cssi/SciSciGPT-SciSciNet huggingface dataset:
Unconstrained geometry complexes : Ethylene/α-olefin copolymerizations with a tetramethyldisilyl-bridged Cp-amido titanium complex

A new disilyl-bridged complex, [(N-tert-butylamido)(3-indenyl)tetramethyldisilyl]titanium dichloride (3), was synthesized and activated with methylaluminoxane (MAO) for propylene homopolymerization and ethylene/propylene and ethylene/1-hexene copolymerizations. A polypropylene with a slight isotactic enrichment was obtained. The number of regioerrors present in the polypropylene was somewhat smaller than that found in most polypropylenes made from monosilyl-bridged [(N-tert-butylamido)(3-indenyl)dimethylsilyl]titanium dichloride. The regioerrors detected in the copolymers obtained from 3/MAO were on the order of the amounts observed in polymers made with the monosilyl-bridged constrained geometry catalysts. Ethylene copolymers of propylene and 1-hexene had random sequence distributions and showed significant comonomer incorporation. Because of the presence of regioerrors, a modified method for determining the monomer composition and sequence distribution was developed from the direct measurement of the monomer content from the number of methylene and methine carbons per polymer chain, regardless of propylene inversion. An estimate of the error in the copolymerization reactivity ratio determination for regioirregular ethylene/α-olefin copolymers was obtained by the calculation of the reactivity ratios from monomer dyad sequences, with consideration given to the contribution of major regioirregular sequences. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3840–3851, 2005
Magnetic resonance imaging characteristics of glioblastoma multiforme: implications for understanding glioma ontogeny.

Glioblastoma multiforme (GBM), the most common malignant intracranial neoplasm in adults, carries a dismal prognosis. Gliomas can arise throughout the central nervous system but are always found in the subcortical white matter (SCWM). The notion of a “cancer stem cell” has gained increasing popularity, fueled by the recent discovery of cells with stemlike properties within human gliomas.1–5 Although the concept of cancer stem cells and the notion that gliomas may arise from stem or stemlike cells in the central nervous system are distinct, many studies have focused on neural stem cells in the subventricular zone (SVZ) as the “cell of origin” for all gliomas.6–8 There is growing evidence that glial progenitors that are abundant and widely distributed throughout the brain also have the capacity to form gliomas.9–15 However, recent articles still support the hypothesis that neural stem cells/progenitors in the SVZ are uniquely capable of forming glioblastomas,16–18 some suggesting that even tumors distant from the SVZ may arise there19,20 and that the SVZ should be therapeutically targeted in patients with GBM to prevent recurrence.21 In view of these conflicting viewpoints, we reviewed radiological evidence in GBM patients to provide insight into this question of glioma ontogeny. To understand the implications on glioma ontogeny in a study of GBMs on preoperative magnetic resonance imaging (MRI), 3 assumptions were made. The first assumption was that the cells that give rise to tumors are potentially distributed widely throughout the brain. The second assumption was that tumors begin as a point of origin and grow by radial dispersion into the surrounding brain tissue. The final assumption was that the patterns of dispersion would depend on the geometry of the tissue boundaries, including the gray white junctions and the pial and ventricular margins. From these assumptions, 3 predictions were made regarding the patterns likely to be observed. First, tumors originating at points in the white matter distant from the SVZ might approach or abut the SVZ as they grow. Therefore, the distance from the ventricle to the nearest edge of the tumor would negatively correlate with tumor volume. Second, for tumors that arise in the white matter, the distances between the tumor center and the ventricle should not show a clear relationship to tumor volume because the center of the tumor should remain relatively static as the tumor grows radially. Third, in tumors that originate at the SVZ, the distance between the center of the tumor and the ventricle should increase as the tumor increases in size because, as the radial growth of the tumor is constrained by the ventricle in one direction, the center will be displaced away from the ventricle as the tumor grows.
URBANNESS AND UNCONVENTIONAL BEHAVIOR: A PARTIAL TEST OF CLAUDE FISCHER'S SUBCULTURAL THEORY

Eleven hypotheses concerning individual behavior are derived from Claude Fischer's ecological subcultural theory linking size-of-place, subcultural development, and unconventional behavior. Data from a three-state survey are used to test the derived hypotheses. The findings are mixed, which suggests the theory has merit but that it is too general and should be refined to specify the conditions under which various effects are most likely. The results suggest that a refinement must confront the following realities: (1) the size of the population is not necessarily predictive of high probabilities of all kinds of deviance, (2) all deviance is not subculturally linked, and (3) subcultures and subcultural involvement are not necessarily concentrated in larger places. Nevertheless, (4) when subcultural involvement is strong, it exercises great influence on behavior. Approaches for refining the theory are suggested.
Usefulness of carcinoembryonic antigen monitoring despite normal preoperative values in node-positive colon cancer patients.

