cssi/SciSciGPT-SciSciNet huggingface dataset:
Genetics of resistance to the African trypanosomes. IV. Resistance of radiation chimeras to Trypanosoma rhodesiense infection.

The cellular bases of resistance to the African trypanosomes were examined in inbred mice. As part of these studies, reciprocal bone marrow cell transplants were performed between H-2 compatible mice which differ in relative resistance to Trypanosoma brucei rhodesiense infection. Survival times, parasitemias and IgM antibody responses to the surface antigen of the infecting variant type were measured in these semiallogeneic bone marrow chimeras. Relatively resistant C57BL/10 mice, intermediate A.By mice, and least resistant C3H.SW mice that were reconstituted after lethal irradiation with syngeneic bone marrow cells displayed resistance and immunity characteristic of the homologous donor strain. When C57BL/10 mice were reconstituted with C3H.SW mouse bone marrow cells they retained the ability to produce antibodies to trypanosome surface antigen but the antibody titers were significantly reduced. Control of parasitemia and mean survival time were reduced in these chimeras, but differed significantly from C3H.SW mice. A.By mice that received cells from C57BL/10 donors exhibited antibody responses and survival times similar to the C57BL/10 mice. Survival times of A.By mice given syngeneic cells or C3H.SW cells were the same, but the antibody responses of A.By mice given C3H.SW cells were lower than those of A.By mice given syngeneic cells. C3H.SW mice reconstituted with C57BL/10 bone marrow cells were capable of making antibodies and controlling parasitemia, in marked contrast to the absence of such responses in C3H.SW mice reconstituted with syngeneic cells. Survival times, however, were indistinguishable from those of C3H.SW mice given syngeneic cells. Thus, resistance to T. b. rhodesiense was shown for the first time to depend on donor bone marrow derived cells as well as upon radiation-resistant cells/factors associated with host genetic background. Also, parasite-specific IgM antibody responses seem to be regulated by a mechanism which does not depend on bone marrow derived cells alone, and the presence of such immune responses is not linked to survival time.
Electronic Structure of Solids

Metals and semiconductors have crystal structures with a well-defined translational symmetry. Most important among the crystal structures are the simple cubic, body-centered cubic and face-centered cubic structures, the diamond structure, and the hexagonal close-packed structure. The structure of the crystal of which a substance is composed has an important effect upon the properties of the wave functions of electrons moving through the crystal. The free-electron wave functions are periodic with respect to the crystal lattice if the wave vector ‘k’ belongs to the reciprocal lattice. The reciprocal lattice of the simple cubic lattice is itself a cubic lattice, the reciprocal lattice of the body-centered cubic lattice is a face-centered cubic lattice, and vice-versa. The unit cell of the reciprocal lattice is called the Brillouin zone. Bloch's theorem shows that the translational symmetry of the lattice imposes a strong condition upon the form of the wave function. According to Bloch's theorem, the translational symmetry of the lattice implies that each wave function, which is a solution of the Schrodinger equation, has an associated wave vector ‘k’. Each electron having a wave vector ‘k’ interacts with an electron with the mirror image of k across the boundary of the Brillouin zone.
A concept of semiconductor optical routing device utilizing minority carrier drift

A novel concept of semiconductor optical routing device for short distance optical communication system, such as a board to board communication or grid computing. A semiconductor optical routing devices utilizing minority-carrier-drift was discussed. The feasibility of a multi-channel dynamic semiconductor optical routing devices operating for the first time. P-type modulation doped heterostructures were designed for SORDs. At room temperature PL emission from the Al/sub 0.9/Ga/sub 0.1/As barrier layers.
Matrix Isolation Infrared Spectroscopy

The experimental methods for performing cryogenic matrix-isolation infrared spectroscopic measurements on reactive species are described. A number of different techniques for preparing reactive species for matrix trapping are presented. Some representative infrared (IR) spectra and 30 references are given. Keywords: matrix-isolation; IR spectroscopy; reactive species; cryogenic spectroscopy; deposition methods
Molecular Analysis of Pediatric Oligodendrogliomas Highlights Genetic Differences with Adult Counterparts and Other Pediatric Gliomas.

Oligodendroglioma represents a distinctive neoplasm in adults but similar neoplasms occur rarely in children. We studied 20 cases of pediatric oligodendroglioma by SNP array (median age 9 years, range 1–19; 15 grade II and 5 grade III). Cytogenetic abnormalities were present in 8 (53%) grade II and all five anaplastic oligodendrogliomas. Most changes were in the form of deletion and copy neutral loss of heterozygosity (LOH). The most common abnormality was 1p deletion (n = 5). Whole arm 1p19q co-deletion was present in three cases from adolescent patients and 9p loss in 3, including one low-grade oligodendroglioma with CDKN2A homozygous deletion. Common losses were largely limited to the anaplastic subset (n = 5) and included 3q29 (n = 3), 11p (n = 3), 17q (n = 3), 4q (n = 2), 6p (n = 2), 13q (n = 2), 14q (n = 2), 17p (n = 2) and whole Ch 18 loss (n = 2). Gains were non-recurrent except for whole Ch 7 (n = 2) and gain on 12q (n = 2) including the MDM2 locus. Possible germ line LOH (or uniparental disomy) was present in seven cases (35%), with one focal abnormality (22q13.1-13.2) in two. BRAF-KIAA1549 fusions and BRAF p.V600E mutations were absent (n = 13 and 8). In summary, cytogenetic alterations in pediatric oligodendrogliomas are characterized mostly by genomic losses, particularly in anaplastic tumors.
A knowledge-based approach to organizing retrieved documents

