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Taxonomic and gene-centric metagenomics of the fecal microbiome of low and high feed conversion ratio (FCR) broilers.  


Individual weight gain in broiler growers appears to vary, which may in part be due to variation in their gut microbiota. In this paper we analyse the fecal microbiota of low and high feed conversion ratio (FCR) broilers. After shotgun sequencing of the fecal microbiome, we used the SEED database to identify the microbial diversity and metabolic potential in low and high FCR birds. The domain-level breakdown of our samples was bacteria (>95 %), eukaryotes (>2 %), archaea (>0.2 %), and viruses (>0.2 %). At the phylum level, Proteobacteria (78.83 % in low and 52.04 % in high FCR), Firmicutes (11.97 % in low and 27.53 % in high FCR) and Bacteroidetes (7.10 % in low FCR and 17.53 % in high FCR) predominated in the fecal microbial community. Poultry fecal metagenomes revealed the sequences related to 33 genera in both low and high FCR with significantly different proportion. Functional analysis revealed that genes for the metabolism of carbohydrates, amino acids and derivatives and protein metabolism were most abundant in SEED subsystem in both samples. Genes associated with stress, virulence, cell wall and cell capsule were also abundant. Indeed, genes associated with sulphur assimilation, flagellum and flagellar motility were over represented in low FCR birds. This information could help in developing strategies to improve feed efficiency and feed formulation for broiler chickens. PMID:24136777

Singh, K M; Shah, T M; Reddy, Bhaskar; Deshpande, S; Rank, D N; Joshi, C G



Formant Centralization Ratio: A Proposal for a New Acoustic Measure of Dysarthric Speech  

ERIC Educational Resources Information Center

Purpose: The vowel space area (VSA) has been used as an acoustic metric of dysarthric speech, but with varying degrees of success. In this study, the authors aimed to test an alternative metric to the VSA--the "formant centralization ratio" (FCR), which is hypothesized to more effectively differentiate dysarthric from healthy speech and register…

Sapir, Shimon; Ramig, Lorraine O.; Spielman, Jennifer L.; Fox, Cynthia



High through put 16S rRNA gene-based pyrosequencing analysis of the fecal microbiota of high FCR and low FCR broiler growers.  


The performance of birds appears to vary among the flock of growing broilers which may in part be due to variation in their gut microbiota. In the view of poultry industry, it is desirable to minimise such variation. We investigated metagenomic profile of fecal bacteria in birds with high and low feed conversion ratio (FCR) to identify microbial community linked to low and high FCR by employing high throughput pyrosequencing of 16S rRNA genomic targets. Therefore feeding trial was investigated in order to identify fecal bacteria consistently linked with better feed conversion ratio in bird performance as measured by body weight gain. High-throughput 16S rRNA gene based pyrosequencing was used to provide a comparative analysis of fecal microbial diversity. The fecal microbial community of birds was predominated by Proteobacteria (48.04 % in high FCR and 49.98 % in low FCR), Firmicutes (26.17 % in high FCR and 36.23 % in low FCR), Bacteroidetes (18.62 % in high FCR and 11.66 % in low FCR), as well as unclassified bacteria (15.77 % in high FCR and 14.29 % in low FCR), suggesting that a large portion of fecal microbiota is novel and could be involved in currently unknown functions. The most prevalent bacterial classes in high FCR and low FCR were Gammaproteobacteria, Clostridia and Bacteroidia. However in low FCR birds Phascolarctobacterium, Faecalibacterium and Clostridium predominated among the Clostridia. In FCR comparison of fecal bacteria, about 36 genera were differentially abundant between high and low FCR birds. This information could be used to formulate effective strategies to improve feed efficiency and feed formulation for optimal gut health. PMID:23053958

Singh, K M; Shah, T; Deshpande, S; Jakhesara, S J; Koringa, P G; Rank, D N; Joshi, C G



Human FcR Polymorphism and Disease  

PubMed Central

Fc receptors play a central role in maintaining the homeostatic balance in the immune system. Our knowledge of the structure and function of these receptors and their naturally occurring polymorphisms, including single nucleotide polymorphisms and/or copy number variations, continues to expand. Through studies of their impact on human biology and clinical phenotype, the contributions of these variants to the pathogenesis, progression, and/or treatment outcome of many diseases that involve immunoglobulin have become evident. They affect susceptibility to bacterial and viral pathogens, constitute as risk factors for IgG or IgE mediated inflammatory diseases, and impact the development of many autoimmune conditions. In this chapter, we will provide an overview of these genetic variations in classical Fc?Rs, FcRLs, and other Fc receptors, as well as challenges in achieving an accurate and comprehensive understanding of the FcR polymorphisms and genomic architecture. PMID:25116105

Li, Xinrui; Gibson, Andrew W.; Kimberly, Robert P.



Can We Improve Catfish Growth and FCR Through Oxygen Management?  

Technology Transfer Automated Retrieval System (TEKTRAN)

Studies were conducted in 15 1-acre and six ¼-acre ponds over several years to determine the effect of low dissolved oxygen (DO) concentration on food conversion ratio (FCR), food consumption, growth, and net production of channel catfish. Control ponds in each study were maintained with a minimum D...


Estimation of ideal ratios of methionine and threonine to lysine in starting broiler chicks using response surface methodology.  


In a dose-response study, dietary levels of standardized ileal digestible methionine (dMet), lysine (dLys), and threonine (dThr) were optimized by response surface methodology (RSM) using a central composite rotatable design in starting broiler chicks that were feed-deprived 2 d posthatch. In total, 60 floor pens of 6 birds each were assigned to 15 diets of central composite rotatable design containing 5 levels of dMet (0.42-0.58%), dLys (0.88-1.32%), and dThr (0.53-0.87%) from 3 to 16 d of age. Experimental levels of dMet, dLys, and dThr significantly affected bird performance. The second-order models for BW gain and feed conversion ratio (FCR) were generated. The response surface analysis showed significant quadratic models for BW gain and FCR. The crossproduct of amino acids was significant for FCR but not significant for BW gain. Canonical analyses on BW gain and FCR models showed that the maximum BW gain at the stationary point may be obtained with 0.54, 1.12, and 0.78% of dMet, dLys, and dThr in the diet, respectively, and the minimum FCR at the stationary point may be obtained with 0.53, 1.13, and 0.75% of dMet, dLys, and dThr in diet, respectively. Estimated ideal ratios of dMet and dThr to dLys were 48 and 70% for BW gain and 47 and 66% for FCR. Canonical analysis revealed the most important amino acids in the models of BW gain and FCR were Lys and Thr, respectively. PMID:22334755

Mehri, M; Davarpanah, A A; Mirzaei, H R



[Evaluation of the 1Shot Phantom dedicated to the mammography system using FCR].  


Currently daily quality control (QC) tests for mammography systems are generally evaluated by using visual analysis phantoms, which of course means subjective measurement. In our study, however, we evaluated a novel digital phantom, the 1Shot Phantom M plus (1Shot Phantom), together with automatic analysis software dedicated for mammography systems using Fuji computed radiography (FCR). The digital phantom enables objective evaluation by providing for actual physical measurement rather than subjective visual assessment. We measured 1) contrast to noise ratio (CNR), 2) image receptor homogeneity, 3) missed tissue at chest wall side, 4) modulation transfer function (MTF), and 5) geometric distortion utilizing the 1Shot Phantom. We then compared the values obtained using the 1Shot Phantom with values obtained from the European guidelines and International Electrotechnical Commission (IEC) standards. In addition, we evaluated the convenience of using the digital phantom. The values utilizing the 1Shot Phantom and those from the European guidelines and IEC standards were consistent, but the QC tests for the European guidelines and IEC standards methods took about six hours while the same QC tests using the 1Shot Phantom took 10 minutes or less including exposure of the phantom image, measurement, and analysis. In conclusion, the digital phantom and dedicated software proved very useful and produced improved analysis for mammography systems using FCR in clinical daily QC testing because of their objectivity and substantial time-saving convenience. PMID:19661726

Nagashima, Chieko; Uchiyama, Nachiko; Moriyama, Noriyuki; Nagata, Mio; Kobayashi, Hiroyuki; Sankoda, Katsuhiro; Saotome, Shigeru; Tagi, Masahiro; Kusunoki, Tetsurou



First continuous measurements of CO 2 mixing ratio in central London using a compact diffusion probe  

Microsoft Academic Search

We present one year of data from the first continuous measurements of carbon dioxide mixing ratio in central London. Measurements were made at an 87m tower site using the new Vaisala CARBOCAP GMP343 instrument, which was found to provide a compact and inexpensive method for mixing ratio monitoring, in an environment where conventional CO2 sensors could not be accommodated. Measurements

Matthew Rigby; Ralf Toumi; Rebecca Fisher; David Lowry; Euan G. Nisbet



Phenology, sex ratios, and population trends of Selasphorus hummingbirds in central coastal California  

Microsoft Academic Search

From 1980 to 2000, we mist-netted 2412 Allen's Hummingbirds (Selasphorus sasin) and 203 Rufous Hummingbirds (S. rufus) at a site in central coastal California. Adult Allen's occurred from late January to early August and juveniles from early April to early September. Overall ratios of female to male Allen's were 2.5:1 for adults, 1:1.1 for juveniles. The breeding season female-to-male ratio

Steve N. G. Howell; Thomas Gardali



Tracing isospin with the {pi}{sup -}/{pi}{sup +} ratio in central heavy ion collisions  

SciTech Connect

Within an isospin- and momentum-dependent hadronic transport model, we have investigated the isospin mixing with the probe of the {pi}{sup -}/{pi}{sup +} ratio in central isospin asymmetric {sup 96}Ru+{sup 96}Zr collision at an incident energy of 400 MeV/u. The isospin equilibrium is not reached according to the asymmetrical distribution of the {pi}{sup -}/{pi}{sup +} ratio with rapidity. In comparison with the nucleon observable, it suggests that the pion ratio {pi}{sup -}/{pi}{sup +} is a promising observable to probe the relaxation of isospin degree of freedom in central heavy ion collisions without being strongly affected by the surface effect. Because of the small system size and rather strong effect of rescattering on pions, the isospin mixing shows insignificant dependence on the stiffness of the symmetry energy in the relevant colliding system.

Zhang Ming; Xiao Zhigang; Zhu Shengjiang [Department of Physics, Tsinghua University, Beijing 100084 (China)



Increased TLR responses in dendritic cells lacking the ITAM-containing adapters DAP12 and FcR?  

PubMed Central

The inhibitory effect of DAP12 on macrophages has been revealed by examining myeloid cells from DAP12-deficient mice. In this report, we demonstrate that both DAP12 and the Fc?RI?-chain (FcR?) are required for negative regulation of TLR responses in bone marrow-derived dendritic cells (DC). Loss of both DAP12 and FcR? enhanced the pro-inflammatory cytokine production and maturation of DC after TLR stimulation, resulting in a greater percentage of DC that produced IL-12 p40, TNF, and IL-6, and expressed high levels of MHC class II, CD80, and CD86. Whereas DC lacking only DAP12 showed some increased TLR responses, those lacking only FcR? had a greater enhancement of maturation and cytokine production, though to a lesser extent than DC lacking both DAP12 and FcR?. Additionally, antigen-specific T cell proliferation was enhanced by DAP12?/?FcR??/? DC relative to wild-type DC after maturation. Similar to DAP12?/?FcR??/? DC, Syk-deficient DC also had increased inflammatory cytokine production, maturation, and antigen presentation. These results confirm the inhibitory effect of immunoreceptor tyrosine-based activation motif (ITAM) signaling in myeloid cells and show that DC and macrophages differ in their dependence on the ITAM-containing adapters DAP12 and FcR? for negative regulation of TLR signaling. PMID:18081038

Chu, Ching-Liang; Yu, Yen-Ling; Shen, Kuan-Yin; Lowell, Clifford A.; Lanier, Lewis L.; Hamerman, Jessica A.



Sex ratio and reproductive activity of benthic copepods in bathyal Sagami Bay (1430 m), central Japan  

NASA Astrophysics Data System (ADS)

Sex ratios and reproductive activity of benthic copepod assemblages were investigated at the bathyal site (depth 1430 m) in Sagami Bay, central Japan. The ratio of adult females to adult males was approximately 3.5:1, significantly different from 1:1, although this parameter did not show a seasonal pattern. On the other hand, the percentage of ovigerous females among adult females and the ratio of nauplii to total copepods appeared to fluctuate seasonally in 1997 and 1998. Statistical tests, however, could not detect significant difference in either parameter. We discuss the possibility that the reproductive activity of copepods was enhanced by the increased supply of fresh phytodetritus to the sea floor.

Shimanaga, Motohiro; Shirayama, Yoshihisa



Calves' sex ratio in naturally and artificially bred cattle in central Ethiopia.  


A study was undertaken with the objective to identify some intrinsic (genotype of the cow, estrus time and parity) and extrinsic factors (service type, service time and estrus seasons) that affect calf sex ratio in naturally and artificially bred cattle in the central highlands of Ethiopia. A total of 4657 calving events were extracted from the long-term dairy cattle genetic improvement experiment at Holetta Agricultural Research Center. Factors that affect the logit of the probability of a female calf being born were obtained by using PROC GENMODE in Statistical Analysis System. Moreover, multivariate analysis was performed using PROC LOGISTIC procedure using forward selection procedure. Accordingly, genotype of the cow, parity, estrus season, and service type had considerable influences on calf sex ratio. However, estrus time and service time did not affect calf sex ratio (?(2) = 0.83 and 0.79, respectively). In Ethiopia, smallholder dairy farmers often complain that artificial insemination (AI) skewed to producing more male calves. However, our study showed that AI did not alter female-to-male calf sex ratio. On the contrary, natural mating increases the probability of female calves born (odds ratio 1.38) over AI. Heifer/cows that showed estrus and bred during the harsh seasons of the years produced more female calves than those that bred during the good seasons of the year. This strongly agreed with Trivers and Willard sex allocation theory. PMID:24908336

Delesa, Effa Kefena; Yohannes, Aster; Alemayehu, Mengistu; Samuel, Temesgen; Yehualaeshet, Teshome



Method for tuning chirp ratio of fiber gratings without central wavelength shift  

NASA Astrophysics Data System (ADS)

A method for tuning the chirp ratio of a fiber grating without the central wavelength shift is proposed by using a two-fixed-end compressive beam, which induces a linear strain distribution along the grating. This technique allows dynamic control of the grating's chirp ratio by changing the displacement of the translation stage. The 3-dB bandwidth tuning range is from 6.52 to 13.5 nm when the grating is tuned in the broadening way, while the bandwidth tuning range is from 6.52 to 0.95 nm in the compressing way. The proposed method has potential applications for the dynamic dispersion compensation and the sensors of pressure and displacement, etc., by detecting the change of bandwidth information.

Liu, Guanxiu; Feng, Dejun; Zhang, Maosen; Jia, Dongfang



Long-term results of first salvage treatment in CLL patients treated initially with FCR (fludarabine, cyclophosphamide, rituximab)  

PubMed Central

Although fludarabine, cyclophosphamide, and rituximab (FCR) together are established as a standard first-line treatment of younger patients with chronic lymphocytic leukemia (CLL), there is little information to guide the management of patients with CLL refractory to, or who have relapsed after, receiving frontline FCR treatment. To define optimal salvage strategy and identify patients unsuitable for retreatment with FCR, we examined the survival and treatment outcome of 300 patients enrolled in a phase 2 study of FCR. After a median 142 months of follow-up, 156 patients developed progressive CLL, with a median survival of 51 months after disease progression. The duration of first remission (REM1) was a key determinant of survival after disease progression and first salvage. Patients with a short REM1 (<3 years) had a short survival period, irrespective of salvage therapy received; these patients have high unmet medical needs and are good candidates for investigation of novel therapies. In patients with a long REM1 (?3 years), salvage treatment with either repeat FCR or lenalidomide-based therapy results in subsequent median survival exceeding 5 years; for these patients, FCR rechallenge represents a reasonable standard of care. PMID:25281606

Tam, Constantine S.; O’Brien, Susan; Plunkett, William; Wierda, William; Ferrajoli, Alessandra; Wang, Xuemei; Do, Kim-Anh; Cortes, Jorge; Khouri, Issa; Kantarjian, Hagop; Lerner, Susan



Tpl2 kinase regulates Fc?R signaling and immune thrombocytopenia in mice  

PubMed Central

The MAPK3 Tpl2 controls innate and adaptive immunity by regulating TLR, TNF-?, and GPCR signaling in a variety of cell types. Its ablation gives rise to an anti-inflammatory phenotype characterized by resistance to LPS-induced endotoxin shock, DSS-induced colitis, and TNF-?-induced IBD. Here, we address the role of Tpl2 in autoimmunity. Our data show that the ablation and the pharmacological inhibition of Tpl2 protect mice from antiplatelet antibody-induced thrombocytopenia, a model of ITP. Thrombocytopenia in this model and in ITP is caused by phagocytosis of platelets opsonized with antiplatelet antibodies and depends on Fc?R activation in splenic and hepatic myeloid cells. Further studies explained how Tpl2 inhibition protects from antibody-induced thrombocytopenia, by showing that Tpl2 is activated by Fc?R signals in macrophages and that its activation by these signals is required for ERK activation, cytoplasmic Ca2+ influx, the induction of cytokine and coreceptor gene expression, and phagocytosis. PMID:23898046

Kyrmizi, Irene; Ioannou, Marianna; Hatziapostolou, Maria; Tsichlis, Philip N.; Boumpas, Dimitrios T.; Tassiulas, Ioannis



Central/Peripheral fat mass ratio is associated with increased risk of hypertension in HIV-infected patients.  


The data on the risk of hypertension in human immunodeficiency virus (HIV)-infected patients, particularly in those with lipodystrophy, are controversial. The authors assessed the impact of lipodystrophy on hypertension in a cohort of HIV-infected adults receiving combination antiretroviral therapy. This was a cross-sectional study in which lipodystrophy (clinically and fat mass ratio [FMR]-defined), blood pressure, and body composition (dual-energy x-ray absorptiometry and computed tomography) were evaluated in 368 HIV adults. The prevalence of hypertension in HIV patients with or without clinically or FMR-defined lipodystrophy was similar (with clinical lipodystrophy 35.3% vs without 32.9%, not significant; with FMR lipodystrophy 41.7% vs without 32.2%, not significant). When HIV-infected patients were classified into 4 categories of fat distribution (based on the presence or absence of lipoatrophy and abdominal prominence), isolated lipoatrophy was not significantly associated with hypertension, but patients with isolated central fat accumulation and mixed forms of lipodystrophy had a significantly higher prevalence of hypertension. Hypertensive HIV patients had significantly higher total fat, central, and central/peripheral fat mass ratio than normotensive ones. After adjustment for age, sex, smoking, and body mass index, hypertension remains significantly associated with central/peripheral fat mass ratio (odds ratio, 1.258; 95% confidence interval, 1.008-1.569). Hypertension was not more prevalent in lipodystrophic HIV-infected patients, but was significantly associated with central/peripheral fat mass ratio. PMID:22947357

Freitas, Paula; Carvalho, Davide; Santos, Ana Cristina; Madureira, António José; Xerinda, Sandra; Martinez, Esteban; Pereira, Jorge; Sarmento, António; Medina, José Luís



Improved automatic adjustment of density and contrast in FCR system using neural network  

NASA Astrophysics Data System (ADS)

FCR system has an automatic adjustment of image density and contrast by analyzing the histogram of image data in the radiation field. Advanced image recognition methods proposed in this paper can improve the automatic adjustment performance, in which neural network technology is used. There are two methods. Both methods are basically used 3-layer neural network with back propagation. The image data are directly input to the input-layer in one method and the histogram data is input in the other method. The former is effective to the imaging menu such as shoulder joint in which the position of interest region occupied on the histogram changes by difference of positioning and the latter is effective to the imaging menu such as chest-pediatrics in which the histogram shape changes by difference of positioning. We experimentally confirm the validity of these methods (about the automatic adjustment performance) as compared with the conventional histogram analysis methods.

Takeo, Hideya; Nakajima, Nobuyoshi; Ishida, Masamitsu; Kato, Hisatoyo



Effects of altered Fc?R binding on antibody pharmacokinetics in cynomolgus monkeys  

PubMed Central

Antibody interactions with Fc? receptors (Fc?Rs), like Fc?RIIIA, play a critical role in mediating antibody effector functions and thereby contribute significantly to the biologic and therapeutic activity of antibodies. Over the past decade, considerable work has been directed towards production of antibodies with altered binding affinity to Fc?Rs and evaluation of how the alterations modulate their therapeutic activity. This has been achieved by altering glycosylation status at N297 or by engineering modifications in the crystallizable fragment (Fc) region. While the effects of these modifications on biologic activity and efficacy have been examined, few studies have been conducted to understand their effect on antibody pharmacokinetics (PK). We present here a retrospective analysis in which we characterize the PK of three antibody variants with decreased Fc?R binding affinity caused by amino acid substitutions in the Fc region (N297A, N297G, and L234A/L235A) and three antibody variants with increased Fc?RIIIA binding affinity caused by afucosylation at N297, and compare their PK to corresponding wild type antibody PK in cynomolgus monkeys. For all antibodies, PK was examined at a dose that was known to be in the linear range. Since production of the N297A and N297G variants in Chinese hamster ovary cells results in aglycosylated antibodies that do not bind to Fc?Rs, we also examined the effect of expression of an aglycosylated antibody, without sequence change(s), in E. coli. All the variants demonstrated similar PK compared with that of the wild type antibodies, suggesting that, for the six antibodies presented here, altered Fc?R binding affinity does not affect PK. PMID:24492343

Leabman, Maya K; Meng, Y Gloria; Kelley, Robert F; DeForge, Laura E; Cowan, Kyra J; Iyer, Suhasini




EPA Science Inventory

The report is the first in a series of four, documenting research performed under EPA's Fundamental Combustion Research (FCR) program. It is divided in two: Part A is a program overview and an introduction to the series; and Part B documents research performed in the gas-phase ch...


The relationship between accommodative amplitude and the ratio of central lens thickness to its equatorial diameter in vertebrate eyes  

PubMed Central

Aim To determine the relationship between accommodative amplitude and central lens thickness/equatorial lens diameter (CLT/ELD) ratio in vertebrates. Methods Midsagittal sections of lenses from fixed, post mortem eyes from 125 different vertebrate species were photographed. Their CLT/ELD ratios were correlated with independently published measurements of their accommodative amplitudes. Using the non?linear finite element method (FEM), the efficiency of zonular traction (the absolute change in central radius of curvature per unit force [|?CR|/F]) for model lenses with CLT/ELD ratios from 0.45 to 0.9 was determined. Results Vertebrates with CLT/ELD ratios ?0.6 have high accommodative amplitudes. Zonular traction was found to be most efficient for those model lenses having CLT/ELD ratios ?0.6. Conclusions Vertebrates with lenses that have CLT/ELD ratios ?0.6 – i.e. “long oval” shapes – have the greatest accommodative amplitudes; e.g. primates, diving birds and diurnal birds of prey. Vertebrates that have oval or spherical shaped lenses, like owls and most mammals, have low accommodative amplitudes. Zonular traction was found to be most efficient when applied to model lenses with CLT/ELD ratios ?0.6. The implications of these findings on the mechanism of accommodation are discussed. PMID:17050574

Schachar, Ronald A; Pierscionek, Barbara K; Abolmaali, Ali; Le, Tri



Intake-to-delivered-energy ratios for central station and distributed electricity generation in California  

Microsoft Academic Search

In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a

Garvin A. Heath; William W. Nazaroff



Search for Quark Compositeness with the Dijet Centrality Ratio in pp Collisions at sqrt[s]=7??????TeV  

SciTech Connect

A search for quark compositeness in the form of quark contact interactions, based on hadronic jet pairs (dijets) produced in proton-proton collisions at sqrt(s)=7 TeV, is described. The data sample of the study corresponds to an integrated luminosity of 2.9 inverse picobarns collected with the CMS detector at the LHC. The dijet centrality ratio, which quantifies the angular distribution of the dijets, is measured as a function of the invariant mass of the dijet system and is found to agree with the predictions of the Standard Model. A statistical analysis of the data provides a lower limit on the energy scale of quark contact interactions. The sensitivity of the analysis is such that the expected limit is 2.9 TeV; because the observed value of the centrality ratio at high invariant mass is below the expectation, the observed limit is 4.0 TeV at the 95% confidence level.

