cssi/SciSciGPT-SciSciNet huggingface dataset:
Metasurfaces with engineered reflection and transmission: Optimal designs through coupled-mode analysis

Gradient metasurfaces have recently received significant attention for the unique opportunities they offer for advanced wave manipulation. Such metasurfaces are usually discrete implementations of surface impedance profiles, which are analytically derived to yield the desired operation. Several recent numerical and experimental studies have shown that gradient metasurfaces can work very well over large bandwidths, extending to frequencies where the definition of surface impedance is not straightforward. Here, we develop an alternative description of such metasurfaces based on coupled-mode theory and provide an explanation for this intriguing effect. Quite surprisingly, our theory shows that broadband anomalous reflection and transmission, does not necessarily require the use of spatial gradients, but they can be achieved through suitably designed periodic arrays of resonant particles. In addition to their theoretical importance, our results can be important for the design of efficient metasurfaces with specified frequency response.
The influence of native aortic valve calcium and transcatheter valve oversize on the need for pacemaker implantation after transcatheter aortic valve insertion.

Abstract Objective Native aortic valve calcium and transcatheter aortic valve oversize have been reported to predict pacemaker implantation after transcatheter aortic valve insertion. We reviewed our experience to better understand the association. Methods We retrospectively reviewed the records of 300 patients with no prior permanent pacemaker implantation who underwent transcatheter aortic valve insertion from November 2008 to February 2015. Valve oversize was calculated using area. The end point of the study was 30-day postoperative pacemaker implantation. Results Patient data included age of 81.1 ± 8.4 years, female sex in 135 patients (45%), atrial fibrillation in 74 patients (24.7%), Society of Thoracic Surgeons predicted risk of mortality of 7.6% (interquartile range [IQR], 5.3-10.6), aortic valve calcium score of 2568 (IQR, 1775-3526) Agatston units, and annulus area of 471 ± 82 mm 2 . Balloon-expandable valves were inserted in 244 patients (81.3%). Transcatheter aortic valve oversize was 12.8% (IQR, 3.9-23.3). Pacemaker implantation was performed in 59 patients (19.7%). Aortic valve calcium score (adjusted P = .275) and transcatheter valve oversize (adjusted P = .833) were not independent risk factors for pacemaker implantation when controlling for preoperative right bundle branch block (adjusted odds ratio, 3.49; 95% confidence interval, 1.61-8.55; P = .002), implantation of self-expanding valve (adjusted odds ratio, 4.09; 95% confidence interval, 1.53-10.96; P = .005), left bundle branch block (adjusted P = .331), previous percutaneous coronary intervention (adjusted P = .053), or valve surgery (adjusted P = .111), and PR interval (adjusted P = .350). Conclusions Right bundle branch block and implantation of a self-expanding prosthesis were predictive of pacemaker implantation, but not native aortic valve score or transcatheter valve oversize.
Self-Assessed Hearing Handicap in Older Adults With Poorer-Than-Predicted Speech Recognition in Noise

Purpose Even older adults with relatively mild hearing loss report hearing handicap, suggesting that hearing handicap is not completely explained by reduced speech audibility. Method We examined th...
Energy, water and nutrient impacts of California-grown vegetables compared to controlled environmental agriculture systems in Atlanta, GA.

Abstract The Central Valley in the State of California alone produces most of our nation’s fruits and vegetables and represents just 1% of the nation’s farmland. Since California’s recent drought was the worst in the last 1200 years, supply of these products may decrease and new sources are needed. To understand the efficacy of growing fruits and vegetables more locally, the energy, water and nutrient impacts of growing fruits and vegetables in local hydroponic and aquaponic controlled environment agriculture systems are compared to vegetables grown in California and shipped to Atlanta, GA. Hydroponically and aquaponically grown fruits and vegetables have areal productivities 29 and 10 times higher than CA-grown vegetables while hydroponically grown vegetables consume 30 times more energy than the CA-grown vegetables. There appears to be no difference in energy consumption between aquaponically- and CA-grown vegetables. On average, 66 and 8 times more water is used in CA-grown vegetables compared to the hydroponic and aquaponic growing techniques. Approximately double the nitrogen needed by plants is applied to CA-grown fruits and vegetables which suggests nitrogen is lost in runoff causing eutrophication downstream. There are 20, 348 and 10 times twenty times more rainfall, nutrients in domestic wastewater and vacant land needed to supply the water, nutrient and space requirements for vegetable production in Atlanta, GA.
Reflections on Six Decades of Research on Adolescent Behavior and Development.

These reflections, spanning six decades of involvement with developmental behavioral science, report on several salutary trends that have shaped that field of social inquiry, e.g., its increasingly trans-disciplinary character. They also take note of some of its enduring limitations, e.g., its failure to engage with theory. In addition, the reflections confront some current issues, such as the widespread stereotyping of adolescents as risk takers, and the growing recourse to reductionist explanation. On balance, however, developmental behavioral science can be seen in retrospect as having evolved in a decidedly positive direction. Clearly, it has yielded a firmer grasp on adolescent behavior and development.
Modern Measurement Technology: Miracle or Mirage?

