cssi/SciSciGPT-SciSciNet huggingface dataset:
Leveraging big data to guide better nurse staffing strategies.

Over the past 20 years, a large body of research has documented a relationship between higher nurse-to-patient staffing ratios and better patient outcomes, including shorter hospital stays, lower rates of failure to prevent mortality after an in-hospital complication, inpatient mortality for multiple types of patients, hospital-acquired pneumonia, unplanned extubation, respiratory failure and cardiac arrest.1–5 In addition, patients report higher satisfaction when they are cared for in hospitals with higher staffing levels.6 7 To date, most studies have not identified an ‘optimal’ nurse staffing ratio,8 which creates a challenge for determining appropriate staffing levels. If increasing nurse staffing always produces at least some improvement in the quality of care, how does one determine what staffing level is best? This decision is ultimately an economic one, balancing the benefits of nurse staffing with the other options for which those resources could be used. It is in this context that hospitals develop staffing plans, generally based on historical patterns of patient acuity. Hospital staffing plans provide the structure necessary for determining hiring and scheduling, but fall short for a number of reasons. First, there are multiple ways in which patient acuity can be measured, which can have measurable effects on the staffing levels resulting from acuity models.9 Second, patient volume and acuity can shift rapidly with changes in the volume of admissions, discharges and transfers between units. Third, staffing plans provide little guidance regarding the optimal mix of permanent staff, variable staff and externally contracted staff. The paper by Saville and colleagues10 in this issue of BMJ Quality & Safety addresses the latter two issues by …
The Changing Resource Needs of New Ventures and Venture Capital Syndicate Expertise Diversity

Employing a dynamic view of the resource dependence perspective (RDP), we examine how changing resource needs of new ventures will drive lead venture capitalists (VCs) to reach other partners for h...
OutFoxed Pier son v. Post and the Natural Law

Think back to first year property class. You are a bright-eyed 1L, and one of the first cases you read deals with hunting foxes on the beaches of Long Island, New York. The fact pattern seems obscure enough, but Pierson v. Post 1 is the seminal case used to teach generations of law students about the acquisition of property.2 The interest in Pierson has recently been reinvigorated thanks to the research of Angela Fernandez in uncovering the original record of this case, as The Law and History Review dedicated an entire issue to the facts, policies, and lessons to be learned from this famous foxhunt.3 Over 200 years after Pierson v. Post was litigated in the New York Supreme Court of Judicature, this case remains an archetypal case for property students, discussing how property rights can be acquired in the absence of positive legal allocations.4 In this case,
Birth order effects on breastfeeding self-efficacy, parent report of problematic feeding and infant feeding abilities

Abstract The goal of this prospective study was to identify effects of birth order on breastfeeding self-efficacy, parental-report of infant feeding behaviors, infant non-nutritive sucking and oral feeding skills in full-term infants at 3-months. Mothers were separated into primipara and multipara groups, and infants were grouped into siblings and no siblings groups. Parents completed the Breastfeeding Self-Efficacy Scale-Short Form, and Neonatal Eating Assessment Tool–Breastfeeding and Bottle-feeding scales. Non-nutritive sucking was assessed using a custom research pacifier and researchers completed the Oral Feeding Skills scale to assess feeding performance. Fifty-six mother-infant dyads (55% male infants) were included. Primipara mothers reported significantly lower breastfeeding self-efficacy and more feeding problems across breast and bottle-feeds on the Neonatal Eating Assessment Tool. There were no significant differences in non-nutritive sucking or oral feeding skills between infant groups. First-time mothers require more feeding support as they exhibited lower breastfeeding self-efficacy and reported more problematic infant feeding behaviors.
The Property Law of Tokens

Non-fungible tokens—or NFTs, as they are better known—have taken the world by storm. The idea behind an NFT is that by owning a certain thing (specifically, a digital token that is tracked on a blockchain), one can hold property rights in something else (either a real or intangible asset). In the early part of 2021, NFTs for items ranging from a gif of a pop-tart cat with a rainbow tail, to Twitter CEO Jack Dorsey’s first tweet, to a New York Times column (about NFTs!) have sold for millions of dollars over the internet. Promoters assert that NFTs are the “future of digital property,” and that they herald a day when “government will lose its unique power to mint currency and protect property.” And these promoters reach beyond the typical crypto crowd. Giants of finance and industry are promising to extend the use of NFTs to securities, industrial assets, and real estate in the coming years. Moreover, this crypto token craze comes at a time when the American Law Institute and the Uniform Law Commission are in the midst of recommending revisions to U.S. commercial law to accommodate the digital age. In this Article, we take a more sober look at the tokenization phenomenon and, in doing so, describe what exactly it means when it comes to property rights. What can a purchaser of a token expect? How is a token actually connected to the underlying asset, if at all? What does the law—not the hype—have to say about it? We show that tokenization under the law actually has a long history, backed by practical economic considerations and animated by strong theoretical underpinnings. We also show that NFTs have neither of these attributes. Additionally, our Article surveys a dataset of terms of service from the most prominent NFT platforms in order to exploit both their disconnect from real legal effects and their puzzlingly contradictory promises about the relationships between buyers, seller, and the platform. Our project aims not only to inform current commercial law reform efforts, but it also offers a policy prescription for policing the NFT market.
Security of ramp schemes

