cssi/SciSciGPT-SciSciNet huggingface dataset:
Adsorption of catechol and comparative solutes on hydroxyapatite.

Contemporary medical and dental adhesives often have difficulty sticking to wet surfaces or weaken with long-term exposure to water. Substantial research has been dedicated to finding a means of achieving adhesion in an aqueous environment. A study evaluates the adsorption of catechol relative to other chemical groups as means of gauging how effective they may be as adsorptive groups in adhesives. Contact angle and surface-tension measurements of solutions of catechols and other chemical groups were used to determine their works of adhesion. Adsorption isotherms were also constructed to ascertain Langmuir constants. Solutes containing catechol groups were compared to solutes containing other polar groups to see how well catechol adsorbs to hydroxyapatite, the mineral component of bones and teeth, relative to other chemical groups found in adhesives. The results of this study show that catechol and molecules containing catechol groups have higher rates and energies of adsorption to hydroxyapatite than do groups such as alcohols, amines, and carboxylic acids.
Leisure-time physical activity in school environments: an observational study using SOPLAY.

Background. Schools provide settings for physical activity (PA), but objective tools for measuring PA are lacking. We assessed an instrument to directly observe group PA and measured the leisure-time PA of adolescents throughout the school day. Methods. Leisure-time PA was studied by direct observation in 24 middle schools in Southern California using SOPLAY (System for Observing Play and Leisure Activity in Youth). SOPLAY uses momentary time sampling to record the activity of each individual as sedentary, walking, or very active. Results. The largest proportion of students visited activity areas at lunch time (19.5%), followed by before (4.1%) and after school (2.1%). More boys than girls visited activity areas before school (33.4 vs 7.7) and at lunch time (148.8 vs 36.7). Boys in areas engaged in more moderate to vigorous PA than girls before school (59.6 vs 40%) and at lunch time (67.7 vs 51.7%). Conclusions. Few students use opportunities to be physically active during lesiure time at school. Policies and environmental manipulations (e.g., supervision, equipment, structured programs) are needed to attract more adolescents, especially girls, to existing activity areas. The feasibility of SOPLAY for measuring group PA was established.
HOMOGENEOUS CHEMICAL VAPOR DEPOSITION OF AMORPHOUS SEMICONDUCTOR THIN FILMS

Abstract In this paper we discuss the properties of amorphous hydrogenated silicon and germanium films prepared by homogeneous chemical vapor deposition. Emphasis is placed upon the important differences between HOMOCVD and plasma-deposited films. Experiments and calculations are presented which illustrate the most important reactor dynamical parameters.
Structure and Variability of the Florida Current at 27°N: April 1982–July 1984

Abstract Results of a two-year field experiment as part of the SubTropical Atlantic Climate Studies (STACS) program in the Straits of Florida are presented. Temperature and absolute ocean current observations were obtained by PEGASUS acoustic current profilers over 16 cruises during which repeated cross sections of the Florida Current were made at 27°N. Results are shown for the mean velocity and temperature fields, the perturbation horizontal kinetic energy and potential energy fields and for those energy conversion terms that could be computed directly from the data. The barotropic and baroclinic energy conversion terms, although small, indicate that the flow is stable for both types of perturbations. A 1arge part of the variability is contributed by short time scales (one week or less). The average and standard deviation of northward volume transport by the Florida Current during these cruises was (31.7 ± 3.0) × 106 m3 s−1. Barotropic and baroclinic contributions to the total heat flux across the North...
Vibration Control in a Flexible Beam Using a Conservative Force

The use of end forces for vibration control in structural elements is considered in this paper. The control process involves direct vibration measurement and observer-based estimation of vibration modal amplitudes, which are used to determine when to apply (or increase) an end load such that it will remove vibration energy from the structure. For this study we consider the transverse vibrations of a cantilever beam with a buckling type of end load that can be switched between two values, both of which are below the buckling threshold. The stability of the control system is proven using a Lyapunov analysis, and its effectiveness is demonstrated using simulations and physical experiments. It is shown that the effectiveness of the approach is affected by the bandwidth of the actuator and the attendant characteristics of the filter, the level of the control force, and the level of the end force when it is not actuated. The experiments employ a beam fitted with a cable mechanism and motor for applying the end force, and a piezoelectric patch for taking vibration measurements. It is shown that the first two beam modes, that is, those within the bandwidth limitation of the motor, are very effectively controlled by the proposed scheme.Copyright © 2004 by ASME
Method For Evaluating The Display Of Images

In this paper a two-dimensional measure of image quality is proposed and discussed. The measure can be used as an objective specification for imaging systems, can be readily related to several forms of subjective data, and is based on easily-understood definitions. The paper includes a brief summary of the concepts, with examples; and a discussion of some critical details.© (1979) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Isotopic carbon analysis using low energy protons