(1978). Modern Measurement Technology: Miracle or Mirage? Proceedings of the Annual Conference of the Western College Reading Association: Vol. 11, Proceedings of the Eleventh Annual Conference of the WCRA. Learning Assistance: Charting Our Course, pp. 12-14.
Electronic Medical Record (EMR)

When many primary care physicians hear the phrase “electronic medical record,” what comes to mind is a jumble of text, numbers, and images flickering on a monitor in front of their eyes. The purpose of this chapter is to present an alternative approach to thinking about EMRs. The basics of elementary education have traditionally been summarized as the three R’s—reading, ’riting and ’rithmetic. The basics of elementary EMR education analogously are three Rs—reposit, report, and research. By concentrating on what we want computers to do for physicians, much of the hardware and software jargon that often plagues discussions about clinical computing can be dispensed with. This is a good thing because computer technology is rapidly evolving. Regrettably, many of the technical concepts referred to in the ensuing chapters may well be obsolete by the time this book finds its way to most of its eventual readership. The functionalities alluded to, in contrast, will endure.
The impact of kinetic parameters on cellulose hydrolysis rates

Abstract Mechanistic kinetic models are vital tools to elucidate rate-limiting interactions and processes hampering complete hydrolysis of cellulose by cellulases. Properly formulated, the models should ultimately simulate experimental cellulose hydrolysis time courses given that model parameters are known a priori. Here, we review reported values of critical parameters in cellulose hydrolysis (catalytic, adsorption/desorption, complexation/decomplexation rate constants and apparent processivity) and examine how estimation methods may impact the magnitudes and interpretation of the values. The sensitivity of the extents and rates of cellulose hydrolysis to the range of reported values were examined by conducting simulations with a general mechanistic model of TrCel7A hydrolysis of cellulose. When the simulation was conducted at enzyme-limiting conditions, initial bursts in cellulose hydrolysis rates were evident and highly sensitive to specific hydrolysis rates of productively bound enzymes and dissociation rates of non-productively bound enzymes. Under substrate limiting conditions, hydrolysis rates were significantly reduced and no initial burst was observed, with more pronounced sensitivity of hydrolysis rates to the range of kinetic values. Enzyme-substrate interaction rate constants reviewed here only capture short-time hydrolysis rate outcomes and future work to elucidate mechanisms of cellulose hydrolysis must also incorporate how substrate-limitations evolve over the course of hydrolysis.
High‐definition point‐of‐view intraoperative recording using a smartphone: A hands‐free approach

Objectives/hypothesis Intraoperative recording devices are being increasingly used to provide video for contemporary surgical training. The objective of this study was to evaluate the use of a smartphone as a low-cost alternative to obtain high-resolution video from the surgeon's perspective. Study design A study evaluating the feasibility of using a head-mounted smartphone with a telephoto lens for point-of-view surgical videography. Methods Video recordings of a rhinoplasty procedure were taken using a head-mounted smartphone and two handheld cameras, a Canon Powershot SD1400 IS and a Sony HandyCam HDR-CX160. Video clips were shown to 16 blinded otolaryngology residents (n = 10) and attending physicians (n = 6) for individual video evaluation using a Likert scale (1 being poor quality, 5 being excellent quality). In addition, the study participants were asked to select which video clip they preferred when presented to them side by side. Results The iPhone 7 was given the highest overall mean video quality rating of 3.9 ± 0.57 and was preferred over the two handheld cameras by nearly all surveyed surgeons. The Canon Powershot SD1400 IS was given a mean rating of 3.3 ± 1.0 and preferred over the SonyHandyCam HDR-CX160 by all surgeons. The Sony HandyCam HDR-CX160 was given a mean rating of 1.5 ± 0.13. Conclusions A head-mounted smartphone equipped with a telephoto lens provides a novel method to intraoperative surgical recording. The design is simple, low cost, and allows the surgeon to capture fine anatomical detail from the desirable point-of-view perspective. Level of evidence NA Laryngoscope, 129:578-581, 2019.
Turmoil Within a Civilization

In this chapter, we will see how the systemic yoyo model and the relevant results can be beautifully employed in the study of the peace and harmony between civilizations, and chaos experienced by civilizations, how economic prosperities travel, and how Westernization and modernization are related.
Antibiotics for Aspiration Pneumonia in Neurologically Impaired Children