A k out of n p/s/r process [AS81] is a very efficient way to convey information (k words suffice to reclaim k words). But it provides virtually no cryptographic security for the information it deals with.
From Tools to Glue

This paper deals with trends in computer-based product realisation, from the early focus on geometry tools to today’s focus on information infrastructure: from tools to glue. Setting the stage with a short overview of the evolution of CAD, the discussion then treats NIIIP integration protocols, and ends with the recent, big picture, Next Generation Manufacturing framework. The author had some involvement in both of these projects. These two benchmark projects characterise key issues in product realisation.
Recent studies in the economic history of medieval england: A review essay

(1992). Recent Studies in the Economic History of Medieval England. Historical Methods: A Journal of Quantitative and Interdisciplinary History: Vol. 25, No. 1, pp. 42-47.
The Process of Legal Research

Technology has created and expanded many tools for legal research. That means that selecting the best research tool for a problem is no long a matter of using the only resource published! Designing a research processor framework is one of the most important skills a legal researcher can develop. This chapter discusses integrating print and electronic tools, using a research strategy, and managing your legal research.
Paths to Citizenship: A Comparative Study of Japan, Germany and Sweden

This paper examines citizenship policy in Japan, Germany and Sweden in an attempt to explain why some rich, democratic nations have high rates of naturalization and non-restrictive paths to citizenship, while others have negligible rates of naturalization and very restrictive policies. Japan has a very restrictive policy while Sweden has a very open policy. Germany is a mid-level case that has moved from more restrictive to less restrictive over the last several years. In this paper I look at the explanatory potential of internal, institutional, and external variables. I use data from the World Values Survey to compare domestic attitudes. I look at constitutional provisions and the structure of judicial systems to compare institutional factors. I then compare regional integration and security concerns as external pressures. I conclude that cultural attitudes seem to follow, rather than precipitate, policy change, while the institutional and external factors are more promising as explanatory factors for variance in citizenship regimes.
Reproducibility of Proton MR Spectroscopic Imaging (PEPSI): Comparison of Dyslexic and Normal-Reading Children and Effects of Treatment on Brain Lactate Levels during Language Tasks

BACKGROUND AND PURPOSE: We repeated a proton echo-planar spectroscopic imaging (PEPSI) study to test the hypothesis that children with dyslexia and good readers differ in brain lactate activation during a phonologic judgment task before but not after instructional treatment. METHODS: We measured PEPSI brain lactate activation (TR/TE, 4000/144; 1.5 T) at two points 1–2 months apart during two language tasks (phonologic and lexical) and a control task (passive listening). Dyslexic participants (n = 10) and control participants (n = 8) (boys and girls aged 9–12 years) were matched in age, verbal intelligence quotients, and valid PEPSI voxels. In contrast to patients in past studies who received combined treatment, our patients were randomly assigned to either phonologic or morphologic (meaning-based) intervention between the scanning sessions. RESULTS: Before treatment, the patients showed significantly greater lactate elevation in the left frontal regions (including the inferior frontal gyrus) during the phonologic task. Both patients and control subjects differed significantly in the right parietal and occipital regions during both tasks. After treatment, the two groups did not significantly differ in any brain region during either task, but individuals given morphologic treatment were significantly more likely to have reduced left frontal lactate activation during the phonologic task. CONCLUSION: The previous finding of greater left frontal lactate elevation in children with dyslexia during a phonologic judgment task was replicated, and brain activation changed as a result of treatment. However, the treatment effect was due to the morphologic component rather than the phonologic component.
Integrating Commodity Markets in the Optimal Procurement Policies of a Stochastic Inventory System

In this paper we develop a model for the procurement of traded commodities that incorporates the market-determined term structure of commodity prices. The economic cost of holding a commodity is affected by the spread between the spot and futures prices, which varies stochastically through time; this exogenously imposed holding cost is traded against firm-specific marginal costs and benefits associated with stocking each additional unit of inventory. In addition to storage and backlogging costs, our procurement model also incorporates differential transportation costs associated with forward and spot market procurement, and it allows for selling excess inventory in spot and forward markets. We show, in a multi-period, periodic-review inventory model with stochastic non-stationary demands, that optimal forward procurement policies are characterized by a fixed band. Optimal spot procurement policies are more intricate and can be described as a regulated band. We characterize the band thresholds and develop an algorithm to obtain them by exploiting the structural properties of the optimal policy. Our results suggest that it is possible to reduce inventory related costs significantly by incorporating spot and futures price information in the procurement decision making process. Our results also imply that, apart from price-risk reduction, the potential savings in transportation costs associated with forward procurement could entice manufacturers to procure a significant fraction of goods from forward markets, using spot procurement only to fine tune stocking levels and recover from emergencies.
Energy and Communication in Three Species of Hylid Frogs: Power Input, Power Output and Efficiency