An investigation of the /sup 12/C(p, gamma )/sup 13/N and /sup 13/C(p, gamma )/sup 1 4/N reactions has been made to determine their applicability for assaying materials for their /sup 13/C enrichment. The system was calibrated by measuring the ratio of the yield from the /sup 12/C(p, gamma )/sup 13/N reaction to the yield from the /sup 13/C(p, gamma )/sup 14/N reaction as a function of the /sup 13/C enrichment for petasaium acetate targets having known /sup 13/C enrichments. Using the experimentally determined calibration curve, many different materials have been assayed. Measurements were made using both a high resolution Ge(Li) detector and a NaI detector. Several proton beam energies were used to determine the optimum energy for assay measurements. The radiative eapture technique for determining /sup 13/C enrichment is compared with the more classical techniques for the analysis of /sup 13/C tracer experiments.
Cooperative Self-Assembly of Dendrimers via Pseudorotaxane Formation from a Homotritopic Guest Molecule and Complementary Monotopic Host Dendrons

Interaction of the homotritopic guest 1,3,5-tris[p-(benzylammoniomethyl)phenyl]benzene tris(hexafluorophosphate) (1a) with dibenzo-24-crown-8 (DB24C8) leads to the sequential self-assembly of [2]-,...
Nonparametric regression estimation under mixing conditions

Abstract For j=1, 2,…, let {Zj}={(Xj, Yj)} be a strictly stationary sequence of random variables, where the X's and the Y's are R p-valued and R q-valued, respectively, for some integers p, q⩾1. Let φ be an integrable Borel real-valued function defined on R q and set r(x)= E [φ(Y)∣X=x], x ϵ R p . The function φ need not be bounded. The quantity r(x) is estimated by r n (x)= R n (x) f n (x) , where fn(x) is a kernel estimate for the probability density function f of the X's and R n (x)=(nh p ) -1 Σ n j=1 φ(Y j ) · K( (x−X j ) h ) . If the sequence {Zj} enjoys any one of the standard four kinds of mixing properties, then, under suitable additional assumptions, rn(x) is strongly consistent, uniformly over compacts. Rates of convergence are also specified.
Learning scientific reasoning with the interactive computer

In this paper I report on a set of ten programs, the Scientific Reasoning Series. These programs take an area difficult to deal with in conventional science courses, the nature of scientific reasoning, and make it accessible to a much wider group of students. The aim of this material is to make improvements in scientific reasoning for all students over about 10 years old. The programs are highly interactive, adapting to the needs of the individual user. They are also motivationally strong, because of formative evaluation within public library environments. About 20 hours of student material is available. We argue that this material has important suggestions for the future of science education.
High Incidences of Transmissible Kidney Tumors in Uminoculated Frogs Maintained in a Laboratory.

Various workers have shown that the Lucke carcinoma, a transmissible kidney tumor of the leopard frog, occurs spontaneously at low incidence (6.7 percent maximum). However, we have consistently observed much higher incidences (50 percent maximum), a finding of probable significance in the epidemiology and natural transmission of the tumor. Age, metabolic level, and cross infection are being investigated as possible factors in determining the tumor incidence.
Joint Detection and Decoding for MIMO Systems Using Convolutional Codes: Algorithm and VLSI Architecture

In this paper, we present a novel approach to perform joint detection and decoding for spatial multiplexing multiple-input multiple-output (MIMO) systems which utilize convolutional codes. The bit error rate (BER) performance of the proposed approach is significantly better than that of systems which utilize separate detection and decoding blocks. Formal algorithms with two possible system setups are presented and their performance documented. In particular, for a reference 4 × 4, 16-QAM system using a rate 1/2 convolutional code with generator polynomial [247, 371] and a constraint length of 8, improvements in signal-to-noise ratio (SNR) of 2.5 dB and 3 dB are achieved over conventional soft decoding at a BER of 10-5. The proof of concept VLSI architecture for one algorithm is provided and a novel way to reduce memory usage is demonstrated. Results indicate that better performance over conventional systems is achievable with comparable hardware complexity. The proposed design was synthesized and layout with 65-nm CMOS technology at 181-MHz clock frequency. An average throughput of 216.9 Mbps at a SNR of 13 dB with area equivalent to 553 Kgates was achieved.
Nicotinic Agonist Binding Site Mapped by Methionine- and Tyrosine-Scanning Coupled with Azidochloropyridinyl Photoaffinity Labeling

Agonists activating nicotinic acetylcholine receptors (nAChR) include potential therapeutic agents and also toxicants such as epibatidine and neonicotinoid insecticides with a chloropyridinyl substituent. Nicotinic agonist interactions with mollusk (Aplysia californica) acetylcholine binding protein, a soluble surrogate of the nAChR extracellular domain, are precisely defined by scanning with 17 methionine and tyrosine mutants within the binding site by photoaffinity labeling with 5-azido-6-chloropyridin-3-yl probes that have similar affinities to their nonazido counterparts. Methionine and tyrosine are the only residues found derivatized, and their reactivity exquisitely depends on the direction of the azido moiety and its apposition to the reactive amino acid side chains.
Tonal fusion of consonant musical intervals: the oomph in Stumpf.

