cssi/SciSciGPT-SciSciNet huggingface dataset:
'Baffling' design of a three mirror off-axis celestial telescope

Design approches to a space-based celestial telescope, called the Advanced Visible Telescope developed at the University of Arizona Optical Sciences Center, are reviewed with particular attention given to stray light reduction. The major design considerations intended to provide a stiff mounting structure for the optics and adjustments that simplify system alignment, and the introduction of baffles to provide stray-light rejection for off-axis sources are discussed. Two stray light rejection modeling methods are compared which were developed under SOAR (a program for rapid calculation of stray light on the IBM PC) and APART (a first order deterministic stray radiation analysis program). It is concluded that below the critical shading angle both programs show similar results but above critical shading angles there were discrepancies in results.
Dietary regulation of glycolytic enzymes. V. Lack of effect of intramuscularly administered sex steroid on male and female rat jejunum.

1. 1. The effects of intramuscular progesterone, 17β-estradiol and testosterone (100 μg/100 g body weight) upon the activities of five enzymes involved in carbohydrate metabolism [phosphofructokinase (ATP: D-Fru-6-P 6-phophotransferase, EC 2.7.1.11), pyruvate kinase (ATP: pyruvate phosphotransferase, EC 2.7.1.40), fructosediphosphatase (D-Fru-1,6-P2 1-phosphoghydrolase, EC 3.1.3.11), hexokinase (ATP: D-hexose 6-phosphotransferase, EC 2.7.1.1) and Fru-1,6-P2 aldolase (Fru-1,6-P2D-gluceraldehyde-3-P-lyse, EC4.1.2.13)] were studied in the jejunum of both male and female rats. 2. 2. Intramuscular administration of sex hormones (17β-estradiol, progesterone and testosterone) produced no demonstrable effect upon the activities of the jejunal carbohydrate-metabolizing enzymes in either male or female rats. However, intramuscular estradiol did significantly increase (P<0.01) the uterine activities of pyruvate kinase and phosphofructokinase as compared with normal control rats. 3. 3. The observations with intramuscular sex steroids are in marked contrast to the adaptive changes seen previously in jejunal enzyme activities following oral administration of the same dose of the same sex hormones1. Thus, it appears that the route of administration of the sex hormones plays a prominent role in the ability of these compounds to regulate jejunal enzyme activity
Animal procedure laboratory surveys: use of the animal laboratory to improve physician confidence and ability.

Animal laboratories have been used for many years to teach procedures. Our department has a weekly swine laboratory devoted to training residents, interns and students in resuscitative procedures. Physicians who participated in our swine procedure laboratory over the past three years were queried as to their prelaboratory and postlaboratory comfort levels with six different resuscitative procedures, and 57 (76%) physicians responded. Statistical analysis of the data showed significant improvement in comfort levels for all six procedures. Every responder felt the swine laboratory helped or will help them perform the procedures on humans. We also surveyed all U.S. emergency medicine residency program directors from established programs regarding the status of their animal procedure laboratories, and 67 of the 68 (98%) directors responded. Of these responders, 62% offer an animal procedure laboratory. Overall, 97% of the residency directors rated the laboratory successful, and 97% of the residents rated the laboratory successful. Therefore, we conclude that an ongoing emergency medicine animal procedure laboratory is a valuable tool for improving physician-in-training ability and confidence.
Inhibiting Aggregation of α-Synuclein with Human Single Chain Antibody Fragments†

The α-synuclein protein has been strongly correlated with Parkinson's disease (PD) and is a major component of the hallmark Lewy body aggregates associated with PD. Two different mutations in the α-synuclein gene as well as increased gene dosage of wild-type α-synuclein all associate with early onset cases of PD; and transgenic animal models overexpressing α-synuclein develop PD symptoms. α-Synuclein, a natively unfolded protein, can adopt a number of different folded conformations including a β-sheet form that facilitates formation of numerous aggregated morphologies, including long fibrils, spherical and linear protofibrils, and smaller aggregates or oligomers. The roles of the various morphologies of α-synuclein in the progression of PD are not known, and different species have been shown to be toxic. Here we show that single chain antibody fragments (scFv's) isolated from naive phage display antibody libraries can be used to control the aggregation of α-synuclein. We isolated an scFv with nanomolar af...
On Turbulent Flows with Fast Chemical Reactions. Part III: Two-Dimensional Mixing with Highly Dilute Reactants

Abstract Abstract-It is known that the analysis of the behavior of reactants and product in a turbulent shear flow according to the idealization of fast chemical reactions can be related to the probability density function of a passive scalar quantity. Several models for this function are assumed and their implications with respect to the distribution of mean concentrations in two-dimensional mixing layers are discussed. The most realistic model provides a methodology for systematically incorporating as much fluid mechanical information on the behavior of passive scalars as is available.
Planning and Using Skills Inventory Systems

The article reviews the book “Planning and Using Skills Inventory Systems,” by Richard A. Kaumeyer Jr.
Bimanual coordination during a goal-directed task in children with hemiplegic cerebral palsy

