cssi/SciSciGPT-SciSciNet huggingface dataset:
Comparing textbook outcomes among patients undergoing surgery for cancer at U. S. News & World Report ranked hospitals

Background The objective of the current study was to define and compare rates of textbook outcomes (TO) among patients undergoing colorectal, lung, esophagus, liver, and pancreatic surgery for cancer at U.S. News & World Report (USNWR) ranked hospitals. Methods Medicare Inpatient Standard Analytic Files 2013-2015 were utilized to examine the relationship of TO and USNWR hospital ratings following surgery for colorectal, lung, esophageal, pancreatic, and liver cancer. TO was defined as no postoperative surgical complications, no prolonged length of hospital stay, no readmission within 90 days after discharge, and no postoperative mortality within 90 days after surgery. Results Among the 35,352 Medicare patients included in the cohort, 16,820 (47.6%) underwent surgery at honor roll hospitals, whereas 18 532 (52.4%) underwent surgery at non-honor roll hospitals. The overall proportion of patients who achieved TO was 50.1%. In examining the clinical outcomes of patients who underwent surgery, there was no difference in the odds of achieving TO at honor roll vs non-honor roll hospitals (colorectal: odds ratio [OR], 0.87; 95% confidence interval [CI], 0.69-1.10; lung: OR, 1.07; 95% CI, 0.87-1.32; esophagus: OR, 1.44; 95% CI, 0.72-2.89; liver: OR, 1.27; 95% CI, 0.87-1.84; pancreas: OR, 1.04; 95% CI, 0.67-1.62). Conclusion and relevance Patients undergoing surgery for lung, esophageal, liver, pancreatic, and colorectal cancer had comparable rates of TO at honor roll vs non-honor roll hospitals. No linear association was observed between hospital position in the rank and postoperative outcomes such as TO indicating that patients should not overly focus on the exact position within USNWR ranked hospitals. These data highlight to patients and physicians that up to one-half of patients undergoing surgery for cancer should anticipate at least one adverse outcome.
Innovation Born in Isolation: Rapid Transformation of an In-Person Medical Student Radiology Elective to a Remote Learning Experience During the COVID-19 Pandemic.

Rationale and Objectives With social distancing measures in place both nationally and globally, the current COVID-19 pandemic has forced the cancellation of in-person classes at universities and medical schools across the country. This has presented unique challenges for educators in all fields as they have embarked, many for the first time, on the journey into remote education in order to provide distance learning opportunities for students. Materials and Methods In this article we will review our approach to rapidly converting an in-person diagnostic radiology elective to an entirely remote learning experience for medical students at our institution, including modification of course structure, software tools and materials utilized, and strategies for learner engagement and collaboration. Results Development of an online elective led to a 10-fold increase in student enrollment compared to the traditional course offering, providing a unique opportunity to reach a broad number of students, many of whom were in the early clinical stages of their medical school career. Lastly, we will review faculty feedback after participating in the remote course as well as lessons learned from the transition to distance learning and its implications for future work Conclusion The current state of technology makes radiology particularly well-suited for distance learning, and with the proper tools and approaches, effective remote radiology instruction can be achieved.
Investigation of the reaction mechanism of the hydrodeoxygenation of propionic acid over a Rh(1 1 1) surface: A first principles study

Abstract Microkinetic models based on first principles calculations have been used to study the vapor and liquid phase hydrodeoxygenation of propionic acid on a Rh(1 1 1) surface. Calculations suggest that both decarboxylation and decarbonylation do not occur at an appreciable rate under all reaction environments. Propanol and propionaldehyde are the main products on this surface and they are produced at similar rates in both vapor and liquid phase environments. While a condensed phase can shift the reaction rate, the dominant pathways and selectivity towards the various products are hardly affected. At 473 K, the turnover frequency is increased by about a factor of 1.5 in liquid water relative to the gas phase. In liquid 1,4-dioxane, the turnover frequency is also slightly increased relative to the gas phase. Given the uncertainty in Rh cavity radius in the liquid phase calculations, computations with different cavity radii have been performed. With larger Rh cavity radius, the promotional effect of the solvents on the turnover frequency becomes more significant, while practically no changes are observed for a smaller cavity radius.
Towards ultralow detection limits of aromatic toxicants in water using pluronic nanoemulsions and single-entity electrochemistry.

Abstract We demonstrate a new electroanalytical technique using nanoemulsions (NEs) as a nanoextractor combined with single entity electrochemistry (SEE) to separate, preconcentrate analytes from bulk media, and even detect them in situ, enabling ultratrace level analysis. This approach is based on our hypothesis that the custom-designed NEs would enable to effectively scavenge compounds from bulk media. Herein, we use Pluronic F-127 functionalized NEs to extract, preconcentrate target analytes e.g., ferrocene derivatives as a model aromatic toxicant dissolved in the water, and employ SEE to in situ detect and quantitatively estimate analytes extracted in individual NEs. Extraction was markedly efficient to reach ∼8 orders of magnitude of preconcentration factor under the true equilibrium, thereby enabling ultratrace level analysis with a detection limit of ∼0.2 ppb. The key step to attain high sensitivity in our measurements was to modulate the total amount of added NEs respect to the total volume of bulk solution, thereby controlling the extracted amount of analytes in each NE. Our approach is readily applicable to investigate other aromatic toxicants dissolved in the water, thus detecting hazardous carcinogen, 2-aminobiphenyl in the water up to ∼0.1 ppb level. Given the excellent detection performance as well as the broad applicability for ubiquitous aromatic contaminants, the combination of NEs with SEE offers great prospects as a sensor for environmental applications.
Resuscitation After Hemorrhagic Shock in the Microcirculation: Targeting Optimal Oxygen Delivery in the Design of Artificial Blood Substitutes

