHz over 1h without stabilization of the cell temperature or magnetic field.
Current concepts on the pathophysiology and management of recurrent ankle sprains and chronic ankle instability

Lateral ankle sprains occur more than any other musculoskeletal injury in an athletic population. The greatest risk for an inversion ankle sprain is a history of a previous sprain. Recurring instability associated with subjective complaints of giving way is often termed chronic ankle instability (CAI). CAI has been associated with altered postural control, sensorimotor deficits, reduced physical activity, functional limitations, and long-term degeneration of the joint. Alterations, including muscle activity and changes in the kinematics of the lower extremity may predispose this population to continued instability at the joint and long term health issues. Common treatments include using external support, therapeutic modalities, and directed rehabilitation. Wearing ankle braces and performing balance training has been shown to reduce the risk of recurrent ankle sprains. Directed rehabilitation may improve function in patients with CAI. By identifying and minimizing dysfunction following ankle sprains, clinicians may improve the short-term and long-term function of this population.
The Move Toward Electronic Health Records

A multitude of projects are under way that support the transition to electronic health records, which enable the exchange of health information among healthcare-related parties while maintaining patient privacy and offering security protections.
Recurrent changes in colony morphology dependent on intracolony selection of prototrophs occurring in red yeast

Recurrent changes in colony morphology dependent on intracolony selection of prototrophs occurring in red yeast 1
State retention of medical school graduates.

State governments support medical schools in their states for various reasons. A major reason is the perception that graduates tend to practice in the state where they attend medical school. In a study reported here, the authors examined this assumption by investigating the experience of physicians currently active in medical practice. The entire population of active U.S. physicians who graduated from U.S. medical schools was examined, as well as four selected cohorts of U.S. medical school graduates, using the American Medical Associations' Physician Masterfile. The ability of states to retain their medical school graduates is related to physician characteristics (age, medical school, and practice specialty) as well as to state characteristics (population, physician-to-population ratio, and per capita income). The results indicate that, overall, the argument that states should support medical schools in order to ensure an adequate supply of physicians is less compelling than in the past, for reasons often beyond the control of the individual states.
Family Leisure and Social Support: Relations with Parenting Stress and Psychological Well-Being in Head Start Parents

The Parent Involvement component of Head Start has multiple goals that include supporting parents' personal development and promoting positive parenting experiences. However, little is known about how experiences such as social support and family leisure may be related to parental functioning, including psychological well-being and parenting stress. In this study of 103 Head Start parents, various aspects of positive parental functioning were related to increases in overall leisure time and leisure time spent with spouse for both mothers and fathers, to increase in leisure time with extended family for mothers, and to increase in leisure time with children for fathers. In addition, increase in social support, particularly informal social support, was related to positive parental functioning for fathers. These results suggest that opportunities for specific contexts of leisure and types of social support may have potential for promoting positive parenting and psychological well-being among Head Start parents.
The precipitating effect of methanol on viruses.

SummaryFive viruses (Eastern equine encephalomyelitis, MEF human poliomyelitis, mumps, influenza B, and Newcastle disease) were utilized in studying the precipitating effect on them of methanol. Optimal methanol concentrations and optimal pH for elution were determined for each virus and are tabulated (Table I). All of the viruses which were studied demonstrated a relationship between the pH of the elution fluid and solubility: as the pH was raised there was a corresponding increase in solubility of the virus. The methanol precipitation technic results in considerable loss of nitrogen from the virus suspension, but this loss does not appear to be at the expense of the virus.
Predicting faculty interest in student advising in the community college

The primary purpose of this study was to identify any significant relationships between a measure of faculty interest in counseling activities (PAICT) and nine selected student advising experiences. The research setting was a community college of 12,047 students. A stratified, random sample of full-time faculty was selected to complete the PAICT measure, and a cluster random sample of their students were used to obtain self-reported experiences of the advising activities. Only 11% of the variance was accounted for between the faculty PAICT scores and the self-reported advising experiences of their students. There was 17% of the variance accounted for between faculty PAICT scores and eight personal characteristics of their students. The findings indicate that the faculty interest in advising does not affect the way students are advised.
Low dose zymosan ameliorates both chronic and relapsing experimental autoimmune encephalomyelitis