PURPOSE: The aim of our study was to determine to what extent serial carcinoembryonic antigen (CEA) monitoring is helpful in detecting colorectal cancer recurrence in patients if their preoperative serum CEA is normal. Additional major objectives of this study were to correlate CEA immunohistochemical features of the primary tumor with serum CEA levels at the time of tumor recurrence in node-positive colorectal cancer patients with low preoperative CEA values. METHODS: One hundred fourteen node-positive colorectal cancer patients with preoperative serum CEA levels of <5.0 ng/ml undergoing clinically curative operations were studied. Primary tumors were evaluated for tissue CEA using the same monoclonal antibody as used for serum CEA determinations utilizing the avidin-biotin-peroxidase immunohistochemical technique. RESULTS: The exact preoperative serum CEA value did not correlate with tumor grade, immunohistochemical CEA intensity or pattern. In the 32 patients who developed recurrent cancer, the serum CEA at recurrence was greater than 5 ng/ml in 44 percent. All such patients had CEA present in their primary tumor. There was no correlation with the exact preoperative serum CEA, the intensity of the primary tissue CEA, or the localization of such CEA and subsequent serum elevation at recurrence. CONCLUSION: Serum CEA is a useful marker in the detection of recurrent colorectal cancer despite normal preoperative values.
Image segmentation using consensus from hierarchical segmentation ensembles

Unsupervised, automatic image segmentation without contextual knowledge, or user intervention is a challenging problem. The key to robust segmentation is an appropriate selection of local features and metrics. However, a single aggregation of the local features using a greedy merging order often results in incorrect segmentation. This paper presents an unsupervised approach, which uses the consensus inferred from hierarchical segmentation ensembles, for partitioning images into foreground and background regions. By exploring an expanded set of possible aggregations of the local features, the proposed method generates meaningful segmentations that are not often revealed when only the optimal hierarchy is considered. A graph cuts-based approach is employed to combine the consensus along with a foreground-background model estimate, obtained using the ensemble, for effective segmentation. Experiments with a standard dataset show promising results when compared to several existing methods including the state-of-the-art weak supervised techniques that use co-segmentation.
Rehabilitation and the long-term outcomes of persons with trauma-related amputations

Abstract Pezzin LE, Dillingham TR, MacKenzie EJ. Rehabilitation and the long-term outcomes of persons with trauma-related amputations. Arch Phys Med Rehabil 2000;81:292-300. Objective: To examine the long-term outcomes of persons undergoing trauma-related amputations, and to explore factors affecting their physical, social, and mental health and the role of inpatient rehabilitation in improving such outcomes. Design: Abstracted medical records and interview data sought for a retrospective cohort of persons who had undergone a lower-limb trauma-related amputation. Participants: Patients identified with a principal or secondary diagnosis of a trauma-related amputation to the lower extremity at the University of Maryland Shock Trauma Center between 1984 and 1994. Patients with spinal cord injury or traumatic brain injury were excluded. Results: Of 146 patients who had trauma-related amputations to the lower limb at the University of Maryland Shock Trauma Center during the study period, nearly 9% died during the acute admission and 3.5% died after discharge. About 87% of all trauma-related amputations involved males, and roughly three quarters involved white persons. About 80% of all amputations occurred before age 40. The health profile of traumatic amputee subjects interviewed in the study ( n = 78, 68% response rate) was systematically lower than that of the general US population for all SF-36 scores. The differences in profiles were largest among SF-36 scales sensitive to differences in physical health status, particularly physical functioning, role limitations due to physical health, and bodily pain. About one fourth of persons with a trauma-related amputation reported ongoing severe problems with the residual limb, including phantom pain, wounds, and sores. The number of inpatient rehabilitation nights significantly improved the ability of patients with amputation to function in their physical roles, increased vitality, and reduced bodily pain. Inpatient rehabilitation was also significantly correlated with improved vocational outcomes. Conclusions: These findings suggest a substantial effect of inpatient rehabilitation in improving long-term outcomes of persons with trauma-related amputations. © 2000 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation
Chronic clonidine treatment produces desensitisation of post but not presynaptic α2-adrenoceptors

Rats were treated chronically with clonidine by osmotic minipump (500 micrograms/kg daily for 14 days). One day after the end of the infusion period, the animals were pithed, and alpha 2-presynaptic and -postsynaptic adrenoceptor responses evaluated using inhibition of cardioaccelerator response to sympathetic stimulation by guanabenz, and pressor response to guanabenz respectively. Chronic clonidine treatment had no effect on the presynaptic effect of guanabenz, but the postsynaptic response to this agonist was decreased. In a separate group of pithed rats treated chronically with clonidine, there was no alteration in the increment in plasma noradrenaline concentration produced by sympathetic stimulation, and no alteration in the yohimbine-induced enhancement of plasma noradrenaline response to sympathetic stimulation. These data argue against desensitisation of peripheral presynaptic alpha 2-adrenoceptors by chronic administration of alpha 2-adrenoceptor agonist. Sympathetic hyperactivity following withdrawal of chronic clonidine treatment may be mediated by down-regulation of postsynaptic alpha 2-adrenoceptors in the CNS.
Relation of the ankle brachial index to left ventricular ejection fraction.