Most studies of impaired hand function in children with hemiplegic cerebral palsy (CP) have focused on either the involved or the non-involved extremity in isolation. Coordination of the involved and non-involved hand during bimanual tasks in these children is not well understood. The present study examined bimanual coordination using a drawer-opening task under speed and hand constraints in 10 children with hemiplegic CP (5 males and 5 females, mean age 13y 5mo, range 8y to 16y) and 10 age-matched right-handed developing typically children (6 males and 4 females, mean age 13y 1mo). Children were asked to reach forward and open a drawer with one hand and then activate a light switch inside the drawer with the contralateral hand. The role of the two hands (open drawer and activate switch) and speed (self-paced vs fast-as-possible) were varied. The children with hemiplegic CP were slower (p<0.001) and less coordinated in this task, with reduced movement overlap of the two hands (p<0.001) and sequential completion of the two movement objectives (p<0.001). Moreover, the hand used for each task subcomponent affected task performance for the children with hemiplegic CP (p<0.05). Interestingly, faster speed facilitated better bimanual coordination for the children with hemiplegic CP (p<0.001). Results highlight the importance of movement constraints on task performance and suggest that movement speed might facilitate better bimanual coordination.
Electron reflection, diffraction and imaging of bulk crystal surfaces in TEM and STEM

Reflection electron microscopy (REM) is a new technique for real space imaging of bulk crystal surfaces. The REM is performed in a transmission electron microscope (TEM) or a scanning TEM (STEM) using high-energy electrons at a grazing incidence angle. A comprehensive review has been given on basic techniques, fundamental physics, studies of surface reconstructions, and special applications of REM. Theoretical calculations have been described to illustrate the resonance scattering processes of electrons at the bulk crystal surfaces in the geometry of reflection high-energy electron diffraction (RHEED). Fundamental contrast mechanisms of REM have been illustrated to show the surface sensitivity of REM. Applications of REM for in-situ imaging of surface dynamic processes have been summarized for studies of metals, semiconductors, metal-on-semiconductors, semiconductor-on-semiconductors, and ceramics. Inelastic excitations of crystal surfaces in RHEED have been examined to demonstrate a technique, reflection electron energy-loss spectroscopy (REELS), for studying surface electronic structures and determining surface chemical compositions. Finally, novel techniques used in conjunction with REM, such a secondary electron imaging, scanning tunnelling microscopy (STM) and electron holography, have been described to show the future development of REM.
DESTABILIZING EFFECTS OF RATE FEEDBACK ON STRAIN ACTUATED BEAMS

Abstract The stabilizing and destabilizing effects of rate feedback control on all modes of a strain actuated beam are demonstrated here to support earlier theoretical findings by Balakrishnan [1] (1999 Journal of Computational and Applied Mathematics 18 ). The destabilizing effects being due to the actual implementation of the rate feedback controller which is unavoidably non-ideal. The main contribution here is the inclusion of the controller circuit model in the closed loop system equations to obtain correct stability estimates for all modes. Closed loop stability estimates computed from this circuitry enhanced model were corroborated by experiments. The strain actuated beam constructed for this work was made with a fiber glass lay-up and piezo ceramic wafers embedded throughout the length of the lay-up. A charge-to-voltage amplifier, a differentiator, a gain stage, and a power amplifier were also constructed. The most crucial of these components was the differentiator and its tank frequency. The first four modes and transmission zero frequencies, and the corresponding structural damping were obtained through open loop experiments. Mode estimates were within 5% of the computed values. Zero estimates were less accurate due to electric feedthrough, but modelling of this effect helped to improve zero frequency estimates. Closed loop experiments were run to demonstrate the destabilization of beam modes with frequencies higher than the differentiator's tank frequency.
Simultaneous Legionellosis and Invasive Aspergillosis in an Immunocompetent Patient Newly Treated With Corticosteroids

Invasive pulmonary aspergillosis (IPA), although unusual, has been recognized in the immunocompetent host. Several cases of IPA with rapidly progressive respiratory failure have been reported in patients receiving short-term corticosteroid therapy for chronic obstructive pulmonary disease. Atypical pneumonia caused by dual infection with Legionella pneumophila and Mycoplasma pneumoniae has also been reported. We report an unusual case of simultaneous L pneumophila pneumonia and IPA in an asthma patient with suspected allergic bronchopulmonary aspergillosis newly treated with corticosteroids.
The Desegregation Aims and Demographic Contexts of Magnet Schools: How Parents Choose and Why Siting Policies Matter

This paper is designed to specify a set of new opportunities for educators, school administrators, and scholars to realize the practical aims and strategic advantages envisioned in magnet schools. The paper is divided into three distinct sections. In Section I, we examine the extensive research literature on parents’ choice patterns and school preferences in magnet schools and other school-choice programs. In Section II, we compare the reasons parents choose particular schools with the criteria school districts use to select magnet school locations (and themes). This section highlights desegregation goals and district-level magnet school policies pegged to the following questions: What is the policy context for siting decisions in districts with magnet schools? Are siting policies strategically aligned with what is known from the research literature about parents’ school preferences? Do neighborhood characteristics play a part in magnet school siting policies and specific decision-making? In Section III, ...
Prospective Evaluation of Roux-en-Y Gastric Bypass as Primary Operation for Medically Complicated Obesity

