cssi/SciSciGPT-SciSciNet huggingface dataset:
A Practitioner’s Guide to Prescribing Phenytoin for Adults with Intellectual Disabilities

We developed this phenytoin guideline using drug prescribing information and reviewing the available literature on relevant neuropsychiatric disorders in populations without intellectual disabilities because of the dearth of available literature on the population with intellectual disabilities. This guideline includes indications; contraindications; assessments prior to and during treatment; dosing with particular focus on dosing modifications required by drug–drug interactions, personal characteristics or genetic variants; and adverse drug reactions. The procedures contained in this guideline may not fully account for all of the possible risks of treatment in this population because of the limited studies available; thus, there will be a need to periodically update this guideline as new information becomes available. Nevertheless, we believe that this guideline provides a useful resource for clinicians who treat epilepsy in adult individuals with intellectual disabilities. A phenytoin drug utilization review that summarizes this guideline is described.
Palmitoylation of Neurofascin at a Site in the Membrane‐Spanning Domain Highly Conserved Among the L1 Family of Cell Adhesion Molecules

This report presents the first evidence that a member of the L1 family of nervous system cell-adhesion molecules is covalently modified by thioesterification with palmitate, and identifies a highly conserved cysteine in the predicted membrane-spanning domain as the site of modification. Neurofascin is constitutively palmitoylated at cysteine-1213 at close to a 1:1 molar stoichiometry. Kinetics of palmitate incorporation into neurofascin expressed in resting neuroblastoma cells indicate that the palmitate modification has the same turnover rate as the polypeptide chain and does not affect the protein stability of neurofascin. Palmitoylation of neurofascin expressed in dorsal root ganglion neurons is not required for delivery of neurofascin to the plasma membrane or targeting to axons. Palmitoylation also has no effect on ankyrin-binding activity of neurofascin, on the oligomeric state of neurofascin in solution, or on cell-adhesion activity of neurofascin expressed in neuroblastoma cells. A significant difference between native and C1213L neurofascin is that these proteins were localized in distinct fractions within a low-density membrane population enriched in signaling molecules. These results indicate a palmitate-dependent targeting of neurofascin to a specialized membrane microdomain.
Pulsed microdischarge, 121.6 nm VUV source with 40 watt peak power

A micro hollow cathode discharge VUV source, with time averaged power above 3 watts, and peak power above 40 watts is presented1. Such operation is achieved by driving the microdischarge (MD) in the arc mode where high electron densities and low discharge impedances exist. Improved theoretical estimations regarding the timescales of arc formation are presented. With typical electrical sources, the arc regime is associated with a collapse of the potential and poor coupling of energy. However, the pulsed driver utilized in this study features a low output impedance, thus sustaining a reasonable voltage across the MD while simultaneously delivering 10s of amperes when the arc mode is achieved. This allows for time averaged input power on the order of 550 watts. Gas mixtures such as Ar-H 2 (99.7%/0.3% by volume) have demonstrated strong VUV emission at Lyman-α (121.6 nm), with measured power levels exceeding 40 watts peak.
Spectral and Structural Characterization of 5,6-Chrysenequinone Diimine Complexes of Rhodium(III): Evidence for a pH-Dependent Ligand Conformational Switch

Rhodium(III) complexes containing 9,10-phenanthrenequinone diimine (phi) ligands have been broadly applied for the construction of DNA binding and recognition molecules, and more recently, derivatives containing the 5,6-chrysenequinone diimine (chrysi) ligand have been shown specifically to recognize base mismatches in DNA. Here the structural properties of [Rh(bpy)_2(chrysi)]Cl_3 and spectroscopic properties of derivatives are examined and compared to those of phi complexes of rhodium. Although similar in many respects, phi and chrysi complexes display distinctly different protonation behavior. The pK_a values of chrysi complexes are as much as 1 unit lower than analogous phi compounds, and visible spectra of the chrysi complexes differ markedly from the phi counterparts in acidic but not basic solution. This protonation behavior is traced to the presence of a steric clash between a proton on the aromatic ring of the chrysi ligand and the acidic immino proton of the metal complex. In avoidance of this steric clash, a significant disruption in the planarity of the chrysi ligand is evident crystallographically in the structure of [Rh(bpy)_2(chrysi)]Cl_3·3CH_3CN·2H_2O (triclinic crystal system, space group P1 (No. 2), Z = 2, a = 9.079(3) A, b = 10.970(3) A, c = 21.192(8) A, α = 86.71(3)°, β = 89.21(3)°, γ = 78.58(3)°, V = 2065.4(12) A^3). Phi complexes, lacking the additional aromatic ring, require no similar distortion from ligand planarity. NMR spectra support this pH-dependent structural distortion for the chrysi complex. Rhodium complexes of chrysenequinone diimine, therefore, not only represent new DNA binding molecules targeted to mismatches but also provide an illustration of a pH “gated” ligand conformational switch.
Timing of factor VIIa in liver transplantation impacts cost and clinical outcomes.

