cssi/SciSciGPT-SciSciNet huggingface dataset:
Manufacturing planning and execution software interfaces

Abstract Process planning and manufacturing execution systems provide two major functions in a product development cycle. Industries require the systems that support these two functions to be able to integrate with other related manufacturing systems, such as design, resource planning, production scheduling, and equipment control. However, there are information barriers to the integration of commercial systems in these areas. This paper presents an activity model for manufacturing execution and a set of foundation interfaces, identified in an object model, that have been developed to cope with the problem. The interfaces are intended to be a base from which they evolve as the new technology and industrial practices emerge.
Regulation of Auxin Levels in Coleus blumei by Ethylene

An investigation of the effects of ethylene pretreatment on several facets of auxin metabolism in Coleus blumei Benth "Scarlet Rainbow" revealed a number of changes presumably induced by the gas. Transport of indoleacetic acid-1-(14)C in excised segments of the uppermost internode was inhibited by about 50%. Decarboxylation of indoleacetic acid-1-(14)C by enzyme breis was not affected by the pretreatment. Levels of extractable native auxin in upper leaf and apical bud tissue of the pretreated plants were approximately one-half of those present in untreated plants. The rate of formation of auxin from tryptophan by enzyme breis from pretreated plants was approximately one-half that occurring in incubation mixtures containing the enzyme system from untreated plants. The conjugation of indoleacetic acid-1-(14)C in a form characterized chromatographically as indoleacetylaspartic acid was increased 2-fold in the upper stem region of plants pretreated with ethylene.
SU‐DD‐A1‐05: Treatment Planning of Prone Position Accelerated Partial Breast Irradiation Customized for Magnetic Resonance Imaging Guidance

Purpose: It is important to deliver an optimized dose distribution to an accurately delineated target volume for a successful accelerated partial breast irradiation (APBI) treatment. Breast magnetic resonance imaging(MRI) could improve lumpectomy delineation. We investigated treatment plans for CyberKnife and conventional C‐arm LINAC delivery of MRI‐guided APBI in prone position. Method and Materials: We acquired a CT scan of a patient positioned on a mechanical assembly with the same geometry as the dedicated MR coil to simulate the position during breast MRI acquisition. Ellipsoidal virtual PTV's of 4 cm were defined in the anterior part and in the lower outer quadrant of the right breast. Treatment plans were generated by inverse planning techniques for each system. For CyberKnife, we minimized beam directions from posterior to anterior to protect critical normal tissues(heart,lung and contralateral breast) and normalized the maximum dose to 120% of the prescription dose (38.5 Gy). For the conventional LINAC, we excluded any beams directed towards the critical normal tissues and normalized the plan to achieve 99% of the prescription coverage for 99% of PTV. Results: LINAC‐based plans resulted in maximum doses of 41.6 Gy in PTV and ⩽ 0.5 Gy in the critical normal structures. CyberKnife‐based plans led to 90% of the prescription dose coverage for 95% of PTV. Maximum doses were ⩽ 0.5 Gy in contralateral breast, ⩽ 1.9 Gy in heart, and ⩽ 4.2 Gy in both lungs. The fraction of normal ipsilateral breast tissue receiving ⩾ 37 Gy was 1% and 5% for CyberKnife and LINAC plans respectively. Conclusion: CyberKnife and LINAC generate treatment plans for MRI‐guided prone position APBI with acceptable dose distributions. The standard LINAC requires careful beam configuration to secure clearances between equipments. CyberKnife results in better conformity and slightly higher doses in the critical normal tissues.
Mayo International Spine Symposium 2010

This annual 5-day Continued Medical Education event featured the latest in new treatment strategies and techniques for orthopedists, neurosurgeons, physiatrists, primary care providers and other professionals involved in treating patients with spinal disorders. This year’s program content focused on: minimally invasive surgery, motion-preservation surgery, nonoperative spine care, value (quality/cost) and maintenance of certification self-assessment examination.
Sea Change: Interest‐based vs. cultural‐cognitive account of strategic choice in the 1890s

(1996). Sea Change: Interest‐based vs. cultural‐cognitive account of strategic choice in the 1890s. Security Studies: Vol. 5, No. 4, pp. 73-124.
Conceptual basis and clinical rationale for the development of a multidisciplinary weight management center.

Overweight (body mass index (BMI) 25 kg m−2) or obesity (BMI 30>kg m−2) affects more than two-thirds of Americans. Overweight and obesity are commonly associated with multiple coexisting conditions, such as hypertension, diabetes, dyslipidemia, cardiovascular disease, obstructive sleep apnea and cancer. Lifestyle modification can induce a modest weight loss, which is associated with the prevention or improvement of many of these comorbidities. A combination of diet, exercise and behavioral therapy is considered the cornerstone of treatment for all overweight and obese individuals. As the etiology and therapy of obesity is complex, what is needed for these patients is a multidisciplinary clinic where specialists from different disciplines share their knowledge and participate in the treatment of the obese patient.
Regulation of dendritic excitability by activity-dependent trafficking of the A-type K+ channel subunit Kv4.2 in hippocampal neurons