Low and high ankle brachial index (ABI) values are both a marker of peripheral arterial disease and associated with greater cardiovascular disease event rates. The objective of the present study was to determine whether the ABI is associated with left ventricular (LV) systolic function. We studied 175 patients (age 67 ± 13 years, 58% men) referred for ABI determination who had had the LV ejection fraction (EF) determined using echocardiography within 14 days. The mean LVEF was 47 ± 13%, mean ABI for the right leg was 0.93 ± 0.32, and the mean ABI for the left leg was 0.94 ± 0.26. Of the 175 patients, 91 (52%) had a low, 69 (39%) had a normal, and 15 (9%) had a high ABI. The mean LVEF increased in a stepwise manner from the low, to normal, to abnormally high ABI groups (43 ± 13% vs 51 ± 12% vs 57 ± 5%, respectively; p
Relativistic invariance of the external interaction of a composite system of charged particles with the quantized radiation field

Abstract We show how the usual Foldy-Wouthuysen reduced and additive expression for the external electromagnetic interaction of a composite system of two charged particles should be modified so that it leads to relativistically correct results to relative order 1/ c 2 .
The association of body fat distribution with hypertension, hypertensive heart disease, coronary heart disease, diabetes and cardiovascular risk factors in men and women aged 18–79 years

To confirm the reported association of body fat distribution with cardiovascular disease, diabetes, blood pressure and serum cholesterol, data from the 1960-62 Health Examination Survey were analyzed. In this sample drawn from the noninstitutionalized population of the United States aged 18-79, mean values of two indices of upper versus lower body fat distribution increased steadily with age. Men had higher values than women, and black women had higher values than white women. Higher values of the indices were significantly associated with higher blood pressure, post-load serum glucose and greater prevalence of definite hypertension and definite hypertensive heart disease independent of multiple confounders. Associations with higher serum cholesterol and definite coronary heart disease prevalence were independent of overall ponderosity but not of age and multiple other confounders. Greater abdominal relative to lower body fat deposits were independently associated with increased cardiovascular risk in men and women, blacks and whites.
Wall Climbing Robot Using Electrostatic Adhesion Force Generated by Flexible Interdigital Electrodes

Electrostatic adhesion technology has broad application prospects on wall climbing robots because of its unique characteristics compared with other types of adhesion technologies. A double tracked ...
Chandra ACIS Subpixel Event Repositioning: Further Refinements and Comparison between Backside- and Frontside-illuminated X-Ray CCDs

We further investigate subpixel event repositioning (SER) algorithms in application to Chandra X-Ray Observatory (Chandra) CCD imaging. SER algorithms have been applied to backside-illuminated (BI) Advanced CCD Imaging Spectrometer (ACIS) devices and demonstrate spatial resolution improvements in Chandra ACIS observations. Here a new SER algorithm that is charge split-dependent is added to the SER family. We describe the application of SER algorithms to frontside-illuminated (FI) ACIS devices. The results of SER for FI CCDs are compared with those obtained from SER techniques applied to BI CCD event data. Both simulated data and Chandra ACIS observations of the Orion Nebular Cluster were used to test and evaluate the achievement of the various SER techniques.
Benzothiophene Selective Estrogen Receptor Modulators Provide Neuroprotection by a Novel GPR30-Dependent Mechanism

The clinical benzothiophene SERM (BT-SERM) raloxifene was compared with estrogens in protection of primary rat neurons against oxygen-glucose deprivation (OGD). Structure−activity relationships for neuroprotection were determined for a family of BT-SERMs displaying a spectrum of ERα and ERβ binding affinity and agonist/antagonist activity, leading to discovery of a neuroprotective pharmacophore, present in the clinically relevant SERMS, raloxifene, and desmethylarzoxifene (DMA), for which submicromolar potency was observed for neuroprotection. BT-SERM neuroprotection did not correlate with binding to ER or classical ER activity; however, both the neuroprotective SERMs and estrogens were shown, using pharmacological probes, to activate the same kinase signaling cascades. The antiestrogen ICI 182,780 inhibited the actions of estrogens but not those of BT-SERMs, whereas antagonism of the G-protein coupled receptor, GPR30, was effective for both SERMs and estrogens. Since SERMs have antioxidant activity, ER-i...
Time series models of mortgage choice: Evidence of lender influence

Unit root, co-integration, and Granger Causality are used to test specification of a generalized time series model of mortgage choice. Unit root tests determine that both the fixed-adjustable spread (FAsp) and the proportion of ARM originations (AP) are first difference stationary. The cointegrating vector between FAsp and AP was found to be weak, raising questions regarding their “long-term relationship.” Causality tests determined that ARM originations Granger causes the fixed-adjustable mortgage spread (AP→FAsp) rather than FAsp→AP. This result suggests that mortgage originators adjust the current FAsp spread based on last periods allocation. The coefficient vector for this specification was unstable and became increasingly negative during the 1980s.
Nuclear data sheets for A = 86

