cssi/SciSciGPT-SciSciNet huggingface dataset:
Stereospecific analysis and mass spectrometry of triacylglycerols fromarabidopsis thaliana (L.) heynh. columbia seed

Arabidopsis thaliana continues to be an excellent model organism for studying plant molecular genetics and biochemistry. In particular, the generation and analysis of mutant lines has facilitated the study of fatty acid biosynthesis, lipid bioassembly and the regulation of these processes. In view of its importance in understanding the pathways specific to seed storage lipid biosynthesis, we report here, for the first time, stereospecific and mass spectral analyses of the triacylglycerols present inA. thaliana (L.) Heynh. Columbia wild-type seed. The use of NH4+-chemical-ionization mass spectrometry/mass spectrometry is described as a powerful technique in analyzing even trace amounts of individual triacylglycerol species.
Cytochrome P-450-dependent oxidation of progesterone, testosterone, and ecdysone in the spiny lobster, Panulirus argus.

Abstract Experiments were performed to determine the ability of the cytochrome P -450 present in hepatopancreas microsomes from the spiny lobster, Panulirus argus , to catalyze oxidation of progesterone, testosterone, and ecdysone. Preparations of hepatopancreas microsomes fortified with NADPH cytochrome P -450 reductase from pig liver efficiently catalyzed NADPH-dependent 16α- and 6β-hydroxylation of progesterone and testosterone, and 21-hydroxylation of progesterone. These products were also found if NADPH and NADPH cytochrome P -450 reductase were replaced by cumene hydroperoxide. Cytochrome P -450 purified from hepatopancreas microsomes catalyzed NADPH- and reductase-dependent 16α-hydroxylation of progesterone and testosterone 10 times more rapidly than the original microsomal preparation. While ecdysone was not a substrate for the hepatopancreas microsomal cytochrome P -450, low ecdysone 20-monooxygenase activity was found in hepatopancreas mitochondria. Further studies showed that homogenates of green gland, ovaries, and testes had higher ecdysone monooxygenase activities than hepatopancreas, and that the activity in green gland was localized in mitochondria.
Quantitative study of the tectally projecting retinal ganglion cells in the adult frog. II. Cell survival and functional recovery after optic nerve transection

It is known from previous work that ganglion cells disappear from the retina in significant numbers during optic nerve regeneration in the adult frog, In the present study, the population sine of surviving ganglion cells that have returned axon terminals to the correct tectal loci was estimated by counts of retrogradely labeled cells in retina-flat-mounts after tectal injections of HRP. Bilaterally symmetric injections were delivered to allow comparison of the normal and affected retinas. The frogs studied had regenerated the left optic nerve and had visually guided behaviors initiated by the recovered eye (see below). The proportion of tectally projecting ganglion cells in the normal retinas and in retinas of normal frogs studied in parallel ranged from 83–86% (Singman and Scalia: J. Comp. Neurol. 302: 792–809, 1991), In the affected retinas, the subpopulation of tectally projecting cells was reduced by 40–90% after regeneration, and the relative size of this subpopulation ranged from 67–86%. The optic tectum was injected unilaterally in one specimen, on the side ipsilateral to the regenerated (left) optic nerve. The HRP-labeled ganglion cells in the ipsilateral (left) retina accounted for only 0.8% of the surviving ganglion cells in this animal, whereas it was previously found that the ipsilateral tectally projecting ganglion cells normally amount to 0.9–2.3% (Singman and Scalia, op. cit.) In frogs recovering from transection of the left optic nerve, the frequency, latency, and accuracy of the prey-acquisition responses initiated by the recovering eye were compared with those initiated by the normal eye. Mealworms or lure dummies were used to stimulate prey acquisition. In one experiment, the stimuli were presented unilaterally in the monocular fields of frogs permitted to use both eyes. Prior to the fourteenth postoperative week, the affected eye initiated responses of abnormally long latency and low frequency. In contrast, responses initiated by the affected eye after 14 weeks appeared to be normal in all respects. In another experiment, the normal eye was sutured shut in some frogs recovering for at least 24 weeks and then the affected eye was retested. The affected eye was capable of consistently initiating brisk and accurate prey acquisition. In a final experiment, two stimuli were presented simultaneously in bilaterally symmetric regions of the monocular fields of frogs surviving at least 42 weeks. These fully recovered frogs showed no preference for using either the normal or the recovered eye. Despite severe loss of tectally projecting ganglion cells during optic nerve regeneration, frogs are capable of apparently normal visual responses in prey acquisition tests.
Social Structure and Citizenship: Examining the Impacts of Social Setting, Network Heterogeneity, and Informational Variables on Political Participation

In this study, we develop a model of the interplay between sociostructural determinants of an individual's discussion behavior, such as the setting of primary discussion networks (work, church, and volunteer groups) and the nature of discussion (i.e., level of exposure to non-like-minded ideas), and individual-level outcomes, such as hard news media use, political knowledge, and participation in political processes. In doing so, we synthesize many of the different and sometimes competing models that political communication scholars have used to examine the link between more macroscopic sociological variables and the individual-level behaviors that political scientists often focus on. Data to test our theoretical model come from a national telephone survey conducted in October and November 2002. Our analysis showed that the social setting in which citizens discuss politics is an important antecedent of political participation. Discussion networks as part of volunteer groups, for example, indeed serve as im...
Gas absorption during ion-irradiation of a polymer target

