cssi/SciSciGPT-SciSciNet huggingface dataset:
Efficacy of FDA guidelines for ordering radiographs for caries detection

This study evaluated the effect on caries diagnosis of using the Food and Drug Administration (FDA) guidelines for ordering radiographs on a sample of new adult patients seeking general dental care at a dental school clinic. These guidelines recommend posterior bitewing views accompanied by supplemental periapical views as indicated by the patient's clinical signs or symptoms. We compared the findings from the use of this protocol to those from a full-mouth set of radiographs made on the same new patient. We examined 490 patients and ordered periapical radiographs in accordance with the FDA guidelines, namely, when there was some clinical sign or symptom suggesting the need for radiographs. A full-mouth set of radiographs was obtained, and both the full and selected sets were evaluated separately. We found that 95% of our patients had one or more carious lesions, with an average of 5.7 carious teeth per patient. Of the 2808 carious teeth detected in the study, 1949 (69%) were found radiographically and 1564 (56%) were found clinically. Indeed, 1244 (44%) of the carious teeth were detected only by radiographic examination. Use of the FDA guidelines resulted in a 43% reduction in the number of radiographs ordered. Reduction in the number of images made on patients resulted in failure to detect 93 lesions (3.3%) located on 88 teeth in 11.4% of the study patients. Most of the missed lesions (2.9%) were radiographically confined to the enamel of anterior maxillary teeth. Only 36 of the missed lesions (1.6% of all radiographic lesions) extended into the dentin. We believe that this number is very small and most likely inconsequential compared with the considerable diversity among dentists regarding radiographic detection of caries, as well as the diversity of opinion regarding the indications for restorative treatment.
Technetium-99m tetrofosmin: Use for myocardial perfusion imaging in the detection of coronary artery disease

Correspondence: He D’Arceuil Department of Radiology, H0100, Nuclear Medicine Imaging Laboratory, Stanford University School of Medicine, 300 Pasteur Drive, Stanford, CA 94303, USA Tel +1 650 725 1147 email helen@nmr.mgh.harvard.edu Abstract: Technetium-99m tetrofosmin is a radioactive tracer which is designed for myocardial perfusion imaging. Differential tracer uptake allows discrimination between normal and ischemic myocardium. Technetium-99m tetrofosmin has shown excellent utility as a safe, cost-effective, and technically sound agent for use in the diagnosis of coronary artery disease. This paper provides an overview of the available literature on clinical applications of technetium-99m tetrofosmin, and shows how this tracer has gained widespread acceptance as a diagnostic aid since its inception approximately 17 years ago. The various cardiac imaging modalities and imaging protocols which have employed this agent are also briefly reviewed.
Enabling nanomaterial, nanofabrication and cellular technologies for nanoneuromedicines.

Nanoparticulate delivery systems represent an area of particular promise for nanoneuromedicines. They possess significant potential for desperately needed therapies designed to combat a range of disorders associated with aging. As such, the field was selected as the focus for the 2014 meeting of the American Society for Nanomedicine. Regenerative, protective, immune modulatory, anti-microbial and anti-inflammatory products, or imaging agents are readily encapsulated in or conjugated to nanoparticles and as such facilitate the delivery of drug payloads to specific action sites across the blood-brain barrier. Diagnostic imaging serves to precisely monitor disease onset and progression while neural stem cell replacement can regenerate damaged tissue through control of stem cell fates. These, taken together, can improve disease burden and limit systemic toxicities. Such enabling technologies serve to protect the nervous system against a broad range of degenerative, traumatic, metabolic, infectious and immune disorders.
A classification theory for quantizable dynamical systems

Abstract Quantizable dynamical systems are classified by the path space of the base (phase) space. From this theory the results on classification in canonical quantitzation due to Keller, Segal, Souriau and Kostant are directly derived. The relationship to group extensions is briefly mentioned.
The Cephalic Index is not different among groups of children aged 36-48 months with chronic otitis media with effusion, recurrent acute otitis media and controls.

Abstract Objectives The Cephalic Index, an anthropometric measure of head shape, was reported to be different between individuals with and without signs of past or concurrent otitis media (OM). In this study, we compared the Cephalic Index and other measures of head shape among groups of children aged 36–48 months with a documented history of chronic OM with effusion (COME), recurrent acute OM (RAOM) and CONTROLS (few to no OM episodes) to test that hypothesis. Methods In 41 CONTROL, 36 COME and 42 RAOM children, Maximum Head Width, Maximum Head Length and Head Circumference were measured and the Cephalic Index (Head Width/Head Length × 100) was calculated. The four measures were compared among the three groups using a General Linear Model that included group, sex and race as factors and age as a covariate. Results There were no differences among groups in the Cephalic Index or Head Length. Head Width was significantly smaller in the RAOM when compared to the CONTROL group and Head Circumference was significantly smaller in the RAOM and COME groups when compared to the CONTROL group. For all measures, the distribution of values showed significant overlap among groups. Conclusions These results do not support the hypothesis that the Cephalic Index is different between young children with and without OM, but did document differences in Head Width and Circumference among groups. However, the large overlap in each measure for the three groups suggests that none capture sufficient information on Eustachian tube anatomy to predict disease presentation.
Power and Type I Error Rates of New Pairwise Multiple Comparison Procedures Under Heterogeneous Variances

