cssi/SciSciGPT-SciSciNet huggingface dataset:
Differential-Geometric-Control Formulation of Flapping Flight Multi-body Dynamics

Flapping flight dynamics is quite an intricate problem that is typically represented by a multi-body, multi-scale, nonlinear, time-varying dynamical system. The unduly simple modeling and analysis of such dynamics in the literature has long obstructed the discovery of some of the fascinating mechanisms that these flapping-wing creatures possess. Neglecting the wing inertial effects and directly averaging the dynamics over the flapping cycle are two major simplifying assumptions that have been extensively used in the literature of flapping flight balance and stability analysis. By relaxing these assumptions and formulating the multi-body dynamics of flapping-wing micro-air-vehicles in a differential-geometric-control framework, we reveal a vibrational stabilization mechanism that greatly contributes to the body pitch stabilization. The discovered vibrational stabilization mechanism is induced by the interaction between the fast oscillatory aerodynamic loads on the wings and the relatively slow body motion. This stabilization mechanism provides an artificial stiffness (i.e., spring action) to the body rotation around its pitch axis. Such a spring action is similar to that of Kapitsa pendulum where the unstable inverted pendulum is stabilized through applying fast-enough periodic forcing. Such a phenomenon cannot be captured using the overly simplified modeling and analysis of flapping flight dynamics.
A Bayesian analysis for the Mann-Whitney statistic

AbstractA Bayesian analysis is developed for the Mann-Whitney (U) statistic. The analysis is focused on an Ω parameter, which is defined as the integrated proportion of the population in a generic ...
Lessons Learned from an International Infection Control Consultation in a Newly Built Hospital in Saudi Arabia

BACKGROUND A small team, consisting of a Infection Prevention/Accreditation Manager and an Infection Prevention Specialist were assigned to assist in consulting abroad with the commissioning of a new hospital in Saudi Arabia. The hospital was built from the ground up and staff had no experience with Infection Control Standards. METHODS To provide the best guidance possible, the team traveled to Saudi Arabia to work with local staff. Time was spent touring the construction site, reviewing blueprints and providing recommendations for best practices for both construction and room layouts. Education/recommendations were provided to the C-Suite Leadership to target gaps. Simultaneously, the team was working on interviewing potential candidates for the Infection Prevention role, as well as working to build up their program by drafting policies and plans. The partnership continued from afar, with weekly calls to the team in Saudi Arabia. RESULTS It was challenging to get all C-Suite leadership to understand the importance and urgency of Infection Control recommendations that were provide by the team. There were many recommendations that could result in delays in opening the hospital, which led to resistance from leadership. There were many challenges with construction companies and their knowledge and training, as well as with different requirements between our two countries. Recommendations were made for cleaning, environmental testing, and sign-off before occupancy in order to provide staff/employees with assurance and safety. CONCLUSIONS After a few years of work, we saw success but were also met with challenges. The importance of involvement with Infection Control from the early stages was crucial. Since we could not be on-site during the duration of the project, the selection of the right IP for daily work was an imperative link. Not all recommendations were followed leading up to staggered opening. Immediate attention was called to this for correction and remediation.
Analysis of Anti–Vascular Endothelial Growth Factor Injection Claims Data in US Medicare Part B Beneficiaries From 2012 to 2015

Importance The frequency of anti–vascular endothelial growth factor (VEGF) injections has grown exponentially with the introduction of bevacizumab, ranibizumab, and most recently aflibercept. The cost associated with these medications has garnered significant national attention, warranting a granular analysis of their use. Objective To analyze trends in anti-VEGF injections for US Medicare Part B beneficiaries from 2012 to 2015. Design, Setting, and Participants This observational cohort study used 2012-2015 data from the Centers for Medicare & Medicaid Services Medicare Part B Provider Utilization Files to analyze trends in intravitreal injections of anti-VEGF medications among Medicare Part B beneficiaries and their health care professionals. Main Outcomes and Measures The primary outcome measure was distribution of and change over time in the number of anti-VEGF injections performed for ranibizumab, aflibercept, and bevacizumab. Results A total of 2 574 124 intravitreal injections were performed by 3348 ophthalmologists in the outpatient setting for Medicare Part B beneficiaries during the 2015 calendar year; 100 ophthalmologists (3.0%) performed the highest volume of intravitreal injections. The total number of intravitreal injections administered in 2015 was 870 843 for aflibercept, 697 412 for ranibizumab, and 1 147 432 for bevacizumab. Ranibizumab injections decreased by 7.1% from 2012 to 2015 and bevacizumab injections decreased by 17.1%. From 2013 to 2015, aflibercept injections increased by 69.4%. The 100 ophthalmologists performing the highest volume of ranibizumab injections, as gauged by number of injections administered, accounted for 31.0% (95% CI, 30.994%-30.997%) of all ranibizumab injections nationally. The 100 ophthalmologists performing the highest volume of aflibercept injections accounted for 17.6% (95% CI, 17.638%-17.641%) of all aflibercept injections and the 100 ophthalmologists performing the highest volume of bevacizumab injections accounted for 19.6% (95% CI, 19.649%-19.653%) of all bevacizumab injections administered nationally to Medicare Part B beneficiaries. The highest number of injections per 1000 Medicare Part B beneficiaries occurred in Nebraska (aflibercept), Tennessee (ranibizumab), and South Dakota (bevacizumab). Conclusions and Relevance A total of 3.0% of ophthalmologists account for 17.6% to 31.0% of the total number of anti-VEGF injections administered nationally in the Medicare Part B population. Overall, bevacizumab and ranibizumab injections have decreased, coinciding with a 69.4% increase in aflibercept injections.
E-016 In vitro vascular model material characterization