Khachatryan, Vardan; et al.



Search for quark compositeness with the dijet centrality ratio in pp collisions at ?s=7 TeV.  


A search for quark compositeness in the form of quark contact interactions, based on hadronic jet pairs (dijets) produced in proton-proton collisions at ?s=7 TeV, is described. The data sample of the study corresponds to an integrated luminosity of 2.9 pb(-1) collected with the CMS detector at the LHC. The dijet centrality ratio, which quantifies the angular distribution of the dijets, is measured as a function of the invariant mass of the dijet system and is found to agree with the predictions of the standard model. A statistical analysis of the data provides a lower limit on the energy scale of quark contact interactions. The sensitivity of the analysis is such that the expected limit is 2.9 TeV; because the observed value of the centrality ratio at high invariant mass is below the expectation, the observed limit is 4.0 TeV at the 95% confidence level. PMID:21231646

Khachatryan, V; Sirunyan, A M; Tumasyan, A; Adam, W; Bergauer, T; Dragicevic, M; Erö, J; Fabjan, C; Friedl, M; Frühwirth, R; Ghete, V M; Hammer, J; Hänsel, S; Hartl, C; Hoch, M; Hörmann, N; Hrubec, J; Jeitler, M; Kasieczka, G; Kiesenhofer, W; Krammer, M; Liko, D; Mikulec, I; Pernicka, M; Rohringer, H; Schöfbeck, R; Strauss, J; Taurok, A; Teischinger, F; Waltenberger, W; Walzel, G; Widl, E; Wulz, C-E; Mossolov, V; Shumeiko, N; Gonzalez, J Suarez; Benucci, L; Ceard, L; De Wolf, E A; Janssen, X; Maes, T; Mucibello, L; Ochesanu, S; Roland, B; Rougny, R; Selvaggi, M; Van Haevermaet, H; Van Mechelen, P; Van Remortel, N; Adler, V; Beauceron, S; Blyweert, S; D'Hondt, J; Devroede, O; Kalogeropoulos, A; Maes, J; Maes, M; Tavernier, S; Van Doninck, W; Van Mulders, P; Van Onsem, G P; Villella, I; Charaf, O; Clerbaux, B; De Lentdecker, G; Dero, V; Gay, A P R; Hammad, G H; Hreus, T; Marage, P E; Thomas, L; Vander Velde, C; Vanlaer, P; Wickens, J; Costantini, S; Grunewald, M; Klein, B; Marinov, A; Ryckbosch, D; Thyssen, F; Tytgat, M; Vanelderen, L; Verwilligen, P; Walsh, S; Zaganidis, N; Basegmez, S; Bruno, G; Caudron, J; De Favereau De Jeneret, J; Delaere, C; Demin, P; Favart, D; Giammanco, A; Grégoire, G; Hollar, J; Lemaitre, V; Militaru, O; Ovyn, S; Pagano, D; Pin, A; Piotrzkowski, K; Quertenmont, L; Schul, N; Beliy, N; Caebergs, T; Daubie, E; Alves, G A; De JesusDamiao, D; Pol, M E; Souza, M H G; Carvalho, W; Da Costa, E M; Martins, C De Oliveira; De Souza, S Fonseca; Mundim, L; Nogima, H; Oguri, V; Goicochea, J M Otalora; Da Silva, W L Prado; Santoro, A; Do Amaral, S M Silva; Sznajder, A; De Araujo, F Torres Da Silva; Dias, F A; Dias, M A F; Tomei, T R Fernandez Perez; Gregores, E M; Marinho, F; Novaes, S F; Padula, Sandra S; Darmenov, N; Dimitrov, L; Genchev, V; Iaydjiev, P; Piperov, S; Rodozov, M; Stoykova, S; Sultanov, G; Tcholakov, V; Trayanov, R; Vankov, I; Dyulendarova, M; Hadjiiska, R; Kozhuharov, V; Litov, L; Marinova, E; Mateev, M; Pavlov, B; Petkov, P; Bian, J G; Chen, G M; Chen, H S; Jiang, C H; Liang, D; Liang, S; Wang, J; Wang, J; Wang, X; Wang, Z; Yang, M; Zang, J; Zhang, Z; Ban, Y; Guo, S; Hu, Z; Li, W; Mao, Y; Qian, S J; Teng, H; Zhu, B; Cabrera, A; Moreno, B Gomez; Rios, A A Ocampo; Oliveros, A F Osorio; Sanabria, J C; Godinovic, N; Lelas, D; Lelas, K; Plestina, R; Polic, D; Puljak, I; Antunovic, Z; Dzelalija, M; Brigljevic, V; Duric, S; Kadija, K; Morovic, S; Attikis, A; Fereos, R; Galanti, M; Mousa, J; Nicolaou, C; Ptochos, F; Razis, P A; Rykaczewski, H; Abdel-basit, A; Assran, Y; Mahmoud, M A; Hektor, A; Kadastik, M; Kannike, K; Müntel, M; Raidal, M; Rebane, L; Azzolini, V; Eerola, P; Czellar, S; Härkönen, J; Heikkinen, A; Karimäki, V; Kinnunen, R; Klem, J; Kortelainen, M J; Lampén, T; Lassila-Perini, K; Lehti, S; Lindén, T; Luukka, P; Mäenpää, T; Tuominen, E; Tuominiemi, J; Tuovinen, E; Ungaro, D; Wendland, L; Banzuzi, K; Korpela, A; Tuuva, T; Sillou, D; Besancon, M; Dejardin, M; Denegri, D; Fabbro, B; Faure, J L; Ferri, F; Ganjour, S; Gentit, F X; Givernaud, A; Gras, P; de Monchenault, G Hamel; Jarry, P; Locci, E; Malcles, J; Marionneau, M; Millischer, L; Rander, J; Rosowsky, A; Titov, M; Verrecchia, P; Baffioni, S; Bianchini, L; Bluj, M; Broutin, C; Busson, P; Charlot, C; Dobrzynski, L; de Cassagnac, R Granier; Haguenauer, M; Miné, P; Mironov, C; Ochando, C; Paganini, P; Sabes, D; Salerno, R; Sirois, Y; Thiebaux, C; Wyslouch, B; Zabi, A; Agram, J-L; Andrea, J; Besson, A; Bloch, D; Bodin, D; Brom, J-M; Cardaci, M; Chabert, E C; Collard, C; Conte, E; Drouhin, F; Ferro, C; Fontaine, J-C; Gelé, D; Goerlach, U; Greder, S; Juillot, P; Karim, M; Le Bihan, A-C; Mikami, Y; Van Hove, P; Fassi, F; Mercier, D; Baty, C; Beaupere, N; Bedjidian, M; Bondu, O; Boudoul, G; Boumediene, D; Brun, H; Chanon, N; Chierici, R; Contardo, D; Depasse, P; El Mamouni, H; Falkiewicz, A; Fay, J; Gascon, S; Ille, B; Kurca, T; Le Grand, T; Lethuillier, M; Mirabito, L; Perries, S; Sordini, V; Tosi, S; Tschudi, Y; Verdier, P; Xiao, H; Roinishvili, V; Anagnostou, G; Edelhoff, M; Feld, L; Heracleous, N; Hindrichs, O; Jussen, R; Klein, K; Merz, J; Mohr, N; Ostapchuk, A; Perieanu, A; Raupach, F; Sammet, J; Schael, S; Sprenger, D; Weber, H; Weber, M; Wittmer, B; Ata, M; Bender, W; Erdmann, M; Frangenheim, J; Hebbeker, T; Hinzmann, A; Hoepfner, K; Hof, C; Klimkovich, T; Klingebiel, D; Kreuzer, P; Lanske, D; Magass, C; Masetti, G; Merschmeyer, M; Meyer, A; Papacz, P; Pieta, H; Reithler, H; Schmitz, S A; Sonnenschein, L; Steggemann, J; Teyssier, D; Bontenackels, M; Davids, M; Duda, M; Flügge, G; Geenen, H; Giffels, M; Ahmad, W Haj; Heydhausen, D; Kress, T; Kuessel, Y; Linn, A; Nowack, A; Perchalla, L; Pooth, O; Rennefeld, J; Sauerland, P; Stahl, A; Thomas, M; Tornier, D; Zoeller, M H; Martin, M Aldaya; Behrenhoff, W; Behrens, U; Bergholz, M; Borras, K; Cakir, A; Campbell, A; Castro, E



Broadly neutralizing hemagglutinin stalk–specific antibodies require Fc?R interactions for protection against influenza virus in vivo  

PubMed Central

Neutralizing antibodies against influenza viruses have traditionally been thought to provide protection exclusively through their variable region; the contributions of mechanisms conferred by the Fc domain remain controversial. We investigated the in vivo contributions of Fc interactions with their cognate receptors for a collection of neutralizing anti-influenza antibodies. Whereas five broadly neutralizing monoclonal antibodies (bNAbs) targeting the conserved stalk region of hemagglutinin (HA) required interactions between the antibody Fc and Fc receptors for IgG (Fc?Rs) to confer protection from lethal H1N1 challenge, three strain-specific monoclonal Abs (mAbs) against the variable head domain of HA were equally protective in the presence or absence of Fc?R interactions. Although all antibodies blocked infection, only anti-stalk bNAbs were capable of mediating cytotoxicity of infected cells, which accounts for their Fc?R dependence. Immune complexes generated with anti–HA stalk mAb efficiently interacted with Fc?Rs, but anti–HA head immune complexes did not. These results suggest that Fc?R binding capacity by anti-HA antibodies was dependent on the interaction of the cognate Fab with antigen. We exploited these disparate mechanisms of mAb-mediated protection to reengineer an anti-stalk bNAb to selectively enhance Fc?R engagement to augment its protective activity. These findings reveal a previously uncharacterized property of bNAbs and guide an approach toward enhancing mAb-mediated antiviral therapeutics. PMID:24412922

DiLillo, David J; Tan, Gene S; Palese, Peter; Ravetch, Jeffrey V



Response to selection for feed conversion ratio in Japanese quail.  


We investigated the effect of selection for 4-wk feed conversion ratio (FCR) on genetic improvement of FCR, BW, weight gain (WG), feed intake (FI), and residual FI (RFI) in Japanese quail. The F line was selected for reduced FCR and the C line was maintained as a randombred control. In each generation, 35 sires and 70 dams were used as parents for the next generation. Three generations of selection were performed. Realized heritability for FCR was calculated as the ratio of cumulative selection response to the cumulative selection differential, and additionally, genetic response was quantified as the difference between the means of selection and control lines. The results showed that realized heritability for FCR after 3 generations of selection was 0.67. The mean FCR in F line and C line in the last generation was 2.13 and 2.61, respectively. This is 18.4% cumulative genetic improvement, or 6.1% improvement per generation. In the last generation, the means of F and C lines were 193 and 166 g for BW at age 28 d (16.4% total increase, or 5.5% per generation), 184 and 158 g for WG (17.2% total higher gain and 5.7% per generation), 393 and 413 g for FI (4.9% total higher consumption and 1.6% per generation), and -24.5 and 10.2 for RFI (-34.7 g of cumulative gain; -11.6 g per generation), respectively. These results show that selection to decrease FCR increases BW and WG and decreases FI and RFI as a correlated response. PMID:20634511

Varkoohi, S; Moradi Shahr Babak, M; Pakdel, A; Nejati Javaremi, A; Zaghari, M; Kause, A



High aspect ratio template and method for producing same for central and peripheral nerve repair  

NASA Technical Reports Server (NTRS)

Millimeter to nano-scale structures manufactured using a multi-component polymer fiber matrix are disclosed. The use of dissimilar polymers allows the selective dissolution of the polymers at various stages of the manufacturing process. In one application, biocompatible matrixes may be formed with long pore length and small pore size. The manufacturing process begins with a first polymer fiber arranged in a matrix formed by a second polymer fiber. End caps may be attached to provide structural support and the polymer fiber matrix selectively dissolved away leaving only the long polymer fibers. These may be exposed to another product, such as a biocompatible gel to form a biocompatible matrix. The polymer fibers may then be selectively dissolved leaving only a biocompatible gel scaffold with the pores formed by the dissolved polymer fibers. The scaffolds may be used in, among other applications, the repair of central and peripheral nerves. Scaffolds for the repair of peripheral nerves may include a reservoir for the sustained release of nerve growth factor. The scaffolds may also include a multifunctional polyelectrolyte layer for the sustained release of nerve growth factor and enhance biocompatibility.

Sakamoto, Jeff S. (Inventor); Tuszynski, Mark Henry (Inventor); Gros, Thomas (Inventor); Chan, Christina (Inventor); Mehrotra, Sumit (Inventor)



Is radio jet power linearly proportional to the product of central black hole mass and Eddington ratio in AGN?  

NASA Astrophysics Data System (ADS)

A model for the relation between radio jet power and the product of central black hole (BH) mass and Eddington ratio of AGN is proposed, and the model is examined with data from the literature. We find that radio jet power positively correlates but not linearly with the product of BH mass ( m in solar mass) and Eddington ratio ( ?), and the power law indices ( ?) are significantly less than unity for relatively low accretion ( ?<0.1) AGN, P j ?( ?m) ? , in the radio galaxies and the Seyfert galaxies. This leads to a negative correlation between radio loudness and ?m for the low luminosity AGN, i.e. R?( ?m) ? with ?=(7/6) ?-1<0, which may be attributed to a contribution of BH spin to total jet power assuming that the spin induced jet is gradually suppressed as the accretion rate increases. Whereas, for the high- z quasars which often show the slope ??1, a positive correlation between the radio loudness and disc luminosity is predicted. We discuss that the jet powers of the high- z FRII quasars are likely dominated by the accretion disc rather than by the BH spin.

Liu, Xiang; Han, Zhenhua



Direct Measurement of Initial 230TH/ 232TH Ratios in Central Texas Speleothems for More Accurate Age Determination  

NASA Astrophysics Data System (ADS)

Speleothems, calcite deposits in caves, preserve a record of climate in their growth rate, isotope ratios and trace element concentrations. These variables must be tied to precise ages to produce pre-instrumental records of climate. The 238U-234U- 230Th disequilibrium method of dating can yield precise ages if the amount of 230Th from the decay of radiogenic 238U can be constrained. 230Th in a speleothem calcite growth layer has two potential sources - 1) decay of radioactive 238U since the time of growth of the calcite layer; and 2) initial detrital 230Th, incorporated along with detrital 232Th, into the calcite layer at the time it grew. Although the calcite lattice does not typically incorporate Th, samples can contain impurities with relatively high Th contents. Initial 230Th/232Th is commonly estimated by assuming a source with bulk-Earth U/Th values in a state of secular equilibrium in the 238U-decay chain. The uncertainty in this 230Th/232Th estimate is also assumed, typically at +/-100%. Both assumptions contribute to uncertainty in ages determined for young speleothems. If the amount of initial detrital 230Th can be better quantified for samples or sites, then U-series ages will have smaller uncertainties and more precisely define the time series of climate proxies. This study determined the initial 230Th/232Th of modern calcite to provide more precise dates for central Texas speleothems. Calcite was grown on glass-plate substrates placed under active drips in central Texas caves. The 230Th/232Th of this modern calcite was determined using thermal ionization mass spectrometry. Results show that: 1) initial 230Th/232Th ratios can be accurately determined in these young samples and 2) measuring 230Th/232Th reduces the uncertainties in previously-determined ages on stalagmites from under the same drips. For example, measured initial 230Th/232Th in calcite collected on substrates from different locations in the cave at Westcave Preserve are 15.3 × 0.67 ppm, 14.6 × 0.83 ppm, 5.8 × 0.56 ppm, and 5.9 × 0.60 ppm, which are higher and more precise than the value commonly assumed for initial 230Th/232Th, 4.4 × 4.4 ppm. Soil sampled above Westcave, a potential source of detrital Th incorporated into speleothems, also has a high calculated 230Th/232Th. We calculate soil 230Th/232Th from measured U and Th concentrations of soil leachates (using DI water and ammonium acetate). Calculated 230Th/232Th for Westcave soils range from 0.39 to 28.4 ppm, which encompasses the range of initial 230Th/232Th values found in the modern calcite. Soil leachates from Natural Bridge Caverns and Inner Space Cavern were analyzed by the same method, yielding calculated 230Th/232Th ranging from 1.5 to 12.6 ppm (Natural Bridge), and from 1.43 to 272 ppm (Inner Space). Soil and calcite data indicate that the commonly assumed initial 230Th/232Th is not always applicable and that initial 230Th/232Th can be estimated more accurately by measuring Th isotope ratios in modern calcite and soils to determine speleothem U-series ages.

Wortham, B. E.; Banner, J. L.; James, E.; Loewy, S. L.



Recognition of water masses according to geochemical signatures in the Central Mediterranean sea: Y\\/Ho ratio and rare earth element behaviour  

Microsoft Academic Search

This study reports the results of geochemical investigations carried out in the Strait of Sicily (Central Mediterranean Sea) during the oceanographic cruise BANSIC 2000, focusing on the area around the Pantelleria Island. We evaluate the interface processes between dissolved phase and suspended particulate matter in the water columns on the basis of Y\\/Ho ratio and rare earth elements and yttrium

P. Censi; P. Zuddas; D. Larocca; F. Saiano; F. Placenti; A. Bonanno



18 O\\/ 16 O ratios in ash-flow tuffs and lavas erupted from the central Nevada caldera complex and the central San Juan caldera complex, Colorado  

Microsoft Academic Search

Oxygen isotope compositions were measured on 129 quartz, feldspar, and biotite phenocrysts from ash-flow tuffs and lava domes erupted from the Oligocene central Nevada and central San Juan caldera complexes. Most of the ash-flow tuffs are compositionally zoned with low-phenocryst rhyolite bases and high-phenocryst quartz-latite tops, but both within individual units and throughout each of the eruptive sequences at each

Peter B. Larson; Hugh P. Taylor



Ligation of the FcR Chain-Associated Human Osteoclast-Associated Receptor Enhances the Proinflammatory Responses of Human Monocytes and Neutrophils1  

Microsoft Academic Search

We have previously described the human osteoclast associated receptor (hOSCAR), expressed in all cells of the myeloid lineage, and its immune functions. This receptor, which associates with the FcR chain to transduce an activating signal, induces calcium flux in monocytes and dendritic cells, and modulates specific responses of dendritic cells. In this study, we have examined the effects of hOSCAR

Estelle Merck; Claude Gaillard; Mathieu Scuiller; Patrizia Scapini; Marco A. Cassatella; Giorgio Trinchieri; Elizabeth E. M. Bates


A PKC-SHP1 signaling axis desensitizes Fc? receptor signaling by reducing the tyrosine phosphorylation of CBL and regulates Fc?R mediated phagocytosis  

PubMed Central

Background Fc? receptors mediate important biological signals in myeloid cells including the ingestion of microorganisms through a process of phagocytosis. It is well-known that Fc? receptor (Fc?R) crosslinking induces the tyrosine phosphorylation of CBL which is associated with Fc?R mediated phagocytosis, however how signaling molecules coordinate to desensitize these receptors is unclear. An investigation of the mechanisms involved in receptor desensitization will provide new insight into potential mechanisms by which signaling molecules may downregulate tyrosine phosphorylation dependent signaling events to terminate important signaling processes. Results Using the U937IF cell line, we observed that Fc?R1 crosslinking induces the tyrosine phosphorylation of CBL, which is maximal at 5 min. followed by a kinetic pattern of dephosphorylation. An investigation of the mechanisms involved in receptor desensitization revealed that pretreatment of U937IF or J774 cells with PMA followed by Fc? receptor crosslinking results in the reduced tyrosine phosphorylation of CBL and the abrogation of downstream signals, such as CBL-CRKL binding, Rac-GTP activation and the phagocytic response. Pretreatment of J774 cells with GF109203X, a PKC inhibitor was observed to block dephosphorylation of CBL and rescued the phagocytic response. We demonstrate that the PKC induced desensitization of Fc?R/ phagocytosis is associated with the inactivation of Rac-GTP, which is deactivated in a hematopoietic specific phosphatase SHP1 dependent manner following ITAM stimulation. The effect of PKC on Fc?R signaling is augmented by the transfection of catalytically active SHP1 and not by the transfection of catalytic dead SHP1 (C124S). Conclusions Our results suggest a functional model by which PKC interacts with SHP1 to affect the phosphorylation state of CBL, the activation state of Rac and the negative regulation of ITAM signaling i.e. Fc? receptor mediated phagocytosis. These findings suggest a mechanism for Fc? receptor desensitization by which a serine-threonine kinase e.g. PKC downregulates tyrosine phosphorylation dependent signaling events via the reduced tyrosine phosphorylation of the complex adapter protein, CBL. PMID:24886428



Plasmacytoid dendritic cells, interferon signaling, and Fc?R contribute to pathogenesis and therapeutic response in childhood immune thrombocytopenia.  


Immune thrombocytopenia (ITP) is an autoimmune disorder of childhood characterized by immune-mediated destruction of platelets. The mechanisms underlying the pathogenesis of ITP and the therapeutic efficacy of intravenous immunoglobulins (IVIG) in this disorder remain unclear. We show that monocytes from patients with ITP have a distinct gene expression profile, with increased expression of type I interferon response (IR) genes. Plasma from ITP patients had increased levels of several cytokines indicative of immune activation, including an increase in interferon-?. ITP patients also had an increase in plasmacytoid dendritic cells (pDCs) compared to healthy donors. Therapy-induced remission of ITP was associated with abrogation of the IR gene signature in monocytes without reduction in the levels of circulating interferon-? itself. IVIG altered the ratio of activating/inhibitory Fc? receptors (Fc?Rs) in vivo primarily by reducing Fc?RIII (CD16). The engagement of activating Fc?Rs was required for IVIG-mediated abrogation of monocyte response to exogenous interferon-? in culture. Moreover, plasma from ITP patients led to activation of monocytes and myeloid DCs in culture with an increase in T cell stimulatory capacity; this activation depended on the engagement of activating Fc?Rs and interferon-? receptor (IFNAR) and was inhibited by antibody-mediated blockade of these pathways. These data point to a central role of type I interferon in the pathogenesis of ITP and suggest targeting pDCs and blockade of IR as potential therapeutic approaches in this disorder. They also provide evidence for the capacity of IVIG to extinguish IR in vivo, which may contribute to its effects in autoimmunity. PMID:23843450

Sehgal, Kartik; Guo, Xiuyang; Koduru, Srinivas; Shah, Anumeha; Lin, Aiping; Yan, Xiting; Dhodapkar, Kavita M



Alteration effects of volcanic ash in seawater: Anomalous Y/Ho ratios in coastal waters of the Central Mediterranean sea  

NASA Astrophysics Data System (ADS)

This paper presents the results of a study based on data collected during the oceanographic cruise ANSIC 2001 carried out in the Ionian Sea during the explosive activity of Mount Etna in the summer of 2001. Anomalous low values of Y/Ho ratios in seawater suggest extensive scavenging processes on the surfaces of smectitic alteration products, with Y and Ho fractionation controlled by the differences in their electronic configurations and behaviour during solution/surface complexation equilibria. These processes can also be traced through the presence of significant tetrad effects recorded in the chondrite-normalised Rare Earth Elements and Yttrium (YREEs) patterns of suspended particulate matter. This suggests that the preferential Y scavenging from seawater is due to the formation of inner-sphere complexes with OH - groups on montmorillonite crystal surfaces. The preliminary results of kinetic experiments of YREE released from volcanic ash to coexisting seawater, and the related effects on Y/Ho ratios and Ce anomalies, are consistent with the fractionation of Light Rare Earth Elements (LREEs) with respect to Heavy Rare Earth Elements (HREEs) observed in dissolved phase. They suggest a behaviour of Y similar to that reported for LREEs, particularly for Ce and Pr.