Experimental data on the nuclear level structure of mass 86 nuclei are compiled, and adopted level properties and decay schemes are presented. The most extensively investigated nuclei are {sup 86}Rb and {sup 86}Sr, for which the energies of many excited states have been accurately measured from radioactive decay studies and from nuclear reactions. The properties of most of these states have not, as yet, been well determined although the data greatly narrow the range of possible spin assignments for many of them. There remain several unresolved discrepancies in the 86Rb thermal neutron capture data and uncertainty as to the placement of many of the reported gammas. The low-lying states in {sup 86}Y have also been well studied via the decay of {sup 86}mY and {sup 86}Zr, and spin and parity assignments have been made to all the known levels. However, these decays excite levels up to only 0.883 MeV. The levels in {sup 86}Kr have been studied through the decay of {sup 86}Br and through inelastic deuteron scattering, and 10 excited states have been reported up to 6.7 MeV. Unfortunately, spin and parity assignments are available only for the first-excited state at 1.56 MeV. For the remaining members of themore » A-chain, {sup 86}Se, {sup 86}Br, and {sup 86}Zr, only the ground-state decay properties have been studied.The adopted level properties are based on data available through July 1970. Data from several later references on {sup 86}Br decay, {sup 86}Rb, and {sup 86}Sr which were added in proof were not included in the adopted level properties.« less
Attitudes of obstetrician-gynecologists toward DNA testing for a genetic susceptibility to breast cancer

Objective : To assess knowledge and attitudes of area obstetrician-gynecologists toward DNA testing for genetic susceptibility to breast cancer. Methods : At a staff meeting of each of the Rochester area's hospitals that had an obstetric service, we assessed knowledge of inherited predisposition to breast cancer, presented the current status of testing for genetic susceptibility, and assessed attitudes toward such testing. Results : The majority of the physicians surveyed believed that current BRCA1 testing can detect a genetic predisposition to breast cancer accurately enough to be clinically useful (81%) and that a young woman with a family history of breast cancer not currently having regular mammography is likely to benefit from DNA testing because a positive result may motivate her to start mammography earlier (88%). However, most respondents thought that women who test positive are likely to be excessively anxious (87%) and may be discriminated against for insurance purposes (75%). In response to an invitation to participate in a clinical trial of free BRCA1 screening, 74 (70%) desired to participate. Conclusion : Obstetrician-gynecologists expect women detected to have a BRCA1 mutation to be motivated to conduct surveillance, but also to experience anxiety and possible discrimination.
Tactical Uses of Stories: Participation Frameworks within Girls' and Boys' Disputes.

This paper investigates how children use stories as tools for arranging and rearranging social organization. I examine how boys and girls, in their same‐sex groups, use features of stories to accomplish and restructure social identities within encounters. Though girls and boys make use of similar resources, they construct quite different types of events. Boys use stories to continue an ongoing argument while reshaping the domain of dispute. Girls, by way of contrast, use stories to restructure alignments of participants, not only in the current interaction, but also at some future time. For example, a story can depict an absent party talking about a current addressee behind her back. By organizing her story in this way, a teller can elicit from her recipient a promise to confront the offender. Such “he‐said‐she‐said” confrontations constitute a major domain of political action for the girls’ group, and an upcoming confrontation can mobilize the entire neighborhood. This study is based on fieldwork with a ...
During EPO or anemia challenge, erythroid progenitor cells transit through a selectively expandable proerythroblast pool.

Investigations of bone marrow (BM) erythroblast development are important for clinical concerns but are hindered by progenitor cell and tissue availability. We therefore sought to more specifically define dynamics, and key regulators, of the formation of developing BM erythroid cell cohorts. A unique Kit−CD71highTer119− “stage E2” proerythroblast pool first is described, which (unlike its Kit+ “stage E1” progenitors, or maturing Ter119+ “stage E3” progeny) proved to selectively expand ∼ 7-fold on erythropoietin challenge. During short-term BM transplantation, stage E2 proerythroblasts additionally proved to be a predominantly expanded progenitor pool within spleen. This E1→E2→E3 erythroid series reproducibly formed ex vivo, enabling further characterizations. Expansion, in part, involved E1 cell hyperproliferation together with rapid E2 conversion plus E2 stage restricted BCL2 expression. Possible erythropoietin/erythropoietin receptor proerythroblast stage specific events were further investigated in mice expressing minimal erythropoietin receptor alleles. For a hypomorphic erythropoietin receptor-HM allele, major defects in erythroblast development occurred selectively at stage E2. In addition, stage E2 cells proved to interact productively with primary BM stromal cells in ways that enhanced both survival and late-stage development. Overall, findings reveal a novel transitional proerythroblast compartment that deploys unique expansion devices.
Technological Resistance: A Metaphor Analysis of Enron E-Mail Messages