Abstract The presence of a high partial pressure of deuterated water in the vacuum of the scattering chamber of an MeV ion accelerator system was shown to promote the incorporation of deuterium into a thin polyimide target subjected to 1.3 MeV 4He+ irradiation. When the background pressure in the chamber was low, 2.7 × 10−5 Pa (2 × 10−7 Torr), the polyimide was shown by forward recoil spectrometry to evolve hydrogen when ion bombarded. This was an expected, and commonly observed, phenomenon. However, when the pressure in the scattering chamber was raised to 1.3 × 10−2 Pa (1 × 10−4 Torr) by the addition of D2O vapor through a leak valve, deuterium was readily incorporated into the target in the ion-irradiated area. The degree to which the polyimide film absorbed gas from the vacuum of the scattering chamber was unexpected. The deuterium/hydrogen atomic concentration ratio reached 0.235 after a dose of 3.5 × 1015 ions/cm2. The absorption of deuterium was accompanied by blistering in the polyimide at high ion fluences.
Determination of the magnetite-water equilibrium oxygen isotope fractionation factor at 350°C: A comparison of ion microprobe and laser fluorination techniques

Abstract A Cameca 4f ion microprobe has been used in conjunction with laser and conventional analytical techniques to measure the oxygen isotope fractionation between magnetite and water at 350°C. A set of experiments in which large (10–200 μm) magnetite crystals were grown from fine grained (0.2–2 μm) hematite starting material using four different isotopically labelled waters yields a value of 1000 In α(mt-w) = −8.47 ± 0.23, as determined by bulk oxygen extraction using laser fluorination. The value from the ion microprobe determination based on replicate analysis of magnetite single crystals is −8.60 ± 0.65. The bulk analysis of one of the set of four experiments was used as an internal ion microprobe standard. The good agreement between the two techniques suggests that ion microprobe analyses may permit determination of isotope fractionation factors in experiments involving only a few percent of overall exchange.
Rapid annealing in irradiated CMOS transistors

Data characterizing the transient annealing of the gate threshold voltage of contemporary CMOS transistors following exposure to pulsed ionizing radiation are presented and discussed. Devices tested during the study include those fabricated on both bulk silicon and silicon-on-sapphire substrates. Silicon dioxide and aluminum oxide gate dielectrics are evaluated. Leakage current phenomena associated with charge formation in dielectric substrates or dielectric isolation layers are also considered.
Robustness, evolvability, and neutrality.

Biological systems, from macromolecules to whole organisms, are robust if they continue to function, survive, or reproduce when faced with mutations, environmental change, and internal noise. I focus here on biological systems that are robust to mutations and ask whether such systems are more or less evolvable, in the sense that they can acquire novel properties. The more robust a system is, the more mutations in it are neutral, that is, without phenotypic effect. I argue here that such neutral change – and thus robustness – can be a key to future evolutionary innovation, if one accepts that neutrality is not an essential feature of a mutation. That is, a once neutral mutation may cause phenotypic effects in a changed environment or genetic background. I argue that most, if not all, neutral mutations are of this sort, and that the essentialist notion of neutrality should be abandoned. This perspective reconciles two opposing views on the forces dominating organismal evolution, natural selection and random drift: neutral mutations occur and are especially abundant in robust systems, but they do not remain neutral indefinitely, and eventually become visible to natural selection, where some of them lead to evolutionary innovations.
Abstract 2547: NCI-60 combination screening matrix of approved anticancer drugs

Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Anticancer drugs are rarely curative as single agents, thus most treatment regimens utilize a combination of agents. Selection of rational combinations based upon presumed mechanisms of action is an active area of research. Nonetheless, treatment regimens may have built up over time by addition of new agents to existing standards of care. In order to establish a framework for extending our understanding combination therapy, we have initiated an additional approach: the systematic testing of all pairwise combinations of FDA-approved anticancer drugs in the NCI-60 panel of human tumor cell lines. About 100 small molecule drugs are approved for cancer treatment worldwide – testing all 5000 pairwise combinations in each of 60 cell lines will require 300,000 experiments. Combinations are tested at 3 or more concentrations of each agent, and single agents are tested on the same plates, requiring ∼ 5 million wells. To date, about 100 pairs of drugs have been tested in the NCI-60 in a pilot phase – the high-throughput phase has just begun. Some combinations of drugs, such as bortezomib combined with cladribine, show better than single agent activity in nearly all cell lines tested. Other combinations, such as doxorubicin plus lapatinib, show more restricted benefit, with some cell lines showing enhanced growth inhibition or cell kill, while in other cell lines the combination is antagonistic or identical to the more active single agent. The NCI-60 panel of cell lines has been extensively molecularly characterized, with publicly available data including gene mutation, DNA copy number, DNA methylation, and expression of mRNA, protein and microRNA. The patterns of cell line sensitivity for a particular drug combination can be used to probe these molecular characterization data, generating hypotheses about potential predictive markers and/or mechanisms of action. Probing the doxorubicin plus lapatinib patterns reveals a strong correlation with MDR activity, with high MDR expressing lines showing enhanced combination activity. The most promising combinations identified from NCI-60 testing are being tested in vivo to determine the therapeutic index. Already 2 combinations have demonstrated promising xenograft activity. The combination screening data, along with tools to analyze the data, will be made available to the public through the NCI web site. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2547. doi:10.1158/1538-7445.AM2011-2547
Coworker attributes as potential correlates to the perceptions of older workers' job performance: An exploratory study