When people use computer-based tools to find answers to general questions, they often are faced with a daunting list of search results or "hits" returned by the search engine. Many search tools address this problem by helping users to make their searches more specific. However, when dozens or hundreds of documents are relevant to their question, users need tools that help them to explore and to understand their search results, rather than ones that eliminate a portion of those results. In this paper, we present DynaCat, a tool that dynamically categorizes search results into a hierarchical organization by using knowledge of important kinds of queries and a model of the domain terminology. Results from our evaluation show that DynaCat helps users find answers to those important types of questions more quickly and easily than when they use a relevance-ranking system or a clustering system.
Insulin-glucagon substrate interrelationships in the neonatal sheep.

Abstract The pancreatic alpha and beta cell responses to glucose and deoxyglucose infusion were studied in nine healthy newborn lambs at 24 to 36 hours of age. Steady-state glucose infusion resulted in a significant, though obtunded, increase in plasma insulin concentrations within 45 minutes; glucose/insulin ratios were higher than fetal values observed in similar studies (5.6 vs. 0.88, p
A closed conformation for the Pol lambda catalytic cycle.

Pol λ is a family X member believed to fill short gaps during DNA repair. Here we report crystal structures of Pol λ representing three steps in filling a single-nucleotide gap. These structures indicate that, unlike other DNA polymerases, Pol λ does not undergo large subdomain movements during catalysis, and they provide a clear characterization of the geometry and stereochemistry of the in-line nucleotidyl transfer reaction.
Utilizing low forward voltage drop power semiconductors to minimize heat sinking requirements in multichip module DC solid state relays and static switching applications

This paper provides a concise overview of the impact of new ultra low RDS(on) MOSFET technology, low V/sub f/ Schottky technology, and low V/sub ce(on)/ bipolar technology devices as applied to control of low voltage DC power. Device selection criteria and circuit topologies are provided along with empirical and FEA modeling data on heat sinking and power dissipation.
Radioiodinated I -substituted-4-phenylpiperazines as potential brain imaging agents

Abstract A series of four 125 I-labeled 1-substituted-4-phenylpiperazines were prepared and evaluated in rats as potential brain imaging agents. The compounds were labeled using [125I]iodide/chloramine-T or iodine monochloride and isolated in 48–60% radiochemical yields. The tissue distribution studies indicated that a butyrophenone derivative demonstrated the best overall brain-imaging properties. Compared with the compounds having other 1-substituents this agent had a more prolonged retention of activity in the brain and higher brain-to-blood ratios over the 4-h period studied. The in vivo behavior of this agent is comparable to that of radioiodinated N-isopropyl-p-iodoamphetamine, and, because it can be labeled directly via electrophilic methods, it has substantial potential for use in brain imaging with single photon emission computed tomography.
The nature of glassforming liquids, the origin of superionics and ‘tight’ vs. ‘loose’ glassy conductors

Abstract As background for the phenomenology of fast ion conducting glassy materials, we review key features of the ionic liquid states from which they form. Current issues concerning the behavior of molecular liquids, including the relation of crossovers in dynamic behavior during cooling to the onset of clustering and the splitting-off of secondary relaxations, are considered. The decoupling of conducting modes from viscous modes involved in the generation of ion conducting glasses on cooling below Tg, is apparently quite distinct from the clustering involved in the α-β bifurcation, and tends to be most pronounced in the ‘stronger’ liquids. Using ion dynamics simulations, we trace its origin to the existence of high anharmonicity in the vibrational modes of the mobile species. This is most probable when the mobile ion is small but uncompetitive in the determination of local and intermediate range glass structure. Glasses with such species should share a number of characteristics. The classification of ‘loose’ (vs. ‘tight’) ionic conductors is introduced to separate the behavior of such systems from that of ‘tight’ ionic conductors which should be insulators below Tg. The absence of conductivity dispersion should be a feature of the latter when the liquids are ‘strong’ as opposed to ‘fragile’. The possible relation of ‘looseness’ to the presence or otherwise of the ‘universal’ background loss (e″~f) is discussed.
The Bouchayers of Grenoble and French Industrial Enterprise, 1850–1970 . By Robert J. Smith. Baltimore: The Johns Hopkins University Press, 2001. Pp. xix, 247. $42.50.