Abstract The Type I error rates and statistical power of 9 selected multiple comparison procedures were compared in a Monte Carlo study. Data were generated for 3-, 4-, and 5-group ANOVA models, from simulated populations with both homogeneous and heterogeneous variances. A variety of patterns of population means were examined, including completely null, partial-null, and multiple-null patterns. None of the procedures was robust to violations of the assumption of variance homogeneity at nominal alpha levels lower than .10, even with equal sample sizes. The Dunn procedure and modified Bonferroni procedures showed better robustness properties than the Tukey procedure and recent modifications of it did. Power comparisons, conducted at a nominal alpha level of .10, showed the Peritz, Ryan, and Fisher-Hayter tests to be consistently most powerful across the variance conditions examined. However, power differences among these three procedures were minimal.
Toward Comparative Studies of the U.S. Militia Movement

The purpose of this paper is to place the U.S. militia movement into proper historical context through the use of a comparative method. Militias in the United States are often depicted as dangerous and extreme right-wing groups that warrant significant monitoring and control. The sense of danger associated with the militias is perhaps exacerbated by the tendency to think of these groups as an unprecedented social phenomenon. Early reports of U.S. militias in news reports tended to neglect the historical forerunners of this movement, and this omission promoted the view that militias are unique developments. Expanding upon work by Durham (1996), this article seeks to deepen our historical appreciation of U.S. militias. Beginning with the observation that comparative studies of the militia movement have been hampered by a failure to systematically define the subject of study, we employ five analytic categories — ideology, motivation, mobilization, organization, and ritual — in an effort to describe U.S. militias. Having outlined these categories and applied them to U.S. militias, we then compare and contrast the militias with right-wing forerunners in the United States such as the Silver Shirts, KKK, and Know Nothing Party. We conclude with several suggestions for advancing comparative investigations into the U.S. militia movement.
On convergence of random linear functionals

Abstract When is the pointwise limit of the characteristic functions of a sequence { X n } of random elements taking values in a real separable Hilbert space H the characteristic function of a H valued random element? Uniform tightness of { ∥ X n ∥ : n ⩾ 1 } is sufficient, but not necessary, whereas uniform tightness of { 〈 X n , y 〉 : n ⩾ 1 , ∥ y ∥ ⩽ 1 } is necessary, but not sufficient. The sufficiency statement extends to a separable reflexive Banach space, whereas the necessity statement extends to a Banach space with separable dual.
FOREWORD: ANTI-ANGIOGENIC THERAPY: MAXIMIZING THERAPEUTIC GAIN

P 9 n June 25, 2004, the Radiation Therapy Oncology Group RTOG, www.rtog.org) held a symposium, “Anti-Angiogenic herapy: Maximizing Therapeutic Gain,” in Washington, .C., in conjunction with the RTOG’s semi-annual meeting. The symposium brought together a diverse group of linicians and basic scientists, leading experts in the field, to oster the development of innovative research in multicenter ooperative group projects. The topics covered were the ollowing: role of angiogenesis in normal tissue biology and ancer cell biology, mechanism of action in tumor-growth nhibition of selective anti-angiogenic inhibitors, effects of nti-angiogenic inhibitors on preclinical tumor models
A degree-theoretic approach to parametric nonsmooth equations with multivalued perturbed solution sets

This paper studies the sensitivity of a parametric nonsmooth equation using degree theory and set-valued analysis. Under the assumption of existence of an approximating function of a certain kind, we investigate the existence, continuity, and differentiability of the set-valued solutions of the parametric equation. Our analysis is a synthesis of the work of several authors (King and Rockafellar, 1992; Gowda and Pang, 1991; Robinson, 1991). Applications of the derived results to the convergence of Newton's method and to the sensitivity analysis of parametric complementarity problems and variational inequalities will be discussed.
Body Size and Hip Fracture Risk in Older Women: A Prospective Study