Three experiments investigated Stumpfs fusion principle of tonal consonance. In Experiment 1, subjects listened to single tones or to tone pairs that represented 12 musical intervals and indicated whether they thought one or two tones had sounded. The fusion principle would be supported by an increase in reaction times or errors in response to conventionally consonant intervals as opposed to dissonant ones. A significant main effect of interval size was found in the error data of Experiment 1, with the most errors produced by intervals of an octave (12 semitones). Experiment 2 compared a smaller set of intervals in distinguishing two- from three-tone combinations. A significant main effect of interval size was found in both the response time and error data in a direction consistent with the fusion principle. Experiment 3 investigated an explanation of the fusion principle based on the harmonic series. In three-tone combinations, more fusion of the higher pair of tones was observed when the lower pair formed an octave or perfect fifth than when the lower pair formed a tritone. Fusion may represent a tendency for people to interpret pitch combinations that could represent harmonics resulting from a single fundamental as timbres rather than as chords.
Calcium-induced actin depolymerization reduces NMDA channel activity

Actin filaments are highly concentrated in postsynaptic densities at central excitatory synapses, but their influence on postsynaptic glutamate receptors is unknown. We tested whether actin depolymerization influences NMDA channel activity in whole-cell recording on cultured hippocampal neurons. The ATP- and calcium-dependent rundown of NMDA channels was prevented when actin depolymerization was blocked by phalloidin. Rundown of AMPA/kainate receptors was unaffected by phalloidin. Cytochalasins, which enhance actin-ATP hydrolysis, induced NMDA channel rundown, whereas taxol or colchicine, which stabilize or disrupt microtubule assembly, had no effect. Protease inhibitors also had no effect. Our results suggest that calcium and ATP can influence NMDA channel activity by altering the state of actin polymerization and are consistent with a proposed model in which actin filaments compartmentalize a channel regulatory protein.
Cytochalasin Modulation of Nicotinic Cholinergic Receptor Expression and Muscarinic Receptor Function in Human TE671/RD Cells: A Possible Functional Role of the Cytoskeleton

Previous studies have shown that cells of the TE671/RD human clonal line express muscle-type nicotinic acetylcholine receptors (nAChR) and m3-type muscarinic acetylcholine receptors (mAChR) whose numbers and function are regulated by agonist treatment and second messenger modulation. Here we show that cytochalasin treatment, which causes disruption of actin networks, induces marked changes in the numbers and distribution of nAChR, but not mAChR. Moreover, whereas cytochalasin treatment fails to alter nAChR function significantly, it acutely potentiates mAChR-mediated phosphoinositide hydrolysis. Treatment of TE671/RD cells with different cytochalasin analogues (rank order efficacy at 5 micrograms/ml is H > J = B = C = D > A = E) produces a two- to fourfold increase in numbers of membrane-bound nAChR (Bmax in units of specific 125I-labeled alpha-bungarotoxin binding per milligram of membrane protein). nAChR up-regulation is evident after 1-2 days of cytochalasin B exposure, is maximal after 3-6 days of drug treatment, and is dominated by an approximately 10-fold increase (per cell) in an intracellular nAChR pool. Cytochalasin-induced nAChR up-regulation is similar in magnitude to, but not additive with, up-regulation of nAChR following chronic exposure to nicotine or phorbol ester. Northern blot analysis shows a four- to five-fold coordinate increase in levels of mRNA that encode nAChR alpha, beta, gamma, or delta subunits in cytochalasin-treated cells, suggesting that nAChR up-regulation has a possible transcriptional basis. Studies done using a 86Rb+ efflux assay indicate that cytochalasin treatment has no significant effect on nAChR function. By contrast, cytochalasin treatment has no effect on the numbers of mAChR as assessed by binding studies with the radioantagonist 3H-labeled quinuclidinyl benzilate, but it induces marked enhancement of carbachol-stimulated, but not basal, phosphoinositide hydrolysis. These studies suggest that presumed modulation by cytochalasin treatment of cytoskeletal microfilament integrity can differentially influence expression and function of mAChR (a prototype of the metabotropic receptor superfamily) and nAChR (a prototype of the ligand-gated ion-channel superfamily). The results also suggest possible new roles for the cytoskeleton in regulation of membrane receptor expression, function, and cross talk.
Interaction of HNO3 with water‐ice surfaces at temperatures of the free troposphere

The uptake of gas-phase HNO3 by water-ice films has been measured in a low-temperature, coated-wall flow tube under conditions where water-ice, and not a hydrate of nitric acid, is thermodynamically stable. It is observed that there is uptake of HNO3 on the order of 1 → 3 ×1014 molecules per cm² of ice film on a short timescale, and a somewhat smaller uptake on a much longer timescale of 10's of minutes. The short timescale uptake is insensitive to the nitric acid partial pressure, varying by not more than a factor of two over a 20-fold variation in the partial pressure of HNO3 from 1.3 × 10−7 to 3.1 × 10−6 torr. This implies that the ice surface is saturated with HNO3 at these partial pressures. Also, the uptake is somewhat dependent on temperature over the range 208 to 248 K, with the largest uptake at the lowest temperatures. The uptake is largely irreversible, with only 20 → 25% of the adsorbed HNO3 desorbing from the film when the exposure to gas-phase HNO3 is stopped. These experiments suggest that adsorption to cirrus cloud surfaces may be an important scavenging process of HNO3 in the troposphere.
Association genetics of carbon isotope discrimination, height and foliar nitrogen in a natural population of Pinus taeda L.