Introduction Endovascular devices aid in the treatment of heart failure, thrombus removal, and aneurysms. To assist in the testing and development of new endovascular devices, in vitro training models are used during the proof-of-concept and prototype testing phases of product development. Although current vessel-training models cast from human vasculature are anatomically accurate, the materials often used for casting (i.e. silicones and glass) do not accurately simulate the vascular compliance (modulus), wall friction effects (lubricity), and hardness values seen in native human vasculature. Thus, more flexible and comprehensive in vitro models are needed to better understand how endovascular devices (such as coils, stents, flow diverters, flow disruptors, liquid embolics, and thrombectomy devices delivered via guide catheters, guide wires, and delivery microcatheters) physically interact with the vessel wall and corresponding tissues. Methods To address the shortcomings of commercially-available vascular flow models, materials were developed and optimized in this study to have similar mechanical properties to human tissue. To accomplish this, both donated ‘fresh’ cadaveric vascular tissues (common carotid artery) and synthetic biomimetic materials were mechanically characterized with a hybrid rheometer (DH-R 2, TA Instruments - Figure 1). Results Via the rheometer, data was collected for luminal wall friction, radial compliance, shear modulus (G*), and elastic modulus (E*). Properties of cadaveric vessels and model materials were statistically compared, and the biomaterials were tuned to closely mimic the mechanical properties of the cadaveric vasculature. The biomaterials were manufactured into flow models. 3D printing manufacturing techniques were used to obtain repeatable anatomical accuracy. Validation of the models by partnered neurointerventionalists is underway to ensure realistic catheter trackability and anatomical accuracy. Discussion The new biomimetic materials in this study were able to simulate the compliance and mechanical properties of human vasculature more closely than existing silicone, polyurethane, and glass models. The utilization of novel biomimetic materials within this in vitro vascular flow model will allow for more relevant benchtop testing of endovascular devices. These models have the potential to generate more accurate data on device performance and may reduce the need for costly in vivo studies. Disclosures M. McCue: 1; C; Brain Aneurysm Foundation Grant-2018. W. Merritt: 1; C; Brain Aneurysm Foundation Grant-2018. 5; C; Northern Arizona University. C. Settanni: 1; C; Brain Aneurysm Foundation Grant-2018. 5; C; Northern Arizona University. T. Becker: 1; C; Brain Aneurysm Foundation Grant-2018. 5; C; Northern Arizona University, Aneuvas Technologies, Inc.
Advantages of Small Incision Lenticule Extraction (SMILE) for Mass Eye and Ear Special Issue.

This review summarizes the advantages of Small-incision lenticule extraction (SMILE), including improved patient intraoperative experience, improved postoperative ocular surface, low incidence of r...
Influenza vaccination and mortality among adults with heart failure in an integrated healthcare delivery system, 2009-2018.

Influenza infection can result in decompensation or exacerbation of heart failure (HF) symptoms, hospitalization, and death. To examine the association of influenza vaccination with mortality and hospitalization during influenza and non-influenza seasons between 2009 and 2018. In this prospective, observational cohort study, we included Kaiser Permanente Southern California members with a HF diagnosis prior to September 1 each year from 2009 to 2017. The first influenza vaccination in each season (September 1 to May 31) was recorded. Vaccinated/unvaccinated patients were matched 1:1 on age, sex, and ejection fraction at the vaccination date (n-total = 74,870). Patients were followed through the end of each influenza season for all-cause mortality. Secondary outcomes included cardiovascular mortality and all-cause hospitalization. In a sensitivity analysis, we examined mortality in the non-influenza season. Influenza vaccinated vs unvaccinated patients had more comorbidities and higher healthcare utilization. After multivariable adjustment for utilization, sociodemographics, comorbidities, and medications, influenza vaccinated vs unvaccinated patients had a lower risk of all-cause mortality and cardiovascular mortality during the influenza season (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.63, 0.70 and HR 0.68, 95% CI 0.63, 0.74, respectively) but a higher risk of all-cause hospitalization (HR 1.27, 95% CI 1.21, 1.31). There was no association between influenza vaccination and all-cause or cardiovascular mortality during the non-influenza season (HR 0.99, 95% CI 0.89, 1.09 and HR 1.00, 95% CI 0.84, 1.21, respectively). Influenza vaccination in HF patients was associated with a lower risk of mortality during the influenza season. Our findings provide support for recommendations of universal influenza vaccination in patients with HF.
Shaping the City