Study Objective To investigate the clinical and economic outcomes associated with the use of recombinant factor VIIa (rFVIIa) in perioperative liver transplantation (LT). Design Retrospective review. Setting Academic medical center. Patients A total of 63 adults who underwent LT between January 2000 and September 2008 and received rFVIIa prior to or during the procedure. Using a propensity-scoring method, these patients were matched in a 1:2 ratio with 120 controls. Measurements and Main Results Of the 473 patients who received any LT during the study period, 63 (13%) received rFVIIa and were matched with propensity score matched controls at a ratio of approximately 1:2. Of those who received rFVIIa, 27 (43%) received preemptive administration and 14 (22%) received intraoperative administration. (The remaining 22 patients received rFVIIa outside of a 12-hour window of time before or after surgery.) Clinical outcomes were similar between the preemptive and the control groups, although patients in the control group had a shorter length of stay in the intensive care unit (ICU) and incurred fewer expenses. Compared with both the preemptive and the control groups, patients who received rFVIIa intraoperatively required more blood products, longer stays in the ICU, and incurred higher costs. They also had poorer graft survival and decreased overall survival rates at 30 days and 1 year. Conclusion Intraoperative administration of rFVIIa in LT was associated with higher blood product use, lower graft and patient survival rates, longer ICU stays, and higher overall costs compared with preemptive administration. The use of preemptive rFVIIa in select high-risk LT patients may prevent the development of poor clinical outcomes and may be more cost effective compared with intraoperative administration.
Cerebral amyloid angiopathy as cause of convexity SAH in elderly.

Background Spontaneous convexity SAH in the elderly has heretofore been of uncertain origin until several recent case reports have suggested cerebral amyloid angiopathy (CAA) as the etiology. Objective To better appreciate the relationship of convexity SAH in the elderly to CAA. Method The case histories and MR imaging findings of 4 patients with spontaneous convexity SAH were examined. Results T2*-weighted imaging at the time of symptomatic SAH demonstrated features of prior lobar hemorrhage, microbleeds, and/or superficial hemosiderosis fulfilling diagnostic criteria of CAA in all patients. Conclusions CAA may be the foremost cause of convexity SAH in the elderly.
Formation of Transient Intermediates in Low-Temperature Photosensitized Oxidation of an 8-13C-Guanosine Derivative

An 8-13C-labeled guanosine derivative, 2‘,3‘,5‘-O-tert-butyldimethylsilyl-N-tert-butyldimethylsilyl-8-13C-guanosine, was synthesized and its photosensitized oxidation with singlet oxygen carried out below −100 °C. Two transient intermediates that decompose directly to the final major product 5 and CO2 were detected by 13C NMR between −100 and −43 °C. The two intermediates are carbamic acids based on 13C NMR and 2D NMR (HMQC, HMBC) spectra and the formation of final product 5 and of 8-CO2. No endoperoxide intermediate could be detected by low-temperature NMR spectroscopy even at −100 °C. A reaction mechanism is proposed involving initial [4 + 2] cycloaddition of singlet oxygen to the imidazole ring to form an unstable endoperoxide, subsequent rearrangement of the endoperoxide to a dioxirane, and decomposition of the dioxirane to the two observed intermediates. Both oxygen atoms of CO2 are derived from a single oxygen molecule, which strongly supports a dioxirane structure for the precursor of the two obser...
An ambulatory persistence power curve: motor planning affects ambulatory persistence in Parkinson's disease.

Abstract Background/objectives: When performing activity associated with walking, the amount of walking a person does often will depend on their plans. This study was designed to evaluate the relationship between motor planning and ambulatory persistence in participants with Parkinson's disease (PD) and to see if ambulatory persistence was related to the ability to perform activities of daily living (ADL). Methods: 20 individuals with idiopathic PD were recruited to perform the Trail making Test (a test of motor planning) and to wear a step activity monitor for 48 h. The measurement of persistence of an ambulatory event consisted of the number of steps taken during an event and an ambulatory event was defined as continuous ambulation (taking step) without pausing for 3 or more seconds. The resumption of taking step (ambulation) after 3 or more seconds counted as a new ambulatory event. UPDRS-motor and ADL scale were also obtained. Analysis and results: The cumulative percentage of the total ambulatory events at each number of steps was plotted for each subject which when plotted could be described as a sigmoid curve. We found that this sigmoidal curve defined by the equation y = xn/(kn + xn), fit the data well, where k represents a constant specific to each subject, x represents the number of steps during each ambulatory event, and y represents the projected percentage of movement events containing x number of steps or less. (Root Mean Square Error (RMSE) = 0.02, R2 = 0.98). Trail making test part A was highly associated with the constant k (R = −0.74, p
Metal Complexes of 2,3-Quinoxalinedithiol

A series of new planar complexes with the dianion of 2,3-quinoxalinedithiol ligand has been prepared. The complexes have been characterized from the study of their analyses, magnetic moment, conductance, polarograms, electron spin resonance spectra, and electronic spectra, and compared with the available data on the corresponding maleonitriledithiolene and toluene-3,4-dithiolene complexes.
Human Capabilities and Economic Development:The Extreme Outlier Societies

