cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of regenerator positioning on thermoacoustic effect in a looped tube traveling wave thermoacoustic engine

Abstract This paper discusses the effect of regenerator positioning on the intensity of the thermoacoustic effect in a looped-tube traveling wave thermoacoustic engine (TAE). Traveling wave thermoacoustic engines work on the principle of the acoustic wave moving through the loop of the engine, across the regenerator, with the pressure and velocity curves in phase, amplifying the acoustic effect. Increasing the intensity of the effect, while keeping the energy input the same increases the efficiency of the TAE, and can be further applied in a thermoacoustic refrigeration system to increase the COP. The intensity of the effect in relation to the positioning of the regenerator, also called a stack in standing wave devices, is proven here to have an optimum positioning inside of the straight part of the loop. The increase in intensity under constant heat input proves an increase in efficiency.
A survey on the assessment of wind energy potential in Egypt

In this paper, wind data obtained from the Egyptian Meteorological Authority are used to assess monthly and annual wind power and wind energy. The study is based on data from 15 anemometer meteorological stations, distributed all over Egypt and covering a period ranging from 1973 to 1994. For these stations the wind data are summarized. The wind energy potential at the 25 m height was obtained by extrapolation of data at 10 m using a power-law expression. The result presents the mean wind energy density estimates and potential for application in Egypt. The analysis showed that along Red Sea coasts, the annual wind energy flux is found to be high, which indicates that these coastal stations are possible locations for wind energy utilization. On both the Mediterranean coast and in the interior parts of Egypt, some stations are of low available wind energy, while others are found to be rather high. Also, the two Weibull distribution parameters have been estimated from the wind speed data for some meteorological stations and the wind power density is calculated using the values of these parameters.
Nutritional aspects of non-prey foods in the life histories of predaceous Coccinellidae

Non-prey foods are an integral component of the diets of most predaceous coccinellids. Under field conditions, numerous coccinellids consume nectar, honeydew, pollen, fruit, vegetation, and fungus. These non-prey foods are used by coccinellids to increase survival when prey is scarce, reduce mortality during diapause, fuel migration, and enhance reproductive capacity. Each of these non-prey foods has unique nutritional and defensive characteristics that influence its suitability for lady beetles. Quantitatively, nutrient and energy contents of these foods are often competitive with, or even exceed that, present in prey. Meta-analyses of literature were used to assess whether (1) some non-prey foods and prey are equivalent foods for coccinellids, and (2) prey-only diets and mixed diets involving prey and non-prey foods are equally suitable for coccinellids. Response variables were categorized as larval performance (e.g., development time, weight at eclosion), adult performance (e.g., adult longevity, weight change), and reproduction (e.g., fecundity, oviposition period). The analyses revealed that pollen is inferior to prey for supporting larval and adult performance, but that adult performance in sugar-fed adults was equal to that of prey-fed adults (although sugar alone does not support reproduction). Larval performance was enhanced substantially when they were reared on mixed diets compared to prey-only diets. Adding sugar to mixed diets strongly improved adult performance and reproduction over prey-only diets, but this was not the case with pollen in mixed diets. These results suggest that coccinellid larvae have more stringent nutritional requirements than adults, and that non-prey foods provide unique nutrients that enhance prey-only diets. Moreover, it suggests that simple carbohydrates are important dietary constituents capable of enhancing both adult performance and reproduction, although it is important to note that a range of prey species of variable quality for coccinellids are evaluated in this database. The literature review presented here suggests that non-prey foods are a critical component of coccinellid nutritional ecology, and may influence the success of conservation biological control programs.
Toward a General Model of Consumer Empowerment and Welfare in Financial Markets with an Application to Mortgage Servicers

Policy makers and consumer advocates suggest that mortgage servicers are prone to mistakes and predatory practices that negatively impact consumer financial well-being. Using this industry as a case study, a general model of consumer empowerment and welfare is developed integrating theoretical concepts related to market structure, firm orientation, and consumer information processing. The model illuminates the most distinctive characteristics of mortgage servicing: high switching costs faced by consumers and mortgage servicers’ inability to negotiate with some borrowers. Additionally, the model posits that the most common remedy in the financial services industry, information disclosure, is unlikely to directly improve consumer welfare.
Sol-gel process for the preparation of fine electroceramic powders

Abstract The versatility of sol-gel processing in the preparation of fine ceramic powders has been extended to technologically important electroceramic powders such as Pb(Mg1/3Nb2/3)O3, YBa2Cu3O7-x and fresnoite. Fine (<0.2μm) powders in these systems were obtained at temperatures as low as ∼750°C through the sol-gel processing.
Erosion resistance of superalloys and different coatings exposed to particulate flows at high temperature