If enacted, the Maryland Department of Planning, in consultation with the Department of Transportation, would collaborate with counties and municipalities to delineate rail-station overlay districts and to make new master plans, design guidelines and development regulations for them. The new plans and regulations would supersede existing zoning, replacing out-of-date concepts and regulations that obstruct desirable, sustainable development. Shaping the City Roger K. Lewis, Columnist Saturday, March 12, 2011; Page E08
Clinical Assessment of the Severity of Aortic Stenosis

Valvular aortic stenosis (AS) has three primary etiologies: age-related degenerative calcification, congenital bicuspid valve with superimposed calcification, and rheumatic disease. Despite the progressive histopathological changes that lead to anatomical alteration of the aortic valve apparatus, aortic stenosis has a long asymptomatic period. Eventually, AS results in predictable pathophysiologic alterations in cardiac pressures and blood flow that elicit the classic symptomatology and physical stigmata of this disease. The development of symptoms signals an abrupt worsening in prognosis. An appreciation of these pathophysiologic derangements is essential to the clinical assessment of aortic valve obstruction.
Substitution Bias and Cost of Living Variability for U.S. Demographic Groups

. Intertemporal cost of living variability is analyzed for households with differing income levels and family characteristics. These indexes are based upon the parameter estimates of a comprehensive system of expenditure equations, the quadratic expenditure system. Despite considerable differences in the group-specific share parameters as well as nonlinearities in the Engle curves for each group, little variation occurs in these indexes for several U.S. price series over the 1967–1984 time period. As a result, we find little evidence that group-specific fixed weight indexes are better cost of living approximations than a general Consumer Price Index even though all substitution bias estimates, by income and household type, are quite small.
Central tendency and variability in biological systems

In this article, the author reviews the manner in which researchers characterize data. Normality, standard deviation, mean, and other concepts related to parametric statistics are discussed in common language, with a minimum of jargon and with clinical examples.
Two-photon collisions and QCD

A critical review of the applications of QCD to low- and high-pT interactions of two photons is presented. The advantages of the two-photon high-pT tests over corresponding hadronic beam and/or target tests of QCD are given particular emphasis.
Adaptive multiscale processing for contrast enhancement

This paper introduces a novel approach for accomplishing mammographic feature analysis through overcomplete multiresolution representations. We show that efficient representations may be identified from digital mammograms within a continuum of scale space and used to enhance features of importance to mammography. Choosing analyzing functions that are well localized in both space and frequency, results in a powerful methodology for image analysis. We describe methods of contrast enhancement based on two overcomplete (redundant) multiscale representations: (1) Dyadic wavelet transform (2) (phi) -transform. Mammograms are reconstructed from transform coefficients modified at one or more levels by non-linear, logarithmic and constant scale-space weight functions. Multiscale edges identified within distinct levels of transform space provide a local support for enhancement throughout each decomposition. We demonstrate that features extracted from wavelet spaces can provide an adaptive mechanism for accomplishing local contrast enhancement. We suggest that multiscale detection and local enhancement of singularities may be effectively employed for the visualization of breast pathology without excessive noise amplification.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Proposed human stratum corneum water domain in chemical absorption

Compounds with varying physical and chemical properties may have different affinities to the stratum corneum (SC) and/or its intercellular lipids, keratin protein, and possible water domains. To better understand the mechanism of percutaneous absorption, we utilized 21 carbon-14 labeled chemicals, with wide hydrophilicity (log P = -0.05 to 6.17), and quantified their absorption/adsorption properties for a short incubation time (15 min) with regards to intact SC membrane, delipidized SC membrane and SC lipid. A facile method was developed for SC/lipid absorption, providing a more equivalent procedure and comparable data. SC lipid absorption of chemical solutes positively correlated with the octanol/water partition coefficient (log P). Differences between the percent dose of chemical absorption to intact SC and the total percent dose contributed by the protein and lipid domains suggest the possibility and significance of a water domain. Absorption rate experiments showed a longer lag time for intact SC than for delipidized SC or SC lipid, suggesting that the water domain may delay chemical binding to protein and lipid domains, and may be a factor in the resistance of many chemicals to current decontamination methods. Copyright © 2015 John Wiley & Sons, Ltd.
Corporate debt financing and earnings quality

Abstract: Our study establishes linkages between two extensively researched areas, debt financing and the quality of earnings. Debt can have a ‘positive influence’on earnings quality because managers are likely to use their accounting discretion to provide private information about the firms’ future prospects to lower financing costs. For high debt, it can also have a ‘negative influence’ on earnings quality as managers use accruals aggressively to manage earnings to avoid covenant violations. Using accruals quality as a proxy for earnings quality, we document a non-monotonic (curvilinear) relation between debt and earnings quality. The relationship is positive at low levels of debt and negative at high debt levels with an inflection point around 41%. Our results suggest that firms that rely heavily on debt financing might be willing to bear higher costs of borrowing from lower earnings quality because the benefits from avoiding potential debt covenant violations exceed the higher borrowing costs.
High-symmetry Kida flow : Time series analysis and resummation