Zymosan has previously been reported to have both pro-inflammatory and anti-inflammatory effects. Here we demonstrate that low dose zymosan prevented or reversed chronic and relapsing paralysis in EAE. In suppressing CNS autoimmune inflammation, zymosan not only regulated APC costimulator and MHC class II expression, but also promoted differentiation of regulatory T cells. Following adoptive transfer of zymosan-primed CD4+ T cells, recipient mice were protected from EAE. In contrast, a MAPK inhibitor and a blocker of β-glucan, reversed the effects of zymosan. These results demonstrate that zymosan may be a promising beneficial agent for Multiple Sclerosis (MS).
Molecular cloning of extremely thermostable esterase gene from hyperthermophilic archaeon Pyrococcus furiosus in Escherichia coli.

A genomic library of the hyperthermophilic archaeon Pyrococcus furiosus was constructed in Escherichia coli using pBluescript II SK(+) as a cloning vector. One positive clone exhibiting thermophilic ester-hydrolyzing activity was directly detected by an in situ plate assay using the chromogenic substrate 5-bromo-4-chloro-3-indolyl-acetate. The plasmid isolated from the clone contained a 3.8 kb HindIII fragment from P. furiosus. Expression of active thermostable esterase in E. coli was independent of isopropyl-β-d-thiogalactopyranoside, suggesting that the archaeal esterase gene was heterologously controlled by its own promoter sequence, not by the vector-located lac promoter. Assays of esterase activity in heat-treated extract of the recombinant E. coli showed the highest temperature optimum (100°C) and thermostability (a half-life of 50 min at 126°C) among esterases reported to date. ©1998 John Wiley & Sons, Inc. Biotechnol Bioeng 57: 624-629, 1998.
Radioactivities Produced by Proton Bombardment of Palladium

Proton bombardment of Pd produces the three known Ag periods of 2.3 min. (${\mathrm{Ag}}^{108}$), 25 min. and 8 days (${\mathrm{Ag}}^{106}$), and three new periods of 16.3 min. (+), 73 min. (+) and 45 days ($K$ capture). The latter are assigned tentatively to ${\mathrm{Ag}}^{102}$, ${\mathrm{Ag}}^{104}$, and ${\mathrm{Ag}}^{105}$, respectively. Excitation functions for the isomeric 25-min. and 8-day periods give $p\ensuremath{-}n$ thresholds of 3.8 and 3.9 Mev, respectively. The former agrees with the known positron spectrum of the short period. The higher threshold for the 8-day period indicates that this state lies above the 25-min. state. This activity is accompanied by probably three gamma-rays of which two of 0.62 and 1.06 Mev have been identified with a beta-ray spectrograph. Since no positrons accompany this activity it must decay mainly by $K$-electron capture to ${\mathrm{Pd}}^{106}$ rather than to the lower isomeric state. Four gamma-rays of about 0.29, 0.42, 0.50, and 0.69 Mev accompany the 45-day period.
Transition temperature and gap anisotropy of pure and impure superconductors

The algebraic structure of linearized Eliashberg theory atT=Tc is exploited to derive expressions for the anisotropic gapΔ(k, iω n ) and theTc-enhancement. These formulas are exact to second order in the anisotropy, and require as input the isotropic gapΔ(k, iω n ), the anisotropic spectral function α2F(k, Ω), and the impurity scattering rate 1/τ k . Approximate formulas based on a square well model are also given. The formulas for impurity effects are new and very simple.
Stellar evolution at high mass based on the Ledoux criterion for convection.

Theoretical evolutionary sequences of models for stars of 15 and 30 solar masses were computed from the zero-age main sequence to the end of core helium burning. During the earliest stages of core helium depletion, the envelope rapidly expands into the red-supergiant configuration. At 15 solar mass, a blue loop on the H-R diagram ensues if the initial metals abundance, initial helium abundance, or C-12 + alpha particle reaction rate is sufficiently large, or if the 3-alpha reaction rate is sufficiently small. These quantities affect the opacity of the base of the outer convection zone, the mass of the core, and the thermal properties of the core. The blue loop occurs abruptly and fully developed when the critical value of any of these quantities is exceeded, and the effective temperature range and fraction of the lifetime of core helium burning during the slow phase of the blue loop vary surprisingly little. At 30 solar mass no blue loop occurs for any reasonable set of input parameters.
Neonatal urinomas: Imaging considerations