Abstract The design and development of high performance turbomachinery operating in an ambient with solid particles require a thorough knowledge of the fundamental phenomenon associated with particulate flows. Because of the serious consequences of turbomachinery erosion on their performance and life, it is important to have reliable methods for predicting their erosion when solid particles are ingested with the incoming flow. Several studies, which are essential to predicting blade surface erosion intensity and pattern, have been conducted at the University of Cincinnati's Propulsion Laboratory over the past 25 years. This paper describes only some of the work done on erosion testing at high temperatures and velocities for different materials and coatings. The testing has been performed with a special high temperature erosion wind tunnel, which simulates the aerodynamic conditions on the blades. The coatings investigated are produced by chemical vapor deposition (CVD), physical vapor deposition (PVD), and other methods. Experimental studies were conducted at the University's high temperature erosion wind tunnel to investigate the erosion behavior of coatings exposed to different types of solid particles. Some of the following coatings were evaluated: rhodium platinum aluminized, SDG-2207 (super D-gun product), CVD coatings, including TiC, TiN, Al2O3 and PVD coatings. The erosive wear of the samples was studied experimentally by exposing them to a particle-laden flow at velocities from 180 to 305 m s−1, temperatures from ambient to 815°C and impingement angles from 15 to 90°.
Magnetic excitations in metalloporphyrins by inelastic neutron scattering: determination of zero-field splittings in iron, manganese, and chromium complexes.

Zero field splitting (ZFS) parameters of several nondeuterated metalloporphyrins [M(TPP)Cl] and [Mn(TPP)] (H2TPP = tetraphenylporphyrin) have been directly determined by inelastic neutron scattering (INS). The ZFS values are the following: D = 6.33(8) cm–1 for [Fe(TPP)Cl], −2.24(3) cm–1 for [Mn(TPP)Cl], 0.79(2) cm–1 for [Mn(TPP)], and |D|= 0.234(12) cm–1 for [Cr(TPP)Cl]. The work shows that compounds with magnetic excitations below ∼30 cm–1 could be determined using nondeuterated samples.
The radiology assistant: a contrarian’s view

Recent and rapid increases in the utilization of diagnostic imaging have not been matched by concomitant additions to the supply of radiologists and radiology technologists. One proposal to alleviate an expected worsening of this emerging workforce crisis is to create a new job category, the radiology assistant (RA), encompassing a roster of enhanced capabilities that would allow the radiologists to divest themselves of some of their non-interpretative duties with respect to the performance of imaging tests. Through the collaborative efforts of the American College of Radiology and the American Society of Radiology Technologists a nationally recognized, baccalaureate-level curriculum has been designed for the training of RAs. A centerpiece of the curriculum is instruction in fluoroscopy. However, examinations of the GI tract by fluoroscopy are rapidly declining in frequency, raising doubt about the enhanced value an RA would bring to a radiology practice in the near future and worries about encroachment on the range of radiologists' responsibilities over the long term.
dMT: inexpensive throughput enhancement in small-scale embedded microprocessors with differential multithreading

The authors examine differential multithreading (dMT) as an attractive organisation for increasing throughput in simple, small-scale, pipelined processors like those used in embedded environments. dMT copes with pipeline stalls due to hazards and data- and instruction-cache misses by using duplicated pipeline registers to run instructions from an alternate thread. Results show that dMT boosts throughput substantially and can in fact replace dynamic branch prediction or can be used to reduce the sizes of the instruction and data caches.
Sunday Friends: The Working Alternative to Charity

This research presents results from the 2009 and 2011 evaluations of a biweekly program offered by Sunday Friends, a nonsectarian, nonprofit organization in Santa Clara County, California. The cent...
Lack of catabolite regulation of NAD-glutamate dehydrogenase in an ochratoxin A-producing strain ofAspergillus ochraceus

Abstract Mycelial extracts of an ochratoxin A-producing strain and a nonproducing strain of Aspergillus ochraceus contained NAD-specific and NADP-specific glutamate dehydrogenases (GDH). The culture of these fungi on a medium containing glutamate and sucrose established that during the synthesis of the mycotoxin, the specific activity of the NADP-GDH in both strains increased along with the growth of the culture. After 6 days of growth, the NADP-GDH in the nonproducing strain declined while the NAD-GDH increased. The specific activity of NAD-GDH in the producing strain did not increase, but remained consistently low throughout the fermentation. The specific activity of NADP-GDH in the producing strain remained high throughout the production of the mycotoxin. In both strains NADP-GDH was subject to catabolite derepression or induction. The NAD-GDH from extracts of the nonproducing strain was subject to catabolite repression, whereas the NAD-GDH from the producing strain was not subject to catabolite repression and glutamate derepression. All attempts at derepressing the enzyme in this latter strain failed.
26-Desmethyl-2-methylene-22-ene-19-nor-1α,25-dihydroxyvitamin D3 compounds selectively active on intestine