Abstract One of the problems Amartya Sen raised in his capabilities approach was: why do people in some societies realize a much lower level of various kinds of human capabilities than would be expected on the basis of their GDP per capita, while other societies do better than expected? This paper focuses on six capabilities and functionings: life expectancy, schooling, living in a society with less income inequality and less gender inequality, political freedom and life satisfaction. Empirically I start with data on 156 societies and use regression analysis and case diagnostics to identify societies that are extreme outliers. These are identified as Singapore, Saudi Arabia and South Africa, each of which does significantly worse than expected (given their relatively high level of economic development) on two or more of the six capabilities. I then use qualitative analysis to specify, through “process-tracing”, the causal mechanisms that explain why these particular societies are so “unbalanced” in the relationship between their economic development and their human capabilities.
Assessing Driver-Passenger Interactions in a Simulated Driving Environment A pilot study with teen drivers

The combination of teen drivers and peer passengers presents a unique challenge to roadway safety. Teen drivers, being inexperienced, have not mastered essential driving skills and may not know how to safely manage their passengers. Peer passengers may not know how to help the driver and, as a result, become a source of distraction and a risk-promoting factor. We examined the effect of working relationships (i.e. cooperative, individualistic, and competitive) on driver-passenger social interactions in a driving simulator using observational and self-report methods by experimentally inducing the type of working relationship via a pre-drive social interaction task. The preliminary results indicated that dyads assigned to the cooperation condition produced more 'helpful' comments compared to dyads in the competition condition. Initial findings suggest that this type of experimental manipulation may be useful for examining driver-passenger interactions among teens, and those interactions between driver-passenger dyads prior to carry-over into in-vehicle social dynamics. More research is needed to further examine driver-passenger interactions and how differences in these interactions may be associated with safety outcomes. Keywords: Driver distraction; Language: en
The glossy1 Locus of Maize and an Epidermis-Specific cDNA from Kleinia odora Define a Class of Receptor-Like Proteins Required for the Normal Accumulation of Cuticular Waxes

Mutations at the glossy1 (gl1) locus of maize (Zea mays L.) quantitatively and qualitatively affect the deposition of cuticular waxes on the surface of seedling leaves. The gl1 locus has been molecularly cloned by transposon tagging with the Mutator transposon system. The epi23 cDNA was isolated by subtractive hybridization as an epidermis-specific mRNA from Senecio odora (Kleinia odora). The deduced amino acid sequence of the GL1 and EPI23 proteins are very similar to each other and to two other plant proteins in which the sequences were deduced from their respective mRNAs. These are the Arabidopsis CER1 protein, which is involved in cuticular wax deposition on siliques, stems, and leaves of that plant, and the protein coded by the rice expressed sequence tag RICS2751A. All four proteins are predicted to be localized in a membrane via a common NH2-terminal domain, which consists of either five or seven membrane-spanning helices. The COOH-terminal portion of each of these proteins, although less conserved, is predicted to be a water-soluble, globular domain. These sequence similarities indicate that these plant orthologs may belong to a superfamily of membrane-bound receptors that have been extensively characterized from animals, including the HIV co-receptor fusin (also termed CXCR4).
The Fermi Surface of Magnesium III: Local and Nonlocal Pseudopotential Band Structure Models for Magnesium

Extensive de Haas-van Alphen cross-sectional areas and magnetoacoustic calipers for the magnesium Fermi surface were used to generate local- and nonlocal-pseudopotential model Hamiltonians. Both models yielded a good representation of the Fermi surface. Small but significant deviations from experimental data could not be eliminated using the local model, but these were eliminated with the nonlocal model. The values of the local-pseudopotential Fourier coefficients obtained were ${U}_{10\overline{1}0}=+0.014$ Ry, ${U}_{0002}=+0.026$ Ry, ${U}_{10\overline{1}1}=+0.036$ Ry, and ${U}_{10\overline{1}2}=+0.058$ Ry. The variational parameters for the nonlocal pseudopotential were the Fourier coefficients of the self-consistent ion-core potential $V(\mathrm{r})$. The values obtained for these were ${V}_{10\overline{1}0}=\ensuremath{-}0.440$ Ry, ${V}_{0002}=\ensuremath{-}0.412$ Ry, ${V}_{10\overline{1}1}=\ensuremath{-}0.386$ Ry, and ${V}_{10\overline{1}2}=\ensuremath{-}0.299$ Ry.
Smoking and depression in Chinese Americans.

ABSTRACT Background A close link between smoking and depression has been documented by research primarily based on U.S. white populations. This study examined the association between depressive symptoms and smoking behaviors in Chinese American smokers. Methods Analyses were based on baseline data collected from a convenience sample of 199 Chinese smokers who resided in northern California. The sample included 20.6% women, 97 % immigrants, with mean age of 40.8 years and mean cigarettes/day of 8.9. Results Compared with population-based studies of Chinese Americans, the Chinese smokers in the current study reported higher depressive symptoms assessed by the Center for Epidemiologic Studies-Depression Scale [M, 20.4; 95 % confidence interval (CI), 18.8–22.2], higher lifetime prevalence rates of major depressive disorders (30.3 %; 95 % CI, 24.0–37.2 %) and dysthymia (11.6 %; 95 % CI, 7.5–16.9 %). Multiple regression analysis suggested female gender, unemployment, major depression or dysthymia within the past year, previous experience with nicotine withdrawal syndrome, and high temptation to smoke under negative affect situations are associated with a higher level of depressive symptoms. Conclusions The level of depressive symptoms among Chinese American smokers is comparable with that observed in other US populations reported. In the current sample, elevated depressive symptoms were more prominent among women or those who were unemployed, smokers who reported significant nicotine withdrawal at previous quit attempts, and high temptation to smoke when experiencing negative emotions. Findings support further examination of the role of depression in smoking among Chinese Americans and underscore the importance of addressing depressive symptoms when treating tobacco use in Chinese smokers.
Comparison of the efficacy of esmolol and alfentanil to attenuate the hemodynamic responses to emergence and extubation.