Objective To determine prospectively the results of Roux-en-Y gastric bypass (RYGB) used as the primary weight-reducing operation in patients with medically complicated ("morbid") obesity. The RYGB procedure combines the advantages of a restrictive physiology (pouch of 10 mL) and a "dumping physiology" for high-energy liquids without requiring an externally reinforced (banded) stoma. Patients and Methods Between April 1987 and December 1998, a total of 191 consecutive patients with morbid obesity (median weight, 138 kg [range, 91–240 kg]; median body mass index, 49 kg/m 2 [range, 36–74 kg/m 2 ]), all of whom had directly weight-related morbidity, underwent RYGB and prospective follow-up. Results Hospital mortality was 0.5% (1/191), and hospital morbidity occurred in 10.5% (20/191). Good longterm weight loss was achieved, and patients adapted well to the required new eating habits. The mean ± SD weight loss at 1 year after operation (113 patients) was 52±1 kg or 68% ±2% of initial excess body weight. By 3 years postoperatively (74 patients), weight loss was still 66% ±2% of excess body weight. Overall, 53 (72%) of 74 patients had achieved and maintained a weight loss of 50% or more of their preoperative excess body weight 3 years after the operation. In addition, only 1 (1%) of 98 patients had persistent postoperative vomiting 1 or more times per week. Conclusion We believe that RYGB is a safe, effective procedure for most patients with morbid obesity and thus may be the current procedure of choice in patients requiring bariatric surgery for morbid obesity.
Signaling of Cytokines is Important in Regulation of GnRH Neurons

Cytokines encompass a broad class of peptides that mediate signals in a broad range of physiological situations including inflammation, infection, and obesity. The cytokine receptor-associated tyrosine kinase, Jak2, is one of the most important proteins mediating cytokine signaling pathway activation. Recently, our group has demonstrated that Jak2 signaling in the gonadotropin-releasing hormone (GnRH) neuron plays a critical role in fertility in males and females, implicating cytokine activation of the neuron in GnRH neuronal development and function. To date, the specific cytokine(s) essential for activating Jak2 during neuroendocrine development are not known. In this article, we review the evidence for the role of several class 1 cytokines in regulating GnRH neuronal development, GnRH secretion, and GnRH expression.
Evaluating E-Business Leadership and its Link to Firm Performance

Electronic business (e-business) has been popularly lauded as â€œnew economy.â€ As a result, firms are prompted to invest heavily in e-business related activities such as supplier/procurement and online exchanges. Whether the investments have actually paid off for the firms remain largely unknown. Using the data on the top 100 e-business leaders compiled by InternetWeek, the leaders are compared with their comparable counterparts in terms of profitability and cost in both the short-run and long-run. It is found that while the leaders have superior performance based on most of the profitability measurements, such superiority is not observed when cost measurements are used. Based on the findings, managerial implications are offered accordingly.
An Ecoregional Approach to the Economic Valuation of Land- and Water-Based Recreation in the United States

/ This paper describes a framework for estimating the economic value of outdoor recreation across different ecoregions. Ten ecoregions in the continental United States were defined based on similarly functioning ecosystem characters. The individual travel cost method was employed to estimate recreation demand functions for activities such as motor boating and waterskiing, developed and primitive camping, coldwater fishing, sightseeing and pleasure driving, and big game hunting for each ecoregion. While our ecoregional approach differs conceptually from previous work, our results appear consistent with the previous travel cost method valuation studies.KEY WORDS: Recreation; Ecoregion; Travel cost method; Truncated Poisson model
Published norms underestimate the health-related quality of life among persons with type 2 diabetes

Abstract Objective To assess health-related quality of life (HRQL) among adults with type 2 diabetes using the Short Form (SF)-36 and to obtain pooled estimates of HRQL for subpopulations defined by demographic characteristics, diabetes-related complications, and comorbidities. Study Design and Methods We conducted computerized searches of multiple electronic bibliographic databases, and studies in any language were selected in which HRQL was reported among adults with type 2 diabetes using the SF-36. Estimates were combined using a random-effects model. Results One hundred eighteen studies fulfilled the inclusion criteria. HRQL was lower in persons with type 2 diabetes, as measured by all the eight component scores of the SF-36 when compared with the existing U.S. population norms and with previously published type 2 diabetes norms. SF-36 component and summary scores were extremely heterogeneous, and subpopulation data were sparse; this precluded obtaining meaningful pooled scores for most populations of interest and made comparisons among subpopulations difficult. Conclusion Our data suggest that previously published norms may underestimate the effect of diabetes on HRQL, and diabetes populations are extremely heterogeneous, making broad population "norms" for HRQL in type 2 diabetes of limited use. Additional research with important subpopulations and individual-level data are needed to further explore the effect of diabetes on HRQL.
Prospective stereotaxy: A novel method of trajectory alignment using real‐time image guidance