Six new analogs of 2-methylene-19-nor-1α,25-dihydroxyvitamin D3, 6–7 and 8a,b–9a,b, have been synthesized. All compounds are characterized by a trans double bond located in the side chain between C-22 and C-23. While compounds 6 and 7 possess C-26 and C-27 methyls, compounds 8a,b and 9a,b lack one of these groups. A Lythgoe-based synthesis, employing the Wittig–Horner reaction was used for these preparations. Two different types of Δ22E-25-hydroxy Grundmann’s ketone, having either only one stereogenic center located at position C-20 (20 and 21), or two stereogenic centers located at 20- and 25-positions (24a,b–25a,b) were obtained by a multi-step procedure from commercial vitamin D2. The introduction of a double bond at C-22 appeared to lower biological activity in vitro and in vivo. Further removal of a 26-methyl in these analogs had little effect on receptor binding, HL-60 differentiation and CYP24A expression but markedly diminished or eliminated in vivo activity on bone calcium mobilization while retaining activity on intestinal calcium transport.
Factors Associated with the Integrated Educational Placement of Students with Severe Disabilities.

A study, using survey methodology, was conducted to identify factors associated with the integrated educational placement of students with severe disabilities. Questionnaires were completed by the families and teachers of 1,009 students from five participating states. The questionnaires were designed to measure 19 variables that integration literature suggests are predictive of integrated placement. Logistical regression procedures were utilized to determine the probability of integrated placement as a function of the identified variables, which included characteristics of the student, family, school program, and community. A stepwise procedure was employed to examine three theoretical models of variables associated with integrated placement, representing integration advocacy, socioeconomic status, and program/facilities characteristics. Additionally, a combined model was estimated using the strongest predictors from the three theoretical models. Factors identified within each of the models are discussed ...
Post-fire spatial heterogeneity alters ground-dwelling arthropod and small mammal community patterns in a desert landscape experiencing a novel disturbance regime

Anthropogenic activities have resulted in novel disturbance regimes which have unknown impacts on biodiversity. A notable example is the establishment of fire regimes in ecosystems that have not historically burned. These new disturbance regimes leave behind a complex spatial matrix with varying patterns of landscape heterogeneity. Research on novel disturbance regimes often ignores remnant vegetation within disturbed habitats, even though landscape variation in a disturbed area can influence population and community dynamics. Our objective was to understand the influence of spatial heterogeneity, characterized by varying levels of isolation and remnant vegetation, within a landscape disturbed by a novel fire regime in the Mojave Desert where wildfire was exceedingly rare to non-existent in this landscape prior to recent times. We found that community patterns of both ground-dwelling arthropods and small mammals varied based on the amount of remnant vegetation and isolation levels within burned habitats. Ground-dwelling arthropod abundance and richness measurements were highest in burned habitats that had remnant long-lived vegetation present, whereas small mammal abundance and richness measurements were highest in continuous expanses of unburned habitat. We also found that the negative impacts of fire on arthropods and small mammal communities in isolated, burned habitats were masked by the presence of long-lived perennial vegetation. Our study highlights the importance of incorporating habitat heterogeneity into future studies of novel disturbance regimes and provides evidence for the utility of restoration plantings in desert ecosystems.
Gas—liquid equilibria in ternary mixtures of hydrogen + methane + 1-methylnaphthalene at elevated temperatures and pressures

Abstract Gas—liquid equilibria in ternary mixtures of hydrogen + methane + 1-methylnaphthalene were investigated at two temperatures 542 and 704 K and at pressures from 50 to 250 atm. Relative concentration of hydrogen to methane was varied, and three observations made at each condition of temperature and pressure. The response of the K -values to changing compositions was determined.
Involvement of the Src Homology 2-containing Tyrosine Phosphatase SHP-2 in Growth Hormone Signaling

Growth hormone (GH) signaling requires activation of the GH receptor (GHR)-associated tyrosine kinase, JAK2. JAK2 activation by GH is believed to facilitate initiation of various pathways including the Ras, mitogen-activated protein kinase, STAT, insulin receptor substrate (IRS), and phosphatidylinositol 3-kinase systems. In the present study, we explore the biochemical and functional involvement of the Src homology 2 (SH2)-containing protein-tyrosine phosphatase, SHP-2, in GH signaling. GH stimulation of murine NIH 3T3-F442A fibroblasts, cells that homologously express GHRs, resulted in tyrosine phosphorylation of SHP-2. As assessed specifically by anti-SHP-2 coimmunoprecipitation and by affinity precipitation with a glutathione S-transferase fusion protein incorporating the SH2 domains of SHP-2, GH induced formation of a complex of tyrosine phosphoproteins including SHP-2, GHR, JAK2, and a glycoprotein with properties consistent with being a SIRP-alpha-like molecule. A reciprocal binding assay using IM-9 cells as a source of SHP-1 and SHP-2 revealed specific association of SHP-2 (but not SHP-1) with a glutathione S-transferase fusion incorporating GHR cytoplasmic domain residues 485-620, but only if the fusion was first rendered tyrosine-phosphorylated. GH-dependent tyrosine phosphorylation of SHP-2 was also observed in murine 32D cells (which lack IRS-1 and -2) stably transfected with the GHR. Further, GH-dependent anti-SHP-2 coimmunoprecipitation of the Grb2 adapter protein was detected in both 3T3-F442A and 32D-rGHR cells, indicating that biochemical involvement of SHP-2 in GH signaling may not require IRS-1 or -2. Finally, GH-induced transactivation of a c-Fos enhancer-driven luciferase reporter in GHR- and JAK2-transfected COS-7 cells was significantly reduced when a catalytically inactive SHP-2 mutant (but not wild-type SHP-2) was coexpressed; in contrast, expression of a catalytically inactive SHP-1 mutant allowed modestly enhanced GH-induced transactivation of the reporter in comparison with that found with expression of wild-type SHP-1. Collectively, these biochemical and functional data imply a positive role for SHP-2 in GH signaling.
Can a pulse excitation smaller than kT be detected