Censi, P.; Sprovieri, M.; Larocca, D.; Aricò, P.; Saiano, F.; Mazzola, S.; Ferla, P.



Temporal evolution of lead isotope ratios in sediments of the Central Portuguese Margin: a fingerprint of human activities.  


Stable Pb isotope ratios ((206)Pb/(207)Pb, (208)Pb/(206)Pb), (210)Pb, Pb, Al, Ca, Fe, Mn and Si concentrations were measured in 7 sediment cores from the west coast of the Iberian Peninsula to assess the Pb contamination throughout the last 200 years. Independently of their locations, all cores are characterized by increasing Pb/Al rends not related to grain-size changes. Conversely, decreasing trends of (206)Pb/(207)Pb were found towards the present. This tendency suggest a change in Pb sources reflecting an increased proportion derived from anthropogenic activities. The highest anthropogenic Pb inventories for sediments younger than 1950s were found in the two shallowest cores of Cascais and Lisboa submarine canyons, reflecting the proximity of the Tagus estuary. Lead isotope signatures also help demonstrate that sediments contaminated with Pb are not constrained to estuarine-coastal areas and upper parts of submarine canyons, but are also to transferred to a lesser extent to deeper parts of the Portuguese Margin. PMID:23871578

Mil-Homens, Mário; Caetano, Miguel; Costa, Ana M; Lebreiro, Susana; Richter, Thomas; de Stigter, Henko; Trancoso, Maria A; Brito, Pedro



Deciphering petrogenic processes using Pb isotope ratios from time-series samples at Bezymianny and Klyuchevskoy volcanoes, Central Kamchatka Depression  

NASA Astrophysics Data System (ADS)

The Klyuchevskoy group of volcanoes in the Kamchatka arc erupts compositionally diverse magmas (high-Mg basalts to dacites) over small spatial scales. New high-precision Pb isotope data from modern juvenile (1956-present) erupted products and hosted enclaves and xenoliths from Bezymianny volcano reveal that Bezymianny and Klyuchevskoy volcanoes, separated by only 9 km, undergo varying degrees of crustal processing through independent crustal columns. Lead isotope compositions of Klyuchevskoy basalts-basaltic andesites are more radiogenic than Bezymianny andesites (208Pb/204Pb = 37.850-37.903, 207Pb/204Pb = 15.468-15.480, and 206Pb/204Pb = 18.249-18.278 at Bezymianny; 208Pb/204Pb = 37.907-37.949, 207Pb/204Pb = 15.478-15.487, and 206Pb/204Pb = 18.289-18.305 at Klyuchevskoy). A mid-crustal xenolith with a crystallization pressure of 5.2 ± 0.6 kbars inferred from two-pyroxene geobarometry and basaltic andesite enclaves from Bezymianny record less radiogenic Pb isotope compositions than their host magmas. Hence, assimilation of such lithologies in the middle or lower crust can explain the Pb isotope data in Bezymianny andesites, although a component of magma mixing with less radiogenic mafic recharge magmas and possible mantle heterogeneity cannot be excluded. Lead isotope compositions for the Klyuchevskoy Group are less radiogenic than other arc segments (Karymsky—Eastern Volcanic Zone; Shiveluch—Northern Central Kamchatka Depression), which indicate increased lower-crustal assimilation beneath the Klyuchevskoy Group. Decadal timescale Pb isotope variations at Klyuchevskoy demonstrate rapid changes in the magnitude of assimilation at a volcanic center. Lead isotope data coupled with trace element data reflect the influence of crustal processes on magma compositions even in thin mafic volcanic arcs.

Kayzar, Theresa M.; Nelson, Bruce K.; Bachmann, Olivier; Bauer, Ann M.; Izbekov, Pavel E.



Genetic relationships between feed conversion ratio, growth curve and body composition in slow-growing chickens.  


1. Relationships between feed conversion ratio, growth curve parameters and carcase composition were investigated on 1061 chickens from a slow-growing line of label-type chickens. The growth curve was modelled with the Gompertz function. Individual feed conversion ratio (FCR) was recorded between 8 and 10 weeks of age and residual feed consumption (RES) was calculated over the same interval. Abdominal fat yield (AFY), breast yield (BRY) and leg yield (LY) were also measured on the birds following slaughter at 75 d of age. 2. The means for FCR and RES were 3.15 and 0.62 g, respectively. Growth curve parameters were 0.141/d for initial specific growth rate (L), 0.031/d for maturation rate (K) and 48.9 d for age at inflexion (TI). Mean values for BRY, LY and AFY were 166, 306 and 40 g/kg, respectively. 3. Heritability of FCR and RES were moderate to high (0.33 and 0.38 to 0.45). Growth curve parameters and LY were moderately heritable (0.22 to 0.34) and BRY and AFY were highly heritable (0.50 and 0.66). Genetic correlations between growth curve parameters and either FCR or RES were low to moderate (-0.31 to 0.51). LY and AFY were highly correlated with FCR (-0.70 and 0.44) and RES (-0.32 and 0.44) but BRY was not (0.00 and -0.35). These results show that indirect selection for feed conversion ratio is possible by using growth curve parameters and abdominal fatness, which do not require rearing the chickens in cages. PMID:16787850

N'Dri, A L; Mignon-Grasteau, S; Sellier, N; Tixier-Boichard, M; Beaumont, C



Low-affinity Fc?R interactions can decide the fate of novel human IgG-sensitised red blood cells and platelets.  


G1?nab is a mutant human IgG1 constant region with a lower ability to interact with Fc?R than the natural IgG constant regions. Radiolabelled RBCs and platelets sensitised with specific G1?nab Abs were cleared more slowly from human circulation than IgG1-sensitised counterparts. However, non-destructive splenic retention of G1?nab-coated RBCs required investigation and plasma radioactivities now suggest this also occurred for platelets sensitised with an IgG1/G1?nab mixture. In vitro assays with human cells showed that G1?nab-sensitised RBCs did not cause Fc?RI-mediated monocyte activation, Fc?RIIIa-mediated antibody-dependent cell-mediated cytotoxicity (ADCC) or macrophage phagocytosis although they did adhere to macrophages. Thus, Fc?RII was implicated in the adhesion despite the ?nab mutation reducing the already low-affinity binding to this receptor class. Additional contacts via P-selectin enhance the interaction of sensitised platelets with monocytes and this system provided evidence of Fc?RII-dependent activation by G1?nab. These results emphasise the physiological relevance of low-affinity interactions: It appears that Fc?RII interactions of G1?nab allowed splenic retention of G1?nab-coated RBCs with inhibitory Fc?RIIb binding preventing RBC destruction and that Fc?RIIb engagement by G1?nab on IgG1/G1?nab-sensitised platelets overcame activation by IgG1. Considering therapeutic blocking Abs, G1?nab offers lower Fc?R binding and a greater bias towards inhibition than IgG2 and IgG4 constant regions. PMID:24285214

Armour, Kathryn L; Smith, Cheryl S; Turner, Craig P; Kirton, Christopher M; Wilkes, Anthony M; Hadley, Andrew G; Ghevaert, Cedric; Williamson, Lorna M; Clark, Michael R



Neutrophils in autoantibody-mediated arthritis: critical producers of FcR? , the receptor for C5a, and LFA-1  

PubMed Central

Objective Neutrophils represent a prominent component of inflammatory joint effusions and are required for synovial inflammation in mouse models, but mechanisms are poorly understood. We developed a system to test the importance of production of specific factors by neutrophils in a mouse model of arthritis. Methods Neutrophil-deficient Gfi-1?/? mice were sub-lethally irradiated, then engrafted with donor bone-marrow cells (BMC), which resulted in production of mature neutrophils within two weeks. By reconstituting with BMC from mice lacking selected pro-inflammatory factors, mice specifically lacking these factors on neutrophils were generated. Arthritis was initiated by transfer of K/BxN serum to identify the role of defined neutrophil factors on arthritis incidence and severity. Results Neutrophils lacking the signaling chain of stimulatory Fc receptors (FcR? ?/?) were unable to elicit arthritis, but neutrophils lacking Fc? RIII still did so. Neutrophils lacking the chemotactic or adhesion receptors C5aR or CD11a/LFA-1 also failed to initiate arthritis but could enter joints in which inflammation had been initiated by wild-type neutrophils. Neutrophils unable to produce interleukin-1 ? and ? (IL-1?? ?/?) or leukotrienes (5-LO?/?) produced arthritis of intermediate severity. Inability of neutrophils to make tumor necrosis factor (TNF), or to express receptors for TNF or IL-1, had no effect on arthritis. Conclusion A novel transfer system was developed to identify neutrophil production of FcR? , C5aR, and CD11a/LFA-1 as critical components of autoantibody-mediated arthritis. Neutrophil production of IL-1 and leukotriene B4 likely contributes to inflammation but is not essential. Molecular requirements for neutrophil influx into joints become more permissive after inflammation is initiated. PMID:20191628

Monach, Paul A; Nigrovic, Peter A; Chen, Mei; Hock, Hanno; Lee, David M; Benoist, Christophe; Mathis, Diane



From emissions to ambient mixing ratios: online seasonal field measurements of volatile organic compounds over a Norway spruce-dominated forest in central Germany  

NASA Astrophysics Data System (ADS)

Biogenic volatile organic compounds (BVOCs) are substantial contributors to atmospheric chemistry and physics and demonstrate the close relationship between biosphere and atmosphere. Their emission rates are highly sensitive to meteorological and environmental changes with concomitant impacts on atmospheric chemistry. We have investigated seasonal isoprenoid and oxygenated VOC (oxVOC) fluxes from a Norway spruce (Picea abies) tree in central Germany and explored the emission responses under various atmospheric conditions. Emission rates were quantified by using dynamic branch enclosure and proton-transfer-reaction mass spectrometry (PTR-MS) techniques. Additionally, ambient mixing ratios were derived through application of a new box model treatment on the dynamic chamber measurements. These are compared in terms of abundance and origin with the corresponding emissions. Isoprenoids dominate the BVOC emissions from Norway spruce, with monoterpenes and sesquiterpenes accounting for 50.8 ± 7.2% and 19.8 ± 8.1% respectively of the total emissions. Normalizing the VOC emission rates, we have observed a trend of reduction of carbon-containing emissions from April to November, with an enhancement of oxVOC. Highest emission rates were observed in June for all measured species, with the exception of sesquiterpenes, which were emitted most strongly in April. Finally, we evaluate the temperature-dependent algorithm that seems to describe the temperature-dependent emissions of methanol, acetaldehyde and monoterpenes but only with the use of the monthly derived values for emission potential, Es, and temperature dependency, ? factor.

Bourtsoukidis, E.; Williams, J.; Kesselmeier, J.; Jacobi, S.; Bonn, B.



The Ambystoma laterale-jeffersonianum Complex in Central Ontario: Ploidy Structure, Sex Ratio, and Breeding Dynamics in a Bisexual-Unisexual Community  

E-print Network

populations of the Ambystoma laterale-jeffersonianumcomplex bycollecting blood fromindividual salamanders, near the northern limit of hybrid biotypes, these account for much of the biased sex ratio. Timing

Murphy, Bob


First measurement of the ratio of central-electron to forward-electron W partial cross sections in pp[over] collisions at (square root)s =1.96 TeV.  


We present a measurement of sigma(pp[over] --> W) x B(W --> e nu) at (square root)s = 1.96 TeV, using electrons identified in the forward region (1.2 < |eta| < 2.8) of the CDF II detector, in 223 pb(-1) of data. We measure sigma x B = 2796 +/- 13(stat)(-90)(+95)(syst) +/- 162(lum) pb. Combining this result with a previous CDF measurement obtained using electrons in the central region (|eta| approximately < 1), we present the first measurement of the ratio of central-electron to forward-electron W partial cross sections R(exp) = 0.925 +/- 0.006(stat) +/- 0.032(syst), consistent with theoretical predictions using Coordinated Theoretical-Experimental Project on QCD (CTEQ) and Martin-Roberts-Stirling-Thorne (MRST) parton distribution functions. PMID:17678012

Abulencia, A; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carillo, S; Carlsmith, D; Carosi, R; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Cilijak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Almenar, C Cuenca; Cuevas, J; Culbertson, R; Cully, J C; DaRonco, S; Datta, M; D'Auria, S; Davies, T; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; De Lorenzo, G; Dell'Orso, M; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Giovanni, G P Di; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Dörr, C; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraan, A C; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis, A; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moon, C S; Moore, R; Morello, M; Fernandez, P Movilla; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J



Sensitivity of stable isotope ratios of tree-rings of Silver fir (Abies alba Mill.) in Franconia (Central Germany) to climate and environmental changes  

NASA Astrophysics Data System (ADS)

We constructed 1000-year long carbon and oxygen isotope chronologies of Silver fir (Abies alba Mill.) from the temperate region of Franconia (northern Bavaria, Central Germany) with the aim to carry out the climate reconstructions by using of multivariate models. The annual variations of isotope signals in firs were strong influenced by airborne pollutants in the second half of 20th century: the linear responses of 13C; 18O and 2H signals to SO2, O3 and dust concentrations were high significant. Therefore, we used the long meteorological data set, were the disturbed period could be excluded for climate reconstructions. In this case, carbon isotopes correspond most to spring/summer climate conditions as April to August mean temperatures and June/July precipitation amount, oxygen show the strongest correlation to the July relative air humidity and to the April to August mean temperatures. The correlations between tree-ring signals and summer climate are high (p

Boettger, T.; Haupt, M.; Friedrich, M.



Central Nervous System Effects of the Second-Generation Antihistamines Marketed in Japan -Review of Inter-Drug Differences Using the Proportional Impairment Ratio (PIR)-  

PubMed Central

Background Second-generation antihistamines (AHs) have, in general, fewer sedative effects than the first-generation. However, important inter-drug differences remain in the degree of cognitive and/or psychomotor impairment. The extent to which a particular compound causes disruption can be conveniently compared, to all other AHs, using the Proportional Impairment Ratio (PIR). Although the PIR can differentiate the relative impairment caused by individual drugs, there is no indication of the reliability of the ratios obtained. Objective To calculate the PIRs –together with 95% confidence intervals (CIs), as an index of reliability– and compare AHs currently, or soon to be, available in Japan, with respect to their intrinsic capacity to cause impairment. Methods Results from studies of cetirizine, desloratadine, ebastine, fexofenadine, levocetirizine, loratadine, mequitazine, and olopatadine were included in the PIR calculations. All data utilised came from crossover studies in healthy volunteers which were randomised and placebo and positive-internal controlled. Existing databases from studies reporting the sedative effects of AHs on objective (speed, accuracy, memory) and subjective (feeling) psychometrics were augmented, via results from suitable studies published after the previous reviews. The null value for a PIR was one. Results A total of 45 studies were finally included for this review. Of the AHs assessed, fexofenadine, ebastine, and levocetirizine showed a PIR for objective tests of 0. However, only fexofenadine (PIR?=?0.49) had an upper limit of the 95% CI of less than 1. Fexofenadine, levocetirizine, desloratadine, olopatadine, loratadine, and mequitazine all had a PIR for subjective ratings of 0, but the upper limits of the 95% CIs were all in excess of 1, although fexofenadine (PIR?=?2.57) was the lowest. Conclusions The results show that there are differences between second-generation AHs in the extent of sedation produced. However, subjective ratings indicate that patients may not necessarily be aware of this. PMID:25501360

Isomura, Tatsuya; Kono, Takeshi; Hindmarch, Ian; Kikuchi, Norimasa; Murakami, Aya; Inuzuka, Kyoko; Kawana, Seiji



Lipid D/H Ratios from Multiple Sources and Deposits Indicate Drier Little Ice Age at Washington Island (4°43`N, 160°25`W), Central Pacific  

NASA Astrophysics Data System (ADS)

To compare the sensitivity of biomarker D/H ratios from two distinct climate archives, a lake and a peat bog on the Tropical Pacific Island of Terrania, compound-specific hydrogen isotope ratios (expressed as ?D values) were determined on lipid biomarkers from various biological sources deposited in the two climate archives. At present, Terrania or Washington Island (4°43`N, 160°25`W) permanently lies in the intertropical convergence zone (ITCZ) and receives an annual precipitation of 2,903 mm. The interior of this lens shaped island contains a freshwater lake and peat bogs. Previous studies on the lake sediments found evidence for a substantially drier climate at times during the Little Ice Age (AD 1400-1850) based on the lithologic transition from modern freshwater sediments to a sequence of pure cyanobacterial mat in concert with ?D values from total lipid extracts (Sachs et al., 2009). Here we report on ?D values from lipids of various sources: dinoflagellate algae (dinosterol and a saturated C30 sterol (4? -methyl-24-ethyl-5? -cholestan-3?-ol), microbial sources (diploptene and nC21 alkane) and higher plants (fern-7-ene, ?-sitosterol and stigmastanol). Mean ?D values from all lipids, measured in both archives, are significantly enriched in deuterium by between 22 and 86‰ during previously inferred drier climate conditions and simultaneously record the transition towards a freshwater lake at around AD1550. Measured ?D values of all lipids cover a wide range from -281‰ to -105‰ during freshwater deposition and from -185‰ to -50‰ when climate was drier. In agreement with the observed isotopic difference between lipids produced via the acetogenic and the mevalonic acid biosynthetic pathway ?D values for algae and higher plant sterols are depleted in deuterium relative to the nC21 alkane by 150‰ on average. The consistent ?D values from dinosterol and 4? -methyl-24-ethyl-5? -cholestan-3?-ol from the lake and peat deposits signify the robustness of these lipid ?D values to indicate hydrologic changes in the sedimentary record. ?D values among lipids of similar and disparate sources and/or biosynthetic origin from Washington Island lake (AD ~ 800-1550) and peat bog (AD~1200-1660) sediments are significantly enriched in deuterium prior to AD 1560/1640 and thus both suggest drier climate conditions resembling today’s environmental and depositional setting at Christmas Island which is located 300km SSE of Washington Island beyond the influence of the ITCZ.

Muegler, I.; Sachse, D.; Sachs, J. P.



Reconstructing C3 and C4 vegetation cover using n-alkane carbon isotope ratios in recent lake sediments from Cameroon, Western Central Africa  

NASA Astrophysics Data System (ADS)

Trees and shrubs in tropical Africa use the C3 cycle as a carbon fixation pathway during photosynthesis, while grasses and sedges mostly use the C4 cycle. Leaf-wax lipids from sedimentary archives such as the long-chain n-alkanes (e.g., n-C27 to n-C33) inherit carbon isotope ratios that are representative of the carbon fixation pathway. Therefore, n-alkane ?13C values are often used to reconstruct past C3/C4 composition of vegetation, assuming that the relative proportions of C3 and C4 leaf waxes reflect the relative proportions of C3 and C4 plants. We have compared the ?13C values of n-alkanes from modern C3 and C4 plants with previously published values from recent lake sediments and provide a framework for estimating the fractional contribution (areal-based) of C3 vegetation cover (fC3) represented by these sedimentary archives. Samples were collected in Cameroon, across a latitudinal transect that accommodates a wide range of climate zones and vegetation types, as reflected in the progressive northward replacement of C3-dominated rain forest by C4-dominated savanna. The C3 plants analysed were characterised by substantially higher abundances of n-C29 alkanes and by substantially lower abundances of n-C33 alkanes than the C4 plants. Furthermore, the sedimentary ?13C values of n-C29 and n-C31 alkanes from recent lake sediments in Cameroon (-37.4‰ to -26.5‰) were generally within the range of ?13C values for C3 plants, even when from sites where C4 plants dominated the catchment vegetation. In such cases simple linear mixing models fail to accurately reconstruct the relative proportions of C3 and C4 vegetation cover when using the ?13C values of sedimentary n-alkanes, overestimating the proportion of C3 vegetation, likely as a consequence of the differences in plant wax production, preservation, transport, and/or deposition between C3 and C4 plants. We therefore tested a set of non-linear binary mixing models using ?13C values from both C3 and C4 vegetation as end-members. The non-linear models included a sigmoid function (sine-squared) that describes small variations in the fC3 values as the minimum and maximum ?13C values are approached, and a hyperbolic function that takes into account the differences between C3 and C4 plants discussed above. Model fitting and the estimation of uncertainties were completed using the Monte Carlo algorithm and can be improved by future data addition. Models that provided the best fit with the observed ?13C values of sedimentary n-alkanes were either hyperbolic functions or a combination of hyperbolic and sine-squared functions. Such non-linear models may be used to convert ?13C measurements on sedimentary n-alkanes directly into reconstructions of C3 vegetation cover.

Garcin, Yannick; Schefuß, Enno; Schwab, Valérie F.; Garreta, Vincent; Gleixner, Gerd; Vincens, Annie; Todou, Gilbert; Séné, Olivier; Onana, Jean-Michel; Achoundong, Gaston; Sachse, Dirk



Lightning Ratios  

NSDL National Science Digital Library

Using satellites and ground-based detection instruments, researchers have now mapped out lightning ratios for the continental United States. The Lightning Ratios site, from Space Science News (NASA), provides recent data in the form of a vibrant color map (.pdf or .jpg) of cloud-to-cloud lightning to cloud-to-ground lightning over the continental United States.


Rod Ratios  

NSDL National Science Digital Library

This activity builds student knowledge of ratios by using Cuisenaire rods to determine proportion and form equivalent ratios. Students may use the Cuisenaire rod environment embedded in this resource or they may use actual Cuisenaire rods depending on preference/ability/accessibility. This resource includes teacher notes, solution, and suggestions for questioning.

Team, Nrich




E-print Network

., 10 am­4 pm 2 China Moon Restaurant 121 Central Park Sq. 662-2883 Chinese, Thai, and vegetarian. Mon am­3 pm Sat.­Sun., 7 am­3 pm 8 El Parasol 1903 Central Avenue 661-0303 Native New Mexican food. Mon, hamburgers, and New Mexican food. Tues.­Fri., 6 am­1 pm Sat., 7 am­noon Closed Sunday & Monday 11 Sonic Drive



E-print Network

Sun., 10 am­4 pm 2 China Moon Restaurant 121 Central Park Sq. 662-2883 Chinese, Thai, and vegetarian Mexican food. Mon.­Fri., 7 am­6 pm Sat., 8 am­2 pm; Sun., 9 am­2 pm 9 Home Run Pizza 1627 Central Avenue-7591 Breakfast burritos, hamburgers, and New Mexican food. Tues.­Fri., 6 am­1 pm Sat., 7 am­noon Closed Sunday


Feeding of by-products completely replaced cereals and pulses in dairy cows and enhanced edible feed conversion ratio.  


When fed human-edible feeds, such as grains and pulses, dairy cows are very inefficient in transforming them into animal products. Therefore, strategies to reduce human-edible inputs in dairy cow feeding are needed to improve food efficiency. The aim of this feeding trial was to analyze the effect of the full substitution of a common concentrate mixture with a by-product concentrate mixture on milk production, feed intake, blood values, and the edible feed conversion ratio (eFCR), defined as human-edible output per human edible input. The experiment was conducted as a change-over design, with each experimental period lasting for 7 wk. Thirteen multiparous and 5 primiparous Holstein cows were randomly assigned to 1 of 2 treatments. Treatments consisted of a grass silage-based forage diet supplemented with either conventional ingredients or solely by-products from the food processing industry (BP). The BP mixture had higher contents of fiber and ether extract, whereas starch content was reduced compared with the conventional mixture. Milk yield and milk solids were not affected by treatment. The eFCR in the BP group were about 4 and 2.7 times higher for energy and protein, respectively. Blood values did not indicate negative effects on cows' metabolic health status. Results of this feeding trial suggest that by-products could replace common concentrate supplements in dairy cow feeding, resulting in an increased eFCR for energy and protein which emphasizes the unique role of dairy cows as net food producers. PMID:25483200

Ertl, P; Zebeli, Q; Zollitsch, W; Knaus, W



Completion of the ORNL Fuel Cycle Research and Development (FCR&D) Level 4 Milestone – Sigma Team – Off-Gas – ORNL – FT-14OR031202, MS# M4FT-14OR0312027, “Support to PNNL Kr-85 Preliminary Optimization Study”, due May 30, 2014  

SciTech Connect

This letter and attached emails document the completion of the FCR&D Level 4 milestone for the Sigma Team – Off-Gas – ORNL work package (FT-14OR031202), “Support to PNNL Kr-85 Preliminary Optimization Study” (M4FT-14OR0312027), due May 30, 2014. Support to this effort included providing a literature search and providing a significant number of reference documents covering more than 30 years of past work on Kr recovery, recovery system designs, and past cost analyses. In addition, ORNL provided support on several conference calls to establish an analysis approach for the current study and to review progress.