Abstract PURPOSE: To determine the relationship between measures of body size and the risk of hip fracture in elderly women. PARTICIPANTS AND METHODS: The association between measures of body size and hip fracture risk was assessed in 8,011 ambulatory, nonblack women 65 years of age or older enrolled in the Study of Osteoporotic Fractures with measurements of total body weight, percent weight change since age 25, hip girth, lean mass, fat mass, percent body fat, body mass index, modified body mass index, and femoral neck bone mineral density (BMD) at the second examination. These 8,011 women were followed prospectively for incident hip fractures occurring after the second examination, which were confirmed by review of x-ray films. RESULTS: During an average of 5.2 years after the second examination, 236 (2.9%) women experienced hip fractures. Similar associations were observed between hip fracture risk and all measures of body size including total body weight, percent weight change since age 25, hip girth, lean mass, fat mass, percent body fat, body mass index, and modified body mass index. Women with smaller body size had a higher risk of subsequent hip fracture compared with those with larger body size, while women with average and larger body sizes shared similarly lower risks of subsequent hip fracture. For example, the incidence rate of hip fracture was 9.35 per 1000 woman-years in women in the lowest quartile of total weight compared with 4.63 per 1000 woman-years in women in the highest quartile of total weight (age-adjusted relative risk 1.93, 95% confidence interval (CI) 1.34 to 2.80), while rates of hip fracture among women in the second and third quartiles of total weight (5.22 and 4.32 per 1000 woman-years, respectively) were not significantly different from the rate among women in the highest quartile ( P > 0.64). The increased risk of hip fracture among women of smaller body size remained after further adjustment for additional potential confounding factors including height at age 25, smoking status, physical activity, health status, estrogen use, and diuretic use. After further adjustment for femoral neck BMD, women with smaller body size were no longer at significantly increased risk of hip fracture compared with those with larger body size. For example, after adjustment for height at age 25, smoking status, physical activity, health status, estrogen use, and diuretic use, thin women had a 2.5-fold increase in the risk of hip fracture (multivariate relative risk 2.51, 95% CI 1.69 to 3.73) compared with the referent group composed of the heaviest women. After further adjustment for femoral neck BMD, the multivariate relative risk of hip fracture among thin women compared to heaviest women was 0.98 (95% CI, 0.64 to 1.50). CONCLUSION: Older women with smaller body size are at increased risk of hip fracture. This effect is because of lower hip BMD in women with smaller body size. Assessment of body size for prediction of hip fracture risk can be accomplished by measuring total body weight.
Acute and chronic toxicities of arsenic(III) to fathead minnows, flagfish, daphnids, and an amphipod

Acute and chronic toxicities of arsenic (III) (As) to four species of freshwater organisms were determined. All tests were flow-through exposures except the daphnid (Daphnia magna) tests which were static concentration renewal exposures. Acute exposures of fathead minnows (Pimephales promelas), flagfish (Jordanella floridae), and an amphipod (Gammarus pseudolimnaeus) to As resulted in 96-hr LC50 or EC50 estimates of 14,100, 14,400, and 874 μg/L, respectively. Daphnids were exposed to As with and without food resulting in 96-hr EC50 estimates of 4,340 and 1,500 μg/L, respectively. Chronic exposures of 28 to 31 days duration were made for fathead minnows, flagfish, and daphnids. The chronic limit ranges (highest tested exposure concentration having no adverse effect and the lowest tested exposure concentration having an adverse effect) based upon the most sensitive measured parameters of body length and wet weight were 2,130 to 4,300 μg/L for fathead minnows and 2,130 to 4,120 μg/L for flagfish. Daphnids had chronic limits of 633 to 1,320 μg/L based upon survival and the measured parameters of reproduction and body length. Calculation of an acute test/chronic test ratio for fathead minnows, flagfish, and daphnids (fed and unfed) resulted in a range of values from 1.64 to 4.80.
A communication-optimal framework for contracting distributed tensors

Tensor contractions are extremely compute intensive generalized matrix multiplication operations encountered in many computational science fields, such as quantum chemistry and nuclear physics. Unlike distributed matrix multiplication, which has been extensively studied, limited work has been done in understanding distributed tensor contractions. In this paper, we characterize distributed tensor contraction algorithms on torus networks. We develop a framework with three fundamental communication operators to generate communication-efficient contraction algorithms for arbitrary tensor contractions. We show that for a given amount of memory per processor, the framework is communication optimal for all tensor contractions. We demonstrate performance and scalability of the framework on up to 262,144 cores on a Blue Gene/Q supercomputer.
Resonance processes and nuclear excitation in muonic 205Tl

Abstract The L and K X-rays of muonic 205Tl have been measured with an enriched (99.8 %) 205Tl target. Two sets of resonance processes were included in the analysis, which led to satisfactory fits to the experimental spectra, and explain the anomalous intensity ratios between the fine structure components of the muonic L and K X-rays. At the same time, the M1 hyperfine structure constants, which show the finite distribution of the nuclear M1 moment, were determined. Also determined were the static nuclear E2 and M1 moments of the excited states.
Goats Don't Wear Coats: An Examination of Semantic Interference in Rhyming Assessments of Reading Readiness for English Language Learners

Abstract Rhyming tests have historically been used in the education system to assess reading readiness. English language learners (ELLs) have consistently scored poorly on these assessment tools. The current article examines a possible reason for this poor performance by ELLs. Specifically, the authors examined the relationship between semantic associations of visual images and performance on rhyming assessments for ELLs. Two groups of students, native English speakers and native Spanish speakers, were tested using a typical rhyming assessment tool. As expected, it was found that the native English speakers outperformed the native Spanish speakers. An analysis of the native Spanish speakers' errors revealed semantic interference. Educational implications of these findings are discussed.
Trust as sensemaking: the microdynamics of trust in interfirm alliances