Objective To compare hospital outcomes associated with commonly used antibiotic therapies for aspiration pneumonia in children with neurologic impairment (NI). Design/methods A retrospective study of children with NI hospitalized with aspiration pneumonia at 39 children's hospitals in the Pediatric Health Information System database. Exposure was empiric antibiotic therapy classified by antimicrobial activity. Outcomes included acute respiratory failure, intensive care unit (ICU) transfer, and hospital length of stay (LOS). Multivariable regression evaluated associations between exposure and outcomes and adjusted for confounders, including medical complexity and acute illness severity. Results In the adjusted analysis, children receiving Gram-negative coverage alone had two-fold greater odds of respiratory failure (odds ratio [OR] 2.15; 95% CI: 1.41-3.27), greater odds of ICU transfer (OR 1.80; 95% CI: 1.03-3.14), and longer LOS [adjusted rate ratio (RR) 1.28; 95% CI: 1.16-1.41] than those receiving anaerobic coverage alone. Children receiving anaerobic and Gram-negative coverage had higher odds of respiratory failure (OR 1.65; 95% CI: 1.19-2.28) than those receiving anaerobic coverage alone, but ICU transfer (OR 1.15; 95% CI: 0.73-1.80) and length of stay (RR 1.07; 95% CI: 0.98-1.16) did not statistically differ. For children receiving anaerobic, Gram-negative, and P. aeruginosa coverage, LOS was shorter (RR 0.83; 95% CI: 0.76-0.90) than those receiving anaerobic coverage alone; odds of respiratory failure and ICU transfer rates did not significantly differ. Conclusions Anaerobic therapy appears to be important in the treatment of aspiration pneumonia in children with NI. While Gram-negative coverage alone was associated with worse outcomes, its addition to anaerobic therapy may not yield improved outcomes.
A unified strategy to reverse-prenylated indole alkaloids: total syntheses of preparaherquamide, premalbrancheamide, and (+)-VM-55599

A full account of our studies toward reverse-prenylated indole alkaloids that contain a bicyclo[2.2.2]core is described. A divergent route is reported which has resulted in the synthesis of preparaherquamide, (+)-VM-55599, and premalbrancheamide. An intramolecular Dieckmann cyclization between an enolate and isocyanate was used to forge the bicyclo[2.2.2]diazaoctane core that is characteristic of these molecules. The pentacyclic indole scaffold was constructed through a one-pot Hofmann rearrangement followed by Fischer indole synthesis. The utilization of our previously reported indole peripheral functionalization strategy also led to natural products including malbrancheamides B, C, stephacidin A, notoamides F, I and R, aspergamide B, and waikialoid A. Ultimately, the divergent route that we devised provided access to a wide range of prenylated indole alkaloids that are differently substituted on the cyclic amine core.
Rocky Mountain Scholars Program: impact on female undergraduate engineering students: social and academic support, retention, and success

The Rocky Mountain Scholars Program (RMSP) was developed, in part, to improve student success and persistence in Engineering disciplines at Colorado State Universi-ty through a portfolio of engagement activities focused around undergraduate research experiences. Female RMSP participants exhibited substantially higher retention rates and grade point averages relative to other female engineering students at CSU. To better understand the impact of the RMSP, and its effectiveness among female engi-neering students, researchers focused on whether, and how, experiences and percep-tions differ between male and female students in engineering programs. That is, how do male and female students differ, if at all, in their subjective perception of life as an engineering major at CSU? A survey was developed measuring resilience, self-efficacy, motivation, social support, academic support, and perceived sexism. Data was obtained from 144 first-year engineering students at CSU. Results indicated that social support from extracurricular activities is particularly important among female students. This points to an increasing need for programs like the RMSP to create social networks among students and faculty, link students to the broader impacts of their work, and ultimately improve the undergraduate experience of under-represented groups in STEM programs.
Kv1.3 inhibition attenuates neuroinflammation through disruption of microglial calcium signaling

In the last 5 years inhibitors of the potassium channel KV1.3 have been shown to reduce neuroinflammation in rodent models of ischemic stroke, Alzheimer's disease, Parkinson's disease and traumatic brain injury. At the systemic level these beneficial actions are mediated by a reduction in microglia activation and a suppression of pro-inflammatory cytokine and nitric oxide production. However, the molecular mechanisms for the suppressive action of KV1.3 blockers on pro-inflammatory microglia functions was not known until our group recently demonstrated that KV1.3 channels not only regulate membrane potential, as would be expected of a voltage-gated potassium channel, but also play a crucial role in enabling microglia to resist depolarizations produced by the danger signal ATP thus regulating calcium influx through P2X4 receptors. We here review the role of KV1.3 in microglial signaling and show that, similarly to their role in T cells, KV1.3 channels also regulated store-operated calcium influx in microglia.
Thermomechanical properties and microstructures of yttrium hydride

Abstract Yttrium hydride is an optimal choice for a high-temperature moderator material in advanced thermal neutron spectrum reactors that require small core volumes. However, a complete database of the thermomechanical properties of yttrium hydride is not available yet, although it is much needed to understand and predict the moderator performance during service in reactors. In this paper, we report the properties of unirradiated bulk yttrium hydride as a function of hydrogen concentration—including density, crystal structure, specific heat capacity, thermal diffusivity, thermal conductivity, hardness, elastic/shear moduli, Poisson’s ratio, fracture strength, microstructure, and thermal stability—providing a baseline measurement for the subsequent neutron irradiation response study of yttrium hydride. The recommended empirical treatment of the data is suggested. In addition, other properties (i.e., hydrogen retention, thermal hydrogen migration, and irradiation response) that needs to be investigated are discussed.
LRRC15 is an inhibitory receptor blocking SARS-CoV-2 spike-mediated entry in trans

SARS-CoV-2 infection is mediated by the entry receptor ACE2. Although attachment factors and co-receptors facilitating entry are extensively studied, cellular entry factors inhibiting viral entry are largely unknown. Using a surface ome CRISPR activation screen, we identified human LRRC15 as an inhibitory receptor for SARS-CoV-2 entry. LRRC15 directly binds to the receptor-binding domain (RBD) of spike protein with a moderate affinity and inhibits spike-mediated entry. Analysis of human lung single cell RNA sequencing dataset reveals that expression of LRRC15 is primarily detected in fibroblasts and particularly enriched in pathological fibroblasts in COVID-19 patients. ACE2 and LRRC15 are not co-expressed in the same cell types in the lung. Strikingly, expression of LRRC15 in ACE2-negative cells blocks spike-mediated viral entry in ACE2+ cell in trans , suggesting a protective role of LRRC15 in a physiological context. Therefore, LRRC15 represents an inhibitory receptor for SARS-CoV-2 regulating viral entry in trans .
The age-distribution of cell cycle populations in plant root meristems. Complex tissues.