A high-symmetry Kida flow is studied as a candidate for a finite time blowup of incompressible Euler equations. Explicit formulas for the solutions of the Euler equations, in the class of formal power series, are derived after transforming the momentum equation into a homogeneous quadratic differential equation on a nonassociative algebra. Using these formulas, the 64th order enstrophy series was evaluated. The analysis of the enstrophy singularities using Pade and quadratic approximants is discussed.
Dynamic stability of flexible cam follower systems

AbstractDynamic stability of a flexible cam-follower system is considered. The shaft-cam-follower assembly is modelled by a single degree-of-freedom system. In the analysis, transverse and rotation...
Visual fields and electroretinography following extensive photocoagulation

Twenty-four patients with proliferative or preproliferative diabetic retinopathy underwent extensive argon laser photocoagulation in one eye. Detailed central and peripheral visual-field examinations and electroretinography were performed before treatment, and at intervals after treatment. Visual field changes were as follows: (1) eight patients had only mild to moderate constriction of all isopters, (2) 11 had discrete scotomata in addition, (3) two had prominent nerve-fiber-bundle defects, (4) three had severe constriction of all isopters, save (in two) that to the largest peripheral test object. Electroretinographic b-wave amplitudes were reduced an average of 40% to white test flashes. Blue test flashes showed an even larger reduction of the rod response. This suggests the receptors in approximately 40% of the retinal area are destroyed by such extensive photocoagulation, covering predominantly that part of the retina that has the highest concentration of rods.
Structured sparse PCA to identify miRNA co-regulatory modules

This paper presents a new mathematical formulation and the corresponding algorithms for structured sparse principal component analysis (PCA). We introduce a new concept of support matrices with structured prior based on Markov Random Field (MRF). Both the support matrices and principal components are regularized by the L 1 norm to be integrated in a coupled objective function to recover the structured sparsity from the given data. Block coordinate descent and subgradient-based optimization methods are utilized to search for proper local minima for the formulated non-convex optimization problem. We implement the proposed methods to jointly analyze micro-RNA (miRNA) and gene interaction data to identify miRNA-gene co-regulatory modules (co-modules). Our preliminary experiments demonstrate that our structured sparse PCA has the potential to identify meaningful co-regulatory modules with enriched cellular functionalities.
Identification of bedforms in lower cook inlet, Alaska

Abstract The seafloor of the central part of lower Cook Inlet, Alaska, is characterized by the presence of different sizes and types of bedforms. The bedforms in the sandy sediments include straight-crested to sinuous to lunate ripples, small, medium, and large sand waves, sand ridges, sand ribbons, and sand patches. In addition, rocky and pebbly seafloor has been identified. The water depth ranges from 25 to 120 m, and surface currents average 3.8 kt (2 m/s). Bottom currents have been measured at as much as 42 cm/s at 1 m above bottom. Underwater television observations have shown that the rate of sand transport is lower than expected because small amounts of clay and organic matter appear to inhibit remobilization. Only during the last 1 to 2 h of ebb and flood stages of spring tides, and during storms, does significant transport occur. Comparison of data from high-resolution seismic profiling systems, side-scan sonar, bottom television and camera, and bottom sampling shows that bottom and bedform interpretations based solely on sonographs can be in error. Measuring the length of ‘acoustic shadows’ on sonographs to obtain bedform heights gives dimensions that are too large by factors of 3–7. Bottom television investigations revealed that the troughs between small sand waves are flat and carpeted by shell fragments. Such coarse material has a high acoustic reflectance that is not related to slope or height and can lead to false interpretations on bedform dimensions. Our observations have shown that small sand waves commonly superimposed on larger ones are slightly higher than those present on flat hard bottom but are still less than calculated from acoustic shadows. Where the bottom is rather smooth or contains elevations small enough to be masked by bathymetric ‘noise’ caused by the pitching of the vessel, sonographs typically show either small sand waves, sand ribbons, sand patches, rocks, or smooth bottom. The smooth-bottom category can vary widely from ripples to gravelly or shelly or to small rocks with biological overgrowth as verified by television observations. Our observations have clearly demonstrated the need for an integrated multi-scale observation and sampling program in order to classify the bottom characteristics and to provide quantitative data for transport calculations.
Copper-carbon cluster CuC3: structure, infrared frequencies, and isotopic scrambling.