Microcirculatory preservation is essential for patient recovery from hemorrhagic shock. In hemorrhagic shock, microcirculatory flow and pressure are greatly reduced, creating an oxygen debt that may eventually become irreversible. During shock, tissues become hypoxic, cellular respiration turns to anaerobic metabolism, and the microcirculation rapidly begins to fail. This condition requires immediate fluid resuscitation to promote tissue reperfusion. The choice of fluid for resuscitation is whole blood; however, this may not be readily available and, on a larger scale, may be globally insufficient. Thus, extensive research on viable alternatives to blood has been undertaken in an effort to develop a clinically deployable blood substitute. This has not, as of yet, achieved fruition, in part due to an incomplete understanding of the complexities of the function of blood in the microcirculation. Hemodynamic resuscitation is acknowledged to be contingent on a number of factors other than volume expansion. The circulation of whole blood is carefully regulated to optimize oxygen delivery to the tissues via shear stress modulation through blood viscosity, inherent oxygen-carrying capacity, cell-free layer variation, and myogenic response, among other variables. Although plasma expanders can address a number of these issues, hemoglobin-based oxygen carriers (HBOCs) introduce a method of replenishing the intrinsic oxygen-carrying capacity of blood. There continue to be a number of issues related to HBOCs, but recent advances in the next-generation HBOCs show promise in the preservation of microcirculatory function and limiting toxicities. The development of HBOCs is now focused on viscosity and the degree of microvascular shear stress achieved in order to optimize vasoactive and oxygen delivery responses by leveraging the restoration and maintenance of physiological responses to blood flow in the microcirculation. Blood substitutes with higher viscous properties tend to improve oxygen delivery compared to those with lower viscosities. This review details current concepts in blood substitutes, particularly as they relate to trauma/hemorrhagic shock, with a specific focus on their complex interactions in the microcirculation.
Charpy impact energy absorption of 3D printed continuous Kevlar reinforced composites

Additive manufacturing (AM) has been used widely to produce three-dimensional (3D) parts from computer-aided design (CAD) software. Traditional Fused Deposition Modeling (FDM) 3D printed polymer pa...
Nature of trapping forces in optically induced electrothermal vortex based tweezers

Precise manipulation of micro and nanosized particles has enabled investigations into various applications ranging from mechanobiology of biomolecules and cells to self-assembly of two-dimensional colloids. This work is focussed on studying the nature of a noninvasive electrothermal vortex based micro-manipulation tool called rapid electrokinetic patterning (REP). Using the equipartition method, we show that a REP trap is Hookean in nature and has an ultralow trap stiffness on the order of femtonewtons/\ensuremath{\mu}m. The dynamic tunability of an optically induced REP trap makes it a versatile tool for various biophysical applications.
A Study Aimed at Understanding the Use of Nanomaterial-Treated Filters for the Uptake of Heavy Metals from Water Sources

We describe the synthesis and optical properties of ligand-modified gold nanoparticles in solution and grown on stainless-steel wool filters. Their efficiency with regard to heavy metal uptake from water found at or near DOE facilities was also tested. Two different sequestration technologies for heavy metals were developed based on the surface functionalization of gold nanoparticles with either citrate or L-cysteine. Citrate-capped gold nanoparticles in solution show a greater heavy metal loading capacity than L-cysteine-functionalized gold nanoparticles. It was also found that the citrate-capped gold nanoparticles have a greater sensitivity for copper (II) than zinc (II) ions. L-cysteine-capped gold nanoparticles are more sensitive toward gradual uptake of zinc (II) ions making them valuable for sensing and sequestration applications. L-cysteine-capped gold nanoparticle stainless-steel wool filters are also efficient at the uptake of heavy metal ions. The nanomaterial-treated stainless-steel wool filters are advantageous because they serve as inactive supports allowing efficient flow of the contaminated water and can be easily replaced after heavy metal uptake. They are also comparable to nanomaterials free in solution with regard to the effectiveness of remediation of contaminated water resources.
Spin-phonon interactions in Quantum Spin Liquid Candidate α-RuCl 3

We study spin-phonon interactions in quantum spin liquid candidate RuCl 3 under magnetic fields of up to 6T and mK temperatures with polarization-resolved Raman spectroscopy.
Clinical Neurologic Issues in Cerebrovascular Monitoring

Cerebral blood flow is normally matched to substrate demand; this process of autoregulation is disrupted in many disease states, and often results in secondary ischemic damage that impairs outcome beyond the effects of an initial insult. Cerebral perfusion pressure, the difference between mean arterial pressure and intracranial pressure, is the most commonly measured parameter employed in the management of patients with increased intracranial pressure. More recent techniques, including brain tissue oxygen measurement and microdialysis, increase our ability to detect evidence of cerebral ischemia. Management of patients with such ischemia, or in danger of developing it, has classically depended on raising mean arterial pressure or lowering intracranial pressure. Newer treatments add ways of improving oxygen delivery to ischemic tissue in the hope of minimizing secondary injury.
The φ meson