Abstract Study Objective : To define the ability of esmolol and alfentanil to control the hemodynamic changes associated with extubation and emergence. Design : Randomized, double-blind, placebo-controlled study. Setting : General surgery operating rooms at a university hospital. Patients : Forty-two ASA physical status I and II patients without history of cardiac or pulmonary disease undergoing surgery not involving the cranium or thorax. Interventions : Patients were given either a bolus dose of normal saline followed by an infusion of normal saline, a bolus dose of alfentanil 5 μg/kg followed by an infusion of normal saline, or a bolus dose of esmolol 500 μg/kg followed by an infusion of esmolol 300 μg/kg/min. Measurements and Main Results : Emergence and extubation resulted in significant increases in heart rate (HR) and blood pressure (BP) in the placebo group. Alfentanil controlled the responses to emergence but prolonged the time to extubation ( p p Conclusions : Emergence and extubation after inhalation general anesthesia result in significant increases in BP and HR in healthy patients. An esmolol bolus dose and subsequent infusion significantly attenuated these responses. A small bolus dose of alfentanil minimized the responses to emergence but prolonged the time to extubation and was no longer protective at that point.
Reversed-phase high-performance liquid chromatography-thermospray mass spectrometry of alprenolol and its ketoxime analogues

Abstract Thermospray mass spectrometric detection is applied for alprenolol and its isomeric ( E and Z ) ketoxime analogues separated by reversed-phase high-performance liquid chromatography. The thermospray process results in high-intensity [M+H] + ion formation. This method of detection provides high level of molecular specificity, and offers advantages for the identification of the stereoisomeric oximes due to the unique fragmentation pattern of the spectra.
Generating Topic Headings During Reading of Screen-Based Text Facilitates Learning of Structural Knowledge and Impairs Learning of Lower-Level Knowledge

This investigation considers the effects of learner-generated headings on memory. Participants (N = 63) completed a computer-based lesson with or without learner-generated text topic headings. Posttests included a cued recall test of factual knowledge and a sorting task measure of structural knowledge. A significant disordinal interaction was observed with the no headings group performing better on the cued recall test and worse on the structural knowledge sorting task. In addition, a measure of structural knowledge using a list-wise rating task was field trialed. The two structural knowledge tasks were analyzed using a Pathfinder network scoring technique that measured both linear and nonlinear text subtopic organization. The sorting and rating tasks were differentially sensitive to participants’ linear and nonlinear knowledge organization. Unexpectedly, the sorting and rating posttest tasks improved cued recall posttest scores. The implications of the results for measuring structural knowledge are considered and suggestions for further studies are presented.
Application of general constitutive principles to the derivation of multidimensional two-phase flow equations

Abstract The process of determining appropriate constitutive equations for multidimensional time averaged two-phase flow equations is studied from the point of view of starting from general principles, and proceeding to specific constitutive equations which contain known physical effects. Energetic effects and phase change are not considered. Models are given for the interfacial momentum transfer, the laminar and turbulent (Reynolds) stresses, and the pressure differences between the phases, and between a given phase pressure and the interfacial average pressure.
The elastic bending energy of pythagorean-hodograph curves

Pythagorean-hodograph (PH) curves admit closed-form expressions for the integral of the square of the curvature with respect to arc length (the ''energy'' integral) involving only rational functions, arctangents, and natural logarithms. In particular, the complex formulation of PH curves greatly facilitates the derivation of these expressions, yielding compact and efficient implementations in any high-level language that provides complex arithmetic. Explicit formulae are presented for the case of Tschirnhausen's cubic and the regular PH quintics, and in the latter case the use of the energy integral in optimizing the ''fairness'' of geometric Hermite interpolants is discussed. Compelling empirical evidence indicates that, for ''reasonable'' derivative data, first-order PH quintic Hermite interpolants are systematically of lower energy than their ordinary cubic counterparts.
Bending of Anisotropic Sandwich Beams with Variable Thickness