Loblolly pine, Pinus taeda L., is one of the most widely planted, commercially and ecologically important tree species in North America. We took an association genetics approach, using an unimproved population of 380 clonally replicated unrelated trees, to test 3938 single nucleotide polymorphisms (SNPs) in as many genes for association with phenotypic variation in carbon isotope discrimination, foliar nitrogen concentration and total tree height after two growing seasons. Best linear unbiased prediction (BLUP) was used with a spatial adjustment to remove environmental variation from phenotypic data derived from a common garden experiment. After correction for multiple testing, a total of 14 SNPs were associated with the traits of carbon isotope discrimination (n=7), height (n=1) and foliar nitrogen concentration (n=6) using 380 clones. Tails of the population phenotypic distribution were compared for allele frequency differences, revealing 10 SNPs with allele frequency in at least one tail significantly different from the overall population. Eight associated SNPs were in sequences similar to known genes, such as an AP2 transcription factor related to carbon isotope discrimination and glutamate decarboxylase associated with foliar nitrogen concentration, and others were from unknown genes without homologs in Arabidopsis.
Effects of Violating Local Independence on IRT Parameter Estimation for the Binomial Trials Model

Abstract The appropriateness of the Binomial Trials Model for test data that consist of multiple attempts of the same item needs to be determined because the presence of learning or fatigue effects may violate the model's assumption of local independence. The purpose of this study was to determine what effect the severity of the violation of local independence (VLI), coupled with different sample size (SS), test length (TL), and test difficulty (TD) had on the estimation of the model difficulty parameter, b, using computer simulation techniques. Each of the following conditions was replicated 100 times under a completely crossed design: SS (100, 200, 500, 2,000); TL (5, 10, 20, 25 attempts); TD (-1.2, 0.0, 1.2); and VLI (from no violation to complete violation). Examinee ability or latent trait was pseudorandomly drawn from a standard normal distribution, and the b-parameter was estimated using a maximum likelihood procedure on generated test scores. Regardless of SS, TL, and TD, the b-parameter tended to...
Calcified ball thrombus in the left atrium

We experienced a case of calcified ball thrombus that was fixed to the atrial septum in the left atrium. This patient had no symptoms and no cardiac dysfunction. The thrombus was detected during preoperative work-up of a retroperitoneal tumor. The process of fixation to the atrial septum and calcification is unclear.
Synthesis of Surfactant-Templated Silica Films with Orthogonally Aligned Hexagonal Mesophase

Thin silica films with orthogonally aligned hexagonal close-packed cylindrical structure are synthesized by dip coating silica precursors and poly(ethylene oxide)−polyproplyene oxide (PEO−PPO) triblock surfactants (P123) onto modified glass slides. All films cast from this sol display 2D hexagonal pore structures (a ∼ 6.2 nm) under transmission electron microscopy (TEM). However, X-ray diffraction (XRD) shows that confining freshly deposited films between two chemically neutral modified slides completely aligns the pores toward the direction orthogonal to the substrate. Equally effective alignment is obtained by using slides modified with either a random PEO−PPO copolymer or P123 itself. The channels in films cast onto unmodified slides, onto modified slides which are exposed to air, or onto modified slides which are exposed to unmodified glass slides align at least partially parallel to the substrate. Parallel mesophase alignment is also observed in a control experiment with a sol containing the nonionic...
Single-channel recording from adult Brugia malayi

Lymphatic filariasis is a significant cause of morbidity in humans. One of the causative agents is Brugia malayi a clade III nematode. Current therapeutic agents are effective against the microfilaria but less so against the adults residing in the host lymphatics. A large number of anthelmintics act on nematode ion channels including the nicotinic receptors found on nematode somatic muscle. The purpose of this study was to develop a preparation from adult B. malayi that was amenable to patch-clamp recording to facilitate the study of the ion channels present in this organism. We also present a preliminary characterization of the single-channel properties of nicotinic receptors from the adult musculature.
Commentary: The evolution of evidence-based psychotherapy.

What has been identified as a revolution actually represents an evolution, stemming directly from the basic behavioral tenets of the early to mid 20th century. Cognitive-behavior approaches within behavior therapy are not really new. As early as the 1950s a substantial number of behaviorists saw a clear role for cognition and relied on hypothetical constructs to explain behavior. There are at least two major challenges for cognitive-behavior approaches. The first is the assurance of the validity and reliability of the measurement of both outcome and the cognitive factors that are presumed to serve as mediators of the observed effects. As the cognitive factors being studied become more complex, the measurement of the variables of interest becomes more difficult. The second challenge is to be open to new paradigms and approaches that may bring into question well-established concepts. The preeminence of the cognitive-behavioral approach is directly related to the fact that its concepts and methods can be subjected to empirical scrutiny. © 2004 Wiley Periodicals, Inc. J Clin Psychol.
The use of discretion in prison disciplinary committees

Prison disciplinary committees are faced with the formal role responsibility of adjudicating disciplinary cases in an equitable manner and the informal role responsibility of supporting the authority of the staff members who file charges of rule violations by inmates. Analysis of 630 disciplinary cases reveal that dispositional decisions vary according to the number of charged rule violations and that the pattern of the dispositional decisions can be explained by role conflict but not by the thesis that the cases vary in terms of the adequacy of the evidence supporting blameworthiness.
Stability and change in level of maternal depressive symptomatology during the first postpartum year.