The φ meson was observed by Bertanza et al. (1962a) in the reactions $$\begin{array}{*{20}{c}} {{K^ - } + p \to \Lambda + {K^0} + {{\bar K}^0},} \\ { \to \Lambda + {K^ + } + {K^ - }.} \end{array}$$ .
Video Listening Tests: A Pilot Study

Listening has long been the neglected skill in second language acquisition research, teaching, and assessment. However, in recent years there has been an increased focus on L2 listening ability because of its perceived importance in language acquisition. The present study explored the listening process when the aural input was delivered through the use of video. Video texts were used because video allows listeners to perceive and process nonverbal information. A model of L2 listening ability was hypothesized and operationalized, and an assessment instrument was created. This video listening test was administered to 85 ESL students. The data from this test were then analyzed using reliability analyses and Exploratory Factor Analysis (EFA). The results seem to provide some evidence for the validation of a two-factor model of listening based on the ability to comprehend explicitly stated information, and the ability to comprehend implicit information in aural texts.
High Resolution Coronographic Imaging of AG Carinae

We present the first high resolution observations of the ring nebula around the galactic LBV AG Car obtained through broad band B, V, R, I filters with the STScI coronograph on the ESO 2.2 m. telescope. Highly anisotropic continuum emission in all these bands is clearly detected, in the shape of a bipolar structure elongated along the NE- SW direction extending from a few arcsecs from the star out to ≤ 15 arcsecs corresponding to a projected linear distance of ≤ 0.5 parsecs, with a surface brightness in the range 17.9–19.4 mag/arcsec2. Its essentially neutral color with respect to the star (Δ(V-I) = -0.07) suggests that the observed radiation is starlight scattered by dust grains of diameter > 1/μ.
Palladium-catalyzed carboxylation of allyl stannanes and carboxylative coupling of allyl stannanes and allyl halides

The reaction of allyl stannanes with CO 2 to form stannyl carboxylates (esters) is catalyzed by Pd(PR 3 ) 4 complexes. Thus, R 3 SnCH 2 CH=CH 2 [R=Me and Ph]are converted to R 3 SnO 2 CCH 2 CH=CH 2 and R 3 SnO 2 CCH=CHCH 3 under 33 atm of CO 2 (70°C, THF) in moderate to excellent yield in the presence of 8 mol% Pd(PPh 3 ) 4 ; polycarboxylation of diallyldibutyltin and tetraallyltin also is effected, producing the respective di- and tetracarboxylates, Bu 2 Sn(O 2 CCH 2 CH=CH 2 ) 2 and Sn(O 2 CCH 2 CH=CH 2 ) 4 , along with the corresponding isomeric crotyl derivatives. In the presence of allyl halides, allyl stannanes and CO 2 undergo carboxylative coupling to produce allyl esters. Under these conditions other Sn-C (Sn-alkyl, -aryl, -vinyl) and Si-C (Si-allyl, -alkyl, -aryl, -vinyl) bonds are inert to carboxylation and carboxylative coupling with allyl halides. A tentative mechanism is proposed to account for this catalytic carboxylation of a main group metal-carbon bond.
Localized surface phonon polariton resonators in GaN

GaN micro-disk resonator arrays were fabricated and measured within the Restrahalen band of GaN. Far-IR spectroscopy shows evidence for localized surface phonon polariton resonances, results which are confirmed by finite-element models of the fabricated structures.
Calcium homeostasis in Trypanosoma brucei. Identification of a pH-sensitive non-mitochondrial calcium pool.

Abstract The objective of this study was to characterize mechanisms which maintain intracellular calcium homeostasis in bloodstream forms of Trypanosoma brucei. The identification of homeostatic pathways is required to understand signal transduction in these organisms. The fluorescent probes Fura-2, 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein, and bisoxonal were used to measure intracellular calcium ([Ca2+]i), intracellular pH (pHi), and membrane potential, respectively. Homeostatic pathways maintained [Ca2+]i at 98 +/- 12 nM in the presence of 1.8 mM extracellular calcium despite a steady leak of calcium into the cell. The addition of 2.7 microM nigericin acidified the cytosol, depolarized the plasma membrane, and induced an approximate 3-fold increase in [Ca2+]i. The rise in [Ca2+]i could not be induced with valinomycin or gramicidin D under conditions where membrane depolarization occurred. By contrast, the proton ionophore, carbonyl cyanide p-trifluoromethoxyphenylhydrazone, elevated [Ca2+]i in a manner that was not additive with nigericin. Changes in pHi appeared to regulate [Ca2+]i since: 1) stepwise addition of K+ to nigericin-treated cells generated and incremental increase in pHi and concomitant decrease in [Ca]i; 2) addition of serum to nigericin-treated cells allowed simultaneous recovery of pHi and [Ca2+]i; and 3) addition of NH4Cl to untreated cells resulted in a biphasic change in pHi with corresponding biphasic change in [Ca2+]i. The rise in [Ca2+]i was derived from an intracellular pool which was not dependent on functional cytochrome oxidase, mitochondrial alternative oxidase, or the F0F1-ATPase. These data demonstrate that large quantities of calcium are reversibly stored in a non-mitochondrial pH-sensitive intracellular pool in T. brucei. We conclude that changes in pHi can serve to trigger calcium signals in these organisms.
Primary ground displacements and seismic energy near the gnome explosion

