cssi/SciSciGPT-SciSciNet huggingface dataset:
“Building glass refrigerators in the desert”: discourses of urban sustainability and nation building in Qatar

Planners around the Arab Gulf states are increasingly drawing on narratives about “urban sustainability,” despite the fact that the explosive growth of urban centers in the Arabian desert largely defies the logic of sustainability. In this article, I consider how and with what effect these narratives have been deployed by various actors in Doha, Qatar. Eschewing a simple economistic reading, I highlight political geographic context and analyze how actors mobilize and rework these discourses. Drawing on mixed-methods fieldwork in Fall 2013, I illustrate how sustainability narratives are mobilized together with nationalist tropes about modernizing Qatar and building up the country’s international prestige, while preserving local traditions and culture through the built environment. With a focus on recent efforts to green Doha, this analysis sheds light on the disciplining function of nationalist discourses in the production and constitution of what it means to label development practices “green” in contempo...
Plasma Volume Expansion Resulting from Interference with Adrenergic Function in Normal Man

Guanethidine was administered to 10 normal subjects in order to examine the effects of reduced adrenergic function on plasma volume. An increase in the plasma volume was observed averaging 21.4% after 1 week, and 12.1% and 13.1% after 2 and 3 weeks of drug administration. A similar change in plasma volume resulted when alphaadrenergic blockade was produced with phenoxybenzamine. These changes occurred in the absence of sodium retention and were associated with attenuation of forearm venous sympathetic reflexes and a rise in forearm venous compliance. The increase in venous compliance which was observed was proportional to the changes in plasma volume in these subjects. Thus, the sympathetic nervous system through its control of venous resistance may provide a means whereby the blood volume can be regulated.
A note on the mathematics of "catch-up" growth.

Extract: The concept of “catch-up” growth is presented in terms of growth velocity. Mathematically speaking, size function is the integral of velocity function, regardless of the form of the function. The process of “catch-up” growth will be complete only when the integrated velocity excess during recovery matches the previous velocity deficit. Speculation: An appreciation of the importance of growth velocity, i.e., change in body size with respect to time (dS/dt), may help in understanding the magnitude of the processes involved in recovery from undernutrition, and perhaps overnutrition as well.
A new sensing skin for qualitative damage detection in concrete elements: Rapid difference imaging with electrical resistance tomography

Abstract In this paper we investigate whether a thin layer of electrically conductive materials that is painted to the surface of concrete elements can be used as sensing skin to detect and locate cracking and damage in the concrete substrate. Cracking of the concrete results in the rupture of the sensing skin, thus locally increasing its electrical resistivity. We monitor the local change in the electrical resistivity of the sensing skin using electrical resistance tomography. In this work, we utilize difference imaging scheme. Experiments on polymeric substrates as well as on concrete substrates are performed. The results indicate that the developed sensing skin can be successfully used to detect and locate cracking and damage on concrete and potentially other nonconductive substrates.
A Model for Flow and Deformation in Unsaturated Swelling Porous Media

A thermomechanical theory for multiphase transport in unsaturated swelling porous media is developed on the basis of Hybrid Mixture Theory (saturated systems can also be modeled as a special case of this general theory). The aim is to comprehensively and non-empirically describe the effect of viscoelastic deformation on fluid transport (and vice versa) for swelling porous materials. Three phases are considered in the system: the swelling solid matrix s, liquid l, and air a. The Coleman–Noll procedure is used to obtain the restrictions on the form of the constitutive equations. The form of Darcy’s law for the fluid phase, which takes into account both Fickian and non-Fickian transport, is slightly different from the forms obtained by other researchers though all the terms have been included. When the fluid phases interact with the swelling solid porous matrix, deformation occurs. Viscoelastic large deformation of the solid matrix is investigated. A simple form of differential-integral equation is obtained for the fluid transport under isothermal conditions, which can be coupled with the deformation of the solid matrix to solve for transport in an unsaturated system. The modeling theory thus developed, which involves two-way coupling of the viscoelastic solid deformation and fluid transport, can be applied to study the processing of biopolymers, for example, soaking of foodstuffs and stress-crack predictions. Moreover, extension and modification of this modeling theory can be applied to study a vast variety of problems, such as drying of gels, consolidation of clays, drug delivery, and absorption of liquids in diapers.
Hypoxia-ischemia stimulates hippocampal glutamate efflux in perinatal rat brain: an in vivo microdialysis study.