Abstract The durations of the mitotic cycle periods, the proportions of cells in each cycle period of the proliferative and nonproliferative populations, and the rates of cell progression from G1-S and from G2-M were used to characterize the cytokinetics in root meristems of four plant species. The observed age-distribution of cells in the cycle of each meristem was not comparable to either a theoretical exponential or uniform age-distribution. A more exact fit of the observed age-distributions with theoretical distributions was hindered by proliferative cells which halted temporarily in G1 and/or in G2 in relative proportions similar to the nonproliferative cells in the meristem. Moreover, the preponderant cycle period in which cells halted temporarily differed among the species observed: it was G1 in Helianthus and Triticum and G2 in Pisum and Vicia. The cell populations of these complex tissues can be subdivided kinetically into three types: (1) rapidly proliferating cells; (2) slowly proliferating cells that halt temporarily in G1 and/or in G2; and (3) nonproliferating cells that halt in G1 and/or in G2.
The Day-of-the-Week Effect in Stock Returns : Further Evidence from Eastern European Emerging Markets

Existing literature on the day-of-the-week stock return anomaly focuses mainly on the United States and other advanced economies with little or no attention to the emerging markets, including those of Eastern Europe. In an attempt to address this gap in the literature, this paper conducts an empirical investigation of the day-of-the-week stock return anomaly using major market stock indices in eleven Eastern European emerging markets (EEEM). The empirical results indicate negative Monday returns in six of the EEEMs and positive Monday returns in the remaining five. Two of the six negative Monday returns and only one of the five positive Monday returns are statistically significant. These findings provide no consistent evidence to support the presence of any significant daily patterns in the stock market returns of the EEEM.
The Complex Number System

We denote the set of all real numbers by ℝ. It is assumed that each reader is acquainted with the real number system and all its properties. In particular we assume a knowledge of the ordering of ℝ, the definitions and properties of the supremum and infimum (sup and inf), and the completeness of ℝ (every non-empty set in ℝ which is bounded above has a supremum). It is also assumed that every reader is familiar with sequential convergence in ℝ and with infinite series. Finally, no one should undertake a study of Complex Variables unless he has a thorough grounding in functions of one real variable. Although it has been traditional to study functions of several real variables before studying analytic function theory, this is not an essential prerequisite for this book. There will not be any occasion when the deep results of this area are needed.
Quantitative Analysis of Signaling Networks across Differentially Embedded Tumors Highlights Interpatient Heterogeneity in Human Glioblastoma

Glioblastoma multiforme (GBM) is the most aggressive malignant primary brain tumor, with a dismal mean survival even with the current standard of care. Although in vitro cell systems can provide mechanistic insight into the regulatory networks governing GBM cell proliferation and migration, clinical samples provide a more physiologically relevant view of oncogenic signaling networks. However, clinical samples are not widely available and may be embedded for histopathologic analysis. With the goal of accurately identifying activated signaling networks in GBM tumor samples, we investigated the impact of embedding in optimal cutting temperature (OCT) compound followed by flash freezing in LN2 vs immediate flash freezing (iFF) in LN2 on protein expression and phosphorylation-mediated signaling networks. Quantitative proteomic and phosphoproteomic analysis of 8 pairs of tumor specimens revealed minimal impact of the different sample processing strategies and highlighted the large interpatient heterogeneity present in these tumors. Correlation analyses of the differentially processed tumor sections identified activated signaling networks present in selected tumors and revealed the differential expression of transcription, translation, and degradation associated proteins. This study demonstrates the capability of quantitative mass spectrometry for identification of in vivo oncogenic signaling networks from human tumor specimens that were either OCT-embedded or immediately flash-frozen.
GATTing the Greens: Not Just Greening the GATT

environmental policymakers need not become entrenched. Both camps defend principles that foster long-term security and prosperity, deter irresponsible shift ing of costs to other nations or genera tions, and face a constant threat of ero sion from special interests. Much of the discussion to date has focused on possible legal refinements to the gatt to build environmental sensitivity into the inter national trading system. But creating a new parallel international regime designed to defend the environment as a necessary element of a prosperous global economy and to coordinate policies with the gatt would offer the prospect of a broader peace between the trade and environmental communities. Like gatt, it would provide a bulwark against domestic political pressures that under mine long-term thinking and serve as an honest broker for the economic future, allocating costs, benefits and responsibili ties in transnational disputes. In sum, instead of just "greening" the gatt, we should "gatt" the greens.
Simian immunodeficiency virus infection of monkeys as a model system for the study of AIDS pathogenesis, treatment, and prevention