Abstract Background: This study evaluated stability and change in the level of maternal depressive symptomatology over the course of the first postpartum year in a community cohort of 106 first-time mothers of full-term, healthy infants. Effects of diagnosed depression and infant gender were also assessed. Methods: At 2 months postpartum (intake), mothers were classified into one of two symptom groups on the basis of their total score on the Center for Epidemiological Studies–Depression Scale (CES-D): high (CES-D score ≥16, 46%) or normative (CES-D score=2–12, 54%). Mothers completed the CES-D again at 3, 6, and 12 months postpartum. At 12 months, maternal diagnostic status for major depression and related disorders was evaluated using the Diagnostic Interview Schedule-III–Revised. Results: Mothers in the High symptom group at intake continued to have significantly higher CES-D scores at 3, 6, and 12 months than mothers in the Normative symptom group at intake, and a third in the High symptom group at intake had a subsequent CES-D score above the clinical cutoff (≥16). Maternal CES-D scores were significantly correlated across visits. In regressions controlling for diagnostic status and infant gender, mothers’ CES-D score at the most recent prior assessment contributed significant unique variance to mothers’ CES-D score at each subsequent assessment. CES-D scores were higher at 3 months if mothers had diagnosed depression and were parenting a son, and higher at 12 months if mothers had both diagnosed depression and a prior, high CES-D score. Limitations: Findings may not generalize to multipara or high-risk cohorts. Conclusions: First-time mothers with high levels of depressive symptomatology at 2 months postpartum (especially those with diagnosed depression) are at increased risk of continuing to experience high levels of depressive symptomatology throughout the first postpartum year. Implications for preventative intervention services are discussed.
A Modification of Technique for Hysteroscopic Lysis of Severe Uterine Adhesions

ABSTRACT A useful technique to assist the surgeon in the treatment of Asherman's syndrome is described. This technique, using methylene blue to distend the uterine fundus, allows the surgeon to ide...
Fundamental optical absorption and photo-conduction in PbI2 single crystals

Abstract This paper describes measurements of the optical absorption of gel-grown PbI2 in the region from 0.5–15 μ and photoconductive measurements in the region of the absorption edge at about 0.525 μ. The edge is dichromatic, with a splitting of 0.048 eV which is explained in terms of a split valence band. The absorption edge of PbI2 for E ⊥ c is found to obey Urbach's rule for α = 50 cm−1 to 104 cm−1 in the temperature range 144–361°K and has a temperature dependence which may be represented by (ΔE/ΔT)α = (9.95-0.60 ln α) × 10 −4 e V °K . A well defined absorption band at 4.2 μ and an activation energy of 0.26 eV evaluated from the measurements of dark current vs. 1 T are attributed to a deviation from stoichiometry. The exciton effective mass in PbI2 is estimated to be M = 0.094 m0.
Age before beauty: an exploration of body image in African-American and Caucasian adult women

Research on body image emphasizes risks for eating disorders and typically involves young, Caucasian women. Few studies examine body image beyond the college years and there appears to be a disregard for the mature woman, as if self-acceptance of one's body is part of the aging process. Historically, it has been assumed that race is a protective factor against body dissatisfaction due to the perceived larger body ideal for women of color. Drawing upon interviews with Caucasian and African-American women from 20 to 80 years of age, this article explores body image across the lifespan. This analysis revealed that African-American and Caucasian women of all ages engage in private self-monitoring of their bodies and use strategies such as exercise, controlling food intake and cosmetic surgery to try and change the shape of their bodies. Therefore, it is evident that women across age and race categories are vulnerable to body dissatisfaction and disordered eating behaviors. Regardless of race, even mature wome...
Relationships between pain misconceptions, disability, patients' goals and interpretation of information from hand therapists

Abstract Introduction Patient interpretation of advice from hand therapists may be related to nonadaptive pain thoughts (automatic, overprotective, unduly pessimistic statements triggered by nociception and exacerbated by psychological distress). Purpose of the study This study aimed to determine whether there were correlations between participants' hand therapy goals, interpretation of advice from hand therapists, nonadaptive pain thoughts, and upper extremity-specific disability. Methods One hundred and five participants completed questionnaires assessing nonadaptive pain thoughts, upper extremity-specific disability, lessons from hand therapists, and hand therapy goals. Results Nonadaptive pain thoughts correlated with disability and were bi-directionally related to participant goals and interpretation of advice from hand therapists. Discussion Patients' nonadapative pain thoughts and the words/concepts used by hand therapists are both important in recovery from upper extremity illness. Conclusions Hand therapists should be mindful that nonadaptive pain thoughts are an important determinant of disability and that such thoughts can affect and be affected by their recommendations. Level of evidence n/a
Methamphetamine-induced selective dopaminergic neurotoxicity is accompanied by an increase in striatal nitrate in the mouse.