A ‘1kT-pulse’ excitation of a high-Q-factor LC ringing circuit is defined, and a filter configuration is described which allows the detection of such a pulse with good s.n.r. (signal/noise ratio) and excellent τr, (resolving time). S.N.R.s considerably larger than unity were found experimentally, in reasonable agreement with theoretical calculations.
The specification of program flow in Madcap 6

The control structures of the Madcap language have evolved to a point where today those of Madcap 6 have obviated programmer defined labels and go-to statements. The benefits of the removal of these concepts are discussed in detail. Madcap has a powerful class of data structures, including sets, sequences, and expressions, along with a full array of operators for manipulating these structures. These operators include important facilities for forming sets and for forming and concatenating sequences, based on very general iterative expressions. Procedures in Madcap are expressions whose evaluation is deferred; characteristics of this approach are discussed. Also described is a notation which facilitates backtrack programming.
Can Caffeine Antagonize Alcohol-Induced Performance Decrements in Humans?:

Design aspects and results of experiments that investigated the effects of caffeine on alcohol-induced performance decrements in humans are discussed. Simple conclusions concerning those outcomes a...
A Data Processing Pipeline for Mammalian Proteome Dynamics Studies Using Stable Isotope Metabolic Labeling

In a recent study, in vivo metabolic labeling using 15N traced the rate of label incorporation among more than 1700 proteins simultaneously and enabled the determination of individual protein turnover rate constants over a dynamic range of three orders of magnitude (Price, J. C., Guan, S., Burlingame, A., Prusiner, S. B., and Ghaemmaghami, S. (2010) Analysis of proteome dynamics in the mouse brain. Proc. Natl. Acad. Sci. U. S. A. 107, 14508–14513). These studies of protein dynamics provide a deeper understanding of healthy development and well-being of complex organisms, as well as the possible causes and progression of disease. In addition to a fully labeled food source and appropriate mass spectrometry platform, an essential and enabling component of such large scale investigations is a robust data processing and analysis pipeline, which is capable of the reduction of large sets of liquid chromatography tandem MS raw data files into the desired protein turnover rate constants. The data processing pipeline described in this contribution is comprised of a suite of software modules required for the workflow that fulfills such requirements. This software platform includes established software tools such as a mass spectrometry database search engine together with several additional, novel data processing modules specifically developed for 15N metabolic labeling. These fulfill the following functions: (1) cross-extraction of 15N-containing ion intensities from raw data files at varying biosynthetic incorporation times, (2) computation of peptide 15N isotopic incorporation distributions, and (3) aggregation of relative isotope abundance curves for multiple peptides into single protein curves. In addition, processing parameter optimization and noise reduction procedures were found to be necessary in the processing modules in order to reduce propagation of errors in the long chain of the processing steps of the entire workflow.
Malignant Peripheral Nerve Sheath Tumour (MPNST): The Clinical Implications of Cellular Signalling Pathways

Malignant peripheral nerve sheath tumour (MPNST) is a rare malignancy accounting for 3-10% of all soft tissue sarcomas. Most MPNSTs arise in association with peripheral nerves or deep neurofibromas and may originate from neural crest cells, although the specific cell of origin is uncertain. Approximately half of MPNSTs occur in the setting of neurofibromatosis type 1 (NF1), an autosomal dominant disorder with an incidence of approximately one in 3500 persons; the remainder of MPNSTs develop sporadically. In addition to a variety of clinical manifestations, approximately 8-13% of NF1 patients develop MPNSTs, which are the leading cause of NF1-related mortality. Surgical resection is the mainstay of MPNST clinical management. However, because of invasive growth, propensity to metastasise, and limited sensitivity to chemotherapy and radiation, MPNST has a guarded to poor prognosis. Five-year survival rates of only 20-50% indicate an urgent need for improved therapeutic approaches. Recent work in this field has identified several altered intracellular signal transduction cascades and deregulated tyrosine kinase receptors, posing the possibility of personalised, targeted therapeutics. However, expanded knowledge of MPNST molecular pathobiology will be needed to meaningfully apply such approaches for the benefit of afflicted patients.
Engendering Change: Organizational Dynamics and Workplace Gender Desegregation, 1975-2005