Jubin, Robert T. [ORNL] [ORNL



Ratios and Proportions  

NSDL National Science Digital Library

In this learning object from Wisc-Online, students will examine ratios and proportions. The unit's activities include defining ratios and proportions, simplifying ratios, solving problems using proportions and answering practice questions.

Blohowiak, Chad; Jensen, Douglas; Reed, Allen



The Golden Ratio  

ERIC Educational Resources Information Center

The Golden Ratio is sometimes called the "Golden Section" or the "Divine Proportion", in which three points: A, B, and C, divide a line in this proportion if AC/AB = AB/BC. "Donald in Mathmagicland" includes a section about the Golden Ratio and the ratios within a five-pointed star or pentagram. This article presents two computing exercises that…

Hyde, Hartley



Bicycle Gears- Ratios  

NSDL National Science Digital Library

Students experiment with and learn about the gear ratios on a bicycleâthus enhancing their understanding of circumference of a circle, proportions, etc. Actual gear ratio would be the ratio between the front and rear sprocket, NOT between pedal and rear wheel.



The Strehl Ratio in Adaptive Optics Images: Statistics and Estimation  

E-print Network

Statistical properties of the intensity in adaptive optics images are usually modeled with a Rician distribution. We study the central point of the image, where this model is inappropriate for high to very high correction levels. The central point is an important problem because it gives the Strehl ratio distribution. We show that the central point distribution can be modeled using a non-central Gamma distribution.

Rémi Soummer; André Ferrari



Compression Ratio Adjuster  

NASA Technical Reports Server (NTRS)

New mechanism alters compression ratio of internal-combustion engine according to load so that engine operates at top fuel efficiency. Ordinary gasoline, diesel and gas engines with their fixed compression ratios are inefficient at partial load and at low-speed full load. Mechanism ensures engines operate as efficiently under these conditions as they do at highload and high speed.

Akkerman, J. W.



Likelihood Ratio Tests  

NSDL National Science Digital Library

This page, created by Kyle Siegrist of the University of Alabama - Huntsville, introduces likelihood ratio tests by giving the Neyman-Pearson lemma and several examples. The examples include a gamma model, a binomial model, and a nonparametric model. The page concludes with a definition of the generalized likelihood ratio test.

Siegrist, Kyle


Ratio and Fractions.  

ERIC Educational Resources Information Center

Findings on ratio and on fractions from a research project on strategies and errors in secondary mathematics are discussed, with typical errors described. Pupils seemed to learn rules without understanding. (MNS)

Hart, K.



Isotope Ratio Mass Spectrometry.  


Isotope Ratio Mass Spectrometry (IRMS) is a specialized technique used to provide information about the geographic, chemical, and biological origins of substances. The ability to determine the source of an organic substance stems from the relative isotopic abundances of the elements which comprise the material. Because the isotope ratios of elements such as carbon, hydrogen, oxygen, sulfur, and nitrogen can become locally enriched or depleted through a variety of kinetic and thermodynamic factors, measurement of the isotope ratios can be used to differentiate between samples which otherwise share identical chemical compositions. Several sample introduction methods are now available for commercial isotope ratio mass spectrometers. Combustion is most commonly used for bulk isotopic analysis, whereas gas and liquid chromatography are predominately used for the real-time isotopic analysis of specific compounds within a mixture. Here, highlights of advances in instrumentation and applications within the last three years are provided to illustrate the impact of this rapidly growing area of research. Some prominent new applications include authenticating organic food produce, ascertaining whether or not African elephants are guilty of night-time raids on farmers' crops, and linking forensic drug and soil samples from a crime scene to a suspected point of origin. For the sake of brevity, we focus this Minireview on the isotope ratio measurements of lighter-elements common to organic sources; we do not cover the equally important field of inorganic isotope ratio mass spectrometry. PMID:19173039

Muccio, Zeland; Jackson, Glen P



Cicada Central  

NSDL National Science Digital Library

This site, hosted by University of Connecticut, "is designed to be a center for the exchange of scientific information concerning cicadas of the world." This Cicada Central website links to reprints for scientific literature concerning cicadas, a list of cicada researchers from around the world, a list of world cicada tribes, and more.

Simon, Chris


Engineering Central  

NSDL National Science Digital Library

The Engineering Central website provides a plethora of listings of employment resources for engineers. The website allows users to submit their resume to a resume bank, browse through entry-level jobs, as well as post jobs online. Several links that point to other engineering resources are also provided.



Central Limit Theorem Worksheet 2  

E-print Network

- the angle of incidence versus the angle of refraction - based on the ratio of the velocities of light of refraction in water is 2, then = sin 2 sin 1 where is the velocity of light in water as a fractionCentral Limit Theorem Worksheet 2 1. Snell's law tell us how light bends at an interface

Watkins, Joseph C.


IPO Central  

NSDL National Science Digital Library

IPO (Initial Public Offerings) Central, provided by The Reference Press, contains a wealth of information on IPOs. It features a complete list of companies that "filed for an initial public offering of common stock on or after May 6, 1996, the first day that all US companies were required to file electronically," along with EDGAR Online SEC filings. This directory can be accessed alphabetically or by date, and the latest filings are available under a separate menu item. IPO Central also highlights one featured IPO per week, with a free link to a Hoover Online profile on that company. "The Insider" offers short analytical columns on IPOs, and the "Beginner's Guide" has links to basic IPO information to help the novice. The site also offers links to other IPO-related sites. IPO Central does not at this time offer a searchable interface to its directory, but the providers promise improved search features soon. Note that listings are removed from the directory after six months and that EDGAR Online is in no way related to SEC (Securities and Exchange Commission) EDGAR.


Area Ratios of Quadrilaterals.  

ERIC Educational Resources Information Center

Shows that the ratio of the area of the quadrilateral formed by joining the kth points to the area of the original quadrilateral is constant whether it is convex or concave quadrilateral. Presents many geoboard or dot paper diagrams and geometrical expresssions. (YP)

Anderson, David R.; Arcidiacono, Michael J.



The Likelihood Ratio Test  

NSDL National Science Digital Library

This module, created by Don Johnson of Rice University, provides an explanation and an example of the likelihood ratio test. Topics include: decision regions, Bayes' decision criterion, Bayes' cost, and likelihood function. The site is enhanced by Johnson's use of graphic and numerical demonstrations to better explain his points. Additionally, a PDF attachment providing an in-depth explanation is also featured.

Johnson, Don


Digit ratio in birds.  


The Homeobox (Hox) genes direct the development of tetrapod digits. The expression of Hox genes may be influenced by endogenous sex steroids during development. Manning (Digit ratio. New Brunswick, NJ: Rutgers University Press, 2002) predicted that the ratio between the lengths of digits 2 (2D) and 4 (4D) should be sexually dimorphic because prenatal exposure to estrogens and androgens positively influence the lengths of 2D and 4D, respectively. We measured digits and other morphological traits of birds from three orders (Passeriformes, house sparrow, Passer domesticus; tree swallow, Tachycineta bicolor; Pscittaciformes, budgerigar, Melopsittacus undulates; Galliformes, chicken, Gallus domesticus) to test this prediction. None were sexually dimorphic for 2D:4D and there were no associations between 2D:4D and other sexually dimorphic traits. When we pooled data from all four species after we averaged right and left side digits from each individual and z-transformed the resulting digit ratios, we found that males had significantly larger 2D:4D than did females. Tetrapods appear to be sexually dimorphic for 2D:4D with 2D:4D larger in males as in some birds and reptiles and 2D:4D smaller in males as in some mammals. The differences between the reptile and mammal lineages in the directionality of 2D:4D may be related to the differences between them in chromosomal sex determination. We suggest that (a) natural selection for a perching foot in the first birds may have overridden the effects of hormones on the development of digit ratio in this group of vertebrates and (b) caution be used in making inferences about prenatal exposure to hormones and digit ratio in birds. PMID:18833568

Lombardo, Michael P; Thorpe, Patrick A; Brown, Barbara M; Sian, Katie



Neuropsychology Central  

NSDL National Science Digital Library

Neuropsychology Central is devoted to the subject of - "Neuropsychology, a new branch of science with the specific and unique aim of investigating the role of individual brain systems in complex forms of mental activity." - A.R. Luria "The Working Brain" The page aims to describe the importance of neuropsychology as a science of brain and behavior, and to act as a resource for the professional and layperson alike. See links to current technology for brain imaging, and sections covering different aspects of this ever growing field such as cognitive, developmental, and geriatric Neuropsychology. In addition, a reader survey is included to facilitate the expansion of the site.

Browndyke, J. N.



Sonnet Central  

NSDL National Science Digital Library

Created by a dedicated sonnet aficionado, Sonnet Central is not intended for the scholar, per se, but for the reader, the Internaut with a weakness for poetry. The site contains a collection of English-language sonnets, grouped by period and region or by author, and modernized for contemporary readers. Pictures, contemporaneous critical works, a bibliography, and audio files of readings of selected poems complement the sonnets, some of which are maintained off-site (many at the University of Toronto). From Shakespeare to Wilfred Owen, selections from many well-known sonneteers are here alongside those of their less famous contemporaries.


Central pain.  


Questions from patients about pain conditions and analgesic pharmacotherapy and responses from authors are presented to help educate patients and make them more effective self-advocates. The topic addressed in this issue is central pain, a neuropathic pain syndrome caused by a lesion in the brain or spinal cord that sensitizes one's perception of pain. It is a debilitating condition caused by various diseases such as multiple sclerosis, strokes, spinal cord injuries, or brain tumors. Varied symptoms and the use of pharmacological medicines and nonpharmacological therapies will be addressed. PMID:25295639

Singh, Supreet



What's My Ratio?  

NSDL National Science Digital Library

In this activity, students use linear measurement and calculators to investigate proportionality and determine the constant ratio between similar figures. In it, students draw a figure on centimeter graph paper, increase or decrease the size, and predict the dimensions. Then students compare the ratio of two pictures by measuring, recording their data, and discussing their findings to draw conclusions. Suggested guidelines for instruction and classroom discussion are included, as well as data collection worksheets for students, and centimeter graph paper to print. The lesson may be introduced by reading appropriate sections from "GoosebumpsâMonster Blood III" (Chapters 15 and 16) by R.L. Stine, or "The Shrinking of Treehorn" by F. Heide.



Displacement and Velocity Ratios  

NSDL National Science Digital Library

This interactive presentation, created by James Bourassa and John Rosz for the Electromechanical Digital Library, discusses displacement and velocity ratios. Bourassa and Rosz begin by providing detailed definitions of both topics and then provide mathematical examples of each. Once this basic explanation is complete, the authors allow students to practice these theories in a set of self-correcting quiz questions. Bourassa and Rosz explain each using helpful interactive flash animations. These are not only useful in explanation, but they allow the student to more fully engage with the topic. Overall, this is a nice introduction to the physical and mathematical concepts of displacement and velocity ratios. This could be a valuable learning resource in everything from a physics to a technical education classroom.

Bourassa, James; Rosz, John



Odor Concentration Invariance by Chemical Ratio Coding  

PubMed Central

Many animal species rely on chemical signals to extract ecologically important information from the environment. Yet in natural conditions chemical signals will frequently undergo concentration changes that produce differences in both level and pattern of activation of olfactory receptor neurons. Thus, a central problem in olfactory processing is how the system is able to recognize the same stimulus across different concentrations. To signal species identity for mate recognition, some insects use the ratio of two components in a binary chemical mixture to produce a code that is invariant to dilution. Here, using psychophysical methods, we show that rats also classify binary odor mixtures according to the molar ratios of their components, spontaneously generalizing over at least a tenfold concentration range. These results indicate that extracting chemical ratio information is not restricted to pheromone signaling and suggest a general solution for concentration-invariant odor recognition by the mammalian olfactory system. PMID:18958244

Uchida, Naoshige; Mainen, Zachary F.



Ratios and Proportions  

NSDL National Science Digital Library

This interactive slideshow explains the notion of ratios and proportions, how to write the, and how to find them. There are practice problems which walk visitors through each step of the process, including reducing answers to simplest terms, in which students are asked to calculate the rate of grass seed coverage per square foot and find the miles per gallon fuel use of a car. The lesson continues on to introduce proportion and work through practice problems in the same fashion.

Jensen, Douglas; Reed, Allen



Ratios, Proportions, Similarity  

NSDL National Science Digital Library

This is a set of four, one-page problems about the size of planets compared to earth. Learners may use ratios to compare planets within our solar system or those outside of our solar system with the earth. Options are presented so that students may learn about the MESSENGER mission to Mercury through a NASA press release or by viewing a NASA eClips video [6 min.]. This activity is part of the Space Math multi-media modules that integrate NASA press releases, NASA archival video, and mathematics problems targeted at specific math standards commonly encountered in middle school.



Central Pain Syndrome  


NINDS Central Pain Syndrome Information Page Table of Contents (click to jump to sections) What is Central Pain Syndrome? Is there ... being done? Clinical Trials Organizations What is Central Pain Syndrome? Central pain syndrome is a neurological condition ...


Analysis of Ratios in Multivariate Morphometry  

PubMed Central

The analysis of ratios of body measurements is deeply ingrained in the taxonomic literature. Whether for plants or animals, certain ratios are commonly indicated in identification keys, diagnoses, and descriptions. They often provide the only means for separation of cryptic species that mostly lack distinguishing qualitative characters. Additionally, they provide an obvious way to study differences in body proportions, as ratios reflect geometric shape differences. However, when it comes to multivariate analysis of body measurements, for instance, with linear discriminant analysis (LDA) or principal component analysis (PCA), interpretation using body ratios is difficult. Both techniques are commonly applied for separating similar taxa or for exploring the structure of variation, respectively, and require standardized raw or log-transformed variables as input. Here, we develop statistical procedures for the analysis of body ratios in a consistent multivariate statistical framework. In particular, we present algorithms adapted to LDA and PCA that allow the interpretation of numerical results in terms of body proportions. We first introduce a method called the “LDA ratio extractor,” which reveals the best ratios for separation of two or more groups with the help of discriminant analysis. We also provide measures for deciding how much of the total differences between individuals or groups of individuals is due to size and how much is due to shape. The second method, a graphical tool called the “PCA ratio spectrum,” aims at the interpretation of principal components in terms of body ratios. Based on a similar idea, the “allometry ratio spectrum” is developed which can be used for studying the allometric behavior of ratios. Because size can be defined in different ways, we discuss several concepts of size. Central to this discussion is Jolicoeur's multivariate generalization of the allometry equation, a concept that was derived only with a heuristic argument. Here we present a statistical derivation of the allometric size vector using the method of least squares. The application of the above methods is extensively demonstrated using published data sets from parasitic wasps and rock crabs. PMID:21828084

Baur, Hannes; Leuenberger, Christoph



Peak power ratio generator  


A peak power ratio generator is described for measuring, in combination with a conventional power meter, the peak power level of extremely narrow pulses in the gigahertz radio frequency bands. The present invention in a preferred embodiment utilizes a tunnel diode and a back diode combination in a detector circuit as the only high speed elements. The high speed tunnel diode provides a bistable signal and serves as a memory device of the input pulses for the remaining, slower components. A hybrid digital and analog loop maintains the peak power level of a reference channel at a known amount. Thus, by measuring the average power levels of the reference signal and the source signal, the peak power level of the source signal can be determined.

Moyer, Robert D. (Albuquerque, NM)



Trace ratio problem revisited.  


Dimensionality reduction is an important issue in many machine learning and pattern recognition applications, and the trace ratio (TR) problem is an optimization problem involved in many dimensionality reduction algorithms. Conventionally, the solution is approximated via generalized eigenvalue decomposition due to the difficulty of the original problem. However, prior works have indicated that it is more reasonable to solve it directly than via the conventional way. In this brief, we propose a theoretical overview of the global optimum solution to the TR problem via the equivalent trace difference problem. Eigenvalue perturbation theory is introduced to derive an efficient algorithm based on the Newton-Raphson method. Theoretical issues on the convergence and efficiency of our algorithm compared with prior literature are proposed, and are further supported by extensive empirical results. PMID:19304481

Jia, Yangqing; Nie, Feiping; Zhang, Changshui



Ratio and Proportion  

NSDL National Science Digital Library

This interactive Flash applet helps students explore concepts of ratio and proportion. It displays two containers, each with its own tap that can be set to deliver different-colored liquids in units of 1 to 10. A main tap can be set to deliver multiples of the amounts on the left- and right-hand taps. Proportion can be modelled using the drain container, which receives whatever is in the left- and right-hand containers. Users can choose the capacity of the containers, whether to hide or show the scales, and the size and visibility of the drain container. Clicking on the info button allows users to mouse over items to learn about them. This applet lends itself well for use with an interactive white board. A pdf guide to this collection of teaching applets is cataloged separately.



Dietary L-arginine supplement alleviates hepatic heat stress and improves feed conversion ratio of Pekin ducks exposed to high environmental temperature.  


The current intensive indoor production system of commercial Pekin ducks never allows adequate water for swimming or wetting. Therefore, heat stress is a key factor affecting health and growth of ducks in the hot regions and season. Experiment 1 was conducted to study whether heat stress was deleterious to certain organs of ducks. Forty-one-day-old mixed-sex Pekin ducks were randomly allocated to four electrically heated battery brooders comprised of 10 ducks each. Ducks were suddenly exposed to 37 °C ambient temperature for 3 h and then slaughtered, in one brooder at 21 days and in another brooder at 49 days of age. The results showed that body weight and weight of immune organs, particularly liver markedly decreased in acute heat stress ducks compared with the control. Experiment 2 was carried out to investigate the influences of dietary L-arginine (Arg) supplement on weight and compositions of certain lymphoid organs, and growth performance in Pekin ducks, under daily cyclic hot temperature environment. A total of 151-day-old mixed-sex Pekin ducks were randomly divided into one negative control and two treatment groups, fed experimental diets supplemented with 0, 5, and 10 g L-Arginine (L-Arg)/kg to the basal diet respectively. Ducks were exposed to cyclic high temperature simulating natural summer season. The results showed that the addition of L-Arg improves feed conversion ratio (FCR) during a period of 7-week trial, as well as increases hepatic weight relative to body weight at 21 days, while decreases the hepatic water content at 49 days of age. This study indicated that the liver was more sensitive to acute heat stress, and the hepatic relative weight and chemical composition could be regulated by dietary L-Arg supplementation in Pekin ducks being reared at high ambient temperature. These beneficial effects of Arg on liver might be a cause of improved FCR. PMID:24773570

Zhu, W; Jiang, W; Wu, L Y



Debate Central  

NSDL National Science Digital Library

Courtesy of the National Center for Policy Analysis (NCPA), offers resources related to this year's National Forensic League high school debate topic: "Resolved: That the United States federal government should establish a foreign policy significantly limiting the use of weapons of mass destruction." The site, which is updated daily, features a wealth of links sorted into ten categories (each of which is further divided into subcategories). Resources are collected from periodicals, think tanks, and other sources, and the collection should be useful not just for debaters but for anyone looking for authoritative resources on these topics. Other debate topics are listed on the right-hand side of the page, though these are covered in a less comprehensive manner. Also at the site is a bulletin board, through which users can ask questions of experts such as Dr. Hans Mark, former Secretary of the Air Force and Deputy Administrator of NASA, and a link to NCPA's Terrorism in America site. NCPA's mission is "to develop and promote private alternatives to government regulation and control, solving problems by relying on the strength of the competitive, entrepreneurial private sector."



CO (Carbon Monoxide Mixing Ratio System) Handbook  

SciTech Connect

The main function of the CO instrument is to provide continuous accurate measurements of carbon monoxide mixing ratio at the ARM SGP Central Facility (CF) 60-meter tower (36.607 °N, 97.489 °W, 314 meters above sea level). The essential feature of the control and data acquisition system is to record signals from a Thermo Electron 48C and periodically calibrate out zero and span drifts in the instrument using the combination of a CO scrubber and two concentrations of span gas (100 and 300 ppb CO in air). The system was deployed on May 25, 2005.

Biraud, S



Energy Profit Ratio Compared  

SciTech Connect

We need more oil energy to take out oil under the ground. Limit resources make us consider other candidates of energy source instead of oil. Electricity shall be the main role more and more like electric vehicles and air conditioners so we should consider electricity generation ways. When we consider what kind of electric power generation is the best or suitable, we should not only power generation plant but whole process from mining to power generation. It is good way to use EPR, Energy Profit Ratio, to analysis which type is more efficient and which part is to do research and development when you see the input breakdown analysis. Electricity by the light water nuclear power plant, the hydrogen power plant and the geothermal power plant are better candidates from EPR analysis. Forecasting the world primly energy supply in 2050, it is said that the demand will be double of the demand in 2000 and the supply will not be able to satisfy the demand in 2050. We should save 30% of the demand and increase nuclear power plants 3.5 times more and recyclable energy like hydropower plants 3 times more. When the nuclear power plants are 3.5 times more then uranium peak will come and we will need breed uranium. I will analysis the EPR of FBR. Conclusion: A) the EPR of NPS in Japan is 17.4 and it is the best of all. B) Many countries will introduce new nuclear power plants rapidly may be 3.5 times in 2050. C) Uranium peak will happen around 2050. (author)

Amano, Osamu [2-11-1, Iwado Kita, Komae-shi, Tokyo 201-8511 (Japan)



Climatic significance of isotope ratios  

Microsoft Academic Search

The hydrogen and oxygen isotope ratios of water, which can be measured by Isotope Ratio Mass Spectrometry (IRMS), exhibit climatic dependencies and are commonly exploited in hydrogeology. More generally, the overall carbon or hydrogen isotope ratios of plant organic matter, and in particular of tree-ring cellulose, have been frequently used for climatic reconstruction. However, since many physicochemical and biochemical fractionation

Gérard J. Martin; Maryvonne L. Martin



Poisson's ratio and crustal seismology  

Microsoft Academic Search

New measurements of compressional and shear wave velocities to hydrostatic pressures of 1 GPa are summarized for 678 rocks. Emphasis was placed on obtaining high-accuracy velocity measurements, which are shown to be critical in calculating Poisson's ratios from velocities. The rocks have been divided into 29 major groups for which velocities, velocity ratios, and Poisson's ratios are presented at several

Nikolas I. Christensen



Central Tendency () Central Tendency 1 / 11  

E-print Network

Central Tendency () Central Tendency 1 / 11 #12;Median is the middle score (50th percentile) Median are 4,5 Median = (1.3 + 1.4)/2 = 1.35. () Central Tendency 2 / 11 #12;Mean is the average score Given 5 (7 1) + (3 1) + (( 1) 1) + (2 1) + (( 6) 1)) = 6 + 2 2 + 1 7 = 0 () Central Tendency 3 / 11 #12;Mean

Busemeyer, Jerome R.