This study examined coworker attributes as potential correlates to the perceptions of older workers' job performance. It was found that increased education, more positive attitudes toward retirement, and experience working with older workers might lead to more positive perceptions of older workers' job performance.
A PENSION DECISION MODEL FOR THE EMPLOYER

Recently, the Financial Accounting Standards Board (FASB) reevaluated accounting for pension plans. The issue is emotional and highly political in nature. The FASB attempted to justify its approach on the basis of measuring economic activity, but it failed to provide much in the way of analytical support. This paper provides a managerial decision model and an economic basis for the existence of pension plans. A pension plan is described as a cost-saving, risk-sharing, incentive contract. The analysis is developed using agency theory. The model presented here meets three suggested objectives of an employer: 1. Maximization of utility through the maximization of profit 2. Ability to conform the risk characteristics of an employment contract to the risk characteristics of the employer 3. Diversification of the risk inherent in the employment contract Profit is maximized by producing cost savings associated with employee tenure and loyalty. Sharing cost savings with employees (i.e., offering a pension plan) meets the above objectives. The employer determines the optimal sharing rate for the expected cost savings. An examination of the employer's underlying decision process reveals implications for pension plan accounting which generally are consistent with and support the FASB's Statement of Financial Accounting Standards No. 87 [5].
Characterization of hydrofluoric acid treated Y–Ba–Cu–O oxides

Effects of hydrofluoric acid (HF) treatment on the properties of Y–Ba–Cu–O oxides were investigated. No obvious etching of bulk Y–Ba–Cu–O and no degradation of zero resistance temperature were observed even though the oxides were placed into 49% HF solution for up to 20 h. Surface passivation of Y–Ba–Cu–O due to HF immersion was verified by subsequent immersion of Y–Ba–Cu–O in water. A thin layer of amorphous fluoride formed on the surface of the Y–Ba–Cu–O during HF treatment, which limited further reaction between Y–Ba–Cu–O and HF, and later reaction with water. Thin film Y–Ba–Cu–O was passivated by HF vapors and showed no degradation in T c -zero after 30 min immersion in water. The properties of the surface layer of Y–Ba–Cu–O oxide after HF treatment are reported from Auger electron spectroscopy, x-ray diffraction, and scanning electron microscopy studies.
Predicting Condom Use Attitudes, Norms, and Control Beliefs in Hispanic Problem Behavior Youth: The Effects of Family Functioning and Parent–Adolescent Communication About Sex on Condom Use

Hispanic problem behavior youth are at an increased risk of engaging in HIV risk behaviors, including low condom use. However, relatively little research has examined factors that affect condom use in this population. Although research indicates that family processes, such as higher levels of family functioning and open parent-adolescent communication about sex, and condom use attitudes, norms, and control beliefs as depicted by the theory of planned behavior have an effect on condom use behaviors, the combination of the two factors has received minimal attention. The purpose of this study was to examine the effect of family functioning on condom use intentions and behaviors through communication about sex and condom use attitudes, parental norms, and control beliefs. A cross-sectional study of 171 predominately male (73.1%) sexually active Hispanic problem behavior adolescents (mean age = 14.88 years) was conducted. Structural equation modeling was used to test the study hypothesis. Findings largely support the overall model and suggest that family functioning had an indirect effect on condom use intention and behavior through communication about sex, condom use attitudes, and control beliefs. Family functioning, however, did not have an indirect effect on condom use intention and behavior through communication about sex and parental norms. Implications for prevention science and future research are discussed.
Isolating critical cases for reciprocals using integer factorization

One approach to testing and/or proving correctness of a floating-point algorithm computing a function f is based on finding input floating-point numbers a such that the exact result f(a) is very close to a "rounding boundary", i.e. a floating-point number or a midpoint between them. We show how to do this for the reciprocal function by utilizing prime factorizations. We present the method and show examples, as well as making a fairly detailed study of its expected and worst-case behavior. We point out how this analysis of reciprocals can be useful in analyzing certain reciprocal algorithms, and also show how the approach can be trivially adapted to the reciprocal square root function.
Clustering dynamics in water/methanol mixtures: a nuclear magnetic resonance study at 205 k<T<295 k.

