cssi/SciSciGPT-SciSciNet huggingface dataset:
Effects of UV exposure and thermal history on properties of a preimidized photosensitive polyimide

The structure and properties of a preimidized photosensitive polyimide (Probimide PSPI, a copolyimide of benzophenonetetracarboxylic dianhydride with alkyl groups substituted aromatic diamines) were studied with variations of UV exposure energy and bake temperature by means of wide angle X-ray diffraction, dynamic mechanical thermal analysis, stress-strain analysis, and residual stress analysis. The X-ray diffraction patterns patterns indicate that the PSPI is amorphous in the solid state. The Tg was 378°C ∼ 410°C, depending upon the thermal history over the range of 350°C ∼ 400°C. At the glass transition region, the dynamic storage modulus E′ was very sensitive to both i-line exposure energy and thermal history. However, the mechanical stress-strain behavior at room temperature was primarily dependent on the thermal history. The mechanical properties were 2.6 GPa ∼ 2.9 GPa Young's modulus, 131 MPa ∼ 168 MPa tensile strength, 10% ∼ 12% yield strain, and 16% ∼ 74% elongation at break, depending upon the baking or annealing. These dynamic and static mechanical properties indicate that on the PSPI backbone, crosslinks are formed thermally as well as photochemically. The thermal crosslinks might be formed through thermal liberation of the labile alkyl groups of aromatic diamine moieties and subsequent coupling of the radicals. The thermal degradation was also evidenced in the mechanical properties degraded by baking above 375°C or annealing above 350°C. In addition, during baking and cooling, the residual stress was dynamically measured on Si wafers as a function of temperature. The stress at room temperature was 48 MPa ∼ 52 MPa for the PSPI films baked at 350°C or 400°C, regardless of i-line exposure.
Ultra-low voltage VLSI: are we there yet?

Aggressively scaled supply voltage has been touted as one of the most powerful mechanisms for improving reliability and reducing power consumption in nanometer technologies. Sophisticated adaptive power management techniques vary supply voltage from nominal to ultra-low values to implement adaptive VLSI systems that gracefully respond to varying workload demands for improved energy efficiency. Unfortunately, ultra-low voltage (sub-volt for current technologies) operation has been constrained by performance limitations. In this paper, the current state of low-voltage VLSI design is evaluated; techniques for maintaining acceptable throughputs at ultra-low voltages are reviewed; and trends and prospects for ultra-low voltage VLSI systems are presented.
Photomediated Solid-State Cross-Linking of an Elastin-Mimetic Recombinant Protein Polymer

Solid-state cross-linking of elastin-mimetic fibers was investigated. Through available lysine residues, an elastin-mimetic protein polymer, poly((Val-Pro-Gly-Val-Gly)4(Val-Pro-Gly-Lys-Gly))39, was modified to incorporate an acrylate moiety. The degree of acrylate functionalization could be varied by changing the reactant ratio of anhydride to elastin. Acrylate modified elastomeric (AME) proteins were associated with lower inverse transition temperatures than the unmodified recombinant protein. The inverse transition temperature in turn dictated the temperature for fiber formation. Fibers and fabric samples of AME were prepared by electrospinning at appropriate temperatures and cross-linked by visible- light-mediated photoirradiation. Fibers in the diameter range of 300 nm-1.5 Im were produced. Fabrics were found to have an average pore size of 78 Im. The occurrence of cross-linking was confirmed by 13 C solid-state NMR with a commensurate increase in modulus.
Role of nerve growth factor in experimental autoimmune encephalomyelitis.

The expression of neural regulatory molecules by immune cells that infiltrate the nervous system upon injury may be a mechanism for cross-regulation between the nervous system and the immune system. Several lines of evidence implicate nerve growth factor (NGF) signaling through its receptors (TrkA and p75NGFR) as a potential source of communication between the two systems. We observed changes in NGF mRNA expression and protein secretion by T lymphocytes polarized toward the Th2 phenotype. The presence of NGF did not affect T cell proliferation or cytokine production in vitro. Mice treated with NGF by i. p. injection following induction of experimental autoimmune encephalomyelitis, an inflammatory, demyelinating disease of the central nervous system, showed a delayed onset of disease and lower clinical scores during the course of disease. These data suggest a role for NGF signaling in the regulation of the immune response, possibly by enhancing sympathetic innervation of lymphoid tissues.
What Are the Correlates of Interdisciplinary Research Impact? The Case of Corporate Governance Research

We explore the concept of interdisciplinary research impact and better understand what factors might be associated with it. Using the field of corporate governance research as a case study and linking our research impact concept to a novel measure of scholarly citation rates, we seek to understand why some corporate governance scholars are cited more than others. We first developed a comprehensive ranking of the top-100 scholars cited for their research in corporate governance and then compared that “high-impact” group with scholars who had published governance research that was not yet cited. We hypothesized that indicators from the social network perspective would be predictive of interdisciplinary research impact. Our data largely supported our hypotheses using this new and improved measure of research impact, and robustness tests also supported our results.
Physiological responses to social and cognitive challenges in 8-year olds with a history of prenatal cocaine exposure.