Ever since David Landes's seminal work on the French family firm and the interplay of culture and economics, French business history has wrestled with the question of French particularism and the role of family enterprise in determining business outcomes. For well over a quarter of a century, historians have challenged or qualified Landes's arguments, first by pointing to successful family enterprises in France or elsewhere, second by reassessing French economic performance in modern times, and third by identifying other factors to explain slower growth in macro or micro terms. Robert J. Smith's thought-provoking study of Bouchayer et Viallet, a medium-sized French firm that rose and fell on family leadership and culture, squarely confronts, once again, the issue of family influence on business success and failure. Combining access to family papers with an astute appraisal of personality and context, Smith has produced a first-rate inquiry into the dynamics of family business firms. Mindful of the fact that family firms still account for a predominant part of GNP, but that few family firms continue as such for more than several generations, Smith asks how family control and values contributed to the success of Bouchayer et Viallet yet also braked growth at a middling level and ultimately undermined the continuity of the company. Intended as a case study in the trajectory of family enterprise, Smith weaves together business, family, and cultural history in exemplary ways that will benefit practitioners of all three fields and that demonstrate the value of the first approach for studying and writing the second and the third.
Impulse absorption by tapered horizontal alignments of elastic spheres.

We present an analytical and numerical study of the problem of mechanical impulse propagation through a horizontal alignment of progressively shrinking (tapered) elastic spheres that are placed between two rigid end walls. The studies are confined to cases where initial loading between the spheres is zero (i.e., in the ``sonic vacuum'' region). The spheres are assumed to interact via the Hertz potential. Force and energy as a function of time for selected grains that comprise the solitary wave are provided and shed light on the system's behavior. Propagation of energy is analytically studied in the hard-sphere approximation and phase diagrams plotting normalized kinetic energy of the smallest grain at the tapered end are developed for various chain lengths and tapering factors. These details are then compared to kinetic energy phase diagrams obtained via extensive dynamical simulations. Our figures indicate that the ratios of the kinetic energies of the smallest to largest grains possess a Gaussian dependence on tapering and an exponential decay when the number of grains increases. The conclusions are independent of system size, thus being applicable to tapered alignments of micron-sized spheres as well as those that are macroscopic and more easily realizable in the laboratory. Results demonstrate the capabililty of these chains to thermalize propagating impulses and thereby act as potential shock absorbing devices.
In silico studies of polyaromatic hydrocarbon inhibitors of cytochrome P450 enzymes 1A1, 1A2, 2A6, and 2B1.

A computational study was undertaken to understand the nature of binding and the structural features that play a significant role in the binding of arylacetylene molecules to cytochrome P450 enzymes 1A1, 1A2, 2A6, and 2B1. Nine polycyclic arylacetylenes determined to be mechanism-based P450 enzyme inhibitors were studied. The lack of polar substituents in these compounds causes them to be incapable of hydrogen bonding to the polar protein residues. The four P450 enzymes of interest all have phenylalanine residues in the binding pocket for potential π−π interactions with the aromatic rings of the inhibitors. The inhibition potency of these arylacetylenes toward P450s 1A1 and 2B1 showed a dependence on the proximity of the inhibitor’s triple bond to the prosthetic heme Fe of the enzyme. In P450 enzyme 1A2, the inhibitor’s potency showed more dependence on the π−π interactions of the inhibitor’s ring systems with the phenylalanine residues of the protein, with the proximity of the inhibitor triple bond to th...
Fidelity of bacterial source tracking: Escherichia coli vs Enterococcus spp and minimizing assignment of isolates from nonlibrary sources

Aims: The goal of the study was to improve the fidelity of library-dependent bacterial source tracking efforts in determining sources of faecal pollution. The first objective was to compare the fidelity of source assignments using Escherichia coli vs Enterococcus spp. The second objective was to determine the efficacy of using thresholds during source assignments to reduce the rate of misassignments when nonlibrary isolates (i.e. isolates from animals not used in building the identification library) are present. Methods and Results: E. coli and Enterococcus isolates from 784 human, cow, deer, dog, chicken, and gull faecal samples were fingerprinted using BOX-PCR. Jack-knife analysis of the fingerprints showed that the overall rate of correct assignment (ORCA) of 867 E. coli isolates was 67% compared with 82% for 1020 Enterococcus isolates. In a separate blind test using similarity value and quality factor thresholds, the ORCA of 130 E. coli and 131 Enterococcus isolates were 70% and 98%, respectively. The use of these thresholds reduced misassignment of 262 nonlibrary enterococcal isolates from horses, goats, pigs, bats, squirrels, ducks, geese, and migratory song birds. Misassignment was reduced from 100% when thresholds were not used, to 47% using similarity threshold alone, and to 12% when both thresholds were used. Conclusions: The use of enterococci provides higher rates of correct source assignment compared with E. coli. The use of similarity thresholds to decide whether to accept source assignments made by computer programmes reduces the rate of misassignment of nonlibrary isolates. Significance and Impact of the Study: Although both E. coli and Enterococcus spp. are still used in microbial source tracking, the use of enterococci should be preferred over the use of E. coli in DNA fingerprint-based efforts. In addition, because environmental isolates are not limited to those from animals used to build source tracking libraries, similarity thresholds should be used during source assignments to reduce the rate of misassignments.
Neuronal Production of Fibronectin in the Cerebral Cortex during Migration and Layer Formation Is Unique to Specific Cortical Domains