1. 1. Rates of oxygen consumption for calling, rest and locomotion were measured for three species of treefrogs from the south-east United States: Hyla cinerea (Schneider), H. gratiosa LeConte and H. squirella Bosc. 2. 2. Anaerobic metabolism was slight during calling but large during forced hopping in H. squirella . It is assumed that calling in all three species is primarily aerobic. 3. 3. For all species, oxygen consumption during calling rivalled or exceeded that for locomotion in a closed chamber. Calling apparently is at least as costly as closed-chamber locomotion, if anaerobic contributions to hopping are ignored. 4. 4. The mass-specific costs of producing calls are similar in most species of hylids whose calling energetics have been studied. 5. 5. As in other species of hylids, abdominal trunk muscle masses in male H. squirella and H. gratiosa were large - approximately 10% of the total body mass. 6. 6. Complete sound fields (with measures of variation) were mapped for each species. Each species is an essentially omnidirectional radiator with only a slight flattening of the field behind the head. 7. 7. Efficiencies of sound production (acoustic power/metabolic power) were calculated for each species and compared with values from other frogs, insects and loudspeakers. Efficiencies in hylids vary between 0.8 and 4.9%. 8. 8. Factors that contribute to determining the efficiency of sound production are reviewed. Small animals such as frogs and insects must either use low-efficiency radiators or use high-frequency sounds that do not propagate over great distances. It is possible that low-efficiency transducers maximize the area over which an animal is heard per unit of energy expended.
Toxin probes for voltage sensitive calcium channels

Toxins have proved to be essential tools in the study of the structure and function of voltage sensitive sodium channels. Several candidates for toxins that activate or block voltage sensitive calcium channels are considered here. These may provide important new data on calcium channel regulation.
The Strategic Effects of Long-Term Debt in Imperfect Competition

Abstract When rival firms issue long-term debt, their product market behavior is driven by strategic considerations that would not be present if the firms had no debt or if their debt was short term. It is shown that with limited liability, a firm′s behavior in product market competition can be strongly affected by its accumulated profits. In markets where firms choose output in every period, the higher is the firm′s profit in a given period, the less aggressive it will be in the subsequent periods. Thus, by issuing long-term debt rival firms may induce collusive behavior over some length of time. Furthermore, the path of equilibrium prices and the degree of price fluctuations may be entirely different depending on the structure of the firm′s debt. Journal of Economic Literature Classification Numbers: D43, G32.
RNA secondary structure as a reusable interface to biological information resources.

Abstract The dissemination of biological information has become critically dependent on the Internet and World Wide Web (WWW), which enable distributed access to information in a platform independent manner. The mode of interaction between biologists and on-line information resources, however, has been mostly limited to simple interface technologies such has hypertext links, tables and forms. The introduction of platform-independent runtime environments facilitates the development of more sophisticated WWW-based user interfaces. Until recently, most such interfaces have been tightly coupled to the underlying computation engines, and not separated as reusable components. We believe that many subdisciplines of biology have intuitive and familiar graphical representations of knowledge that can serve as multipurpose user interface elements. We call such graphical idioms “domain graphics”. In order to illustrate the power of such graphics, we have built a reusable interface based on the standard two dimensional (2D) layout of RNA secondary structure. The interface can be used to represent any pre-computed layout of RNA, and takes as a parameters the sets of actions to be performed as a user interacts with the interface. It can provide to any associated application program information about the base, helix, or subsequence selected by the user. We show the versatility of this interface by using it as a special purpose interface to BLAST, Medline and the RNA MFOLD search/compute engines. These demonstrations are available at: ir|url|http://www-smi.stanford.edu/projects/helix/pubs/ gene-combis-96/
ON THE LARGE DEFORMATIONS OF C-SHAPED SPRINGS

Abstract Large deflections of C- shaped springs are studied using the theory of the Elastica. The resulting nonlinear differential equation is integrated by a new homotopy method. It is found that the force-displacement curve is decidely nonlinear and depends heavily on the free shape of the spring. The maximum moment is also obtained.
Crown ethers as size-selective synergists in solvent extraction systems: A new selectivity parameter☆

Abstract Mixtures of macrocyclic polyethers (crown ethers) and organic-phase-soluble liquid cation exchangers have been found to produce a synergistic effect in the extraction of metal ions. The synergistic effect is size selective; that is, it tends to be greatest for those ions that best fit the crown ether cavity. The mixtures of a liquid cation exchanger and a crown ether also allow metal ion extraction from common mineral-acid anion systems (NO3−, Cl−, SO42−) that would be impossible with the crown ether alone, because of the difficulty of solubilizing those anions in nonpolar solvents. This cooperation makes the use of crown ethers as size-selective coordinators available for process applications. Size selectivity of compounds such as crown ethers may thus become a useful new parameter in designing selective solvent extraction systems.
Effects of Controversy on Epistemic Curiosity, Achievement, and Attitudes