An urn model and the odds ratio-based design for clinical trials  

E-print Network

An urn model and the odds ratio-based design for clinical trials Gopal K. Basak , Atanu Biswas for using the odds ratio-based adaptive designs. Key words and phrases: adaptive designs, Central Limit Theorem, limiting allocation probability, odds ratio estimates, play-the-winner rule. AMS subject

Volkov, Stanislav


Video Resources Central Asia  

E-print Network

Video Resources Central Asia · Central Asia Country Overviews: · Kyrgyzstan: Crisis in Kyrgyzstan: Fuel, Contracts, and Revolution along the Afghan Supply Chain

Qian, Ning


Multiple trait model combining random regressions for daily feed intake with single measured performance traits of growing pigs  

Microsoft Academic Search

A random regression model for daily feed intake and a conventional multiple trait animal model for the four traits average daily gain on test (ADG), feed conversion ratio (FCR), carcass lean content and meat quality index were combined to analyse data from 1 449 castrated male Large White pigs performance tested in two French central testing stations in 1997. Group

Urs Schnyder; Andreas Hofer; Florence Labroue; Niklaus Künzi



High ratio recirculating gas compressor  


A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor.

Weinbrecht, John F. (601 Oakwood Pl., NE., Albuquerque, NM 87123)



High ratio recirculating gas compressor  


A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor. 10 figs.

Weinbrecht, J.F.



Central Tendency and Variability  

NSDL National Science Digital Library

This chapter presents two important interrelated topics in statistics: central tendency and variability. Measures of central tendency show how similar the data points in a set of data are, while measures of variability show how much the

Christmann, Edwin P.; Badgett, John L.



Axioms for Centrality  

E-print Network

Given a social network, which of its nodes are more central? This question has been asked many times in sociology, psychology and computer science, and a whole plethora of centrality measures (a.k.a. centrality indices, or rankings) were proposed to account for the importance of the nodes of a network. In this paper, we try to provide a mathematically sound survey of the most important classic centrality measures known from the literature and propose an axiomatic approach to establish whether they are actually doing what they have been designed for. Our axioms suggest some simple, basic properties that a centrality measure should exhibit. Surprisingly, only a new simple measure based on distances, harmonic centrality, turns out to satisfy all axioms; essentially, harmonic centrality is a correction to Bavelas's classic closeness centrality designed to take unreachable nodes into account in a natural way. As a sanity check, we examine in turn each measure under the lens of information retrieval, leveraging sta...

Boldi, Paolo



Central Limit Theorem  

NSDL National Science Digital Library

This site from David Lane features a description of the central limit theorem used in statistics. Examples of frequency distributions are shown, and there is also a link to an interactive demonstration of the central limit theorem.

Lane, David M.


Central and peripheral demyelination  

PubMed Central

Several conditions cause damage to the inherently normal myelin of central nervous system, perepheral nervous system or both central and perepheral nervous system and hence termed as central demyelinating diseases, perepheral demyelinating diseases and combined central and perepheral demyelinating diseases respectively. Here we analysed and foccused on the etiology, prevalance, incidence and age of these demyelinating disorders. Clinical attention and various diagnostic tests are needed to adequately assess all these possibilities. PMID:24741263

Mehndiratta, Man Mohan; Gulati, Natasha Singh



Denuclearizing central Asia  

Microsoft Academic Search

This study deals with two interrelated issues: the withdrawal of Soviet nuclear weapons from Central Asia; and the regional nuclear?weapon?free zone (NWFZ) initiative. Central Asian countries succeeded in denuclearizing the region. The ex?Soviet nuclear weapons were withdrawn from Central Asia, and fissile material production for military purposes was stopped. The Central Asian states acceded to the Non?Proliferation Treaty (NPT) and

Alexander Sergounin



European Central Bank  

NSDL National Science Digital Library

Together with the national central banks of the European Union, the European Central Bank (ECB) collects statistical information and governs the European System of Central Banks (ESCB). Legal texts about the ECB, the ESCB, and the European Monetary Union (EMI) are provided in addition to press releases, speeches, euro area statistics and selected publications of the EMI (in eleven European languages).


Central Venous Catheter Access  

Microsoft Academic Search

Central venous access for the purpose of supplying parenteral nutrition to the pediatric age group requires a careful definition of the patient’s caloric need, estimated duration of therapy, and an assessment of available sites. Peripheral vein parenteral nutrition is limited by caloric density of the nutrient fluids, while peripherally inserted central catheters (PICC) offers a new technology for accessing central

Dai H Chung; Moritz M Ziegler




E-print Network

1 OPERATOR INTERACTION WITH CENTRALIZED VERSUS DECENTRALIZED UAV ARCHITECTURES Affiliation M research activity attempting to streamline Unmanned Aerial Vehicle (UAV) operations and reduce staffing in order to invert the current many-to-one ratio of operators to vehicles. Centralized multiple UAV

Cummings, Mary "Missy"


Origin of Lead in Eight Central European Peat Bogs Determined  

E-print Network

Research Origin of Lead in Eight Central European Peat Bogs Determined from Isotope Ratios. The Sphagnum-dominated bogs were located mainly in mountainous regions of the Czech Republic bordering that environmental lead in Central Europe had been largely affected by human activity (smelting) even before

Wieder, R. Kelman


Point Estimation: Odds Ratios, Hazard Ratios, Risk Differences, Precision  

NSDL National Science Digital Library

This site provides a PowerPoint presentation, created by Dr. Elizabeth Garrett-Mayer of Johns Hopkins University, of a lesson and examples of point estimation, odds ratios, hazard ratios, risk differences and precision. The presentations is quite thorough. The author attempts to define, provide examples of, and then show the application of almost every concept. The presentation follows a easily followed and logical order. Mathematical formulas are intertwined within the slides. If further research is necessary, the author has provided a list of references and cites them during the presentation.

Garrett-Mayer, Elizabeth



Inbreeding and parasite sex ratios.  

PubMed Central

The breeding system of parasitic protozoa affects the evolution of drug resistance and virulence, and is relevant to disease diagnosis and the development of chemo- and immunotherapy. A major group of protozoan parasites, the phylum Apicomplexa, that includes the aetiological agents of malaria, toxoplasmosis and coccidiosis, all have dimorphic sexual stages. The sex ratio (proportion of males produced by parasites) is predicted to depend upon the inbreeding rate, and it has been suggested that sex-ratio data offer a relatively cheap and easy method for indirectly estimating inbreeding rates. Here, we exploit a new theoretical machinery to show that there are generally valid relationships between f, Wright's coefficient of inbreeding, and sex ratio, z(*), the generality being with respect to population structure. To focus the discussion, we concentrate on malaria and show that the previously derived result, f = 1 - 2z(*), does not depend on the artificial assumptions about population structure that were previously made. Not only does this justify the use of sex ratio as an indirect measure of f, but also we argue that it may actually be preferable to measure f by measuring sex ratios, rather than by measuring departures from Hardy-Weinberg genotypic proportions both in malaria and parasites more generally. PMID:11934369

Nee, Sean; West, Stuart A; Read, Andrew F



Discovering Phi: The Golden Ratio  

NSDL National Science Digital Library

Students discover the mathematical constant phi, the golden ratio, through hands-on activities. They measure dimensions of "natural objects"—a star, a nautilus shell and human hand bones—and calculate ratios of the measured values, which are close to phi. Then students learn a basic definition of a mathematical sequence, specifically the Fibonacci sequence. By taking ratios of successive terms of the sequence, they find numbers close to phi. They solve a squares puzzle that creates an approximate Fibonacci spiral. Finally, the instructor demonstrates the rule of the Fibonacci sequence via a LEGO® MINDSTORMS® NXT robot equipped with a pen. The robot (already created as part of the companion activity, The Fibonacci Sequence & Robots) draws a Fibonacci spiral that is similar to the nautilus shape.

AMPS GK-12 Program,


Measurement of tau branching ratios  

Microsoft Academic Search

We have measured the branching ratios for several tau decay modes. We use e+e--->tau+tau- events accumulated with the TPC\\/Two-Gamma facility at the SLAC e+e- storage ring PEP. The data correspond to an integrated luminosity of 77 pb-1 at a center-of-mass energy of 29 GeV. The one- and three-charged-particle inclusive branching ratios of the tau decay are measured to be B1=(84.7+\\/-1.0)%

H. Aihara; M. Alston-Garnjost; R. E. Avery; J. A. Bakken; A. Barbaro-Galtieri; A. R. Barker; A. V. Barnes; B. A. Barnett; D. A. Bauer; H.-U. Bengtsson; D. L. Bintinger; G. J. Bobbink; T. S. Bolognese; A. D. Bross; C. D. Buchanan; A. Buijs; D. O. Caldwell; C.-Y. Chien; A. R. Clark; G. D. Cowan; D. A. Crane; O. I. Dahl; K. A. Derby; J. J. Eastman; T. K. Edberg; P. H. Eberhard; A. M. Eisner; R. Enomoto; F. C. Erné; T. Fujii; J. W. Gary; W. Gorn; J. M. Hauptman; W. Hofmann; J. E. Huth; J. Hylen; T. Kamae; H. S. Kaye; K. H. Kees; R. W. Kenney; L. T. Kerth; Winston Ko; R. I. Koda; R. R. Kofler; K. K. Kwong; R. L. Lander; W. G. Langeveld; J. G. Layter; F. L. Linde; C. S. Lindsey; S. C. Loken; A. Lu; X.-Q. Lu; G. R. Lynch; L. Madansky; R. J. Madaras; K. Maeshima; B. D. Magnuson; J. N. Marx; G. E. Masek; L. G. Mathis; J. A. Matthews; S. J. Maxfield; S. O. Melnikoff; E. S. Miller; W. Moses; R. R. McNeil; P. Nemethy; D. R. Nygren; P. J. Oddone; H. P. Paar; D. A. Park; S. K. Park; D. E. Pellett; A. Pevsner; M. Pripstein; M. T. Ronan; R. R. Ross; F. R. Rouse; K. A. Schwitkis; J. C. Sens; G. Shapiro; M. D. Shapiro; B. C. Shen; W. E. Slater; J. R. Smith; J. S. Steinman; M. L. Stevenson; D. H. Stork; M. G. Strauss; M. K. Sullivan; T. Takahashi; J. R. Thompson; N. Toge; S. Toutounchi; R. van Tyen; B. van Uitert; G. J. Vandalen; R. F. van Daalen Wetters; W. Vernon; W. Wagner; E. M. Wang; Y. X. Wang; M. R. Wayne; W. A. Wenzel; J. T. White; M. C. Williams; Z. R. Wolf; H. Yamamoto; S. J. Yellin; C. Zeitlin; W.-M. Zhang



Surface to Volume Ratio Activity  

NSDL National Science Digital Library

By the National Nanotechnology Infrastructure Network, this two-part laboratory activity was designed to complement any chemistry unit on catalysts to "help students understand how nanoparticles may be more effective catalysts by investigating how the surface area-to-volume ratio of a substance is affected as its shape changes." On this site, educators can find both the teacher and student instructions for preparing and presenting the laboratory with objectives, time periods, materials, procedures, example answers, and much more. It is a ready-to-use lesson to help students understand catalysts and surface to volume ratio at molecular and atomic levels.


Brillouin Scattering in Water: The Landau—Placzek Ratio  

Microsoft Academic Search

An experimental study of the ratio of intensities of the central line, in the molecular scattering of light, to the Brillouin components has been made in water over a temperature range from 0° to 50°C. A 75-mW He&sngbnd;Ne gas laser was used as a light source and the scattered radiation was analyzed by a pressure-scanned Fabry—Perot interferometer in conjunction with

C. Leonard O'Connor; Joseph P. Schlupf



A Ratio Explanation for Evolution.  

ERIC Educational Resources Information Center

Describes hands-on physical anthropology activities for teaching students about evolution. Using evidence found in hominid skulls, students conduct investigations that involve calculating ratios. Eight full-page photographs of skulls from the program Stones and Bones are included. (PR)

Riss, Pam Helfers



Empirical Likelihood Ratio Confidence Regions  

Microsoft Academic Search

An empirical likelihood ratio function is defined and used to obtain confidence regions for vector valued statistical functionals. The result is a nonparametric version of Wilks' theorem and a multivariate generalization of work by Owen. Cornish-Fisher expansions show that the empirical likelihood intervals for a one dimensional mean are less adversely affected by skewness than are those based on Student's

Art Owen



Envera Variable Compression Ratio Engine  

Microsoft Academic Search

Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy

Charles Mendler



Random Cross Ratios Kalle strm  

E-print Network

systems. A short background into invariant based recognition is given. The use of the result ratio, e.g. in autonomous vehicle navigation, object recognition and reconstruction from images. 1 have become increasingly popular in Computer Vision, e.g. in reconstruction and recognition algorithms

Lunds Universitet


Optimal gear ratios of drives  

Microsoft Academic Search

One of the most complex problems in the design of practically any mechanism or machine is to select the gear ratio of an electric drive, on the basis of scientific, engineering, and economic principles. There is an extensive literature on this subject, dating mainly to the period from the 1940s to the 1960s. In current economic conditions, however, this problem

B. N. Polyakov



Blowing Ratio Effects on Film Cooling Effectiveness  

E-print Network

coolant tends to attach closer to the blade surface compared to the light density ratio coolant at the same blowing ratio. 10 Sinha et al. [18] studied similarly on various density ratio coolants under different blowing ratio. For a constant density ratio...

Liu, Kuo-Chun



Optomechanical Raman-Ratio Thermometry  

E-print Network

The temperature dependence of the asymmetry between Stokes and anti-Stokes Raman scattering can be exploited for self-calibrating, optically-based thermometry. In the context of cavity optomechanics, we observe the cavity-enhanced scattering of light interacting with the standing-wave drumhead modes of a silicon nitride membrane mechanical resonator. The ratio of the amplitude of Stokes to anti-Stokes scattered light is used to measure temperatures of optically-cooled mechanical modes down to the level of a few vibrational quanta. We demonstrate that the Raman-ratio technique is able to measure the physical temperature of our device over a range extending from cryogenic temperatures to within an order of magnitude of room temperature.

T. P. Purdy; P. -L. Yu; N. S. Kampel; R. W. Peterson; K. Cicak; R. W. Simmonds; C. A. Regal



GUT Scale Fermion Mass Ratios  

NASA Astrophysics Data System (ADS)

We present a series of recent works related to group theoretical factors from GUT symmetry breaking which lead to predictions for the ratios of quark and lepton Yukawa couplings at the unification scale. New predictions for the GUT scale ratios y?/ys, y?/yb and yt/yb in particular are shown and compared to experimental data. For this comparison it is important to include possibly large supersymmetric threshold corrections. Due to this reason the structure of the fermion masses at the GUT scale depends on TeV scale physics and makes GUT scale physics testable at the LHC. We also discuss how this new predictions might lead to predictions for mixing angles by discussing the example of the recently measured last missing leptonic mixing angle ?13 making this new class of GUT models also testable in neutrino experiments.

Spinrath, Martin



Models of Ratio Schedule Performance  

PubMed Central

Predictions of P. R. Killeen's (1994) mathematical principles of reinforcement were tested for responding on ratio reinforcement schedules. The type of response key, the number of sessions per condition, and first vs. second half of a session had negligible effects on responding. Longer reinforcer durations and larger grain types engeridered more responding, affecting primarily the parameter a (specific activation). Key pecking was faster than treadle pressing, affecting primarily the parameter ? (response time). Longer intertrial intervals led to higher overall response rates and shorter postreinforcement pauses and higher running rates, and ruled out some competing explanations. The treadle data required a distinction between the energetic requirements and rate-limiting properties of extended responses. The theory was extended to predict pause durations and run rates on ratio schedules. PMID:9206029

Bizo, Lewis A.; Killeen, Peter R.



Oxygen isotope ratio studies in the Galactic center region  

NASA Astrophysics Data System (ADS)

Using the Delingha 13.7 m telescope with a 9-beam SIS superconducting receiver installed, we carried out mapping of C18O and C17O J = (1 - 0) toward molecular clouds in the central molecular zone (CMZ) and in the halo of our galaxy. From the integrated intensity ratio of C18O to C17O, the isotope ratio 18O/17O ratio can be estimated, which is considered to be one of the most useful tracers of nuclear processing and metal enrichment. Here preliminary results are presented toward Sgr A, Sgr B2, Sgr C, Sgr D, and the 1.°3 complex in the CMZ and M+5.3-0.3 in the halo.

Zhang, JiangShui; Sun, Lulu; Qiu, Jianjie; Lu, Dengrong; Wang, Min



Geometry of operator cross ratio  

NASA Astrophysics Data System (ADS)

The operator cross ratio, which is meaningful, in particular, for the infinite-dimensional Sato Grassmannian is defined and investigated. Its homological interpretation is presented. A matrix and operator analogue of the Schwartzian differential operator is introduced and its relation to linear Hamiltonian systems and Riccati's equation is established. The aim of these constructions is application to the KP-hierarchy (the Kadomtsev-Petviashvili hierarchy).

Zelikin, M. I.



Rational Industrial Water Reuse Ratios  

NASA Astrophysics Data System (ADS)

This work begins by defining rational water use, and then discusses important factors that most strongly influence it. A general model is then developed to enable factories to quantify the ratio of rational industrial water reuse based on the least cost method. The model is established to minimize the cost of water with reference to gross water use and three subsystems - the intake, reuse, and discharge of industrial water. Discharge cost is determined using data from a 1997 survey of 38 factories, and reuse costs are ranked and expressed by a step function. The model is verified using data from a typical semiconductor factory in northern Taiwan's Hsinchu Science Based Industrial Park, whose effective rational water reuse ratio is about 38 percent. A sensitivity analysis shows that improving water reuse technology is the most important factor in determining the rational water reuse ratio, and the price of water is the second most important. When water costs over NT30 (New Taiwan Dollar, US1 = NT$34) per cubic meter, increasing reuse becomes significant. The model provides a step towards the scientific management of industrial water.

Liaw, Chao-Hsien; Chen, Liang-Ching



North America Europe Central &  

E-print Network

1 North America Western Europe Central & Eastern Europe Latin America & Caribbean Middle East & Central Asia Asia Pacific Africa Population (100 millions) 0 5 10 15 20 25 30 35 North America Western Per capita consumption Population (100 millions) 0 5 10 15 20 25 30 35 North America Western Europe

Johnson, Matthew


Wetlands of Central America  

Microsoft Academic Search

The wetlands of seven Central American countries – Belize, Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica, and Panamá – are reviewed. The region's wetlands are classified into five systems: marine, estuarine, riverine, lacustrine, and palustrine. At a minimum, wetlands cover ˜40,000 km2 (˜8%) of the land area of Central America. These wetlands support high levels of biological diversity, especially of

Aaron M. Ellison



Central Banking Resource Center  

NSDL National Science Digital Library

Central Banks of the World is a pointers page to central banks and central bank information for over 45 countries, as well as multilateral financial institutions, research and training establishments, and conference information. To show how little is generally known about the history of central banking in the United States, this site includes an email message sent to the webmaster of the First Bank of the United States, promoting a certain software company's web interactivity applications. Of course, since the First Bank of the United States was closed in 1811, its web site is primarily historical. The Central Banks site lists over 30 Internet directories and pointers pages that list the First Bank of the United States as a functioning financial institution. To help remedy this situation, the site includes a pointer to a brief history of banking in the US.



Envera Variable Compression Ratio Engine  

SciTech Connect

Aggressive engine downsizing, variable compression ratio and use of the Atkinson cycle are being combined to improve fuel economy by up to 40 percent relative to port fuel injected gasoline engines, while maintaining full engine power. Approach Engine downsizing is viewed by US and foreign automobile manufacturers as one of the best options for improving fuel economy. While this strategy has already demonstrated a degree of success, downsizing and fuel economy gains are currently limited. With new variable compression ratio technology however, the degree of engine downsizing and fuel economy improvement can be greatly increased. A small variable compression ratio (VCR) engine has the potential to return significantly higher vehicle fuel economy while also providing high power. Affordability and potential for near term commercialization are key attributes of the Envera VCR engine. VCR Technology To meet torque and power requirements, a smaller engine needs to do more work per stroke. This is typically accomplished by boosting the incoming charge with either a turbo or supercharger so that more energy is present in the cylinder per stroke to do the work. With current production engines the degree of engine boosting (which correlates to downsizing) is limited by detonation (combustion knock) at high boost levels. Additionally, the turbo or supercharger needs to be responsive and efficient while providing the needed boost. VCR technology eliminates the limitation of engine knock at high load levels by reducing compression ratio to {approx}9:1 (or whatever level is appropriate) when high boost pressures are needed. By reducing the compression ratio during high load demand periods there is increased volume in the cylinder at top dead center (TDC) which allows more charge (or energy) to be present in the cylinder without increasing the peak pressure. Cylinder pressure is thus kept below the level at which the engine would begin to knock. When loads on the engine are low the compression ratio can be raised (to as much as 18:1) providing high engine efficiency. It is important to recognize that for a well designed VCR engine cylinder pressure does not need to be higher than found in current production turbocharged engines. As such, there is no need for a stronger crankcase, bearings and other load bearing parts within the VCR engine. The Envera VCR mechanism uses an eccentric carrier approach to adjust engine compression ratio. The crankshaft main bearings are mounted in this eccentric carrier or 'crankshaft cradle' and pivoting the eccentric carrier 30 degrees adjusts compression ratio from 9:1 to 18:1. The eccentric carrier is made up of a casting that provides rigid support for the main bearings, and removable upper bearing caps. Oil feed to the main bearings transits through the bearing cap fastener sockets. The eccentric carrier design was chosen for its low cost and rigid support of the main bearings. A control shaft and connecting links are used to pivot the eccentric carrier. The control shaft mechanism features compression ratio lock-up at minimum and maximum compression ratio settings. The control shaft method of pivoting the eccentric carrier was selected due to its lock-up capability. The control shaft can be rotated by a hydraulic actuator or an electric motor. The engine shown in Figures 3 and 4 has a hydraulic actuator that was developed under the current program. In-line 4-cylinder engines are significantly less expensive than V engines because an entire cylinder head can be eliminated. The cost savings from eliminating cylinders and an entire cylinder head will notably offset the added cost of the VCR and supercharging. Replacing V6 and V8 engines with in-line VCR 4-cylinder engines will provide high fuel economy at low cost. Numerous enabling technologies exist which have the potential to increase engine efficiency. The greatest efficiency gains are realized when the right combination of advanced and new technologies are packaged together to provide the greatest gains at the least cost. Aggressive engine downsiz

Charles Mendler



Detection Strategies for Extreme Mass Ratio Inspirals  

E-print Network

The capture of compact stellar remnants by galactic black holes provides a unique laboratory for exploring the near horizon geometry of the Kerr spacetime, or possible departures from general relativity if the central cores prove not to be black holes. The gravitational radiation produced by these Extreme Mass Ratio Inspirals (EMRIs) encodes a detailed map of the black hole geometry, and the detection and characterization of these signals is a major scientific goal for the LISA mission. The waveforms produced are very complex, and the signals need to be coherently tracked for hundreds to thousands of cycles to produce a detection, making EMRI signals one of the most challenging data analysis problems in all of gravitational wave astronomy. Estimates for the number of templates required to perform an exhaustive grid-based matched-filter search for these signals are astronomically large, and far out of reach of current computational resources. Here I describe an alternative approach that employs a hybrid between Genetic Algorithms and Markov Chain Monte Carlo techniques, along with several time saving techniques for computing the likelihood function. This approach has proven effective at the blind extraction of relatively weak EMRI signals from simulated LISA data sets.

N. J. Cornish



Adaptive focusing - The likelihood ratio  

NASA Astrophysics Data System (ADS)

The problem of detecting a certain non-Gaussian random acoustic signal field in a spatially white Gaussian noise field is solved within the formalism of classical detection theory. Two solutions of the problem are compared: the maximum-likelihood or adaptive-focusing receiver and the Neyman-Pearson or adaptive focusing optimal (AFO) receiver. Based on two criteria for comparison, it is found that the two receivers differ only slightly in performance, with the AFO, of course, being the better. One of the criteria is based on the signal deflection ratio, and the other is the receiver operating characteristic curve. The comparisons are done for a Monte Carlo simulation.

Labianca, F. M.; Lloyd, S. P.