We examine workplace-level sources of gender inequality to explore the link between organizational change and levels of workplace gender integration over time. To do so, we analyze the gender division of labor and key structural aspects of U.S. private-sector work establishments, using longitudinal data from the U.S. Equal Employment Opportunity Commission from 1975 to 2005. We find that women's presence in managerial positions is positively related to gender integration, as is both establishment size and growth. Additionally, the results show that trends toward gender integration are due to change within workplaces rather than new, relatively integrated workplaces entering the population overtime. Our results also provide compelling evidence that the effect of female managers varies dramatically across organizational contexts, with the strongest desegregating effects in larger and growing establishments. Finally, the effect of women's access to organizational power structures has sharply diminished overtime.
Food waste in campus dining operations: Inventory of pre-and post-consumer mass by food category, and estimation of embodied greenhouse gas emissions

There are many economic, social and environmental reasons to reduce the occurrence of food that is wasted. As communities consider options for managing their food waste streams, an understanding of the volume, composition and variability of these streams is needed to inform the decision-making process and potentially justify the capital investments needed for separation and treatment operations. This more detailed inventory also allows for the estimation of embodied resources in food that is wasted, demonstrated herein for greenhouse gas emissions (GHGs). Pre- and post-consumer food waste was collected from four all-you-care-to-eat Campus Dining Services (CDS) facilities at the University of Missouri, Columbia over 3 months in 2014. During the study period approximately 246.3 metric tons (t) of food reached the retail level at the four facilities. 232.4 t of this food was served and 13.9 t of it (10.1 t of edible and 3.8 t of inedible), was lost as pre-consumer waste. Over the same time period, an estimated 26.4 t of post-consumer food waste was generated at these facilities, 21.2 t of the waste edible and 5.3 t of it inedible. Overall, 5.6% of food reaching the retail level was lost at the pre-consumer stage and 10.7% was lost at the post-consumer stage. Out of the food categories examined, ‘fruits and vegetables’ constituted the largest source of food waste by weight, with grains as the second largest source of food waste by weight. GHGs embodied in edible food waste were calculated. Over the study period an estimated 11.1 t CO2e (100-yr) were embodied in the pre-consumer food waste and 56.1 t were embodied in post-consumer food waste for a total of 67.2 t. The ‘meat and protein’ category represents the largest embodiment of GHG emissions in both the pre- and post-consumer categories despite ranking fourth in total weight. Beef represents the largest contribution to post-consumer GHG emissions embodied in food waste with an estimated 34.1 t CO2e. This distinction between the greatest sources of food waste by weight and the greatest sources of GHG emissions is relevant when considering alternative management options for food waste.
Snarks from a Kászonyi perspective

This is a survey or exposition of a particular collection of results and open problems involving snarks - simple "cubic" (3-valent) graphs for which, for nontrivial reasons, the edges cannot be 3-colored. The results and problems here are rooted in a series of papers by Laszlo Kaszonyi that were published in the early 1970s. The problems posed in this survey paper can be tackled without too much specialized mathematical preparation, and in particular seem well suited for interested undergraduate mathematics students to pursue as independent research projects. This survey paper is intended to facilitate research on these problems.
The radiation effects on Galileo spacecraft systems at Jupiter

The Galileo spacecraft has been subjected to the harsh charged-particle environment around Jupiter since 1995. As the spacecraft has far exceeded the radiation dose for which it was designed, there have been a number of system failures attributable to radiation effects. This paper is a summary of those failures, the evidence for their connection to radiation related causes, and the associated fixes the Galileo flight team has implemented.
Privacy-Preserving Complex Query Evaluation over Semantically Secure Encrypted Data

In the last decade, several techniques have been proposed to evaluate different types of queries (e.g., range and aggregate queries) over encrypted data in a privacy-preserving manner. However, solutions supporting the privacy-preserving evaluation of complex queries over encrypted data have been developed only recently. Such recent techniques, however, are either insecure or not feasible for practical applications. In this paper, we propose a novel privacy-preserving query processing framework that supports complex queries over encrypted data in the cloud computing environment and addresses the shortcomings of previous approaches. At a high level, our framework utilizes both homomorphic encryption and garbled circuit techniques at different stages in query processing to achieve the best performance, while at the same time protecting the confidentiality of data, privacy of the user’s input query and hiding data access patterns. Also, as a part of query processing, we provide an efficient approach to systematically combine the predicate results (in encrypted form) of a query to derive the corresponding query evaluation result in a privacy-preserving manner. We theoretically and empirically analyze the performance of this approach and demonstrate its practical value over the current state-of-the-art techniques. Our proposed framework is very efficient from the user’s perspective, thus allowing a user to issue queries even using a resource constrained device (e.g., PDAs and cell phones).
The Body Politic as Spatial Metaphor