Purpose: To describe prospective stereotaxy, a novel method of trajectory alignment that works in real-time. Materials and Methods: Prospective stereotaxy was used in minimally-invasive neurosurgical procedures in 74 patients since February 1999. This methodology differs from framed and frameless stereotaxy, both of which are based on retrospective data. Rather, prospective stereotaxy uses real-time MR images to align a surgical trajectory. Results: Phantom tests and clinical procedures in all patients were successfully performed using prospective stereotaxy. In all cases, surgical targets were accessed, and the diagnostic yield of neurobiopsy using prospective stereotaxy was 100%. Conclusion: Prospective stereotaxy is applicable to all cross-sectional imaging, and is particularly useful for MR- and CT-guided interventions. The method is simple, reproducible, and accurate in surgical targeting for neurobiopsy and electrode placement. It does not require cumbersome stereotactic frames or expensive optical detectors, and it offers immediate entry into the field of interventional MR with cylindrical MR scanners. J. Magn. Reson. Imaging 2001;13:452–457. © 2001 Wiley-Liss, Inc.
Family perceptions of medication administration at school: errors, risk factors, and consequences.

Medications are administered every day in schools across the country. Researchers and clinicians have studied school nurses’ and educators’ experiences with medication administration, but not the experiences of children or their parents. This study examined medication administration from the child and parent perspectives to (a) determine problems children experience with medicines at school, (b) clarify risk factors for medication errors, and (c) examine the perceived impact of medication errors on school performance and social relationships. Participants included children ages 8 to 18 years (n = 157) being treated at a large Midwestern Children’s Hospital in diabetes, asthma, and Attention Deficit Hyperactivity Disorder (ADHD) clinics. Findings suggest that forgetting a dose and running out of medication were the most common problems. Missing a dose was more frequent in students with ADHD than in students with diabetes or asthma. Medication nonadherence at school, which includes medication administration...
Relationship of transfusion and infection in a burn population

The relationship between the number of red blood cell transfusions and major infectious complications was evaluated in 594 thermal injury patients admitted between 1982 and 1986 who had burns over 10% or more of total body surface area and survived more than 10 days. The mean age of this group was 32.9 years, with a mean burn size of 36% of total body surface area; 83% were male. Of the 594 patients, 23.7% died and 38.7% had documented inhalation injury. The mean number of red blood cell transfusions received was 19.7, with a range of 0 to 201. Two hundred fourteen patients (36%) had major infectious complications, defined as pneumonia or invasive burn wound infection. A cross-tabulation of predicted mortality, number of transfusions, and infectious complications revealed a significant positive correlation between transfusion number and infectious complications in patients with predicted mortalities between 10 and 70%. Per cent total burn, patient age, presence of inhalation injury, and number of transfusions were identified by discriminant function analysis as significant variables (p less than 0.05) in discriminating between patients with and without infections (85% accuracy). Logistic regression analysis confirmed the above findings, showing a relationship between the number of transfusions received and infectious morbidity which was independent of age or burn size, but no significant relationship between number of transfusions and mortality.
Solitary Fibrous Tumor of the Pleura: A Cytogenetic Study

A solitary fibrous tumor of the pleura was studied. Its karyotype was 46,XY,t(6;17) (p11.2;q23),ins(9;12)(q22;q15q24.1),inv(16)(p13.1q24). The rearrangement of 12q13-15 was also described in a subset of hemangiopericytomas of soft tissue and meninges. Because both types of tumors are morphologically and immunophenotypically quite similar, and because some of them share rearrangement of 12q13-15, the possibility of their histogenetical relatedness should be considered.
Effects of implicit solvent and relaxed amino acid side chains on the MP2 and DFT calculations of ligand–protein structure and electronic interaction energies of dopaminergic ligands in the SULT1A3 enzyme active site

Abstract The electronic interaction energies between eight dopaminergic ligands and resveratrol and the SULT1A3 active site have been calculated using MP2 and M062X with the 6-311+G ∗ basis set. The SULT1A3 active site was isolated from the crystal structure with dopamine bound (PBD ID 2A3R). Structures for the nine ligands bound in the active site were obtained by three different optimization approaches with M062X/6-31G: by optimization in vacuo with rigid amino acid residue side chains ( i.e. using the side chain structures from the crystal structure; the ligand and all protons were optimized), with implicit solvation by water with rigid amino acid residue side chains, and with implicit solvation by water and relaxed amino acid residue side chains ( i.e. the ligand and all amino acid residue side chains were optimized). The calculations show that the use of implicit solvent and a relaxed active site offer considerable improvement in ligand interaction energies (more strongly binding), and that the solvated-relaxed model shows less variability in ligand interaction than the other two models. Finally, 6-carboxydopamine was shown to be the most strongly binding of the nine ligands, with an interaction energy over 100 kcal/mol stronger than its nearest neighbor. Four of the eight non-dopamine ligands studied interact with SULT1A3 more strongly than the endogenous ligand, dopamine, in the solvated-relaxed model.
On convexity of hypersurfaces in the hyperbolic space