Copper-carbon clusters, formed by dual Nd/YAG laser vaporization, have been trapped in solid Ar at 12 K and investigated by infrared spectroscopy. Density functional calculations of a number of possible molecular structures for Cu/carbon clusters have been performed, and their associated vibrational harmonic mode frequencies and dissociation energies have been determined with a 6-311++G(3df) basis set using both B3LYP and MPW1PW91 functionals. Both computations and 13 C-isotopic substitution experiments indicate that new bands observed at 1830.0 and 1250.5 cm -1 are due to the asymmetric and symmetric C=C stretching modes, respectively, in the near-linear CuC 3 (X 2 A') cluster. Photoinduced 12/13 C-isotopic scrambling in Cu 12/13 C 3 clusters has also been observed. The mechanism for the photoscrambling is shown to involve the formation of a bicyclic CuC 3 isomer.
Preserving QoS of e-commerce sites through self-tuning: a performance model approach

The Quality of Service (QoS) of e-commerce sites plays a crucial role in attracting and retaining customers. The workload experienced by these sites tends to vary in a very dynamic way. The complexity of the sites combined with the large short-terms variations of the workload calls for automated methods for site configuration. This paper describes a method for dynamically monitoring and tuning e-commerce sites so that desired QoS levels are attained. Our approach uses hill climbing techniques combined with analytic queuing models to guide the search for the best combination of configuration parameters. We validate our approach in an experimental setting by comparing the QoS levels of a TPC-W e-commerce site with and without control. We showed that under increasing loads, the controlled system meets its QoS goals, while the uncontrolled site fails to do so.
Radiation therapy for retroperitoneal sarcoma

Retroperitoneal soft-tissue sarcoma is an uncommon cancer of mesodermal origin, which is difficult to treat owing to its location and proximity to vital structures. Complete gross resection, often involving en bloc resection, is the standard of care as it represents the only treatment that improves overall survival. Unlike extremity sarcoma, retroperitoneal soft-tissue sarcoma tumor mortality is from local recurrence. Radiation therapy is the only adjuvant treatment that has improved local control in several institutional series. However, there remains no definitive prospective, randomized trial that establishes the role of adjuvant radiation versus no radiation. Owing to significant radiation morbidity with adjacent organs, especially the small bowel, there exists no consensus on radiation timing, delivery method or dosing. Recent and current protocols use preoperative external-beam radiation with or without a method of focal boost dosing. Methods of boost dosing include brachytherapy, intraoperative radiation therapy and intensity-modulated radiation therapy. Further studies are needed to definitively include radiation therapy in the standard treatment of retroperitoneal soft-tissue sarcoma and to find the optimal balance between acceptable radiation toxicity and effective local control in treatment protocols.
Comparison of several maneuvering target tracking models

The tracking of maneuvering targets is complicated by the fact that acceleration is not directly observable or measurable. Additionally, acceleration can be induced by a variety of sources including human input, autonomous guidance, or atmospheric disturbances. The approaches to tracking maneuvering targets can be divided into two categories both of which assume that the maneuver input command is unknown. One approach is to model the maneuver as a random process. The other approach assumes that the maneuver is not random and that it is either detected or estimated in real time. The random process models generally assume one of two statistical properties, either white noise or an autocorrelated noise. The multiple-model approach is generally used with the white noise model while a zero-mean, exponentially correlated acceleration approach is used with the autocorrelated noise model. The nonrandom approach uses maneuver detection to correct the state estimate or a variable dimension filter to augment the state estimate with an extra state component during a detected maneuver. Another issue with the tracking of maneuvering target is whether to perform the Kalman filter in Polar or Cartesian coordinates. This paper will examine and compare several exponentially correlated acceleration approaches in both Polar and Cartesian coordinates for accuracy and computational complexity. They include the Singer model in both Polar and Cartesian coordinates, the Singer model in Polar coordinates converted to Cartesian coordinates, Helferty's third order rational approximation of the Singer model and the Bar-Shalom and Fortmann model. This paper shows that these models all provide very accurate position estimates with only minor differences in velocity estimates and compares the computational complexity of the models.
Evaluation of postresuscitation left ventricular global and segmental function by radionuclide ventriculography in sudden coronary death survivors of prehospital cardiac arrest: Correlation to subsequent short-term prognosis

Abstract Previous data have shown that patients with significant left ventricular (LV) dysfunction, marked abnormalities in resting hemodynamics, and multiple vessel coronary artery disease (CAD) are at increased risk for sudden cardiac death. However, in-hospital assessment of ventricular function in the early postresuscitation period of out-of-hospital cardiac arrest has not been evaluated and related to short-term outcome. By using bedside radionuclide ventriculography (RNV) we evaluated LV ejection fraction (LVEF) and wall motion in 36 nonconsecutive patients within 24 hours of their episode of out-of-hospital cardiac arrest. There were 24 men and 12 women with mean age of 62.3 years (range 21 to 85 years). Total mortality of the entire group was 38.8% at 4 weeks. Eighteen patients had LVEF 0.30. Mortality in the low LVEF group was 55.5% at 4 weeks versus 22.2% in patients with LVEF > 0.30 ( p p
Changes in Bluegill, Black Crappie, and Yellow Perch Populations in Wisconsin during 1967–1991