Neonatal urinomas can be defined as encapsulated extravasations of urine occuring secondary to congenital obstructive uropathies. Since 1978, four patients with proven urinomas have been studied at the Medical University of South Carolina, three of which had posterior urethral valves and the fourth, a segmental ureteral atresia. They were classified into three major types; subcapsular, diffuse perirenal and localized perirenal. The radiologic and imaging appearances are demonstrated. We found the most efficacious approach for identification of neonatal urinomas to be renal ultrasound, voiding cystourethrography and the Tc-99 m DPTA renal scintigraphy.
The interaction of Δ9-tetrahydrocannabinol with cholinomimetic drugs in an agonist-antagonist paradigm

Abstract In rabbits, i.v. Δ9-tetrahydrocannabinol (Δ9-THC) at 0.5 mg/kg was challenged with i.v. arecoline (0.025 mg/kg), nicotine (0.02 mg/kg) or physostigmine (PHYSO, 0.05 mg/kg), and observations were made on quantified EEG and behavior. The cholinomimetics effectively reversed the cortical and hippocampal EEG alterations induced by Δ9-THC. Arecoline and PHYSO temporarily reversed the behavioral-sedative effects of Δ9-THC whereas the combination of Δ9-THC with nicotine produced behavioral collapse preceded by behavioral disturbance.
Mass productions of thin film silicon PV modules

Abstract Mass production technologies of a-Si single junction and a-Si/poly-Si hybrid modules with stable 8% and 10% efficiency were developed in the Shiga factory of Kaneka Corporation. Kaneka instituted Kaneka Solartech Corporation (KST) as a subsidiary company of 100% shareholder and invested 20 MW production plant in Toyooka City in 1999. There are fully automatic thin film fabrication equipments. KST started the manufacturing amorphous silicon PV modules in 1999 and those of hybrid type PV modules in 2001. The largest size glass substrates used for these modules are 95×98 cm and variable size of modules are being produced by cutting these large area base modules. Recent production yields are higher than 98%. Production technologies of a-Si, thin c-Si and solar cells, performances of modules, applications to the rooftop PV systems will be presented. We estimate the production cost of a-Si solar modules and a-Si/thin c-Si hybrid solar modules. The future business plan of our new type solar modules and our production lines will be discussed.
Deoxyadenylate-rich sequences in sea urchin DNA during early development.

Abstract Sea urchin ( Strongylocentrotus purpuratus ) DNAs from morula and blastula stage embryos and from sperm were examined, by hybridization to [ 3 H] polyuridylic acid, for the proportion of DNA sequences rich in deoxyadenylate. By this criterion, it was found that, relative to sperm DNA, morula DNA has 65% less deoxyadenylate-rich DNA. Blastula DNA has 1.7 times as much deoxyadenylate-rich sequence as does morula DNA. Fractionation of these DNAs on neutral and alkaline cesium chloride density gradients indicates that the differences in the deoxyadenylate-rich content of the DNAs pertains predominantly to main density band DNA. Fractionation on cesium salt gradients also obviates the possibility that the measured differences in the DNAs result from preferential loss of satellite DNA during isolation of bulk DNAs.
Questionnaires in Second Language Research: Construction, Administration, and Processing by DÖRNYEI, ZOLTÁN, with TATSUYA TAGUCHI.

A review of the book "Questionnaires in Second Language Research: Construction, Administration, and Processing," by Zoltan Dornyei and Tatsuya Taguchi is presented.
WIDENING THE RANGE OF SERVICES FOR THE HOMELESS MENTALLY ILL

The rapid emergence of homelessness as a social problem has resulted in the growth of a shelter-based service system. Although capable of providing basic support, this system appears unable to serve a diverse population of homeless mentally ill people. A strategy for reducing the gap between this population's needs and available assistance involves removing access barriers and strengthening service coordination at both the organization and client levels.
On a Presumed Omission in Kant's Derivation of the Categorical Imperative

A new book by Stephen Engstrom repeats a criticism of Bruce Aune's of Kant's derivation of the universalizability formula of the categorical imperative. The criticism is that Kant omitted at least one substantive premise in the derivation of the formula: ‘Act only on that maxim through which you can at the same time will that it become a universal law.’ The grounds for the formula that are given in the Groundwork of the Metaphysics of Morals, however, are said to support only a weaker requirement, namely, that a maxim conform to a universal law. Hence, Kant omits at least one necessary substantive premise of the derivation. This paper attempts to show that nothing substantive is omitted from the argument. It only needs two principles of inference that it is assumed add nothing substantive to the premises.
Inhibitory effects of a new neuroprotective diltiazem analogue, T-477, on cloned brain Ca2+ channels expressed in Xenopus oocytes