: Exposure to high doses of methamphetamine (METH), a major drug of abuse, may cause neuronal damage. Previous studies have implicated the role of peroxynitrite, produced by nitric oxide (NO) and reactive oxygen species, in dopaminergic neurotoxicity produced by METH in mice. The present article was undertaken to investigate if a neurotoxic regimen of METH is associated with changes in tissue levels of nitrate and nitrite, which are the stable products of NO. Administration of METH (5 mg/kg × 3) to Swiss Webster mice resulted in marked depletion of dopamine (DA) and DA transporter (DAT) binding sites but no change in 5-hydroxytryptamine (5-HT) and 5-HT transporter (5-HTT) binding sites in the striatum, amygdala, frontal cortex, and hippocampus, suggesting that METH causes selective neurotoxicity to DA nerve terminals. The concentration of nitrate in the striatum was increased by about two-fold after METH administration; however, no changes in nitrate concentration were detected in other brain regions that endured dopaminergic neurotoxicity. These findings suggest that (a) a neurotoxic regimen of METH produces selective increase in NO in the striatum, which may generate toxic species such as peroxynitrite, and (b) toxins other than NO-related derivatives may mediate dopaminergic neurotoxicity in the amygdala and frontal cortex.
Rescue from a two hit, high-throughput model of neurodegeneration with N-acetyl cysteine

Postmortem tissue from patients with neurodegeneration exhibits protein-misfolding stress and reduced proteasome activity. This hallmark burden of proteotoxic stress has led to the term "proteinopathies" for neurodegenerative diseases. Proteinopathies may also be exacerbated by previous insults, according to the two hit hypothesis of accelerated neurodegeneration. In order to model the response to two successive insults in a high-throughput fashion, we exposed the neuronal cell line N2a to two hits of the proteasome inhibitor MG132 and performed three unbiased viability assays. MG132 toxicity was synergistically exacerbated following sequential hits provided the first hit was high enough to be toxic. This accelerated viability loss was apparent by (1) a nuclear and cytoplasmic stain (DRAQ5+Sapphire), (2) immunocytochemistry for a cytoskeletal marker (α-tubulin), and (3) ATP levels (Cell Titer Glo). Ubiquitin-conjugated proteins were raised by toxic, but not subtoxic MG132, and were thus correlated with toxicity exacerbation at higher doses. We hypothesized that levels of autophagic and antioxidant defenses would be reduced with toxic, but not subtoxic MG132, explaining their differential impact on a second hit. However, proteins involved in chaperone-mediated autophagy were raised by toxic MG132, not reduced. Furthermore, inhibiting autophagy enhanced the toxicity of both subtoxic and toxic MG132 as well as of dual hits, suggesting that autophagic removal of cellular debris protected against proteasome inhibition. Two toxic hits of MG132 synergistically decreased the antioxidant glutathione. The glutathione precursor N-acetyl cysteine reversed this glutathione loss and prevented the toxic response to dual hits by all three assays. Dietary supplementation with N-acetyl cysteine benefits Alzheimer's patients and is currently undergoing clinical trials in Parkinson's disease. The present report is the first demonstration that this versatile compound is protective against synergistic loss of viability as well as of glutathione following unrelenting, sequential hits of proteotoxic stress as may occur in the diseased brain.
High colony-forming efficiency of primary human tumor cells cultured in the adhesive-tumor-cell culture system: Improvements with medium and serum alterations

The colony-forming efficiency (CFE) of primary human tumor cells cultured in the adhesive-tumor-cell culture system (ATCCS) using Ham's F12 (F12) or Eagle's minimum essential medium, alpha modification (alphaMEM) and culture medium supplemented with either swine, equine or bovine sera were compared. AlphaMEM supplemented with equine serum provided the highest CFE of the combinations. The CFE increase due to the change from F12 to alphaMEM was approximately 5-fold, and the increase due to the change in serum from swine to equine was approximately 2-fold. Cytokeratin staining showed that this increase was not due to fibroblast growth. The high-average CFE with alphaMEM, approximately 3%, means that an inoculum of only 2 X 10(3) cells is needed to achieve formation of approximately 65 colonies in control cultures, thereby increasing the performance of this system when used in a chemosensitivity assay.
“In the real world no one drops their standards for you”: Academic Rigor in A College Worker Education Program

When they graduate I want them to feel, “I went through a real thing, not an approximation of college, but I went through college and that means something!” (Adjunct Instructor) This article explores the complexity of providing an academically rigorous college education to adult students enrolled in a union-supported worker education program affiliated with a large urban public university. The author examines differences in student and faculty perspectives on academic rigor and considers how students' lack of academic preparation intersects with institutional constraints to impact academic standards. She examines the role of race, ethnicity, class, and gender in determining academic expectations and outcomes and explores the complex and, at times, conflicting relationship between care and academic rigor. She highlights the crucial role of institutional constraints in hindering the implementation of rigorous education for academically under-prepared students. The author argues that high academic standards ...
Sequence‐specific recognition of the internalization motif of the Alzheimer's amyloid precursor protein by the X11 PTB domain