As part of a special issue on the geographies of citizenship, this paper considers the longstanding and popular metaphor of “the body politic” for a polity. The metaphor's comparative power is successful because it imports key geographic assumptions about how polities are best organized. It makes claims about society and space (premises about location, spatial organization), nature–society relations (how the two spheres do and do not connect) and cartographic representation (the human body is the optimal representation of spatial and natural relations in a polity). We describe three ways in which geographical imaginations are constructed: organic, mechanical, and posthuman bodies politic. Our goal is twofold: first is to consider the ways the deployment of the metaphor of the body is used in political theory to convey a normative conception of citizenship; second is to bridge the gap between political theory and geography by paying special attention to the ways the body is a space. The metaphor of the bod...
Approximate analytic continuation of the Rayleigh series (radar cross-section)

Pade approximants are used to continue approximately the Rayleigh series for the radar cross section (RCS) of the sphere beyond its radius of convergence. Numerical studies show that accurate results for the RCS can be obtained to ka approximately 2.2 if many series terms are available. Since this is rarely, if ever, the case, it is further demonstrated that even with only four nonzero terms available the technique is accurate to ka approximately 1.1. This provides an indication of the number of series coefficients that must be calculated to use the Rayleigh series in the lower part of the resonance regime. An additional point that is demonstrated is the ability of the technique to provide highly accurate estimates of the radius of convergence of the series. A useful byproduct is the generation of an approximation for the scattering of the sphere, valid for all real values of ka, which has a maximum error of less than 3%. >
Exercise as medicine for diabetes: prescribing appropriate activities and avoiding potential pitfalls: preface.

In this issue, I have the pleasure of further reinforcing for you the benefits of engaging in regular exercise, along with the more expansive realm of appropriate physical activities for people with diabetes. Although physical activity is a cornerstone in the management of diabetes, and the health benefits of exercise are widely touted as “medicine” for diabetes, many individuals with this chronic disease fail to become or remain regularly active (1). One barrier to being active is that exercise potentially has a large impact on the body’s metabolism, which, in some cases, can complicate the management of blood glucose levels. For example, a number of factors influence the exact contribution of various fuels to exercise metabolism, including (but not limited to) nutritional status, age, type of activity, physical fitness level, and glycemic balance. However, the most important influences on fuel utilization—and the resulting glycemic balance—are the intensity and duration of physical activity (2–10). This Diabetes Spectrum From Research to Practice section on exercise covers the latest trends, practices, suggestions, recommendations, and concerns regarding getting people with all types of diabetes more physically active to improve their health and, hopefully, their glycemic balance. The goal is to allow you to think more broadly about being active and how that can become a reality for each and every one of your patients, one way or another. Before you begin prescribing exercise to everyone, I need to add a word of caution related to advising sedentary individuals, in particular, to become more active. Before embarking on a new exercise program or even increasing their usual patterns of physical activity, people with diabetes are advised to undergo a detailed medical evaluation with appropriate screening for the presence of diabetes-related health complications that could potentially be worsened by exercise, including poor …
PackHelix: a tool for helix-sheet packing during protein structure prediction.

The three-dimensional structure of a protein is organized around the packing of its secondary structure elements. Predicting the topology and constructing the geometry of structural motifs involving α-helices and/or β-strands are therefore key steps for accurate prediction of protein structure. While many efforts have focused on how to pack helices and on how to sample exhaustively the topologies and geometries of multiple strands forming a β-sheet in a protein, there has been little progress on generating native-like packings of helices on sheets. We describe a method that can generate the packing of multiple helices on a given β-sheet for αβα sandwich type protein folds. This method mines the results of a statistical analysis of the conformations of αβ2 motifs in protein structures to provide input values for the geometric attributes of the packing of a helix on a sheet. It then proceeds with a geometric builder that generates multiple arrangements of the helices on the sheet of interest by sampling through these values and performing consistency checks that guarantee proper loop geometry between the helices and the strands, minimal number of collisions between the helices, and proper formation of a hydrophobic core. The method is implemented as a module of ProteinShop. Our results show that it produces structures that are within 4–6 A RMSD of the native one, regardless of the number of helices that need to be packed, though this number may increase if the protein has several helices between two consecutive strands in the sequence that pack on the sheet formed by these two strands. Proteins 2011; Published 2011 Wiley-Liss, Inc.
Predators, Prey Refuges, and the Spatial Scaling of Density-Dependent Prey Mortality

