cssi/SciSciGPT-SciSciNet huggingface dataset:
Multi-rate and Multi-modal Characterization of an Advanced Poly(etherimide): Ultem 1000

The key to the effective implementation of polymers in structural applications is an understanding of the mechanical response under a variety of conditions. In this study, an unreinforced poly(etherimide) (PEI) known as Ultem 1000 was characterized under quasi-static and high-strain-rate loading. Standard tension, compression, and torsion experiments were conducted in order to investigate the multi-regime response of this material. The elastic response of the material to multiple loading conditions was correlated using the Ramberg–Osgood model. The effects of thermal and mechanical rejuvenation processes on the mechanical response were investigated; the upper yield strength of the material was reduced, and the strain softening regime responsible for strain localization was largely eliminated. The fracture toughness of the material was evaluated using a Charpy impact test, and the mechanisms of failure were shown to be brittle. The high-strain-rate response of the material to uniaxial compression was evaluated by means of a miniaturized split Hopkinson pressure bar, and the strain-rate dependence of the material was modeled using the Ree–Eyring equations. Finally, a combination of the Ramberg–Osgood model and a novel model was employed to correlate the elastoplastic response of rejuvenated PEI to quasi-static mechanical loading.
Giardia spp.: distribution of contractile proteins in the attachment organelle.

Abstract Giardia spp. trophozoites isolated from rat small intestine were examined by light microscopy, electron microscopy, SDS-gel electrophoresis, and immunocytochemistry. In SDS-gels of protein extracts of isolated Giardia spp. trophozoites protein bands corresponding to myosin, α-actinin, and actin were identified by comigration with avian myofibril proteins and molecular weight standards. Actin was specifically identified in SDS-gels by immunoautoradiography. Immunostaining for actin, α-actinin, myosin, and tropomyosin in trophozoites was demonstrated in the periphery of the ventral disc in an area corresponding to the lateral crest. Electron-dense fibrillar was observed in the lateral crest of the ventral disc by electron microscopy. Immunostaining for actin and α-actinin was also observed in the area of the median body, a microtubular organelle, and in electron-dense fibrillar material associated with the intracellular axonemes of the posterior-lateral flagella. The localization of these contractile proteins in the ventral disc suggests that they may play an important role in the mechanism of trophozoite attachment.
P01-254 - Living with tics: development and pilot examination of a psychosical treatment to improve resilience and coping in youth with tics

Objectives Many youth with tics experience distress about having tics and how others may perceive them. Such symptoms are often more impairing and distressing than are the tics and negatively impact self-concept, functioning, and quality of life. Although treatments exist that target the frequency and severity of tics, no intervention has been developed that helps youth with tics cope with their condition and limit associated functional impairment and distress. Given this, we developed a cognitive-behaviorally oriented psychotherapy protocol that promotes adaptive coping and resiliency among youth with tics in addressing varied issues commonly experienced by this population. This poster reports data from the Phase I component of this study. Method Phase I concentrated on developing the treatment protocol through expert opinion coupled with focus groups with parents and children with a tic disorder. Based on this, we developed a preliminary manual and piloted it in 6 youth with tics who met relevant inclusion/exclusion criteria. Phase II involves a preliminary test of the protocol in that focuses primarily on feasibility issues. All subjects participated in assessments (Screening, Baseline, Post-treatment) conducted by a blinded independent evaluator. Results Only Phase I data will be presented as Phase II is ongoing. Descriptive statistics related to improvement rates; tic severity; child self-esteem and self-efficacy; and child internalizing symptoms will be reported. Qualitative data from the focus groups will also be presented regarding domains of impairment for youth with tics. Conclusions This treatment shows early promise of helping youth with tics cope with their condition.
The dual of sweep

Abstract As an infinite union operation, sweep of a moving object through space is a powerful and natural addition to the Boolean set operations that incorporates motion-related information for the purposes of shaping, collision detection, and simulation of moving objects. Use of sweep has been hindered by limited computational support and by the fact that it is a ‘material growing’ operation, whereas many applications, such as interference elimination and mechanism design, appear to be better modeled by a ‘material removal’ operation. This article formally defines a new geometric modeling operation of unsweep . Given an arbitrary subset E of Euclidean space and a general motion M , unsweep ( E , M ) returns the largest subset of E that remains inside the original E under M . When M is a translation, unsweep ( E , M ) naturally reduces to the standard Minkowski difference of E and the trajectory generated by the inverted motion M . In this sense, the operation of unsweep is a generalization of Minkowski difference that corresponds to a ‘material removal’ operation, it can be also defined as an infinite intersection operation, and is the dual of sweep in a precise set-theoretic sense. We show that unsweep has attractive theoretical and computational properties, including a practical point membership test for arbitrary general motions. Using duality, the established properties of unsweep is extended to the general sweep operation, and can be used to improve the computational support for general sweeps.
Flexible, efficient and robust algorithm for parallel execution and coupling of components in a framework☆