Cocaine-exposed infants have been found to have altered arousal responses but little is known about such responses in later childhood. Physiological responses to stressors were used to assess the arousal modulation of school-aged, cocaine-exposed children (n = 73) and two contrast groups, socioeconomically-matched controls (n = 58) and children with behavioral disturbance (n = 35). The behaviorally disturbed group had the highest heart rate across conditions but demonstrated a pattern of hyporesponsiveness to the stressors. They had the smallest decrement in skin conductance response at baseline and the least recovery of skin conductance response following exposure to stressors. Cocaine-exposed children demonstrated greater acceleratory responses to the stressors as indexed by their skin conductance level and were intermediate between the socioeconomically-matched controls and children with behavioral disturbance in recovery of skin conductance response following stressors. Altered arousal responses associated with prenatal cocaine exposure persisted into middle childhood but were different from those found in behaviorally disturbed children. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 50: 251–265, 2008.
Self-powered sensors

One of the problems associated with miniaturization and portability of sensors is the power supply. Power supplies, such as batteries, are difficult to miniaturize and require a sensor design that allows for easy replacement or recharging. This review describes the field of self-powered sensing, where the sensor itself provides the power for the sensing device. Most self-powered-sensing strategies employ either nuclear energy conversion or electrochemical energy conversion. Nuclear energy conversion is employed for radioisotope or nuclear reactor sensing. Electrochemical energy conversion is employed for chemical and biological sensing. This review details the common strategies for self-powered nuclear, chemical, and biological sensing and discusses the future of the technology.
Cleavage Site for Sterol-regulated Protease Localized to a Leu-Ser Bond in the Lumenal Loop of Sterol Regulatory Element-binding Protein-2

A sterol-regulated protease initiates release of the NH2-terminal segments of sterol regulatory element-binding proteins (SREBPs) from cell membranes, thereby allowing them to enter the nucleus and to stimulate transcription of genes involved in the uptake and synthesis of cholesterol and fatty acids. Using SREBP-2 as a prototype, we here identify the site of sterol-regulated cleavage as the Leu522-Ser523bond in the middle of the 31-residue hydrophilic loop that projects into the lumen of the endoplasmic reticulum and nuclear envelope. This site was identified through use of a vector encoding an SREBP-2/Ras fusion protein with a triple epitope tag that allowed immunoprecipitation of the cleaved COOH-terminal fragment. The NH2 terminus of this fragment was pinpointed by radiochemical sequencing after replacement of selected codons with methionine codons and labeling the cells with [35S]methionine. Alanine scanning mutagenesis revealed that only two amino acids are necessary for recognition by the sterol-regulated protease: 1) the leucine at the cleavage site (leucine 522), and 2) the arginine at the P4 position (arginine 519). These define a tetrapeptide sequence, RXXL, that is necessary for cleavage. Cleavage was not affected when the second transmembrane helix of SREBP-2 was replaced with the membrane-spanning region of the low density lipoprotein receptor, indicating that this sequence is not required for regulation. Glycosylation-site insertion experiments confirmed that leucine 522 is located in the lumen of the endoplasmic reticulum. We conclude that the sterol-regulated protease is a novel enzyme whose active site faces the lumen of the nuclear envelope, endoplasmic reticulum, or another membrane organelle to which the SREBPs may be transported before cleavage.
Comparison of Methods Used for Forecasting Solar Radiation

This paper will present and evaluate a neural network-based approach to predicting solar radiation for a given site. This data is necessary to create valid decisions as to when to use other resources to generate energy in the micro-grid structure proposed for Smart Grid
Presurgical neuropsychological testing predicts cognitive and seizure outcomes after anterior temporal lobectomy

We sought to determine significant predictors of seizure and cognitive outcome following surgery for epilepsy. Participants included 41 patients who had undergone anterior temporal lobectomy (ATL). Higher presurgical verbal/language scores and lower nonverbal memory scores were predictive of seizure-free status following ATL. Overall, the presurgical predictors were 93% accurate in discriminating between seizure-free and non-seizure-free patients postsurgery. Surgery in the nondominant-for-language hemisphere was predictive of higher postsurgical verbal/language and verbal memory scores. Higher presurgical visual/construction, nonverbal memory, and verbal/language scores were predictive of better postsurgical verbal/language functioning. Better presurgical verbal/language functioning was predictive of the same skills postsurgically as well as visual/construction outcomes. Exploratory analyses in a subset of participants (n = 25) revealed that dominant and nondominant intracarotid amobarbital (Wada) memory scores added unique variance only for predicting nonverbal memory following ATL. Presurgical neuropsychological testing provides significant and unique information regarding postsurgical seizure freedom and cognitive outcome in patients who have undergone ATL.
Cancer associated haemolytic uraemic syndrome developing prior to treatment with cytotoxic agents