ABSTRACT: We used in vivo microdialysis to determine the impact of a focal hypoxic-ischemic insult on hippocampal amino acid efflux in the immature brain. Microdialysis probes were inserted into the right hippocampus of postnatal d 7 rats. To induce hypoxic-ischemic injury, the right carotid artery was ligated and animals were exposed to 8% oxygen for 2 h (p = 6, histologically verified). Ten 20-min dialysis fractions were collected from each animal: three sequential 20-min baseline samples, six samples during hypoxia, and a recovery sample in room air. Eight amino acids were detected in dialysates with a HPLC assay. There was marked intra- and interanimal variation in glutamate efflux; mean glutamate efflux increased from 17 pmol/min in baseline samples to 51 in the 2nd h of hypoxia (p = 0.002, Kruskal Wallis test). There was a concurrent decline in glutamine efflux (310 to 207 pmol/min, p = 0.0005). Alanine efflux doubled during hypoxia (p = 0.015). There were no changes in efflux of the other five amino acids analyzed. In this experimental model of perinatal stroke, during the acute evolution of hypoxic-ischemic brain injury, transient large increases in glutamate efflux and corresponding declines in glutamine efflux were detected. These data support the hypothesis that synaptic concentrations of the endogenous excitatory amino acid glutamate increase during the evolution of hippocampal ischemic injury.
Efficient Global Aerodynamic Modeling from Flight Data

A method for identifying global aerodynamic models from flight data in an efficient manner is explained and demonstrated. A novel experiment design technique was used to obtain dynamic flight data over a range of flight conditions with a single flight maneuver. Multivariate polynomials and polynomial splines were used with orthogonalization techniques and statistical modeling metrics to synthesize global nonlinear aerodynamic models directly and completely from flight data alone. Simulation data and flight data from a subscale twin-engine jet transport aircraft were used to demonstrate the techniques. Results showed that global multivariate nonlinear aerodynamic dependencies could be accurately identified using flight data from a single maneuver. Flight-derived global aerodynamic model structures, model parameter estimates, and associated uncertainties were provided for all six nondimensional force and moment coefficients for the test aircraft. These models were combined with a propulsion model identified from engine ground test data to produce a high-fidelity nonlinear flight simulation very efficiently. Prediction testing using a multi-axis maneuver showed that the identified global model accurately predicted aircraft responses.
Induced wetting of polytetrafluoroethylene by atomic layer deposition for application of aqueous-based nanoparticle inks

Abstract Atomic layer deposition of aluminum oxide is shown to control the surface energy and wetting properties of polytetrafluoroethylene (PTFE) films and membranes. Independent of deposition temperature, gradual and abrupt wetting transitions were observed for PTFE films and membranes, respectively. To assess the enhanced compatibility of treated PTFE substrates with nanoparticle inks, drop casting and inkjet printing of silver nanoparticle solutions are performed and analyzed by optical microscopy and time of flight secondary ion mass spectroscopy. Untreated PTFE substrates showed poor compatibility with the nanoparticle inks, drying in a coffee ring pattern, whereas aluminum oxide treated PTFE substrates exhibited uniform silver nanoparticle distribution after drying.
A Maximum Likelihood Approach to Test Validation with Missing and Censored Dependent Variables.

A maximum likelihood approach is described for estimating the validity of a test (x) as a predictor of a criterion variable (y) when there are both missing and censoredy scores present in the data set. The missing data are due to selection on a latent variable (y s ) which may be conditionally related toy givenx. Thus, the missing data may not be missing random. The censoring process in due to the presence of a floor or ceiling effect. The maximum likelihood estimates are constructed using the EM algorithm. The entire analysis is demonstrated in terms of hypothetical data sets.
Age-related changes in the pharmacological improvement of retention in senescence accelerated mouse (SAM)

The P/8 line of the senescence accelerated mouse (SAM) model exhibits characteristics of aging early in its lifespan including an early onset of impaired learning and memory which becomes progressively worse with age. Age-matched controls of the R/1 line do not show impaired learning and memory. We report age-related changes in the drug dosage needed to improve 1 week retention in the P/8 but not R/1 line. The results indicate that 8-month-old P/8 mice show a reduced sensitivity to memory enhancing doses of cholinomimetics and an increased sensitivity to a serotonin antagonist compared to 4-month-old mice. By 12 months of age, improvement of retention required still higher doses of cholinomimetics and even lower doses of the serotonin antagonist. Higher doses of an opioid antagonist and a dopamine agonist were needed to improve retention in 12-month-old mice. A GABA antagonist and an alpha noradrenergic agonist improved retention at the same dose in mice 4, 8, and 12 months of age.
Optimal frequency ranges for extracting information on autonomic activity from the heart rate spectrogram.

Abstract Heart rate variability spectrum analysis provides useful quantitative indices of neural control of the SA node. This method is attractive both for its simplicity and the lack of invasive instrumentation, particularly for human investigation. The differing spectral characteristics of parasympathetic and sympathetic control of heart rate allows separate measurement. However, there are widely varying opinions as to the appropriate frequency bands to represent these two inputs. We compared the heart rate variability spectra of 16 humans in supine and upright positions. Adequate measures of parasympathetic or sympathetic activity change should correlate respectively inversely or directly with heart rate change. Frequently used spectral measures of sympathetic activation did not correlate with heart rate changes. With optimization of frequency bands, we found that restricting the sympathetic band to frequencies below 0.1 Hz and above 0.05 Hz (0.055 to either 0.086–0.098 Hz), and dividing by total spectral amplitude 0.004–0.5 Hz (to account for parasympathetic fluctuations within the sympathetic band) produced the best results. The parasympathetic band was best from 0.1 Hz to a frequency greater than that of the respiratory sinus arrhythmia. The optimization method detailed here is easily applied to circumstances other than active orthostasis, and should provide a means of empirically determining useful frequency limits.
The putative movement domain encoded by nepovirus RNA-2 is conserved in all sequenced nepoviruses