The distribution of fibronectin (FN) changes rapidly during early development of the cerebral cortex, but its cellular source is not known. Within situhybridization we find two spatially and temporally distinct periods of FN mRNA expression in the embryonic and early postnatal cortex of the mouse. Before and during formation of the preplate by the first postmitotic neurons, FN mRNA levels are high throughout the telencephalic vesicle, deep in the neuroepithelial proliferative zone that contains dividing cells and the cell bodies of radial glia; expression in the cortical proliferative zone is limited to the period of neurogenesis. Just after the cortical plate is formed within the preplate, FN mRNA is expressed in the intermediate zone, which contains migrating neurons, and in the cortical plate, where neurons migrate past their predecessors to form layers. Brefeldin A treatment of an organotypic slice preparation demonstrates FN production in the intermediate zone and cortical plate, in locations that correspond exactly to the distribution of FN mRNA byin situhybridization. FN-producing cells immunolabel with neuron-specific markers; in the intermediate zone and lower cortical plate they have morphological features characteristic of migrating neurons and are closely apposed to radial glia. FN mRNA expression and protein production continue in neurons of the cortical plate through the period of layer formation and then are down-regulated. Examination of dissociated cortical cells by laser confocal microscopy confirms that FN accumulation after brefeldin A treatment is intracellular in neurons as well as in glia. Neuroepithelial expression of FN mRNA takes place throughout the telencephalon; FN produced by neurons is restricted to cells migrating toward and into specific cortical domains that include neocortex, insular and perirhinal cortex, and subiculum. Thus FN may be involved initially in supporting the cell division and fate determination that takes place in the neuroepithelium; later production by migrating neurons may play a role in the selection of radial glial pathways that lead to specific cortical regions, and in interactions between neurons as they form cortical layers within these regions.
The local interstellar medium as observed from Lyman

Abstract The characteristics of the proposed LYMAN satellite are discussed briefly, and numerous problems associated with the Local Interstellar Medium are identified to which LYMAN can make significant contributions.
The Role of Sex Differences in Autophagy in the Heart During Coxsackievirus B3-Induced Myocarditis

Under normal conditions, autophagy maintains cardiomyocyte health and integrity through turnover of organelles. During stress, oxygen and nutrient deprivation, or microbial infection, autophagy prolongs cardiomyocyte survival. Sex differences in induction of cell death may to some extent explain the disparity between the sexes in many human diseases. However, sex differences in gene expression, which regulate cell death and autophagy, were so far not taken in consideration to explain the sex bias of viral myocarditis. Coxsackievirus B3 (CVB3)-induced myocarditis is a sex-biased disease, with females being substantially less susceptible than males and sex hormones largely determine this bias. CVB3 was shown to induce and subvert the autophagosome for its optimal viral RNA replication. Gene expression analysis on mouse and human, healthy and CVB3-infected, cardiac samples of both sexes, suggests sex differences in autophagy-related gene expression. This review discusses the aspects of sex bias in autophagy induction in cardiomyocytes.
The introduction of proof in secondary geometry textbooks

Abstract Explicit reasoning-and-proving opportunities in the United States are often relegated to a single secondary geometry course. This study analyzed the reasoning-and-proving opportunities in six U.S. geometry textbooks, giving particular attention to the chapter that introduced proof. Analysis focused on the types of reasoning-and-proving activities expected of students and the type of mathematical statement around which the reasoning-and-proving took place, be it general or particular. Results include the fact that reasoning-and-proving opportunities in student exercises were predominantly of the particular type, whereas textbook exposition most commonly had general statements. Within the chapters introducing proof, opportunities for students to develop proofs were less common than exercises involving conjectures and statements or exercises about the reasoning-and-proving process. Opportunities to reflect on the reasoning-and-proving process were prevalent in the introduction chapters, though rare in the remainder of the books.
Oxidation of reduced pyridine nucleotides by plasma membranes of soybean hypocotyl

Highly purified plasma membranes isolated from soybean hypocotyls by free-flow electrophoresis or by a two-phase polymer separation system oxidize reduced pyridine nucleotides, NADH or NADPH, at rates of 2-5 nanomoles/mg protein/min. These rates are not influenced by mitochondrial inhibitors or by inhibitors of the alternate respiratory pathway. The NADH oxidase has a Km of 200 microM NADH. The enzyme activity is stimulated by Ca2+ and Mg2+ ions. The function of this enzyme is unknown at present, but it may represent a redox-controlled proton pump linked to acidification.
Prevalence of risk factors to coronary heart disease in an Arab-American population in Southeast Michigan

Although significant advances have been made in the area of cardiovascular disease, few studies have targeted ethnic groups. There is a large and growing Arab-American (AA) population living in Sou...
Genetic diversity of herbicide-resistant and -susceptible Avena fatua populations in North Dakota and Minnesota