Abstract Near-source measurements of seismic waves from gnome have been compared with a theoretical seismic source model derived by Blake (1952). It is estimated that 75 percent of the seismic energy in the primary waves is contained in the first half cycle of the ground displacement as shown on the seismograms from instruments located between 0.3 and 10 km from the explosion. The geometrical attenuation of the radiation field of the displacement wave is probably closely approximated by spherical divergence at ranges near the explosion. There is some evidence that a long-period displacement field may exist near the explosion as predicted by the theoretical model. However, there are not sufficient empirical data from the gnome explosion to make a detailed comparison between theory and observation.
Commutative Schur Rings of Maximal Dimension

A commutative Schur ring over a finite group G has dimension at most s G = d 1 + … +d r , where the d i are the degrees of the irreducible characters of G. We find families of groups that have S-rings that realize this bound, including the groups SL(2, 2 n ), metacyclic groups, extraspecial groups, and groups all of whose character degrees are 1 or a fixed prime. We also give families of groups that do not realize this bound. We show that the class of groups that have S-rings that realize this bound is invariant under taking quotients. We also show how such S-rings determine a random walk on the group and how the generating function for such a random walk can be calculated using the group determinant.
Isolation from Pasteurella multocida of a Lipopolysaccharide Antigen with Immunizing and Toxic Properties

Abstract A heat-stable, particulate, lipopolysaccharide-protein antigenic complex has been isolated from a virulent, encapsulated strain of Pasteurella multocida by extraction with cold, formalinized saline, and centrifugation at 105,000 × g. The original bacterial culture had been obtained from a bison that died of hemorrhagic septicemia, an infectious disease of cattle and buffalo. Injection of fractional milligram amounts of the antigen into mice, rabbits, and calves produced toxic reactions which frequently resulted in death of the host. The surviving animals demonstrated a high degree of immunity to challenge with live, virulent organisms. Two injections with 15 μg of the antigen produced a high degree of immunity in mice without the development of any signs of toxicity. The gross chemical composition and toxicity of the antigen were similar to those reported for endotoxins obtained by the Boivin or Westphal procedure. Although strong serological cross-reactions were obtained in Ouchterlony plates between the 105,000 × g antigens from the bison strain and an avian strain with antisera to these strains, these antisera agglutinated only the bacterial cells of the homologous strain. The active immunity obtained in mice by the injection of the 105,000 × g antigens of each strain was specific and could be correlated with the agglutination tests.
The Performance, Risk, and Diversification of Sector Funds

Sector funds' self-imposed limits on diversification have both costs and benefits. Sector funds tend to perform as well as other equity funds, but their performance tends to be sensitive to the benchmark that is used. In addition, sector-fund managers do not exhibit any significant persistence in performance. Although sector funds tend to be moderately less diversified than other equity funds, they do not entail greater systematic risk. Sector funds exhibit larger total risk than the control sample, but they are not any riskier than small-cap and aggressive-growth funds. Factor analysis results provide evidence that variation in sector-fund returns can be attributed to two common underlying factors, and the primary factor appears to be the return on the market index.
Lying to Care for Patients: Hegelian Tragedy or MacIntyrean Triumph?

The article by Tavaglione and Hurst (2012) takes up the incredibly pertinent and pressing moral issue of “gaming the system,” wherein physicians lie in order to obtain medically indicated treatment...
Carbon uptake, growth and resource-use efficiency in one invasive and six native Hawaiian dry forest tree species

Photosynthetic gas exchange, nitrogen- and water-use efficiency, leaf water potential and seasonal patterns of leaf production were studied in seven, dominant dry-forest species from the island of Lana'i, Hawaii, including the rapidly colonizing, non-native Schinus terebinthifolius (Raddi). We evaluated whether unique physiological characteristics of the invasive species explain its capacity to rapidly invade dry forests throughout the Hawaiian Islands. Apparent anomalies in stable carbon isotope data (delta13C) relative to other results led us to study effects of environmental conditions and physiological performance during leaf expansion on delta13C. Species that expanded all their foliage at the beginning of the wet season had more negative leaf delta13C values during the dry season than species with continuous leaf expansion. Among species, S. terebinthifolius had a strong seasonal pattern of leaf production and the most negative delta13C (-29 per thousand). With respect to almost every trait measured, S. terebinthifolius fell at an end of the range of values for the native species. Rapid growth of S. terebinthifolius in this ecosystem may be partially explained by its high maximum CO2 assimilation rates (15 micromol m-2 s-1), low leaf mass per area, high photosynthetic nitrogen-use efficiency per unit leaf mass or area and large decrease in stomatal conductance during the dry season. Relative to the native species, the invasive species exhibited striking phenotypic plasticity, including high rates of stem growth and water and CO2 uptake during the wet season, and maintenance of leaves and high leaf water potentials, as a result of reduced water loss, during the dry season, enabling it to utilize available resources effectively.
Reflective acousto-optic modulation with surface acoustic waves