We describe a general algorithm suitable for executing and coupling components of a software framework on a parallel computer. The requirements of a flexible, efficient and robust algorithm are defined precisely, and the motivation for the requirements is demonstrated on several examples. In short, the requirements are the following: (i) the algorithm should allow arbitrary distribution of processors among the components, (ii) it should allow arbitrary coupling schedule between the components, (iii) it should not use any inter-processor communication other than already required by the components and their couplings, and (iv) it should never get into a dead-lock. We show that the proposed algorithm based on the Temporal and Predefined Ordering of Tasks (TPOT) satisfies all these requirements. The TPOT algorithm has been implemented in the Space Weather Modeling Framework. The flexibility and efficiency of the algorithm is demonstrated with several examples.
A Control for Crayfish

(1965). A Control for Crayfish. The Progressive Fish-Culturist: Vol. 27, No. 4, pp. 184-184.
Light sea fermions in electron-proton and muon-proton interactions

The proton radius conundrum [Pohl et al., Nature 466, 213 (2010) and , Science 339, 417 (2013)] highlights the need to revisit any conceivable sources of electron-muon nonuniversality in lepton-proton interactions within the standard model. Superficially, a number of perturbative processes could appear to lead to such a nonuniversality. One of these is a coupling of the scattered electron into an electronic vacuum-polarization loop as opposed to a muonic one in the photon exchange of two valence quarks, which is present only for electron projectiles as opposed to muon projectiles. However, we show that this effect actually is part of the radiative correction to the proton's polarizability contribution to the Lamb shift, equivalent to a radiative correction to double scattering. We conclude that any conceivable genuine nonuniversality must be connected with a nonperturbative feature of the proton's structure, e.g., with the possible presence of light sea fermions as constituent components of the proton. If we assume an average of roughly $0.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}$ light sea positrons per valence quark, then we can show that virtual electron-positron annihilation processes lead to an extra term in the electron-proton versus muon-proton interaction, which has the right sign and magnitude to explain the proton radius discrepancy.
Friction, stability and the design of robotic finger

For practical reasons, compliant materials are often used on the gripping surfaces of robotic hands. Such materials are not well described by the Coulomb friction law or by simple point-contact or line-contact kinematics. In this paper, a shearing model is used to describe the contact friction. Models ofpointed, curved, flat, soft, and soft-curved fingertips are then developed and compared in terms of their contribu tion to the stiffness and stability of a simple grasp. There is a spectrum of contact conditions defined by the fingertip radius and contact area relative to the object size. This spectrum provides insights for designing and controlling robotic fingers.
Kinetics and reactions of hydrogen sulphide in solution of flooded rice soils

The sulphide-ion electrode was used to study the kinetics and reactions of free hydrogen sulphide in solution of flooded rice soils. The observed sulphide potential obeyed the Nernst equation over a range of sulphide-ion concentration from 10-1 to 10-19 M. Peak H2S concentrations were lowest in neutral soils high in iron and manganese; moderately high in soils low in iron or high in organic matter; and highest in acid sulphate soil low in iron. Harmful concentrations of H2S may be present in acid sulphate and acid soils low in iron during the first few weeks after flooding. The concentrations in acid sulphate soils can be drastically lowered by liming. There was thermodynamic evidence for the presence of FeS and ZnS in the solutions of most soils.
Influence of Multiple Anterior Pituitary Allografts on the Oestrous Cycle of the Syrian Hamster

TRANSPLANT studies of anterior pituitary tissue indicate that the hypothalamus exerts an inhibitory influence on the release of lactogenic hormone and that this hormone is luteotropic in the rat1. Comparable studies were undertaken as a preliminary investigation into the role of the pituitary in luteal maintenance in the hamster. Earlier studies indicate that autotransplants of anterior pituitary2,3 (1–4 days post coitum) to the cheek pouch or the kidney capsule of the pregnant hamster do not supply enough lactogenic hormone to cause the corpora lutea to secrete progesterone in amounts sufficient for nidation. It was noted2 that progesterone alone, in contrast with the rat4 which requires oestrogen for nidation, can maintain blastocysts through nidation in the ovariectomized hamster. Similarly, our results indicate that more than one allograft of anterior pituitary to the cheek pouch is necessary to influence the oestrous cycle of the hamster.
Selective synthesis of mixed alcohols catalyzed by dissolved base-activated highly dispersed slurried iron

Abstract An ultrafine Fe metal-based catalyst system that operates in a heterogeneous/homogeneous combination mode to selectively produce mixed (C 1 –C 4 ) alcohols from syngas is described. The Fe particles were generated via complete decomposition of Fe(CO) 5 in Ethylflo-164 hydrocarbon solvent at 225°C under N 2 in under 2 h. The resulting Fe particles, though somewhat aggregated, averaged 1 –C 4 alcohols over traditional hydrocarbons. Mossbauer measurements on quenched catalyst samples indicated that metallic and carbided Fe species (48% Fe, 38% γ -Fe 5 C 2 , 14% Fe 3 O 4 ) predominated in the hydrocarbon product-selective catalytic reaction, and fully oxidized Fe species (45% Fe 2 SiO 4 , 24% FeCO 3 , 22% Fe 2 O 3 , 9% Fe 3 O 4 ) were observed under catalytic conditions that predominantly yielded oxygenates. The implication of utilizing an inexpensive Fe-based catalytic system consisting of a slurried Fe (heterogeneous) and dissolved base (homogeneous) that effects CO hydrogenation to preferentially yield C 1 –C 4 mixed alcohols is discussed in relation to traditional base-doped Fe catalysts.
The ineligible patient: how to treat patients not included in clinical studies

Purpose Targeted therapies are currently the standard of care for metastatic renal cell carcinoma (mRCC). Five VEGF pathway inhibitors (sorafenib, sunitinib, bevacizumab in combination with interferon-alpha, pazopanib, and axitinib) and two mTOR inhibitors (everolimus and temsirolimus) are now FDA approved for mRCC based on results from phase III randomized clinical trials (RCTs). However, several subgroups of patients are excluded from enrollment due to strict eligibility criteria. The toxicity and efficacy of targeted therapies in these populations are unknown.
Cricothyroid muscle function and vocal fold stability in exercising horses.