Although contracts are an important part of any interorganizational relationship, it is generally accepted that informal understanding, based on trust, may prove even more powerful than contracts in assuring a successful relationship. This study presents an empirical test of a theory of trust creation in economic exchange. The paper explores the theoretical proposition that trust creation may be viewed as a process of sensemaking in which small cues are enlarged through the incremental accumulation of evidence. Interview and questionnaire data obtained on strategic partnerships from chief executive officers and senior management in the biotechnology, pharmaceutical, and medical equipment manufacturing companies in North America showed that trust building in partnerships may be a sort of self-fulfilling prophecy in which initial expectations positively impact behavior and trust building. The results also show that there may be some optimal level of expectations. Both too low and too high an expectation were counterproductive to trust building.
Characterization and Potential Utilization of the Asphalt Ridge Tar Sand Bitumen I. Gas Chromatography - Mass Spectrometry and Pyrolysis-Mass Spectrometry Analyses

ABSTRACT The native Asphalt Ridge bitumen was separated into several boiling range fractions for detailed analysis and characterization. The lighter fraction (477–617 K) was evaluated for use as an aviation turbine fuel and the residue (>617 K) was evaluated for use as an asphalt. The 477–617 K fraction appeared to meet most of the specifications for high density aviation turbine fuels. The 617 K plus residue from the Asphalt Ridge bitumen can be classified as a viscosity grade AC-30 asphalt. Several physical properties were also measured to evaluate the potential of the 477–617 K fraction as high density-energy aviation turbine fuel after mild hydrotreating. The detailed structure of the low molecular weight fractions of the Asphalt Ridge bitumen (477–617 K and 617–711 K) was determined by combined gas chromatography and mass spectrometry. Additional insight regarding the chemical structure of the bitumen was also obtained by Fourier transform infrared analysis. The tentative identification of saturated ...
Transition into a magnetic state without magnetic scattering in a rare earth system: CeAl3

Abstract Susceptibility measurements on CeAl 3 down to 0.5 K show both the absence of magnetic ordering and a reduced effective moment such as found in dilute Kondo alloys. The resistance decreases a factor of 30 below the maximum at T = 37 K and the magneto resistance which is negative above 0.5 K apparently becomes positive for T
Stabilization of nonlinear time-varying systems: a control lyapunov function approach

This paper presents a control Lyapunov function approach to the global stabilization problem for general nonlinear and time-varying systems. Explicit stabilizing feedback control laws are proposed based on the method of control Lyapunov functions and Sontag's universal formula.
Pattern regulation during regeneration of limb stumps bearing partial circumferences of flank skin in the newt, Notophthalmus viridescens

The regenerative ability of limb stumps bearing partial circumferences of flank skin was tested in the newt, Notophthalmus viridescens. Skin dorsal to the lateral line of the flank was removed and used to replace 1/4, 1/2, or 3/4 of the skin of the upper forelimb. Grafts were placed at anterior, posterior, dorsal, or ventral positions relative to the axes of the limb. After 30 days of graft healing the limbs were amputated through the grafts and were permitted to regenerate for 60 days. Limb stumps bearing 1/4 circumference of flank skin regenerated complete limbs in 85% of the experimental cases. After 1/2 circumference of limb skin was replaced, 57% regenerated complete limbs. When 3/4 of the limb skin was replaced by flank skin, 29% regenerated complete limbs. Only 2% of experimental limbs bearing a full circumference of flank skin regenerated complete limbs in an earlier study [Tank, P.W. (1984) J. Exp. Zool., 229:143–153]. The greatest effect on pattern formation was observed when flank skin grafts were placed at the ventral position of the limb stump regardless of graft size. These results are discussed in light of the idea that short-range cellular interactions between limb cells are essential for pattern formation during limb regeneration.
Analysis of spatial variations in the effectiveness of graduated driver's licensing (GDL) program in the state of Michigan.

Abstract Injury resulting from motor vehicle crashes is the leading cause of death among teenagers in the US. Few programs or policies have been found to be effective in reducing the risk of fatal car crashes for young novice drivers. One effective policy that has been widely implemented is Graduated Driver Licensing (GDL). Published articles have mostly reported on the temporal effectiveness of GDL in the US. This article reports on the development of spatial statistical modeling approaches to evaluate and compare the effectiveness of GDL policy across eighty-three counties in the state of Michigan. Data were gathered from several publicly available databases, including the US Fatality Analysis Reporting System (FARS), US Census Bureau, US Bureau of Labor Statistics, and US Department of Agriculture. To account for spatial dependence among crash counts from adjacent counties we invoke spatial random effects, which we provide with a Conditionally AutoRegressive (CAR) prior. Our analysis confirms previous findings that GDL in Michigan is an effective policy that significantly reduces the risk of fatal car crashes among novice teenage drivers. In addition, it indicates that rurality is an important contextual variable associated with spatial differences in GDL effectiveness across the state of Michigan. Finally, our findings provide information that can be used to strengthen GDL policy and its implementation to further enhance teenage-driver safety.
Model compounds based on poly(p-phenylenevinyleneborane) and terthiophene: Investigating the p–n junction in diblock copolymers