Summary Genetic diversity within and among 20 herbicide-resistant (HR) and 16 herbicide-susceptible (HS) Avena fatua multi-field populations was determined using 82 polymorphic loci resulting from two intersimple sequence repeat (ISSR) primers and one long-primer random amplified polymorphic DNA (LP-RAPD) primer. Collections from the Red River Valley of North Dakota and Minnesota, sampled in 1964 and 2000, represented A. fatua populations before and after intensive exposure to herbicides. A 1995 collection from south-west North Dakota represented A. fatua exposed to low herbicide selection. Despite differences in years of herbicide exposure among collections, both HR and HS populations from every collection maintained nearly similar levels of ISSR and RAPD diversity. Genetic differentiation among populations (GST) varied from 11% to 13% among HR populations and from 9% to 16% among HS populations, indicating that 84–91% of total variation remained within HS or within HR populations. Minimal difference in gene diversity between HR and HS is consistent with multiple origins of resistance, where HR A. fatua most likely evolved from diverse founding individuals.
KIBITZ: the design of a bridge-bidding program utilizing simulated human judgement

The design of a program utilizing simulated human judgement to bid bridge hands is presented. The program is a new application of a technique developed by Peter G. Ossorio and H. Joel Jeffrey, which transforms a body of expert judgements into orthogonal matrices referred to as "judgement spaces". The process by which the bids are produced is compared to the operation of a finite state machine: the states reflect the condition of the auction, the bids themselves move the machine from one state to the other, and the characteristics of the bridge hands -- as perceived by the experts -- control the state-to-state transitions. A description of the mechanics of bridge bidding is appended.
Performance Measures Prevalent and Important but Methodologically Challenging

Performance measures are important. They shape the future and indirectly determine the quality of human life. However, performance measures often assess something other than what researchers assume...
Border food and food on the border: meaning and practice in Mexican haute cuisine

Restaurants and their attendant practices are high-profile sites at which regional and national cuisines are experienced, experimented with, and negotiated. In particular, they are important settings for the consumption and production of national identity—a crucial space through which to understand the coalescing of the material and representational. This article focuses specifically on the production side of the pairing through an examination of restaurants that are part of a prominent culinary movement (alta cocina mexicana) in the Mexican border town of Tijuana. The central argument of the paper is that Tijuana's culinary scene is indicative of the reassertion of boundaries between Mexico and the USA through the intentional rejection of northern stereotypes of Mexican food. The emphasis on traditional Mexican cuisine, rather than an internationally hybrid cosmopolitan approach, suggests that chefs are adhering to a set of rules that reflect Mexicanness. Restaurants propagating alta cocina mexicana work...
Wrist Postures While Typing on a Standard and Split Keyboard

Fifty experienced typists participated in a laboratory based repeated measures study with two factors: keyboard height (three) and keyboard configuration (three). The work surface heights tested we...
Candidate Gene Analysis of the Surfactant Protein D Gene in Pediatric Diffuse Lung Disease

Mutations in surfactant-associated genes cause childhood diffuse lung disease. Mice lacking surfactant protein D develop lung disease with age. However, we identified no novel surfactant protein D gene ( SFTPD ) coding or splice region variants in 73 unrelated children with diffuse lung disease from a cohort enriched for genetic surfactant dysfunction.
Treatment of stereotyped toe-walking with overcorrection and physical therapy

Abstract The present study reports on the successful integration of a behavior therapy technique (positive practice overcorrection) within a traditional physical therapy program for reducing stereotyped toe-walking in a nine-year-old moderately mentally retarded boy with bilateral heel cord tightening. The integration of therapies was effected following the unsuccessful long-term use of therapeutic exercise program alone. In addition, a verbal warning procedure was used to maintain the near-zero rates of stereotyped toe-walking upon the conclusion of active treatment. Follow-up data for six weeks were reported.
A framework for Internet-based surface texture analysis and information system

With the emergence of a global market and the recent trend of outsourcing, it is necessary for companies to have tools for remote access of data and an ability to analyze and troubleshoot manufacturing processes remotely. This need is addressed by developing an Internet-based surface texture analysis and information system, and a peer-to-peer data-sharing tool. These systems will help companies to diagnose problems related to surface texture in manufacturing process remotely. The development of the system has provided engineers from industry and academia a common framework for sharing, analyzing and storing surface texture data, analysis results, documents and reports. The system also provides a platform for quick deployment of solutions developed anywhere in the world. This paper presents the design, development and applications of a framework for surface texture analysis and information system.
TIME VARIABILITY IN MARKET RISK AVERSION

We adopt realized covariances to estimate the coefficient of risk aversion across portfolios and through time. Our approach yields second moments that are free from measurement error and not influenced by a specified model for expected returns. Supporting the permanent income hypothesis, we find risk aversion responds to consumption-smoothing behavior. As income increases, or as the consumption-to-income ratio falls, relative risk aversion decreases. We also document variation in risk aversion across portfolios: risk aversion is highest for small and value portfolios.
Pro-Active Fitness for Service of 19 Meter Diameter NGL Surge Sphere