Significant similarity among putative movement domains in polyproteins encoded by RNA-2 of six nepoviruses is described.
Division blocks and the open-ended evolution of development, form, and behavior

We present a new framework for artificial life involving physically simulated, three-dimensional blocks called Division Blocks. Division Blocks can grow and shrink, divide and form joints, exert forces on joints, and exchange resources. They are controlled by recurrent neural networks that evolve, along with the blocks, by natural selection. Division Blocks are simulated in an environment in which energy is approximately conserved, and in which all energy derives ultimately from a simulated sun via photosynthesis. In this paper we describe our implementation of Division Blocks and some of the ways that it can support experiments on the open-ended evolution of development, form, and behavior. We also present preliminary data from simulations, demonstrating the reliable emergence of cooperative resource transactions.
A backdoor to the nucleus that runs in the family

Yoshimura and colleagues show that HEAT proteins that are involved in diverse cellular functions may facilitate their own translocation through the nuclear pore complex, owing to their structural similarity to nuclear transport receptors of the karyopherin β family.
Synthetic peptides of the hamster beta 2-adrenoceptor as substrates and inhibitors of the beta-adrenoceptor kinase.

1. The beta-adrenoceptor is one of a number of G protein-coupled receptors which have been proposed to contain seven transmembrane alpha- helices. The function of this receptor appears to be regulated by phosphorylation by a specific enzyme, the beta-adrenoceptor kinase. Synthetic peptides which comprise each of the proposed intra- and extracellular domains of the beta 2-adrenoceptor have been tested as potential substrates and inhibitors of the beta-adrenoceptor kinase. 2. Two peptides which encompass the middle and terminal portions of the carboxyl tail of the receptor served as substrates by beta-adrenoceptor kinase. The kinetics of the phosphorylation reaction, however, suggest that these peptides are 10(6)-fold poorer substrate than the agonist occupied receptor. 3. A number of synthetic peptides also served as inhibitors of beta 2-adrenoceptor phosphorylation by beta-adrenoceptor kinase. In particular, a peptide which comprised the first intracellular loop of the beta 2-adrenoceptor (amino acids 56-74) inhibited most effectively with an IC50 of 40 microM. 4. These results suggest that multiple intracellular regions of the beta-receptor may serve as potential sites of interaction with beta-adrenoceptor kinase. Moreover, these regions may serve as potential targets for the development of specific inhibitors of beta-adrenoceptor kinase which could be used to block homologous desensitization.
Defect inspection of disposable glucose test strips using machine vision

This paper presents a machine vision system for defect inspection disposable glucose test strips. The proposed system first lightened and captured image of flawless glucose test strip while offline training. The captured image was processed through image processing technology to establish standard projection data of silver paste and carbon rubber in flawless glucose test strips. Then the measured blood glucose test strips were processed with the same lighting and image processing procedures when online detection. The defects of the measured blood glucose test strips were inspected by the projection data comparison. Experiments show that the proposed system can effectively detect three main defects on glucose test strips, i.e., silver exposing, short circuit of carbon paste electrode and unglued carbon plastic electrode.
Methylphenidate use in children and risk of cancer at 18 sites: results of surveillance analyses

Purpose A recent report linked methylphenidate (MPH) use in children to cytologic abnormalities in plasma lymphocytes, a possible cancer biomarker. The purpose of this study was to investigate the association of MPH use and childhood cancer risk. Methods Using automated pharmacy databases and the SEER-affiliated cancer registry of the Kaiser Permanente Medical Care Program (KPMCP), we compared cancer rates at 18 sites among 35 400 MPH users who received it before age 20 to rates among KPMCP membership (age, sex, and calendar year standardized). Medical records of MPH exposed cancer cases were reviewed to identify the presence of established risk factors. Results There were 23 cancers among MPH users, versus 20.4 expected (standardized morbidity ratio, SMR = 1.13, 95% confidence interval (0.72, 1.70)). Given the small number of cancers, site-specific SMR estimates were imprecise. Only one SMR was statistically significant at the p < 0.05 level, which given the number of comparisons is consistent with the absence of a true association at any site. MPH use was associated with increased risk of lymphocytic leukemia (SMR = 2.64 (1.14, 5.20)), based on eight observed cases). The medical records of these exposed cases did not reveal any lymphocytic leukemia risk factors (prior cancer, radiotherapy or chemotherapy, or Down syndrome). Conclusions Our results are consistent with no moderate or strong association between MPH use and cancer risk in children, although our ability to examine dose and duration of use or risk at specific sites was limited by small numbers. Further study of MPH use and lymphocytic leukemia risk is needed to determine whether our results are due to chance alone. Copyright © 2007 John Wiley & Sons, Ltd.
Dimensions of Family Conflict and Their Influence on Child and Adolescent Adjustment