Objectives— To determine (1) if the cricothyroid muscle had respiratory-related electromyographic (EMG) activity that increased with respiratory effort and (2) if bilateral cricothyroid myotomy resulted in vocal fold instability and collapse in exercising horses. Study Design— Experimental. Animals— Seven (3 EMG; 4 cricothyroid myotomy) Standardbred horses. Methods— Three horses exercised on a treadmill at speeds corresponding to the speed that produced maximum heart rate (HRmax), 75% of maximum heart rate (HR75%max), and 50% of maximum heart rate (HR50%max) for 60 seconds at each speed while EMG activity of the cricothyroid muscle and nasopharyngeal pressures were measured. Another 4 normal horses were exercised on the treadmill at HRmax and HR75%max for 60 seconds at each speed before and after bilateral cricothyroid myotomy. Upper airway pressures were measured and videoendoscopic examinations were performed and videotaped at each speed. Results— Peak phasic EMG activity of the cricothyroid muscle was coincident with inspiration and increased with treadmill speed. Bilateral cricothyroid myotomy resulted in vocal fold collapse in all horses. Mean peak inspiratory pressures were significantly more negative compared with control values at both HRmax and HR75%max. Conclusions— Cricothyroid muscle dysfunction may be implicated in vocal fold collapse and likely causes inspiratory airway obstruction in exercising horses. Clinical Relevance— Conditions compromising cricothyroid muscle function or motor innervation could result in vocal fold collapse.
Future directions in esophageal cancer

The incidence of esophageal cancer in the United States has been increasing in recent years. Since multimodality therapy for esophageal cancer has produced discouraging results, recent approaches have focused on molecular biological techniques, positron emission tomography, and minimally invasive surgery to improve pretreatment staging which will facilitate a more accurate assessment of new treatment. This article summarizes the results of studies investigating these approaches and outlines the strategy currently used at the University of Pittsburgh Medical Center.
Dopant states in a -Si: H. III. Triply coordinated boron

Boron atoms at trigonal, alloying sites are shown to be electronically active in $a$-Si: H. Alone among the dopant elements of groups III and V, boron produces deep gap states in this configuration. The position of a level depends on the bond angle of the site and thereby its occupation. We predict that there will be a conduction tail of empty levels and a long valence tail due to paramagnetic ${\mathrm{B}}_{3}^{\ensuremath{-}}$ sites. We discuss evidence that such states have been seen in luminescence, optical-absorption, and transport experiments.
Analysis of ifosfamide, 4-hydroxyifosfamide, N2-dechloroethylifosfamide, N3-dechloroethylifosfamide and iphosphoramide mustard in plasma by gas chromatography-mass spectrometry

A sensitive and specific method for the simultaneous quantitation of ifosfamide (IF), 4-hydroxylifosfamide (4-OHIF), N2-dechloroethylifosfamide (N2D), N3-dechloroethylifosfamide (N3D) and iphosphoramide mustard (IPM) has been developed using gas chromatography-mass spectrometry (GC-MS) with an ion-trap mass spectrometer. Deuterium labeled analogues for each of these analytes were synthesized as the internal standards. The labile 4-OHIF in plasma was first converted to the more stable cyanohydrin adducts before dichloromethane extraction. IPM was extracted by C18 reversed-phase resin. All analytes were converted to their silyl derivatives before GC-MS analysis. The sensitivity limits ranged from 0.1 to 0.5 microgram/ml when 100 microliters of plasma was used. This method was validated with within-run coefficients of variation less than 5% (n = 8) and between-run coefficients of variation less than 12% (n = 6). The method was applied to the determination of plasma levels of IF and metabolites in the rat.
Role of the beta2 adrenoceptor in mediating positive inotropic activity in the failing heart and its relation to the hemodynamic actions of dopexamine hydrochloride

In patients with severe congestive heart failure, it has been suggested that since myocardial β 1 adrenoceptors are selectively down-regulated, activation of β 2 receptors may be a preferable approach to augmenting contractility. Accordingly, dopexamine hydrochloride (1, 2 and 4 μg/kg/min) and dopamine (2 and 4 μg/kg/min) were administered to 8 patients with dilated cardiomyopathy. Left ventricular (LV) dimensions, thicknesses and pressures were obtained using simultaneous high-fidelity pressure measurements and echocardiographic recordings. LV contractility was assessed using the load-independent relation between LV end-systolic wall stress and rate-corrected velocity of fiber shortening. Cardiac index increased in a dose-related manner with both drugs, and was accompanied by a decline in systemic vascular resistance, a measure of peripheral arteriolar tone. LV end-diastolic pressure was unaltered except for a decrease from 29 ± 6 to 19 ± 5 mm Hg (p Thus, dopamine and dopexamine hydrochloride improved overall LV performance. With dopamine, a substantial positive inotropic effect occurred in association with a reduction in LV afterload. The increased cardiac index observed with dopexamine hydrochloride was due primarily to peripheral vasodilatation and a positive chronotropic effect. Dopexamine hydrochloride exhibited less positive inotropic activity than dopamine in patients with severe congestive heart failure.
Stereotype Threat and Executive Functions: Which Functions Mediate Different Threat-Related Outcomes?