The crystal structure of the phosphotyrosine‐binding domain (PTB) of the X11 protein has been determined, in complex with unphosphorylated peptides corresponding to a region of β‐amyloid precursor protein (βAPP) that is required for receptor internalization. The mode of binding to X11 of the unphosphorylated peptides, which contain an NPxY motif, resembles that of phosphorylated peptides bound to the Shc and IRS‐1 PTB domains. Eight peptide residues make specific contacts with the X11 PTB domain, and they collectively achieve high affinity ( K D = 0.32 μM) and specificity. These results suggest that, in contrast to the SH2 domains, the PTB domains are primarily peptide‐binding domains that have, in some cases, acquired specificity for phosphorylated tyrosines.
A technique for comparative light and scanning electron microscopy of the same deparaffinized microtomed section

SUMMARY Evaluation of various types of clear plastic support material for light and scanning electron microscopy of the same section was conducted. GelBond was found to be the most satisfactory among seven different types of plastic materials tested. It offers all of the advantages of glass slides for light microscopy while being thin and flexible enough to cut and sputter coat for SEM.
FPGA implementation and performance evaluation of an RFC 2544 compliant Ethernet test set

With the constant and rapid advances in microelectronics and networking technology, network service providers' needs for tuning up services, in order to attract more subscribers, have become more important. Ethernet technology has improved in terms of communication speed and has established itself as a standard enabling more recently throughput rates in the range of 1-100 Gbps. However, the need for quality services requires Ethernet testers to be not only standard compliant, but also meet performance criteria as specified by the standard. Performance criteria are difficult to prove and typically cannot be accomplished by software due to the limitations of the underlying general purpose hardware as well as the existence of many software layers. In this paper, we propose a design, an implementation and the performance verification achievements of an Ethernet tester compliant with the throughput and latency tests specified by the RFC 2544 for 10/100 Mpbs Ethernet networks. The results showed that the device designed achieved the performance criteria defined by the RFC while it was implemented in a Commercial Off-The-Shelf (COTS) low cost FPGA board. The performance was compared to an existent software implementation and the results showed that the usual limitations added by several hardware and software layers can be overcome by implementing a frame generator, monitor and media access (MAC layer 2) directly in an FPGA device.
Weighting Procedures for Ethnographic Random Samples

Repartions des poids pour les echantillons au hasard ethnographiques. Dans l'echantillonnage au hasard, le sociologue n'exerce aucune influence sur le choix de repondants. Au contraire, l'ethnographe choisit des repondants par rapport a leur valeur d'informateur. Cette etude presente "l'echantillonnage ethnographique au hasard" ou un echantillon est choisi comme en ethnographie mais avec une selection au hasard dans des strates semblables de repondants potentiels. Cette synthese garde la capacite d'adaptation de l'ethnographie en apportant la generalisibilite de l'echantillonnage au hasard. Le cadre d'echantillonnage ("sampling frame") comprend tous les repondants potentiels, mais a l'envers des enquetes habituelles, le cadre peut etre determine a la fin de l'etude. L'echantillonnage au hasard permet l'utilisation des techniques de repartions de poids pour determiner les caracteristiques du cadre. Cependant, la generalisation au-dela du cadre d'echantillonnage est problematique pour les populations mal ca...
Rapid reciprocal changes of rat hepatic glycolytic enzymes and fructose-1,6-diphosphatase following glucagon and insulin injection in vivo

Abstract Glucagon and insulin given intravenously produced rapid reciprocal changes in the activity of phosphofructokinase (PFK), pyruvate kinase (PK) and fructose diphosphatase (FDPase) in rat liver. Fructose diphosphate aldolase did not change. Glucagon increased FDPase and decreased PFK and PK activity. Insulin decreased FDPase and increased PFK and PK activity. The glucagon effect was associated with a marked increase in hepatic cyclic adenosine 3′,5′-monophosphate (cyclic AMP) concentrations. Insulin did not significantly alter hepatic cyclic AMP concentrations.
The Relationship of Young Children’s Motor Skills to Later Reading and Math Achievement

This study examined empirical evidence about the relationship between motor skills at the beginning of kindergarten and reading and mathematics achievement at the end of first grade, using the Early Childhood Longitudinal Study— Kindergarten cohort national dataset (N = 12,583). Results of hierarchical regression analyses demonstrated that early kindergarten motor skills, especially visual motor skills, add a small but unique amount of variance to achievement in reading and mathematics at the end of first grade even after controlling for initial skills and demographic information. Furthermore, Receiver-OperatingCharacteristic curve analyses showed that information from visual motor skills is useful in identifying children at risk for academic underachievement. The results suggest the importance of the role that motor skills can play in designing and implementing an early school achievement battery. The relationship between motor and cognitive skills has long been the subject of research in several fields. In child development, Piaget accorded sensorimotor skills a central role in children’s early cognitive development. According to Piaget’s (1952) developmental theory, motor skills contribute to infants’ active exploration of the environment, and it is through such actions that infants construct their knowledge of the world. Related studies demonstrated that infants’ experiences of self-produced locomotion (e.g., crawling) are related to such cognitive skills as object permanence and the
Military Accord, Media Discord: A Cross-National Comparison of UK vs US Press Coverage of Iraq War Protest

Although the UK and US were staunch allies before and during the Iraq War, differing sociopolitical milieus existed within the countries regarding support for the war. This cross-national content a...
Comparative studies on mannosylphosphoryl dolichol and glucosylphosphoryl dolichol synthases.