We tested the biological cause of density-dependent mortality in the bridled goby (Coryphopterus glaucofraenum), a small coral reef fish, and evaluated whether this knowledge allowed us to detect density dependence at different spatial scales in natural habitats. To identify the biological cause of density dependence, we manipulated both population density and the availability of shelter (crevices used as refuges from predators) in small plots of continuous reef. We detected strong density-dependent mortality in plots with few refuges, but mortality was density independent in plots with abundant refuges, indicating that limited shelter causes density dependence. Predator density was unrelated to the density of gobies and refuges, suggesting that predators displayed a type III functional response in patches with few refuges. In a second experiment, we manipulated goby density within replicate plots of three sizes (4, 16, and 64 m2) that varied naturally in the availability of refuges. If refuge availability was ignored, mortality appeared to be density independent at all scales. If, however, plots were grouped by refuge availability, mortality was density dependent in plots with few refuges, but low and density independent in plots with many refuges at all spatial scales. Understanding the mechanism of density dependence (refuge shortage) was thus required to measure the strength of density dependence in natural, spatially variable, habitat. We suggest that density dependence was detectable in plots of different sizes because the relationships between the densities of gobies, refuges, and goby predators were similar across the spatial scales we studied. Our work demonstrates that identifying the biological interactions that cause density dependence, and characterizing the spatial domains at which those interactions operate, will be important to accurately assess the effects of density dependence on population dynamics.
Evaluation of self monitoring of blood glucose in non-insulin-treated diabetic patients by randomized controlled trials: little bang for the buck.

Although self monitoring of blood glucose is accepted to be effective in lowering Hb A1c levels in insulin- treated diabetic patients, any benefit in non-insulin-treated patients remains controversial. Observational studies cannot answer this question because of either patient self selection (individuals with healthier life styles chose to perform more SMBG) or physician self selection (patients in poorer control are asked to perform SMBG). Only randomized controlled trials (RCTs) can provide the answer. Of the 14 published bona fide RCTs, nine show no benefit in lowering Hb A1c lev- els. In four of the five positive ones, the SMBG group received more intensive education and/or treatment than the control group. In the one in which patients in both groups were followed similarly, over 500 patients were required to produce a statistically significant difference of 0.2% favoring SMBG, the clinical significance of which is debatable. Thus, there is scant evidence that very expensive SMBG in non-insulin-treated patients is effective in lowering Hb A1c levels. This lack of benefit argues for redirecting these resources into areas of diabetes care where strong evidence exists for improving diabetes outcomes.
Examination of Gilded Bronze Artifacts Using Nondestructive Eddy Current Techniques

In the examination of gilded bronze objects, the analysis of the thickness of the gilding layer, the condition of the substrate and the gilding method is often difficult to manage without taking samples. Yet, the resulting information is vital to research on ancient metalworking and can answer questions of authenticity. The use of nondestructive eddy current techniques can overcome these sampling limitations. Eddy current methods are typically used in the automotive, power and aerospace industries for flaw inspection and alloy selection. In this method, the interaction of an electromagnetic field induced by a coil probe with the metal surface shifts the probe impedance which is measured and correlated to properties of the metal. Results are presented which show that eddy current testing can be used to characterize a gilding layer on a bronze substrate by variations in thickness or composition.
ANTAGONISM BETWEEN SEXUAL AND NATURAL SELECTION IN EXPERIMENTAL POPULATIONS OF SACCHAROMYCES CEREVISIAE

Trade-offs between life-history components are a central concept of evolution and ecology. Sexual and natural selection seem particularly apt to impose antagonistic selective pressures. When sex is not integrated into reproduction, as in Saccharomyces cerevisiae, natural selection can impair or even eliminate it. In this study, a genetic trade-off between the sexual and asexual phases of the yeast life cycle was suggested by sharp declines in the mating and sporulation abilities of unrelated genotypes that were propagated asexually in minimal growth medium and in mice. When sexual selection was applied to populations that had previously evolved asexually, sexual fitness increased but asexual fitness declined. No such negative correlation was observed when sexual selection was applied to an ancestral strain: sexual and asexual fitness both increased. Thus, evolutionary history affected the evolution of genetic correlations, as fitness increases in a population already well adapted to the environment were more likely to come at the expense of sexual functions.
Molecular Chaperones Activate the Drosophila Ecdysone Receptor, an RXR Heterodimer

The steroid hormone 20-hydroxyecdysone coordinates the stages of Drosophila development by activating a nuclear receptor heterodimer consisting of the ecdysone receptor, EcR, and the Drosophila RXR receptor, USP. We show that EcR/USP DNA binding activity requires activation by a chaperone heterocomplex like that required for activation of the vertebrate steroid receptors, but not previously shown to be required for activation of RXR heterodimers. Six proteins normally present in the chaperone complex were individually purified and shown to be sufficient for this activation. We also show that two of the six (Hsp90 and Hsc70) are required in vivo for ecdysone receptor activity, and that EcR is the primary target of the chaperone complex.
Private finance for public goods: social impact bonds