North Central Texas Council of Governments North Central Texas  

E-print Network

North Central Texas Council of Governments North Central Texas Thinking Ahead Donna Coggeshall North Central Texas Council of Governments #12;North Central Texas Council of Governments Thinking Ahead are for the 12-county MPA #12;North Central Texas Council of Governments Thinking Ahead Development Form #12

Texas at Arlington, University of


Precipitation chemistry in central Amazonia  

NASA Technical Reports Server (NTRS)

Rain samples from three sites in central Amazonia were collected over a period of 6 weeks during the 1987 wet season and analyzed for ionic species and dissolved organic carbon. A continuous record of precipitation chemistry and amount was obtained at two of these sites, which were free from local or regional pollution, for a time period of over 1 month. The volume-weighted mean concentrations of most species were found to be about a factor of 5 lower during the wet season compared with previous results from the dry season. Only sodium, potassium, and chloride showed similar concentrations in both seasons. When the seasonal difference in rainfall amount is taken into consideration, the deposition fluxes are only slightly lower for most species during the wet season than during the dry season, again with the exception of chloride, potassium, and sodium. Sodium and chloride are present in the same ratio as in sea salt; rapid advection of air masses of marine origin to the central Amazon Basin during the wet season may be responsible for the observed higher deposition flux of these species. Statistical analysis suggests that sulfate is, to a large extent, of marine (sea salt and biogenic) origin, but that long-range transport of combustion-derived aerosols also makes a significant contribution to sulfate and nitrate levels in Amazonian rain. Organic acid concentrations in rain were responsible for a large fraction of the observed precipitation acidity; their concentration was strongly influenced by gas/liquid interactions.

Andreae, M. O.; Talbot, R. W.; Berresheim, H.; Beecher, K. M.



High-aspect-ratio wings  

NASA Technical Reports Server (NTRS)

High-aspect-ratio aircraft include most transport aircraft such as commercial and military transports, business aircraft, and cargo aircraft. Generally, these types of aircraft are designed to cruise over a narrow range of lift coefficients and Mach numbers in the performance of their mission. Emphasis is therefore placed on the cruise performance of transport aircraft and every effort is made to obtain accurate wind-tunnel data to use as a basis for prediction of full-scale cruise performance. However, off-cruise performance is also important and methods were developed for extrapolating wind-tunnel data on buffet and flutter at transonic speed. Transport-type aircraft were tested extensively in various wind tunnels around the world and many different test techniques were developed to simulate higher Reynolds numbers. Methods developed for one tunnel may not be applicable to another tunnel because of differences in size, Reynolds number capability, running time, and test objectives. Many of the methods of boundary-layer control developed in two-dimensional airfoil testing can be applied in tests of transport configurations, but sometimes the three-dimensional flow fields that develop on tranpsort aircraft can make application of the two-dimensional methods difficult or impossible. The discussion is intended to be a representative, but not exhaustive, survey of the various methods of high Reynolds number simulation in the testing of high-aspect-ratio aircraft.

Peterson, John B., Jr.




NSDL National Science Digital Library

MoneyCentral is a new personal finance site by Microsoft now in public beta test. An expanded and more user-friendly form of MSN's Money Insider (discussed in the October 23, 1997 Scout Report for Business & Economics), MoneyCentral encompasses a wide variety of guides and tools on everything from Family Financing to Real Estate, Taxes and Investing. Visitors may view the full range of MoneyCentral topics from a clearly-arranged and clickable site map among other helpful links.


Central Force JS Model  

NSDL National Science Digital Library

The Central Force JavaScript Model computes the trajectory of a particle acted on by a central force.  The model reads uses a JavaScript mathematical expression parser to read the force and a adaptive step Runge-Kutta 5(4) algorithm to compute the trajectory.  This model is designed to test the speed of the JS parser and the accuracy of the EJS JavaScript ODE solver. The Central Force JS Model was developed using the Easy Java Simulations (EJS) version 5. It is distributed as a ready-to-run html page and requires only a browser with JavaScript support.

Christian, Wolfgang



Central serous choroidopathy  


... the disease lasts longer, may be helped by laser treatment or photodynamic therapy to seal the leak ... small number of patients will have complications of laser treatment that impair central vision. That is why ...


Central ballast tanker design  

SciTech Connect

The purpose of this paper is to present the CENTRAL BALLAST TANKER Design. This design is intended to reduce the volume of oil spilled from tankers by giving the crew a tanker properly designed and equipped to allow large quantities of oil from ruptured tank(s) to flow safely to a fully-inerted central ballast tank. In addition to reducing the volume of oil spilled, the design also addresses many of the shortcomings of the DOUBLE HULL DESIGN which are increasingly becoming a concern. The following is a brief review of the development of the CENTRAL BALLAST TANKER. The simple operational features, stability, low cost and ease of maintenance of the single hull tanker were important and can be retained with the CENTRAL BALLAST DESIGN.




Central Cord Syndrome  


... to those over the age of 50. What research is being done? Our understanding of central cord syndrome has increased greatly in recent decades as a result of research funded conducted by the National Institute of Neurological ...


Central sleep apnea  


... in someone who has a problem with the brainstem, which controls breathing. Conditions that can cause or ... central sleep apnea include: Problems that affect the brainstem (the brainstem controls breathing) including brain infection, stroke, ...


Exploring Central Tendency  

NSDL National Science Digital Library

This lesson is designed for 6th grade students. Student will work in small groups to apply central tendency to a real world scenario to finally answer the age old question of "when will I ever use this."

Friske, Monica



Probability: Central limit theorem  

NSDL National Science Digital Library

After heuristically deriving Stirling's approximation in the first video segment, we outline a simple example of the central limit theorem for the case of the binomial distribution. In the final segment, we explain how the central limit theorem is used to suggest that physical experiments are characterized by normally-distributed (Gaussian) fluctuations while fluctuations in biological experiments are said to fill out log-normal distributions.



A Centrality Detector Concept  

E-print Network

The nucleus-nucleus impact parameter and collision geometry of a heavy ion collision are typically characterized by assigning a collision "centrality". In all present heavy ion experiments centrality is measured indirectly, by detecting the number of particles or the energy of the particles produced in the interactions, typically at high rapidity. Centrality parameters are associated to the measured detector response using the Glauber model. This approach suffers from systematic uncertainties related to the assumptions about the particle production mechanism and limitations of the Glauber model. In the collider based experiments there is a unique possibility to measure centrality parameters by registering spectator fragments remaining from the collision. This approach does not require model assumptions and relies on the fact that spectators and participants are related via the total number of nucleons in the colliding species. This article describes the concept of the centrality detector for heavy ion experiment, which measures the total mass number of all fragments by measuring their deflection in the magnetic field of the collider elements.

Sourav Tarafdar; Zvi Citron; Alexander Milov



A centrality detector concept  

NASA Astrophysics Data System (ADS)

The nucleus-nucleus impact parameter and collision geometry of a heavy ion collision are typically characterized by assigning a collision "centrality". In all present heavy ion experiments centrality is measured indirectly, by detecting the number of particles or the energy of the particles produced in the interactions, typically at high rapidity. Centrality parameters are associated to the measured detector response using the Glauber model. This approach suffers from systematic uncertainties related to the assumptions about the particle production mechanism and limitations of the Glauber model. In the collider based experiments there is a unique possibility to measure centrality parameters by registering spectator fragments remaining from the collision. This approach does not require model assumptions and relies on the fact that spectators and participants are related via the total number of nucleons in the colliding species. This paper describes the concept of a centrality detector for heavy ion experiment, which measures the total mass number of all fragments by measuring their deflection in the magnetic field of the collider elements.

Tarafdar, Sourav; Citron, Zvi; Milov, Alexander



Occultation determination of Neptune's oblateness and stratospheric methane mixing ratio  

NASA Technical Reports Server (NTRS)

The occultation of a star by Neptune on August 20, 1985 was observed at 2.2 micron wavelength with telescopes at the European Southern Observatory (ESO) and the Cerro Tololo Inter-American Observatory (CTIO). The detection of a 'central flash' midway between immersion and emersion has allowed the determination of Neptune's oblateness and the atmospheric extinction at 2.2 microns, which is related to the stratospheric methane mixing ratio. An oblateness of (2.08 +0.19 or -0.18) x 10 to the 2nd is found and, assuming a stratospheric temperature of 120 K, a value of 0.6 percent is inferred (with an uncertainty of a factor of 10) for the methane mixing ratio (CH4/H2) at 0.3 mbar. The latter value may indicate supersaturation of methane in Neptune's stratosphere.

Lellouch, E.; Hubbard, W. B.; Sicardy, B.; Vilas, F.; Bouchet, P.



Video Lab -NOAA Central Library NOAA Central Library  

E-print Network

2014 Video Lab - NOAA Central Library NOAA Central Library 1315 East West Highway, SSMC3, 2nd Floor Silver Spring, MD 20910 #12;NOAA Central Library Video Lab The NOAA Central Library Video Lab is available to all NOAA scientists for their business related media work, including digital


Influence of neutron-skin thickness on $?^{-}/?^{+}$ ratio in Pb+Pb collisions  

E-print Network

Within an isospin- and momentum-dependent transport model IBUU11 using as an input nucleon density profiles from Hartree-Fock calculations based on a modified Skyrme-like (MSL) model, we study the influence of the uncertainty of the neutron skin thickness on the $\\pi^{-}/\\pi^{+}$ ratio in both central and peripheral Pb+Pb collisions at beam energies of 400 MeV/nucleon and 1000 MeV/nucleon. Within the current experimental uncertainty range of neutron skin in $^{208}$Pb, while the neutron skin effect on the \\rpi ratio is negligible in central reactions at both energies, it increases gradually with increasing impact parameter and becomes comparable with or even larger than the symmetry energy effect in peripheral collisions especially at 400 MeV/nucleon. Moreover, we found that while the \\rpi ratio is larger with a softer \\esym in central collisions, above certain impact parameters depending on the size of the neutron skin, a stiffer \\esym can lead to a larger \\rpi ratio as most of the pions are produced at densities below the saturation density in these peripheral reactions. Thus, a clear impact parameter selection is important to extract reliable information about the \\esym at suprasaturation densities (size of neutron skin) from the $\\pi^-/\\pi^+$ ratio in central (peripheral) heavy-ion collisions.

Gao-Feng Wei; Bao-An Li; Jun Xu; Lie-Wen Chen



Imaging changes in the cytosolic ATP-to-ADP ratio  

PubMed Central

Adenosine triphosphate (ATP) is a central metabolite that plays fundamental roles as an energy transfer molecule, a phosphate donor, and a signaling molecule inside cells. The phosphoryl group transfer potential of ATP provides a thermodynamic driving force for many metabolic reactions, and phosphorylation of both small metabolites and large proteins can serve as a regulatory modification. In the process of phosphoryl transfer from ATP, the diphosphate ADP is produced, and as a result, the ATP-to-ADP ratio is an important physiological control parameter. The ATP-to-ADP ratio is directly proportional to cellular energy charge and phosphorylation potential. Furthermore, several ATP-dependent enzymes and signaling proteins are regulated by ADP, and their activation profiles are a function of the ATP-to-ADP ratio. Finally, regeneration of ATP from ADP can serve as an important readout of energy metabolism and mitochondrial function. We therefore developed a genetically-encoded fluorescent biosensor tuned to sense ATP-to-ADP ratios in the physiological range of healthy mammalian cells. Here we present a protocol for using this biosensor to visualize energy status using live-cell fluorescence microscopy. PMID:25416365

Tantama, Mathew; Yellen, Gary



Centralized Mouse Repositories  

PubMed Central

Because the mouse is used so widely for biomedical research and the number of mouse models being generated is increasing rapidly, centralized repositories are essential if the valuable mouse strains and models that have been developed are to be securely preserved and fully exploited. Ensuring the ongoing availability of these mouse strains preserves the investment made in creating and characterizing them and creates a global resource of enormous value. The establishment of centralized mouse repositories around the world for distributing and archiving these resources has provided critical access to and preservation of these strains. This article describes the common and specialized activities provided by major mouse repositories around the world. PMID:22945696

Donahue, Leah Rae; de Angelis, Martin Hrabe; Hagn, Michael; Franklin, Craig; Lloyd, K. C. Kent; Magnuson, Terry; McKerlie, Colin; Nakagata, Naomi; Obata, Yuichi; Read, Stuart; Wurst, Wolfgang; Hörlein, Andreas; Davisson, Muriel T.



Rare pediatric central neurocytomas.  


Central neurocytoma is extremely rare in pediatrics. In a single institute's record, it represents about 0.2% of brain tumors in children. The treatment of central neurocytoma in children is not different from that for adult patients. Surgical resection is the mainstay of treatment. After complete resection, the long-term prognosis is excellent. Adjuvant radiation therapy or radiosurgery may be applied to residual or recurrent tumors. However, the exact indication for each modality should be refined by accumulation of clinical data for this rare disease in children. PMID:25432189

Phi, Ji Hoon; Kim, Dong Gyu




Children’s Hospital Central California is excited to announce a new clinical opportunity due to the expansion of our Pediatric Psychology department. Children’s Hospital Central California is a 354 bed not-for-profit, state-of-the-art free standing Children’s Hospital. As a vital member of our Pediatric Psychology team the primary focus of this position will be on providing consultation-liaison services to our various medical inpatient units. There will also be opportunities for providing assessment and therapy services for our subspecialty clinics.


The Central Limit Theorem  

NSDL National Science Digital Library

The applets in this section of Statistical Java allow you to see how the Central Limit Theorem works. The main page gives the characteristics of five non-normal distributions (Bernoulli, Poisson, Exponential, U-shaped, and Uniform). Users then select one of the distributions and change the sample size to see how the distribution of the sample mean approaches normality. Users can also change the number of samples. To select between the different applets you can click on Statistical Theory, the Central Limit Theorem and then the Main Page. At the bottom of this page you can make your applet selection.

Anderson-Cook, C.; Dorai-Raj, S.; Robinson, T.




Microsoft Academic Search

Before the 1960s, introductory trigonometry was taught in Victorian schools using the ratio method, where trigonometric functions are defined as ratios of sides of right angled triangles. With the advent of \\

Margaret Kendal; Kaye Stacey


Variable mixture ratio performance through nitrogen augmentation  

NASA Technical Reports Server (NTRS)

High/variable mixture ratio O2/H2 candidate engine cycles are examined for earth-to-orbit vehicle application. Engine performance and power balance information are presented for the candidate cycles relative to chamber pressure, bulk density, and mixture ratio. Included in the cycle screening are concepts where a third fluid (liquid nitrogen) is used to achieve a variable mixture ratio over the trajectory from liftoff to earth orbit. The third fluid cycles offer a very low risk, fully reusable, low operation cost alternative to high/variable mixture ratio bipropellant cycles. Variable mixture ratio engines with extendible nozzle are slightly lower performing than a single mixture ratio engine (MR = 7:1) with extendible nozzle. Dual expander engines (MR = 7:1) have slightly better performance than the single mixture ratio engine. Dual fuel dual expander engines offer a 16 percent improvement over the single mixture ratio engine.

Beichel, R.; Obrien, C. J.; Bair, E. K.



Density Ratio Examples Semiparametric Statistical Formulation  

E-print Network

UMinformal Density Ratio Examples Semiparametric Statistical Formulation Combined semiparametric density estimators Semiparametric regression Application to Testicular Germ Cell Cancer Semiparametric Density Ratio Examples Semiparametric Statistical Formulation Combined semiparametric density estimators

Johnson, Raymond L.


Computation of Cold-Start Miss Ratios  

Microsoft Academic Search

Cold-start miss ratios are miss ratios that are measured with an initially empty first-level store. The values obtained depend on C, the first-level storage capacity, and on T, the number of references. These miss ratios, measured for various values of T, are useful in evaluating the effect of task switching on cache miss ratios when the cache capacity is C.

Malcolm C. Easton



Learning About Ratios: A Sandwich Study  

NSDL National Science Digital Library

This lesson introduces students to the concept of ratio through a hands-on, delicious experiment. After an introductory activity where students identify the ratio of girls to boys in a group of 10 selected students, they create six different peanut butter and jelly sandwiches with different ingredient ratios to find which is the tastiest. Students then plan their own similar experiment using other concoctions which can be expressed in ratios.

Weinberg, Sheryl




E-print Network

POWER CENTRALIZED SEMIGROUPS PRIMOZ MORAVEC Abstract. A semigroup is said to be power centralized if for every pair of elements x and y there exists a power of x commuting with y. The structure of power centralized groups and semigroups is investigated. In particular, we characterize 0-simple power centralized


Spray Gun With Constant Mixing Ratio  

NASA Technical Reports Server (NTRS)

Conceptual mechanism mounted in handle of spray gun maintains constant ratio between volumetric flow rates in two channels leading to spray head. With mechanism, possible to keep flow ratio near 1:1 (or another desired ratio) over range of temperatures, orifice or channel sizes, or clogging conditions.

Simpson, William G.



Bidding ratios to predict highway project costs  

Microsoft Academic Search

Purpose – Ratios were constructed using bidding data for highway construction projects in Texas to study whether there are useful patterns in project bids that are indicators of the project completion cost. The use of the ratios to improve predictions of completed project cost was studied. Design\\/methodology\\/approach – Ratios were calculated relating the second lowest bid, mean bid, and maximum

Trefor P. Williams



A dynamic analysis of stock price ratios  

Microsoft Academic Search

Stock price ratios have long been used by finance practitioners as a relative value metric. A popular argument for this widespread use is that stock price ratios tend to revert to their long-run mean so that substantial deviations from historical averages could successfully be arbitraged away. In this work, we lay out the theoretical conditions for the ratio of stock

Antoine Giannetti; Ariel Viale



High aspect ratio wrinkles via substrate prestretch.  


A non-fractured, high aspect ratio wrinkled surface is successfully fabricated. Building upon recently developed models of the localization transition and the current knowledge of surface failures, the wrinkling mode is stabilized at high strain, doubling the accessible wrinkling aspect ratio to the currently reported value. This high aspect ratio surface provides significant promise for future wrinkle-based applications. PMID:24863587

Chen, Yu-Cheng; Crosby, Alfred J



Comparison of Body Mass Index, Waist Circumference, and Waist\\/Hip Ratio in Predicting Incident Diabetes: A Meta-Analysis  

Microsoft Academic Search

Body mass index, waist circumference, and waist\\/hip ratio have been shown to be associated with type 2 diabetes. From the clinical perspective, central obesity (approximated by waist circumference or waist\\/hip ratio) is known to generate diabetogenic substances and should therefore be more informative than general obesity (body mass index). Because of their high correlation, from the statistical perspective, body mass

Gabriela Vazquez; Sue Duval; David R. Jacobs; Karri Silventoinen



Waist to height ratio is correlated with height in US children and adolescents age 2-18y  

Technology Transfer Automated Retrieval System (TEKTRAN)

The waist-to-height ratio is an anthropometric measure of central adiposity that has emerged as a significant predictor of cardiovascular risk factors in children and adolescents. The simple waist-to-height ratio, however, retains residual correlation with height, which could cause the measure to o...


Ghrelin in Central Neurons  

PubMed Central

Ghrelin, an orexigenic peptide synthesized by endocrine cells of the gastric mucosa, is released in the bloodstream in response to a negative energetic status. Since discovery, the hypothalamus was identified as the main source of ghrelin in the CNS, and effects of the peptide have been mainly observed in this area of the brain. In recent years, an increasing number of studies have reported ghrelin synthesis and effects in specific populations of neurons also outside the hypothalamus. Thus, ghrelin activity has been described in midbrain, hindbrain, hippocampus, and spinal cord. The spectrum of functions and biological effects produced by the peptide on central neurons is remarkably wide and complex. It ranges from modulation of membrane excitability, to control of neurotransmitter release, neuronal gene expression, and neuronal survival and proliferation. There is not at present a general consensus concerning the source of ghrelin acting on central neurons. Whereas it is widely accepted that the hypothalamus represents the most important endogenous source of the hormone in CNS, the existence of extra-hypothalamic ghrelin-synthesizing neurons is still controversial. In addition, circulating ghrelin can theoretically be another natural ligand for central ghrelin receptors. This paper gives an overview on the distribution of ghrelin and its receptor across the CNS and critically analyses the data available so far as regarding the effects of ghrelin on central neurotransmission. PMID:19721816

Ferrini, F; Salio, C; Lossi, L; Merighi, A



Multicultural Central Asia.  

ERIC Educational Resources Information Center

This article addresses the multicultural aspect of Central Asia in response to the discussion on diversity in U.S. classrooms. Many areas of the world are more diverse than the U.S., and these areas experience successes and failures with many of the same issues the U.S. is currently struggling with. Comparing the U.S. diversity debate with similar…

Boyle, Eric D.


Central Serous Retinopathy Treatment  


... Your Eyes & the Sun Eye Health News Consumer Alerts What Is Central Serous Retinopathy? Tweet The retina is the light-sensitive tissue lining the back of the eye. It converts light rays into electrical impulses that travel through the optic nerve to our brain, where ...


Central Idaho Debris Flow  

USGS Multimedia Gallery

During August 2013, the Beaver Creek wildfire burned more than 114,000 acres in south-central Idaho. Shortly after the fire was contained, heavy rainfall triggered numerous debris flows, including this one in Badger Gulch. USGS hydrologists Dave Evetts (left) and Jake Jacobson examine the debris flo...


Central nervous system tuberculosis.  


Tuberculosis (TB) has shown a resurgence in nonendemic populations in recent years and accounts for 8 million deaths annually in the world. Central nervous system involvement is one of the most serious forms of this infection, acting as a prominent cause of morbidity and mortality in developing countries. The rising number of cases in developed countries is mostly attributed to factors such as the pandemic of acquired immunodeficiency syndrome and increased migration in a globalized world. Mycobacterium TB is responsible for almost all cases of tubercular infection in the central nervous system. It can manifest in a variety of forms as tuberculous meningitis, tuberculoma, and tubercular abscess. Spinal infection may result in spondylitis, arachnoiditis, and/or focal intramedullary tuberculomas. Timely diagnosis of central nervous system TB is paramount for the early institution of appropriate therapy, because delayed treatment is associated with severe morbidity and mortality. It is therefore important that physicians and radiologists understand the characteristic patterns, distribution, and imaging manifestations of TB in the central nervous system. Magnetic resonance imaging is considered the imaging modality of choice for the study of patients with suspected TB. Advanced imaging techniques including magnetic resonance perfusion and diffusion tensor imaging may be of value in the objective assessment of therapy and to guide the physician in the modulation of therapy in these patients. PMID:24887691

Torres, Carlos; Riascos, Roy; Figueroa, Ramon; Gupta, Rakesh K



Channeling the Central Dogma.  


How do neurons and networks achieve their characteristic electrical activity, regulate this activity homeostatically, and yet show population variability in expression? In this issue of Neuron, O'Leary et al. (2014) address some of these thorny questions in this theoretical analysis that starts with the Central Dogma. PMID:24853932

Calabrese, Ronald L



Bound central orbits  

NASA Astrophysics Data System (ADS)

The orbits in any central potential are described analytically and new expressions are derived for their periods and precession rates. A simple perturbation theory allows their delineation to any accuracy. Kepler's equation is generalized to such orbits and angle and action variables are given for them. A new property of orbits under inverse fifth power forces is found.

Lynden-Bell, D.



Central tendency pole assignment  

Microsoft Academic Search

In adaptive control, there is a range of possibilities between the two extremes of applying the Certainty Equivalence Principle, which can only hold asymptotically, and Dual Control, which is not a practical proposition for on-line schemes. Here it is proposed that adaptive controllers be designed using Measures of Central Tendency of the a posteriori probability function of the control signal

John B. Moore; Tom Ryall; Lige Xia



Measures of Central Tendency.  

ERIC Educational Resources Information Center

This self-instructional, job-oriented booklet on descriptive statistics for the health professions deals specifically with measures of central tendency (mean, median and mode). It is limited to those concepts and techniques most needed by health professionals working routinely with basic statistical data. (CK)

Health Services and Mental Health Administration (DHEW), Bethesda, MD.