Voltage-gated A-type K+ channel Kv4.2 subunits are highly expressed in the dendrites of hippocampal CA1 neurons. However, little is known about the subcellular distribution and trafficking of Kv4.2-containing channels. Here we provide evidence for activity-dependent trafficking of Kv4.2 in hippocampal spines and dendrites. Live imaging and electrophysiological recordings showed that Kv4.2 internalization is induced rapidly upon glutamate receptor stimulation. Kv4.2 internalization was clathrin mediated and required NMDA receptor activation and Ca2+ influx. In dissociated hippocampal neurons, mEPSC amplitude depended on functional Kv4.2 expression level and was enhanced by stimuli that induced Kv4.2 internalization. Long-term potentiation (LTP) induced by brief glycine application resulted in synaptic insertion of GluR1-containing AMPA receptors along with Kv4.2 internalization. We also found evidence of Kv4.2 internalization upon synaptically evoked LTP in CA1 neurons of hippocampal slice cultures. These results present an additional mechanism for synaptic integration and plasticity through the activity-dependent regulation of Kv4.2 channel surface expression.
Hyperstriatum ventrale in pigeons: Effects of lesions on color-discrimination and color-reversal learning

Previous lesion studies of color-reversal learning in pigeons show that an impairment results when (1) the tectofugal visual pathway is damaged at either the thalamic level (nucleus rotundus) or the telencephalic level (ectostriatum), or (2) the thalamofugal visual pathway is damaged at the telencephalic level (the visual Wulst). An impairment does not result, however, when the thalamic source of thalamofugal input (n. opticus principalis thalami or OPT) to the visual Wulst is damaged. These results suggest that the visual Wulst plays a role in color-reversal learning as a consequence of visual information routed from the tectofugal pathway via other visual areas in the telencephalon. One such area is the hyperstriatum ventrale (HV). In the present study, after ablation of the medial and lateral regions of HV, pigeons were trained postoperatively to discriminate between two colors presented simultaneously. After reaching criterion, the pigeons were required to perform a series of discrimination reversals in which the positive and negative stimuli were interchanged. Lesions of medial HV resulted in impaired performance of a color-discrimination task (i.e. original learning), but did not affect discrimination reversal. An impairment in color-reversal learning resulted from combined damage to lateral HV and the fronto-thalamic tract (FT), which carries ascending visual input from OPT to the visual Wulst. No deficits were observed when either lateral HV or FT were damaged alone. These findings suggest that both the thalamofugal and tectofugal pathways provide the visual Wulst with visual input relevant to color-reversal learning.
Reversing the Gender Gap in Negotiations: An Exploration of Stereotype Regeneration

We examine how gender stereotypes affect performance in mixed-gender negotiations. We extend recent work demonstrating that stereotype activation leads to a male advantage and a complementary female disadvantage at the bargaining table (Kray, Thompson, & Galinsky, 2001). In the present investigation, we regenerate the stereotype of effective negotiators by associating stereotypically feminine skills with negotiation success. In Experiment 1, women performed better in mixed-gender negotiations when stereotypically feminine traits were linked to successful negotiating, but not when gender-neutral traits were linked to negotiation success. Gender differences were mediated by the performance expectations and goals set by negotiators. In Experiment 2, we regenerated the stereotype of effective negotiators by linking stereotypically masculine or feminine traits with negotiation ineffectiveness. Women outperformed men in mixed-gender negotiations when stereotypically masculine traits were linked to poor negotiation performance, but men outperformed women when stereotypically feminine traits were linked to poor negotiation performance. Implications for stereotype threat theory and negotiations are discussed.
Responses of synchronous L5178Y S/S cells to heavy ions and their significance for radiobiological theory.

Synchronous suspensions of the radiosensitive S/S variant of the L5178Y murine leukaemic lymphoblast at different positions in the cell cycle were exposed aerobically to segments of heavy-ion beams ($^{20}$Ne, $^{28}$Si, $^{40}$Ar, $^{56}$Fe and $^{93}$Nb) in the Bragg plateau regions of energy deposition. The incident energies of the ion beams were in the range of 460$\pm$95 MeV u$^{-1}$, and the calculated values of linear energy transfer (LET$\_\infty$) for the primary nuclei in the irradiated samples were 33$\pm$3, 60$\pm$3, 95$\pm$5, 213$\pm$21 and 478$\pm$36 keV $\mu$m$^{-1}$, respectively; 280 kVp X-rays were used as the baseline radiation. Generally, the maxima or inflections in relations between relative biological effectiveness (RBE) and LET$\_\infty$ were dependent upon the cycle position at which the cells were irradiated. Certain of those relations were influenced by post-irradiation hypothermia. Irradiation in the cell cycle at mid-G$\_1$ to mid-G$\_1$ + 3 h, henceforth called G$\_1$ to G$\_1$ + 3 h, resulted in survival curves that were close approximations to simple exponential functions. As the LET$\_\infty$ was increased, the RBE did not exceed 1.0, and by 478 keV $\mu m^{-1}$ it had fallen to 0.39. Although similar behaviour has been reported for inactivation of proteins and certain viruses by ionizing radiations, so far the response of the S/S variant is unique for mammalian cells. The slope of the survival curve for X-photons (D$\_0$ 0.27 Gy) is reduced in G$\_1$ to G$\_1$ + 3 h by post-irradiation incubation at hypothermic temperatures and reaches a minimum (D$\_0$ 0.51 Gy) at 25 $^\circ$C. As the LET$\_\infty$ was increased, however, the extent of hypothermic recovery was reduced progressively and essentially was eliminated at 478 keV $\mu m^{-1}$. At the cycle position where the peak of radioresistance to X-photons occurs for S/S cells, G$\_1$ + 8 h, increases in LET$\_\infty$ elicited only small increases in RBE (at 10% survival), until a maximum was reached around 200 keV $\mu m^{-1}$ At 478 keV $\mu m^{-1}$, what little remained of the variation in response through the cell cycle could be attributed to secondary radiations ($\delta$ rays) and smaller nuclei produced by fragmentation of the primary ions.
Pharmacologic transglutaminase inhibition attenuates drug-primed liver hypertrophy but not Mallory body formation