Stereotype threat research shows that women’s math performance can be reduced by activating gender-based math stereotypes. Models of stereotype threat assert that threat reduces cognitive functioning, thereby accounting for its negative effects. This work provides a more detailed understanding of the cognitive processes through which stereotype threat leads women to underperform at math and to take risks, by examining which basic executive functions (inhibition, shifting, and updating) account for these outcomes. In Experiments 1 and 2, women under threat showed reduced inhibition, reduced updating, and reduced math performance compared with women in a control condition (or men); however, only updating accounted for women’s poor math performance under threat. In Experiment 3, only updating accounted for stereotype threat’s effect on women’s math performance, whereas only inhibition accounted for the effect of threat on risk-taking, suggesting that distinct executive functions can account for different ste...
Evaluation of silica-water surface chemistry using NMR spectroscopy

We have combined traditional batch and flow-through dissolution experiments, multinuclear nuclear magnetic resonance (NMR) spectroscopy, and surface complexation modeling to re-evaluate amor- phous silica reactivity as a function of solution pH and reaction affinity in NaCl and CsCl solutions. The NMR data suggest that changes in surface speciation are driven by solution pH and to a lesser extent alkali concentrations, and not by reaction time or saturation state. The 29 Si cross-polarization NMR results show that the concentration of silanol surface complexes decreases with increasing pH, suggesting that silanol sites polymerize to form siloxane bonds with increasing pH. Increases in silica surface charge are offset by sorption of alkali cations to ionized sites with increasing pH. It is the increase in these ionized sites that appears to control silica polymorph dissolution rates as a function of pH. The 23 Na and 133 Cs NMR results show that the alkali cations form outersphere surface complexes and that the concentration of these complexes increases with increasing pH. Changes in surface chemistry cannot explain decreases in dissolution rates as amorphous silica saturation is approached. We find no evidence for repolymerization of the silanol surface complexes to siloxane complexes at longer reaction times and constant pH. Copyright © 2002 Elsevier Science Ltd
The therapy threshold within the Medicare prospective payment system: associated ethical dilemmas and influence of therapy practice patterns and quality of patient care.

This mixed-methods study of therapists and therapy managers from home health agencies in northeastern Pennsylvania found that the therapy threshold does affect practice patterns, although not negatively. It does not consistently put therapists in an ethical dilemma and does not negatively impact qua
On the nature of selective olefin oxidation catalysts derived from molybdate- and tungstate-intercalated layered double hydroxides

Abstract Catalysts derived from Mg 2 Al layered double hydroxides (LDHs) intercalated by polyoxometalates (POMs) of molybdenum and tungsten have been previously reported to exhibit substrate shape selectivity in condensed phase olefin oxidations. On the basis of X-ray powder diffraction, Raman spectroscopy, and nitrogen adsorption studies of these and related Zn 2 Al-LDH-POM systems, the present work elucidates the catalyst precursors in terms of mixtures of salt-like and interlayered LDH phases containing Mo 7 O 24 6− and W 7 O 24 6− . Under the conditions used to dry the precursors prior to catalysis (120°C), the LDH components are transformed into layered decomposition products that act as the active catalysts. Substrate selectivity based on the preferred access to the intragallery sites of pillared LDH phases is precluded under catalytic conditions. Even a structurally stable Zn 2 Al H 2 W 12 O 40 6− -LDH catalyst lacks the intragallery microporosity needed for shape selective substrate access to intragallery active sites under condensed phase reaction conditions. Other factors, perhaps selective adsorption based on substrate polarity, are responsible for the observed selectivity.
Exciton dynamics in single-walled nanotubes: Transient photoinduced dichroism and polarized emission