A quarterly and Central  

E-print Network

A quarterly report on employment and office markets in Northern and Central New Jersey November, boosting consumer confidence, and easing inflation. However, if the housing slowdown changes into a full 2) connected by transportation systems and a fast- growing port. The state's highly educated labor


Shear Viscosity to Entropy Density Ratio in Six Derivative Gravity  

E-print Network

We calculate shear viscosity to entropy density ratio in presence of four derivative (with coefficient $\\alpha'$) and six derivative (with coefficient $\\alpha'^2$) terms in bulk action. In general, there can be three possible four derivative terms and ten possible six derivative terms in the Lagrangian. Among them two four derivative and eight six derivative terms are ambiguous, i.e., these terms can be removed from the action by suitable field redefinitions. Rest are unambiguous. According to the AdS/CFT correspondence all the unambiguous coefficients (coefficients of unambiguous terms) can be fixed in terms of field theory parameters. Therefore, any measurable quantities of boundary theory, for example shear viscosity to entropy density ratio, when calculated holographically can be expressed in terms of unambiguous coefficients in the bulk theory (or equivalently in terms of boundary parameters). We calculate $\\eta/s$ for generic six derivative gravity and find that apparently it depends on few ambiguous coefficients at order $\\alpha'^2$. We calculate six derivative corrections to central charges $a$ and $c$ and express $\\eta/s$ in terms of these central charges and unambiguous coefficients in the bulk theory.

Nabamita Banerjee; Suvankar Dutta



Neural correlates of the Pythagorean ratio rules.  


Millennia ago Pythagoras noted a simple but remarkably powerful rule for the aesthetics of tone combinations: pairs of tones--intervals--with simple ratios such as an octave (ratio 2 : 1) or a fifth (ratio 3 : 2) were pleasant sounding (consonant), whereas intervals with complex ratios such as the major seventh (ratio 243 : 128) were harsh (dissonant). These Pythagorean ratio rules are the building blocks of Western classical music; however, their neurophysiologic basis is not known. Using functional MRI we have found the neurophysiologic correlates of the ratio rules. In musicians, the inferior frontal gyrus, superior temporal gyrus, medial frontal gyrus, inferior parietal lobule and anterior cingulate respond with progressively more activation to perfect consonances, imperfect consonances and dissonances. In nonmusicians only the right inferior frontal gyrus follows this pattern. PMID:17885594

Foss, Alexander H; Altschuler, Eric L; James, Karin H



The Effect of Satellite Galaxies on Gravitational Lensing Flux Ratios  

E-print Network

Gravitational lenses with anomalous flux ratios are often cited as possible evidence for dark matter satellites predicted by simulations of hierarchical merging in cold dark matter cosmogonies. We show that the fraction of quads with anomalous flux ratios depends primarily on the total mass and spatial extent of the satellites, and the characteristic lengthscale R of their distribution. If R is 100 kpc, then for a moderately elliptical galaxy with a line-of-sight velocity dispersion of 250 km/s, a mass of 3 x 10^9 solar masses in highly-concentrated (Plummer model) satellites is needed for 20% of quadruplets to show anomalous flux ratios, rising to 1.25 x 10^10 solar masses for 50%. Several times these masses are required if the satellites have more extended Hernquist profiles. Compared to a typical elliptical, the flux ratios of quads formed by typical edge-on disc galaxies with maximum discs are significantly less susceptible to changes through substructure -- three times the mass in satellite galaxies is needed to affect 50% of the systems. In many of the lens systems with anomalous flux ratios, there is evidence for visible satellites (e.g., B2045+265 or MG0414+0534). We show that optically identified substructure should not be preponderant among lens systems with anomalies. There are two possible resolutions of this difficulty. First, in some cases, visible substructure may be projected within or close to the Einstein radius and wrongly ascribed as the culprit, whereas dark matter substructure is causing the flux anomaly. Second, bright satellites, in which baryon cooling and condensation has taken place, may have higher central densities than dark satellites, rendering them more efficient at causing flux anomalies.

E. M. Shin; N. W. Evans



Source Temperatures and Sizes in Central Collisions  

E-print Network

For midrapidity fragments from central 50-200 AMeV Au+Au collisions temperatures from double ratios of isotopic yields were compared with temperatures from particle unbound states. Temperatures from particle unbound states with T = 4-5 MeV show with increasing beam energy an increasing difference to temperatures from double ratios of isotopic yields, which increase from T = 5MeV to T = 12MeV. The lower temperatures extracted from particle unstable states can be explained by increasing cooling of the decaying system due to expansion. This expansion is driven by the radial flow, and freeze out of particle unstable states might depend on the dynamics of the expanding system. Source sizes from pp-correlation functions were found to be 9 to 11 fm.

C. Schwarz; ALADIN collaboration




Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. CENTRAL HEIGHT OF CENTRAL PAVILION IN EAST FACADE--INCLINED, FRONTAL Copy photograph of photogrammetric plate LC-HABS-FS13-B-1974-832L. - St. Mary's Seminary, 600 North Paca Street, Baltimore, Independent City, MD


Investment Club Central  

NSDL National Science Digital Library

Investment Club Central was developed by invest-o-rama! to promote investment clubs. At the site, visitors will find many useful articles on how to start an investment club, as well as a collection of investment club news stories. Other resources at the site include a list of online data sources, links to stock research, tutorials on selecting stocks for the club and a directory of investment clubs online.

Gerlach, Douglas.



Lesson Plan Central  

NSDL National Science Digital Library

Lesson Plan Central -- a free lesson plans, WebQuests, worksheets, student link and clipart Web site -- has a great collection of science specific links. Categorized by subject and grade level, the listed sites are are briefly described, and any new site is labeled as such. Links to just the new, cool, and clipart sites are also provided. This collection is a great way for kids and educators to find new teaching and learning aids.



Central Internet Database  

NSDL National Science Digital Library

The Department of Energy maintains the Central Internet Database Web site. Here users can generate and print reports containing nationwide data on radioactive waste, contaminated media, and spent nuclear fuel. Ready to read reports are also available including Actual and Projected Waste/Material Volumes, Waste/Material Characteristic Data (contaminants/isotopes/radioactivity), and Treatment, Storage and Disposal (TSD) Systems. The site currently contains fifty nine standard and fourteen ready to read reports


Central interstate LLRW Commission  

SciTech Connect

This paper presents the past and present actions of the Central Interstate LLRW Commission regarding the construction and operation of an approved LLRW disposal facility for the five-state Compact region which includes Arkansas, Louisiana, Kansas, Nebraska, and Oklahoma. The site selection process, license application, and legal actions brought about by the communities and states impacted by the recommended site location are thoroughly reviewed. The health and safety hazards associated with a LLRW disposal facility are also discussed.

Crump, G.



Central Limit Theorem  

NSDL National Science Digital Library

This website, created by Richard Lowry of Vassar College, illustrates the central limit theorem by allowing the user to increase the number of samples in increments of 100, 1,000, or 10,000. The sample size can be changed and these changes will then be reflected in the distribution. Overall, this is a great interactive resource for students wanting to engage more in their study of statistics.

Lowry, Richard



Estimation of subsurface structure using microtremor H\\/V spectral ratio in the Shimabara peninsula  

Microsoft Academic Search

The Shimabara peninsula in Kyushu island of Japan, located on the west edge of the Beppu Shimabara graben which crosses the center part in Kyushu from east to west. Seventy percent of the peninsula is covered with volcanic product of Unzen volcano. Using strong motion H\\/V spectral ratio, the Central Disaster Prevention Council (2008) pointed out that the long-period strong

N. Itoya; T. Matsushima



Anatomic crown width\\/length ratios of unworn and worn maxillary teeth in white subjects  

Microsoft Academic Search

STATEMENT OF PROBLEM: Dimensions of teeth have been available for a century. Some significant and clinically relevant aspects of dental esthetics, however, such as the crown width\\/length ratios, have not been presented in tooth morphology sources until recently. PURPOSE: The purpose of this study was to analyze the anatomic crowns of 4 tooth groups (central incisors, lateral incisors, canines, and

Pascal Magne; German O Gallucci; Urs C Belser



Using a Market Ratio Factor in Faculty Salary Equity Studies. Professional File Number 103, Spring 2007  

ERIC Educational Resources Information Center

This study used two multiple regression analyses to develop an explanatory model to determine which model might best explain faculty salaries. The central purpose of the study was to determine if using a single market ratio variable was a stronger predictor for faculty salaries than the use of dummy variables representing various disciplines.…

Luna, Andrew L.



Central respiratory chemoreception.  


By definition central respiratory chemoreceptors (CRCs) are cells that are sensitive to changes in brain PCO(2) or pH and contribute to the stimulation of breathing elicited by hypercapnia or metabolic acidosis. CO(2) most likely works by lowering pH. The pertinent proton receptors have not been identified and may be ion channels. CRCs are probably neurons but may also include acid-sensitive glia and vascular cells that communicate with neurons via paracrine mechanisms. Retrotrapezoid nucleus (RTN) neurons are the most completely characterized CRCs. Their high sensitivity to CO(2) in vivo presumably relies on their intrinsic acid sensitivity, excitatory inputs from the carotid bodies and brain regions such as raphe and hypothalamus, and facilitating influences from neighboring astrocytes. RTN neurons are necessary for the respiratory network to respond to CO(2) during the perinatal period and under anesthesia. In conscious adults, RTN neurons contribute to an unknown degree to the pH-dependent regulation of breathing rate, inspiratory, and expiratory activity. The abnormal prenatal development of RTN neurons probably contributes to the congenital central hypoventilation syndrome. Other CRCs presumably exist, but the supportive evidence is less complete. The proposed locations of these CRCs are the medullary raphe, the nucleus tractus solitarius, the ventrolateral medulla, the fastigial nucleus, and the hypothalamus. Several wake-promoting systems (serotonergic and catecholaminergic neurons, orexinergic neurons) are also putative CRCs. Their contribution to central respiratory chemoreception may be behavior dependent or vary according to the state of vigilance. PMID:20737591

Guyenet, Patrice G; Stornetta, Ruth L; Bayliss, Douglas A



Central respiratory chemoreception  

PubMed Central

Summary By definition central respiratory chemoreceptors (CRCs) are cells that are sensitive to changes in brain PCO2 or pH and contribute to the stimulation of breathing elicited by hypercapnia or metabolic acidosis. CO2 most likely works by lowering pH. The pertinent proton receptors have not been identified and may be ion channels. CRCs are probably neurons but may also include acid-sensitive glia and vascular cells that communicate with neurons via paracrine mechanisms. Retrotrapezoid nucleus (RTN) neurons are the most completely characterized CRCs. Their high sensitivity to CO2 in vivo presumably relies on their intrinsic acid-sensitivity, excitatory inputs from the carotid bodies and brain regions such as raphe and hypothalamus, and facilitating influences from neighboring astrocytes. RTN neurons are necessary for the respiratory network to respond to CO2 during the perinatal period and under anesthesia. In conscious adults, RTN neurons contribute to an unknown degree to the pH-dependent regulation of breathing rate, inspiratory and expiratory activity. The abnormal prenatal development of RTN neurons probably contributes to the congenital central hypoventilation syndrome. Other CRCs presumably exist but the supportive evidence is less complete. The proposed locations of these CRCs are the medullary raphe, the nucleus tractus solitarius, the ventrolateral medulla, the fastigial nucleus and the hypothalamus. Several wake-promoting systems (serotonergic and catecholaminergic neurons, orexinergic neurons) are also putative CRCs. Their contribution to central respiratory chemoreception may be behavior-dependent or vary according to the state of vigilance. PMID:20737591

Guyenet, Patrice G.; Stornetta, Ruth L.; Bayliss, Douglas A.



Eccentric crank variable compression ratio mechanism  


A variable compression ratio mechanism for an internal combustion engine that has an engine block and a crankshaft is disclosed. The variable compression ratio mechanism has a plurality of eccentric disks configured to support the crankshaft. Each of the plurality of eccentric disks has at least one cylindrical portion annularly surrounded by the engine block. The variable compression ratio mechanism also has at least one actuator configured to rotate the plurality of eccentric disks.

Lawrence, Keith Edward (Kobe, JP); Moser, William Elliott (Peoria, IL); Roozenboom, Stephan Donald (Washington, IL); Knox, Kevin Jay (Peoria, IL)



Separated Response Function Ratios in Exclusive, Forward ?± Electroproduction  

NASA Astrophysics Data System (ADS)

The study of exclusive ?± electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=?L?-/?L?+ is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=?T?-/?T?+ from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive ?± electroproduction on the deuteron at central Q2 values of 0.6, 1.0, 1.6 GeV2 at W =1.95 GeV, and Q2=2.45 GeV2 at W =2.22 GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.

Huber, G. M.; Blok, H. P.; Butuceanu, C.; Gaskell, D.; Horn, T.; Mack, D. J.; Abbott, D.; Aniol, K.; Anklin, H.; Armstrong, C.; Arrington, J.; Assamagan, K.; Avery, S.; Baker, O. K.; Barrett, B.; Beise, E. J.; Bochna, C.; Boeglin, W.; Brash, E. J.; Breuer, H.; Chang, C. C.; Chant, N.; Christy, M. E.; Dunne, J.; Eden, T.; Ent, R.; Fenker, H.; Gibson, E. F.; Gilman, R.; Gustafsson, K.; Hinton, W.; Holt, R. J.; Jackson, H.; Jin, S.; Jones, M. K.; Keppel, C. E.; Kim, P. H.; Kim, W.; King, P. M.; Klein, A.; Koltenuk, D.; Kovaltchouk, V.; Liang, M.; Liu, J.; Lolos, G. J.; Lung, A.; Margaziotis, D. J.; Markowitz, P.; Matsumura, A.; McKee, D.; Meekins, D.; Mitchell, J.; Miyoshi, T.; Mkrtchyan, H.; Mueller, B.; Niculescu, G.; Niculescu, I.; Okayasu, Y.; Pentchev, L.; Perdrisat, C.; Pitz, D.; Potterveld, D.; Punjabi, V.; Qin, L. M.; Reimer, P. E.; Reinhold, J.; Roche, J.; Roos, P. G.; Sarty, A.; Shin, I. K.; Smith, G. R.; Stepanyan, S.; Tang, L. G.; Tadevosyan, V.; Tvaskis, V.; van der Meer, R. L. J.; Vansyoc, K.; Van Westrum, D.; Vidakovic, S.; Volmer, J.; Vulcan, W.; Warren, G.; Wood, S. A.; Xu, C.; Yan, C.; Zhao, W.-X.; Zheng, X.; Zihlmann, B.; Jefferson Lab F? Collaboration



Separated response function ratios in exclusive, forward ?(±) electroproduction.  


The study of exclusive ?(±) electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=?L(?-)/?L(?+) is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=?T(?-)/?T(?+) from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive ?(±) electroproduction on the deuteron at central Q(2) values of 0.6, 1.0, 1.6??GeV(2) at W=1.95??GeV, and Q(2)=2.45??GeV(2) at W=2.22??GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms. PMID:24856691

Huber, G M; Blok, H P; Butuceanu, C; Gaskell, D; Horn, T; Mack, D J; Abbott, D; Aniol, K; Anklin, H; Armstrong, C; Arrington, J; Assamagan, K; Avery, S; Baker, O K; Barrett, B; Beise, E J; Bochna, C; Boeglin, W; Brash, E J; Breuer, H; Chang, C C; Chant, N; Christy, M E; Dunne, J; Eden, T; Ent, R; Fenker, H; Gibson, E F; Gilman, R; Gustafsson, K; Hinton, W; Holt, R J; Jackson, H; Jin, S; Jones, M K; Keppel, C E; Kim, P H; Kim, W; King, P M; Klein, A; Koltenuk, D; Kovaltchouk, V; Liang, M; Liu, J; Lolos, G J; Lung, A; Margaziotis, D J; Markowitz, P; Matsumura, A; McKee, D; Meekins, D; Mitchell, J; Miyoshi, T; Mkrtchyan, H; Mueller, B; Niculescu, G; Niculescu, I; Okayasu, Y; Pentchev, L; Perdrisat, C; Pitz, D; Potterveld, D; Punjabi, V; Qin, L M; Reimer, P E; Reinhold, J; Roche, J; Roos, P G; Sarty, A; Shin, I K; Smith, G R; Stepanyan, S; Tang, L G; Tadevosyan, V; Tvaskis, V; van der Meer, R L J; Vansyoc, K; Van Westrum, D; Vidakovic, S; Volmer, J; Vulcan, W; Warren, G; Wood, S A; Xu, C; Yan, C; Zhao, W-X; Zheng, X; Zihlmann, B



Sex ratio at birth in Croatia: update.  


There is strong evidence that the sex ratio at birth is partially determined by environmental and social factors. The modern change in those factors serves as an explanation for the secular decline in sex ratio at birth in most of the industrialized countries. This article is the reexamination of the results from my previous communication in which no trend in sex ratio at birth was established for the Croatian data from 1946 to 2007. The data for the years 2008 to 2011 were added, which didn't result with the detection of a significant change in sex ratio at birth by the regression analysis or by the Box-Jenkins time series analysis. Although the numerous factors associated with the decline in sex ratio at birth did occur during the studied period (e.g. increased exposure to the environmental pollution through food, air and water, the rise of the obesity and diabetes incidence, the economic crisis etc.), it appears that none of them made the measurable impact on sex ratio at birth. Also, the possible marginally significant decline in sex ratio at birth could be the result of a high sex ratio at birth immediately after the World War II. The results of this study caution against rapid generalization of the factors found to influence the sex ratio at birth in the epidemiological and clinical studies on the population level data. PMID:25144988

Pavi?, Dario



Arnold Schwarzenegger THE CENTRAL CALIFORNIA  

E-print Network

Arnold Schwarzenegger Governor THE CENTRAL CALIFORNIA OZONE STUDY APPENDIX C: CENTRAL CALIFORNIA OZONE STUDY VOLUME 3: SUMMARY OF FIELD OPERATIONS Prepared For: California Energy Commission Public Interest Energy Research Program Prepared By: California Air Resources Board PIERFINALPROJECTREPORT March


Arnold Schwarzenegger THE CENTRAL CALIFORNIA  

E-print Network

Arnold Schwarzenegger Governor THE CENTRAL CALIFORNIA OZONE STUDY APPENDIX B: CENTRAL CALIFORNIA OZONE STUDY VOLUME 2: FIELD OPERATIONS PLAN Prepared For: California Energy Commission Public Interest Energy Research Program Prepared By: California Air Resources Board PIERFINALPROJECTREPORT March 2007 CEC


Arnold Schwarzenegger THE CENTRAL CALIFORNIA  

E-print Network

Arnold Schwarzenegger Governor THE CENTRAL CALIFORNIA OZONE STUDY APPENDIX A: CENTRAL CALIFORNIA OZONE STUDY VOLUME 1: FIELD STUDY PLAN Prepared For: California Energy Commission Public Interest Energy Research Program Prepared By: California Air Resources Board PIERFINALPROJECTREPORT March 2007 CEC-500


The DO Central Track Trigger  

E-print Network

An overview of the system architecture and algorithms used for the DO Central Track Trigger (CTT) in the Run 2 of the Fermilab Tevatron Proton-Antiproton Collider is presented. This system uses information from the newly commissioned Central Fiber...

Wilson, Graham Wallace; Desai, S.; Cooke, Michael; Connolly, B.; Borcherding, F.; Blazey, G.; Bhattacharjee, M.; Babukhadia, L.; Angstadt, R.; Anderson, John; Olsen, J.



Central ignition scenarios for TFTR  

SciTech Connect

The possibility of obtaining ignition in TFTR by means of very centrally peaked density profiles is examined. It is shown that local central alpha heating can be made to exceed local central energy losses (''central ignition'') under global conditions for which Q greater than or equal to 1. Time dependent 1-D transport simulations show that the normal global ignition requirements are substantially relaxed for plasmas with peaked density profiles. 18 refs., 18 figs.

Zweben, S.J.; Redi, M.H.; Bateman, G.




E-print Network

MISSION STATEMENT OF THE CENTRAL ADMINISTRATION #12;MISSION STATEMENT OF THE CENTRAL ADMINISTRATION University Mainz, Professor Dr. Georg Krausch Concept / Text: Mission Statement of the Central Administration statement which creates a joint framework for research, teaching, and the administration. As a first step

Kaus, Boris


Response surface and neural network models for performance of broiler chicks fed diets varying in digestible protein and critical amino acids from 11 to 17 days of age.  


Central composite design (CCD; 5 levels and 4 factors), response surface methodology (RSM), and artificial neural network-genetic algorithm (ANN-GA) were used to evaluate the response of broiler chicks [ADG and feed conversion ratio (FCR)] to dietary standardized ileal digestible protein (dP), lysine (dLys), total sulfur amino acids (dTSAA), and threonine (dThr). A total of 84 battery brooder units of 5 birds each were assigned to 28 diets of CCD containing 5 levels of dP (18-22%), dLys (1.06-1.30%), dTSAA (0.81-1.01%), and dThr (0.66-0.86%) from 11 to 17 d of age. The experimental results of CCD were fitted with the quadratic and artificial neural network models. A ridge analysis (for RSM models) and a genetic algorithm (for ANN-GA models) were used to compute the optimal response for ADG and FCR. For both ADG and FCR, the goodness of fit in terms of R(2) and MS error corresponding to ANN-GA and RSM models showed a substantially higher accuracy of prediction for ANN models (ADG model: R(2) = 0.99; FCR model: R(2) = 0.97) compared with RSM models (ADG model: R(2) = 0.70; FCR model: R(2) = 0.71). The ridge maximum analysis on ADG and minimum analysis on FCR models revealed that the maximum ADG may be obtained with 18.5, 1.10, 0.89, and 0.73% dP, dLys, dTSAA, and dThr, respectively, in diet, and minimum FCR may be obtained with 19.44, 1.18, 0.90, and 0.75% of dP, dLys, dTSAA, and dThr, respectively, in diet. The optimization results of ANN-GA models showed the maximum ADG may be achieved with 19.93, 1.06, 0.90, and 0.76% of dP, dLys, dTSAA, and dThr, respectively, in diet, and minimum FCR may be achieved with 18.63, 1.26, 0.84, and 0.69% of dP, dLys, dTSAA, and dThr, respectively, in diet. The results of this study revealed that the platform of CCD (for conducting growth trials with minimum treatments), RSM model, and ANN-GA (for experimental data modeling and optimization) may be used to describe the relationship between dietary nutrient concentrations and broiler performance to achieve the optimal target. PMID:21844277

Ahmadi, H; Golian, A



Morphology, photometry and kinematics of N -body bars - I. Three models with different halo central concentrations  

Microsoft Academic Search

We discuss the morphology, photometry and kinematics of the bars which have formed in three N -body simulations. These have initially the same disc and the same halo-to-disc mass ratio, but their haloes have very different central concentrations. The third model includes a bulge. The bar in the model with the centrally concentrated halo (model MH) is much stronger, longer

E. Athanassoula; A. Misiriotis



Central American electrical interconnection  

SciTech Connect

A technical cooperation grant of $2.25 million, designed to strengthen the capacity of Central American countries to operate their regional interconnected electrical system, was announced by the Inter-American Development Bank (IDB). The grant, extended from the banks Fund for Special Operations, will help improve the capacity of the regions electric power companies to achieve economical, safe operation of the interconnected electric power systems. The funds will also be used to finance regional studies of the accords, procedures, regulations, and supervisory mechanisms for the system, as well as program development and data bases.

Not Available



Central Europe Online  

NSDL National Science Digital Library

This website, a service of the European Internet Network, brings English-language news and background to users each weekday. Central Europe Online covers the Czech Republic, Poland, Hungary, Slovakia, and Slovenia. The site offers current headlines (along with the time that they were most recently updated), business news, travel information, and links to local media. New stories are drawn primarily from Reuters. An archive holds back issues. Users who want to stay current on issues affecting these regions will benefit from the professional approach this site brings to coverage.