Mallory bodies (MBs) are characteristic of several liver disorders, and consist primarily of keratins with transglutaminase-generated keratin crosslinks. We tested the effect of the transglutaminase-2 (TG2) inhibitor KCC009 on MB formation in a mouse model fed 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). KCC009 decreased DDC-induced liver enlargement without affecting MB formation or extent of liver injury. TG2 protein and activity increased after DDC feeding and localized within and outside hepatocytes. KCC009 inhibited DDC-induced hepatomegaly by affecting hepatocyte cell size rather than proliferation. Hence, TG2 is a potential mediator of injury-induced hepatomegaly via modulation of hepatocyte hypertrophy, and KCC009-mediated TG2 inhibition does not affect mouse MB formation.
The need for phase-encoding flow compensation in high-resolution intracranial magnetic resonance angiography.

Purpose To demonstrate that the time delay between phase and frequency encoding and the presence of pulsatile blood flow in high-resolution time-of-flight (TOF) imaging of the intracranial arteries (especially near the circle of Willis) can distort the appearance of blood vessels and result in a cross-hatch—appearing artifact in surrounding tissue. Materials and Methods Two techniques to reduce the artifact, tri-directional flow compensation (3DFC) and elliptical-centric (EC) phase-encoding order, are investigated in five volunteer studies. Results 3DFC eliminates the pulsation-related artifacts and the vessel distortion. A residual amplitude variation artifact is observed. EC phase encoding nearly eliminates the pulsatile motion-related artifact, but it does not eliminate vessel distortion. Conclusion The combination of 3DFC and EC phase encoding appears to provide the greatest artifact reduction in the five volunteer studies performed. J. Magn. Reson. Imaging 2003;18:121–127. © 2003 Wiley-Liss, Inc.
Mobility of rhenium, platinum group elements and organic carbon during black shale weathering

This study investigates the effects of black shale weathering on the Re–Os isotope system, platinum group element concentrations and the degradation of organic matter. Samples from a weathering profile in Late Devonian (∼365 Myr) Ohio Shale show a pronounced decrease (∼77%) in organic carbon (Corg) near the present soil surface, relative to the interior portion of the outcrop. A similar trend is observed for total N (∼67% loss). Conversely, organic phosphorus (Porg) concentrations increase by ∼59% near the soil surface. The decrease in Corg is accompanied by a pronounced decrease in Re (∼99%) and, to a lesser extent, Os (∼39%). Palladium and Pt do not appear to be significantly mobile. The effects of Re and Os mobility on the Re–Os isotope system are significant: none of the samples plots on a 365 Myr isochron. Rather, the samples define a trend with a slope corresponding to an age of ∼18 Myr with an initial 187Os/188Os of ∼6.1. This indicates recent disturbance of the Re–Os system. Isotope mass balance calculations imply that the labile fraction of Os is significantly more radiogenic (187Os/188Os of ∼7.8) than the average of the unweathered samples (187Os/188Os of ∼6.4). Based on data from this study, the molar ratio of labile Re to Corg in Ohio Shale is estimated at 7×10−8. We estimate the present-day riverine, black shale-derived Re flux to seawater using literature data on Re burial in anoxic marine sediments, and assuming steady-state between Re release during black shale weathering and Re burial in anoxic marine sediments. Then, the labile Re/Corg observed in this study implies that ∼0.5 Tmol of Corg is released annually from weathering of black shales, a trace lithology in the continental crust. This flux corresponds to ∼12% of the estimated annual CO2 flux from oxidative weathering of sedimentary rocks. The labile molar Re/Os of ∼270 indicates that black shale weathering releases ∼130 mol Os per year, which accounts for ∼7% of the riverine Os input to seawater. The data from this study support the notion that the crustal cycles of labile Corg, Re and Os are tightly coupled. Gray shales, which are less Corg-, Re- and Os-rich, but much more abundant in the continental crust than black shales, are likely to be even more important continental sources of Re and Os to seawater.
A Single Molecule Kinetic and Thermodynamic Approach to Oligonucleotide Duplex Formation