Abstract Conjugated block copolymers represent a class of materials with potential applications in electronics and optoelectronics. Three block copolymer model compounds were made by first synthesizing 5-ethynyl-2,2′:5′,2″-terthiophene, 5-(2-propynyl)-2,2′:5′,2″-terthiophene and 5-(3-butynyl)-2,2′:5′,2″-terthiophene and then performing hydroboration polymerization from the alkyne of the terthiophene. The impact of the connectivity between the polymer blocks of these compounds was investigated. Theoretical and experimental studies indicated that charge transfer was occurring within the all-conjugated copolymer model compound, and that electronic coupling decreased with increasing length of the linking bridge between the n-type and p-type materials. Preliminary efforts to synthesize the related regioregular poly(3-hexylthiophene) all-conjugated diblock copolymer and use this material as the active layer in photovoltaic cells are discussed.
Standby power reduction using dynamic voltage scaling and canary flip-flop structures

Lowering V/sub DD/ during standby mode reduces power by decreasing both voltage and current. Analysis of flip-flop structures shows how low the voltage can scale before destroying the state information. Measurements of a 0.13-/spl mu/m, dual-V/sub T/ test chip show that reducing V/sub DD/ to near the point where state is lost gives the best power savings. We show that "canary" flip-flops provide a mechanism for observing the proximity to failure for the flip-flops. The canary flip-flops enable closed-loop standby voltage scaling for achieving savings near the optimum. This approach potentially provides over 2/spl times/ higher savings than an optimal open-loop approach without loss of state.
Vegetation canopy reflectance modeling—recent developments and remote sensing perspectives∗

The modeling of the directional reflectance of vegetation canopies and vegetation‐covered surfaces has been a highly active field in remote sensing within the past decade. Recent developments have refined physical models of directional reflectance; added coupled atmospheric models; included invertible models; and produced new, semiempirical models. Although models are well‐formulated, more validation datasets are needed. For the EOS era, invertible models that provide useful information for global change studies are most desirable.
A comparative analysis of spectral exponent estimation techniques for 1/fβ processes with applications to the analysis of stride interval time series

Background The time evolution and complex interactions of many nonlinear systems, such as in the human body, result in fractal types of parameter outcomes that exhibit self similarity over long time scales by a power law in the frequency spectrum S(f) = 1/fβ. The scaling exponent β is thus often interpreted as a “biomarker” of relative health and decline.
Understanding supplier selection practices: Differences between u.s. And korean executives

Over the past decades, U.S. firms have increasingly explored strategic supply chain partnerships with Asian firms. Although shaken by the financial crises in 1997, Asian firms also continue to make significant investment in the U.S. and develop strategic supply chain partnership with U.S. firms. These trends have prompted academic researchers to start focusing on global supply chain management prac-tices. One important domain of supply chain management is the selection of sup-pliers. This research examines the differences in supplier selection practices between U.S. and Asian (in particular, Korean) executives. The results provide important implications for both U.S. and Korean firms to successfully manage global supply chain management. � 2001 John Wiley & Sons, Inc.
BRG1-mediated immune tolerance: facilitation of Treg activation and partial independence of chromatin remodelling

Treg activation in response to environmental cues is necessary for regulatory T cells (Tregs) to suppress inflammation, but little is known about the transcription mechanisms controlling Treg activation. We report that despite the known proinflammatory role of the chromatin-remodelling factor BRG1 in CD4 cells, deleting Brg1 in all αβ T cell lineages led to fatal inflammation, which reflected essential roles of BRG1 in Tregs. Brg1 deletion impaired Treg activation, concomitant with the onset of the inflammation. Remarkably, as the inflammation progressed, Tregs became increasingly activated, but the activation levels could not catch up with the severity of inflammation. In vitro assays indicate that BRG1 regulates a subset of TCR target genes including multiple chemokine receptor genes. Finally, using a method that can create littermates bearing either a tissue-specific point mutation or deletion, we found the BRG1 ATPase activity partially dispensable for BRG1 function. Collectively, these data suggest that BRG1 acts in part via remodelling-independent functions to sensitize Tregs to inflammatory cues, thus allowing Tregs to promptly and effectively suppress autoimmunity.
Image analysis measurements of particle coefficient of restitution for coal gasification applications