This project provides an example of employees “talking back,” or resisting dominant management rhetoric, via e-mail at the now defunct Enron Corporation. Situated within the study of organizational rhetoric, this article examines metaphors in e-mail messages at Enron, and how those metaphors supported certain discursive value systems that helped create and maintain the company's oppressive internal culture, but also how the use of different metaphors supported alternative discourses that could have possibly led to a different kind of organization. As Morgan (2006) argued, metaphors offer new ways of thinking and seeing. And, as Burke (1945) suggested, metaphors have the power to transform dominant discursive systems.
The Stabilizing Effect of the ERM on Exchange Rates and Interest Rates: Some Nonparametric Tests

This paper uses nonparametric procedures to test for a shift in the volatility of nominal and real exchange rates for members and nonmembers of the ERM. The results imply a reduction in volatility for ERM members, especially during the latter half of its operation. We also demonstrate that this enhanced stability was not bought at the expense of increased interest rate volatility. The issue of interest rate volatility during the British pound's participation in the ERM is also examined.
Testing the Feasibility of a DVD-based intervention to promote preparedness for mammography in women with intellectual disabilities

Women with intellectual disabilities (ID, formerly mental retardation) have a similar breast cancer incidence as the general population, but they have higher breast cancer mortality and lower rates of regular screening mammography. We conducted a feasibility study evaluating acceptability, demand, and limited efficacy of a health education DVD about mammography for women with ID. The DVD was developed in order to address disability-specific barriers to mammography identified in prior studies, such as anxiety related to navigating the logistics of obtaining a mammogram. The DVD was found to be acceptable and feasible, and led to a moderate increase in mammography preparedness in this population. Study results suggest that this DVD-based intervention is an appropriate candidate for further study measuring efficacy and effectiveness in increasing regular mammography in women with ID, a disparity population.
Fatigue performance of production-quality aircraft fastener holes

A two part study was conducted on the effects of hole drilling on the fatigue life of aircraft rivet holes in 2024-T3 aircraft quality aluminum. The first part of the study determined the drilling parameters that had the greatest effect on hole quality. In this, the second part of the study, the fatigue lives resulting from these drilling parameters are compared. It was found that machining marks play a greater role than residual stress in the fatigue life of production-quality holes. Machine drilling greatly reduces machining marks, increasing fatigue life by almost a factor of three. Dull bits appear to increase residual stress, but also increase machining marks, resulting in an approximately equal overall fatigue life.
Extended functionalized of the fluted [4]peristylane perimeter

Abstract Syntheses of [4]peristylane-2,4,6-trione (11) and 2,4,6,8-tetraone (17) are described. In 17, all four of the methylene carbons present in the parent [4]peristylane ring system are seen to be oxidized. The C 4v symmetry of the tetraketone is reflected in its physical and spectral properties.
Non-adiabatic atomic coherence at work in the oxygen laser source for atmospheric remote sensing

We pump ambient air by loosely-focused ultraviolet pulses and generate a backward laser-like beam for use in remote sensing. We find that this efficient emission is likely linked to non-adiabatic coherence effects in atomic oxygen.
Intermediates in guanidine-HCl unfolding of glutamine synthetase from the extreme thermophile, Bacillus caldolyticus

Abstract Glutamine synthetase is expressed in Bacillus caldolyticus as two isoforms that differ in physico-chemical and regulatory properties. Biphasic kinetics of thermal denaturation of E-I and E-II (Merkler, D.J., et al. (1987) Biochemistry 26, 7805), suggested the formation of intermediates. CD spectral changes of E-II induced by guannidine-HCL clearly inndcate a three-state pathway for unfolding (N→I→D). Refolding of E-II from 6 M GuHCl led to only 15% recovery of activity, compared to ⩾ 90% with E-I.
Motivational determinants in the performance of retarded children.

A number of studies are discussed indicating that many of the behavioral differences between familial retardates and normal children of the same MA are a result of differences in the motivational systems of the two types of children rather than being due to the intellectual factor alone.
Social and Environmental Predictors of Adjustment in Homeless Children

(1997). Social and Environmental Predictors of Adjustment in Homeless Children. Journal of Prevention & Intervention in the Community: Vol. 15, No. 2, pp. 1-17.
Stability of the inverted pendulum subjected to almost periodic and stochastic base motion—An application of the method of averaging

Abstract The stability of the inverted pendulum is re-examined using the method of averaging. The stability boundaries are determined for small amplitude, high frequency, sinusoidal and almost periodic base motions. It is shown for an almost periodic base motion that the solutions on the stability boundaries can be approximated by specific Mathieu functions. The method of averaging leads to the discovery by analog computer simulation that the pendulum can be stabilized in the inverted position with a base motion that is a sample function from a stochastic process with a continuous power spectral density function.
Sex differences in the effects of ethanol pre-exposure during adolescence on ethanol-induced conditioned taste aversion in adult rats