Proton nuclear magnetic resonance (1H NMR) experiments have been performed to measure the spin−lattice, T1, and spin−spin, T2, relaxation times of the three functional groups in water/methanol mixtures at different methanol molar fractions (XMeOH = 0, 0.04, 0.1, 0.24, 0.5, 1) as a function of temperature in the range 205 K < T < 295 K. The measured relaxation times in the mixtures, at all the methanol molar fractions, are faster than those of pure water and methanol because of strong interactions, resulting in a complex hydrogen bonding dynamics that determines their thermodynamic properties. In particular, we observe how the interplay between hydrophobicity and hydrophilicity changes with temperature and influences the peculiar thermal behavior of the NMR relaxation times of the solution. The obtained results are interpreted in terms of the existence of stable water−methanol clusters at high temperature whereas, upon cooling to low temperature, clusters of single species are present in the mixture.
Radiocarbon ages of pre-bomb clams and the hard-water effect in Lakes Michigan and Huron

Five radiocarbon ages, all determined by accelerator mass spectrometry, have been obtained for two pre-bomb bivalves from Lake Michigan and one from Lake Huron. After correcting those ages for the fractionation of14C in calcite and for the radioactively inert CO2 in the atmosphere, we find residual ages, caused by the hard water effect, of about 250 years for Lake Michigan and 440 years for Lake Huron.
The Association Between High-Dose Diuretics and Clinical Stability in Ambulatory Chronic Heart Failure Patients

Abstract Objective In chronic heart failure (HF), diuretic doses increase as the disease progresses, often after hospitalization for instability, and have been associated with worsening renal function and increased mortality. Methods and Results A prospective observational analysis of 183 patients in an advanced HF clinic stratified at baseline by diuretic dose (low dose ≤ 80 mg, high dose > 80 mg furosemide equivalent) was performed. All patients were followed for 1 year, and the primary outcome was a combined HF event of admission for HF, cardiac transplant, mechanical cardiac support, or death. Compared with patients taking low-dose diuretics (n = 113), patients taking high-dose diuretics (n = 70) had more markers of increased cardiovascular risk and were more likely to have a history of recent instability (33% vs 4.4% in low dose, P 001). High doses of diuretics were a strong univariate predictor of subsequent HF events (hazard ratio 3.83, 95% confidence interval 1.82–8.54); however, after adjustment for clinical stability, diuretic dose no longer remained significant (hazard ratio 1.53, 95% confidence interval 0.58–4.03). Conclusion High-dose diuretics may be more of a marker than a cause of instability. A history of HF stability during the past 6 months is associated with an 80% lower risk of an HF event during the next year, independently of baseline diuretic dose.
Conization and early diagnosis of carcinoma of the cervix

C ARCINOMA of the cervix is the most common maIignant Iesibn in the femaIe. Twenty-seven to 30 per cent (MartzIoff, WeIch, and Orth) of a11 carcinomas in the femaIe are uterine carcinomas of which 80 to 97 per cent (KobIanck, Backer, BIumenfeId) originate in the cervix. Therefore, we understand the great attention paid to the probIems of diagnosis and treatment of this particuIar type of carcinoma. The earIy diagnosis of the beginning carcinomatous Iesion of the cervix is absoIuteIy essentia1 for its successfu1 treatment. The tragedy of cervical carcinoma lies in the fact that the patient is frequentIy not seen until the maIignancy is already far advanced. It is usuaIIy onIy in the advanced stages of carcinoma that definite symptoms are manifest, i.e., a bIoody vagina1 discharge and a history of hemorrhage on contact, such as that foIIowing vagina1 examination .or coitus. Pain is a Iate symptom and usuaIIy occurs after the cancer has aIready spread to the peritoneum and to the peIvic connective tissue which has a rich nerve suppIy. As a ruIe, few if any subjective symptoms are present during the earIy stage of this disease. There are probabIy two reasons why earIy carcinoma of the cervix is discovered late: (I) The patient is not IikeIy to seek medica advice unIess symptoms are present. (2) The examining physician may overlook early maIignancy or mistake it for a benign Iesion. The most certain way of diagnosing earIy carcinoma of the cervix is by biopsy. There are various accepted diagnostic procedures but none of them are compIeteIy satisfactory. The .positive SchiIIer test is not absoIute proof of maIignancy. According to Meyer, the correct diagnosis in 60 per cent of cases of carcinoma of the cervix would be missed by this test. MartzIoff points out that the overwheIming majority of unstained areas shows no histoIogica1 evidence of beginning cancer. SchiIIer, himself, states that his test is of no vaIue at a11 in differentiating uIcerating carcinoma and erosion, and suggests biopsy in cervical Iesions. In an experimenta check-up for cancer made by McFarIane, Fetterman and Sturgis on 1,000 supposedIy we11 women, thirty years of age and over, 4 malignancies of the uterus and 357 benign Iesions of the cervix were found by performing biopsies. Schmitz reports fifteen siIent carcinomas that were discovered accidentaIIy on histoIogica1 examination of cervical tissue following amputation of the cervix for extensive cervicitis, in a series of cases of primary carcinoma of the cervix observed between the years 1915 to 193 I. In a microscopic study of cervica1 tissue from 669 cervices, which did not show any signs of carcinoma on gross examination and were treated for chronic inflammatory lesions, Smith discovered sixteen carcinomas of the cervix (2.39 per cent) by routine microscopic examination of the removed tissue. Schmitz. reports a IOO per cent five-year cure in the above mentioned fifteen cases of siIent carcinoma which he discovered. This proves that onIy by earIy diagnosis and treatment the end resuIts of cancer
Deviations from the mendelian inheritance of retinitis pigmentosa