In the Hyperbolic space $${\mathbb{H}^n}$$ (n ≥ 3) there are uncountably many topological types of convex hypersurfaces. When is a locally convex hypersurface in $${\mathbb{H}^n}$$ globally convex, that is, when does it bound a convex set? We prove that any locally convex proper embedding of an (n − 1)-dimensional connected manifold is the boundary of a convex set whenever the complement of (n − 1)-flats of the resulting hypersurface is connected.
Density-functional study of the pressure-induced phase transitions in Ti at zero Kelvin

The pressure-induced stable and metastable phase transitions of Ti at 0 K were studied by first-principles density-functional calculations. With the pressure from the equation of state fitting or extracted directly from first-principles calculations, we predicted that the 0 K phase transition sequence of Ti is $\ensuremath{\alpha}\ensuremath{\rightarrow}\ensuremath{\omega}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\rightarrow}\ensuremath{\beta}$, which is different from the theoretic predictions in the literature. We also found that the $\ensuremath{\delta}$ phase is not stable under hydrostatic compression. The obtained stable $(\ensuremath{\alpha}\ensuremath{\rightarrow}\ensuremath{\omega}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\rightarrow}\ensuremath{\beta})$ and metastable $(\ensuremath{\alpha}\ensuremath{\rightarrow}\ensuremath{\beta})$ phase transition pressures are in a good agreement with the experimental results. We found that the equation of state based on different fitting schemes can introduce significant errors in predicting the transition sequence of Ti. Our calculations also show that only under $\ensuremath{-}8.0\text{ }\text{GPa}$, the $\ensuremath{\beta}$ phase exhibits magnetism. However, it is energetically not stable with respect to the $\ensuremath{\alpha}$ and $\ensuremath{\omega}$ phases at low pressures.
Seasonal variation of tropical precipitation chemistry: La Selva, Costa Rica

Abstract The chemistry of wet precipitation was measured from February 1992 to February 1995 at La Selva Biological Station, Costa Rica. Sea salt aerosols were the primary contributors to Na + , Cl − , and Mg 2+ ; however, K + , Ca 2+ , and SO 4 2− were derived primarily from non-sea-salt sources. Seasonal patterns, with concentrations inversely proportional to rainfall, were found for marine salts and aerosols (Na + , Cl − , and Mg 2+ ) and inorganic nitrogenous compounds (NO 3 − and NH 4 + ). DON accounted for a significant fraction (30%) of total dissolved nitrogen deposition. Terrigenous dust from local agricultural or natural aeolian processes appeared to be the primary influence on concentrations of non-sea-salt cations. High concentrations of non-sea-salt sulfate (SO 4 ∗ ) were correlated with both non-sea-salt chloride (Cl * ) and high H + concentrations as well as a shift in wind direction from the northeast to the southwest, which may indicate a strong volcanic influence on precipitation chemistry during a few weeks of the year. Annual fluctuations in distribution and amount of rainfall contributed to differences in precipitation chemistry over the course of the study.
Lamb shift of an atom in a dielectric medium

Adapting an approach used by Feynman for the Lamb shift of an isolated atom, we obtain a nonperturbative expression for the Lamb shift of an atom in a dielectric medium, previously calculated perturbatively [P. W. Milonni, J. Mod. Opt. {bold 42}, 1191 (1995)]. The separation of the Lamb and Casimir components of the field energy is greatly simplified, and previous nonperturbative results for the Lamb shift [M. Schaden, L. Spruch, and F. Zhou, Phys. Rev. A {bold 57}, 1108 (1998)], based on the generalized argument theorem, are obtained much more easily and directly. {copyright} {ital 1999} {ital The American Physical Society}
TH-C-18A-11: Investigating the Minimum Scan Parameters Required to Generate Free-Breathing Fast-Helical CT Scans Without Motion-Artifacts

Purpose: A recently proposed 4D-CT protocol uses deformable registration of free-breathing fast-helical CT scans to generate a breathing motion model. In order to allow accurate registration, free-breathing images are required to be free of doubling-artifacts, which arise when tissue motion is greater than scan speed. This work identifies the minimum scanner parameters required to successfully generate free-breathing fast-helical scans without doubling-artifacts. Methods: 10 patients were imaged under free breathing conditions 25 times in alternating directions with a 64-slice CT scanner using a low dose fast helical protocol. A high temporal resolution (0.1s) 4D-CT was generated using a patient specific motion model and patient breathing waveforms, and used as the input for a scanner simulation. Forward projections were calculated using helical cone-beam geometry (800 projections per rotation) and a GPU accelerated reconstruction algorithm was implemented. Various CT scanner detector widths and rotation times were simulated, and verified using a motion phantom. Doubling-artifacts were quantified in patient images using structural similarity maps to determine the similarity between axial slices. Results: Increasing amounts of doubling-artifacts were observed with increasing rotation times > 0.2s for 16×1mm slice scan geometry. No significant increase in doubling artifacts was observed for 64×1mm slice scan geometry up tomore » 1.0s rotation time although blurring artifacts were observed >0.6s. Using a 16×1mm slice scan geometry, a rotation time of less than 0.3s (53mm/s scan speed) would be required to produce images of similar quality to a 64×1mm slice scan geometry. Conclusion: The current generation of 16 slice CT scanners, which are present in most Radiation Oncology departments, are not capable of generating free-breathing sorting-artifact-free images in the majority of patients. The next generation of CT scanners should be capable of at least 53mm/s scan speed in order to use a fast-helical 4D-CT protocol to generate a motion-artifact free 4D-CT. NIH R01CA096679.« less
A large spectrometer calibration chamber for SURF-II