A reflective optical modulator based on acousto-optic modulation of light by a mirror corrugated with surface acoustic waves is presented. Modulation of optical amplitude, frequency, and phase is demonstrated at visible (633- and 488-nm) and deep UV (244-nm) wavelengths. The reflective modulator has eight channels and achieves a maximum first-order diffraction efficiency of 6.0%.
Vitamin C Stimulates Sphingolipid Production and Markers of Barrier Formation in Submerged Human Keratinocyte Cultures

Human keratinocytes differentiate in vitro in response to a variety of stimuli, but neither the levels nor the spectrum of ceramides approach those seen in vivo . Ceramide production increases when human keratinocytes are grown at an air–liquid interface, and alterations in ceramide content occur when vitamin C is added to air-exposed, organotypic culture systems (Ponec et al . J Invest Dermatol 109:348, 1997). Here, we assessed whether vitamin C stimulates sphingolipid production in human keratinocytes independent of differentiation and air exposure. When submerged, human keratinocytes were grown in 1.2 mM calcium and serum-containing medium with vitamin C (50 µg per ml) for 9 d, total lipid content remained unchanged, but both glucosylceramide and ceramide content increased. Moreover, selected ceramide and glucosylceramide species: i.e., nonhydroxy ceramide 2 and both α- and ω-hydroxylated sphingolipids, increased preferentially [ceramide 4 (6-hydroxy-acylceramide), ceramide 5 (α-hydroxyceramide), ceramide 6 (4-hydroxy-α-hydroxyceramide), and ceramide 7 (6-hydroxy-α-hydroxyceramide); and acylglucosylceramide, glucosylceramide-B, and glucosylceramide-D], whereas ceramide 1, ceramide 3, glucosylceramide-C, and sphingomyelin remained unchanged. Synthesis of the corresponding ceramide and glucosylceramide fractions was enhanced by vitamin C, attributable, in part, to increased ceramide synthase activity (over 2-fold, p=0.01); both serine palmitoyltransferase and glucosylceramide synthase activities remained unaltered. Finally, increased vitamin C-stimulated sphingolipid production correlated with the presence of lamellar bodies with mature internal contents, an increase in covalently bound ω-hydroxyceramide, and the appearance of prominent, corneocyte-bound lipid envelopes, whereas cornified envelope formation was unchanged. Thus, in submerged human keratinocytes, vitamin C induces both increased sphingolipid production and enhancement of permeability barrier structural markers.
Effects of water vapor on activated carbon load equalization of gas phase toluene

Experimental testing and numerical simulations were conducted to assess the effects of elevated water vapor concentrations on the ability of granular activated carbon (GAC) to achieve load equalization of dynamically varying gas-phase toluene concentrations. Columns packed with Calgon BPL 4 x 6 mesh GAC were subjected to intermittent (8 h/day) toluene loading in air streams containing up to 90% relative humidity. Influent toluene concentrations ranged from 100 to 1000 ppm(v), and GAC column empty bed residence times ranged from 1.5 to 10 s. In comparison to load equalization performance achieved with dry air, high relative humidity improved load attenuation at high influent toluene concentration (e.g., 1000 ppm(v)) but decreased the degree of load attenuation at low influent toluene concentration (e.g., 100 ppm(v)). Model simulations conducted using a pore and surface diffusion model were in good general agreement with experimental observations. Collectively, results demonstrate that GAC columns can be of practical benefit as passively-operated load equalization devices even in the case of high relative humidity. Such systems may prove useful as a pre-treatment process for biofilters and other air pollution control devices that would otherwise be subjected to wide variation in contaminant loading.
Vowels as Islands of Reliability.

Vowel nuclei of syllables appear to provide a relatively stable (although not stationary) frame of reference for judging consonant events. We offer evidence that reliable consonant identification demands prior or simultaneous evaluation of this “vocalic frame.” Listeners were presented a list of /bVs/, /dVs/, and /gVs/ syllables and were instructed to press a response key immediately upon recognizing a particular initial consonant target. Three groups of subjects monitored for /b/, /d/, and /g/, respectively. The test syllables contained 10 English vowels varying substantially in intrinsic duration. Response times to the initial consonants correlated positively with the duration of the following vowels, even when the effect of consonant-vowel formant transition duration was partialed out. The results suggest that consonant recognition is vowel dependent and, specifically, that a certain amount or proportion of the vowel formant trajectory must be evaluated before consonants can be reliably identified.
Ryanodine receptor adaptation and Ca2+(-)induced Ca2+ release-dependent Ca2+ oscillations