Alcohol use, which typically begins during adolescence and differs between males and females, is influenced by both the rewarding and aversive properties of the drug. One way adolescent alcohol use may modulate later consumption is by reducing alcohol s aversive properties. Here, we used a conditioned taste aversion (CTA) paradigm to determine if pre-exposure to alcohol (ethanol) during adolescence would attenuate ethanol-induced CTA assessed in adulthood in a sex-dependent manner. Male and female Long-Evans rats were given intraperitoneal (i.p.) injections of saline or 3.0 g/kg ethanol in a binge-like pattern during postnatal days (PD) 35–45. In adulthood (> PD 100), rats were given access to 0.1% saccharin, followed by saline or ethanol (1.0 or 1.5 g/kg, i.p.), over four conditioning sessions. We found sex differences in ethanol-induced CTA, with males developing a more robust aversion earlier in conditioning. Sex differences in the effects of pre-exposure were also evident: males, but not females, showed an attenuated CTA in adulthood following ethanol pre-exposure, which occurred approximately nine weeks earlier. Taken together, these findings indicate that males are more sensitive to the aversive properties of ethanol than females. In addition, the ability of pre-exposure to the ethanol US to attenuate CTA is enhanced in males compared to females.
Ternary gas diffusion - in vitro studies.

Abstract The purpose of these experiments was to compare diffusive gas movement in a two-gas system with that in a three-gas system. Gas mixtures of different compositions were placed initially on either side of a removable partition dividing a cylindrical lucite diffusion chamber, filled with 3 mm glass beads. This served to slow diffusion, minimize convective currents generated by removing the partition, and stabilize temperature within the chamber. In two-gas systems, after the partition was removed, oxygen equilibrated between the two parts of the chamber more rapidly in a helium environment than in a nitrogen environment, conforming with predictions based on binary gas laws. Results obtained with a three-gas system differed significantly from those obtained with the binary system. With 21% oxygen in helium initially in one half of the chamber and 21% oxygen in nitrogen in the other, p o 2 rose transiently in the He-O 2 side of the chamber. Qualitatively, similar results were obtained when the O 2 N 2 mixture was replaced by 100% nitrogen. Pressure in the system remained essentially constant. The possible mechanisms responsible for the p o 2 rise were studied using a computer model of the system. This showed that movement of a given gas may be affected significantly by movement of other gases in the system. Hence, application of binary gas diffusion laws to systems containing more than two gases may lead to significant errors.
Innovative long period gratings: principles and applications

In this paper, some recent advances in long period gratings, including (1) widely tunable single resonant band long period gratings, (2) long period gratings fabricated in single crystal sapphire fibers, and (3) long period gratings fabricated in photonic crystal fibers are presented. The applications of these novel long period grating to next generation ultra high capacity optics communication networks, high temperature distributed fiber optic sensors, and highly sensitive biosensors are discussed. Quantitative analyses and preliminary experimental results are provided.
Work in progress - Engineering ethics in a design paradigm

Many engineering students may feel that ethics is ambiguous and subjective, and that studying ethics is not a good use of their time. Ethics is indeed far from the cut and dry precision of their technical coursework, but it is hardly without structure or rigor. To bridge the perceived gap between engineering and ethics, we felt that the abstract aspects of engineering and the concrete aspects of ethics should be brought closer together. One such area of engineering, in which students already have explicit training dealing with ambiguous non-quantitative problems, is design. We have therefore attempted to model an approach to engineering ethics on the principles of engineering design. The ethical problem is analogized as a design problem, with the principles of the Belmont report as the design goals. We are assessing this approach by employing a pre- and post survey of ethical attitudes, and a pre- and post essay response to an ethical case.
Image coding using wavelet transform and classified vector quantisation

The wavelet transform, which provides a multiresolution representation of images, has been widely used in image compression. A new image coding scheme using the wavelet transform and classified vector quantisation is presented. The input image is first decomposed into a hierarchy of three layers containing ten subimages by the discrete wavelet transform. The lowest resolution low frequency subimage is scalar quantised with 8 bits/pixel. The high frequency subimages are compressed by classified vector quantisation to utilise the crosscorrelation among different resolutions while reducing the edge distortion and computational complexity. Vectors are constructed by combining the corresponding wavelet coefficients of different resolutions in the same orientation and classified according to the magnitude and the position of wavelet transform coefficients. Simulation results show that the proposed scheme has a better performance than those utilising current scalar or vector quantisation schemes.
Biological nutrient removal in three‐stage suspended growth reactor system

Eutrophication of receiving waters due to the discharge of nitrogen and phosphorus in the wastewater effluent has received great concern in the United States. As a result, many techniques have been proposed and aimed at the modification of the conventional activated sludge process to improve nutrient removal. A research program was conducted for comparative performance evaluation of conventional, anoxic‐aerobic, and anoxic‐anaerobic‐aerobic treatment sequences for nitrogen and phosphorus removal. The results indicated that BOD, and TSS, nitrogen and phosphorus removals in anoxic‐anaerobic‐aerobic treatment sequence were better than those for anoxic‐aerobic treatment sequence. Both process trains however, performed significantly better than conventional activated sludge. The three‐stage biological grlowth reactor has a great potential for upgrading existing activated sludge plant.
Cloud-radiative forcing and climate: results from the Earth radiation budget experiment.