As presented in this review, there are a number of different models of both natural and experimental infection of monkeys with primate lentiviruses. There are numerous different viruses and multiple different monkey species, making for a potentially large number of different combinations. The fact that each different combination of virus isolate and host macaque species may show different behavior underscores the need to understand the different models and their key features. On the one hand, this diversity of systems underscores the need to provide some standardization of the systems used for certain kinds of studies, such as vaccine evaluations, in order to facilitate the comparison of results obtained in different experiments, but in essentially the same experimental system. On the other hand, the rich diversity of different systems, with different features and behaviors, represents a tremendous resource, among other things allowing the investigator to select the system that best recapitulates particular aspects of human HIV infection for study in a relevant nonhuman primate model. Such studies have provided, and may be expected to continue to provide, important insights to guide HIV treatment and vaccine development in the future.
Elements of Supersymmetry

These notes are intended to provide an introduction to supersymmetry. The notes begin with supersymmetric quantum mechanics and the basic properties of spinor fields. The supersymmetry of simple theories of spin-zero and spin-one-half fields is discussed with emphasis upon the charges that generate the transformations of supersymmetry. Abelian and non-abelian supersymmetric gauge theories are characterized in their simpler and more general forms. Superfields are defined, and the concise notation they make possible is described. The minimal supersymmetric standard model is discussed with particular attention to the Higgs fields and the electro-weak superpotential.
Continuous monitoring of wide-area wireless networks: data collection and visualization

In this work, we present an infrastructure for monitoring and visualizing performance of a wide-area wireless network, We present a unique, vehicle-mounted platform and a testbed for wide-area wireless experimentation. The testbed nodes are mounted on metro transit city buses in Madison, WI, and are currently equipped with both cellular EV-DO* and WiFi interfaces. Our initial goal for this infrastructure is to continuously monitor characteristics and performance of large-scale wireless networks, e.g., city-wide mesh networks or cellular networks. In such networks, customers experience a very large range of geographic and mobility-related radio environments. A vehicle-mounted platform, with fairly deterministic mobility patterns, can provide an efficient, low-cost, and robust method to gather much needed performance data on parameters like RF coverage, available bandwidth, and impact of mobility. Our demonstration outlines the framework of such a distributed measurement system. We also showcase the potential benefits by presenting our initial measurements from this testbed through the use of intuitive visualization interface.
3α‐Hydroxysteroid Oxidoreductase in Rat Brain

We describe a simple procedure for the microassay of 3 alpha-hydroxysteroid oxidoreductase in homogenates of rat brain. This enzyme converts dihydrotestosterone to 3 alpha-androstandiol. We have mapped the distribution of the enzymatic activity in 14 regions of the rat brain. The highest activities were observed in homogenates of olfactory bulb (51/nmol/mg protein/h) and olfactory tubercle (29 nmol/mg protein/h). Substantially lower values were seen in the other brain regions, including thalamus, caudate nucleus, frontal cortex, hippocampus, hypothalamus, and preoptic area (6-20 nmol/mg protein/h).
Influence of conformation on the fluorescence of tryptophan-containing peptides

Conformational-energy calculations of the zwitterionic forms of Trp, Gly-Trp, Pro-Trp, Phe-Trp, Trp-Gly, Trp-Phe, Trp-Trp, and Trp-Gly-Gly were done using an empirical energy program for peptides (ECEPP). The resulting low-energy conformations were analyzed for the presence of hydrogen bonds, the distances between carbonyl groups and the indole ring, the distances between the N-terminal amino group and the indole ring, the dihedral angle between the planes containing carbonyl groups and the indole ring, and for dipeptides with two aromatic side chains, the dihedral angle and distance between the planes of the aromatic rings. This information was correlated with literature data from x-ray crystallographic studies, fluorescence lifetime studies, and quantum-yield experiments; proposed models of intramolecular quenching are discussed in light of the peptide conformations.
Temperature-Insensitive Miniaturized Fiber Inline Fabry-Perot Interferometer Fabricated by Femtosecond Laser

This article presents a miniaturized fiber inline Fabry-Perot interferometer (FPI), with an open micro-notch cavity fabricated by one-step femtosecond (fs) laser micromachining, for highly sensitive refractive index measurement. The device was tested for measurement of the refractive indices of various liquids including isopropanol, acetone and methanol at room temperature, as well as the temperature-dependent refractive index of deionized water from 3 to 90°C. The sensitivity for measurement of refractive index change of water was 1163 nm/RIU at the wavelength of 1550 nm. The temperature cross-sensitivity of the device was about 1.1×10−6 RIU/°C. The small size, all-fiber structure, small temperature dependence, linear response and high sensitivity, make the device attractive for chemical and biological sensing.Copyright © 2008 by ASME
The Determination of the Characteristics of Hydrostatic Bearings through the use of the Electric Analog Field Plotter