Abstract New robust Lagrangian computational fluid dynamic (CFD) models are powerful tools that can be used to study the behavior of a diverse population of coal particle sizes, densities, and mineral compositions in entrained gasifiers. By using this approach, the responses of the particles impacting the wall were characterized over a range of velocities (1 to 8 m/s) and incident angles (90 to 20°). Within CFD models, the kinematic coefficient of restitution is the boundary condition defining the particle wall behavior. Four surfaces were studied to simulate the physical conditions of different entrained-flow gasification particle–surface collision scenarios: 1) a flat metal plate 2) a low viscosity silicon adhesive, 3) a high viscosity silicon adhesive, and 4) adhered particles on a flat metal plate with Young's modulus of elasticity ranging from 0.9 to 190 GPa. Entrained flow and drop experiments were conducted with granular coke particles, polyethylene beads and polystyrene pellets. The particle normal and tangential coefficients of restitution were measured using high speed imaging and particle tracking. The measured coefficients of restitution were observed to have a strong dependence on the rebound angles for most of the data. Suitable algebraic expressions for the normal and the tangential component of the coefficient of restitution were developed based upon ANOVA analysis. These expressions quantify the effect of normalized Young's modulus, particle equancy, and relative velocity on the coefficient of restitution. The coefficient of restitution did not have a strong dependence on the particle velocity over the range considered as long as the velocity was above the critical velocity. However, strong correlations were found between the degree of equancy of the particles and the mean coefficient of restitution such that the coefficient of restitution decreased for smaller particle equancies. It was concluded that the degree of equancy and the normalized Young's modulus should be considered in applications such as gasification and other cases involving the impact of non-spherical particles and complex surfaces. Sliding was observed when particles impacted on oblique surfaces; however, the resulting effects were within the range of measurement uncertainties.
Learning and data clustering with an RBF-based spiking neuron network

A spiking neuron is a simplified model of the biological neuron as the input, output, and internal representation of information based on the relative timing of individual spikes, and is closely related to the biological network. We extend the learning algorithms with spiking neurons developed by earlier workers. These algorithms explicitly concerned a single pair of pre- and postsynaptic spikes and cannot be applied to situations involving multiple spikes arriving at the same synapse. The aim of the algorithm presented here is to achieve synaptic plasticity by using relative timing between single pre- and postsynaptic spikes and therefore to improve the performance on large datasets. The learning algorithm is based on spike timing-dependent synaptic plasticity, which uses exact spike timing to optimize the information stream through the neural network as well as to enforce the competition between neurons during unsupervised Hebbian learning. We demonstrate the performance of the proposed spiking neuron m...
Kerr effect as evidence of gyrotropic order in the cuprates

The Kerr effect can arise in a time-reversal invariant dissipative medium that is "gyrotropic", i.e. one that breaks inversion ($\mathcal I$) and all mirror symmetries. Examples of such systems include electron analogs of cholesteric liquid crystals, and their descendants, such as systems with chiral charge ordering. We present arguments that the striking Kerr onset seen in the pseudogap phase of a large number of cuprate high temperature superconductors is evidence of chiral charge ordering. We discuss additional experimental consequences of a phase transition to a gyrotropic state, including the appearance of a zero field Nernst effect.
Molecular Dynamics Simulations of Conformational Change in EPAC

Recent work from the Bos group has shown that the exchange protein activated by cAMP (EPAC), binds a single cAMP to allosterically regulate an ionic lock inducing a large conformational change and opening a binding site for the GTPases Rap1 or Rap2. Their x-ray structures of EPAC consist of two large regions with five domains. An ionic lock is defined by R886 and D883 of CDC25-HD and E332, D307 and Q303 of the CNB. When this lock is released the hinge region swings closer to the CNB domain creating a 45-Angstrom shift in the structural region. Mutations in this ionic lock (R886A) in EPAC produce a reduction in GEF activity, rather than an increase. This unexpected result is at odds with a simple picture of a direct tradeoff between cAMP binding energy and ionic lock release. DIMS trajectories of the conformational transition allow us to compute the energetic role of the mutation in entropy-enthalpy compensation and elucidate the allosteric communication pathways that are modulated by the mutation. Reference trajectories of the wild-type and the mutation (R886A) in the inactive and active states give us additional insights into the nature of the changes.View Large Image | View Hi-Res Image | Download PowerPoint Slide
Brainstem auditory evoked potentials in atypical facial neuralgia

Atypical facial neuralgia is an ill-defined syndrome of obscure etiology characterized by chronic facial pain. The diagnosis is one of exclusion, made only after carefully ruling out a variety of conditions that may cause orofacial pain. The present study detected brainstem abnormalities on the side of the facial pain through examination of brainstem auditory evoked potentials in two out of 12 patients who were clinically diagnosed as having atypical facial neuralgia. The recording of brainstem auditory evoked potentials provides a simple, well-standardized, noninvasive test that may be of value in the investigation of patients who have chronic facial pain.
Quantum physics: A strong hybrid couple

A single atom in an optical cavity is shown to interact strongly with an incoming photon and to switch the photon's state. This finding opens up a path towards optical quantum computation and quantum networks. See Letters p.237 & p.241 The development of a quantum gate between a flying optical photonic qubit (polarization) and a single trapped atomic qubit (spin) has been a long-standing goal in quantum information science. Such gates are required both for quantum computation to be scaled to a large number of qubits and for quantum communication to be scaled to long distances. Now two groups, working independently, report the successful implementation of such gates. Gerhard Rempe and colleagues demonstrate a quantum gate between a laser-trapped atomic qubit and a single photon, where the polarization of the photon is flipped depending exactly on the spin state of the atom. Mikhail Lukin and co-workers describe a similar achievement — a quantum gate effect between a single atom trapped near a photonic crystal and a single photon.
Flight dynamics simulation of lightcraft propelled by laser ablation