The spaceborne Earth Radiation Budget Experiment was begun in 1984 to obtain quantitative estimates of the global distributions of cloud-radiative forcing. The magnitude of the observed net cloud forcing is about four times greater than the expected value of radiative forcing from a doubling of CO2; the shortwave and longwave components of cloud forcing are about 10 times as large as those for a CO2 doubling. Small changes in the cloud-radiative forcing fields can therefore play a significant role as a climate-feedback mechanism.
An estimator of relative potency

The Kolmogorov-Sxnirnov statistic is used as a basis for defining nonparaim trie point and interval estimators for the relative potency of a test preparation with respect to a standard preparation These estimators compare favorably with those proposed by Sen (1963) if the dosage distribuiton has heavy mass in either of its tails.
Predictive value of surveillance cultures for systemic infection due to Candida species.

Weekly fungal surveillance cultures (1,542 cultures) of urine (475), stool (520) and oropharyngeal (547) specimens from 111 patients on the bone marrow transplant and hematologic malignancy services were analyzed. Forty-three percent of the patients were colonized by Candida albicans and 10.8 % by Candida tropicalis. There were 22 proven systemic fungal infections, ten due to Candida albicans,eight to Candida tropicalis,one each to Candida pseudotropicalis and Torulopsis glabrata,and two to Aspergillus species. Positive surveillance cultures for Candida tropicalis were highly predictive of systemic infection. The finding of two or more positive cultures yielded high positive predictive values (100%) as a function of body site. Positive surveillance cultures for Candida albicans were not predictive of disease but negative cultures for Candida albicans and Candida tropicalis had a high negative predictive value (95–99 %). Surveillance culture data for specific Candida species may aid in diagnostic and therapeutic decision making.
The mechanisms of vision loss associated with a cotton wool spot

We characterized the perceptual, functional, and structural abnormalities associated with retinal ischemia during a cotton wool spot episode and its sequelae. The border of the visually salient field anomaly mirrored the quantitatively measured relative scotoma. Results of resolution perimetry and high resolution imaging indicated that there was a substantial loss of retinal ganglion cells within the affected region. A disruption in retinal nerve fiber arrangement was found at the cotton wool spot and within the arcuate relative scotoma. The presence of the arcuate relative scotoma is consistent with the hypothesis of failed signal transmission along the axons that pass through the cotton wool spot. The different levels of loss associated with the arcuate and focal scotomas indicate different underlying pathologies.
An optimized reconfigurable power spectral density converter for real-time shrew DDoS attacks detection

The shrew DDoS attacks are stealth low-rate TCP-targeted DDoS attacks, which conceal their malicious activities into normal traffic. Although the good pretense eludes them from being detected in time domain, the existent energy exposes them in frequency domain. Online Power Spectral Density (PSD) analysis necessitates real-time PSD data conversion is a must. In this paper, an optimized FPGA based real-time PSD converter is proposed, which is based on our innovative component-reusable Auto-Correlation (AC) algorithm and the adapted 2N-point real-valued Discrete Fourier Transform (DFT) algorithm. Further optimization is achieved through the exploration of algorithm characters and hardware parallelism for this case. The evaluation results from both simulation and synthesis are provided. The conversion of a 512-point data sequence can be finished in the time interval of sampling one data point; and the overall design could be easily fitted in a Xilinx Virtex2 Pro FGPA.
The role of uncertainty analysis in treatment planning

The role of uncertainty analysis in 3-D treatment planning systems was addressed by four institutions which contracted with NCI to evaluate high energy photon external beam treatment planning. Treatment plans were developed at eight disease sites and the effects of uncertainties assessed in a number of experiments. Uncertainties which are patient-site specific included variations in the delineation of target volumes and normal tissues and the effects of positional uncertainties due to physiological motion and setup nonreproducibility. These were found to have a potentially major impact on the doses to the target volumes and to critical normal tissues which could result in significantly altered probabilities of tumor control and normal tissue complications. Other uncertainties, such as the conversion of CT data to electron densities, heterogeneities and dose calculation algorithms' weaknesses, are related to physical processes. The latter was noted to have the greatest potential contribution to uncertainty in some sites. A third category of uncertainty related to the treatment machine, the consequences of compensator misregistration, are exclusive to the site and the treatment portal. Because conventional treatment planning systems have not incorporated uncertainty analysis, tools and techniques had to be devised for this work; further development in this area is needed. Many of the analyses could not have been done without full 3-D capabilities of the planning systems, and it can be anticipated that the availability of uncertainty analysis in these systems which allow nontraditional beam arrangements will be of great value.
Collective response of zebrafish shoals to a free-swimming robotic fish.