To minimize costly down time, pro-active in lieu of reactive FFS assessments offer distinct advantages since the acceptable/unacceptable defect geometries and limitations are determined prior to the actual inspection. General Corrosion, LTAs and pitting were detected in the lower accessible sections of this 2″ average thickness sphere designed to ASME Section VIII, Division 2. API-510 and API-579 Levels 1, 2 and 3 were utilized to evaluate the documented defects in a comparison study. The defect geometries were then extrapolated to unacceptable levels to be used as a go/no-go reference tool for the remainder of the sphere and future inspections. Excel spread sheet numerical calculations and FEA non-linear analyses are employed. A significant increase in service life and defect tolerance over API-510 is realized.Copyright © 2002 by ASME
On the multiple melting behavior of bisphenol-A polycarbonate

Abstract Differential scanning calorimetry studies of the heating rate dependence of the multiple melting behavior of semicrystalline bisphenol A-polycarbonate (BAPC) are presented for different molar masses. In all cases, heating traces exhibit, in addition to the high temperature endothermic transition, a low endotherm located slightly above the crystallization temperature. After proper correction of the thermal lag effects, the high endotherm melting temperatures of the higher molar mass BAPC-19K and BAPC-28K samples are found to be independent of heating rate whether or not partial melting was carried out prior to recording the heating trace. These results demonstrate that the double melting behavior observed for high molar mass BAPC cannot be explained by a melting–recrystallization–remelting mechanism. In contrast, heating traces of the lower molar mass BAPC-4K sample exhibits two melting transitions within the high temperature endothermic region, which change both in magnitude and location with scanning rate, suggesting that melting–recrystallization–remelting can occur when chain mobility is sufficient to allow recrystallization. However, in all cases, the low and high endothermic regions are associated with the melting of two distinct populations of crystals, which have different thermal stability and are both present in the as-crystallized material. Crystallization studies after partial melting indicates that the low endotherm is associated with secondary crystals. The observed linear dependence of the melting temperature of secondary crystals with the square root of heating rate is consistent with superheating of secondary crystals. The origin of the superheating behavior is discussed in the context of conformational constraints in the residual amorphous fraction and the effect of crystallization time and molar mass on the low endotherm location.
Activation of FP Prostanoid Receptor Isoforms Leads to Rho-mediated Changes in Cell Morphology and in the Cell Cytoskeleton *

Prostaglandin F2α(PGF2α) exerts its biological effects by binding to and activating FP prostanoid receptors. These receptors, which include two isoforms, the FPA and FPB, have been cloned from a number of species and are members of the superfamily of G-protein-coupled receptors. Previous studies have shown that the activation of FP receptors leads to phosphatidylinositol hydrolysis, intracellular calcium release, and activation of protein kinase C. Here, we demonstrate that PGF2α treatment of 293-EBNA (Epstein-Barr nuclear antigen) cells that have been stably transfected with either the FPA or FPB receptor isoforms leads to changes in cell morphology and in the cell cytoskeleton. Specifically, cells treated with PGF2α show retraction of filopodia and become rounded, and actin stress fibers are formed. Pretreatment of the cells with bisindolylmaleimide I, a protein kinase C inhibitor, has no effect on the PGF2α-induced changes in cell morphology, although it does block the effects of phorbol myristate acetate on cell morphology. On the other hand, the PGF2α-induced changes in cell morphology and formation of actin stress fibers can be blocked by pretreatment of the cells with C3 exoenzyme, a specific inhibitor of the small G-protein, Rho. Consistent with FP receptor induced formation of actin stress fibers and focal adhesions, FPA receptor activation also leads to rapid (within two minutes) tyrosine phosphorylation of p125 focal adhesion kinase (FAK) which can be blocked by pretreating the cells with C3 exoenzyme. Taken together, these results suggest that the FP receptor isoforms are coupled to at least two second messenger pathways, one pathway associated with protein kinase C activation, and the other with activation of Rho.
Do Heparin-Like Receptors Play a Role in the Attachment of Respiratory Syncitial Virus to Epithelial Cells?

Do Heparin-Like Receptors Play a Role in the Attachment of Respiratory Syncitial Virus to Epithelial Cells?
A simple method for rapid and precise estimation of the protamine dose required for clinical heparin reversal

A simple, colorimetric protamine titration method was developed for rapid and precise estimation of the protamine dose required for clinical heparin reversal. The method employs azure A dye as the titration indicator, and has replaced the time consuming clotting assay in the conventional protamine titration method with a rapid colorimetric assay. It offers the same accuracy in estimating the protamine dose as that of the conventional titration method, but allows the processing time to be shortened to within 5 min. In a similar manner, the colorimetric assay can also be employed with a heparin titration procedure to quickly assess the heparin dose required for protamine reversal. This would allow physicians to exercise a quick and accurate heparin back-titration to patients who are overdosed with protamine.
School's out: what are urban children doing? The Summer Activity Study of Somerville Youth (SASSY)