Using the first (1987-1988) and second (1992-1994) waves of the National Survey of Families and Households, this study examines the concurrent and longitudinal influences of interparental conflict and parent-child conflict on child and adolescent adjustment. Analyses focus on 542 intact families, each with a randomly selected focal child aged 5 to 11 at time 1 and aged 10 to 17 at time 2, Results indicate that both parent-child and parent-adolescent conflict are critical predictors of children's and adolescents' socioemotional adjustment. Interparental conflict, by contrast, is less important for adjustment in middle and late childhood as well as in adolescence. The findings extend previous research by suggesting that the salience and threat of interparental conflict subside as children make the transition into adolescence.
Lesson Plan Analysis as a Program Evaluation Tool.

The use of teacher lesson plans as a tool to measure program effectiveness was explored as a part of an overall evaluation of a gifted program in grades 1 to 6. A Lesson Plan Evaluation Form (LPEF)...
Family history and colorectal cancer: predictors of risk.

Introduction: While the association between family history of colorectal cancer in first-degree relatives and risk of developing colon cancer has been well defined, the association with rectal cancer is much less clear. The purpose of this study is to define rectal cancer risk associated with family history of colorectal cancer in first-degree relatives. We also evaluate diet and lifestyle factors associated with developing colorectal cancer among participants with a positive family history. Methods: Data were available from two population-based case–control studies of colon and rectal cancer. Participants were members of the Kaiser Permanente Medical Care Program (KPMCP) or residents of the state of Utah. Cases were first primary colon cancer diagnosed between 1991 and 1994 (n = 1308 cases and 1544 controls) or rectal cancer diagnosed between 1997 and 2001 (n = 952 cases and 1205 controls). Results: A family history of colorectal cancer in any first-degree relatives slightly increased risk of rectal cancer (OR: 1.37 95% CI: 1.02–1.85). Family history of colorectal cancer was associated with the greatest risk among those diagnosed at age 50 or younger (OR: 2.09 95% CI: 0.94–4.65 for rectal tumors; OR: 3.00 95% CI: 0.98–9.20 for distal colon tumors; and OR: 7.88 95% CI: 2.62–23.7 for proximal colon tumors). Factors significantly associated with cancer risk among those with a family history of colorectal cancer, included not having a sigmoidoscopy (OR: 2.81 95% CI: 1.86–4.24); a diet not Prudent, i.e. high in fruits, vegetables, whole grains, fish and poultry, (OR: 2.79 95% CI: 1.40–5.56); smoking cigarettes (OR: 1.68 95% CI: 1.12–2.53), and eating a Western diet, i.e. a diet high in meat, refined grains, high-fat foods, and fast foods, (OR: 2.15 95% CI: 1.06–4.35). Physical inactivity was not associated with increased cancer risk among those with a positive family history of colorectal cancer. Summary: These results confirm observations reported by others that a family history of colorectal cancer increases risk of cancer among those diagnosed at a younger age. Associations with family history are weakest for rectal cancer and strongest for proximal colonic tumors. Since several diet and lifestyle factors influence development of cancer among those with a family history of the disease, there appears to be practical approaches for individuals with a family history of colorectal cancer to reduce their cancer risk.
Outcome of Henoch-Schönlein purpura nephritis treated with long-term immunosuppression.

This retrospective study investigated the outcome of 27 children (19 male) with Henoch-Schonlein purpura nephritis (HSN) of International Study of Kidney Disease in Children (ISKDC) grade 3b or higher treated with long-term immunosuppressive therapy in a single centre over a 10-year period. The mean age at presentation was 9.7 years. The median estimated glomerular filtration rate (eGFR) was 91.3 ml/min per 1.73 m2, with the median urine protein creatinine ratio (UP:UC) 556 mg/mmol. The treatment protocol comprised daily steroids and cyclophosphamide for 8–12 weeks followed by azathioprine and a reducing regimen of alternate-day steroids for 8–12 months. After a mean follow-up period of 7 years following presentation, 37% made a complete recovery, 40.7% had persistent proteinuria, 7.4% had persistent proteinuria and were on antihypertensive therapy and 14.8% had progressed to end-stage kidney failure (ESKF). Children with poor outcome were older at presentation (p 0.005), had more crescents (p 0.015) and had heavier proteinuria 6 months post initial biopsy (p 0.023). All of the four children with ESKF had nephrotic range proteinuria and greater than 50% crescents on initial biopsy. Despite long-term immunosuppression, the majority of children with HSN grade 3b or higher will have persistent renal abnormalities on long-term follow-up.
Sensitive, quantitative carbon-13 NMR spectra by mechanical sample translation