Retinitis pigmentosa (RP) is a heterogeneous group of hereditary disorders causing progressive retinal degeneration. Dominant, recessive, and X-linked forms are well established, but studies invariably reveal a high proportion of simplex cases inconsistent with the assumptions of simple monogenic inheritance. Segregation analysis of data ascertained in the RP National Survey showed that distribution of cases in families could be accounted for only by invoking assumptions of reduced penetrance and a proportion of sporadic cases.For proband sibships with normal parents, the hypothesis that all cases were recessive was rejected (X2 = 33.6), and the proportion of sporadic cases estimated to be 21%. RP and hearing loss are characteristic features of several monogenic syndromes, and even in the absence of a specific syndrome diagnosis, hearing impairment was the most commonly reported extraocular symptom in the survey, with 20.1% of probands having mild loss, and an additional 7.4% severe impairment. For the re...
Identification of Protein-Protein Interactions and Topologies in Living Cells with Chemical Cross-linking and Mass Spectrometry

We present results from a novel strategy that enables concurrent identification of protein-protein interactions and topologies in living cells without specific antibodies or genetic manipulations for immuno-/affinity purifications. The strategy consists of (i) a chemical cross-linking reaction: intact cell labeling with a novel class of chemical cross-linkers, protein interaction reporters (PIRs); (ii) two-stage mass spectrometric analysis: stage 1 identification of PIR-labeled proteins and construction of a restricted database by two-dimensional LC/MSMS and stage 2 analysis of PIR-labeled peptides by multiplexed LC/FTICR-MS; and (iii) data analysis: identification of cross-linked peptides and proteins of origin using accurate mass and other constraints. The primary advantage of the PIR approach and distinction from current technology is that protein interactions together with topologies are detected in native biological systems by stabilizing protein complexes with new covalent bonds while the proteins are present in the original cellular environment. Thus, weak or transient interactions or interactions that require properly folded, localized, or membrane-bound proteins can be labeled and identified through the PIR approach. This strategy was applied to Shewanella oneidensis bacterial cells, and initial studies resulted in identification of a set of protein-protein interactions and their contact/binding regions. Furthermore most identified interactions involved membrane proteins, suggesting that the PIR approach is particularly suited for studies of membrane protein-protein interactions, an area under-represented with current widely used approaches.
Clock Genes Show Circadian Rhythms in Salivary Glands

Circadian rhythms are endogenous self-sustained oscillations with 24-hour periods that regulate diverse physiological and metabolic processes through complex gene regulation by "clock" transcription factors. The oral cavity is bathed by saliva, and its amount and content are modified within regular daily intervals. The clock mechanisms that control salivary production remain unclear. Our objective was to evaluate the expression and periodicity of clock genes in salivary glands. Real-time quantitative RT-PCR, in situ hybridization, and immunohistochemistry were performed to show circadian mRNA and protein expression and localization of key clock genes (Bmal1, Clock, Per1, and Per2), ion and aqua channel genes (Ae2a, Car2, and Aqp5), and salivary gland markers. Clock gene mRNAs and clock proteins were found differentially expressed in the serous acini and duct cells of all major salivary glands. The expression levels of clock genes and Aqp5 showed regular oscillatory patterns under both light/dark and complete-dark conditions. Bmla1 overexpression resulted in increased Aqp5 expression levels. Analysis of our data suggests that salivary glands have a peripheral clock mechanism that functions both in normal light/dark conditions and in the absence of light. This finding may increase our understanding of the control mechanisms of salivary content and flow.
Computational and experimental study of a forced, timevarying, axisymmetric, laminar diffusion flame

Forced, time-varying flames are laminar systems that help bridge the gap between laminar and turbulent combustion. In this study, we investigate computationally and experimentally the structure of an acoustically forced, axisymmetric laminar methane-air diffusion flame, in which a cylindrical fuel jet is surrounded by a coflowing oxidizer jet. The flame is forced by imposing a sinusoidal modulation on the steady fuel flow rate. Rayleigh scattering and spontaneous Raman scattering of the fuel are used to generate the temperature profile. Particle image velocimetry (PIV) is used to measure the fuel tube exit velocity over a cycle of the forcing modulation. CH flame emission measurements have been done to predict the excitedstate CH (CH * ) levels. Computationally, we solve the transient equations for the conservation of total mass, momentum, energy, and species mass with detailed transport and finite-rate C 2 chemistry submodels to predict the pressure, velocity, temperature, and species concentrations as a function of the two independent spatial coordinates and time. The governing equations are written in primitive variables. Implicit finite differences are used to discretize the governing equations and the boundary conditions on a nonstaggered, noniumiform grid. Modified damped Newton's method nested with a Bi-CGSTAB iteration is utilized to solve the resulting system of equations. Results of the study include a detailed description of the fluid dynamic-thermochemical structure of the flame at a 20-Hz frequency. A comparison of experimentally determined and calculated temperature profiles and CH * levels agree well. Calculated mole fractions of species indicative of soot production (C 2 H 2 , CO) are compared against those levels in the corresponding steady flame and are observed to increase in peak concentration values and spatial extent. Analysis of acetylene production rates reveals additional significant production in the downstream region of the flame at certain times during the flame's cyclic history.
Is Smoking Delayed Smoking Averted