Summary Comparisons were made of the effects of controversy versus no-controversy on epistemic curiosity, achievement, and attitudes of fifth- and sixth-grade Ss. Eighty Ss were assigned to conditions on a stratified random basis, with control held for class membership, reading ability, and sex. Within each condition they were assigned to groups of four on a similar stratified random basis so that there were an equal number of fifth- and sixth-grade groups, each one made up of a boy and a girl of high-reading-ability and a boy and a girl of low-reading-ability. Ss participated in two five-day instructional units, half participating in structured argumentation with their fellow group members and half discussing the material without arguing with their peers. Behavioral measures were taken on Ss' epistemic curiosity. The results indicate that controversy, compared with no-controversy, leads to more epistemic curiosity, higher achievement, and more positive attitudes.
Absorption into silicone rubber membranes from powders and aqueous solutions

Abstract This study compared the rate and amount of absorption from aqueous solutions and pure powders of 3- and 4-cyanophenol (CP) into silicone rubber (SR) membranes. SR membranes were cast directly onto a zinc-selenide attenuated total reflectance (ATR) crystal, which was then mounted on a Fourier transform infrared (FTIR) spectrometer. CP was presented to the SR membrane from aqueous solutions or powders sufficient to completely cover the membrane surface. The concentration of CP in the membrane at the interface with the crystal was determined by IR absorption of the CN stretch. The amount of CP in the SR membrane at steady state was determined by extraction and UV absorption measurements of the extract. The concentration of CP in SR membranes was found to depend weakly on the concentration of the aqueous solution. The amount of CP in SR membranes equilibrated with pure powders was essentially the same as for the CP-saturated solutions. Diffusion coefficients for 3 and 4-CP (2.8±0.2 and 2.5±0.6×10 −7 cm 2 s −1 , respectively) were not statistically different. The absorption rate of CP into SR membranes was almost the same from the powder and aqueous solution indicating that the rate of mass transfer from the powder to membrane was larger than 0.04 cm h −1 .
Perfect polar stacking of parallel beloamphiphile layers. Synthesis, structure and solid-state optical properties of the unsymmetrical acetophenone azine DCA

Extraordinary high degrees of polar order can be achieved by a rational design that involves the polar stacking of parallel beloamphiphile monolayers (PBAM). This strategy is exemplified by the acetophenone azines MCA (4-methoxy-4′-chloroacetophenone azine) and DCA (4-decoxy-4′-chloroacetophenone azine). The beloamphiphile design aims to achieve strong lateral interactions by way of arene–arene, azine–azine, arene–azine and halogen-bonding interactions. Dipole-induced interactions and halogen bonding dominate interlayer interactions and halogen bonding is shown to effect the layer stacking. Crystals of DCA contain PBAMs with perfect polar order and perfect polar layer stacking, while crystals of MCA features perfect polar order only in one of two layers and layer stacking is polar but not entirely perfect. We report the synthesis of the beloamphiphile DCA, its crystal structure, and we present a comparative discussion of the structures and intermolecular interactions of MCA and DCA. Absorbance and photoluminescence measurements have been carried out for solutions of DCA and for DCA crystals. DCA exhibits a broad emission centered at 2.5 eV when excited with UV radiation. The nonlinear optical response was studied by measuring second harmonic generation (SHG). Strong SHG signals have been observed due to the polar alignment and the DCA crystal's NLO response is 34 times larger than that of urea. Optimization of the beloamphiphile and systematic SAR studies of the polar organic crystals, which are now possible for the very first time, will further improve the performance of this new class of functional organic materials. The materials are organic semiconductors and show promise as blue emitters, as nonlinear optical materials and as OLED materials.
Morphology-dependent light trapping in thin-film organic solar cells

The active layer materials used in organic photovoltaic (OPV) cells often self-assemble into highly ordered morphologies, resulting in significant optical anisotropies. However, the impact of these anisotropies on light trapping in nanophotonic OPV architectures has not been considered. In this paper, we show that optical anisotropies in a canonical OPV material, P3HT, strongly affect absorption enhancements in ultra-thin textured OPV cells. In particular we show that plasmonic and gap-mode solar cell architectures redistribute electromagnetic energy into the out-of-plane field component, independent of the active layer orientation. Using analytical and numerical calculations, we demonstrate how the absorption in these solar cell designs can be significantly increased by reorienting polymer domains such that strongly absorbing axes align with the direction of maximum field enhancement.
Comparisons of alum-precipitated and unprecipitated aqueous ragweed pollen extracts in the treatment of hay fever.

Abstract In 1969 and 1970, groups of patients with ragweed hay fever never before treated were started on preseasonal courses of immunization with an alum precipitate of aqueous ragweed extract. A comparison between these two groups of patients and a similar group of patients treated with unprecipitated aqueous extract in 1968 shows that treatment with alum precipitate was safely initiated with fewer injections even though a higher dose was administered. The larger cumulative dose appeared to give better IgG antibody responses and greater relief of symptoms. A repeat preseasonal course the next year again required fewer injections of the alum-precipitated extract than a repeat course of aqueous extract.
Nanosecond Laser Ablation of Silicon Carbide at Infrared Wavelength

Silicon carbide, due to its unique properties, has many promising applications in optics, electronics and other areas. However, it is difficult to process using mechanical machining or electrical discharge machining due to its electrical insulation, high hardness and brittleness. Laser ablation can potentially provide a good solution for silicon carbide micromachining. However, the study on silicon carbide ablation by nanosecond laser pulses at infrared wavelength is limited, and will be presented in this paper. The laser ablation rate, laser-induced plasma, the ablated surface morphology and chemical composition change have been studied, and the results are discussed.© 2010 ASME
Fluorescence studies on deuterated Chlorella vulgaris