Abstract Collecting a truly quantitative carbon-13 spectrum is a time-consuming chore. Very long relaxation delays, required between transients to allow the z-magnetization, Mz, of the spin with the longest T1 to return to the equilibrium value, M0, must precede each transient. These long delays also reduce sensitivity, as fewer transients per unit time can be acquired. In addition, sometimes T1 is not known to within even a factor of two: a conservative guess for the relaxation delay then leads to very low sensitivity. We demonstrate a fresh method to bypass these problems and collect quantitative carbon-13 spectra by swapping the sample volume after each acquisition with a different portion where the magnetization is already equilibrated to M0. Loading larger sample volumes of 10–20 mL into an unusually long (1520 mm) 5 mm OD. NMR tube and vertically sliding the tube between acquisitions accomplishes the swap. The relaxation delay can then be skipped altogether. The spectra are thus both quantitative, and far more sensitive. We demonstrate the moving tube technique on two small molecules (thymol and butylhydroxytoluene) and show good carbon-13 quantification. The gain in sensitivity can be as much as 10-fold for slowly-relaxing 13C resonances. These experiments show that quantitative, sensitive carbon-13 spectra are possible whenever sufficient sample volumes are available. The method is applicable to any slow-relaxing nuclear spin species, such as 29Si, 15N and other low-γ nuclei.
Statins in perioperative prevention of acute kidney injury in patients undergoing cardiac surgery

I would like to congratulate Liakopoulos et al. 1 on their excellent work on the impact of preoperative statin use and adverse outcomes. There is a paucity of data …
Three-gap klystron output cavity at X-band

A high-power X-band klystron employing a double-gap output cavity has been operating at SLAC. Multi-gap output circuits have lower surface gradients at the interaction gaps than single-gap ones but are prone to self-oscillate due to negative beam loading and trapped higher-order modes. In the double-gap circuit design, considerable attention had been directed to deal with these stability problems. The performance of the present tube appears to be limited by gap breakdown and beam interception particularly at long pulses. A three-gap output cavity is currently under development to further reduce the gap surface gradient. Another new feature of the circuit is an enlarged downstream drift tube to improve on beam clearance. This paper discusses the considerations involved in designing a multi-gap output cavity and presents the cold test measurements on the three-gap circuit. The experimental data is compared with numerical results from the 3-D simulation code ARGUS.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Prevention of retrograde calculus migration with the Stone Cone

Retrograde calculus migration during ureteroscopic lithotripsy remains a problem in 5-40% of cases. We assessed the safety and efficacy of the Stone Cone device, in comparison with the standard flat wire basket. A total of 56 consecutive patients with ureteral calculi, suitable for ureteroscopic extraction and/or lithotripsy, where included in this prospective study. Patients were randomly allocated into two groups. In group A (30 patients), we used the Stone Cone, while in group B (26 patients) we used the standard flat wire basket. The Stone Cone was placed through a cystoscope under fluoroscopic guidance, or when necessary under direct ureteroscopic control. Whenever necessary, intracorporeal electrohydraulic lithotripsy took place in both groups. Statistical significance was assessed by the paired t-test. The mean operative time was 48.5 min in group A, and 42.4 min in group B. Intact calculus extraction was possible in 16.6% in group A, and in 7.6% in group B (P 3 mm were recorded in 30.7% in group B only (P < 0.001). None of the patients in group A required auxiliary procedures, in contrary to 23% in group B (P < 0.001). No major complications were recorded in group A, while in group B a case of major ureteral mucosal abrasion was recorded. The Stone Cone is safe and efficient in preventing retrograde stone migration and in minimizing residual fragments during ureteroscopic lithotripsy in comparison with the flat wire basket.
In situ studies of carbonyl coupling : comparisons of liquid-solid and gas-solid reactions with reduced titanium reagents

The kinetics and mechanism of the liquid-solid, titanium-induced acetone coupling reaction were investigated in order to compare liquid-solid and gas-solid carbonyl coupling. The reaction utilizing both TiCl{sub 4}- and TiO{sub 2}-derived reagents reduced with LiAlH{sub 4} was monitored using in situ total internal reflectance infrared spectroscopy to probe reactive intermediates and observe the reaction progress. These studies demonstrated that carbon-carbon bond formation via carbonyl coupling occurs below 300 K in both the liquid-solid and gas-solid versions of this reaction. In situ Fourier transform infrared spectroscopy and ex situ gas chromatography/mass spectrometry verified the previously proposed reaction sequence in which pinacols are initially formed, followed by deoxygenation to form the olefin. In addition, these spectroscopic studies confirmed the commonality of the nature of the active titanium reagent, independent of the titanium source. The broad mechanistic and energetic similarities between the liquid-solid and gas-solid versions of this reaction, combined with the low temperatures at which carbon-carbon bond formation can occur, suggest that the principal barrier to operation of carbonyl coupling as a catalytic cycle lies in concurrent catalyst reduction.
Propositional dynamic logic of regular programs

Abstract We introduce a fundamental propositional logical system based on modal logic for describing correctness, termination and equivalence of programs. We define a formal syntax and semantics for the propositional dynamic logic of regular programs and give several consequences of the definition. Principal conclusions are that deciding satisfiability of length n formulas requires time d n /log n for some d > 1, and that satisfiability can be decided in nondeterministic time c n for some c . We provide applications of the decision procedure to regular expressions, Ianov schemes, and classical systems of modal logic.
Theory of defects in vitreous silicon dioxide