Abstract A common perception among fisheries managers is that the mean size and number of fish within populations has decreased over time. We examined changes in size of bluegills Lepomis macrochirus, black crappies Pomoxis nigromaculatus and yellow perch Perca flavescens in fyke net samples during 1967–1991 to determine changes in size of fish and in creel surveys during 1980–1991 to determine changes in size of fish harvested and total angler catch and harvest. Mean size and proportion of large bluegills and yellow perch in fyke net samples decreased throughout the sample period. Total catch and harvest of bluegills, black crappies, and yellow perch decreased significantly during 1980–1991. Although mean size of bluegills and yellow perch harvested did not change during 1980–1991, the proportion of large bluegills harvested decreased and the proportion of large black crappies harvested increased. We conclude there was a small, but significant reduction in the size of bluegills and yellow perch in the po...
Assessing genotypic variability of cowpea (Vigna unguiculata [L.] Walp.) to current and projected ultraviolet-B radiation.

Abstract The current and projected terrestrial ultraviolet-B (UV-B) radiation affects growth and reproductive potential of many crops. Cowpea ( Vigna unguiculata [L.] Walp.), mostly grown in tropical and sub-tropical regions may already be experiencing critical doses of UV-B radiation due to a thinner ozone column in those regions. Better understanding of genotypic variability to UV-B radiation is a prerequisite in developing genotypes tolerant to current and projected changes in UV-B radiation. An experiment was conducted in sunlit, controlled environment chambers to evaluate the sensitivity of cowpea genotypes to a range of UV-B radiation levels. Six cowpea genotypes [Prima, California Blackeye (CB)-5, CB-27, CB-46, Mississippi Pinkeye (MPE) and UCR-193], representing origin of different geographical locations, were grown at 30/22 °C day/night temperature from seeding to maturity. Four biologically effective ultraviolet-B radiation treatments of 0 (control), 5, 10, and 15 kJ m −2 d −1 were imposed from eight days after emergence to maturity. Significant genotypic variability was observed for UV-B responsiveness of eighteen plant attributes measured. The magnitude of the sensitivity to UV-B radiation also varied among cowpea genotypes. Plants from all genotypes grown in elevated UV-B radiation were significantly shorter in stem and flower lengths and exhibited lower seed yields compared to the plants grown under control conditions. Most of the vegetative parameters, in general, showed a positive response to UV-B, whereas the reproductive parameters exhibited a negative response showing the importance of reproductive characters in determining tolerance of cultivars to UV-B radiation. However, all cultivars, except MPE, behaved negatively to UV-B when a combined response index was derived across parameters and UV-B levels. Based on the combined total stress response index (C-TSRI) calculated as sum of individual vegetative, physiological and reproductive component responses over the UV-B treatments, the genotypes were classified as tolerant (MPE), intermediate (CB-5, CB-46 and UCR-193) and sensitive (CB-27 and Prima) to UV-B radiation. The differences in sensitivity among the cowpea genotypes emphasize the need for selecting or developing genotypes with tolerance to current and projected UV-B radiation.
Experimental Methods in Quadratic Programming

This paper considers a class of algorithms for solving quadratic programming problems. An attempt is made to rank the various procedures. Computational results are given and a discussion of the results is presented.
Dual-function EUV multilayer mirrors for the IMAGE mission

We have developed a new family of EUV multilayer mirror coatings using uranium. Using this approach we have coated a set of six mirrors for the EUV Imager, a component of the IMAGE mission. This mission is a Medium Explorer (MIDEX) program, which is scheduled for launch early in 2000. The EUV Imager will study the distribution of He+ in the Earth's plasmasphere by detecting its resonantly scattered emission at 30.4 nm (41 eV) and will produce images of the structure and dynamics of the cold plasma on a global scale. There is, however, a bright emission at 58.4 nm (21 eV), which comes from neutral helium in the earth's ionosphere which also must be blocked. These photons are at too high an energy to filter with aluminum but at too low an energy to have negligible reflectance from most materials commonly used in EUV mirrors. Thus, a multilayer system which satisfied two optical functions, high reflectance (greater than 20%) at 41 eV and low reflectance (less than 2%) at 21 eV, were designed and successfully fabricated. Such mirrors with dual optical functions in the soft x-ray/EUV had not previously been designed or built. These specifications were particularly challenging because many materials have higher single layer reflectances at 58.4 nm than at 30.4 nm. Essentially, the mirror must have low reflectance at 21 eV without loss of reflection at 30.4 nm. This was accomplished. The top part of the multilayer, which reflects well at 30.4 nm, also acts as antireflection layers at 58.4 nm. In the past, multilayers usually have consisted of periodic bilayers. We have explored the use of a periodic mirrors in place of the standard periodic designs. Along the way we have created the computational tools, which include genetic algorithms, to optimize selection of materials and thicknesses. We are currently in the process of building up an EUV characterization system and developing a general way of measuring the optical constants of air-sensitive thin films. We discuss the other material and fabrication challenges faced, which include: (1) The high absorption of almost everything in the EUV. This means that only a few interfaces in a multilayer will contribute to its reflectance. (2) Surface contamination and corrosion. (3) The deposition on flight mirrors that are highly curved (f equals 0.8).© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Consistent surgeon evaluations of three-dimensional rendering of PET/CT scans of the abdomen of a patient with a ductal pancreatic mass.