In the stress analysis of anisotropic sandwich construction, a theory based on the assumption of constant thickness has been available for some time. With the design of high-performance spacecraft,...
EUS-guided fiducial placement after radical prostatectomy before targeted radiation therapy for prostate cancer recurrence

p fi r g t a n r r t u w o e d Intensity-modulated radiotherapy (IMRT) is a modality of image-guided radiation therapy that allows the delivery of high treatment doses while minimizing the effects on adjacent organs. IMRT is well-tolerated, with similar or less toxicity than 3-dimensional conformal radiotherapy. IMRT, however, requires the placement of fiducial markers to guide treatment delivery. Fiducials are particularly important in patients after radical prostatectomy because of the lack of a definitive target. Challenges also exist in clearly delineating the prostate bed because of postsurgical anatomical changes, such as shortening of the urethra. EUS-guided placement of gold fiducial markers before targeted radiation therapy is a novel clinical application of therapeutic linear EUS. Yang et al recently reported on 16 patients with newly diagnosed prostate cancer who underwent EUS placement of fiducials into the prostate gland before IMRT. Herein, we discuss a new application of linear EUS in patients with tumor recurrence after radical prostatectomy. Fiducials were placed into the prostate fossa in 6 postprostatectomy patients before salvage IMRT.
“It was like a little community”: An ethnographic study of online learning and its implications for MOOCs

In this time of social, technical, educational and industrial upheaval, time and space are being compressed and stretched as social actors develop new practices in response to shifts in their lived experience. In the American educational sector, these phenomena have crystalized in the meteoritic rise of MOOCs, massive open online courses. The story of their ascent weaves together neoliberal shifts in financing education, technology developments, and perceived business opportunities. MOOCs have captured the imagination of the business press, venture capitalists, and university leaders. However, surprisingly little attention has been paid to the perceptions of students who are taking online courses – in other words, the users. Drawing on an ethnographic study of a small online class, this paper describes the limitations of MOOC pedagogies by comparison with low-enrollment online courses, and concludes by casting doubt on the effectiveness of MOOC learning experiences as well as MOOC business models.
Coronal Temperature Measurements Near a Helmet Structure Base at the 1973 Solar Eclipse

Observations of coronal Fe XIV emission lines from the NE quadrant during the 1973 solar eclipse are reported. Temperatures are deduced from a pure thermal broadening model, and, in the region near an observed white-light enhancement, an alternative interpretation of halfwidth as being in part due to turbulent velocities is suggested.
An infrared spectroscopic study of NH4Br —ammonium bromide to 55 GPa

Abstract We have measured the infrared spectrum of NH4Br—ammonium bromide to 55 GPa at 300 K. The hydrogen bond in this system is initially nearly linear, and the magnitude of volumetric compression over this pressure range is between 45% and 55%: thus, dramatic compression of the N – H … Br distances is expected. However, we observe pressure shifts of the internal modes of the ammonium ion that are small, non-linear and change in sign under compression. For example, the ν 3 -asymmetric stretching band of the NH4 group near 3145 cm−1 undergoes an initial decrease with pressure to ∼5 GPa, followed by near-constancy to 20 GPa, and increases in frequency at higher pressures: it has essentially an identical frequency at 30 GPa as it does at 2.5 GPa. The pressure dependences of the internal modes indicate that if strong hydrogen bonding is present in the system, or is induced by pressure, then there must be competing and compensating effects that produce near-constancy or pressure-induced increases of the internal ammonium ion stretching frequencies as well as decreases in the internal bending frequencies. Our results indicate that three effects likely prohibit the pressure-induced onset of strong hydrogen bonding within the system: (1) a change in the N – H … Br bond angle at high pressures, (2) overbonding on the bromine ion by the surrounding hydrogen atoms, and (3) inter-ammonium ion hydrogen–hydrogen repulsion which is enhanced with increasing pressure and decreasing volume. Systematics of the pressure dependences of the N–H stretching frequencies of the ammonium halides indicate that the last effect, H–H repulsion, dominates in these systems. Thus, it is the abundance of hydrogen within the NH4Br lattice that produces the primary effect on the pressure shift of the N–H stretching vibrations, rather than increased hydrogen bonding.
Mutant frequency and mutational spectra in the Tk and Hprt genes of N‐ethyl‐N‐nitrosourea‐treated mouse lymphoma cells†

The mouse lymphoma assay (MLA) utilizing the Tk gene is widely used to identify chemical mutagens. The autosomal location of the Tk gene allows for the detection of a wide range of mutational events, from point mutations to chromosome alterations. However, chemically induced point mutation spectra in the Tk gene of mouse lymphoma cells have not been characterized. In this study, we determined and compared the mutagenicity and mutational spectra of N-ethyl-N-nitrosourea (ENU) in the Tk and Hprt genes of mouse lymphoma cells. Treatment of L5178Y mouse lymphoma cells with 100 μg/ml ENU induced a Tk mutant frequency of 756 × 10−6 and an Hprt mutant frequency of 311 × 10−6. Sequence analysis of Tk and Hprt mutant cDNAs showed a similar overall mutation pattern in the two genes with base-pair substitutions accounting for 83% of non–loss of heterozygosity mutations in the Tk gene and 75% of all mutations in the Hprt gene. The most common point mutation induced by ENU was G:C A:T transition (36 and 28% of independent mutations detected in the Tk and Hprt genes, respectively). The mutation spectra induced by ENU in both the Tk and Hprt genes were different from the respective patterns produced in mutants from untreated cells. About 9% of Tk and 7% of Hprt mutations from control cells were in-frame deletions, whereas no such mutations were found among the ENU-induced Tk and Hprt mutations. Our results indicate that ENU produces a chemical-specific point mutational profile in the Tk gene of mouse lymphoma cells that is remarkably similar to that found in the X-linked Hprt gene. This study provides evidence that the MLA can be used not only to detect point mutagens but also for analysis of mutational spectra. Environ. Mol. Mutagen. 39:296–305, 2002. Published 2002 Wiley-Liss, Inc.
Distribution of polycyclic aromatic hydrocarbons in oyster (Crassostrea virginica) and surface sediment from two estuaries in South Carolina