The haemolytic uraemic syndrome has been reported in children and adults with neoplasias treated with mitomycin C and occasionally in adults prior to chemotherapeutic treatment, but it has not been reported in a child prior to the use of cytotoxic drugs. This case report concerns the development of the haemolytic uraemic syndrome in a 7-year-old male child with a metastatic hepatocellular carcinoma. The child had persisting haemolysis and renal impairment, and died three weeks after presentation. Though our experience with similar tumours suggested the outlook would be poor, we had hoped to provide palliative chemotherapy. This proved impossible as optimal chemotherapy could not be used because of the renal impairment.
A procedure for estimating lateral variations from low-frequency eigenspectra data

Summary. Expressions are derived for the zeroth and first moments of an isolated normal mode multiplet in the presence of rotational anisotropy, lateral heterogeneity and attenuation. It is demonstrated that, to first order, the zeroth moment is independent of the heterogeneity and the first moment is a linear functional of the heterogeneity. The location of the multiplet, defined in terms of the ratio of the first moment to the zeroth moment, is used to set up a linear inverse problem for lateral variations. The approximations employed in deriving the differential kernels are uniformly valid for all angular orders. In addition, formula for the differential kernels asymptotically valid in the limit of large angular order are developed, and the correspondence between these formulae and the geometrical optics approximation is established. It is shown that, in the limit of weak heterogeneity and large angular order, the location of the multiplet is the average of the local perturbation to the eigenfrequency over the great circular path containing the source and receiver.
A combinatorial interpretation of the Legendre-Stirling numbers

The Legendre-Stirling numbers were discovered in 2002 as a result of a problem involving the spectral theory of powers of the classical second-order Legendre differential expression. Specifically, these numbers are the coefficients of integral composite powers of the Legendre expression in Lagrangian symmetric form. Quite remarkably, they share many similar properties with the classical Stirling numbers of the second kind which, as shown by Littlejohn and Wellman, are the coefficients of integral powers of the Laguerre differential expression. An open question regarding the Legendre-Stirling numbers has been to obtain a combinatorial interpretation of these numbers. In this paper, we provide such an interpretation.
Congenital posterior urethral valves in adult males.

Abstract Twenty-six cases of congenital urethral valvular obstruction in men ages twenty-one tosixty-seven are reported. The majority had irritative symptoms of the lower urinary tract associated with chronic prostatitis, and 10 complained of obstructive symptoms. Urinalysis was normal in 20, and intravenous pyelogram showed normal upper tracts in 22 cases and significant postvoiding residual urine in only 5. Voiding studies, particularly urodynamics, were the most valuable diagnostic tool. Chronic posterior urethritis and prostatitis were found in 85 per cent of the cases, and a 76-per cent incidence of moderate or severe fibrous bladder neck contracture occurred in patients over forty years of age.
Redox potentials and phosphorylative efficiency of mitochondria

Abstract In mitochondria which exhibit high P O ratios, > 5, P O ratios progressively increase during State 3 respiration. This is associated with progressive increases in the level of reduction of electron carriers, especially cytochrome C and flavin. With mitochondria whose P O ratio is 3 or less, all electron carriers are oxidized upon addition of ADP. Similarly with substrates of progressively decreasing redox potential, a parallel decrease in the steady-state level of reduction of the electron carriers also occurs. These data suggest that mitochondria, like chloroplasts, can phosphorylate efficiently only under conditions in which high levels of reduction of the electron carriers are maintained during State 3 respiration. These data are discussed in relation to the theory of the mechanism of phosphorylation previously proposed for chloroplasts.
Stellar calibration of the ROLO lunar radiometric reference

The Lunar Calibration program at the U.S. Geological Survey (USGS) in Flagstaff, AZ, provides the radiometric reference of the Moon as a source for calibration at reflected-solar wavelengths. To develop this capability, thousands of multispectral images of the Moon were acquired by the Robotic Lunar Observatory (ROLO) telescope imaging systems. During normal ROLO operations, 10 to 12 different stars were observed up to 15 times each night, primarily to derive atmospheric transmittance corrections for the Moon observations. But additionally, the ROLO telescope sensors are calibrated to the star Vega through a process of reduction of stellar images to absolute irradiances. A study of the ROLO stellar imaging characteristics for this purpose has led to development of an analytic model for the signal contained in the extended point spread function of the image data. This model is then applied as part of the standard data reduction procedures to generate corrections for individual star images. The resulting absolute stellar irradiance measurements allow development of a calibration history for the entire ROLO dataset, and by extension for the lunar models that constitute the lunar radiometric reference. This paper will discuss the image reduction techniques developed for calibration of the ROLO focal plane array sensors, and the implications of this development on the use of the Moon as a calibration reference source.
Seasonal patterns of viruses, bacteria and dissolved organic carbon in a riverine wetland

SUMMARY 1. Viral and bacterial abundances were studied in relation to environmental attributes over an annual period, for both planktonic and attached (sediment, aquatic macrophyte and submerged wood) habitats, in a riverine wetland. 2. Annual mean abundance of planktonic viruses ranged from 2.3 × 105−3.8 × 105 particles mL−1 and varied according to sampling site. Significant seasonal patterns in viral abundance were evident and appeared to be linked to variations in bacterial abundance, dissolved organic carbon and inorganic nutrients. 3. Annual mean abundance of viruses associated with surfaces ranged from 1.3 × 106 particles cm−2 on aquatic macrophytes to 1.1 × 107 particles cm−2 on wood and also showed seasonal patterns. The difference in viral dynamics among the different sites emphasizes the importance of considering habitat diversity within wetlands when examining microbial communities.
Effect of a mechanical stimulation bioreactor on tissue engineered, scaffold‐free cartilage