Models for defects in Si${\mathrm{O}}_{2}$ fall into the two basic categories of "vacancy-bridge" and valence-alternation models. We have calculated the local electronic structure of the main defects in each model, using the tight-binding and recursion methods. The localization of each level is found and compared to that measured by ESR for the paramagnetic centers. The silicon dangling bond, the neutral oxygen vacancy, and the positively charged oxygen vacancy (${E}^{\ensuremath{'}}$ center) all give deep states near mid-gap. The Si---Si bond gives a bonding state in the lower gap and an antibonding state near the conduction-band minimum. The positive, threefold-coordinated oxygen site $\mathrm{O}_{3}^{}{}_{}{}^{+}$(${\mathrm{Si}}_{3}$) gives a state bound only by its Coulombic field. In general, all positively charged centers possess a "shallow" bound state 1-2 eV below the conduction-band minimum. Such shallow states account for the prevalence of optical absorption around 7.6 eV in Si${\mathrm{O}}_{2}$. The nonbridging oxygen introduces states just above the valence-band maximum. The peroxyl bridge and radical give states both at mid-gap and in the lower part of the gap. A broad absorption band around 5-6 eV is associated with the peroxyl radical, for the first time. It is suggested that valence-alternation defects must still be present in $v\ensuremath{-}\mathrm{S}\mathrm{i}{\mathrm{O}}_{2}$, but at a much lower concentration, of order ${10}^{15}$ ${\mathrm{cm}}^{\ensuremath{-}3}$, than previously supposed, due to a higher valence-alternation creation energy in Si${\mathrm{O}}_{2}$ than in $a\ensuremath{-}\mathrm{S}\mathrm{e}$ or $a\ensuremath{-}{\mathrm{As}}_{2}{\mathrm{Se}}_{3}$.
CILIA REGENERATION IN TETRAHYMENA AND ITS INHIBITION BY COLCHICINE

The cilia of Tetrahymena were amputated by the use of a procedure in which the cells remained viable and regenerated cilia. Deciliated cells were nonmotile, and cilia regeneration was assessed by scoring the percentage of motile cells at intervals following deciliation. After a 30-min lag, the deciliated cells rapidly recovered motility until more than 90% of the cells were motile at 70 min after amputation. Cycloheximide inhibited both protein synthesis and cilia regeneration. This indicated that cilia formation in Tetrahymena was dependent on protein synthesis after amputation. Conversely, colchicine was found to inhibit cilia regeneration without affecting either RNA or protein synthesis. This observation suggested the action of colchicine to be an interference with the assembly of ciliary subunit proteins. The finding that colchicine binds to microtubule protein subunits isolated from cilia and flagella (13) supports this possibility. The potential of the colchicine-blocked cilia-regenerating system in Tetrahymena for studying the assembly of microtubule protein subunits during cilia formation and for isolating ciliary precursor proteins is discussed.
Non-uniform Transient Gratings Induced by Laser Pulses in Nonlinear Media

The excitation of transient gratings induced by the interference of two equal parts of a short laser pulse in nonlinear media with one- or two-photon absorption is considered. The pulse-induced grating displays completely the pulse self-interference pattern; it is not periodic but has the form of a spatially non-uniform permittivity stratification. The grating amplitudes are described by pulse correlation functions. They contain information on the pulse shape and are sensitive to its phase modulation. The diffraction efficiency of the induced grating is calculated using electrodynamic perturbation theory. It is shown that the measurement of the spectral or angular distribution of the diffracted probe light enables the grating amplitude to be computed. The correlation functions of individual pulses can be determined in this way. Some applications of the pulse-induced gratings are proposed, as is a simplified technique for measuring the pulse width. The practicability of the grating in real nonlinear media ...
Combining Regional-and Local-Scale Air Quality Models with Exposure Models for Use in Environmental Health Studies

Population-based human exposure models predict the distribution of personal exposures to pollutants of outdoor origin using a variety of inputs, including air pollution concentrations; human activity patterns, such as the amount of time spent outdoors versus indoors, commuting, walking, and indoors at home; microenvironmental infiltration rates; and pollutant removal rates in indoor environments. Typically, exposure models rely upon ambient air concentration inputs from a sparse network of monitoring stations. Here we present a unique methodology for combining multiple types of air quality models (the Community Multi-Scale Air Quality [CMAQ] chemical transport model added to the AERMOD dispersion model) and linking the resulting hourly concentrations to population exposure models (the Hazardous Air Pollutant Exposure Model [HAPEM] or the Stochastic Human Exposure and Dose Simulation [SHEDS] model) to enhance estimates of air pollution exposures that vary temporally (annual and seasonal) and spatially (at census-block-group resolution) in an urban area. The results indicate that there is a strong spatial gradient in the predicted mean exposure concentrations near roadways and industrial facilities that can vary by almost a factor of 2 across the urban area studied. At the high end of the exposure distribution (95th percentile), exposures are higher in the central district than in the suburbs. This is mostly due to the importance of personal mobility factors whereby individuals living in the central area often move between microenvironments with high concentrations, as opposed to individuals residing at the outskirts of the city. Also, our results indicate 20-30% differences due to commuting patterns and almost a factor of 2 difference because of near-roadway effects. These differences are smaller for the median exposures, indicating the highly variable nature of the reflected ambient concentrations. In conjunction with local data on emission sources, microenvironmental factors, and behavioral and socioeconomic characteristics, the combined source-to-exposure modeling methodology presented in this paper can improve the assessment of exposures in future community air pollution health studies.
Apparatus for Measuring the Rate of Absorption of a Bubble in Glass