Abstract Factors affecting the synthesis of mannosylphosphoryl dolichol and glucosylphosphoryl dolichol hen oviduct microsomes were compared in order to gain insight into the properties of their respective synthases. A stabilized form of mannosylphosphoryl dolichol synthase, but not glucosylphosphoryl dolichol synthase, was released from microsomes by freezing the membranes after exposure to the detergent CHAPSO. The activation energy for mannosylphosphoryl dolichol synthesis in membranes was 9.4 kcal/mol over the range of 10–37°C; above 18°C the process of glucosylphosphoryl dolichol synthesis in membranes had a similar activation energy, 8.1 kcal/mol, but below 18°C the value was 16.7 kcal/mol. Tryptic digestion of sealed microsomes preferentially inactivated mannosylphosphoryl dolichol synthase; however, both synthases were equally inactivated in detergent-permeabilized microsomes. Periodate-oxidized UDP-Glc was used to probe the topological orientation of glucosylphosphoryl dolichol synthase in rat liver microsomes. Sealed microsomes treated with oxidized UDP-Glc were inactive in synthesis of glycosylphosphoryl dolichol. However, when these treated microsomes were permeabilized, glucosylphosphoryl dolichol synthase activity was readily detected. From these studies we conclude that although mannosyl- and glucosylphosphoryl dolichol synthases catalyze chemically similar reactions in the endoplasmic reticulum, they differ in several respects. These differences were interpreted in terms of a topological model in which the active sites of the two enzymes reside on opposite faces of the endoplasmic reticulum, with that of the glucosyl lipid synthase facing the lumen and that of the mannosyl lipid synthase facing the cytosol.
Critical Surface Density of the Superfluid Component in He 4 Films

It is shown that published third-sound measurements are in very good agreement with the theoretical result by Nelson and Kosterlitz that in the limit as $T\ensuremath{\rightarrow}{{T}_{c}}^{\ensuremath{-}}$ the ratio of the density per unit area of superfluid component to the critical temperature, ${T}_{c}$, is the universal constant $(\frac{2}{\ensuremath{\pi}}){(\frac{m}{\ensuremath{\hbar}})}^{2}{k}_{\mathrm{B}}$.
Enantioselective Transesterification by Candida antarctica Lipase B Immobilized on Fumed Silica

Enzymatic catalysis to produce molecules such as perfumes, flavors, and fragrances has the advantage of allowing the products to be labeled "natural" for marketing in the U.S., in addition to the exquisite selectivity and stereoselectivity of enzymes that can be an advantage over chemical catalysis. Enzymatic catalysis in organic solvents is attractive if solubility issues of reactants or products, or thermodynamic issues (water as a product in esterification) complicate or prevent aqueous enzymatic catalysis. Immobilization of the enzyme on a solid support can address the generally poor solubility of enzymes in most solvents. We have recently reported on a novel immobilization method for Candida antarctica Lipase B on fumed silica to improve the enzymatic activity in hexane. This research is extended here to study the enantioselective transesterification of (RS)-1-phenylethanol with vinyl acetate. The maximum catalytic activity for this preparation exceeded the activity (on an equal enzyme amount basis) of the commercial Novozyme 435(®) significantly. The steady-state conversion for (R)-1-phenylethanol was about 75% as confirmed via forward and reverse reaction. The catalytic activity steeply increases with increasing nominal surface coverage of the support until a maximum is reached at a nominal surface coverage of 230%. We hypothesize that the physical state of the enzyme molecules at a low surface coverage is dominated in this case by detrimental strong enzyme-substrate interactions. Enzyme-enzyme interactions may stabilize the active form of the enzyme as surface coverage increases while diffusion limitations reduce the apparent catalytic performance again at multi-layer coverage. The temperature-, solvent-, and long-term stability for CALB/fumed silica preparations showed that these preparations can tolerate temperatures up to 70°C, continuous exposure to solvents, and long-term storage.
Sharing authority: Student initiations during teacher-led read-alouds of information books

Abstract This study focuses on students' initiations during teacher-led read-alouds of information books in a U.S. urban first grade classroom. The teacher's use of interactive read-alouds challenges deficit constructions of poor, non-mainstream children and offers them multiple opportunities to direct the work and the talk of the classroom. By seeing the range of student initiations over the course of a school year, this study offers evidence of the ways these children shared authority with the teacher and thus were able to speak and act as experts. Providing students with multiple opportunities to speak and act as experts is essential if children are to be encouraged to become producers, not just consumers of knowledge. Information books and interactive read-alouds encourage such expert talk and action from students in classrooms.