A new neuroprotective agent T-477 ((R)-(+)-2-(4-chlorophenyl)-2,3-dihydro-4-diethylaminoacetyl-4H-1, 4-benzothiazine) and diltiazem are similar in chemical structures but they show different biological properties. To investigate the properties that differentiate T-477 from diltiazem, we examined the effects of the compounds on a cardiac L-type and brain non-L-type Ca2+ channels expressed in Xenopus oocytes. Cardiac L-type currents were inhibited by Ca2+ channel antagonists with an order of potency; PN200-110 isradipine > > diltiazem > T-477. Brain BI (class A)-, BII (class E)- and BIII (class B)-type Ca2+ channel currents were inhibited by T-477 with an IC50 of 45, 74 and 59 microM, respectively, whereas diltiazem barely inhibited the brain non-L-type channels and PN200-110 had no effect. T-477 caused a marked use- and frequency-dependent block of BI Ca2+ channel currents, as demonstrated by a cumulative increase of the block during a train of depolarizing pulses, which seemed to be due to a slow repriming of the drug-bound channels from inactivation. These results suggest that T-477 exerts neuroprotection of brain neurons from ischemic neuronal damage through its inhibitory action on brain Ca2+ channels that differentiates T-477 from cardiac L-type channel blockers such as diltiazem and PN200-110.
Far infrared absorption in bulk amorphous red phosphorous

Abstract Far infrared absorption measurements have been performed above 30 cm −1 in bulk amorphous red P at 300 K. A number of low frequency spectral features are observed that are not present in the corresponding bulk amorphous As spectrum. Deep minima observed at 163 and 320 cm −1 in α(ω) and in the Raman spectra suggest that the phonon density of states is essentially divided into 3 bands. A calculation of the mean effective charge of the bands indicates weak coupling to the lowest frequency band. A comparison with the results in a -As suggests a less rapid frequency variation in the infrared coupling parameter at low frequencies in a - P .
Continuum model for simultaneous chemical reactions and mass transport in hydrothermal systems

Abstract A time-space continuum model for transport of hydrothermal fluids in porous media is presented which provides for simultaneous, reversible and irreversible chemical reactions involving liquids, gases and minerals. Homogeneous and heterogeneous reactions are incorporated in the model in a similar fashion through source/sink terms added to the continuity equation. The model provides for moving reaction fronts through surfaces of discontinuity across which occur jump discontinuities in the various field variables satisfying generalized Rankine-Hugoniot relations. Reversible reactions including aqueous complexing, oxidation-reduction reactions, mineral precipitation and dissolution reactions and adsorption are explicitly accounted for by imposing chemical equilibrium constraints in the form of mass action equations on the transport equations. This is facilitated by partitioning the reacting species into primary and secondary species corresponding to a particular representation of the stoichiometric reaction matrix referred to as the canonical representation. The transport equations for the primary species combined with homogeneous and heterogeneous equilibria result in a system of coupled, nonlinear algebraic/partial differential equations which completely describe the evolution of the system in time. Spatially separated phase assemblages are accommodated in the model by altering the set of independent variables across surfaces of discontinuity. Constitutive relations for the fluid flux corresponding to primary species are obtained describing transport of both neutral and charged species by advection, dispersion and diffusion. Numerical implementation of the transport equations is considered and both explicit and implicit finite difference algorithms are discussed. Analytical expressions for the change in porosity and permeability with time are obtained for an assemblage of minerals reacting reversibly with a hydrothermal fluid under quasi-steady state conditions. Fluid flow is described by Darcy's law employing a phenomenological expression relating permeability and porosity. Finally an expression for the local retardation factor of solute species is derived for the case of advective transport in a single spatial dimension which accounts for the effects of homogeneous and heterogeneous equilibria including adsorption on the rate of advance of a reaction front. The condition for the formation of shock waves is given.
Surface reconstructions of InGaAs alloys