The formation of the canonical double stranded helix of DNA and RNA, through oligonucleotide hybridization, is a ubiquitous process in biology. Here we describe a single molecule fluorescence resonance energy transfer (smFRET) study that probes the formation and dissociation of a short (6-9 base pairs) double stranded DNA duplex. Kinetic measurements on this construct reveal that rates of duplex formation are not diffusion limited. In fact, the rate constants of formation are 2-3 orders of magnitude slower than estimated with a simple diffusion model. Subsequently, the duplex formation/dissociation (kon and koff) rates were measured as a function of Na+ concentration and both were found to change in a sigmoidal fashion with [Na+]. The measured values of koff decreased by a factor of four (0.7(2) s-1 to 0.14(5) s-1) between 25 mM and 1 M Na+. Surprisingly, kon was found to be much more sensitive to the [Na+], increasing by more than a factor of 40 (0.6(6) s-1 to 4.4(6) s-1) over the same range. These changes combine give a >100 fold change in the unimolecular equilibrium constant (Keq). Finally, the temperature dependence of Keq was used to dissect the free energy of duplex formation (ΔG°) into its enthalpic (ΔH°) and entropic (ΔS°) components. While ΔH° remains negative under all conditions, increasing the [Na+] reduced the magnitudes of both ΔH° and ΔS°. Given that ΔG° decreases with increasing [Na+], the magnitude of ΔS° must decrease faster than the unfavorable reduction in the magnitude of ΔH°. These insights highlight the dynamic nature of DNA duplexes on the time scale (seconds to minutes) of many cellular processes. Additionally, these data may aid in developing and evaluating new methods for modeling the thermodynamics of DNA duplex formation.
More on the Social Rate of Discount

I. Introduction, 430. — II. Internal rates of return and the ranking of projects, 434. — III. Calculating the opportunity cost of capital, 440. — IV. Conclusions, 449.
Social Risks and Child Development in South Africa: A Nation's Program to Protect the Human Rights of Children

Poverty, violence, social inequality, rapid urbanization, the HIV epidemic, and an erosion of traditional values create a challenging environment for development in South Africa. The nation has responded with a range of efforts to promote child welfare, often through efforts to strengthen family functioning. The nation's struggles, failures, and successes at safeguarding the developmental rights of children and providing for their needs offer lessons to others about what can and must be done if they are to live up the obligations assumed as signatories to the United Nations Conventions on the Rights of the Child.
Polychelatsiloxane. 3. Mitt.: Untersuchungen zur thermischen beständigkeit

Die gut herstellbaren Polychelatsiloxane mit einer aliphatischen β-Diketonatgruppierung und einem Trimethylen-Zwischenglied zwischen Chelat und Silicium, zersetzen sich auch in reinem Zustand ab 200°C, wobei in erster Linie eine Spaltung der Trimethylenkette unter Bildung von Methan eintritt. Die Einfuhrung aromatischer Substituenten am Chelatring oder der Ersatz der Trimethylengruppe durch andere Zwischenglieder ist synthetisch schwierig und erbringt keine Erhohung der thermischen Stabilitat der Polymeren. Thermisch bestandige Chelate von phenolischen Chelatbildnern liesen sich nicht befriedigend in Siloxane einbauen. The thermal decomposition of poly-chelate-siloxanes with aliphatic diketonate groups and trimethylene bridges between the chelate and the silicon atom begins at 200°C. The decomposition starts with scission of the trimethylene, groups under formation of methane. Introduction of aromatic substituents at the chelate ring or incorporation of other linking bridges cause synthetic difficulties and brings no higher thermostability of the polymers. Thermally stable chelates from phenolic ligands could not be incorporated into polysiloxanes in a satisfying manner.
Effects of withdrawal from chronic amphetamine intoxication on exploratory and stereotyped behaviors in the rat

Rats were administered 3, 6, and 12 mg/kg of d-amphetamine s.c. twice daily on a weekly increasing staircase schedule. On days 1, 7, 14, and 28 after the last injection of amphetamine the animals were challenged with 1 and 3 mg/kg of d-amphetamine and their behavior was observed. The 7-, 14-, and 28-day withdrawn animals required less amphetamine than controls to induce stereotyped behaviors. However, it was found that withdrawn animals and control animals were equally sensitive to the effects of apomorphine. Reserpine pretreatment eliminated the differences between control and withdrawn animals. α-Methyl tyrosine pretreatment blocked the effects of 1 but not 3 mg/kg of d-amphetamine in the withdrawn animals. Possible chemical mechanisms underlying the change in amphetamine sensitivity in the withdrawn animals are discussed.
Nutritional intake in children with renal insufficiency: a report of the growth failure in children with renal diseases study.