The concentration of polycyclic aromatic hydrocarbons (PAHs) was determined in oysters and sediments collected from two high salinity estuaries from the coast of South Carolina. The two estuaries were Murrells Inlet (urban), an estuary receiving urbanized drainage and run-off, and North Inlet (non-urban), receiving drainage from heavily forested terrarin and minimal anthropogenic input. A minimum of thirty (30 stations were sampled in Murrells and North Inlets, respectively. A composite oyster sample (n=30) was analyzed for each station. For sediment, a sample from the top 3–5 cm of the sediment surface from each station was analyzed. In oyster from Murrells Inlet, total PAHs concentrations within the 75 percentile were located in the northern portion of the estuary near marinas, adjacent to residential areas of high population density, near commercial enterprises or run-off from storm drains. Total PAHs within the 25 percentile were located near the mouth of the estuary. These results showed a PAHs concentration gradient in the estuary that was highest in narrow creeks, where the urban shore interfaced with tidal creeks and lowest at the mouth of the estuary. In the case for sediment, a similar gradient was observed. In comparing the mean total PAHs of the two inlets, Murrells Inlet had significantly higher (p<0.01) total PAHs concentrations than North Inlet for oyster and sediment, respectively.
COMPLEX AMPLITUDES FOR ELECTRON SCATTERING BY ATOMS

Abstract : The partial waves scattering theory was applied to electron scattering by U and f atoms at 40 and 11 kev. The complex atomic scattering amplitudes were computed and applied to the scattering by the UF6 molecule. The predicted electron scattering by the UF6 molecule was in accord with experiment.
PUBLIC GOODS AND OPEN ACCESS

Many proposals have been considered to reform scholarly communications. Some are mild adaptations of the existing systems; others are radical revisions insofar as the economic model is concerned. This article will examine these proposals and focus on the substantial, enduring reason to modify scholarly communication in a minor manner in order to accommodate the public goods nature of many scholarly articles.
Employment location choices: Factors associated with the likelihood of homebased employment

The purpose of this research analysis is to investigate the factors that are associated with the likelihood of a worker choosing homebased employment. Using a sample of 6,744 employed men and women from the 1984 Panel Study of Income Dynamics, a logit estimation procedure is employed. Factors which decrease the likelihood of being a homebased worker include minority status, higher levels of total family labor income, a high school education or less, and longer working hours. Older workers, workers without children, workers with young children under age six, the self-employed, and farmers are all more likely to be involved in homebased employment.
Is Hilbert space too large

Two aspects of the irreversible measurement transformation are explored. The first is the range of allowed values for the joint uncertainty of two operators having no common eigenvector. The second is the constraint on states and operations following from the requirement that the uncertainty resolved by completing a measurement shall be always finite.
Evidence for a functional ATP-citrate lyase:NADP-malate dehydrogenase pathway in bovine adipose tissue: enzyme and metabolite levels.

Abstract Activities of key lipogenic and glycolytic enzymes were determined in extracts of crude homogenates to elucidate the rate-limiting step(s) for lipogenesis from lactate and glucose in bovine subcutaneous adipose tissue. The enzymes ATP-citrate lyase, NADP-malate dehydrogenase, and pyruvate carboxylase were shown to have enough activity to account for the rates of in vitro lipogenesis from 10 m m lactate with or without 2 m m glucose. Glucose utilization for fatty acid synthesis appears to be limited by the low activities of key glycolytic enzymes, especially hexokinase. Attempts were also made to estimate enzyme activities in bovine subcutaneous adipose tissue being incubated in vitro by relating primary substrate levels to kinetic characteristics for the enzymes. ATP-citrate lyase was estimated to be operating at levels equivalent to the rates of lactate incorporation into fatty acids in the absence or presence of 2 m m glucose in the incubation media. Additionally, metabolite levels were measured in rapidly frozen samples of bovine subcutaneous adipose tissue to estimate the relative importance of key lipogenic enzymes in vivo . At the citrate and malate levels measured in vivo , ATP-citrate lyase would be operating at levels that approximate those estimated in vitro .
A detailed mechanism for the gas-phase atmospheric reactions of organic compounds

Abstract A gas-phase reaction mechanism for the atmospheric photooxidations of over 100 alkanes, alkenes, aromatic hydrocarbons, alcohols, ethers and other compounds representative of the range of reactive organics emitted into polluted atmospheres is described. Most of these organic species are represented using generalized reactions with variable rate constants and product yield coefficients for which individual assignments were made or estimated. This mechanism employs 19 species to repsent the reactive oxygenated and organic nitrate products, and includes the gas-phase reactions of SO2, but does not include heterogeneous or liquid-phase reactions. The evaluation of this mechanisms, by comparison of its predictions against the results over 500 environmental chamber experiments, described in a separate paper. This detailed mechanism can be used in assessments of relative atmospheric reactivities of organic compounds, and can provide the basis for the derivation of more condensed mechanisms for use in air quality simulation models.
Wnt/β-catenin signaling has an essential role in the initiation of limb regeneration