A simplified mechanism that mimics "adaptation" of the ryanodine receptor (RyR) has been developed and its significance for Ca2+(-)induced Ca2+ release and Ca2+ oscillations investigated. For parameters that reproduce experimental data for the RyR from cardiac cells, adaptation of the RyR in combination with sarco/endoplasmic reticulum Ca2+ ATPase Ca2+ pumps in the internal stores can give rise to either low [Cai2+] steady states or Ca2+ oscillations coexisting with unphysiologically high [Cai2+] steady states. In this closed-cell-type model rapid, adaptation-dependent Ca2+ oscillations occur only in limited ranges of parameters. In the presence of Ca2+ influx and efflux from outside the cell (open-cell model) Ca2+ oscillations occur for a wide range of physiological parameter values and have a period that is determined by the rate of Ca2+ refilling of the stores. Although the rate of adaptation of the RyR has a role in determining the shape and the period of the Ca2+ spike, it is not essential for their existence. This is in marked contrast with what is observed for the inositol 1,4,5-trisphosphate receptor for which the biphasic activation and inhibition of its activity by Ca2+ are sufficient to produce oscillations. Results for this model are compared with those based on Ca2+(-)induced Ca2+ release alone in the bullfrog sympathetic neuron. This kinetic model should be suitable for analyzing phenomena associated with "Ca2+ sparks," including their merger into Ca2+ waves in cardiac myocytes.
Energy dependence of H-exchange versus CC bond formation in the complex [CH3OH CH2CH+2]: unimolecular and bimolecular studies

The reactions of the ion—neutral complex [CH3OH CH2CH+2] have been examined by unimolecular and bimolecular approaches. We conclude that the distonic ion CH3OH+ CH2CH2 (1) isomerizes to CH3CH2CH2OH+ (5) via the internal ion—molecule reaction [CH3OH CH2CH+2] → [+HOCH2CH2CH3] followed by CC bond formation. Metastable H and H2O losses follow this isomerization. About 60 kJ mol−1 higher (attained by collision-induced dissociation and reaction of CH2CH+2 with CH3OH) CH2OH+ and CH3OH+2 are formed. Hydrogen exchange between oxygen and ethene occurs at this energy, but CC bond formation does not. Hydrogen atoms exchange by interconversion of ion-neutral complexes rather than by isomerizations involving formation of distonic ions. At 33 kJ mol−1 higher still (reaction of CD3OD+ with CH2CH2), H-transfer without exchange occurs. The reactions of [CH3OH CH2CH+2] are thus strongly energy dependent.
Antimicrobial Residue Detection in Chicken Yolk Samples Following Administration to Egg-Producing Chickens and Effects of Residue Detection on Competitive Exclusion Culture (PREEMPT) Establishment

Competitive exclusion (CE) cultures may offer alternatives to antimicrobial agents for disease prophylaxis in poultry. To avoid potential transfer of antibiotic resistance, safe and effective CE cultures must, by necessity, be highly sensitive to antimicrobial residues. The following studies evaluated the effect of maternal administration of selected antibiotics on the establishment of a licensed CE culture, PREEMPT. Selected antibiotics were administered to actively laying hens for a period of 7 days (experiment 1) or 9 days (experiment 2) in drinking water [sulfadimethoxine (0.05%), enrofloxacin (0.005%), and tylosin tartrate (0.05%)] or feed (sulfadimethoxine with ormetoprim, 250 ppm). In experiment 1, fertile eggs were collected daily and subjected to bioassay for detectable antimicrobial residues in yolk. Antimicrobial residues were not detected during the 7 days of treatment or the subsequent 3 days following cessation of treatment in the control, sulfadimethoxine, sulfadimethoxine with ormetoprim, or tylosin treatment groups. However, detectable residues were observed in eggs derived from enrofloxacin-treated hens on days 6 and 7 during antibiotic administration and also on days 2 and 3 post-antibiotic administration. In experiment 2, antimicrobial residues were also only detected in yolks from hens treated with enrofloxacin. Residue detection occurred on days 2-6 of antibiotic administration, on day 9 of antibiotic administration, on days 1-3 post-antibiotic administration, and also on day 7 post-antibiotic administration. A subset of eggs from each experimental group, corresponding to days 2-6 of antibiotic administration, days 4-6 post-antibiotic administration, and days 14-16 post-antibiotic administration, were pooled for incubation, and chicks hatched from these pools of fertile eggs were treated with PREEMPT at hatch. When 48-h cecal propionate concentrations were used as an index of culture establishment, reduced (P < 0.05) efficacy was observed only in chicks derived from enrofloxacin-treated hens at either collection period. Although several antibiotics do not appear to produce detectable egg residues or interfere with CE culture establishment, these data suggest that chicks derived from enrofloxacin-treated hens may not be candidates for safe and effective CE culture treatment.
BRIGHTNESS FLUCTUATIONS IN THE K-LINE WINGS

A power-spectrum and cross-spectrum analysis has been made of measurements of temporal fluctuations of intensity observed in the K-line wing (2.07 A from line center) and of simultaneous measurements of temporal fluctuations of Doppler displacement of the cores of λ3931.122 Fe i and λ3933 Ca ii (K3). The measurements were made in a quiet region near the center of the Sun's disk. We find that the average power spectra of the intensity fluctuations have two significant peaks of about equal strength: one at 0.0033 Hz (300-s period); and one at about 0.001 Hz (1000-s period). The average rms value of these intensity fluctuations is 0.0435±0.0082. Maximum brightness comes before maximum violet displacement of the Fe i line. The mean of the best determined phases is 137° and of all the data 108°. At those places on the Sun where the 300-s oscillations can be identified in the k3 core, the Doppler displacement of the Fe i line leads that of the K3 core by a mean phase angle of 27°.
Reliability Testing of 4H-SiC Bipolar Junction Transistors in Continuous Switching Applications