Ultrafast relaxation of photoexcitations in semiconducting single-walled carbon nanotubes ($S$-NTs) were investigated using polarized pump-probe photomodulation (with 150 fs time resolution) and cw polarized photoluminescence (PL). Both annealed and unannealed thin NT films and ${\mathrm{D}}_{2}\mathrm{O}$ solutions of isolated NTs were investigated. Various transient photoinduced bleaching (PB) and photoinduced absorption (PA) bands, which show photoinduced dichroism, were observed in the ultrafast photomodulation spectra of all NT forms. The PA and PB decay dynamics as a function of time, $t$, follow a power law, ${(t)}^{\ensuremath{-}\ensuremath{\alpha}}$ with $\ensuremath{\alpha}$ in the range of 0.7 to 1. Whereas the PA bands in $S$-NTs in solution uniformly decay, the PB bands, in contrast, have different decay dynamics across the spectrum, which originates from an ultrafast spectral shift. Nevertheless the dynamics of the PA and PB bands for NTs in solution are the same when the spectral shift is accounted for, indicating a common origin. In addition $S$-NTs in ${\mathrm{D}}_{2}\mathrm{O}$ solution show polarized PL emission bands in the mid infrared spectral range that follow almost exactly the infrared absorption peaks of the isolated NTs, as well as their transient PB spectrum. The PL emission shows a degree of polarization that agrees with that of the transient photoinduced dichroism. We therefore conclude that the primary photoexcitations in $S$-NTs are not free carriers, rather they are excitons that are confined along the nanotubes. We found that the transient relaxation kinetics of the excitons depend on the NT form. The fastest exciton dynamics (with sub-picosecond lifetime) characterizes the annealed film, whereas the slowest dynamics (with lifetime of tens of ps) characterizes the isolated NTs in ${\mathrm{D}}_{2}\mathrm{O}$ solution. From the polarization memory decay we could estimate the diffusion constant, $D$, and the diffusion length, ${L}_{D}$, of the excitons along the nanotube. For the annealed films at room temperature we found $D\ensuremath{\approx}100\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{2}\phantom{\rule{0.2em}{0ex}}{\mathrm{s}}^{\ensuremath{-}1}$ and ${L}_{D}\ensuremath{\approx}100\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$. From the average PL polarization degree, which remains constant across the PL spectrum, and the transient polarization memory decay, we estimate the PL lifetime in NT solution to be of the order of 500 ps. This relatively long PL lifetime is dominated by nonradiative decay processes, which when coupled with the minute PL emission quantum efficiency indicates a very small radiative recombination rate. The weak radiative transition strength is consistent with recent excited state calculations that include electron-hole interaction, which predict that excitons in NTs are basically dark.
Layers With Nonsmooth Interface in a Semilinear Elliptic Problem

(1992). Layers With Nonsmooth Interface in a Semilinear Elliptic Problem. Communications in Partial Differential Equations: Vol. 17, No. 9-10, pp. 1695-1708.
HISTOLOGICAL CHANGES DURING THE DEVELOPMENT OF THE BOVINE NUCHAL LIGAMENT

The histological changes occurring during the development of the bovine nuchal ligament have been observed in sections of formalin-fixed material from 21 animals ranging in age from 110 days of gestation to 10 yr. The elastic fibers which constitute the bulk of the adult ligament were initially few in number. During fetal development, the fibers showed a rapid increase both in number and in their stainability with the usual elastic stains. The average diameter of these elastic fibers increased only slowly until the last uterine month, at which time it began to increase very rapidly. This rapid rate of increase continued through the first 6 postnatal months, after which the rate of increase slowed markedly. However, the fiber diameter continued to rise steadily throughout the period of the study. During the fetal stage of development, the fibroblastic cells of the ligament exhibited unusual nuclear appearances which distinguish them from other fibroblasts. These consisted of marked clumping of the chromatin and an associated nuclear vacuolation or vesiculation. While these changes seem likely to be artefacts of fixation, their temporal correlation with elastin deposition and their demonstration in other tissue cells engaged in elastin production suggest that the factors responsible for these appearances may be related to elastin synthesis.
An assessment of county programs to reduce driving while intoxicated

The safety effects of three programs designed to reduce driving while intoxicated (DWI) in Bergen County, New Jersey, have been examined, using a number of time-series models. The results indicate that Strike Force, primarily a road checkpoint program, produced significant and lasting reductions in single vehicle night-time accidents, a proxy for alcohol-involved accidents, and similar but less consistent reductions in single vehicle night-time fatalities. Two programs emphasizing education and publicity about the dangers of intoxicated driving appear to have smaller and briefer effects.(A)
Characteristics of beef batters as influenced by electrical stimulation and postmortem salting time

Changes were evaluated in functional and textural properties of beef batters altered by mincing, postmortem salting time and electrical stimulation. Histological examinations showed raw batters from non-stimulated (NS) meat exhibited uniform fat dispersal throughout the protein matrix regardless of salting time; however, fat channeling, increased fat and gel-water release, lower hardness and gel strength along with reduced apparent viscosity were observed in electrically stimulated (ES) meat when salting was delayed. Changes in amounts of salt-soluble protein were not consistent. Effects of pH on water-holding capacity and myofibrillar swelling accounted for most changes observed in batters from ES muscles. However, increases in apparent viscosity and hardness may have been a consequence of rigor onset.
Ecological Consequences of Altering the Timing Mechanism for Metamorphosis in Anural Ascidians