Anuran (frog) tadpoles and urodeles (newts and salamanders) are the only vertebrates capable of fully regenerating amputated limbs. During the early stages of regeneration these amphibians form a "blastema", a group of mesenchymal progenitor cells that specifically directs the regrowth of the limb. We report that wnt-3a is expressed in the apical epithelium of regenerating Xenopus laevis limb buds, at the appropriate time and place to play a role during blastema formation. To test whether Wnt/beta-catenin signaling is required for limb regeneration, we created transgenic X. laevis tadpoles that express Dickkopf-1 (Dkk1), a specific inhibitor of Wnt/beta-catenin signaling, under the control of a heat-shock promoter. Heat-shock immediately before limb amputation or during early blastema formation blocked limb regeneration but did not affect the development of contralateral, un-amputated limb buds. When the transgenic tadpoles were heat-shocked following the formation of a blastema, however, they retained the ability to regenerate partial hindlimb structures. Furthermore, heat-shock induced Dkk1 blocked fgf-8 but not fgf-10 expression in the blastema. We conclude that Wnt/beta-catenin signaling has an essential role during the early stages of limb regeneration, but is not absolutely required after blastema formation.
Mg/Ca–temperature proxy in benthic foraminifera: New calibrations from the Florida Straits and a hypothesis regarding Mg/Li

[1] Over the past decade, the ratio of Mg to Ca in foraminiferal tests has emerged as a valuable paleotemperature proxy. However, large uncertainties remain in the relationships between benthic foraminiferal Mg/Ca and temperature. Mg/Ca was measured in benthic foraminifera from 31 high-quality multicore tops collected in the Florida Straits, spanning a temperature range of 5.8° to 18.6°C. New calibrations are presented for Uvigerina peregrina, Planulina ariminensis, Planulina foveolata, and Hoeglundina elegans. The Mg/Ca values and temperature sensitivities vary among species, but all species exhibit a positive correlation that decreases in slope at higher temperatures. The decrease in the sensitivity of Mg/Ca to temperature may potentially be explained by Mg/Ca suppression at high carbonate ion concentrations. It is suggested that a carbonate ion influence on Mg/Ca may be adjusted for by dividing Mg/Ca by Li/Ca. The Mg/Li ratio displays stronger correlations to temperature, with up to 90% of variance explained, than Mg/Ca alone. These new calibrations are tested on several Last Glacial Maximum (LGM) samples from the Florida Straits. LGM temperatures reconstructed from Mg/Ca and Mg/Li are generally more scattered than core top measurements and may be contaminated by high-Mg overgrowths. The potential for Mg/Ca and Mg/Li as temperature proxies warrants further testing.
Thermal expansion of anatase and rutile between 300 and 575 K using synchrotron powder X-ray diffraction

High-precision unit-cell parameters for the TiO2 polymorphs anatase and rutile at temperatures between 300 and 575 K have been determined using Rietveld analysis of synchrotron powder XRD data. Polynomial models were used to express the tetragonal unit-cell parameters as a function of absolute temperature, with a (anatase)=1.759 37x10-8xT2+6.418 16x10-6xT+3.779 84, c (anatase)=6.6545x10-8xT2+4.0464x10-5xT+9.4910, V (anatase)=2.237 58x10-6xT2+1.027 77x10-3xT+135.602, a (rutile)=-6.636 42x10-11xT3+1.005 01x10-7xT2-1.009 9310-5xT+4.586 34, c (rutile)=-4.115 50x10-11xT3+6.405 94x10-8xT2+4.675 61x10-7T+2.951 81, and V (rutile)=-2.7790x10-9xT3+4.2386x10-6xT2-3.3551x10-4xT+62.100. The polynomial expressions were used to calculate linear (alpha) and volume (beta) thermal expansion coefficients of anatase and rutile between 300 and 575 K. At 298.15 K, these values were alphaa=4.46943x10-6 K-1, alphac=8.4283x10-6 K-1, and beta=17.3542x10-6 K-1 for anatase, and alphaa=6.99953x10-6 K-1, alphac=9.36625x10-6 K-1, and beta=28.680x10-6 K-1 for rutile.
Systems with low distributed simulation overhead

Distributed simulation often involves a large number of overhead messages. This may lead to severe performance degradation of the simulator as pointed out in several previous works. In this work special classes of systems which can be simulated with low overhead-in most systems identified here the total number of overhead messages on any given communication line is at most one, irrespective of the time up to which the physical system is to be simulated-are presented. This includes acyclic systems, some closed queuing networks, some open cyclic queuing networks, and other special types of cyclic networks. Distributed simulation algorithms specially tailored to these systems are given. By isolating these classes of systems and designing distributed simulation algorithms specifically geared for them, a large number of overhead messages can be avoided. By contrast, other distributed simulation algorithms are usually designed for more general systems and they usually require too many overhead messages, even in simulating these special classes of systems. >
Measuring Oncogenic Signaling Pathways in Cancer with PET: An Emerging Paradigm from Studies in Castration-Resistant Prostate Cancer