Antismoking efforts often target teenagers in the hope of producing a new generation of never smokers. Teenagers are more responsive to tobacco taxes than are adults. The author summarizes recent evidence suggesting that delaying smoking initiation among teenagers through higher taxes does not generate proportionate reductions in prevalence rates through adulthood. In consequence, the impact of taxes on smoking among youths overstates the potential long-term public health effects of this tobacco control strategy.
Assessing metadata utilization: an analysis of MARC content designation use

Metadata schemes emerge to meet community and user requirements, and they evolve over time to meet changing requirements. This paper reports results of an analysis of a large sample of MARC 21 bibliographic records. MARC 21 is an encoding scheme related closely to metadata elements occurring in library bibliographic records. The records were analyzed for the utilization of content designation available in MARC 21. Results indicate that less that 5% of available content designation accounts for over 80% of occurrences. The implications of these findings affect indexing policies, system design, and can inform setting requirements for extending a metadata scheme based on a threshold of community requirements.
Derivative of Gaussian functions as receptive field models for disparity sensitive neurons of the visual cortex

Non-symmetric Gabor functions are particularly useful neurophysiologic models of simple cell receptive fields which respond to disparity characteristics of visual stimuli. The left and right visual channels of these simple cell have receptive field profiles which are phase-shifted alterations of the same one-dimensional Gabor function. These profiles resemble derivative of Gaussian (DOG) functions, although DOG functions have never been evaluated using neurophysiologic data from disparity sensitive neurons. Here the authors demonstrate (a) the space frequency response characteristics of DOG functions as a model of a single receptive field, and (b) the space-frequency response characteristics of the combinations of two same-order DOG functions as a model of a simple cell disparity neuron which combine left and right receptive fields. Combining left and right visual fields in four different ways resulted in two characteristic patterns for both even and odd ordered derivatives. Each pattern appeared to be useful, in a different way, for detecting disparity information. These results suggest that DOG functions can be used to produce a set of equations for detecting disparity information.
State the Obvious

Before I begin my remarks to you this evening (Figure), I would like to take a just a moment to recognize and thank a very special group of first-time conference attendees … my family! Figure. R. Scott Ward, PT, PhD, APTA President. My wife, Diane, who is an accomplished scientist and an amazing life partner and mother, and my 3 remarkable daughters—Kristin, Sarah, and Mary—are truly the wind beneath my wings. It is their flexibility and gracious spirits that free me to serve and enable me to be effective on your behalf. I am grateful for them and so pleased they could be here in Boston with me for conference this year. Now, I invite you to take a short trip down memory lane with me to a time when I was a student physical therapist volunteering for a week at Muscular Dystrophy Association summer camp. It was a great experience to live with and assist a few young men with Duchenne muscular dystrophy for a week. I captured a glimpse of the effort and struggles associated with being a care provider for wonderful people with extraordinary needs. This perspective helped influence the way I looked at the material learned during my schooling. It was a perspective that was not obvious to me before that experience. I was allowed to attend daily medical clinics with the physical therapist, the neurologist, and the nurse. This firsthand experience with a medical team anchored my understanding that information and idea sharing are essential to maximize consumer care. The physical therapist allowed me to participate in his examinations, and we discussed treatment plans and goals. During one clinic, he asked me to express my conclusions from a gait assessment we had just completed, and I told him I was reluctant to do that because I …
Impact of effector cell differentiation on CD4+ T cells that evade negative selection by a self-peptide