Achieving sufficient functional properties prior to implantation remains a significant challenge for the development of tissue engineered cartilage. Many studies have shown chondrocytes respond well to various mechanical stimuli, resulting in the development of bioreactors capable of transmitting forces to articular cartilage in vitro. In this study, we describe the production of sizeable, tissue engineered cartilage using a novel scaffold-free approach, and determine the effect of perfusion and mechanical stimulation from a C9-x Cartigen bioreactor on the properties of the tissue engineered cartilage. We created sizable tissue engineered cartilage from porcine chondrocytes using a scaffold-free approach by centrifuging a high-density chondrocyte cell-suspension onto an agarose layer in a 50 mL tube. The gross and histological appearances, biochemical content, and mechanical properties of constructs cultured in the bioreactor for 4 weeks were compared to constructs cultured statically. Mechanical properties were determined from unconfined uniaxial compression tests. Constructs cultured in the bioreactor exhibited an increase in total GAG content, equilibrium compressive modulus, and dynamic modulus versus static constructs. Our study demonstrates the C9-x CartiGen bioreactor is able to enhance the biomechanical and biochemical properties of scaffold-free tissue engineered cartilage; however, no additional enhancement was seen between loaded and perfused groups.
A nuclear-resonance study of local-moment fluctuations in CuMn☆

Abstract We have used 63Cu satellite resonances of host nuclei near Mn impurities to probe relaxation of the Mn moment in Cu Mn. In the range 1.2 –2.0 K (26–50 kOe) we are able to account for the satellite spin-lattice relaxation rates using a lowest-order perturbation treatment of the local-moment/conduction-electron exchange interaction with |Jϱ| = 0.20(2), in good agreement with the high-temperature (≁ 1200 K) NMR results of Walstedt and Warren.
Deformation processing of bonded Cu-15% Nb sheets

This study investigated the feasibility of diffusion bonding a stack of heavily cold-rolled Cu-15% Nb sheets at a temperature below which pronounced coarsining of the Nb filaments occurred in the cold-worked sheets. Subsequent cold-rolling of the stack of diffusion bonded sheets to produce additional strengthening in the resultant sheet was used as a measure of the success of the diffusion bonding treatment
Multiplicity distribution at 200 GeV and the inverse-square falloff

Abstract The deviation of the multiplicity distribution at 200 GeV from the n−n behavior is explained by a consideration of the exponential damping in momentum transfer for double diffractive excitation processes. From a fit to σ(nc) at 200 GeV, we predict the energy dependences of σ(nc), 〈nc〉 and 〈nc(nc−1)〉. The agreement with data is good.
The Weakly Coordinating Trichloromethanesulfonate Anion: NQR Comparison of Its Coordinating Abilities via Oxygen with Those of the Chloroacetate Ions

Ionic and covalent derivatives of the chlorine analogue of the nonbasic, weakly coordinating triflate ion, Cl3CSO3(-) or "trichlate" ion, have been prepared and compared with the corresponding more strongly coordinated chloroacetates, Cl(x)CH(3-x)CO(2)M (x = 1-3), using 35Cl NQR (nuclear quadrupole resonance) spectroscopy. The (35)Cl NQR frequencies of all types of derivatives are sensitive to the nature of the metal ion or Lewis acid and are most sensitive in the case of monochloroacetates. In covalent (including zirconocene) derivatives, the average NQR frequencies fall as the Pauling electronegativity of M falls. The results for ionic derivatives contrast with previous results for ionic hexachlorometalates: the average (35)Cl NQR frequencies drop sharply as the ionic radius of the group 1 cation increases. Ab initio Gaussian 98 computations at the B3LYP/6-311++G(3df,3pd) level on isolated XCH2CO2M (M = Li, Na, K; X = F, Cl) molecules duplicate this trend, showing increasing polarization of the C-Cl bond and smaller electric field gradients for larger group 1 ions; the relevance of this to the solid state polymerization of chloroacetates (Herzberg, O.; Epple, M. Eur. J. Inorg. Chem. 2001, 1395-1406) is discussed. We have prepared the dihydrate and monohydrate of trichlic acid, Cl3CSO3H. Although trichlates have the highest average NQR frequencies of any of these salts, the NQR frequencies of trichlic acid dihydrate are anomalously lower than those of trichloroacetic acid, which suggests that it is a strong acid, ionized in the solid state to H5O2+ and Cl3CSO3(-) ions.
Test beam results from the CLEO III LiF-TEA RICH