Abstract Chlorella vulgaris grown in 99.8% heavy water show absorption spectra similar to the absorption spectra shown by those grown in ordinary water; there appears to be a minor shift of about 1 mμ towards shorter wavelengths in the blue and the red absorption bands, and a slight increase in chlorophyll b to a and carotenoids to chlorophyll a ratios in the heavy-water cells. Fluorescence (emission) spectra of deuterated Chlorella show an emission peak which is shifted about 2.0 mμ towards shorter wavelengths. In addition, the ratio of fluorescence at the main peak to fluorescence at 730 mμ is lower in the heavy-water cells, suggesting that they might have more of chlorophyll a 1 fluorescence. The yield of fluorescence is about 20–30% higher in deuterated Chlorella (measured at the emission peak). The excitation spectra of fluorescence show that the energy transfer from chlorophyll b to chlorophyll a 670 is almost 100% in both deuterated and ordinary hydrogen cells.
SU-E-J-59: Dual Imaging Guided Localization System for Spine Radiosurgery.

Purpose: To compare localization accuracies between an ExacTrac and cone beam computed tomography(CBCT) systems for single fraction spine adiosurgery. The work also aimed to evaluate the inherent systematic deviation of both ExacTrac and CBCT systems to achieve highly accurate localization in the spine radiosurgery.Methods: ExacTrac and CBCTimaging systems were evaluated using the linac isocenter as the mutual reference point. First, a BB was placed in an anthropomorphic pelvic phantom. The phantom was localized with both imaging systems and the procedure was repeated 12 times. These results were used to devise a localization protocol using both imaging systems in spine radiosurgery, and employed for 51 patients (81 isocenters) prescribed for single fraction treatment. The displacement discrepancy between the isocenter and two systems were quantified in four dimensions (three translations, one rotation). A Student's two‐tailed t‐test was used to test for significant differences between the two imaging systems. Results: The phantom study showed 1.4±0.5, 0.6±0.5, and 0.1±0.5 mm differences between the two imaging systems in the anterior/posterior (A/P), superior/inferior (S/I) and left/right (L/R) directions, respectively. The angular difference was minimal along all three axes. The patient study revealed similar isocenter discrepancies between ExacTrac and CBCT of 1.1 ± 0.7 mm, 1.0±0.9 mm, and 0.2±0.9 mm in the A/P, S/I, and L/R directions, respectively, with the A/P and S/I directions showing statistical significance ((t(80) = 13.5 and 7.6 respectively, p = 0.000). The couch yaw discrepancy was 0 ± 0.3°. Overall, 1 mm systematic differences were observed in the A/P and S/I directions between ExacTrac and CBCT localization systems, both in phantom and patient. A procedure was developed to mitigate this systematic discrepancy. Conclusions: These findings have justified our patient localization tolerance levels of 2 mm translation and 1 degree rotation for spine SRS treatment.
Correction: Pyridine synthesis from oximes and alkynes via rhodium(III) catalysis: Cp* and Cp(t) provide complementary selectivity.

The synthesis of pyridines from readily available α,β-unsaturated oximes and alkynes under mild conditions and low temperatures using Rh(III) catalysis has been developed. It was found that the use of sterically different ligands allows for complementary selectivities to be achieved.
L 1 adaptive controller for MIMO systems with unmatched uncertainties using modified piecewise constant adaptation law

This paper presents the L 1 adaptive controller for a class of multi-input multi-output (MIMO) systems with both matched and unmatched nonlinear uncertainties. A modification of the piecewise constant adaptive law is introduced based on the history of the past samples. Compared with the standard L 1 adaptive law with piecewise constant adaptive law, here the performance bounds decay much faster as the sample period decreases, yielding better performance at a given sample period, or less stringent requirements on the computation and measurement frequency for a given performance level. Simulation results verify the theoretical findings.
HMG 14 and protamine enhance ligation of linear DNA to form linear multimers: phosphorylation of HMG 14 at Ser 20 specifically inhibits intermolecular DNA ligation.

HMG 14 and protamine can be used to enhance intermolecular ligation of low concentrations of linear DNA. Adding HMG 14 (50 moles per mole DNA) caused 50% of blunt-ended DNA to form predominantly dimers, and all cohesive-ended DNA to form multimers (>6-mer) in response to T4 ligase. Protamine was maximally effective at 40:1, producing mostly dimers and trimers. Adding higher concentrations of HMG 14 did not affect the ligation pattern of cohesive-ended DNA, while higher concentrations of protamine inhibited the formation of multimers. Phosphorylation of HMG 14 at Ser 20 by Ca++-phospholipid dependent protein kinase abolished the ability of HMG 14 to stimulate intermolecular ligation, but did not substantially interfere with intramolecular ligation, or the binding of HMG 14 to linear or circular DNA as assessed by gel mobility. Thus Ser 20, which is located in the amino terminal DNA-binding domain of HMG 14, appears to modulate DNA-DNA interactions.
TH-C-BRB-05: Status of the NIST Primary Standard Water Calorimeter for 60Co Beams