A six degree-of-freedom (DOF) dynamic model was developed to provide insight into the flight behavior of Type 200 Lightcraft, and to serve as a research tool for developing future engine-vehicle configurations for laser launching of nano-satellites (1-10 kg). Accurate engine, beam, and aerodynamics models are included to improve the predictive capability of the 6-DOF code. The aerodynamic forces of lift, drag, and aerodynamic pitching moment were derived from Fluent ® computational fluid dynamics predictions, and calibrated against limited existing wind tunnel data. To facilitate 6-DOF model validation, simulation results are compared with video analysis of flights under comparable conditions. Despite current limitations of the 6-DOF model, the results compared well with experimental flight trajectory data.
Work in progress: Engaging new PIs using an electronic mentoring system

Success as a Principal Investigator (PI) of a National Science Foundation (NSF)-funded project requires both project management and change leadership skills, disciplinary knowledge, and familiarity with the project itself. Because gaining the skills of management and leadership involves either first-hand or vicarious experience, new PIs might struggle to find the best course of action when facing a difficult situation. While individual mentoring could enable new and prospective PIs to acquire these skills, arranging a mentor for all new PIs is not feasible. In addition, prior work has indicated a preference in faculty for gaining knowledge informally (e.g., using case studies) from mentors who have experienced similar situations rather than in more formally assigned partnerships. Thus, we seek to understand whether a many-to-many electronic mentoring website is an effective method to aid new and prospective PIs in a range of NSF programs in developing project and change management skills.
Affinity chromatographic examination of a retention model for macromolecules.

Plots of log k′ vs. log (1/[mobile phase modifier]) were made for a monovalent and a divalent solute using affinity chromatography. Some of the plots were curved and all exhibited slopes (Z values) of less than the theoretical integer values. It was shown that this was an expected result when lower forms of the solute were present, e.g., a divalent solute adsorbed monovalently.
Is caffeine use during pregnancy really unsafe

Althoughthe authors state that their work overcomes the deﬁciencies ofmany previous studies looking at the impact of caffeine con-sumption on the risk of miscarriage, we respectfully disagree.Infact,theirstudysuffersfrommanyofthesameproblemsthathave plagued other work in this area.Althoughtheauthorsrepeatedlyrefertotheirstudyasapro-spective cohort study, reporting of caffeine consumption fromLMP to interview was retrospective. Further, 59% of thewomen who miscarried were interviewed after their miscar-riage,raisingconcernsofrecallbias.Althoughtheauthorsstatein the
Determination of the Time Constant of Fine-Wire Thermocouples for Compensated Temperature Measurements in Premixed Turbulent Flames

Abstract A new method for the determination of thermocouple time constants is described, which reproduces the large temperature differences between the thermocouple junction and ambient fluid that occur in premixed turbulent flame applications. Time constants measured while the thermocouple is both heating and cooling, as well as the dependency of the time constant on velocity and temperature, are reported. Velocities are varied from 0.6 to 5.5 ms-1, and junction temperatures range from 700K to ISOOK while heating and from 400K to llooK while cooling. Temperature differences between the thermocouple junction and ambient fluid up to 800K are achieved. Radiation losses from the junction are accounted for. Predicted time constants based on commonly used correlations for heat transfer from a cylinder in cross-flow are compared to the data, and it is suggested that free molecular flow effects are partially responsible for the systematic deviation of the data from the theoretical predictions.
Strip Type Components for 2000 Megacycle Receiver Head-End

Recent experimental work has evolved some components using air-spaced strip type transmission line that have been used successfully in connection with a variable attenuator, cavity and crystal mixer. Bandwidth, VSWR, and NF measurements are comparable with a commercial receiver head-end presently in use. The asymmetric air-spaced strip-above-ground transmission line used results in a simple configuration for coupling the line to the cavity. It also facilitates the application of a variable attenuator using a ferrite slab of high attenuation per unit length and having good VSWR properties.
On `strange' properties of some symmetric inhomogeneities

The paper presents an analysis of elasticity problems involving a single inhomogeneity which possesses certain types of symmetries. As observed earlier, isotropic problems of that kind exhibit some ‘strange’ and remarkable properties. Under the action of uniform far-field stresses, the averages of the fields inside the inhomogeneities preserve the structure of the far-field loads. Here, it is shown that these properties are exhibited for a wider class of problems, which include anisotropic and non-uniform materials subjected to either far-field loads or constant transformational strains within the inhomogeneity. The proposed modified Eshelby technique facilitates a straightforward analysis of these problems, which is based entirely on the assumed symmetry. It is also shown that some remarkable properties of symmetric inhomogeneities discovered here are related to the so-called ‘strange’ properties of the Eshelby inclusions extensively covered in the literature. Some implications of these findings are discussed.
General linear contrasts on latent variable means: structural equation hypothesis tests for multivariate clinical trials.