We have used a transgenic mouse system to examine how differing reactivities of TCRs expressed by naive versus effector cells can shape the functional potential of autoreactive CD4+ T cells. Transgenic mice expressing TCRs that exhibit either high (TS1) or low [TS1(SW)] reactivity toward the I-Ed-restricted determinant S1 from the influenza virus PR8 hemagglutinin (HA) were mated with transgenic mice expressing HA under the control of different promoters. HACII mice express HA driven by an MHC class II promoter, and both the TS1 and TS1(SW) TCRs underwent substantial deletion in this background. HA104 mice express HA driven by an SV40 promoter, and the highly reactive TS1 TCR was substantially deleted. By contrast, the less reactive TS1(SW) TCR underwent little or no deletion in TS1(SW) x HA104 mice, although CD5 up-regulation indicated that they had interacted with the S1 self-peptide. In adoptive transfer studies, naive CD4+ T cells expressing the TS1(SW) TCR failed to proliferate in response to the S1 peptide in HA104 mice, and were inefficient at providing help for HA-specific antibody responses. However, effector CD4+ T cells generated from TS1(SW) x HA104 mice acquired the ability to proliferate in response to the S1 peptide in HA104 mice, and were as efficient as CD4+ T cells expressing the high reactivity TS1 TCR in helping HA-specific antibody responses. Collectively, these studies demonstrate a basis by which CD4+ T cells expressing TCRs with low reactivity toward self-peptides can evade negative selection and acquire enhanced autoreactivity following activation by a cross-reactive antigen.
Evaluation of plasma transport in a multipole ion source and its impact on discharge performance

Summary form only given. In this work, the current distribution at the four magnet rings of a cylindrical 16-cm diameter mild steel ion source discharge chamber was studied. The current distribution measurements were made using thin, electrically isolated collector electrodes affixed to each magnet ring. Current collected at the magnetic cusps as well as the intervening anode material was quantified as a function of discharge plasma conditions. Discharge efficiency and stability were investigated as a function of current distribution. This work is aimed at obtaining a more complete understanding of plasmas losses to the wall surfaces in multipole ion sources.
Synchronous rendezvous of very-low-range wireless agents

In this paper, we address the problem of temporal synchronization of a team of mobile agents on a set of rendezvous points defined by the nodes of a bipartite network. In particular, we assume very-low-range (VLR) wireless agents that travel along the edges of a bipartite network, and can only communicate with each other when they rendezvous at the nodes of the network. Temporal synchronization relies on distributed agreement protocols on the travel times and waiting times at the rendezvous points, and when integrated with the agents' motion, results in a hybrid multi-agent coordination scheme. We show that the resulting dynamic communication network is almost always eventually connected and, therefore, synchronous rendezvous of the agents on the nodes of the underlying path network is guaranteed. Unlike prior work on distributed agreement, where synchronization depends on communication, here dependence is both ways. Therefore, from a theoretical perspective our approach can be viewed as a way to jointly control communication and synchronization. We finally illustrate our approach in computer simulations.
A new nanonetwork architecture using flagellated bacteria and catalytic nanomotors

Molecular communication has been recently proposed for interconnected nano-scale devices as an alternative to classical communication paradigms such as electromagnetic waves, acoustic or optical communication. In this novel approach, the information is encoded as molecules that are transported between nano-scale devices within different distances. For short distances (nm-mm ranges) there exist molecular motors and calcium signaling techniques to realize the communication. For long distances (mm-m ranges), pheromones are used to transport information. In this work, the medium-range is explored to cover distances from ?m to mm and a molecular network architecture is proposed to realize the communication between nano-machines that can be deployed over different (short, medium and long) distances. In addition, two new communication techniques, flagellated bacteria and catalytic nanomotors, are proposed to cover the medium-range. Both techniques are based on the transport of DNA encoded information between emitters and receivers by means of a physical carrier. Finally, a qualitative comparison of both communication techniques is carried out and some future research topics are pointed out.
Sulfotransferase 1A1 Polymorphism, Endogenous Estrogen Exposure, Well-done Meat Intake, and Breast Cancer Risk

Sulfotransferase (SULT) 1A1 is involved in the inactivation of estrogens and bioactivation of heterocyclic amines and polycyclic aromatic hydrocarbons. A G→A transition at codon 213 ( CGC/Arg to CAC/His ) of the SULT1A1 gene was reported recently, and individuals homozygous for the His allele have a substantially lower activity of this enzyme than those with other genotypes. We hypothesized that the His allele may be a risk factor for breast cancer, particularly among women who had risk factors related to higher endogenous estrogen exposure. This hypothesis was investigated in a case-control study conducted in a cohort of postmenopausal Iowa women who completed a mailed questionnaire in 1986 on lifestyle factors including information on major breast cancer risk factors. DNA samples and information related to well-done meat intake were obtained from breast cancer cases diagnosed between 1992 and 1994 and a random sample of cancer-free cohort members. Multivariate analysis was performed on data from 156 cases and 332 controls who donated a blood sample. The frequency of the His allele was 41.6% in cases and 34.1% in controls ( P = 0.03), and the risk of breast cancer was increased with the number of His alleles ( P for trend = 0.02). Compared with women with the Arg/Arg genotype, an 80% elevated risk was observed among women homozygous for the His allele (95% confidence interval, 1.0–3.2; P = 0.04). This positive association was more pronounced among women who drank alcohol and had a high body mass index, early age at menarche, and late age at menopause, factors related to high endogenous estrogen exposure, than among those who did not have these risk factors. The risk of breast cancer was elevated with increasing doneness level of red meat intake among women with the Arg/Arg genotype ( P for trend, 0.01) or the Arg/His genotype ( P for trend, 0.10), whereas this association was not evident for women with the His/His genotype. The results from this study suggest that homozygosity for the SULT1A1 His 213 allele may be a risk factor for breast cancer, and its effect may be modified by the exposure level of endogenous estrogens and heterocyclic amines.
Clinical consequences of misinterpretations of neuroradiologic CT scans by on-call radiology residents.