Abstract The atomic surface structures of InGaAs lattice-matched and 1.9% compressively strained alloys were examined using in situ scanning tunneling microscopy. The surface of the lattice-matched films is comprised of an anion-rich but mixed-termination (4 × 3) or (6 × 4) reconstruction. The strained alloys exhibit regions of the same reconstructions, in addition to pockets of α2(2 × 4) in the case of the In0.27Ga0.73As/GaAs films, and β2(2 × 4) in the case of the In0.81Ga0.19As/InP. Annealing experiments show that the coverage of the α2(2 × 4) and β2(2 × 4) regions decreases with increasing annealing time. Therefore, it is postulated that the composition of these (2 × 4) reconstructions is enriched in In compared to the (4 × 3)/(6 × 4).
Testing for Interaction in Multiple Regression

Contrary to a recent claim, the inclusion of a product term in a multiple regression is a legitimate way to test for interaction. The unstandardized coefficient and the t-test for the product term are unaffected by the addition of arbitrary constants to the variables in the model. Certain other statistics are affected by this change, however, indicating that some hypotheses relating to interaction are not meaningfully testable unless variables are measured on ratio scales.
Nanometer Distances between Swimming Bacteria and Surfaces Measured by Total Internal Reflection Aqueous Fluorescence Microscopy

Bacterial adhesion to surfaces can lead to the formation of biofilms and the development of infection. Bacteria which are motile reach surfaces faster than nonmotile bacteria and may adhere more rapidly than nonmotile bacteria. The motility of a species has also been implicated as a factor in virulence. Understanding the role that motility plays in bringing a bacterium in contact with a surface and its subsequent adherence can aid in designing strategies to prevent adhesion. In this paper, we describe the development of a total internal reflection aqueous fluorescence (TIRAF) microscope to measure the distance between an E. coli bacterium and a clean quartz surface as the bacterium was swimming laterally along the surface. This technique is distinct from other related approaches such as atomic force microscopy and total internal reflection fluorescence microscopy because it does not require the immobilization of cells on a surface for the measurement. The TIRAF microscope was capable of capturing images o...
Heating Effects on The Young's Modulus of Films Sputtered onto Micromachined Resonators

Surface-micromachined polysilicon lateral resonant structures were fabricated and used to determine the temperature dependence of the Young’s modulus of the polysilicon. This is done by passing a dc current through the beams during resonance testing, resulting in Joule-heating. The temperatures are calibrated by increasing the dc current until the melting point of silicon is attained. The calculated Young’s moduli agree well with reported values for single crystal silicon. In addition, metal films were sputter-deposited onto the polysilicon resonators, and similar experiments performed on the composite devices to determine the temperature dependence of the modulus of the sputtered films. Ni films demonstrate a linear decrease in Young’s modulus with temperature. TiNi films demonstrate two distinct modulus values with an intermediate transition region, due to the temperature-induced reversible phase transformation exhibited by TiNi.
Diversity in Engineering (DinE) Bibliography Research Brief

The Diversity in Engineering (DinE) online bibliography is now available at http://inesweb.org/dine/. The bibliography is a searchable collection of journal articles and conference papers published...
The supply and demand for imports and exports in a simultaneous model

Previous studies on the behaviour of aggregate exports and imports have tended to ignore the simultaneous relationship between quantity and price. This paper investigates the price responsiveness of export and import demand and supply in eight African countries. The results indicate that export demand price elasticities are smaller when the sample is African. The import supply and demand elasticities were found to be generally large. The Marshall–Lerner condition of balance of payment stability is found to be easily satisfied. A positively sloped function of export supply is found to exist for a majority of countries in the sample. The average time lag of export supply is found to be about a year. The disequilibrium model is found to be more appropriate for import demand, import supply and export supply.
Gigascale integration for teraops performance-challenges, opportunities, and new frontiers

VLSI system performance increased by five orders of magnitude in the last three decades, made possible by continued technology scaling, improving transistor performance to increase frequency, increasing integration capacity to realize complex architectures, and reducing energy consumed per logic operation to keep power dissipation within limit. The technology treadmill will continue, providing integration capacity of billions of transistors, enabling unprecedented teraops levels of performance; however, with some adverse effects posing barrier.
Demand estimation when some prices are unobserved: an application to fresh lettuce

This study proposes a linear two-stage approach to derive prices of observations when reported consumption is zero. In the first stage, demand equations are estimated using an ad hoc filling of unobserved prices. Then, each estimated demand equation is solved for price and a numerical estimate of the price, which drives consumption to zero, referred to as the choke price, is calculated. The demand equations are re-estimated with the choke-price series replacing the initial ad hoc prices. Although differing claims can be made on the appropriateness of the chosen method for filling prices, we demonstrate significant differences in statistical fit of the demand model and own-price demand elasticities among alternative approaches.
Trials that matter: two faces of progress in the treatment of age-related macular degeneration.