Two-dimensional (2D) positron emission tomography (PET) and computed tomography (CT) are used for diagnosis and evaluation of cancer patients, requiring surgeons to look through multiple planar images to comprehend the tumor and surrounding tissues. We hypothesized that experienced surgeons would consistently evaluate three-dimensional (3D) presentation of CT images overlaid with PET images when preparing for a procedure. We recruited six Jefferson surgeons to evaluate the accuracy, usefulness, and applicability of 3D renderings of the organs surrounding a malignant pancreas prior to surgery. PET/CT and contrast-enhanced CT abdominal scans of a patient with a ductal pancreatic mass were segmented into 3D surface renderings, followed by co-registration. Version A used only the PET/CT image, while version B used the contrast-enhanced CT scans co-registered with the PET images. The six surgeons answered 15 questions covering a) the ease of use and accuracy of models, b) how these models, with/without PET, changed their understanding of the tumor, and c) what are the best applications of the 3D visualization, on a scale of 1 to 5. The six evaluations revealed a statistically significant improvement from version A (score 3.6±0.5) to version B (score 4.4±0.4). A paired-samples t-test yielded t(14) = −8.964, p<0.001. Across the surgeon cohort, contrast-enhanced CT fused with PET provided a more lifelike presentation than standard CT, increasing the usefulness of the presentation. The experienced surgeons consistently reported positive reactions to 3D surface renderings of fused PET and contrast-enhanced CT scans of a pancreatic cancer and surrounding organs. Thus, the 3D presentation could be a useful preparative tool for surgeons prior to making the first incision. This result supports proceeding to a larger surgeon cohort, viewing prospective 3D images from multiple types of cancer.
Improving text classification accuracy using topic modeling over an additional corpus

The World Wide Web has many document repositories that can act as valuable sources of additional data for various machine learning tasks. In this paper, we propose a method of improving text classification accuracy by using such an additional corpus that can easily be obtained from the web. This additional corpus can be unlabeled and independent of the given classification task. The method proposed here uses topic modeling to extract a set of topics from the additional corpus. Those extracted topics then act as additional features of the data of the given classification task. An evaluation on the RCV1 dataset shows significant improvement over a baseline method.
Simple models may help to study the complex relations between gut wall configuration and flow of luminal contents: speculation on the function of the colonic haustrations

Study of the motility of the gut and flow in the gut lumen is complex. We have used simple models of the colon to suggest that focal, segmental narrowing of the lumen of a large-bore tube produces an increase in distance traveled by solids and liquids compared to a tube of the same volume which has smooth cylindrical walls. This suggests that the colonic septae may promote efficient transit of solids and liquids even in an organ with large diameter.
Ultrafast generation of optical and acoustic phonons in nanocrystallites

Fil: Bragas, Andrea Veronica. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Instituto de Fisica de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisica de Buenos Aires; Argentina
Reverse iontophoresis — Parameters determining electroosmotic flow: I. pH and ionic strength

Abstract It has been previously demonstrated that electroosmosis (the convective movement of solvent that occurs through a charged ‘pore’ in response to the preferential passage of counter-ions when an electric field is applied) can be used in ‘reverse iontophoresis', where the imposition of an electric current across the skin is used to extract a substance of interest (e.g., glucose) from within or beneath the tissue to the surface of the body. The goal of the research reported here was to examine parameters which determine electroosmosis, such that the convective flow of solvent across the skin during iontophoresis may be maximized, and the sensitivity and precision of the procedure optimized. Using mannitol as an appropriate marker molecule, therefore, electroosmotic flow during reverse iontophoresis has been examined as a function of the pH and ionic strength of the electrolyte solutions contained within the electrode compartments located on the skin surface. The impact of using a limited set of different current waveforms was also studied. As expected from the permselectivity of the skin, extraction to the cathode was preferred over that to the anode at pH 7.4. Cathodal extraction was enhanced by increasing the pH of the surface electrolyte conversely, electroosmosis to the anode was improved by lowering the pH (due, presumably, to neutralization of the net negative charge on the ion-conducting pathways through the skin). Reducing the electrolyte ionic strength in the electrode chambers (relative to the physiological level present beneath the tissue) enhanced both cathodal (in particular) and anodal extraction; a minimum quantity of electrolyte, however, must be present in order to sustain the necessary electrochemistry of the iontophoretic system. Finally, neither periodic interruption of current flow, nor periodic alternation of electrode polarity (strategies which have been proposed to limit the acute irritation induced by constant current iontophoresis, i.e., allowing the skin an opportunity to ‘depolarize' ) adversely affected the overall efficiency of the extraction process.
Monitoring concrete reinforced with bonded surface plates by the acoustic emission method