In many applications of hydrostatic lubrication to journal and thrust bearings, determination of flow, load carrying capacity and film thickness is at best an approximation. Anything but the simplest shape is difficult to analyze. The simplified form of Reynolds' equation which applies to hydrostatically lubricated bearings of constant film thickness is analogous to the electric field equation which describes the voltage distribution in a conducting sheet of constant thickness. This analogy suggests the use of the electric analog field plotter to determine the characteristics of hydrostatic bearings. In this paper the theoretical basis for this method is discussed. In addition, the solution of a journal bearing is presented along with equations for several other useful shapes. Experimental verification of the journal bearing solution is presented, which indicates that this method may be employed with considerable accuracy. Presented as an American Society of Lubrication Engineers paper at the Lubrication ...
In Vitro Evaluation of an Anticholinergic Agent in a Timed-Release Solid Dosage Formulation

Determinations of intact drug content and in vitro dissolution tests were carried out on a commercially available brand of the anticholinergic drug propantheline in 15-mg single-dose and 30-mg sustained-release tablets. These tests were made following a report of unsatisfactory therapeutic response in human subjects after ingestion of the 30-mg sustained-release dosage form. A chemical assay, specific for intact drug, showed that all tablets contained essentially the labeled amount of active drug species (± 4%). However, the slow dissolution of the first 15 mg of drug (a usual single dose) from the 30-mg dosage form, as observed in acidic solution (0.1 N HC1), was unexpected based on manufacturer claims. Older and fresher lots of the 30-mg formulation, both of which fell within a recently revised 2-year expiration period at the time of testing, released only 6.0 ± 1.4 mg of active ingredient during the 1st hr compared to 14.5 ± 0.7 mg from regular 15-mg tablets. Of the 30-mg tablets, the fresher lot released consistently more drug with time; the difference reached a statistically significant level of p 0.2) was evident between the older and fresher sustained-release lots at any time during 4-hr dissolution trials when the medium had been adjusted to pH 6.38 or above at 1 hr. In vitro dissolution test results correlated well with in vivo findings and showed that rapid dissolution of the initial 15 mg of propantheline from solid dosage forms in acidic gastric juices is critical to its therapeutic effectiveness. It was concluded that reformulation of the 30-mg sustained-release dosage form to promote more rapid release of the first 15 mg of drug or full reliance on single-dose tablets is necessary to ensure therapeutic efficacy.
IDENTIFICATION OF GANGLIOSIDES AS CONSTITUENTS OF EGG YOLK

Gangliosides were identified as constituents of the lipid fraction from egg yolk. Approximately 0.07 mμmole of ganglioside sialic acid was recovered per gram wet weight of yolk. Thin-layer chromatographic separation revealed the presence of at least eight separate ganglioside species in this fraction. Glucose, galactose, hexosamine and sialic acid, in the molar proportions of 1.00 to 1.25 to 1.95 to 1.19, were the major carbohydrates of yolk ganglioside fractions. Fourteen fatty acids were observed in the ganglioside fraction; 16:0 (26.6%) 18:0 (9.2%), 18:l (22.9%) and 22:0 (28.3%) were predominant.
Effects of Preloads of Water and Saline on Thermal Dehydration-Induced Thirst

Abstract BARNEY, C. C. Effects of preloads of water and saline on thermal dehydration-induced thirst. PHYSIOL BEHAV 61 (5) 763–769, 1997.—The relative contribution of cellular and extracellular water deficits to the genesis of thirst due to thermal dehydration was studied in male Sprague-Dawley rats following exposure to a 40°C environment for 4 h. Intragastric (IG) and intravenous (IV) preloads of water reduced the elevated plasma sodium and plasma osmolality of thermally dehydrated rats to control levels, but preloads of saline did not. IG and IV preloads of saline returned the hematocrit and plasma protein concentration of thermally dehydrated rats to control levels. Both the IG water preload and the IG saline preload reduced water intake, with the IG water preload having a greater effect. The IV water preload reduced water intake nearly to control levels, whereas the IV saline preload was without effect on water intake. These data indicate that the water intake of thermally dehydrated rats is primarily due to a cellular water deficit and that oral and gastric factors are also important in terminating water intake in thermally dehydrated rats.
Comparison of implantation of nonthoracotomy defibrillators in the operating room versus the electrophysiology laboratory

Abstract Implantable cardioverter-defibrillators (ICDs) with nonthoracotomy lead systems are widely available, and are implanted either in the electrophysiology laboratory or the operating room. The purpose of this study was to prospectively evaluate the safety and efficacy of nonthoracotomy ICD implantation in an electrophysiology laboratory versus an operating room. During a 7-month period, 62 consecutive ICDs with nonthoracotomy lead systems were implanted in patients in an electrophysiology laboratory. During the next 10 months, 110 consecutive ICDs were implanted in patients in a surgical operating room. All ICD implantations were performed under general anesthesia by electrophysiologists. There were no differences in age (58 ± 14 vs 62 ± 12 years , p = 0.06), gender distribution ( p = 0.3), frequency of structural heart disease (97% vs 97%, p = 0.9), ejection fraction (0.31 ± 0.15 vs 0.29 ± 0.13, p = 0.3), or presentation with cardiac arrest (65% vs 53%, p = 0.2) between patients undergoing ICD implantation in the electrophysiology laboratory and operating room, respectively. The rate of successful implantation and of complications for systems implanted in the electrophysiology laboratory (95% and 13%, respectively) and in the operating room (98% and 14%, respectively) were similar ( p = 0.4 and p = 0.8, respectively). Specifically, the rate of infection (0% vs 4%, p = 0.3) and hematoma formation (2% vs 4%, p = 0.8) were not statistically significantly different. Three patients who had undergone ICD implantation in an operating room died within 30 days. ICDs with nonthoracotomy lead systems can be implanted with a similarly high rate of success and acceptable complication rate in the electrophysiology laboratory and in the operating room.
Role of natural effector cells in the prevention of radiation-induced leukemogenesis