Synopsis. In the present study the timing of metamorphosis in an anural ascidian, Molgula pacifica, was compared to metamorphosis in a urodele species Boltenia villosa. Metamorphosis in M. pacifica was triggered at a fixed time in development (32-36 hours after fertilization), just prior to hatching. In contrast, metamorphosis was triggered in B. villosa after the hatched larvae responded to substrate cues. The timing of metamorphosis in B. villosa was often delayed for up to four days, whereas delays in M. pacifica were not observed. An antibody, termed Epi-3, was found to cross-react exclusively with epidermal cells in both species. The binding of FITC-labelled Epi-3 was very low prior to metamorphosis and then it increased dramatically after metamorphosis was triggered. The cytoplasm of ampulla tip cells and the tunic immediately surrounding each ampulla showed the highest levels of Epi-3 fluorescence. The histological and ultrastructural features of the ampulla cells suggest that Epi-3 antibody recognizes granules localized in the apical cytoplasm. How the evolution of an internal "clock" mechanism responsible for initiating metamorphosis may be beneficial to anural species is discussed. One possibility is that the anural type of timing mechanism reduces mor? tality rates during this critical phase of its life cycle.
Growth and characterization of interfaces in p-type InGaAs/InP quantum-well infrared photodetectors with ultra-thin quantum wells

P-type InGaAs/InP quantum-well infrared photodetectors operated at 4.55 μm require the growth of ultra-thin (10 A) quantum wells. We report a study of interfaces in QWIPs grown by gas-source molecular beam epitaxy in which we optimized the group V source supply sequence so that a 6 K photoluminescence linewidth as narrow as 8.4 meV was observed from a structure with 10 A wells. Analysis of the PL suggests that interface roughness was minimized. Cross-sectional scanning tunneling microscopy, double crystal x-ray diffraction, and cross-sectional tunneling electron microscopy confirmed that high-quality interfaces and uniform layers were obtained. Using the derived structural parameters, photocurrent spectral response was theoretically predicted for these QWIPs and then experimentally verified.
Protein kinase inhibitor blocks the activation of a myocardial triacylglycerol lipase

Purified inhibitor of the cyclic AMP-dependent protein kinase (PKI) has been used as a probe to determine if hormone and cyclic AMP-induced activation of the cardiac alkaline triacylglycerol(TG) lipase is mediated through the cAMP-dependent protein kinase. Addition of CAM (cyclic AMP, Mg-ATP, and 3-isobutyl, 1-methylxanthine) to any of the four fractions (homogenate, 10 000 g supernatant, 105 000 g supernatant, or heparin-Sepharose eluate) from heparin perfused heart activated the TG lipase 60% to 110%. Preincubation of these fractions with 33 ng of PKI had no effect on control enzyme activity. Addition of PKI (33 ng) to extracts following CAM activation had little effect on homogenate TG lipase activity, but reduced activities in 10 000 g and 105 000 g supernatant fractions to their respective control levels, and inhibited TG hydrolase activity of activated heparin-Sepharose eluate to 50% below the control activity. If extracts were preincubated with PKI prior to CAM addition, TG lipase activity was reduced to approximately 50% below control levels in all fractions. PKI addition (33 ng) to 105 000 g supernatant obtained from hearts stimulated 60% by epinephrine perfusion reduced activity to 50% below the control level. PKI inhibition of TG lipase activity of 105 000 g supernatant could be reversed by adding 0.5 μg of catalytic subunit of protein kinase (PKC) to the extract. The inhibition below control levels caused by CAM and PKI indicate that the PKI-PKC complex by itself or in combination with other extract molecules, has an inhibitory effect on the TG lipase. The data obtained here are consistent with the hypothesis that cyclic AMP-activation of the cardiac TG lipase is mediated through protein kinase, possibly through a protein phosphorylation.
Mechanism of auxiliary β-subunit-mediated membrane targeting of L-type (CaV1.2) channels

Ca(2+) influx via Ca(V)1/Ca(V)2 channels drives processes ranging from neurotransmission to muscle contraction. Association of a pore-forming α(1) and cytosolic β is necessary for trafficking Ca(V)1/Ca(V)2 channels to the cell surface through poorly understood mechanisms. A prevalent idea suggests β binds the α(1) intracellular I-II loop, masking an endoplasmic reticulum (ER) retention signal as the dominant mechanism for Ca(V)1/Ca(V)2 channel membrane trafficking. There are hints that other α(1) subunit cytoplasmic domains may play a significant role, but the nature of their potential contribution is unclear. We assessed the roles of all intracellular domains of Ca(V)1.2-α(1C) by generating chimeras featuring substitutions of all possible permutations of intracellular loops/termini of α(1C) into the β-independent Ca(V)3.1-α(1G) channel. Surprisingly, functional analyses demonstrated α(1C) I-II loop strongly increases channel surface density while other cytoplasmic domains had a competing opposing effect. Alanine-scanning mutagenesis identified an acidic-residue putative ER export motif responsible for the I-II loop-mediated increase in channel surface density. β-dependent increase in current arose as an emergent property requiring four α(1C) intracellular domains, with the I-II loop and C-terminus being essential. The results suggest β binding to the α(1C) I-II loop causes a C-terminus-dependent rearrangement of intracellular domains, shifting a balance of power between export signals on the I-II loop and retention signals elsewhere.
Fair Elections; Polls; Amendments

We have seen several different electoral systems. Even in a small election, the same preferences can give rise to a different results depending on the system used. In this section we shall present an extreme case of how the method chosen might affect the outcome of an election in a realistic situation. This means that an electoral system could be chosen in order to favor one or another candidate.
Laser Rayleigh scattering