Purpose: Validation of a second‐generation primary standard water calorimeter for use in 60Co radiation beams. Method and Materials: Work on a second‐generation water calorimeter at NIST has progressed to a stage in which extensive comparison tests are being conducted with a transfer chamber connecting the historical value determined by Steve Domen. The present water calorimeter based upon Domen's original design consists of a thin‐walled cylindrical glass vessel of ∼2 cm radius and ∼12 cm length with two thermistor probes mounted along the axis. The response of the thermistors which are wired into opposite arms of a Wheatstone bridge is measured with a lock‐in amplifier (LIA). The calorimeter situated at 5 cm depth in a water phantom at various SDD (77.4 cm and 100.0 cm) is subject to periodic 70s radiation exposures from a vertical 60Co radiation beam and its steady‐state response is obtained both by Fourier analysis and midpoint extrapolation of the time waveform obtained from the LIA. A separate vessel of similar but not identical dimensions containing a calibrated Farmer chamber then replaces the thermistor system to obtain a dose rate under identical conditions. Results: Agreement between chamber and calorimeter estimates of dose is within 0.4% for SDD of 77.4 cm and 0.13% at 100 cm. At 77.4 cm dependence on spatial variations due to possible nonuniformities in the beam were faithfully replicated by the thermistor system however the latter estimates of dose rate were lower in all cases. At 100 cm there is no spatial dependence and no evidence of systematic error. Conclusion: The differences between calorimeter and transfer standard were within the 1 sigma statistical uncertainty of+/− 0.13% at 1 m; consistency of the new calorimeter with the historical value is obtained. Reproducibility and possible corrections are needed before the primary standard can be reestablished.
Evaluation of catalysts and membranes for high yield biohydrogen production via electrohydrogenesis in microbial electrolysis cells (MECs).

Hydrogen gas can be produced from fermentation end products such as acetic acid through the electrohydrogenesis process in microbial electrolysis cells (MECs). In many MEC reactors, precious metal catalysts and expensive cation exchange membranes are often used. Here we examine Co- and FeCo-based alternatives to Pt, and compare the performance of an anion exchange membrane with that of a cation exchange membrane (Nafion™ 117). It is found that these alternative catalysts have 40–80% better performance than uncatalysed surfaces, but they do not equal the performance of Pt based on our electrochemical tests using cyclic voltammetry. It was also found that the anion exchange membrane (AEM) performance was equal to that of cation exchange membrane (CEM) at applied voltages of 600 mV or less in MEC tests, but that it exceeded performance of the CEM at voltages above 600 mV. These results demonstrate choosing catalysts will require both analysis of performance and materials costs, but that performance is improved for producing H 2 gas in MECs using AEMs.
Lung dose, distribution, and clinical response to therapeutic aerosols

The response to therapeutic aerosols is considered to be a function of the dose deposited at the target site in the lung. The dose, in turn, is dependent upon the system producing the aerosol, the particle size characteristics of the inhaled aerosol, the mode of inhalation, and the calibre of the airways. The influence of the pattern of deposition of the inhaled dose, i.e., selective delivery to the central vs. small, peripheral airways, on the response is not as well defined. Distribution of therapeutic aerosols in the lung has been measured using a variety of tracer methods; correlations with clinical response have been obtained in a limited number of these same studies. Systems used to provide unit doses of therapeutic aerosols are the metered dose inhaler (MDI), containing drug in a pressurized formulation, and the dry powder inhalers (DPI). Efficiency of delivery is on the order of 5–15% for these systems, even under optimal inhalation conditions. Continuous aerosol is provided by the jet or ultrason...
Phosphodiesterase activity in pupae and diapausing and non-diapausing larvae of the European corn borer, Ostrinia nubilalis

Abstract Phosphodiesterase activity was higher in crude fractions of homogenates prepared from pupae and non-diapausing larvae of the European corn borer, Ostrinia nubilalis than in those from diapausing larvae, but little difference was observed in the diesterase activity of third, fourth, and fifth instar larvae. Inhibition of the activity was achieved with caffeine (0·008 M) or theophylline (0·008 M) which are usually considered inhibitors of cyclic 3′,5′-nucleotide phosphodiesterases. Although the haemolymph contained some phosphodiesterase activity, the amount found did not account for all the activity exhibited by the 105,000 g supernatant fraction prepared from whole insects. However, the phosphodiesterase activity exhibited by the gut of developing larvae accounted for about half of the activity.
Mössbauer spectra, magnetic and electrical behavior of Ba1+xFe2S4 phases