Abstract The CLEO collaboration is preparing a major upgrade of its present detector including a RICH detector for particle identification. This subdetector system follows the ‘proximity focussing’ design and uses Lithium Fluoride (LiF) crystal radiators and MWPCs filled with a CH 4 /TEA gas mixture. Part of the radiator crystals will have the new ‘sawtooth’ geometry. We have tested the first two of the 30 detector modules together with the first radiator crystals in a muon halo beam at Fermilab. For the measurement of the Cherenkov angle we obtain a single photon measurement error of 13.5 mrad for the conventional planar radiator. With 14 detected photons we find a resolution per track of 4.5 mrad. In the first measurement ever of a ‘sawtooth’ radiator we achieve a resolution of 11.8 mrad for single photons and 4.8 mrad per track for 12.3 detected photons with a reduced geometric acceptance. These results fulfill CLEO III requirements.
Psychometric Properties of the Obsessive Compulsive Inventory: Child Version in Children and Adolescents with Obsessive–Compulsive Disorder

The psychometric properties of the Obsessive Compulsive Inventory–Child Version (OCI-CV) were examined in ninety-six youth with a primary/co-primary diagnosis of obsessive–compulsive disorder (OCD). A confirmatory factor analysis revealed an acceptable model of fit with factors consisting of doubting/checking, obsessing, hoarding, washing, ordering, and neutralizing. The internal consistency of the OCI-CV total score was good, while internal consistency for subscale scores ranged from poor to good. The OCI-CV was modestly correlated with obsessive–compulsive symptom severity on the Children’s Yale-Brown Obsessive Compulsive Scale (CY-BOCS) Severity Scale, as well as with clinician-reported OCD severity. All OCI-CV subscales significantly correlated with the corresponding CY-BOCS Symptom Checklist dimension. The OCI-CV significantly correlated with child-reported depressive symptoms and OCD-related functional impairment, but was not significantly correlated with parent-reported irritability or clinician-reported overall functioning. Taken together, these data suggest the psychometric properties of the OCI-CV are adequate for assessing obsessive–compulsive symptom presence among youth with OCD.
The Adverse Effect of Spasticity on 3-Month Poststroke Outcome Using a Population-Based Model

Several devices and medications have been used to address poststroke spasticity. Yet, spasticity's impact on outcomes remains controversial. Using data from a cohort of 460 ischemic stroke patients, we previously published a validated multivariable regression model for predicting 3-month modified Rankin Score (mRS) as an indicator of functional outcome. Here, we tested whether including spasticity improved model fit and estimated the effect spasticity had on the outcome. Spasticity was defined by a positive response to the question "Did you have spasticity following your stroke?" on direct interview at 3 months from stroke onset. Patients who had expired by 90 days (n = 30) or did not have spasticity data available (n = 102) were excluded. Spasticity affected the 3-month functional status (β = 0.420, 95 CI = 0.194 to 0.645) after accounting for age, diabetes, leukoaraiosis, and retrospective NIHSS. Using spasticity as a covariable, the model's R (2) changed from 0.599 to 0.622. In our model, the presence of spasticity in the cohort was associated with a worsened 3-month mRS by an average of 0.4 after adjusting for known covariables. This significant adverse effect on functional outcomes adds predictive value beyond previously established factors.
Industrial Earthquake Preparedness in Shizouka and the Role of the Prefectural Government

Abstract The Shizuoka Prefectural Office in Japan plays an important role in promoting earthquake emergency preparedness among its industries. In addition to implementing regulatory requirements and enacting new regulations as necessary, the Prefectural Office also provides significant guidance to industry. This includes making publications available and periodic surveys of the status of industrial emergency preparedness. A pharmaceutical company in the prefecture has developed an impressive earthquake preparedness program and hazard reduction techniques. This program addresses both primary and secondary effects of earthquakes.
A pseudospectral method for two-point boundary value problems

Pseudospectral collocation is employed for the numerical solution of nonlinear two-point boundary value problems with separated end conditions. Second-order finite difference schemes are used as preconditioners for the spectral calculation, and a solution of the discretized equations is obtained using versions of the defect correction principle. The method and a variant based on an adaptive grid technique are tested on a variety of sample problems and are shown to provide high accuracy with low storage requirements.
Computational techniques for determining nonrigid motion of blood from medical images

In this work, we present results from a new formulation for determining certain class of optical flow fields. The formulation is particularly efficient, as the flow field is either a global 90 degrees rotation applied to the gradient of a scalar function, or is identical to the gradient of a scalar function. The formulation is general: it is applicable whenever the velocity field is incompressible, or irrotational. We are interested in the study of nonrigid motion of incompressible fluids, and as such will restrict most of the discussions to the case of divergence-free velocity fields. Starting from the conservation of mass principle, we derive a motion constraint equation for x-ray projection pictures, a special case of which is shown to be the Horn and Schunck's optical flow constraint. It is shown that if specific criteria are met, in addition to the normal component of the velocity field, the tangential component is recoverable, without the need for smoothness. An algorithm is presented to illustrate this. The techniques are applied to synthetic images, as well as contrast-injected x-ray images of flowing fluid, in a cylindrical phantom.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Europa's Icy Shell: A Bridge Between Its Surface and Ocean