Research indicates that in the United States, children experience healthier BMI and fitness levels during school vs. summer, but research is limited. The primary goal of this pilot study was to assess where children spend their time during the months that school is not in session and to learn about the different types of activities they engage in within different care settings. A secondary goal of this pilot study was to learn what children eat during the summer months. A nine-week summer study of 57 parents of second and third grade students was conducted in an economically, racial/ethnically and linguistically diverse US urban city. Weekly telephone interviews queried time and activities spent on/in 1) the main caregiver's care 2) someone else's care 3) vacation 4) and camp. Activities were categorised as sedentary, light, moderate, or vigorous (0-3 scale). For each child, a mean activity level was calculated and weighted for proportion of time spent in each care situation, yielding a weighted activity index. On the last phone call, parents answered questions about their child's diet over the summer. Two post-study focus groups were conducted to help interpret findings from the weekly activity interviews. The mean activity index was 1.05 ± 0.32 and differed between gender (p = 0.07), education (p = 0.08) and primary language spoken in the household (p = 0.01). Children who spent a greater percentage of time in parent care had on average a lower activity index (β = -0.004, p = 0.01) while children who spent a greater percentage of time in camp had a higher activity index (β = 0.004, p = 0.03). When stratified into type of camp, percentage of time spent in active camp was also positively associated with mean activity index (β = 0.005, p =< 0.001). With regards to diet, after adjusting for maternal education, children who attended less than five weeks of camp were four times more likely to eat their meals in front of the TV often/almost all of the time (OR = 4.0, 95%CI 1.0-16.2, p < 0.06). Summer activities and some dietary behaviours are influenced by situation of care and socio-demographic characteristics. In particular, children who spend a greater proportion of time in structured environments appear to be more active. We believe that this pilot study is an important first step in our understanding of what children do during the summer months.
Drosophila neurons actively regulate axonal tension in vivo.

Several experiments have shown that mechanical forces significantly influence the initiation, growth, and retraction of neurites of cultured neurons. A similar role has long been suggested for mechanical forces in vivo, but this hypothesis has remained unverified due to the paucity of in vivo studies of neuronal mechanical behavior. In this study, we used high-resolution micromechanical force sensors to study the mechanical response of motor neurons in live Drosophila embryos. Our experiments showed that Drosophila neurons maintained a rest tension (1-13 nN) and behaved like viscoelastic solids (i.e., with a linear force-deformation response followed by force relaxation to steady state) in response to sustained stretching. More importantly, when the tension was suddenly diminished by a release of the externally applied force, the neurons contracted and actively generated force to restore tension, sometimes to a value close to their rest tension. In addition, axons that were slackened by displacing the neuromuscular junction contracted and became taut in 10-30 min. These observations are remarkably similar to results from in vitro studies and suggest that mechanical tension may also strongly influence neuronal behavior in vivo.
The Contribution of Fertilizer to the Ground Water of Long Islanda

In 1973, the Suffolk County Department of Environmental Control in cooperation with Cornell University began a study on nitrogen (N) fertilization of potatoes and turfgrasses. The research and demonstration project has shown that current practices result in substantial N losses; and, in many cases, excessive use of N reduces crop yields and turf quality. Annual N losses of 50 lbs. per acre (55.5 kg-N/ha) are sufficient to cause a concentration in the aquifer's surface layer of 10 mg/1 nitrate-N (New York State Drinking Water Standard). The eastern portion of Long Island supports a productive agricultural industry whose main crop is potatoes. Ground-water surveys have shown that the aquifer system of this area is contaminated with nitrate nitrogen. The average potato grower applies 200 to 250 lb-N/a (222 to 278 kg-N/ha) at planting time; and depending upon a number of factors, N recovered in harvested tubers varies from 75 to 150 lb-N/a (83 to 167 kg-N/ha). Losses to the ground water could vary from 50 to 175 lb-N/a (55.5 to 194 kg-N/ha). The study has shown that the application of 150 lb-N/a (167 kg-N/ha) can still maintain maximum potato yields and keep the N loss to ground water below 50 lb-N/a (55.5 kg-N/ha) by improving nitrogen-use efficiency. This is done through splitting N applications so that one-third to one-half is applied at planting and the remainder is applied prior to the period of rapid crop growth and nutrient uptake. On-farm demonstration plots are being used to convince growers to reduce N rates and adopt more efficient application methods. The western portions of Long Island are highly urbanized and turfgrasses may be fertilized at rates up to 350 lb-N/a (389 kg-N/ha). Potential leaching losses are high for turfgrass as N is not recovered in harvested plant materials. Experiments are underway to establish rates of biomass N buildup under several fertilization regimes. Preliminary results indicate that N-use efficiency increases with more frequent but smaller N applications. Encouraging the use of low maintenance turf species appears to be the best long-term solution.
Shot Noise Suppression in Avalanche Photodiodes

We identify a new shot noise suppression mechanism in a thin ($\ensuremath{\sim}100\text{ }\text{ }\mathrm{nm}$) heterostructure avalanche photodiode. In the low-gain regime the shot noise is suppressed due to temporal correlations within amplified current pulses. We demonstrate in a Monte Carlo simulation that the effective excess noise factors can be $l1$, and reconcile the apparent conflict between theory and experiments. This shot noise suppression mechanism is independent of known mechanisms such as Coulomb interaction, or reflection at heterojunction interfaces.
Tutorial: Digital filtering and processing of signals