This study was designed to assess sequentially the nutrient intake in children with chronic renal insufficiency and its relationship to body size, the level of renal failure, and growth velocity.The nutrient intake from 401 4-day food records obtained from 120 children with renal insufficiency over a 6-month observation period was analyzed. The height and weight were measured at the beginning and end of the observation period. The glomerular filtration rate was estimated from the height and serum creatinine.The mean caloric intake in these children was 80 +/− 23% (mean +/− SD) of the Recommended Dietary Allowance (RDA) for age. Fifty-six percent of the food records obtained from these children revealed a caloric intake that was less than 80% of the RDA. Caloric intake expressed as the %RDA for age decreased with increasing age. However, the mean caloric intake when factored by body weight was in the normal range. There was no correlation between caloric intake and height velocity. The mean protein intake ...
Longitudinal Gains in Civic Development through School-Based Required Service

Despite recent figures indicating that 26% of public high schools in the United States require student involvement in community service or service learning, there is little empirical evidence to support such policies. In the present study, successive cohorts of high school students, one without (n = 174) and two with a community service requirement (n = 312), were compared longitudinally on measures of civic attitudes and behaviors. Each cohort was divided according to individual students’ inclinations to serve voluntarily. Students already inclined to serve scored high on all measures throughout and showed no advantage after meeting the requirement. However, students who were less inclined to serve showed marked gains on three of four civic measures after completing their requirement. Whereas they scored as low as their less-inclined counterparts who had no requirement during grade 11, they differed from their counterparts after serving the mandated 40 hours during grade 12. This quasi-natural experiment provides support for the argument that a well-designed service program can have a clear benefit in civic development for nonself-selected youth.
Final /s/ retention and deletion in Spanish: The role of the speaker’s type of competence

Abstract This study investigates the variation in the articulation of postnuclear /s/ in Spanish as it is spoken today in northern Morocco. It analyzes how both retention and deletion of final /s/ are highly conditioned by the type of the speaker’s competence. Quantitative analysis proves that final /s/ is systematically deleted by Moroccan-born native speakers of Spanish while it is frequently maintained by educated nonnative Moroccans speakers of Spanish, usually speakers of Arabic and French as well. The results confirm the overall resemblance of native northern Moroccan Spanish to Andalusian varieties and the strong impact Spanish media is having on nonnative speakers, who tend to develop a more standard variety. The reasons for this difference are attributed to the phonological inventories accessible to the speakers, the processes of their acquisition of Spanish, the integrative and instrumental use they make of it in their daily lives, and also the overall awareness of and attitude towards the internal sociolinguistic dynamics in neighboring Spain.
A preliminary investigation of temperature errors in operational forecasting models

Abstract Temperatures taken from model output (FOUS reports) routinely transmitted by the National Centers for Environmental Prediction are tabulated to determine errors during three months in the ...
Evaluation of the inhibition of glycolytic enzymes by the neurotoxicant dimethylaminopropionitrile.

The neurotoxic aminonitrile dimethylaminopropionotrile (DMAPN) inhibits the crystalline glycolytic enzymes glyceraldehyde‐3‐phosphate dehydrogenase (CAPDH) and fructose‐6‐phosphate kinase (phosphofructokinase, PFK). Preincubation of CAPDH with the aminonitrile enhances the inhibition, indicating that the inhibition is irreversible. The overall bimolecular rate constant kiwas determined to be 2.42 ± 0.21 M−1 min−1. Dithiothreitol (DTT) partially protected the enzyme from inhibition. PFK is also inhibited by DMAPN, but the inhibition is reversible and noncompetitive with a K1 of 2.79 x 10−2 M. DMAPN does not inhibit lactate dehydrogenase (LDH), nor is GAPDH or PFK inhibited by 3,3'‐iminodipropionitrile (IDPN).
Closed-Loop Identification of Hammerstein Systems Using Iterative Instrumental Variables

Abstract A feedback connection of a Hammerstein system and a linear controller provides a good approach to modeling systems with actuator nonlinearity or input saturation during closed-loop experiments. This paper discusses closed-loop identification of Hammerstein systems where both input and output signals are correlated with noise, and time domain signals are related via a nonlinear map. The static nonlinearity and the linear dynamic system are parametrized independently by using triangle basis functions and rational functions respectively. The independent parametrization method causes over-parametrization of the Hammerstein system, but parameter separation is conducted using a singular value decomposition. An iterative Instrumental Variables (IV) method minimizing an (filtered) output error (OE) is proposed to identify system parameters. The proposed iterative IV identification method is applied to the experimental closed-loop time domain data from the servo actuator in a Quantum LTO-3 tape drive and the estimation result shows the effectiveness of the proposed algorithm.
Dopaminergic regulation of cone retinomotor movement in isolated teleost retinas. II: Modulation by γ-aminobutyric acid and serotonin