Rayleigh scattering is a powerful diagnostic tool for the study of gases and is particularly useful for aiding in the understanding of complex flow fields and combustion phenomena. Although the mechanism associated with the scattering, induced electric dipole radiation, is conceptually straightforward, the features of the scattering are complex because of the anisotropy of molecules, collective scattering from many molecules and inelastic scattering associated with rotational and vibrational transitions. These effects cause the scattered signal to be depolarized and to have spectral features that reflect the pressure, temperature and internal energy states of the gas. The very small scattering cross section makes molecular Rayleigh scattering particularly susceptible to background interference. Scattering from very small particles also falls into the Rayleigh range and may dominate the scattering from molecules if the particle density is high. This particle scattering can be used to enhance flow visualization and velocity measurements, or it may be removed by spectral filtering. New approaches to spectral filtering are now being applied to both Rayleigh molecular scattering and Rayleigh particle scattering to extract quantitative information about complex gas flow fields. This paper outlines the classical properties of Rayleigh scattering and reviews some of the new advances in flow field imaging that have been achieved using the new filter approaches.
An uncorrelated relaxed-clock analysis suggests an earlier origin for flowering plants

We present molecular dating analyses for land plants that incorporate 33 fossil calibrations, permit rates of molecular evolution to be uncorrelated across the tree, and take into account uncertainties in phylogenetic relationships and the fossil record. We attached a prior probability to each fossil-based minimum age, and explored the effects of relying on the first appearance of tricolpate pollen grains as a lower bound for the age of eudicots. Many of our divergence-time estimates for major clades coincide well with both the known fossil record and with previous estimates. However, our estimates for the origin of crown-clade angiosperms, which center on the Late Triassic, are considerably older than the unequivocal fossil record of flowering plants or than the molecular dates presented in recent studies. Nevertheless, we argue that our older estimates should be taken into account in studying the causes and consequences of the angiosperm radiation in relation to other major events, including the diversification of holometabolous insects. Although the methods used here do help to correct for lineage-specific heterogeneity in rates of molecular evolution (associated, for example, with evolutionary shifts in life history), we remain concerned that some such effects (e.g., the early radiation of herbaceous clades within angiosperms) may still be biasing our inferences.
Ab initio studies of the x-ray absorption edge in copper complexes. I. Atomic Cu 2 + and Cu(ii) Cl 2

As a first step in the study of the structure at x-ray absorption edges, we have examined the discrete transitions corresponding to the atomic $1s\ensuremath{\rightarrow}3d, 4s, 4p, 5s, \mathrm{and} 5p$ transitions and the corresponding shakeup processes for Cu atom and for a Cu(ii) model system, Cu${\mathrm{Cl}}_{2}$. For Cu${\mathrm{Cl}}_{2}$ the lowest strong transitions have the character $1s\ensuremath{\rightarrow}4p$ ($f=0.00133$). About 7.5 eV lower is a group of transitions involving $1s\ensuremath{\rightarrow}4p$ simultaneous with ligand-to-metal shakedown. About 18.7 eV below the main peak is a weak (65 times weaker) quadrupole-allowed transition corresponding to $1s\ensuremath{\rightarrow}3d$ (i.e., $1{s}^{2}3{d}^{9}\ensuremath{\rightarrow}1{s}^{1}3{d}^{10}$). These results are in agreement with typical assignments of x-ray absorption spectra of Cu(ii) systems except that the middle transition is usually assigned as $1s\ensuremath{\rightarrow}4s$, whereas we find this transition to be $1s\ensuremath{\rightarrow}4p$ plus shakedown. (Transitions of the character $1s\ensuremath{\rightarrow}4s$ are calculated but have intensities far too low to have been observed.)
A constrained-optimization approach to training neural networks for smooth function approximation and system identification

A constrained-backpropagation training technique is presented to suppress interference and preserve prior knowledge in sigmoidal neural networks, while new information is learned incrementally. The technique is based on constrained optimization, and minimizes an error function subject to a set of equality constraints derived via an algebraic training approach. As a result, sigmoidal neural networks with long term procedural memory (also known as implicit knowledge) can be obtained and trained repeatedly on line, without experiencing interference. The generality and effectiveness of this approach is demonstrated through three applications, namely, function approximation, solution of differential equations, and system identification. The results show that the long term memory is maintained virtually intact, and may lead to computational savings because the implicit knowledge provides a lasting performance baseline for the neural network.
INFOSEC considerations for tactical key management in the IRIS radio system

Recent developments in electronic key management systems offer the opportunity for improved security and administrative effectiveness with lower operational cost. Key distribution is a subset of a total information management system designed to provide responsive and efficient use of communications resources. The IRIS crypto-material management system (CMMS) supports the communications management system (CMS) to provide an integrated communications and security management function. The author describes the hardware and software architecture that provides security and INFOSEC protection for the critical key management functions. Distribution of keying material in black form significantly reduces the risk of compromise. The CMMS is a portable-data-terminal-based software program used to perform the cryptonet engineering and the net management functions of the CMS. Operational requirements include planning for key distribution, cryptonet reconfiguration due to force restructuring, compromise recovery, reporting, accounting of all crypto material, and personal security information. >
Controlling the false discovery rate and increasing statistical power in ecological studies