Europa, a Moon-sized, ice-covered satellite of Jupiter, is second only to Mars in its astrobiological potential. Beneath the icy surface, an ocean up to 150 km deep is thought to exist, providing a potential habitat for life,and a tempting target for future space missions. The Galileo mission to the Jovian system recently ended, but there are already long-range plans to send much more capable spacecraft,such as the proposed Jupiter Icy Moons Orbiter (JIMO), to take a closer look at Europa and her siblings, Ganymede and Callisto, some time in the next two decades. Europak outer icy shell is the only interface between this putative ocean and the surface, but many aspects of this shell are presently poorly understood; in particular, its composition, thickness, deformational history, and mechanical properties. To discuss the ice shell and our current understanding of it, 78 scientists from the terrestrial and planetary science communities in the United States and Europe gathered for a 3-day workshop hosted by the Lunar and Planetary Institute in Houston in February. A key goal was to bring researchers from disparate disciplines together to discuss the importance and limitations of available data on Europa with a post-Galileo perspective. The workshop featured 2 days of reviews and contributed talks on the composition, physical properties, stratigraphy, tectonics, and future exploration of the ice shell and underlying ocean. The final morning included an extended discussion period, moderated by a panel of noted experts, highlighting outstanding questions and areas requiring future research.
The Development of Policy Thinking in Adolescence

This article identifies four fundamental modes of thought employed in the cognition of policy problems. These modes of thought are moral, cause-effect, sociocentric, and imaginative. Nine variants of these four forms are described and investigated among a small sample of adolescents. The maturation of these forms of thought appears limited during adolescence, and change is not well predicted by the respondent's level of politicization. The article concludes with some speculations about the structure of socialization theory as it relates to the development of fundamental forms of political thinking.
Reversible post-exposure yellowing of weathered polymers

Abstract The commonly observed effect of weathered polymer samples continuing to change color in the dark was studied in some detail for polycarbonate, styrene–acrylonitrile copolymer (SAN), and various combinations with SAN–polybutadiene rubber graft (SRG) copolymer. All of the formulations became more yellow upon storage in the dark after accelerated weathering, and all behaved very similarly. There was a fairly rapid shift of 1–2 b units (as defined in CIELAB color space) over the first two weeks followed by a slower, linear shift that continued for many months. This amount of color shift is enough to be visible to the eye in side-by-side comparisons. Most of the additional color generated in the dark could be bleached by exposing the samples to sunlight through a south-facing window. The samples usually reached the original color after 2–4 days of window exposure. Putting the samples back in the dark caused the yellowing to start up again, although the rapid yellowing often was not as much as the first time. Samples aged under natural conditions outdoors also underwent a small color shift upon storage for 5 months and substantial color shifts after two years. The results are consistent with the photo–thermal equilibrium between Z – E isomers as suggested in the literature, although some aspects remain unexplained.
Lucigenin chemiluminescence as a probe for measuring reactive oxygen species production in Escherichia coli

Abstract Addition of oxygen to whole cells of Escherichia coli suspended in the presence of the chemiluminescent probe bis-N-methylacridinium nitrate (lucigenin) resulted in a light emission increase of 200% of control. Addition of air to cells showed a chemiluminescent response far less than the response to oxygen. The redox cycling agents paraquat and menadione, which are known to increase intracellular production of O2− and H2O2, were also found to cause a measurable increase in lucigenin chemiluminescence in E. coli cells when added at concentrations of 1 and 0.1 m m , respectively. The oxygen-induced chemiluminescent response was not suppressed by extracellularly added superoxide dismutase or catalase. Further, the lucigenin-dependent chemiluminescent response of aerobically grown E. coli to oxygen was significantly greater than that of cells grown anaerobically. Heat-killed cells showed no increase in chemiluminescence on the addition of either oxygen, paraquat, or menadione. These results show that lucigenin may be used as a chemiluminescent probe to demonstrate continuous intracellular production of reactive oxygen metabolites in E. coli.
Fine-scale temperature fluctuation and modulation of Dirofilaria immitis larval development in Aedes aegypti.

Abstract We evaluated degree-day predictions of Dirofilaria immitis development (HDU) under constant and fluctuating temperature treatments of equal average daily temperature. Aedes aegypti mosquitoes were infected with D. immitis microfilariae and parasite development was recorded at set time points in dissected mosquitoes. Time to L3 development in Malpighian tubules and detection in mosquito heads was shorter for larvae experiencing a daily regime of 19 ± 9 °C than larvae at constant 19 °C; larval development rate in Malpighian tubules was slower in fluctuating regimes maintained above the 14 °C developmental threshold than larvae under constant temperatures. We showed that hourly temperature modeling more accurately predicted D. immitis development to infective L3 stage. Development time differed between fluctuating and constant temperature treatments spanning the 14 °C development threshold, implicating a physiological basis for these discrepancies. We conclude that average daily temperature models underestimate L3 development—and consequently dog heartworm transmission risk—at colder temperatures, and spatiotemporal models of D. immitis transmission risk should use hourly temperature data when analyzing high daily temperature ranges spanning 14 °C.
Alternative splicing regulation during C. elegans development: splicing factors as regulated targets.