In the accompanying paper we reported that 3,4-dihydroxyphenylethylamine (dopamine) induced light-adaptive retinomotor movements in teleost photoreceptors and that this effect was mediated by D2 dopamine receptors located on the photoreceptors themselves. In this study, we investigated the effects on cone retinomotor movement of three agents that have been reported by others to modulate retinal dopamine release: gamma-aminobutyric acid (GABA), 5-hydroxytryptamine (5-HT, serotonin), and melatonin. We report here that the GABA antagonists bicuculline and picrotoxin induced light-adaptive cone contraction in dark-adapted green sunfish retinas cultured in constant darkness; thus they mimic the effect of light or exogenously applied dopamine. Since their effects were blocked by either the D2 dopamine antagonist sulpiride or by Co2+, it seems likely that these agents act by enhancing retinal dopamine release. The GABA agonist muscimol produced effects opposite to those of GABA antagonists. Muscimol inhibited light-induced cone contraction in previously dark-adapted retinas and induced dark-adaptive cone elongation in light-adapted retinas. These results suggest that in green sunfish retinas, as has been reported for other retinas, GABA inhibits dopamine release. 5-HT induced light-adaptive cone contraction in dark-adapted retinas; thus 5-HT also mimics the effect of light or exogenously applied dopamine. The effect of 5-HT was blocked by sulpiride, Co2+, or the 5-HT antagonist mianserin. These results suggest that 5-HT induces cone contraction by stimulating dopamine release. Melatonin neither inhibited dopamine-induced cone contraction in retinas cultured in the dark nor induced cone elongation in retinas cultured in the light. Our results suggest that both GABA and 5-HT (but not melatonin) affect cone retinomotor movements in green sunfish by modulating dopamine release: GABA by inhibiting and 5-HT by stimulating dopamine release. We report in the companion paper that dopamine induced contraction in isolated cone fragments. Together these observations strongly suggest that dopamine serves as the final extracellular messenger directly inducing light-adaptive cone retinomotor movement, and that GABA and 5-HT affect these movements by modulating dopamine release.
Adolescents' health beliefs are critical in their intentions to seek physician care.

Background The examination of predictors of adolescents' intentions to use health care for different types of health issues has received little attention. This study examined adolescents' health beliefs and how they relate to intentions to seek physician care across different types of health problems. Methods Two hundred ten high school students (54% females; 76.6% participation rate) completed a self-administered survey of four separate age- and gender-specific health case scenarios: an adolescent who has symptoms of pneumonia; smokes five cigarettes daily; plans to initiate sex; and has symptoms of depression. For each health scenario, participants rated the seriousness of the health problem, physician effectiveness, and intentions to seek physician care. Results Most adolescents believed all health problems were serious except for planning to initiate sex (P < 0.001). Adolescents believed that physicians were most effective in diagnosis and treatment for pneumonia, followed by cigarette use, depression, and sex, respectively (P's < 0.001). Adolescents' intentions to seek physician care were greatest for physical as compared to risk behavior or mental health problems (P < 0.001). Multiple regression analyses revealed that adolescents had greater intentions to seek physician care for cigarette, sex, and depression when they believed physicians were effective and they perceived these as health problems after controlling for age and gender (all P's < 0.001). Health beliefs explained 12% to 49% of the variance in intentions to seek care (all P's < 0.001). Conclusions Adolescents' health beliefs are important when understanding intentions to seek physician care. Health care use may be improved by increasing adolescents' beliefs that physicians are effective in areas other than physical health, including risk behaviors and mental health.
Do normal hemodynamics parameters in bariatric patients belie intrinsic myocardial dysfunction? A cardiovascular MRI study

Introduction Classical teachings describe adverse cardiovascular (CV) outcomes in patients with BMI>30 such that refined bariatric surgical approaches have evolved attempting to reduce the observed morbidity and mortality of obesity. However, recently, numerous investigations report a paradoxically more normal CV risk profile as assessed by standard clinical tools such as echocardiography, nuclear or catheterization.
Perceived Barriers and Facilitators for an Academic Career in Geriatrics: Medical Students’ Perspectives

There is a growing concern about a shortage of physician scientists. This problem is particularly severe in certain subspecialties such as geriatrics in general and geriatric psychiatry in particular. This study sought to obtain medical students’ perspectives on barriers and facilitators toward pursuing a career in academics and/or in geriatric psychiatry or geriatic medicine. The study surveyed 27 first-year medical students from six US medical schools, who had demonstrated a clear interest in academic geriatrics by completing a mentored summer research training program in geriatric medicine or geriatric psychiatry, funded by the National Institute on Aging. The survey included open-ended and close-ended questions about likely career choice and factors affecting it. Sixty percent of students reported they were likely to pursue an academic career, 44 % a career in geriatric psychiatry or geriatic medicine, and only 36 % a career in academic geriatrics. The most frequently perceived barriers were a lack of knowledge about academic careers and lack of exposure to geriatrics, financial concerns due to loan debts and low compensation, and negative impressions of research and of working with older adults. Facilitators included positive experiences with or positive impressions of research and research mentors and of older adults, and the growing demand for geriatric care. Attracting capable and motivated medical students to academic careers in fields such as geriatric psychiatry or geriatic medicine should be a priority in seeking to expand the number of physician scientists and to add to the health-care workforce in underserved subspecialty areas. Necessary approaches should include opportunities to work in academic settings; availability of sustained and dedicated mentorship; early, consistent, and positive exposure to older adults; and financial incentives.
Nonparticipation as Self-Censorship: Publicly Observable Political Activity in a Polarized Opinion Climate