ABSTRACT Ecologists routinely use Bonferroni-based methods to control the alpha inflation associated with multiple hypothesis testing, despite the aggravating loss of power incurred. Some critics call for abandonment of this approach of controlling the familywise error rate (FWER), contending that too many unwary researchers have adopted it in the name of scientific rigour even though it often does more harm than good. We do not recommend rejecting multiplicity correction altogether. Instead, we recommend using an alternative approach. In particular, we advocate the Benjamini–Hochberg and related methods for controlling the false discovery rate (FDR). Unlike the FWER approach, which safeguards against falsely rejecting even a single null hypothesis, the FDR approach controls the rate at which null hypotheses are falsely rejected (i.e., false discoveries are made). The FDR approach represents a compromise between outright refusal to control for multiplicity, which maximizes alpha inflation, and strict adhe...
Aortic Stiffness Is Associated With Visceral Adiposity in Older Adults Enrolled in the Study of Health, Aging, and Body Composition

The central arteries stiffen with age, causing hemodynamic alterations that have been associated with cardiovascular events. Changes in body fat with age may be related to aortic stiffening. The association between vascular stiffness and body fat was evaluated in 2488 older adults (mean age, 74 years; 52% female; 40% black) enrolled in the Study of Health, Aging, and Body Composition (Health ABC), a prospective study of changes in weight and body composition. Clinical sites were located in Pittsburgh, Pa, and Memphis, Tenn. Aortic pulse wave velocity was used as an indirect measure of aortic stiffness. A faster pulse wave velocity indicates a stiffer aorta. Body fat measures were evaluated with dual energy x-ray absorptiometry and computed tomography. Independent of age and blood pressure, pulse wave velocity was positively associated with weight, abdominal circumference, abdominal subcutaneous fat, abdominal visceral fat, thigh fat area, and total fat (P<0.001 for all). The strongest association was with abdominal visceral fat. Elevated pulse wave velocity was also positively associated with history of diabetes and higher levels of glucose, insulin, and hemoglobin A1c (P<0.001 for all). In multivariate analysis, independent positive associations with pulse wave velocity were found for age, systolic blood pressure, heart rate, abdominal visceral fat, smoking, hemoglobin A1c, and history of hypertension. The association between pulse wave velocity and abdominal visceral fat was consistent across tertiles of body weight. Among older adults, higher levels of visceral fat are associated with greater aortic stiffness as measured by pulse wave velocity.
Don’t Children Grow Out of Their Obesity? Weight Transitions in Early Childhood

Background. Expert opinion and cross-sectional analyses posit that obese young children will likely “outgrow” their obesity. However, given the nature of the US childhood obesity epidemic, this assertion may no longer hold true. Objective. To compare the weight transitions between early childhood (3-5 years) and midchildhood (7-10 years) in 2 different longitudinal cohorts: black preschool children from the inner city and from a nationally representative sample. Results. Weight transitions for children who were normal weight at baseline were not markedly different between cohorts. However, overweight and obese low-income black children had a very high probability of becoming or remaining overweight or obese by follow-up (>90% probability) in comparison with the nationally representative cohort (50%-60% probability). Conclusion . Low-income black preschool children do not necessarily “outgrow” their obesity. These findings have implications for optimal timing of obesity interventions and suggest the need f...
Density-Dependent Patch Selection by Foraging Cattle Egrets

Abstract According to habitat selection theory, individuals selecting among habitat patches should either avoid or be attracted to conspecifics. This study examined Cattle Egrets (Bubulcus ibis) foraging around two grazing horses (Equus caballus), which represented two distinct habitat patches. The numbers of Cattle Egrets in the two patches were not significantly different, and the egrets were regularly distributed between the two patches. When settling in the two patches, 66% of the egrets selected the patch occupied by fewer conspecifics. All egrets choosing the patch occupied by more conspecifics did so only when the numbers of egrets in the two patches differed by one egret. When the numbers of egrets in the two patches differed by two or more egrets, newly arriving birds always chose the patch occupied by fewer conspecifics. As the number of egrets within a patch increased, nearest-neighbor distances decreased, and rates of aggression increased. Thus, these results indicate that the Cattle Egrets av...
What to do about the boys? Advocating for system change when doing social justice work with girls

Girls‟ Studies has been a quickly growing field, which has included work focused on interventions designed to improve the lives of girls. Programs have been developed and utilized to address eating disorders and body image concerns, self-esteem, access to math and science mentors, experiences of sexism, and others. In this paper, we describe a social justice intervention designed to recognize and increase girls‟ resiliency. First, we provide a brief overview of current research and programming with girls and boys to provide a context for the intervention and the challenges that arose. Next, we describe how we navigated within a school system, managed mixed support from school personnel, and addressed male students‟ backlash about the girls‟ participation in the program. We include information from workshops and interviews with the adolescent girls to highlight their voices regarding their experiences of interpersonal sexism with their male classmates. We conclude with three key lessons we learned from this work, including the need to: address the systems in which girls live, consider the implications of an “empowerment” model, and anticipate possible areas of resistance. We pose these lessons in the hopes that we can contribute to dialogues amongst researchers, counselors, and scholars who are engaged in social change work and face challenges or barriers that may arise while doing this work.