Abstract The Mossbauer spectra, and magnetic and electrical properties of Ba1+xFe2S4 infinitely adaptive phases with 0.074 ≤ x ≤ 0.142 and of BaFe2S4 were studied. The properties are highly anisotropic because of the presence in the structure of one-dimensional infinite chains of edge sharing FeS4 tetrahedra. BaFe2S4 is a semiconductor, Eg = 0.66 eV; magnetic susceptibility can be fit by a one-dimensional Heisenberg model with spin 5 2 and J k = −30° K . The Ba1+xFe2S4 phases have Curie-Weiss behavior with an effective moment of about 2 B.M. The moment increases with x. These phases are metallic. The Mossbauer isomer shift varies linearly with valence, increasing with increasing x. The single quadrupole split absorption line characteristic of these compounds disappears at about 270°K and a complex spectrum consisting of overlapping hyperfine patterns appears at lower temperatures. Magnetic short-range ordering is responsible for this behavior although the susceptibility in this temperature range does not reflect this effect.
RESET for quantile regression

This paper proposes a simple specification test for quantile regression models. Our test is based on Ramsey’s (J. R. Stat. Soc. B 31:350–371, 1969) RESET (regression specification error test). Comparing to existing nonparametric specification tests, the proposed test does not contain kernel functions and bandwidth parameters and is easy to implement. Although the proposed test is not necessarily consistent against all types of misspecification, simulation results indicate that our test has reasonable size and power properties and can be more powerful than nonparametric specification tests in small samples.
Persistence after birth of systemic inflammation associated with umbilical cord inflammation

Intrauterine inflammation is followed by elevated concentrations of inflammation-related proteins in the newborn's blood. Many of these proteins have short half-lives. The persistence of this postnatal inflammation has not previously been investigated. In a sample of 834 infants born before the 28th week of gestation, 12% (103) had grade 1 or 2, and 17% (142) had grade 3, 4, or 5 umbilical cord inflammation. Concentrations of nine proteins previously shown to be associated with umbilical cord inflammation at birth were measured on the first postnatal day and at two weekly intervals after birth. We evaluated the hypothesis that children who had umbilical cord inflammation were no more likely than others to have elevated concentrations of inflammation-related proteins in postnatal blood. The concentrations of seven of the nine proteins [C-reactive protein (CRP), myeloperoxidase (MPO), IL1β, IL8, TNFα, intercellular adhesion molecule-1 (ICAM3), and matrix metalloproteinase (MMP9)] showed a tendency to be elevated on day 7 among infants with funisitis. Adjusting for gestational age, growth restriction, and three postnatal exposures (ventilation on day 7, presumed and definite early bacteremia, and Bell stage III necrotizing endocolitis) did not diminish the elevated odds ratios of concentrations in the top quartile (for gestational age and day the specimen was obtained) of MPO, IL1β, TNFα, IL8, ICAM3, and MMP9. The persistence of a relationship between umbilical cord inflammation and elevated blood concentrations of inflammation-related proteins on postnatal day 7 suggests the existence of phenomena that contribute to a reinforcement loop and thereby sustained systemic inflammation.
Killing tumours by ceramide-induced apoptosis: a critique of available drugs

Over 1000 research papers have described the production of programmed cell death (apoptosis) by interventions that elevate the cell content of ceramide (Cer). Other interventions, which lower cellular Cer, have been found to interfere with apoptosis induced by other agents. Some studies have shown that slowing the formation of proliferation-stimulating sphingolipids also induces apoptosis. These relationships are due to the two different aspects of Cer: Cer itself produces apoptosis, but metabolic conversion of Cer into either sphingosine 1-phosphate or glucosphingolipids leads to cell proliferation. The balance between these two aspects is missing in cancer cells, and yet intervention by stimulating or blocking only one or two of the pathways in Cer metabolism is very likely to fail. This results from two properties of cancer cells: their high mutation rate and the preferential survival of the most malignant cells. Tumours treated with only one or two drugs that elevate Cer can adjust the uncontrolled processes to either maintain or to 'aggravate' the excessive growth, angiogenesis and metastasis characteristics of tumours. These treatments might simply elevate the production of growth factors, receptors and other substances that reduce the effectiveness of Cer. Tumour cells that do not adapt in this way undergo apoptosis, leaving the adapted cells free to grow and, ultimately, to 'subdue' their host. Thus it is important to kill every type of cancer cell present in the tumour rapidly and simultaneously, using as many different agents to control as many pathways as possible. To aid this approach, this article catalogues many of the drugs that act on different aspects of Cer metabolism. The techniques described here may lead to the development of practical chemotherapy for cancer and other diseases of excess proliferation.
A universal criterion for plastic yielding of metallic glasses with a (T/Tg) 2/3 temperature dependence.

Room temperature (TR) elastic constants and compressive yield strengths of ~30 metallic glasses reveal an average shear limit gammaC=0.0267±0.0020, where tauY=gammaCG is the maximum resolved shear stress at yielding, and G the shear modulus. The gammaC values for individual glasses are correlated with t=TR/Tg, and gammaC for a single glass follows the same correlation (vs t=T/Tg). A cooperative shear model, inspired by Frenkel's analysis of the shear strength of solids, is proposed. Using a scaling analysis leads to a universal law tauCT/G=gammaC0-gammaC1(t)2/3 for the flow stress at finite T where gammaC0=(0.036±0.002) and gammaC1=(0.016±0.002).
Mandelstam representation for the nonrelativistic many channel problem