Age-related macular degeneration (AMD) is a common ocular condition that may destroy central vision and may have a devastating effect on the quality of life of older people. Two recently published ...
Numerical Modeling of Pressure Losses Caused by Bends in Pneumatic Conveying Pipeline

Pneumatic conveying pipelines are widely employed in many industries to transport granular solids. Use of bends with various turning radii in these pipelines is mandatory and it is well known that the bends cause a loss of energy which results in an additional pressure drop. The pressure loss associated with various bends in pneumatic conveying pipelines was studied numerically. The numerical modeling results were validated against laboratory measurements, and parametric studies were performed to examine various factors that affect the pressure loss caused by bends in pneumatic conveying pipelines. Since the numerical results supply flow information at every location in the pipeline, the flow pattern and pressure field of air and pellet were resolved in detail to investigate the mechanism of the pressure loss in such systems.Copyright © 2009 by ASME
A zonal organization of odorant receptor gene expression in the olfactory epithelium

The mechanisms by which mammals discriminate a vast array of diverse odors are poorly understood. To gain insight into the organizational strategies underlying this discriminatory capacity, we have examined the spatial distribution of odorant receptor RNAs in the mouse olfactory epithelium. We have observed topographically distinct patterns of receptor RNAs suggesting that the nasal cavity is divided into a series of expression zones. The zones exhibit bilateral symmetry in the two nasal cavities and are organized along the dorsal-ventral and medial-lateral axes. Within each zone, a neuron may select a gene for expression from a zonal gene set via a stochastic mechanism. The observed zonal patterning may serve as an initial organizing step in olfactory sensory information coding.
Doppler ultrasound of the prostate in normal dogs and in dogs with chronic lymphocytic-lymphoplasmocytic prostatitis.

The prostate gland of 11 normal dogs and five dogs with histologically confirmed chronic lymphocytic or lymphoplasmocytic prostatitis were imaged with grey-scale and Doppler ultrasound. Three vessel types (prostatic artery, capsular artery and parenchymal artery) were identified with color Doppler and the resistive index and maximum and minimum velocities were measured with pulsed wave Doppler. No differences between normal dogs and dogs with prostatitis was identified in either grey-scale ultrasound or in any Doppler parameters measured. Regardless of histologic diagnosis, acepromazine (0.05 mg/kg i.v.) caused a significant decrease in capsular artery maximum and minimum velocities and prostatic artery resistive index. This study establishes normal Doppler ultrasound parameters for the intact male canine prostate gland. Additional studies are necessary to further evaluate the clinical utility of Doppler ultrasound in canine prostatic diseases.
How Accurate Is Ground-Penetrating Radar for Bridge Deck Condition Assessment?

As ground-penetrating radar (GPR) is increasingly used for assessing the condition of bridge decks, quantifying and controlling the quality of GPR measures becomes an important challenge. A methodology developed to assess the accuracy of deck condition measures is presented, and its use in a case study involving real data is demonstrated. The latter are generated during GPR applications on a large bridge deck and are processed with a commercial image-processing algorithm. The measures extracted from the processed GPR data are the rebar reflection amplitude and the dielectric constant of the deck material. The accuracy of the GPR assessments is evaluated by comparing core data (ground truth) with the GPR measures. The methodology uses appropriate statistical characteristic curves for quality control. It is based on a use of data to plot the probabilities of true detection versus false detection. Image interpretation requires using a threshold value (typically established from experience) selected to optimize true and false detection rates. The results of the case study indicate that rebar reflection data detect defects of the bridge decks at a 75% true detection rate with a 15% false detection rate. The dielectric data generated during field testing appear not to adequately represent the condition of the bridge deck because of the presence of latex-modified concrete overlay. The details of this finding and important conclusions are presented and discussed.
Topology distribution cost vs. efficient routing in large networks