Four once-weekly exposures of 225 rads (R) of whole body X-irradiation causes a high incidence of lymphoma in C57BL/6 (C57) mice. The role of natural effector cells in radiation-induced leukemogenesis was investigated. Activity of natural killer (NK) and natural cytotoxic (NC) cells was depressed in irradiated mice over a prolonged period. Transplantation of bone marrow (BM) cells from normal C57 mice to irradiated mice restored their NK responses and prevented development of lymphoma. The effect of beige BM cell transfer to irradiated mice was not clear. Unlike short-term (4-hour) assay, results of long-term (20-hour) assay suggest partial restoration of NK and full restoration of NC activity in irradiated mice. Treatment of irradiated mice with polyinosinic: polycytidillic acid (poly I:C) increased NK activity and lymphoma resistance. Administration of small repeated doses of poly I:C to irradiated mice significantly prevented the development of lymphoma as well as significantly prolonging overall survival time in irradiated mice. These observations indicate that natural effector cells mediate resistance to radiation-induced leukemogenesis.
Liquid chromatography-tandem mass spectrometry assay for the simultaneous quantification of simvastatin, lovastatin, atorvastatin, and their major metabolites in human plasma

Millions of individuals are treated with a variety of statins that are metabolized to a variety of active metabolites. A single assay capable of simultaneously quantifying commonly used statins and their major metabolites has not been previously reported. Herein we describe the development and validation of a novel and robust liquid chromatography-tandem mass spectrometry assay for simultaneously quantifying simvastatin, lovastatin, atorvastatin, and their metabolites, simvastatin acid, lovastatin acid, para-hydroxy atorvastatin, and ortho-hydroxy atorvastatin in human plasma. Plasma samples were processed with a simple protein precipitation technique using acetonitrile, followed by chromatographic separation using an Agilent Zorbax Extend C18 column. A 12.0min linear gradient elution was used at a flow rate of 400μL/min with a mobile phase of water and methanol, both modified with 2mM ammonium formate and 0.2% formic acid. The analytes and internal standard, hesperetin, were detected using the selected reaction monitoring mode on a TSQ Quantum Discovery mass spectrometer with positive electrospray ionization. The assay exhibited a linear range of 1-1000nM for simvastatin acid and lovastatin acid, and a linear range of 0.1-100nM for the other analytes in human plasma. The accuracy and the within- and between-day precisions of the assay were within acceptable ranges, and the method was successfully utilized to quantify the statins and their metabolites in human plasma samples collected from an ongoing pharmacokinetic study.
Some results about the Chvátal conjecture

Let A1,A2,?,An be finite sets such that Ai?Aj for all i?j. Let F be an intersecting family consisting of sets contained in some Ai, i=1,2,?,n. Chvatal conjectured that among the largest intersecting families, there is always a star. In this paper, we obtain another proof of a result of Schonheim: If A1?A2???An??, then the conjecture is true. We also prove that if Ai?AjAk = ? for all i?j?k?i or if the independent system satisfies a hereditary tree structure, then the conjecture is also true.
Methotrexate hepatotoxicity in children with leukemia

Percutaneous liver biopsy was performed on seven children with acute lymphocytic leukemia who had received maintenance chemotherapy with high-dose intravenous methotrexate for 11/2 to 21/2 years. Portal fibrosis was found in four of the seven children and in an additional patient treated with oral methotrexate. Serial tests of liver function and 99m technetium-sulfur-colloid scans did not accurately identify children with hepatic fibrosis. Clinical evidence of liver disease was not seen.
Human factors in anesthesia: Risk assessment and clinical decision-making

Summary The perioperative setting is a complex environment in which critical events happen without warning and can quickly become life threatening. Clinical decision-making is the process by which a physician uses prior knowledge, reason, and the clinical scenario to formulate a diagnosis or treatment plan. Although this is usually an intuitive process, bias and cognitive errors may result in an incorrect course of action. Cognitive errors, which are "thinking mistakes", may be responsible for a large number of clinical errors, and cognitive forcing tools may help physicians to detect them and mitigate their effects.
Responses of squash to salinity, waterlogging, and subsequent drainage: II. Root and shoot growth

Abstract The responses of root and shoot growth to concurrent salinity and waterlogging, and subsequent drainage of summer squash (Cucurbita pepo) were studied in a greenhouse experiment. Plants were well watered or flooded with full‐strength Hoagland solution containing 100 mol/m3 sodium chloride (NaCl) or no NaCl for 14 d. Waterlogged plants were then transferred to drained conditions for 7 d of recovery, while salinized plants were continuously salinized until 21 d. Waterlogging led to greater reductions in root and shoot growth, and fruit yield than did salinity. Waterlogging stimulated production of adventitious roots; however, salinity suppressed this enhancement effect. A combination of waterlogging and salinity exacerbated the adverse effects of each factor alone on root and shoot growth. Seven days after termination of waterlogging, a full recovery occurred for number and length of adventitious roots, number of lateral roots, and root dry weight for waterlogged plants under non‐saline conditions,...
Release of immunoreactive-neuropeptide Y by rat platelets