Structural equation models articulate the assumed measurement and causal relations among variables, imposing discipline on otherwise unstructured and redundant associations that arise in correlational studies. Biomedical research has eschewed such methods, relying on the generally superior causal inference afforded by randomized controlled trials. Increasingly, however, clinical trials incorporate numerous covariates that are measured but unmanipulated. Most clinical trials now also include multiple correlated endpoints, which can generate ambiguous outcome patterns refractory to simple statistical analysis and interpretation. Modern clinical trials are really multivariate longitudinal studies with at best a component of randomized control; as such, structural equation approaches can add rigour and clarity. The analysis of latent variance (LANOVA) conception combines structural equation and experimental analysis of variance legacies. It allows, for any design that can be decomposed into between-group and within-person models, tests on latent means (that is, the means of the unobserved factors) that are directly analogous to their analysis of variance counterparts. LANOVA variables are either outcomes (which may have a time structure), varying covariates (which may have a time structure), or background covariates (which are static). Allowable causal relations are set-recursive: background covariates can affect all other variables; varying covariates can affect current outcomes and later outcomes and covariates; outcomes can affect only later outcomes. All standard ANOVA and ANCOVA hypotheses can then be tested by proper restrictions among the means and intercepts of these latent variables. Structural equation modelling programs can be used to estimate the models and test the hypotheses. I demonstrate the approach by expressing and testing hypotheses appropriate for two clinical studies that evaluate patient-reported outcomes in populations with solid and haematological malignancies.
The Power of Policy Change, Federal Collaboration, and State Coordination in Healthcare-Associated Infection Prevention

Policymakers have prioritized the prevention of healthcare-associated infections (HAIs) as a double-win that can both improve health outcomes and reduce healthcare costs. In the past few years, state and federal policymakers have developed policies to improve coordination and promote transparency and prevention. At the federal level, congressional oversight, policy directives, and targeted funding have helped focus national HAI prevention efforts through the Department of Health and Human Services Action Plan to Prevent Healthcare-Associated Infections. The development of this action plan and the collaboration of its implementing agencies-the Centers for Disease Control and Prevention, the Centers for Medicare and Medicaid Services, and the Agency for Healthcare Research and Quality-have heightened nationwide awareness of HAIs and their preventability, and provided an infrastructure and tools to reduce HAIs. State policymakers have also acted to promote local transparency and tailor prevention efforts to local needs. The collaboration and action generated by these state and federal efforts have helped accelerate HAI prevention across the United States.
Holistic power analysis of implementation alternatives for a very large scale synthesis array with phased array stations

The Square Kilometre Array (SKA) will be the largest radio telescope in the world, generating data at Pb/s rates. Real-time processing will require 10 18 compute operations per second and system operating costs will be dominated by energy consumption. In this paper we explore design options for the aperture array of the first SKA construction phase and provide lower bounds on their power consumption. We analyze the system's components from the antenna front-end to the central signal processor and identify the main power consumers. We compare ASIC-based and FPGA-based data processing pipelines and show that ASICs can lead to 1.6 to 4 times more power efficiency.
Hydraulic Design of a Longitudinal Culvert for Lock Filling and Emptying Systems

The U.S. Army Corps of Engineers is planning navigation improvements for many projects to meet predicted increases in tow traffic. Some of these improvements include the addition or replacement of ...
The Pathophysiology of Fragile X Syndrome

AbstractFragile X syndrome is the most common form of inherited mental retardation. The disorder is mainly caused by the expansion of the trinucleotide sequence CGG located in the 5′ UTR of the FMR1 gene on the X chromosome. The abnormal expansion of this triplet leads to hypermethylation and consequent silencing of the FMR1 gene. Thus, the absence of the encoded protein (FMRP) is the basis for the phenotype. FMRP is a selective RNA-binding protein that associates with polyribosomes and acts as a negative regulator of translation. FMRP appears to play an important role in synaptic plasticity by regulating the synthesis of proteins encoded by certain mRNAs localized in the dendrite. An advancing understanding of the pathophysiology of this disorder has led to promising strategies for pharmacologic interventions.
Effects of a Summer Program on the Social Self-Concepts of Gifted Adolescents:

This study investigates the change in social self-concept among adolescents participating in a summer program for the gifted. Participants include 140 gifted students who had completed the 7th through 10th grade during the previous academic year. Social self-concept was measured at the beginning and end of the summer camp using the same-sex peer relations and the opposite-sex peer relations subscales of the Self-Description Questionnaire II (Marsh, 1990). Results indicate both males and females experienced an increase in their perceived same-sex peer relations and their perceived opposite-sex peer relations over the course of the summer program. Conclusions and implications for education policy are discussed.