Routing a message in a network is efficient (in terms of weight of the path used to carry the message) when nodes know the full topology of the network. This may not be the case in large networks since a network may be composed of smaller autonomous pieces by design or by requirements on performance, with each piece having less than complete information about other pieces. We present a trade-off between the amount of topology information exchanged among these pieces and the efficiency of routing in the network. The large network that we study is a collection of networks connected by boundary nodes. Each boundary node knows the topology of its network and the connectivity of networks to each other. The question addressed here is how much topology information about each network should be distributed to other networks in order to achieve reasonably efficient routing.
Preparation and Characterization of Reduced-Charge Hectorites

A series of reduced-charge (RC) hectorites were prepared by multiple heat (250°C) treatments of Mg-saturated hectorites (SHCa-1 ). Cation exchange capacity (CEC) measurements and alkylammonium exchange indicated that a decrease in layer charge occurred with each Mg-250 treatment. Chemical analyses showed that decreases in structural Li and increases in structural Mg contents coincided with charge reduction. Fluorescence measurements of adsorbed quinoline indicated that the hectorite surface was acidified during charge reduction; hydroxyl group deprotonation is a possible source for the acidity. Fourier transform infrared spectra (FTIR) indicated that the Mg-250 treatment induced the loss of structural Li and shifted the SiO stretch band to a position similar to that in talc. The relative intensities of the OH and SiO stretch bands in FTIR spectra suggest that some of the hydroxyl groups in hectorite were lost, possibly by deprotonation. However, thermogravimetric data (TG) reveal no significant difference in the hydroxyl contents of the hectorites.
GATT-WTO Creates Trade Opportunities for Egyptian Agribusiness

Abstract With an increasing population and a small arable land base Egypt's trade balance for agricultural goods has been negative. This study analyzes the impact of GATT on that trade balance. Results suggest that GATT could help turn Egypt's agricultural trade deficit into a surplus. Since Egypt's accession to GATT the United States and several Arab countries have become bigger trade partners. GATT may have also helped Egypt's potato, rice and cotton industries become more competitive in international markets. Issues that will affect future trade patterns include tariff reductions, export destinations, import sources, product diversity, currency exchange rates and value-added developments.
The Impact of Health Status on Dispersal Behavior in Banded Mongooses (Mungos mungo)

While disease and injury have obvious impacts on mortality, they can have less understood non-lethal impacts on behavior. These behavioral effects might have a significant consequences for population-level disease dynamics if diseased individuals are more or less likely to disperse. We opportunistically observed dispersal events in banded mongooses (Mungos mungo) that were either healthy or unhealthy due to injury and/or clinical signs of a novel tuberculosis pathogen, Mycobacterium mungi. We found that diseased and/or injured mongooses were significantly less likely to disperse than healthy individuals, suggesting that disease may have an important consequences for dispersal that could in turn affect population-level disease dynamics.
Oxygen transfer in membrane-ceramic composite materials for immobilized-cell monolithic reactors.

A novel bioreactor concept is described for facilitated gas-liquid mass transfer, specifically oxygen supply, at low shear rates and low power input. The cross flow monolithic reactor is a single piece of ceramic consisting of continuous flow passages manifolded in a cross flow arrangement. Liquid medium circulates through the passages in one direction and gas circulates through the passages in an orthogonal direction; thus, the two streams are contacted across a large area of a porous ceramic, gas permeable membrane composite.A test cell was designed and used to measure the rate of oxygen transfer across such a composite. High oxygen transfer rates (6.62g O(2) x l(-1) x hr(-1)), with minimal power requirements (estimated below 5 x 10(-3) watts/l reactor volume), were found. This corresponds to a transfer efficiency of greater than 1000 kg O(2)/kW . hr, orders of magnitude greater than the values reported by Serieys, et al.(14) due to the low flow rates and low pressure drops required in a cross flow monolith. This contacting configuration could be employed with highly aerobic, immobilized-cell fermentations to enhance oxygen transfer rates with a parallel decrease of process power requirements.
Design of a variable field prototype PET camera