Alternative splicing generates protein diversity and allows for post-transcriptional gene regulation. Estimates suggest that 10% of the genes in Caenorhabditis elegans undergo alternative splicing. We constructed a splicing-sensitive microarray to detect alternative splicing for 352 cassette exons and tested for changes in alternative splicing of these genes during development. We found that the microarray data predicted that 62/352 (∼18%) of the alternative splicing events studied show a strong change in the relative levels of the spliced isoforms (>4-fold) during development. Confirmation of the microarray data by RT-PCR was obtained for 70% of randomly selected genes tested. Among the genes with the most developmentally regulated alternatively splicing was the hnRNP F/H splicing factor homolog, W02D3.11 – now named hrpf-1. For the cassette exon of hrpf-1, the inclusion isoform comprises 65% of hrpf-1 steady state messages in embryos but only 0.1% in the first larval stage. This dramatic change in the alternative splicing of an alternative splicing factor suggests a complex cascade of splicing regulation during development. We analyzed splicing in embryos from a strain with a mutation in the splicing factor sym-2, another hnRNP F/H homolog. We found that approximately half of the genes with large alternative splicing changes between the embryo and L1 stages are regulated by sym-2 in embryos. An analysis of the role of nonsense-mediated decay in regulating steady-state alternative mRNA isoforms was performed. We found that 8% of the 352 events studied have alternative isoforms whose relative steady-state levels in embryos change more than 4-fold in a nonsense-mediated decay mutant, including hrpf-1. Strikingly, 53% of these alternative splicing events that are affected by NMD in our experiment are not obvious substrates for NMD based on the presence of premature termination codons. This suggests that the targeting of splicing factors by NMD may have downstream effects on alternative splicing regulation.
Therapeutic role of mammalian target of rapamycin (mTOR) inhibition in preventing epileptogenesis

Traditionally, medical therapy for epilepsy has aimed to suppress seizure activity, but has been unable to alter the progression of the underlying disease. Recent advances in our understanding of mechanisms of epileptogenesis open the door for the development of new therapies which prevent the pathogenic changes in the brain that predispose to spontaneous seizures. In particular, the mammalian target of rapamycin (mTOR) signaling pathway has recently garnered interest as an important regulator of cellular changes involved in epileptogenesis, and mTOR inhibitors have generated excitement as potential antiepileptogenic agents. mTOR hyperactivation occurs in tuberous sclerosis complex (TSC), a common genetic cause of epilepsy, as a result of genetic mutations in upstream regulatory molecules. mTOR inhibition prevents epilepsy and brain pathology in animal models of TSC. mTOR dysregulation has also been demonstrated in a variety of other genetic and acquired epilepsies, including brain tumors, focal cortical dysplasias, and animal models of brain injury due to status epilepticus or trauma. Indeed, mTOR inhibitors appear to possess antiepileptogenic properties in animal models of acquired epilepsy as well. Thus, mTOR dysregulation may represent a final common pathway in epilepsies of various causes. Therefore, mTOR inhibition is an exciting potential antiepileptogenic strategy with broad applications for epilepsy and could be involved in a number of treatment modalities, including the ketogenic diet. Further research is necessary to determine the clinical utility of rapamycin and other mTOR inhibitors for antiepileptogenesis, and to devise new therapeutic targets by further elucidating the signaling molecules involved in epileptogenesis.
Slums in developing countries: New evidence for Indonesia

Abstract This paper uses Indonesian data to provide new evidence on the links between household and dwelling characteristics in a developing country. The results show that higher income and education lead to occupancy of dwellings with better structural characteristics, an effect that is reinforced if the household is large and contains few children. Religion also matters, with non-Buddhist households occupying dwellings with worse structural characteristics. The directions of these effects are mostly consistent with separate estimates of household bid-rent functions, which show that willingness-to-pay for better housing attributes rises with income and education.
A densitometric nondestructive microassay for DNA quantitation

Abstract A nondestructive assay for small quantities of nonradioactive DNA has been developed. Submicroliter volumes of DNA samples of concentrations as low as 10 μg/ml in 10 m m Tris, pH 8, containing 10 μg/ml ethidium bromide are photographed in 1-μl microcapillary tubes on a near-uv transilluminator. The negatives are scanned with a densitometer, producing a sharp peak for each capillary; samples whose peak heights show apparent linearity with DNA content are compared to the linear portion of a standard curve constructed from DNA samples of known concentrations. The samples may be recovered undamaged, as introduction into capillaries and illumination for photography do not introduce nicks into the DNA. The DNA samples may be of heterogeneous molecular weight, but all DNAs should be of similar base composition and in the same buffer. Traces of phenol do not interfere with the determination.
A POINT STOCHASTIC MODEL FOR CONTINENTAL DROUGHTS / Modèle stochastique ponctuel pour les sécheresses continentales

Abstract A two-level point stochastic model is used to represent the daily rainfall occurrences in the midwestern United States. The primary level corresponds to the generating mechanism of the rainfall occurrences such as fronts and thunderstorm clouds. The secondary level corresponds to the actual rainfall occurrences. The persistence of the rainfall occurrences is basically due to the persistence of the rainfall generating mechanisms. The persistence of the actual rainfalls can be explained in terms of their clustering around the rainfall generating mechanism. Based on these physical facts a point stochastic cluster model of the Neyman-Scott type is constructed for the rainfall occurrences around the Great Lakes region of the North American continent. This two-level point stochastic model utilizes the meteorological characteristics of the rainfall generating mechanisms for the simulation of the probabilities of dry and wet sequences. The probabilities of drought lengths and the return period of rainfal...
The spectral property of time delay