Abstract Acoustic emission (AE) was studied in stressed structural beams composed of internally reinforced concrete with additional external reinforcement from thin bonded plates. A control beam without a bonded plate was compared to four beams having plates composed of carbon fibre composite, glass fibre composite, aramid fibre composite and steel. The dependence of acoustic emission on beam stiffness is described as well as a relation of the number of AE energy peaks to the number of visible cracks in the concrete. The Kaiser effect was observed in repeated loadings for all tested beams. Attenuation was measured to a distance of 2.75 m and was not found to be a limitation in acquiring useful data. The change in event rate and the energy above threshold were closely related to the number of cracks visible at the end of the test. The event rate consistently decreaed as the number of loading cycles increased. The results suggest that an examination of cumulative acoustic emission events and energy as a function of load can assist in analysing the cracking behaviour, loading history and stiffness of concrete beams externally reinforced with bonded surface plates.
Predictive Surface Generation and Characterization for Cylindrical Turning Processes

This paper presents a generalized simulation based approach for generation and characterization of turned surfaces based on process parameters and manufacturing errors. The presented model shows that with proper analytical modeling along with appropriate process monitoring system (force signals, vibration signals, spindle motion error signals etc.,) a comprehensive surface generation model can be developed. First, the tool nose geometry and cutting-force induced vibrations are superimposed to obtain the cutting tool path. Next, the information obtained from spindle motion errors is used to analytically formulate the position of each point on the machined surface. Regression models are fit to establish the relationship between form error / surface roughness and input parameters. The simulation-based approach presented here provides a quantitative bridge between process parameters/manufacturing errors and surface characterization metrics. Such a scheme would allow manufacturing engineers to pre-select processes, parameters, and capable machines to achieve design specification. This model will allow engineers to proactively control the influence of machining parameters on product quality through computer simulation, and, thus, “do things right the first time.”Copyright © 2005 by ASME
Managing Change: Quality in R&D at R. L. Mitchell Technical Center

ABSTRACTAfter several years of applying the Quality Improvement Process to R&D at the R.L. Mitchell Technical Center of Hoechst Celanese Corporation, it is useful to recap the experience to suggest where we have been and what sort of hurdles had to be overcome. Our experience may be useful to others who are involved in implementing quality programs in their own organizations. Their experience may be similar so far, and our experience may suggest what to expect. Our experience was superimposed upon substantial cultural changes in the corporation as it merged with American Hoechst to begin to develop a new corporate culture. We have found that under the umbrella of the corporate values were found not only quality, but also innovation and the management of meaningful change.
Organizational Metapaiterns Tacit Relationships in Organizational Culture

Recurring tacit patterns of relationships, called here metapatterns, represent an important, but largely neglected, focus for researchers interested in organizational culture. How metapatterns emerge and how they manifest themselves in organizational behavior is discussed at some length. Metapatterns, which comprise the tacit level of interpersonal and group interaction in organizations, are linked to other levels of analysis. The implications of metapatterns for the study of organizations are examined.
The optimal control problem for the Vidale-Wolfe advertising model revisited

The optimal control problem for the Vidale-Wolfe advertising model with unbounded controls is reformulated rigorously. It is shown that even though the optimal control is a measure of bounded variation, there exist physically realizable approximations to it. These smoother controls converge to the optimal control together with the induced trajectories and costs. Also, closed-form expressions are given for the optimal state trajectories and the induced costs.
Infants' Use of Shared Linguistic Information to Clarify Ambiguous Requests

Do infants use past linguistic information to interpret an ambiguous request for an object? When infants in this research were shown 2 objects, and asked for 1 with an indefinite request (e.g., “Can you get it for me?”), both 15- and 18-month-olds used the speaker's previous reference to an absent object to interpret the request. The 18-month-olds did so even when the request was made after a 2.5-min delay. When the request was made by a person who did not participate in the conversation, the infants did not use the previous verbal information. These results demonstrate infants' ability to use language as a source of information in ambiguous contexts and indicate an early appreciation of the shared nature of conversation.
Measuring plant canopy structure

The potential of three systems to quantify plant canopy structure, key input data to canopy reflectance models is examined. The results show an optical radar system is potentially capable of providing the most fundamental type of structural data, the area, and the direction of the normal of each small piece of foliage in each cube of space in the canopy. To decrease the size of the data set of canopy measurements needed to statistically characterize the structure of a plant canopy, it is proposed that the statistical methods of bootstrapping be employed and that plans of large caopies be measured one at a time.
Stable explicit schemes for equations of Schrödinger type.

A method for constructing explicit finite-difference schemes which can be used to solve Schroedinger-type partial-differential equations is presented. A forward Euler scheme that is conditionally stable is given by the procedure. The results presented are based on the analysis of the simplest Schroedinger type equation.