As parallel advances in cancer biology and drug development continue to elevate the role of targeted therapies in oncology, the need for imaging biomarkers that systematically measure the biology associated with therapeutic intervention has become more urgent. Although the molecular imaging community has a commitment to develop technologies to this end, few investigational radiotracers directly measure the biology of common oncogenic signaling pathways often addressed by targeted therapies. Visible progress has been achieved with a handful of radiotracers rationally designed to intercalate the pathobiology of prostate cancer, a molecularly heterogeneous disease nevertheless broadly defined by a fairly small repertoire of recurrent oncogenic lesions. Significance: That variable treatment responses or emergent resistance phenotypes are often documented in humans argues strongly for diagnostic technologies that can be realistically applied posttherapy to capture the dynamic patterns of disease response. The purpose of this review is to describe a collection of radiotracers developed to measure the pathobiology of prostate cancer for improved treatment monitoring, placing particular emphasis on the biologic rationale for their preparation. A chronologic description of radiotracer development programs is outlined, primarily to stress how an ongoing dialectic between earlier and more contemporary imaging technologies has accelerated discovery. Cancer Discov; 2(11); 985–94. ©2012 AACR.
Characteristics of spontaneous miniature and subminiature end‐plate currents at the mouse neuromuscular junction.

1. Neuromuscular junctions of the mouse diaphragm were voltage clamped with a two-electrode voltage clamp in order to evaluate time characteristics of miniature end-plate currents (MEPCs). 2. The MEPCs fell into two amplitude classes: a larger class with an overall bell-shaped distribution (bell MEPCs) and a smaller class which forms a right-hand skew distribution (skew MEPCs). The mean MEPC amplitudes varied greatly because of the large range in the ratio of skew to bell MEPCs. This variation was greatest in neonate mice. 3. Rise time and time-to-peak were the same for MEPCs of the skew and bell classes. The MEPCs of both classes in neonate and adult mice had the same ratio of area (charge) over amplitude and the same time constant of decay. The absolute values changed with maturation (at 30 degrees C the ratio of area/amplitude was 4.5 +/- 0.8 ms in the newborn and 1.2 +/- 0.05 ms in the adult; the time constant of decay was 5.6 +/- 1.2 ms in the newborn and 0.8 +/- 0.05 ms in the adult). 4. Atypical MEPCs were found at all junctions. These had slow rising and falling phases, notches on the rising phases or a step the size of the sub-MEPC class. The number of atypical MEPCs increased during the experiment. 5. The data suggest that both skew and bell MEPC classes are released from the same presynaptic region and are generated by the same postsynaptic mechanism.
Echogenic lipsomes for targeted drug delivery

Echogenic immunoliposomes (ELIP) are under development to enable ultrasound-controlled drug delivery. Mechanistic studies in vitro have revealed that stable cavitation is correlated with enhanced recombinant tissue Plasminogen Activator (rt-PA) thrombolysis, yet strategies to optimize the occurrence of such bubble activity and avoid potential harmful bioeffects have yet to be identified. Stable cavitation is characterized by bubbles pulsating gently in response to the time-varying acoustic pressure in an ultrasound field. A review of in vitro sonothrombolysis studies utilizing a commercial US contrast agent or echogenic liposomes loaded with rt-PA to nucleate stable cavitation will be presented. Strategies for the development of ultrasound-enhanced thrombolysis and drug delivery will be discussed. This work was supported by NIH 1RO1 NS047603.
Adjuvant radiotherapy for atypical and malignant meningiomas: a systematic review

Atypical meningiomas (AMs) and malignant meningiomas (MMs) are tumors with a lower incidence and poorer prognosis than benign meningiomas. The role of radiotherapy as an adjuvant to surgical resection, especially for AMs, is incompletely defined. In this study, the English-language literature was systematically reviewed for studies that reported tumor characteristics, treatment parameters, and clinical outcomes after adjuvant radiotherapy for AM and MM, including overall survival, progression-free survival, and/or time to recurrence or mortality. Clinical outcomes were further assessed in the context of resection status, timing of administration, and radiation dose. Outcomes after stereotactic radiosurgery were also examined. Treatment toxicity and other potential prognostic or confounding factors were appraised. Ten and 11 studies for AM and MM, respectively, met the inclusion criteria. The median 5-year progression-free survival and overall survival after adjuvant radiotherapy were 54.2% and 67.5%, respectively, for AM and 48% and 55.6% for MM. The complication rates were 11.1% for AM and 5.1% for MM. Incomplete resection and radiation dose <50 Gy conferred significantly poorer 5-year progression-free survival. Most studies were unable to demonstrate a statistically significant prognostic benefit for adjuvant radiotherapy in AM. In conclusion, adjuvant radiotherapy significantly improved local control of AMs and MMs, especially after subtotal resection. Study limitations, including inadequate statistical power, may underlie the studies' inability to demonstrate a statistically significant benefit for adjuvant radiotherapy in AM. Because these tumors preferentially recur within 5 years of surgical resection, future studies should define whether early adjuvant therapy should become part of the standard treatment paradigm for completely excised tumors.