A prototype PET camera has been designed and is being constructed to test the concept, and develop the engineering design and production methodology for a variable field PET camera. The long term goal of the design is to develop a lower cost, high resolution PET camera. The camera has eight detector heads which form a closely packed octagon detector ring with an average diameter of 44 cm for brain/breast and animal model imaging. The heads can be translated radially to a maximum ring diameter of 70 cm for whole body imaging. In the larger diameter modes, the camera rotates 45/spl deg/ during imaging. The camera heads can be set to intermediate positions to fit the camera to the subject size to maximize detection sensitivity and sampling uniformity. Special design features for imaging the breast and the axillary metastases have been incorporated. The detector design implemented is the quadrant sharing photomultiplier (PMT) design using circular 19 mm PMT. The BGO detector pitch size is 2.7/spl times/2.7 mm. The prototype camera images 27 slices simultaneously with an axial field of view (FOV) of 39 mm. The prototype's limited axial FOV, which is appropriate for testing the camera concept, would be expanded in a next-generation clinical camera implementation. Preliminary simulation studies have been performed to evaluate the resolution, sensitivity, and sampling uniformity.
Search for New Drugs for Treatment of Tuberculosis

The purpose of this brief commentary is to describe the growing effort to discover new drugs that can be used to treat disease caused by Mycobacterium tuberculosis . In this regard, it is estimated that over 8 million people contract tuberculosis each year, and approximately 2 to 3 million people
A Glimpse into the Future of Diagnostics

In this issue of Clinical Chemistry , a report by the teams of Sam Sia (at Columbia) and Vincent Linder (at Claros/OPKO), together with a large group of collaborators, provides a remarkable example of what happens when one rethinks, both creatively and practically, how to collect diagnostic information in the developing world (1). By combining innovative engineering, a mixture of new and familiar technologies, good design, and careful attention to limited resources (human, financial, energetic), they have produced an integrated system whose impressive capabilities suggest a new approach to the design of portable diagnostic systems: keep the quality up (in fact, provide improved performance) relative to existing diagnostic technology; decrease costs; reduce the need for trained personnel; and use the web to move, store, and apply information. These goals constitute an aspirational roadmap for diagnostic systems for the developing world; this portable diagnostic system suggests that this roadmap can be followed practically. But the significance of the work goes beyond the developing world. It represents one brick in what will surely be the foundation of a revolution that will fundamentally change the technical and business structure of diagnostics. The business model for diagnostics (as for many aspects of the medical systems of the developed world) is almost incredibly archaic in its treatment of information. It assumes that the primary value of diagnostic information is in defining the nature of disease, and the course of treatment, for individual, symptomatic patients. It also assumes that diagnostic information will usually be expensive and come from complex diagnostic technology managed and priced to maximize profitability. In this model, because information is expensive, it will be available only in cases of obvious need (i.e., for symptomatic disease). The most primitive issues of extracting value from masses of population-wide data, or even of handling the information …
Total Bladder and Posterior Urethral Reconstruction: Salvage Technique for Defunctionalized Bladder with Recalcitrant Posterior Urethral Stenosis

Purpose: Recalcitrant posterior urethral stenosis is a challenging disease. When combined with a defunctionalized bladder, cutaneous urinary diversion is the most common surgical option. We present a novel technique of total lower urinary tract reconstruction, combining salvage cystectomy, ileal neobladder formation and urethral pull-through, as an orthotopic alternative in patients with a defunctionalized bladder and recalcitrant posterior urethral stenosis.Materials and Methods: We completed a retrospective review of 8 patients who underwent salvage cystectomy, orthotopic ileal neobladder formation and urethral pull-through. Artificial urinary sphincter placement was performed in a staged fashion. Six patients received prostate cancer treatment including radiation therapy, 1 had urethral disruption after robotic radical prostatectomy, and 1 experienced bladder rupture and urethral distraction injury during a motorcycle accident. Patient demographics, operative variables and postoperative outcomes were e...
The precautionary principle and traditional risk assessment : Rethinking how we assess and mitigate environmental threats

The article begins by problematizing the risk assessment and precautionary principle frameworks. From here, attention turns toward the development of an alternative, more holistic, scheme for assessing and mitigating environmental threats. Recognizing that the assessment and mitigation of environmental threats is a multilayered process, discussion centers on the question of who is involved in the production process—from research to development to threat assessment. Including a variety of stakeholders in both the “front” and “back” ends of production thus also places focus on the material side of this process, particularly in terms of what is being produced and released into the environment. Traditional risk assessment and the precautionary principle are therefore presented as shortsighted strategies for threat assessment. Instead, a more open approach is discussed, which involves greater public involvement through the entire life cycle of a product, from “cradle to cradle”.