Abstract A large spectrometer calibration chamber is under construction and scheduled for installation in early autumn this year. This system will be able to accomodate large spectrometer systems to be flown on the Space Shuttle Missions. The chamber is set up so that both translational and angular motions can be achieved to calibrate the optical system over its entire area. The control and calibration of the system will be under computer control.
Invited talk: Nano-electro-mechanical memory technology for future compact and ultra-low-power integrated systems

As demand for mobile and compact computing devices increases in the digital information age, the need for low-power, low-cost nonvolatile memory (NVM) increases. To overcome the challenges of high programming voltages and/or currents, slow programming speed, and small sensing margin for conventional NVM technology, a simple electro-mechanical diode cell design recently has been proposed and demonstrated [1]. This presentation will review the cell structure and operation, and discuss the scalability and reliability of this technology. A nanoscale (sub-100nm) electro-mechanical (NEM) NVM technology is projected to offer significant advantages in speed (sub-ns programming time) and power consumption (< 1 fJ program/erase energy) over other established and emerging NVM technologies, and hence shows promise for future ultra-low-power memory applications.
Synthesis and in vitro characterization of fluorinated U-50488 analogs for PET studies of kappa opioid receptors.

Abstract The κ type-specific opioid, U-50488 7 , was selected as a parent compound for the synthesis of an 18 F-labeled analog suitable for imaging κ opioid receptors with positron emission tomography (PET). The N -normethyl U-50488 analog 5 was synthesized as a precursor for fluoroalkylation, but it was found to be too unreactive for this technique. Instead, the desired N -fluoroalkyl analogs 10 , 11 were made by alkylation of trans -diaminocyclohexane precursor 4 with subsequent acylation. The in vitro binding affinity ( K i ) of these fluorinated ligands for the κ opioid receptor is reduced two orders of magnitude relative to U-50488. The decrease in binding affinity caused by the fluoroalkyl substitution renders these new analogs inappropriate for PET studies.
The source of midlatitude metallic ions at F-region altitudes

The results of a survey of metallic ions detected by the Bennett Ion Mass Spectrometer flown on the Atmospheric Explorer satellites are presented and discussed. The nighttime distribution of these ions observed in the F-region at middle latitudes can be accounted for by the presence of fast upward Pederson ion drifts that are produced by intense poleward-directed electric fields with magnitudes typical of those defining subauroral drift events. Such fields, which arise in the vicinity of the main electron density trough at night, result in the rapid movement of long-lived meteoric ions upwards out of their source region into the F-region. Neutral wind drag by the equatorially-directed nightside neutral wind component can lift the ions higher along the field lines until the downward drag of major ion diffusion forces them to layer under F-max.
Perception of moving, sounding objects by four-month-old infants

Infants and adults were presented with two moving objects accompanied by a single percussive sound. In different experiments, the sound occurred when one object moved through a particular spatial position, when it abruptly changed its direction of movement, or when it made contact with a rigid surface. Infants responded to the sound—object relationship whenever the sound occurred as the object changed direction, irrespective of its impacts with the surface. Adults, in contrast, responded to the sound—object relationship most clearly when sounds were synchronized with impacts. In infancy, perception of auditory—visual relationships thus depends in part on detection of discontinuities in the movement of a visible object.
Stereoselectivity of raney nickel catalyst in hydrogenolysis of a steroidal α,β-unsaturated epoxide. Chemical synthesis of 3β-benzoyloxy-5α-cholest-8(14)-en-15α-ol

Abstract Hydrogenation of 3β-benzoyloxy-14α, 15α-epoxy-5α-cholest-7-ene in benzene over a Raney nickel catalyst gave 3β-benzoyloxy-5α-cholest-8(14)-en-15α-ol and 3β-benzoyloxy-5α-cholest-8(14)-ene in 39% and 46% yields, respectively. Hydrogenation of the same α,β-unsaturated epoxy steryl ester under the same conditions except with the inclusion of triethylamine (4%) gave 3β-benzoyloxy-5α-cholest-8(14)-en-15α-ol in 89% yield.
Learning Transfer Principles in a Comprehensive Integration Model

In this article, the authors propose a comprehensive integration model (CIM) based on learning transfer principles that promote integration by systematically and multidimensionally linking coursework with field education. This model improves the integration of classroom and field instruction by specifying how content in each course and in the field is shared, by coordinating the learning process in both settings, and by defining the contributions of faculty, students, field instructors, and field liaisons.
On the equivalence of the operator and kernel methods for joint distributions of arbitrary variables