Abstract This paper discusses the spectral property of time delay. If one considers the scattering by a potential v , then the spectral property is the statement that the trace of the time-delay operator is proportional to the change in state density produced by the interaction v . We give a new and elementary proof of this result. As a consequence it is shown that Levinson's theorem is implied by the spectral property.
Reconciling Technologic and Family Care in Critical-Care Nursing

An interpretive phenomenologic study examined the practice of 130 nurses caring for families in critical care units (CCUs) using group interviews and multiple observations of practice. More than 100 examples of care of the family in CCU served as text for interpretation. A range of practice with families was observed, including practice focused on biomedical management of the patient and care that expertly incorporated the family while at the same time addressing the complex, technologic care of the critically ill. Reciprocal clinical knowledge transfer is needed among nurses at the bedside who are working in family practice and nurses who are skilled and knowledgeable about family interventions.
Experiences of using a dependence profiler to assist parallelization for multi-cores

We show how to use a data-dependence profiling tool called DProf, which can be utilized to assist parallelization for multi-core systems. DProf is based on an optimizing compiler and uses reference runs to emit information on runtime dependences between various memory accesses within a loop. The profiler not only marks the dependent statements and the accesses but also emits details regarding the percentage of time the dependences are encountered - the percentage being taken over the loop iteration size. Though DProf has been primarily built to capture opportunities for speculative thread-level parallelism, it has been found that the report generated by the DProf can be utilized very effectively in detecting and parallelizing complex code. To demonstrate this, we have taken two complex benchmarks - 435.gromacs and 437.leslie3d from the SPECfp CPU2006 suite and show how they can be parallelized effectively using DProf as an assist. To the best of our knowledge none of the existing parallelizing compilers can detect and parallelize all the instances reported in this work. We find that by using DProf we are able to parallelize these benchmarks very effectively for IBM P5+ and P6 multi-core systems. We have parallelized the benchmarks using OpenMP leading to speedups up to 2.6x. Also, due to the detailed reporting by DProf, we could cut down on our parallelization development effort significantly by concentrating on portions of the code that require attention. DProf can also be used to identify applications, where applying parallelization may lead to regression in performance. This allows the developers to discard applications or parts of it quickly, which may not lead to performance improvements when deployed on multi-cores. Thus, a data dependence profiler like DProf can act as an excellent assist mechanism to move applications to multi-cores in an effective way.
Electrochemical corrosion testing of fasteners in extracts of treated wood

A recent change in wood preservatives has highlighted the need for a rapid, quantitative test to measure the corrosion rates of metals in contact with treated wood that could be used to evaluate new fasteners or new wood preservatives. A new method was developed where polarisation resistance tests were conducted on fasteners exposed to a water extract of wood treated with alkaline copper quaternary (ACQ). Good correlation was found between the corrosion rates using this new method and previous one year exposure data for carbon steel, hot-dip galvanized and electroplated galvanized fasteners. These data suggest that polarisation tests run in wood extract may be an effective, rapid test method to evaluate new fasteners or wood preservatives.
Parsimonious prediction of Wechsler Memory Scale, Fourth Edition scores: Immediate and delayed memory indexes

Research on previous versions of the Wechsler Memory Scale (WMS) found that index scores could be predicted using a parsimonious selection of subtests (e.g., Axelrod & Woodard, 2000). The release of the Fourth Edition (WMS–IV) requires a reassessment of these predictive formulas as well as the use of indices from the California Verbal Learning Test–II (CVLT–II). Complete WMS–IV and CVLT–II data were obtained from 295 individuals. Six regression models were fit using WMS–IV subtest scaled scores—Logical Memory (LM), Visual Reproduction (VR), and Verbal Paired Associates (VPA)—and CVLT–II substituted scores to predict Immediate Memory Index (IMI) and Delayed Memory Index (DMI) scores. All three predictions of IMI significantly correlated with the complete IMI (r = .92 to .97). Likewise, predicted DMI scores significantly correlated with complete DMI (r = .92 to .97). Statistical preference was indicated for the models using LM, VR, and VPA, in which 97% and 96% of the cases fell within two standard errors o...
Regeneration in Alfalfa Tissue Culture: Characterization of Intracellular pH During Somatic Embryo Production by Solid-State P-31 NMR

The composition of phosphorus-containing compounds of intact lyophilized alfalfa tissue has been determined, in part, by solid-state (31)P nuclear magnetic resonance. The tissue (Medicago sativa L., cv Regen S; and some of its crosses) was grown in culture under both nonregenerating and regenerating conditions, the latter enhanced by the addition of specific amino acids. Analysis of the (31)P nuclear magnetic resonance spectra shows that regeneration is favored when metabolism occurs without the production of a low average intracellular pH.