In a polarized opinion climate, people may refrain from participating in publicly observable political activities that make them vulnerable to scrutiny and criticism by others who hold opinions that differ from their own. We took a dispositional approach to testing this claim by determining whether people who are relatively more influenced by the climate of opinion when choosing whether or not to voice an opinion, measured with the Willingness to Self-Censor scale [Hayes et al. International Journal of Public Opinion Research 17 (2005) 298], are also relatively less likely to engage in public political activities. In a poll of residents of the United States, we found that even after controlling for interest in politics, political ideology, ideological extremity, political efficacy, attention to political news, dispositional shyness, frequency of political discussion, and demographics, dispositional self-censors reported having engaged in relatively fewer public political activities over the prior 2 years compared to those less willing to censor their own opinion expression. These results are consistent with our interpretation of political participation as a social process that is governed in part by the social psychological implications of participation to the person. At a larger theoretical level, our findings connect the literature on opinion perceptions and opinion expression with research on political participation.
Observations on the Metabolism of Alcohol

The effect of ethanol on the in vitro deposition of cholesterol and on the kidney citrate content is presented. The rate of disappearance of ethanol from the blood of rabbits is accelerated by the administration of adenosine triphosphate or fructose, but not by the administration of Chlor-Trimeton®, Pro-Banthine®, or Dormison®.
Heterogeneous nucleation of γ′ in Al-Ag and Al-Ag (Cd or Cu) alloys

Abstract Transmission electron microscopy studies of heterogeneous nucleation of the metastable γ' phase were made in binary and ternary alloys of Al-5 at. % Ag, Al-4.8 at. % Ag-0.15 at. % Cd and Al-4.8 at. % Ag-0.2 at. % Cu. Heterogeneous nucleation of γ' was found to be associated with four types of dislocations regardless of the quenching treatment or alloy additions which were used. Nucleation was found to occuron: 1. (a) jogged dislocations; 2. (b) helical dislocations; 3. (c) dislocation loops; 4. (d) heterogeneous climbsources. Only one nucleation mechanism was found to be unique to the ternary alloys: that of nucleation on heterogeneous climb sources.
Synthesis and CMC Determination of a Series of Aliphatic Diamines

Fifteen aliphatic diamines substituted with one long alkyl chain (C10-C18), a varying number of methylene groups separating the nitrogens (two to six), and various aliphatic substituents were synthesized and their CMC's were determined. While the length of the long alkyl chain plays a dominant role in influencing the CMC, the other N-alkyl substituents as well as the length of the methylene chain separating the two nitrogens of the diamine are significant factors.
High-performance liquid chromatography separation of phospholipid classes and arachidonic acid on cyanopropyl columns

An HPLC method for the separation and analysis of arachidonic acid and eight phospholipid classes is described: phosphatidylglycerol, phosphatidylinositol, cardiolipin, phosphatidylserine, phosphatidylethanolamine, phosphatidylcholine, sphingomyelin, and 2-lysophosphatidylcholine. The separation is carried out at 60 degrees C on 2 cyanopropyl columns using a gradient of acetonitrile and 5 mM sodium acetate (pH 5.0). Cyanopropyl columns require a lower proportion of water in the mobile phase to elute the more polar phospholipids than other types of columns and are thus less prone to equilibration problems. The method is highly reproducible (average coefficient of variation for each retention time less than or equal to 3.5%) and permits analysis of peaks by phosphorus content. Data obtained by analyzing lipid extracts from rat alveolar macrophages prelabeled with [G-3H]-arachidonic acid were analyzed by this HPLC method and compared to standard analysis by TLC. There was a significant correlation between the radioactivity profiles obtained with the two chromatographic methods (HPLC versus TLC) by linear regression analysis [HPLC = 0.83 (TLC) + 3.58, n = 25, r = 0.95, P less than 0.001].
Email Surveillance Using Non-negative Matrix Factorization

In this study, we apply a non-negative matrix factorization approach for the extraction and detection of concepts or topics from electronic mail messages. For the publicly released Enron electronic mail collection, we encode sparse term-by-message matrices and use a low rank non-negative matrix factorization algorithm to preserve natural data non-negativity and avoid subtractive basis vector and encoding interactions present in techniques such as principal component analysis. Results in topic detection and message clustering are discussed in the context of published Enron business practices and activities, and benchmarks addressing the computational complexity of our approach are provided. The resulting basis vectors and matrix projections of this approach can be used to identify and monitor underlying semantic features (topics) and message clusters in a general or high-level way without the need to read individual electronic mail messages.
Survival after aortic valve replacement for aortic stenosis: does left ventricular mass regression have a clinical correlate?

Aim The effects of post-operative left ventricular mass regression (LVMR) on clinical outcome after aortic valve surgery remains to be established. This study was intended to establish the impact of patient characteristics on post-operative survival in patients referred for aortic valve replacement (AVR), with particular regard to LVMR. Methods and results Two hundred and sixty consecutive cases submitted to aortic valve replacement for valvular stenosis were prospectively followed for a mean of 28±9 months. Baseline, characteristics and extent of LVMR were tested for association with survival by uni- and multivariable analysis. Ten deaths occurred during hospital stay and 52 during out-of-hospital follow-up. Mean left ventricular mass decreased from 190±43 to 158±70 g/m2 ( P <0.001). Older age, advanced functional class, hypertension, reduced left ventricle ejection fraction, and high pre-operative left ventricular mass index were associated with reduced survival. Overall the extent of LVMR did not influence the clinical results, while only early (<6 months) LVMR was weakly associated with mid-term outcome. Conclusion Survival after aortic valve surgery is mainly determined by the pre-operative functional cardiac and systemic status. The extent of LVMR does not correlate with clinical outcome, whereas aggressive treatment of hypertension may improve post-operative survival.
Differential response of muscle phosphocreatine to creatine supplementation in young and old subjects.