In this work, we explore the feasibility of regulating the collective behavior of zebrafish with a free-swimming robotic fish. The visual cues elicited by the robot are inspired by salient features of attraction in zebrafish and include enhanced coloration, aspect ratio of a fertile female, and carangiform/subcarangiform locomotion. The robot is autonomously controlled with an online multi-target tracking system and swims in circular trajectories in the presence of groups of zebrafish. We investigate the collective response of zebrafish to changes in robot speed, achieved by varying its tail-beat frequency. Our results show that the speed of the robot is a determinant of group cohesion, quantified through zebrafish nearest-neighbor distance, which increases with the speed of the robot until it reaches . We also find that the presence of the robot causes a significant decrease in the group speed, which is not accompanied by an increase in the freezing response of the subjects. Findings of this study are expected to inform the design of experimental protocols that leverage the use of robots to study the zebrafish animal model.
Experimental aspects of Fourier transform Raman spectroscopy

Using a commercial Fourier transform infrared spectrometer and the 1.064μm line of a CW Nd∶YAG laser, we have measured the Raman spectra of a wide variety of materials. The Raman scattered light, Stokes shifted toward the mid-infrared, is collected, using a 90° lens geometry, and focused through the emission port of the spectrometer. After passing through the Michelson interferometer, the light is detected by a thermoelectrically-cooled high-sensitivity germanium detector. The Fourier transform of the resulting interferogram gives the Raman spectrum. This new technique allows spectra to be obtained of samples which were previously completely masked by competing fluorescence. In addition, FT-Raman also allows moieties, such as hydrocarbon chains, which are not present in resonance enhanced spectra, to be investigated. We will discuss our approach toward FT-Raman, which is compatible with traditional Raman spectroscopy, present representative spectra of liquids and solids, and draw some comparisons and contrasts between dispersive and FT measurements.
The role of T lymphocytes in the pathogenesis of asthma

There is considerable evidence to support a role for T cells in asthma, particularly the involvement of T(H)2 cells both in atopic allergic asthma and in nonatopic and occupational asthma. There might also be a minor contribution from T(C)2 CD8+ T cells. Several T(H)2 cytokines have the potential to modulate airway inflammation, particularly IL-13, which induces airway hyperresponsiveness independently of IgE and eosinophilia in animal models. The identification of transcription factors controlling T(H)1 and T(H)2 development further support the T(H)2 hypothesis because GATA3 is overexpressed and T-bet is underexpressed in the asthmatic airway. Specific T cell directed immunotherapy might allow induction, modulation, or both of T-cell responses, and elucidation of the mechanisms of regulatory T cells might allow further optimization of immunotherapy. Recent advances in our understanding of dendritic cell function in directing T-cell responses might uncover further therapeutic targets. The efficacy of cyclosporin A and anti-CD4 treatment in patients with chronic severe asthma argues for continued T-cell involvement, but whether remodeling contributes to pathology inaccessible to anti-inflammatory treatment or T-cell immunotherapy will be an important future question.
Self-stretching of a perturbed vortex filament I: the asymptotic equation for deviations from a straight line

A new asymptotic equation is derived for the motion of thin vortex filaments in an incompressible fluid at high Reynolds numbers. This equation differs significantly from the familiar local self-induction equation in that it includes self-stretching of the filament in a nontrivial, but to some extent analytically tractable, fashion. Under the same change of variables as employed by Hasimoto (1972) to convert the local self-induction equation to the cubic nonlinear Schrodinger equation, the new asymptotic propagation law becomes a cubic nonlinear Schrodinger equation perturbed by an explicit nonlocal, linear operator. Explicit formulae are developed which relate the rate of local self-stretch along the vortex filament to a particular quadratic functional of the solution of the perturbed Schrodinger equation. The asymptotic equation is derived systematically from suitable solutions of the Navier-Stokes equations by the method of matched asymptotic expansions based on the limit of high Reynolds numbers. The key idea in the derivation is to consider a filament whose core deviates initially from a given smooth curve only by small-amplitude but short-wavelength displacements balanced so that the axial length scale of these perturbations is small compared to an integral length of the background curve but much larger than a typical core size δ=O(Re-1/2) of the filament. In a particular distinguished limit of wavelength, preturbation amplitude and filament core size the nonlocal induction integral has a simplified asymptotic representation and yields a contribution in the Schrodinger equation that directly competes with the cubic nonlinearity.
Binding of radioactively labeled saxitoxin to the squid giant axon.

The binding of saxitoxin, a specific inhibitor of the sodium conductance in excitable membranes, has been measured in giant axons from the squid,Loligo pealei. Binding was studied by labeling saxitoxin with tritium, using a solvent-exchange technique, and measuring the toxin uptake by liquid scintillation counting. Total toxin binding is the sum of a saturable, hyperbolic binding component, with a dissociation constant at 2–4°C of 4.3±1.7nm (meanse), and a linear, nonsaturable component. The density of saturable binding sites is 166±20.4 μm−2. From this density and published values of the maximum sodium conductance, the conductance per toxin site is estimated to be about 7 pS, assuming sequential activation and inactivation processes (F. Bezanilla & C.M. Armstrong, 1977,J. Gen. Physiol. 70: 549). This single site conductance value of 7 pS is in close agreement with estimates of the conductance of one open sodium channel from measurements of gating currents and of noise on squid giant axons, and is consistent with the hypothesis that one saxitoxin molecule binds to one sodium channel.