Neuropeptide Y, a potent vasoconstrictor and cardiac depressant, is re-leased from sympathetic nerve endings. Its presence in megakaryocytes suggests this peptide might be stored in platelet granules and released during aggregation. Immunoreactive-neuropeptide Y was measured in platelet rich and platelet poor plasma, and was substantially greater in the former. Addition of collagen to platelets resulted in release of neuropeptide Y which paralleled, in a concentration-dependent manner, the degree of platelet aggregation. Adenosine diphosphate, at concentrations which induce only the first phase of aggregation and not the release reaction, caused only a minor release of neuropeptide Y. These results suggest that platelet release could be a major source of circulating neuropeptide Y and could contribute to hemodynamics of pathophysiological states involving platelet activation.
Issues of imaging science for future consideration

Abstract Acceleration of the emergence of imaging science as a new discipline will require the development of new organizational structures to foster research and educational programs that integrate components of the traditional disciplines, all of which stand to benefit. However, the greatest impact of imaging science will likely be from computer-based general educational programs that present both visual and verbal materials utilizing software that is not only interactive but also analytic, diagnostic, and adaptive in response to individual students. Ultimately, this powerful learning paradigm will have profound effects on all aspects of our culture. Imaging science will not have emerged fully until the conceptual, organizational, educational, cultural, and ethical issues it raises have been addressed.
Carbon monoxide oxidation on platinum-lead films

Abstract The influence of lead on CO oxidation depends on the lead-to-platinum surface atomic fraction. Below a value of about 0.20 the activity of the platinum-lead surface remains high. This “tolerance” of platinum to low lead levels could be due to lead strongly bound on platinum sites, which are not involved in CO oxidation. Above a lead surface atomic fraction of 0.2 rapid deactivation occurs. This reactivity behavior corresponds to a rapid decrease in the ability of PtPb films to chemisorb CO above a lead surface atomic fraction of about 0.2. It is suggested that this deactivation involves surface segregation of lead on catalytically active parts of the platinum metal surface.
Duplicate gene evolution, homoeologous recombination, and transcriptome characterization in allopolyploid cotton

Background: Modern allotetraploid cotton contains an “A” and “D” genome from an ancestral polyploidy event that occurred approximately 1–2 million years ago. Diploid A- and D-genome species can be compared to the A- and D-genomes found within these allotetraploids to make evolutionary inferences about polyploidy. In this paper we present a comprehensive EST assembly derived from diploid and model allotetraploid cottons and demonstrate several evolutionary inferences regarding genic evolution that can be drawn from these data. Results: We generated a set of cotton expressed sequence tags (ESTs), comprising approximately 4.4 million Sanger and next-generation (454) transcripts supplemented by approximately 152 million Illumina reads from diploid and allotetraploid cottons. From the EST alignments we inferred 259,192 genome-specific single nucleotide polymorphisms (SNPs). Molecular evolutionary analyses of protein-coding regions demonstrate that the rate of nucleotide substitution has increased among both allotetraploid genomes relative to the diploids, and that the ratio of nonsynonymous to synonymous substitutions has increased in one of the two polyploid lineages we sampled. We also use these SNPs to show that a surprisingly high percentage of duplicate genes (~7 %) show a signature of non-independent evolution in the allotetraploid nucleus, having experienced one or more episodes of nonreciprocal homoeologous recombination (NRHR). Conclusions: In this study we characterize the functional and mutational properties of the cotton transcriptome, produce a large genome-specific SNP database, and detect illegitimate genetic exchanges between duplicate genomes sharing a common allotetraploid nucleus. Our findings have important implications for our understanding of the consequences of polyploidy and duplicate gene evolution. We demonstrate that cotton genes have experienced an increased rate of molecular evolution following duplication by polyploidy, and that polyploidy has enabled considerable levels of nonreciprocal exchange between homoeologous genes.
Resistance of materials to abrasive penetration

Abstract The specific grinding energy is a material property defined as the energy required to remove a unit amount of material in an abrasive cutting process. It can be used for estimating rates of material removal or penetration and is therefore of interest in evaluating materials for security applications. Measurements of specific grinding energy are made for a variety of materials, including metals, plastics, ceramics and woods, subjected to an abrasive cut-off process; the importance of such data for the design of security barriers is discussed. The experimental apparatus designed and built for the purpose of making these measurements and the experimental technique are described.
What time travelers cannot do

Rejetant l'explication fataliste de l'impossibilite metaphysique pour un voyageur dans le temps de commettre son auto-infanticide, l'A. montre que le sens ordinaire du verbe pouvoir depend de notre evaluation des contrefactuels. L'histoire de notre passe delimite, non pas le monde possible des possibilites logiques, mais le monde clos des opportunites de nos actions