This study compared the effects of short-term creatine supplementation on muscle phosphocreatine, blood and urine creatine levels, and urine creatinine levels in elderly and young subjects. Eight young (24 +/- 1.4 years) and seven old (70 +/- 2.9 years) men ingested creatine (20 g day-1) for 5 days. Baseline muscle phosphocreatine measurements were taken pre- and post-supplementation using nuclear magnetic resonance spectroscopy (NMR). On the first day of supplementation subjects had blood samples taken immediately before and hourly for 5 h following ingestion of 5 g of creatine, and a pharmacokinetic analysis of plasma creatine levels was conducted. Twenty-four hour urine collections were conducted for 2 days prior to the supplementation period and for 5 days during supplementation. Old subjects had significantly higher baseline plasma creatine levels than young subjects (68.5 +/- 12.5 vs. 34.9 +/- 4.7 micromol L-1; P < 0.02). There were no significant differences between groups in plasma creatine pharmacokinetic parameters (i.e. area under the curve, elimination rate constant, absorption rate constant, time to maximum concentration, and maximum concentration) following the 5 g oral creatine bolus. Urine creatine, assessed pre and on 5 days of supplementation, increased (P < 0.001), with no difference between groups. Urine creatinine did not change as a result of creatine supplementation. Young subjects showed a significantly greater increase in muscle phosphocreatine compared with old subjects, and post-supplementation muscle phosphocreatine levels were greater in young subjects (young 27.6 +/- 0.5; old 25.7 +/- 0.8 mmol kg-1 ww) (P=0.02). There were no differences in blood or urine creatine between groups in response to supplementation, but old subjects had a relatively small increase (young 35% vs. old 7%) in muscle phosphocreatine after supplementation.
Quantification of the effect of kVp on edge-enhancement index in phase-contrast radiography

This study was performed to measure the dependence of edge-enhancement in polychromatic phase-contrast radiography on x-ray tube operating voltage. Measurements of edge enhancement were made at tube voltages from 40 to 86 kVp using a tungstenanodex-ray tube with a nominal focal spot size of 100 micrometers. A relatively weak attenuating, sharp edge consisting of a thin lucite sheet (3 mm) in air was imaged utilizing phase-contrast radiography (PC-R). PC-R images were acquired at different radiographic techniques in which x-ray tube voltage was varied from 40 to 86 kVp. The image receptor was a single emulsion x-ray mammography cassette. Optical density profiles across the edge of the object were obtained using a film digitizer and edge-enhancement indices were calculated. Increasing kVp resulted in a gradual decrease of the edge-enhancement index. Even at the highest kVp (86), however, important edge-enhancement effects were evident. While there is some degradation in the edge-enhancement effect of phase-contrast radiography at higher kVps, the decrease from 40 to 86 kVp is relatively small (11%). Our results suggest that further investigation into the role of phase-contrast imaging at higher kVp values for the purpose of patient dose reduction while still realizing the advantage of phase-contrast effects for improved soft-tissue detectability is warranted.
Gene expression of the lysophosphatidic acid receptor 1 is a target of transforming growth factor beta.

The lysophosphatidic acid (LPA) receptor LPA1/Edg2 is the first identified LPA receptor. Although its wide tissue distribution and biological functions have been well studied, little is known about how LPA1 is transcriptionally regulated. In the current study, we showed that LPA1 is a physiological target of transforming growth factor beta (TGFβ)-mediated repression. In both normal and neoplastic cells, TGFβ inhibits LPA1 promoter activity, LPA1 mRNA expression, and LPA1-dependent chemotaxis and tumor cell invasion. Knockdown of the TGFβ intracellular effector Smad3 or Smad4 with lentivirally transduced shRNA relieved these inhibitory effects of TGFβ. Interestingly, the LPA1 promoter contains two potential TGFβ inhibitory elements (TIEs), each consisting of a Smad binding site and an adjacent E2F4/5 element, structurally similar to the TIE found on the promoter of the well-defined TGFβ target gene c-myc. Deletion and point mutation analyses indicate that the distal TIE located at 401 bp from the transcription initiation site, is required for TGFβ repression of the LPA1 promoter. A DNA pull-down assay showed that the -401 TIE was capable of binding Samd3 and E2F4 in TGFβ-treated cells. TGFβ-induced binding of the Smad complex to the native -401 TIE sequence of the LPA1 gene promoter was further verified by chromatin immunoprecipitation assays. We therefore identified a novel role of TGFβ in the control of LPA1 expression and LPA1-coupled biological functions, adding LPA1 to the list of TGFβ-repressed target genes.