Generalizing the concept of time-frequency representations, Cohen (see Englewood Cliffs, NJ: Prentice-Hall, 1995) has proposed a method, based on operator correspondence rules, for generating joint distributions of arbitrary variables. As an alternative to considering all such rules, which is a practical impossibility in general, Cohen has proposed the kernel method in which different distributions are generated from a fixed rule via an arbitrary kernel. We derive a simple but rather stringent necessary condition, on the underlying operators, for the kernel method (with the kernel functionally independent of the variables) to generate all bilinear distributions. Of the specific pairs of variables that have been studied, essentially only time and frequency satisfy the condition; in particular, the important variables of time and scale do not. The results warrant further study for a systematic characterization of bilinear distributions in Cohen's method.
Human Perception-Driven, Similarity-Based Access to Image Databases

Similarity-based access to image databases assumes one or more similarity models. Although this assumption affects the retrieval precision of a system considerably, it is rarely described explicitly. Furthermore, because the similarity model is typically hard-coded into the system, it is very difficult if not impossible to use such a system for applications that do not fit the same similarity model. In this work, we develop a framework for designing similaritybased image access systems that are driven by human perception, and hence can be tailored for multiple, diverse applications. The driving components of the approach are Principal Components-based feature selection, perception modeling via psychophysical experiments and Genetic Algorithm-driven distance function optimization. While our framework is general and flexible, we demonstrate the application in a particular image access scenario: Shapebased retrieval of skin lesion images. The experimental results show that, by incorporating human perception of similarity into the system, retrieval performance may be significantly improved.
Equine Herpesvirus 1 Utilizes a Novel Herpesvirus Entry Receptor

The well-described herpesvirus entry receptors HveA (TNFRSF14), HveB (nectin 2), and HveC (nectin 1) have been shown to mediate the entry of alphaherpesviruses. Our findings showed that the alphaherpesvirus equine herpesvirus 1 (EHV-1) efficiently entered and replicated in CHO-K1 cells that lack the entry receptors HveA, HveB, and HveC, demonstrating that EHV-1 utilizes a unique entry receptor. As with other alphaherpesviruses, efficient EHV-1 entry was dependent on glycoprotein D and cell surface glycosaminoglycans.
Polarized electroproduction of charm

Abstract We discuss the NLO corrections to polarized electroproduction of charmed quarks.
Time-dependent convective instabilities in a closed vertical cylinder heated from below

The convective behaviour of xenon gas in a vertical thermally conducting cylinder (height/radius = 6) heated from below was investigated. Convectively induced temperature fluctuations in the gas were analysed with digital signal-processing techniques over a range of Rayleigh number 0 ≤ Ra [lsim ] 2300. Quiescent, steady-state, periodic and weakly turbulent convective regimes were characterized. Bistability of steady states (mode switching) was observed in the range 400 [lsim ] Ra [lsim ] 700. At Ra = 1550 a strictly periodic flow developed. With increasing Ra two additional incommensurate frequencies appeared, leading to ‘turbulence’ at Ra ≈ 2000. This turbulence, characterized by a broadband power spectrum, intermittently showed periodic flow. A periodic window with a period-doubling sequence appeared between 2100 [lsim ] Ra [lsim ] 2200. The spectral features of this sequence can be followed into the broad band noise at higher Ra. Although these experiments were conducted quasistatically, a strong hysteresis was observed with decreasing Ra. Furthermore, it was demonstrated that the sequence of convective regimes can be fundamentally altered by minor perturbations (self-heating) from the flow sensors.
Paradoxical Arterial Embolism Involving Both Upper Extremities in a Patient With Pulmonary Embolism and a Patent Foramen Ovale

Paradoxical embolization is an uncommon but devastating complication of pulmonary embolism (PE). Awareness of this complication with prompt recognition and treatment could serve to preclude significant disability and death. Described is a case of PE associated with paradoxical embolism to the arteries of both upper extremities. While patent foramen ovale (PFO) is common, paradoxical embolism is infrequent but can involve almost any artery of the body. Discussed are the risk factors, clinical presentations, and diagnostic and treatment options for paradoxical embolism. Awareness of the potential for paradoxical embolization in patients with PE is essential to its prompt recognition and treatment.
Thyroidectomy using the harmonic scalpel: analysis of 105 consecutive cases.

Objective: The purpose of this report was to evaluate the technical benefits, if any, of thyroidectomy using the harmonic scalpel versus conventional thyroidectomy. Study Design: One hundred five consecutive patients underwent thyroidectomy over 1 year with use of the harmonic scalpel. They were compared with a group of 20 patients who underwent thyroidectomy 1 year earlier using conventional techniques. Results: The incision length for those undergoing thyroidectomy with the harmonic knife averaged 4.5 cm compared with 5.5 cm for the conventional thyroidectomy group. The operating time for a hemithyroidectomy averaged 50 minutes for the harmonic scalpel group versus 80 minutes for the conventional technique. The operating time for a total thyroidectomy averaged 80 minutes for the harmonic scalpel group versus 120 minutes for the conventional thyroidectomy group. Conclusion: The use of the harmonic scalpel in thyroid surgery offers several advantages over the conventional technique. The incision length is shorter and the operating time is reduced. Bleeding is negligible and complications are few. Significance: The harmonic scalpel, whose use was pioneered in laparoscopic surgery, offers the thyroid surgeon the ability to safely and expeditiously control the feeding vessels through a limited field. (Otolaryngol Head Neck Surg 2002;127:284-8.)
Unitarity of the CKM matrix