Continued improvement in silicon carbide (SiC) material processing has allowed development of efficient high temperature devices which are uniquely suited to power electronics circuit designs. The 4H-SiC structure has several intrinsic characteristics that facilitate optimal speed and power handling during high temperature device operation. These characteristics include wide bandgap (3.2 eV), high dielectric breakdown (3.5 MV/cm), and high thermal conductivity (4.9 W/cm-K)[1,2]. By combining these properties, SiC bipolar junction transistors (BJTs) can achieve fast, low impedance switching at high voltages (1.2 kV). New generation devices are being developed with increased current handling capability, as well as improved forward voltage characteristics. The device considered here, along with its on-state DC characteristic, is shown in figure 1. The BJTs are approximately 5mm by 5mm, and are nominally rated for a maximum Ice of 50A. Measurements on the Tektronix 371B curve-tracer indicate current gains over 60 at 25 oC and roughly 40 at 150 oC. These results were obtained at collector currents up to 20A. The base current for BJTs is typically 300 to 800 mA, depending on device temperature and the maximum device current required. In order to meet current handling requirements of up to 80A, as required for power conversion in modern military systems such as the hybrid-electric vehicle (HEV), it is necessary to configure these devices in parallel with minimal external cooling. The resulting switching circuits must therefore be validated for operation at high temperatures (package temperatures of 90 oC, and junction temperatures to 150 oC). Validation includes characterization of the devices in clamped inductive circuits with devices configured both alone and in parallel over time. Figure 4 shows measurement waveforms obtained during continuous clamped inductive switching. The primary focus of this work is to establish the overall performance and reliability of these newer generation SiC BJTs in power conversion circuits. Failure analysis and critical performance issues, such as current sharing, energy loss, and total reverse recovery charge are addressed. The initial results of the experiments indicate that these SiC switches have the potential to perform reliably in high temperature power conversion.
A Practical Approach to Sequential Estimation of Systematic Error on Near-Surface Mesoscale Grids

Abstract Statistical analysis arguments are used to construct an estimation algorithm for systematic error of near-surface temperatures on a mesoscale grid. The systematic error is defined as the observed running-mean error, and an averaging length of 7 days is shown to be acceptable. Those errors are spread over a numerical weather prediction model grid via the statistical analysis equation. Two covariance models are examined: 1) a stationary, isotropic function tuned with the observed running-mean errors and 2) dynamic estimates derived from a recent history of running-mean forecasts. Prediction of error is possible with a diurnal persistence model, where the error at one time of day can be estimated from data with lags of 24-h multiples. The approach is tested on 6 months of 6-h forecasts with the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5) over New Mexico. Results show that for a quantity such as 2-m temperature, the systematic component of error can be effectively predic...
Tests of high current hollow cathodes for ion engines

The development of high power, high thrust ion engines requires the development of long life hollow cathodes capable of producing emission currents of hundreds of amperes. This paper describes results obtained through the extended testing of two 12.7 mm diameter hollow cathodes at high emission currents. The first cathode, operated on xenon for a total of 170 hours at an emission current of 100 A, sustained very little damage except for an increase in the cathode orifice diameter, from 0.953 to 1.71 mm. The second cathode was operated on xenon at 150 A emission current continuously for 24 hours, and for over 1000 hours at 100 A on argon with essentially no change in the cathode operating characteristics. Operation of this cathode was terminated due to severe erosion of several discharge chamber components located downstream of the cathode. The erosion of these components occurred despite operation at discharge voltages less than 24 volts, and poses a serious challenge to the sucessful implementation of multi-hundred ampere cathodes and high thrust ion engines.
What's in a Name? Child Life and the Play Lady Legacy

Child life specialists can now earn a nationally recognized credential as a "Certified Child Life Specialist" from the Child Life Certifying Commission Yet, uncertainties linger about the nature of the child life specialist's identity roles, and status among health care professionals This article highlights the historical contexts within which a series of significant changes occurred in the profession's name How Emma Plank and Thest Bergmann, two pioneering authors in the field, influenced and were influenced by the play lady legacy is shown, and recommendations are made to find ways to honor the profession's past, while addressing the challenges of the 1990s.
The effect of ethnic group on sexual activities related to contraception and stds

There is a paucity of empirical data available on how ethnicity affects various sexual behaviors on college campuses. A questionnaire was mailed to a random sample of college students, and 1,173 students completed the questions requesting information about their sexual, contraceptive and STD‐related behavior. Minority students—Asians, Blacks, and Latinos—were oversampled in order to test numerous effects of ethnic group on selected sexual, contraceptive, and STD‐related behaviors. In general, ethnicity had little effect on the behaviors studied, especially after controlling for background variables such as socioeconomic status. However, Asians and Latinos appeared to be slightly more conservative sexually than the other groups. There is room for improvement in the sexual practices related to contraception and STDs. Anal intercourse, while not common, was far from negligible, with 14.6 percent of students having engaged in it. Condom use was low for vaginal intercourse, and even lower for anal intercourse.
Indicator Bacteria Removal in Storm-Water Best Management Practices in Charlotte, North Carolina