Apparatus for measuring the rate of shrinking of a bubble of gas in a small cylinder of molten glass is described with the results of experiments with oxygen in No. 9010 glass at temperatures from 1000° to 1300°C. Approximate solutions of the Stefan problem, resulting from the application of Fick's law to these experiments, are given. They predict that in the initial stages, the rate of decrease in diameter of a bubble should be proportional to the square root of the time elapsed from the beginning of the experiment and be independent of the initial diameter of the bubble. The experiments show an acceleration of the initial rate not predicted by the approximate solutions. Increasing the temperature increases the rate of shrinking of the bubbles. In all experiments, when the bubble was followed for a sufficient length of time, an end point was reached at which the shrinking virtually stopped and a residual bubble remained indicating the presence of 1 or 2%, of impurity in the oxygen.
Elasticity-based beam vibrations for various support conditions

Abstract The accuracy of common beam theories in determining resonant frequencies and mode shapes for various support conditions is investigated in this paper. This study analyzed the influence of three assumptions employed in the Euler–Bernoulli, Rayleigh, and Timoshenko beam theories by comparing their results to a three-dimensional, elasticity-based approximation for three different support cases: fixed-free, fixed–fixed, and simply-supported. Each of the theories of interest were applied to both isotropic and orthotropic beams of varying length and compared with elasticity-based solutions to study the influence of slenderness ratio and anisotropic properties. The discrepancies caused by each of these effects are discussed and suggestions for the applicability of the common beam theories are provided.
Exploratory data analysis of hyperlipidemia on the Macintosh: software tools for analysis of biochemical, clinical, and genetic variables in 1677 consecutive lipid clinic patients

Exploratory data analysis (EDA) software facilitates unstructured, iterative open exploration of complex datasets with the aid of multiple linked graphical displays. We are investigating relationships between plasma lipoproteins and coronary artery disease by retrospective analysis of 1677 consecutive UCSF Lipid Clinic patients. Our preliminary experience is with Data Deck 3.0 although several additional software programs (JMP 2.0, Systat 5.1, Minitab 8.0, StatView 4.0) are mentioned. Lipid diagnosis (751 women and 925 men) was 22% primary hypercholesterolemia, 19% combined hyperlipidemia, 3% dysbetalipoproteinemia, 15% endogenous lipemia, 4% mixed lipemia, 5% elevated Lp(a) and 32% with no major lipid abnormality. We found the Macintosh platform (68030) to be flexible and powerful for analysis of moderate size (less than 1 Mb) clinical datasets. High resolution color monitors (1024 MX 768 pixels), fast hard disks (<18 msec) and moderate amounts of system memory (8 + Mb) facilitate exploratory analysis.
Finding dignity in dirty work: the constraints and rewards of low-wage home care labour

The ageing of the population in the US and elsewhere raises important questions about who will provide long-term care for elderly and disabled people. Current projections indicate that home care workers--most of whom are unskilled, untrained and underpaid--will increasingly absorb responsibility for care. While research to date confirms the demanding aspects of the work and the need for improved working conditions, little is known about how home care workers themselves experience and negotiate their labour on a daily basis. This paper attempts to address this gap by examining how home care workers assign meaning to their 'dirty work'. Qualitative interviews suggest that home care workers have a conflicted, often contradictory, relationship to their labour. Workers identify constraints that compromise their ability to do a good job or to experience their work as meaningful, but they also report several rewards that come from caring for dependent adults. I suggest workers draw dignity from these rewards, especially workers who enter home care after fleeing an alienating service job, within or outside the healthcare industry.
Block exemptions and the new automotive supply chains

Following concern by consumer groups over "cosy cartels" and price-fixing in the UK, new rules were implemented to remove car manufacturers from block exemptions to EU Competition Law (BER). Cutting the cord between manufacturers and dealerships who can retail and service vehicles, they expose the automotive market place to the full force of the consumer and allow new and potentially more competitive distribution channels to emerge. BER introduces seven fundamental changes to the distribution of new vehicles, aftersales service and parts. These changes include: (1) dealers and repair centers can set up networks across the UK, (2) dealers can sell more than one brand, (3) dealers and repair centers can expand networks across Europe, (4) intermediaries can enter, (5) sales and service are separated, (6) independent repairers can set up multi-franchised and European repair chains, and lastly (7) repairers have the freedom in where they source parts. With this move, BER is opening up the market for multi-branded franchises and separate sales and service. It also provides scope for networks to develop across Europe, which are free to take advantage of synergies in markets and logistics arrangements.
Water Yield Increases Through Surface Dusting of a Permanent Icefield