I present a brief overview of measurements and calculations that establish the unitarity of the Cabibbo-Kobayashi-Maskawa matrix. I also discuss two experimental programs related to checking the unitarity of the CKM matrix: one tests isospin-breakmg corrections using T = 2 decays; and the other is an experiment to measure the beta asymmetry from polarized Ultra-cold Neutrons (UCNs), which could yield an accurate determination of V ud with different systematic uncertainties than existing data.
“KEEPING THE HEART”: NATURAL AFFECTION IN JOSEPH BUTLER'S APPROACH TO VIRTUE

This essay considers eighteenth-century Anglican thinker Joseph Butler's view of the role of natural emotions in moral reasoning and action. Emotions such as compassion and resentment are shown to play a positive role in the moral life by motivating action and by directing agents toward certain good objects—for example, relief of misery and justice. For Butler, moral virtue is present when these natural affections are kept in proper proportion by the “superior” principles of the moral life—conscience, self-love, and benevolence—which involve the capacity for reasonable reflection. For contemporary thinkers, Butler's approach suggests that natural emotion should not be viewed as the enemy of moral reasoning; in fact, it challenges ethicists to pay attention to and account for the significant role of the emotions in the moral life.
Signal amplitude conditioned density function for monopulse measurements of fixed-amplitude targets

Since the measured amplitude of the sum-signal of a monopulse radar is known in the receiver, the probability density function (PDF) for the monopulse measurements can be conditioned on the measured amplitude. The conditional PDF and related statistical properties are developed for the in-phase and quadrature parts of the monopulse measurements of fixed-amplitude targets. Conditions under which the conditional PDF can be approximated as Gaussian are considered. A decoupling of the estimation of the target amplitude and the monopulse processing is proposed for estimating the direction-of-arrival (DOA) for moderate to low SNR targets. Estimators of the variances of the monopulse measurements and the DOA estimate are also given for use in decision and control algorithms such as target tracking with a Kalman filter.
Rejection sensitivity and male violence in romantic relationships

Rejection sensitivity is the disposition to anxiously expect, readily perceive, and intensely react to rejection by significant others. A model of the role of this disposition in male violence toward romantic partners is proposed. Specifically, it is proposed that rejection sensitivity is a vulnerability factor for two distinct maladaptive styles of coping with intimate relationships. Rejection-sensitive men may attempt to prevent anticipated rejection by reducing their investment in intimate relationships. Alternatively, they may become highly invested in intimate relationships in search of an unconditionally supportive partner. Their low threshold for perceiving and overreacting to rejection, however, heightens their risk of responding aggressively to their partners’negative or ambiguous behavior. Cross-sectional data from 217 male college students supported predictions derived from the model. Among college men who reported relatively high investment in romantic relationships, anxious expectations of rejection predicted dating violence. Among men who reported relatively low investment in romantic relationships, anxious expectations of rejection predicted reduced involvement in discretionary close relationships with friends and romantic partners and, more generally, increased distress in and avoidance of social situations.
Convective-diffusive mass transfer inside complex micro-molds during electrodeposition

During fabrication, local variations in convective-diffusive mass transfer and current distribution can give rise to undesirable variations in material composition for electrodeposited microelectromechanical systems (MEMS). Local transport characteristics are normally difficult to analyze in complex microstructures, especially the convective-diffusive conditions present during device fabrication. To tackle this problem, we have developed an experimental method called "Process Archaeology." The general approach involves the electrodeposition of NiFe alloys from an electrolyte formulated to give a local composition that is very sensitive to the local mass transfer rate. Spatially-resolved measurements of the alloy composition and growth rate are accomplished by combining scanning electron microscopy and energy dispersive x-ray spectroscopy. Using a simple inverse problem formulation, these experimentally measured quantities are related to the local convective-diffusive mass transfer coefficient (k) and the local Sherwood number present during fabrication. Here the Sherwood number is defined as Sh=kH/D, where H is the thickness of the lithographic mask and D is the diffusivity of a key transport-controlled species. Electrodeposited microgears are used as a test bed for demonstrating "Process Archaeology." Sherwood number images show the wide ranges of mass transfer rates and the complex mixing features present during microgear fabrication, especially in the region downstream of the microgear's central hub.
“Why Does Rain Fall?”: Children Prefer to Learn From an Informant Who Uses Noncircular Explanations

These two studies explored 3- and 5-year-olds' evaluation of noncircular and circular explanations, and their use of such explanations to determine informant credibility. Although 5-year-olds demonstrated a selective preference for noncircular over circular explanations (Experiment 1: Long Explanations; Experiment 2: Short Explanations), 3-year-olds only demonstrated a preference for the noncircular when the explanations were shortened (Experiment 2). Children's evaluation of the explanations extended to their inferences about the informants' future credibility. Both age groups demonstrated a selective preference for learning novel explanations from an informant who had previously provided noncircular explanations-although only 5-year-olds also preferred to learn novel labels from her. The implications and scope of children's ability to monitor the quality of an informant's explanation are discussed.