Behav. Res. Meth. & Instru., 1973, Vol. 5 (2) Digi tal filtering was described as a general mathematical technique of processing sequences of sampled data points analogous to the action of electrical or mechanical filtering. The discussion often referred to filtering as taking place in the time dimension, although it was noted that it could take place equally well in some other dimension, for example, in space. Digital filtering was described as a versatile technique that could be used in simulation, signal processing, and signal analysis with stored data or with data in real time. A complete report of the method is printed in the January 1973 (5, 21-33) issue of this Journal under the title, "Digital Filtering and Signal Processing," by J. D. Lovell, D. C. Nagel, and E. C. Carterette. Reprints may be obtained by addressing John D. Lovell, Psychology Department, California State University at Hayward, Hayward, California 94542, or Edward C. Carterette, Perceptual Systems Laboratory, Psychology Department, University of California, Los Angeles, California 90024.
Capitalism, Territory and “Marxist Geopolitics”

This response traces the importance of ideas and politics versus economic determinism in developing a critical approach to geopolitics particularly in questioning the necessary relationship between territory and capitalism. From this perspective, and contra to “Marxist geopolitics,” spatial-political form does not follow from economic function. To argue so leads to an intellectual and political dead end.
Mitobs: A seismometer system for ocean-bottom earthquake studies

The MIT ocean-bottom seismometer is a free-fall, pop-up instrument capable of recording three components of seismic data on the sea floor for periods of at least one month. Data are recorded in digital format on a specially designed magnetic tape recorder. An event recording scheme and semiconductor memories assure both efficient data storage and preservation of first motion information. Sensors and recording electronics are housed in a cylindrical pressure vessel, which sits vertically atop an expendable base plate on the ocean bottom. Attached to the pressure case are three glass spheres for buoyancy. After a pre-set time interval, a motor-driven mechanical latch release frees the instrument to float to the ocean surface for recovery.
Variations in dissolved lithium in the Mississippi River and Mississippi River estuary, Louisiana, U.S.A., during low river stage

Abstract A study of dissolved lithium in the lower Mississippi River and salt-wedge estuary during low river stage has demonstrated the existence of analytically-significant short-term variations in Li concentrations. Dissolved Li varied from 11 to 16 μg 1−1 upriver from the salt-wedge but showed no systematic variation with dissolved chloride, which varied from 18 to 30 mg 1−1. Within the salt-wedge proper, Li behaved nearly conservatively, increasing toward open marine values of 170–210 μg 1−1. Analyses of Li adsorbed on river suspended sediment indicate that Li can be introduced into solution by cation exchange during estuarine mixing. The effects of this desorption on the concentration of dissolved Li are insignificant at low river stage, however, because of low suspended-sediment concentrations.
The impact of EDI implementation commitment and implementation success on competitive advantage and firm performance

Abstract. Electronic Data Interchange Systems (EDI) are increasingly being used by business firms to improve operations and customer service. One of the major motivations for business organizations using EDI is to gain a strategic advantage in the marketplace. Although EDI has been implemented by many organizations, unfortunately not all have gained the same level of expected advantage or envisioned benefits. In this study we focus on the impact of EDI implementation commitment and implementation success on competitive advantage and firm performance. We study two categories of companies: companies that initiate the development of EDI and are known as hub companies and those that are their non-hub counterparts. Findings indicate that non-hub firms may not reap the same level of expected benefits resulting from EDI technology adoption and implementation as hub firms.
Performance of high-resolution, nonlevel bed, shallow-water models

Several techniques are investigated for extending Roe’s finite volume method to second-order spatial and temporal accuracy in order to better simulate shallow water flow over nonlevel beds. Specifically, methods reported in the literature for limiting and reconstructing dependent variables, discretizing source terms, and time stepping are examined. Steady subcritical and supercritical flow as well as unsteady flow over nonlevel beds is simulated in order to evaluate each methods’ performance in terms of error and computational effort. There is not a single method which minimizes error and computational effort for all test cases. On the contrary, methods that perform best in one application may be suboptimal in another. A general purpose modeling approach that balances accuracy against computational effort is identified and recommended.
Mitotic delay and the apparent synergism of far-red radiation and x-rays in the production of chromosomal abberations.

— The apparent synergism of far-red radiation and X-rays in the induction of chromosome aberrations has been found to be an artifact caused by a far-red-induced mitotic delay. Far red neither increases the number of X-ray-induced breaks nor decreases the amount of restitution (repair). It merely shifts the time of arrival of cells at metaphase where they can be scored. At any single given time after X-irradiation, a different population of cells will be scored if far-red as well as X-rays are given. Since various portions of the cell cycle differ in their sensitivity to X-rays, the far-red-induced mitotic delay can lead to apparent increases in aberration yields if cells are scored at only one time after X-irradiation. When the whole cell cycle is sampled, however, far-red is found not to affect the yield of aberrations.
Much Madness is Divinest Sense

Suggested citation for this article: Potter P. Much madness is divinest sense. Emerg Infect Dis [serial on the Internet]. 2008 Jul [date cited]. Available from http://www.cdc.gov/EID/content/14/7/1183.htm