Water quality degradation due to pathogen pollution is a major concern in the United States. Storm-water runoff is an important contributor to the transport of indicator bacteria from urbanized wat...
Fast Fourier Transform on FCC and BCC Lattices with Outputs on FCC and BCC Lattices Respectively

In this paper, we show fast Fourier transform (FFT) algorithms for efficient, non-redundant evaluations of discrete Fourier transforms (DFTs) on face-centered cubic (FCC) and body-centered cubic (BCC) lattices such that the corresponding DFT outputs are on FCC and BCC lattices, respectively. Furthermore, for each of those FFTs, we deduce the structures of its spatial (frequency respectively) domains that are contained in the Voronoi cell centered at 0 with respect to the DFT (inverse DFT respectively) associated sublattice.
Screening with low-dose computed tomography reduced lung cancer mortality in high-risk patients

Source Citation The National Lung Screening Trial Research Team. Reduced lung-cancer mortality with low-dose computed tomographic screening. N Engl J Med. 2011;365:395-409. 21714641
The evaluation of AKR leukemia virus purity: The requirement for both velocity and isopycnic centrifugation methods

Abstract The purity of AKR murine leukemia virus obtained by isopycnic centrifugation was compared with the purity obtained by combining velocity sedimentation and isopycnic centrifugation methods. Evaluation of AKR and Rauscher viral purity by electron microscopy and by analysis of [ 3 H]uridine-labeled viral RNA demonstrated that the velocity centrifugation step is essential for the removal of contaminants banding in the viral density region (1.19 – 1.15 g/ml). For studies requiring relatively pure oncornavirus preparations, a combination of both velocity sedimentation and isopycnic centrifugation steps are suggested. Viral recovery of about 50% was obtained by the method described.
Similarity measurement for aggregation of spatial objects

SVG (Scalable Vector Graphics) is increasingly important to display multimedia data over the Internet. Although SVG is powerful in exchange, transformation, and rendering of image data, it has still the weakness of content-based component-sensitive image search mainly because it does not provide yet the descriptors of (component) image objects and their spatial relationships. Also, although similarity matches have been studied for long, similarity measurements for images that contain component image objects are not successfully developed. In this paper, we describe a new approach of a similarity measurement of aggregated image objects.
Two centuries of dance music

A Dance Pageant: Renaissance and Baroque Keyboard Dances. Selected and edited by Donald Waxman and Wendy Hilton. 80 pages. Illustrated. Boston: Galaxy Music Corporation, 1992. $15. ISBN 0–911318–18–6.
Item Response Theory Approaches to Harmonization and Research Synthesis.

The need to harmonize different outcome metrics is a common problem in research synthesis and economic evaluation of health interventions and technology. The purpose of this paper is to describe the use of multidimensional item response theory (IRT) to equate different scales which purport to measure the same construct at the item level. We provide an overview of multidimensional IRT in general and the bi-factor model which is particularly relevant for applications in this area. We show how both the underlying true scores of two or more scales that are intended to measure the same latent variable can be equated and how the item responses from one scale can be used to predict the item responses for a scale that was not administered but are necessary for the purpose of economic evaluations. As an example, we show that a multidimensional IRT model predicts well both the EQ-5D descriptive system and the EQ-5D preference index from SF-12 data which cannot be directly used to perform an economic evaluation. Results based on multidimensional IRT performed well compared to traditional regression methods in this area. A general framework for harmonization of research instruments based on multidimensional IRT is described.
Effects of cell density, temperature, and light intensity on growth and stalk production in the biofouling diatom Achnanthes longipes (Bacillariophyceae)

Achnanthes longipes Ag. is a marine stalk-forming diatom that grows in dense biofilms. The effects of cell density, temperature, and light on growth and stalk production were examined in the laboratory to determine how they affected the ability of this diatom to form a biofilm. Stalk production abruptly increased when A. longipes was cultured at a density of 5.4 × 10 3 cells.mL - 1 , with a lag before stalk production occurring in cultures initiated at lower densities. Growth occurred at all temperatures from 8 to 32° C, with maximum growth at 26° C. Growth rate was light saturated at 60 μmol photons.m - 2 .s - 1 . Stalk production was determined as the proportion of cells producing stalks and stalk length in response to various temperatures and light intensities at high (5000 cells.mL - 1 ) and low (500 cells.mL - 1 ) densities. More cells formed stalks at high density, with no difference in stalk length. The proportion of cells producing stalks was maximal at 20° C, with little change at 17-32° C. Stalk length was at a maximum between 14 and 26° C. Stalk production showed little change in response to varying light intensity. The results of an earlier investigation on the effects of bromide concentration on stalk formation were expressed as the proportion of cells forming stalks and the lengths of the stalks. Both measures of stalk production varied with bromide concentration, with maximum values at 30 mM bromide. The increased stalk production at higher densities may be a means of elevating cells above the substrate to avoid competition in the dense biofilm.
The energy distribution function associated with dubinin's description of gas adsorption on heterogeneous microporous solids

Abstract Derived here is an energy distribution function that is associated with the Gaussian distribution of micropore sizes, which was introduced by Dubinin for describing gas adsorption on heterogeneous solids with micropores only. A global energy distribution is defined for solids with both micropores and mesopores, and a method is proposed for extracting contributions to this global function arising from the non-uniform microporous structure of a solid and from the surface heterogeneity of mesopores.