BACKGROUND AND PURPOSE: Studies have looked at the accuracy of radiologic interpretations by radiology residents as compared with staff radiologists with regard to emergency room plain films, emergency room body CT scans, and trauma head CT scans; however, to our knowledge, no study has evaluated on-call resident interpretations of all types of neuroradiologic CT scans. Both as a part of our departmental quality control program and to address concerns of clinical services about misinterpretation of neuroradiologic CT scans by on-call radiology residents, we evaluated the frequency of incorrect preliminary interpretations of neuroradiologic CT scans by on-call radiology residents and the effect of such misinterpretations on clinical management and patient outcome. METHODS: As determined by the staff neuroradiologist the next day, all potentially clinically significant changes to preliminary reports of emergency neuroradiologic CT scans rendered by on-call radiology residents were recorded over a 9-month period. A panel of neuroradiologists reviewed and graded all the changed cases by consensus. An emergency department staff physician reviewed medical records of all submitted cases to determine clinical consequences of the misinterpretations. RESULTS: Significant misinterpretations were made in 21 (0.9%) of 2388 cases during the study period. There was a significant change in patient management in 12 of the cases, with a potentially serious change in patient outcome in two cases (0.08%). CONCLUSION: On-call radiology residents have a low rate of significant misinterpretations of neuroradiologic CT scans, and the potential to affect patient outcome is rare.
Self-improvement of learned action models with learned goal models

We introduce a new method for robots to further improve upon skills acquired through Learning from Demonstration. Previously, we have introduced a method to learn both an action model to execute the skill and a goal model to monitor the execution of the skill. In this paper we show how to use the learned goal models to improve the learned action models autonomously, without further user interaction. Trajectories are sampled from the action model and executed on the robot. The goal model then labels them as success or failure and the successful ones are used to update the action model. We introduce an adaptive sampling method to speed up convergence. We show through both simulation and real robot experiments that our method can fix a failed action model.
Ameritrade Holding Corporation

Synopsis: As Ameritrade, a discount internet-brokerage firm, prepares for a seasoned equity offering, many of its senior managers at are selling their stock in the company. The CEO is concerned that the market will interpret the sales as a signal that managers believe the firm to be overvalued, a signal that has the potential to interfere with the upcoming equity offering. Furthermore, he thinks that such sales have the potential to undermine a carefully thought-out compensation system designed to align the interests of managers with those of shareholders. Teaching Objectives: The case illustrates the difficulty faced by managers who have much of their wealth invested in the company's stock or options, and would like to sell some of those holdings. Can managers sell without harming the firms' other shareholders? This dilemma is a frequent one in entrepreneurially-based firms, and, with the wide adoption of stock and option-based compensation, it is increasingly common for managers in more established firms. The case specifically prompts students to consider the link between the firm's compensation system and managers' decision to sell their holdings in the firm. Why are managers selling? What are the effects of the sale on shareholder value? How does the compelled holding of the firm's stock affect its value to managers? The case is taught in Corporate Finance Management, a second-year elective MBA course. The case can also be used in an introductory corporate finance class, either within the context of market efficiency, insider trading or executive compensation systems (particularly emphasizing the cost of compensating managers in stock or options).
THE SHEAR STEESS OF SEA BREEZE ON A SWASH ZONE

Measurements of shear stress under the effect of a sea hreeze were made by simultaneous wind and temperature profiles over a shore near Fort Walton Beach, Florida It was found that the sea breeze In the surface boundary layer is in the atmospheric free-convection, regime The measured shear stress coefficient is in conformity with that obtained by other investigators by the sea surface tilt method under the unstable condition For coastal applications, the result is found to be more reliable than those assumed coefficients obtained under neutral stability for this localized coastal wind system.
Groin Pain Etiology: Hip-Referred Groin Pain

The orthopedic causes of groin pain are numerous and varied, and given the overlap with other medical specialties, it is often a diagnostic challenge. A clear organizational framework is necessary to determine the source as well as the pathological process responsible for groin pain. Pain may be related either to the bone or to the soft tissue surrounding it. These processes can be further divided into physiological or architectural problems in order to provide a diagnostic framework for its evaluation. This chapter discusses the relevant anatomy for this diagnostic workup and provides an outline describing the most common orthopedic causes of groin pain. More unusual conditions such as femoral acetabular impingement, labral tears, stress fractures, avascular necrosis, and transient osteoporosis are also covered. Groin-related symptoms are covered in the light of a possible orthopedic etiology. The physical examination is reviewed in detail in order to further differentiate these pathologies clinically. Recommendations for imaging and laboratory workup are explained in a stepwise and cost-effective fashion. This chapter will cover the treatment algorithms for these conditions and provide guidelines for appropriate referrals. The list, although not comprehensive, represents an excellent starting point for the orthopedic evaluation of groin pain.