Abstract In this paper we investigate the analytic properties of the transition amplitudes for the collision of two particles each capable of a number of excited states and interacting through a set of generalized Yukawa potentials. Double dispersion relations for each of the amplitudes can be derived only when the reduced mass is the same for all channels and a certain stability condition, which ensures the absence of anomalous thresholds, is satisfied. The Mandelstam representation is then discussed in connection with unitarity and the partial wave expansion is obtained with results similar to the one-channel case.
Optimal placement of reconfigurable optical add/drop multiplexers with packing, blocking, and signal loss

With technological and manufacturing advances, and increased economies of scale, today the use of Reconfigurable Optical Add/Drop Multiplexers (ROADMs) has become economical. A ROADM allows individual or multiple wavelengths to be added and/or dropped from a transport fiber without the need to convert the signals to electrical and back again to optical. This feature makes a fiber optic network more flexible, i.e., the network can be remotely configured/reconfigured through ROADMs. Consequently, due to high capital cost, to determine an optimal placement of ROADMs and to assign wavelengths in a cost efficient way becomes an important problem in network topology design. We introduce a Mixed Integer Programming model that captures signal loss and wavelength packing/blocking, and develop a three-phase algorithm to efficiently solve it. Analytical justifications for the algorithmic steps are provided. Computational experiments are conducted to assess the tractability of the model, and to evaluate the performance of the proposed approach. The execution times of the algorithm are acceptable.
The role of thermals in the convective boundary layer

Detailed measurements of the structure of thermals throughout the convective boundary layer were obtained from the NCAR Electra aircraft over the ocean during the Air Mass Transformation Experiment (AMTEX). Humidity was used as an indicator of thermals. The variables were first high-pass filtered with a 5 km cutoff digital filter to eliminate mesoscale variations. Segments of the 5 min (30 km length) horizontal flight legs with humidity greater than half the standard deviation of humidity fluctuations for that leg were defined as thermals. This was found to be a better indicator of thermals than temperature in the upper part of the boundary layer since the temperature in a thermal is cooler than its environment in the upper part of the boundary layer. Using mixed-layer scaling, the normalized length and number of thermals were found to scale with the 1/3 and -1/3 powers, respectively, of normalized height, while vertical velocity and temperature scaled according to similarity predictions in the free convection region of the surface layer. The observational results presented here extend throughout the entire mixed layer. Using these results in the equation for mean updraft velocity of a field of thermals, the sum of the vertical pressure gradient and edge-effect terms can be estimated. This residual term is found to be important throughout most of the boundary layer. The magnitude of the divergence of vertical velocity variance within a thermal is found to be larger than the magnitude of the mean updraft velocity term throughout most of the mixed layer.
A computational infrastructure for grid-based asynchronous parallel applications

C o n t e n t b a s e d R o u t i n g S e l f o r g a n i z i n g O v e r l a y C o o r d i n a t i o n L a y e r A p p l i c a t i o n L a y e r
Re-evaluation of the Lysine Requirement of the Commercial Laying Hen in a Corn-Soybean Meal Diet

Abstract Faria, D.E., Harms, R.H., Antar, R.S. and Russell, G.B. 2003. Re-evaluation of the lysine requirement of the commercial laying hen in a corn-soybean meal diet. J. Appl. Anim. Res., 23: 161–174. Two experiments were conducted with Hy-Line W56® hens to evaluate their Lys requirement in a corn-soybean meal diet. Eight experimental diets were used in each experiment with graded levels of Lys: 0.76, 0.72, 0.68, 0.64, 0.60, 0.56, 0.52, 0.48per cent and 0.80, 0.76, 0.72, 0.68, 0.64, 0.60, 0.56, 0.52 per cent for Experiments 1 and 2, respectively. Supplemental amino acids (AA) were added to all diets to ensure that Lys was the first-limiting AA. Egg production (EP), egg content (EC) and daily Lys intake were significantly increased with increasing dietary Lys levels. Broken-line regression indicated a daily Lys requirement of 633.1 and 642.9 mgper hen per d in Experiment 1 and of 606.5 and 606.6 mg per hen per d in Experiment 2 for EP and EC, respectively. The Lys requirements to produce a g of EC were 1...
Effect of Transpiration on Plant Accumulation and Translocation of PPCP/EDCs

The reuse of treated wastewater for agricultural irrigation in arid and hot climates where plant transpiration is high may affect plant accumulation of pharmaceutical and personal care products (PPCPs) and endocrine disrupting chemicals (EDCs). In this study, carrot, lettuce, and tomato plants were grown in solution containing 16 PPCP/EDCs in either a cool-humid or a warm-dry environment. Leaf bioconcentration factors (BCF) were positively correlated with transpiration for chemical groups of different ionized states (p < 0.05). However, root BCFs were correlated with transpiration only for neutral PPCP/EDCs (p < 0.05). Neutral and cationic PPCP/EDCs showed similar accumulation, while anionic PPCP/EDCs had significantly higher accumulation in roots and significantly lower accumulation in leaves (p < 0.05). Results show that plant transpiration may play a significant role in the uptake and translocation of PPCP/EDCs, which may have a pronounced effect in arid and hot climates where irrigation with treated wastewater is common.