: Water yields from a permanent icefield were increased by 28 percent through surface dusting with carbon black. On July 4, 1972, approximately 15 acres (60,700 m2) of a permanent icefield were treated with 150 lbs. per acre (16.8 g/m2) of commercial carbon black. The icefield was located on the eastern slope of the Colorado Front Range at an elevation of 11,500 feet (3500 m). The carbon black was applied by helicopter using a dry applicator slung below a helicopter. The treatment effect was evaluated by control plot observations of melt and streamflow comparison before and after treatment. The ablation plot studies and runoff comparison with an adjacent watershed both indicated a 28 percent increase in ablation and meltwater runoff, respectively, for the months of July and August. The study indicates icefields could be used as cold-storage reservoirs for use in periods of critical water shortages.
Glycemic index and disease

It has been suggested that foods with a high glycemic index are detrimental to health and that healthy people should be told to avoid these foods. This paper takes the position that not enough valid scientific data are available to launch a public health campaign to disseminate such a recommendation. This paper explores the glycemic index and its validity and discusses the effect of postprandial glucose and insulin responses on food intake, obesity, type 1 diabetes, and cardiovascular disease. Presented herein are the reasons why it is premature to recommend that the general population avoid foods with a high glycemic index.
A method to track dataset reuse in biomedicine: filtered GEO accession numbers in PubMed central

Reusing research data has important potential benefits: generative science and efficient resource use. Tracking the reuse of research datasets would allow us to understand whether the potential benefits are indeed realized, enable recognition of investigators who produce, annotate, and share useful data, and inform data sharing and reuse initiatives, tools, and policies. Unfortunately, the lack of clear attribution practices for data make automated tracking of data reuse difficult. I present a method for tracking research data reuse that takes advantage of the community norms around gene expression microarray data sharing and the rich NCBI Entrez resources. Specifically, the full-text of papers stored in PubMed Central are queried for accession numbers of datasets archived in NCBI's Gene Expression Omnibus (GEO) repository. Studies known to have created microarray data are excluded through automated filters and guided manual curation. MeSH terms attached to the data creation and data reuse studies provide additional information for analysis. Finally, I extrapolate the findings to all of PubMed. Automated portions of this method have been implemented in python and are openly available. Although imperfect, this dataset is a valuable initial resource for research into patterns of data reuse.
Focal tuberculous osteomyelitis of the calcaneus secondary to direct extension from an infected retrocalcaneal bursa.

We report a case of focal tuberculous involvement of the posterior margin of the calcaneus with preservation of the articular margin. The route of infection was direct extension through tuberculous retrocalcaneal bursitis, a rare and atypical pathogenesis. Magnetic resonance imaging was helpful in ruling out neoplasm and in limiting the diagnosis to an inflammatory infectious process. (J Am Podiatr Med Assoc 95(3): 285–290, 2005)
Cerebral microvascular endothelium and the pathogenesis of neurodegenerative diseases.

Diseases of the central nervous system (CNS) pose a significant health challenge, but despite their diversity, they share many common features and mechanisms. For example, endothelial dysfunction has been implicated as a crucial event in the development of several CNS disorders, such as Alzheimer disease, Parkinson disease, amyotrophic lateral sclerosis, multiple sclerosis, human immunodeficiency virus (HIV)-1-associated neurocognitive disorder and traumatic brain injury. Breakdown of the blood–brain barrier (BBB) as a result of disruption of tight junctions and transporters, leads to increased leukocyte transmigration and is an early event in the pathology of these disorders. The brain endothelium is highly reactive because it serves as both a source of, and a target for, inflammatory proteins and reactive oxygen species. BBB breakdown thus leads to neuroinflammation and oxidative stress, which are implicated in the pathogenesis of CNS disease. Furthermore, the physiology and pathophysiology of endothelial cells are closely linked to the functioning of their mitochondria, and mitochondrial dysfunction is another important mediator of disease pathology in the brain. The high concentration of mitochondria in cerebrovascular endothelial cells might account for the sensitivity of the BBB to oxidant stressors. Here, we discuss how greater understanding of the role of BBB function could lead to new therapeutic approaches for diseases of the CNS that target the dynamic properties of brain endothelial cells.
Parameters tell the design story: ideation and abstraction in design optimization

We report qualitative findings from interviews and observations detailing how professionals generate and evaluate design ideas using design optimization tools. We interviewed 18 architects and manufacturing design professionals. We frame our findings using the Geneplore model of creative cognition and classify examples of ideation and abstract design thinking arising from optimization workflows. Contrary to our expectations, we found that the computed optimum was often used as the starting point for design exploration, not the end product. We also found that parametric models, plus their associated parameters and simulations serve as an alternate, highly valued form of design documentation distinct from engineering schematics.