Social impact bonds (SIBs) attract private investment to social programs by paying a market rate of return if predefined outcome targets are met. SIBs monetize benefits of social interventions and tie pay to performance, limiting governmental control once the contract is designed. Despite policy enthusiasm across the globe, SIBs have failed to attract private market investors without substantial additional guarantees. SIBs raise questions about government’s ability to ensure broader public values. Using literature on contracting, performance management, and public private partnerships, this exploratory analysis focuses on institutional design, transaction costs, and performance measurement, outlining the opportunities and concerns SIBs present.
Restoration of visual function following optic nerve regeneration in bluegill (Lepomis macrochirus) x pumpkinseed (Lepomis gibbosus) hybrid sunfish

Simple ~dorsal light reflex! and complex ~predator-prey interactions! visually mediated behaviors were used concurrently with morphological examination to assess restoration of visual function following optic nerve crush in bluegill ~Lepomis macrochirus! pumpkinseed ~Lepomis gibbosus! hybrid sunfish. Regenerating optic nerve axons projected into the stratum opticum-stratum fibrosum et griseum superficiale by week 2, the stratum griseum centrale by week 4, and stratum album centrale by week 6. Initial projections into the laminae were diffuse and less stratified compared to controls. By week 12, the projection pattern of regenerating nerve fibers closely resembled the innervation of normal tecta. Visual improvements were correlated with increasing projections into the tectum. The dorsal light reflex improved from a 458 vertical deviation following nerve crush to 4.58 by week 16. Initial predator-prey interactions were exclusively mediated by the control eye. As regeneration progressed, there was a gradual expansion of the visual field. The reaction distance and attack angles within the visual field of the experimental eye were initially less than controls, however, these differences disappeared by week 10. Improvements in visual function were closely correlated with an increase of regenerating ganglion cell axons into the optic tectum indicating sufficient synaptogenesis to mediate both simple and complex visual behavior.
Trajectory Generation for Effective Sensing

Unmanned aerial vehicles (UAVs) stand to play a significant role in envisioned sensing and information gathering missions. The scope of these mission scenarios is expanding to include those missions for which the sensor and carrier vehicle will be in close proximity to the surrounding environment. Consequently, several unique problems are introduced. First, coupling between the motion of the vehicle and the direction of sensor pointing has a significant effect on gathered data. Second, view characteristics of sensed objects will vary appreciably over the sensor field-of-view. Such variations affect data quality amongst these sensed objects. Third, close proximity to obstacles requires a trajectory planning method that adequately accounts for vehicle dynamics to insure safe navigation. This paper develops a trajectory planning strategy to effectively sense an environment at close range. A generalized measure of sensing effectiveness is formulated and utilized as a performance metric. A randomized motion planning scheme is then utilized to generate dynamically-feasible trajectories that maximize sensing effectiveness within such environments.
Can World System Theory predict news flow on twitter? The case of government-sponsored broadcasting

ABSTRACTSocial media platforms provide world governments with the opportunity to distribute news content from their broadcast channels directly to foreign publics [Wallerstein, I. (1974). The modern world system. New York: Academic Press] World System Theory, which has successfully explained and predicted the structure of international news flow, is now being challenged. Specifically, these social platforms undermined assumptions regarding the one-way flow of information toward audiences and the exclusive institutional nature of the players in the international system. This study examines the unique case of government-sponsored news media and its international news flow. It finds that while the structure of the international news flow on Twitter exhibits a hierarchical core–periphery structure, non-institutional actors (e.g. bloggers) conformed less than institutional players (e.g. governments and news media) to that structure. This study also found that non-institutional actors assumed the role of bridgi...
An Ira Strategy for the Unemployed

A person who becomes unemployed for an extended period often experiences a significant decrease in his or her marginal tax rate (MTR) because of lower levels of taxable income. In this article, we demonstrate how the recently unemployed can use to their advantage a traditional IRA that permits a tax deduction for contributions of up to $5,000 in 2008, or other qualified retirement plans. Qualified retirement plans are generally viewed as a long-term tax planning tool; however, they can also be used as a short-term tool to shift income between tax years. Although several types of qualified retirement plans can be used in the strategy, an IRA is the best vehicle because it permits contributions any time before and including the April 15 filing deadline of the following tax year.
The Treatment of Renal Stones by Lithotripsy: Indications, Limits, Results, Complications

Extracorporeal shockwave lithotripsy (ESWL) was introduced clinically in 1980, eight years after renal calculi were successfully destroyed in vitro using shock waves (1, 2). To date, more than 500,000 patients have been treated worldwide and ESWL, either alone or in conjunction with percutaneous nephrolithotomy (PCNL), has replaced open surgery as the ideal mode of treatment for the vast majority of symptomatic renal calculi. Herein, we have reviewed the treatment results, the complications and the limits of ESWL therapy with the Dornier HM3 lithotriptor. This task is complicated by the lack of uniformity between different published series and the absence of substratification of patient populations with regards to stone site, size and multiplicity. We have also briefly outlined the characteristics of the various “second generation lithotriptors” which are available worldwide.