Fires in Central Africa  

NASA Technical Reports Server (NTRS)

Hundreds of fires are set every year during the dry season in Central Africa. This true color image from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) shows dozens of smoke plumes in the Democratic Republic of the Congo on June 29, 2000. Residents burn away scrub and brush annually in the woody savanna to clear land for farming and grazing. For more information, visit the SeaWiFS Home Page, Global Fire Monitoring Fact Sheet, and 4km2 Fire Data Image Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE



Flooding in Central Siberia  

NASA Technical Reports Server (NTRS)

A mixture of snowmelt and ice jams in late May and June of this year caused the Taz River (left) and the Yenisey River (right) in central Siberia to overflow their banks. The flooding can be seen in this image taken on June 11, 2002, by the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard the Terra satellite. Normally, the rivers would resemble thin black lines in MODIS imagery. In the false-color images sage green and rusty orange is land, and water is black. Clouds are white and pink. Credit: Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC



Central American resource studies  

SciTech Connect

Los Alamos National Laboratory has been working with five Central American countries to assist in the development of their energy and mineral resources. Since 1985, mineral resources in Costa Rica, peat resources in Costa Rica and Panama, geothermal energy resources in Honduras and Guatemala, and geothermal field development in El Salvador and Costa Rica have been topics of study. This paper presents an overview of this work -- within these proceedings are papers that deal with specific aspects of each topic, and these will be duly noted. 15 refs., 4 figs.

Van Eeckhout, E.; Laughlin, A.W.



Imaging of central neurocytomas.  


Central neurocytoma (CN) is an important consideration in the differential diagnosis of any intraventricular lesion. Initial evaluation should include noncontrast CT, MRI with and without gadolinium contrast, and magnetic resonance (MR) spectroscopy, if available. CN classically appear as a partially calcified mass on CT, arising from the septum pellucidum or foramen of Monro, with a soap-bubble multicystic appearance on MR T2-imaging and heterogeneous enhancement on MR T1 postcontrast imaging. MR perfusion/permeability and dynamic contrast imaging are experimental and promising tools in the diagnosis of CN. PMID:25432179

Donoho, Daniel; Zada, Gabriel



A low aspect ratio tokamak transmutation system  

Microsoft Academic Search

A low aspect ratio tokamak transmutation system is proposed as an alternative application of fusion energy on the basis of a review of previous studies. This system includes: (1) a low aspect ratio tokamak as fusion neutron driver, (2) a radioactivity-clean nuclear power system as blanket, and (3) a novel concept of liquid metal centre conductor post as part of

L. J. Qiu; Y. C. Wu; B. J. Xiao; Q. Xu; Q. Y. Huang; B. Wu; Y. X. Chen; W. N. Xu; Y. P. Chen; X. P. Liu



On the Calibration of Likelihood Ratios  

E-print Network

in Forensic Sciences #12;Likelihood Ratios (LR) in Forensic Science Given two materials to compare Evidence;Outline Likelihood Ratio (LR) Framework in Forensic Science Assessing LR Performance C lib ti f LR l a suspect... Relevant hypotheses (at source level) Hypothesis p : materials come from the same source

Autonoma de Madrid, Universidad


The Divine Ratio and Golden Rectangles.  

ERIC Educational Resources Information Center

The material examines aspects of Fibonacci and Lucas sequences, the generation of the Divine Ratio, and the nature of this ratio in golden rectangles, triangles, and figures made up of golden triangles. It is noted Lucas sequence is formed like Fibonacci but has one and three as the first elements. (Author/MP)

Cooper, Martin



The Golden Ratio--A Contrary Viewpoint  

ERIC Educational Resources Information Center

Many assertions about the occurrence of the golden ratio phi in art, architecture, and nature have been shown to be false, unsupported, or misleading. For instance, we show that the spirals found in sea shells, in particular the "Nautilus pompilius," are not in the shape of the golden ratio, as is often claimed. Some of the most interesting…

Falbo, Clement



Economy Track: Employment to Population Ratio  

NSDL National Science Digital Library

Time plot compares the employment-population ratio - the broadest measure of people who are working in America. Allows to compare between recessions, also allows to compare between demographic groups -- by sex, race/ethnicity and educational attainment. Also shows the secular trend for employment-population ratio since 1973.

Institute, Economic P.


Georgia Tech Profiling Overconsolidation Ratio in  

E-print Network

Georgia Tech Profiling Overconsolidation Ratio in Clays by Piezocone and Flat Dilatometer Tests Properties: M = 6 sin'/(3-sin') ' = effective stress friction angle Cc = compression index Cs = swelling Clay Chamber Tests 0 200 400 600 800 1000 1200 0 10 20 30 40 Overconsolidation Ratio, OCR Depth

Mayne, Paul W.


Momentum subtraction and the R-ratio  

E-print Network

We determine the R-ratio for massless quarks in several renormalization schemes to various loop orders. These are the momentum subtraction schemes of Celmaster and Gonsalves as well as the minimal momentum subtraction scheme. The dependence of the R-ratio on the schemes is analysed.

J. A. Gracey




Microsoft Academic Search

Dynamically Programmable Cache is a Reconfigurable Cache designed for General Purpose Microprocessor with multimedia applications. This paper evaluates the performance of DPC as a coprocessor accelerator with FPGA fabric integrated on it. DPC stores its FPGA configurations in the cache, which may affect the hit\\/miss ratio of this cache. This paper shows small effect induced on the miss ratio due

Mouna Nakkar



Effects of Thermal Conductivity Ratio in  

E-print Network

Effects of Thermal Conductivity Ratio in Helium-Cooled Divertors B. H. Mills J. D. Rader D. L conductivity ratio Verify previous predictions of thermal performance at prototypical conditions and general But He has higher thermal conductivity k Matching Re not sufficient for similarity Multi


The Gyromagnetic Ratios of the Ferromagnetic Elements  

Microsoft Academic Search

The gyromagnetic ratios for the three ferromagnetic elements have been determined by means of a technique involving a sensitive torsional pendulum. The final values obtained, in terms of the mass-to-charge ratio of the electron, are: iron 1.028+\\/-0.001 cobalt 1.068+\\/-0.004 and nickel 1.078+\\/-0.002.

G. G. Scott



Measurement of the ? ? ?? decay branching ratio  

Microsoft Academic Search

We have measured the branching ratio for the radiative decay ? ? ?? with ? mesons produced in antiproton-proton annihilation at rest into ?0? and ??. Taking into account ? - ? mixing we find a branching ratio B(? ? ??) = (6.6 ± 1.7) × 10?4, in accord with the constructive interference solution in other experiments. The upper-limit for

A. Abele; J. Adomeit; C. Amsler; C. A. Baker; B. M. Barnett; C. J. Batty; M. Benayoun; A. Berdoz; K. Beuchert; S. Bischoff; P. Blüm; K. Braune; D. V. Bugg; T. Case; A. Cooper; O. Cramer; K. M. Crowe; V. Credé; T. Degener; N. Djaoshvili; S. v. Dombrowski; M. Doser; W. Dünnweber; A. Ehmanns; D. Engelhardt; M. A. Faessler; P. Giarritta; R. Hackmann; R. P. Haddock; F. H. Heinsius; M. Heinzelmann; M. Herz; N. P. Hessey; P. Hidas; C. Hodd; C. Holtzhaußen; D. Jamnik; H. Kalinowsky; B. Kalteyer; B. Kämmle; P. Kammel; J. Kisiel; E. Klempt; H. Koch; C. Kolo; U. Kurilla; M. Kunze; M. Lakata; R. Landua; J. Lüdemann; H. Matthäy; R. McCrady; J. Meier; C. A. Meyer; L. Montanet; R. Ouared; F. Ould-Saada; K. Peters; B. Pick; C. Pietra; C. N. Pinder; M. Ratajczak; C. Regenfus; S. Resag; W. Roethel; P. Schmidt; I. Scott; R. Seibert; S. Spanier; H. Stöck; C. Straßburger; U. Strohbusch; M. Suffert; U. Thoma; M. Tischhäuser; C. Völcker; S. Wallis; D. Walther; U. Wiedner; B. S. Zou



Osmosis and Surface Area to Volume Ratio.  

ERIC Educational Resources Information Center

Describes an experiment designed to help students understand the concepts of osmosis and surface area to volume ratio (SA:VOL). The task for students is to compare water uptake in different sizes of potato cubes and relate differences to their SA:VOL ratios. (JN)

Barrett, D. R. B.



Student Learning Centre Ratio and Proportion  

E-print Network

Student Learning Centre 1 of 2 Ratio and Proportion A ratio compares the sizes of two quantities. A proportion describes the relationship of a part to the whole. Example 1 In a laboratory class of students of students in the class is 40 so the proportion or fractional share of males in the class is 16 40 2 5


CCSSM Challenge: Graphing Ratio and Proportion  

ERIC Educational Resources Information Center

A renewed emphasis was placed on ratio and proportional reasoning in the middle grades in the Common Core State Standards for Mathematics (CCSSM). The expectation for students includes the ability to not only compute and then compare and interpret the results of computations in context but also interpret ratios and proportions as they are…

Kastberg, Signe E.; D'Ambrosio, Beatriz S.; Lynch-Davis, Kathleen; Mintos, Alexia; Krawczyk, Kathryn



Ratio model serves suprathreshold color luminance discrimination  

E-print Network

Ratio model serves suprathreshold color­ luminance discrimination Marcel J. Sankeralli and Kathy T the responses of the three postreceptoral mechanisms are combined to subserve discrimination of suprathreshold model of suprathreshold color­luminance dis- crimination, in which discrimination depends on a ratio

Mullen, Kathy T.


Empirical Analysis of Drill Ratio Research  

ERIC Educational Resources Information Center

Providing students an appropriate level of challenge, called the instructional level, is an important component of effective instruction. Research regarding the optimal ratio of known to unknown items for drill tasks has been inconsistent. The author of the current article conducted an empirical metaanalysis of research on drill ratios by using…

Burns, M.K.



High Transformer ratios in collinear wakefield accelerators.  

SciTech Connect

Based on our previous experiment that successfully demonstrated wakefield transformer ratio enhancement in a 13.625 GHz dielectric-loaded collinear wakefield accelerator using the ramped bunch train technique, we present here a redesigned experimental scheme for even higher enhancement of the efficiency of this accelerator. Design of a collinear wakefield device with a transformer ratio R2, is presented. Using a ramped bunch train (RBT) rather than a single drive bunch, the enhanced transformer ratio (ETR) technique is able to increase the transformer ratio R above the ordinary limit of 2. To match the wavelength of the fundamental mode of the wakefield with the bunch length (sigmaz=2 mm) of the new Argonne wakefield accelerator (AWA) drive gun (where the experiment will be performed), a 26.625 GHz dielectric based accelerating structure is required. This transformer ratio enhancement technique based on our dielectric-loaded waveguide design will result in a compact, high efficiency accelerating structures for future wakefield accelerators.

Power, J. G.; Conde, M.; Yusof, Z.; Gai, W.; Jing, C.; Kanreykin, A.; Schoessow, P.; High Energy Physics; Euclid Techlabs, LLC



Scavenging ratios based on inflow air concentrations  

SciTech Connect

Scavenging ratios were calculated from field measurements made during April 1985. Event precipitation samples were collected at the surface, but air chemistry measurements in the air mass feeding the precipitation were made from an aircraft. In contrast, ratios calculated in previous studies have used air concentration and precipitation chemistry data from only surface measurements. Average scavenging ratios were calculated for SO{sub 4}{sup 2{minus}}, NO{sub 3}{sup {minus}}, NH{sub 4}{sup +}, total sulfate, total nitrate, and total ammonium for 5 events; the geometric mean of these scavenging ratios were 8.5 {times} 10{sup 5}, 5.6 {times} 10{sup 6}, 4.3 {times} 10{sup 5}, 3.4 {times} 10{sup 5}, 2.4 {times} 10{sup 6}, and 9.7 {times} 10{sup 4}, respectively. These means are similar to but less variable than previous ratios formed using only surface data.

Davis, W.E.; Dana, M.T.; Lee, R.N.; Slinn, W.G.N.; Thorp, J.M.



CALIPSO lidar ratio retrieval over the ocean.  


We are demonstrating on a few cases the capability of CALIPSO to retrieve the 532 nm lidar ratio over the ocean when CloudSat surface scattering cross section is used as a constraint. We are presenting the algorithm used and comparisons with the column lidar ratio retrieved by the NASA airborne high spectral resolution lidar. For the three cases presented here, the agreement is fairly good. The average CALIPSO 532 nm column lidar ratio bias is 13.7% relative to HSRL, and the relative standard deviation is 13.6%. Considering the natural variability of aerosol microphysical properties, this level of accuracy is significant since the lidar ratio is a good indicator of aerosol types. We are discussing dependencies of the accuracy of retrieved aerosol lidar ratio on atmospheric aerosol homogeneity, lidar signal to noise ratio, and errors in the optical depth retrievals. We are obtaining the best result (bias 7% and standard deviation around 6%) for a nighttime case with a relatively constant lidar ratio (in the vertical) indicative of homogeneous aerosol type. PMID:21935239

Josset, Damien; Rogers, Raymond; Pelon, Jacques; Hu, Yongxiang; Liu, Zhaoyan; Omar, Ali; Zhai, Peng-Wang



CALIPSO Lidar Ratio Retrieval Over the Ocean  

NASA Technical Reports Server (NTRS)

We are demonstrating on a few cases the capability of CALIPSO to retrieve the 532 nm lidar ratio over the ocean when CloudSat surface scattering cross section is used as a constraint. We are presenting the algorithm used and comparisons with the column lidar ratio retrieved by the NASA airborne high spectral resolution lidar. For the three cases presented here, the agreement is fairly good. The average CALIPSO 532 nm column lidar ratio bias is 13.7% relative to HSRL, and the relative standard deviation is 13.6%. Considering the natural variability of aerosol microphysical properties, this level of accuracy is significant since the lidar ratio is a good indicator of aerosol types. We are discussing dependencies of the accuracy of retrieved aerosol lidar ratio on atmospheric aerosol homogeneity, lidar signal to noise ratio, and errors in the optical depth retrievals. We are obtaining the best result (bias 7% and standard deviation around 6%) for a nighttime case with a relatively constant lidar ratio (in the vertical) indicative of homogeneous aerosol type

Josset, Damien B.; Rogers, Raymond R.; Pelon, Jacques; Hu, Yongxiang; Liu, Zhaoyan; Omar, Ali H.; Zhai, Peng-Wang



Optimal sampling ratios in comparative diagnostic trials  

PubMed Central

Summary A subjective sampling ratio between the case and the control groups is not always an efficient choice to maximize the power or to minimize the total required sample size in comparative diagnostic trials.We derive explicit expressions for an optimal sampling ratio based on a common variance structure shared by several existing summary statistics of the receiver operating characteristic curve. We propose a two-stage procedure to estimate adaptively the optimal ratio without pilot data. We investigate the properties of the proposed method through theoretical proofs, extensive simulation studies and a real example in cancer diagnostic studies. PMID:24948841

Dong, Ting; Tang, Liansheng Larry; Rosenberger, William F.



Future Flight Central  

NASA Technical Reports Server (NTRS)

NASA 'Future Flight Central,' the world's first full-scale virtual airport control tower, opened December 13, 1999 at NASA Ames Research Center, Moffett Field, California. Constructed at a cost of $10 million, the two story facility was jointly funded by NASA and the Federal Aviation Administration (FAA). The facility is designed to test ways to solve potential air and ground traffic problems at commercial airports under realistic airport conditions and configurations. The facility provides an opportunity for airlines and airports to mitigate passenger delays by fine tuning airport hub operations, gate management, ramp movement procedures, and various other airport improvements. Twelve rear projection screens provide a seamless 360 degree high- resolution view of the airport or other screens being depicted. The imaging system, powered by supercomputers, provides a realistic view of weather conditions, enviromental and seasonal effects and the movement of up to 200 active aircraft and ground vehicles.



Rapidity dependence of antiproton-to-proton ratios in Au+Au collisions at root s(NN)=130 GeV  

E-print Network

Measurements, with the BRAHMS detector, of the antiproton-to-proton ratio at midrapidities and forward rapidities, are presented for Au + Au reactions at roots(NN) = 130 GeV, and for three different collision centralities. ...

Sanders, Stephen J.



Central Michigan University  

NSDL National Science Digital Library

Central Michigan University serves Michigan and the larger community as a doctoral/research intensive public university focused on excellent teaching and student-focused learning. The University is committed to providing a broad range of undergraduate and graduate programs and services to prepare its students for varied roles as responsible citizens and leaders in a democratic and diverse society. Its programs encourage intellectual and moral growth, prepare students for meaningful careers and professions, instill the values of lifelong learning, and encourage civic responsibility, public service and understanding among social groups in a global society. The university emphasizes an undergraduate program that maintains a balance between general education and specialization. In addition to educational depth in at least one academic discipline or professional field, the university provides educational experiences in the arts, humanities, natural and social sciences, global cultures, and issues of race and diversity. The university offers selected high quality graduate programs in traditional disciplines and professional fields. Through its College of Extended Learning, the university provides access to higher education programs and lifelong learning opportunities both nationally and internationally through a variety of innovative instructional methods and schedules designed to meet the demands of adult populations. Central Michigan University encourages research, scholarship and creative activity and promotes the scholarly pursuit and dissemination of new knowledge, artistic production and applied research. Through its support of research, the university enhances the learning opportunities of both its undergraduate and graduate students and promotes economic, cultural and social development. The university?s sense of community is reflected through governance structures that allow broadbased participation, opportunities for close student-faculty interaction, and a rich array of residential and campus-based co-curricular activities. Through its partnerships and outreach efforts, the university promotes learning outsideof the traditional classroom and enhances the general welfare of society.

Central Michigan University


Optimizing an irreversible Diesel cycle — fine tuning of compression ratio and cut-off ratio  

Microsoft Academic Search

A simplified irreversible model has been proposed for the air standard Diesel cycle. Global thermal and friction losses have been lumped into an equivalent friction term. Optimization of the cycle has been performed for power output as well as for thermal efficiency with respect to compression ratio and cut-off ratio. The optimum values of these ratios compare well with standard

Souvik Bhattacharyya



Ratio and Proportion A ratio compares the sizes of two quantities. A proportion describes the relationship  

E-print Network

Ratio and Proportion A ratio compares the sizes of two quantities. A proportion describes in the class is 16+24 = 40 so the proportion or fractional share of males in the class is 16 40 2 5 and the proportion of females in the class is 24 40 3 5 Note that the ratio of males to females is equivalent


Science Application of Area and Ratio Concepts  

ERIC Educational Resources Information Center

This article describes using area and ratio concepts to examine why some animals, or people wearing different types of shoes, sink into the surface on which they are standing. Students compute "sinking values" to explain these differences. (Contains 2 figures.)

Horak, Virginia M.



Gyromagnetic ratio of a black hole  

SciTech Connect

We examine the properties of a rotating loop of charged matter in the presence of a static charged black hole. The behavior of the gyromagnetic ratio is examined in the limit as the radius of the loop becomes very large and in the limit as the loop radius approaches the radius of the black hole's event horizon. The implications of these results for the gyromagnetic ratio of a black hole are discussed. For large radii of the loop the gyromagnetic ratio reduces to the value computed for a loop in classical electromagnetism, which has {ital g}=1. As the radius of the loop approaches the horizon, the ratio approaches that for a black hole which has {ital g}=2, like an electron. The latter result is also true for a {ital neutral} loop; hence, magnetic-monopole black holes that accrete matter with angular momentum have gravitationally induced electric fields.

Garfinkle, D. (University of California, Santa Barbara, CA (USA). Department of Physics); Traschen, J. (University of Massachusetts, Amherst, MA (USA). Department of Physics and Astronomy)



Posterior odds ratios for selected regression hypotheses  

Microsoft Academic Search

Summary  Bayesian posterior odds ratios for frequently encountered hypotheses about parameters of the normal linear multiple regression\\u000a model are derived and discussed. For the particular prior distributions utilized, it is found that the posterior odds ratios\\u000a can be well approximated by functions that are monotonic in usual sampling theoryF statistics. Some implications of this finding and the relation of our work

A. Zellner; A. Siow



Measurement of the ?-->?? decay branching ratio  

NASA Astrophysics Data System (ADS)

We have measured the branching ratio for the radiative decay ?-->?? with ? mesons produced in antiproton-proton annihilation at rest into ?0? and ??. Taking into account ?-? mixing we find a branching ratio B(?-->??)=(6.6+/-1.7)x10-4, in accord with the constructive interference solution in other experiments. The upper-limit for the direct radiative decay ?-->3? is 1.9x10-4 at 95% confidence level.

Crystal Barrel Collaboration; Abele, A.; Adomeit, J.; Amsler, C.; Baker, C. A.; Barnett, B. M.; Batty, C. J.; Benayoun, M.; Berdoz, A.; Beuchert, K.; Bischoff, S.; Blüm, P.; Braune, K.; Bugg, D. V.; Case, T.; Cooper, A.; Cramer, O.; Crowe, K. M.; Credé, V.; Degener, T.; Djaoshvili, N.; Dombrowski, S. V.; Doser, M.; Dünnweber, W.; Ehmanns, A.; Engelhardt, D.; Faessler, M. A.; Giarritta, P.; Hackmann, R.; Haddock, R. P.; Heinsius, F. H.; Heinzelmann, M.; Herz, M.; Hessey, N. P.; Hidas, P.; Hodd, C.; Holtzhaußen, C.; Jamnik, D.; Kalinowsky, H.; Kalteyer, B.; Kämmle, B.; Kammel, P.; Kisiel, J.; Klempt, E.; Koch, H.; Kolo, C.; Kurilla, U.; Kunze, M.; Lakata, M.; Landua, R.; Lüdemann, J.; Matthäy, H.; McCrady, R.; Meier, J.; Meyer, C. A.; Montanet, L.; Ouared, R.; Ould-Saada, F.; Peters, K.; Pick, B.; Pietra, C.; Pinder, C. N.; Ratajczak, M.; Regenfus, C.; Resag, S.; Roethel, W.; Schmidt, P.; Scott, I.; Seibert, R.; Spanier, S.; Stöck, H.; Straßburger, C.; Strohbusch, U.; Suffert, M.; Thoma, U.; Tischhäuser, M.; Völcker, C.; Wallis, S.; Walther, D.; Wiedner, U.; Zou, B. S.



Approaches to high aspect ratio triangulations  

NASA Technical Reports Server (NTRS)

In aerospace computational fluid dynamics calculations, high aspect ratio, or stretched, triangulations are necessary to adequately resolve the features of a viscous flow around bodies. In this paper, we explore alternatives to the Delaunay triangulation which can be used to generate high aspect ratio triangulations of point sets. The method is based on a variation of the lifting map concept which derives Delaunay triangulations from convex hull calculations.

Posenau, M.-A.



Plutonium isotope ratio variations in North America  

SciTech Connect

Historically, approximately 12,000 TBq of plutonium was distributed throughout the global biosphere by thermo nuclear weapons testing. The resultant global plutonium fallout is a complex mixture whose {sup 240}Pu/{sup 239}Pu atom ratio is a function of the design and yield of the devices tested. The average {sup 240}Pu/{sup 239}Pu atom ratio in global fallout is 0.176 + 014. However, the {sup 240}Pu/{sup 239}Pu atom ratio at any location may differ significantly from 0.176. Plutonium has also been released by discharges and accidents associated with the commercial and weapons related nuclear industries. At many locations contributions from this plutonium significantly alters the {sup 240}Pu/{sup 239}Pu atom ratios from those observed in global fallout. We have measured the {sup 240}Pu/{sup 239}Pu atom ratios in environmental samples collected from many locations in North America. This presentation will summarize the analytical results from these measurements. Special emphasis will be placed on interpretation of the significance of the {sup 240}Pu/{sup 239}Pu atom ratios measured in environmental samples collected in the Arctic and in the western portions of the United States.

Steiner, Robert E [Los Alamos National Laboratory; La Mont, Stephen P [Los Alamos National Laboratory; Eisele, William F [Los Alamos National Laboratory; Fresquez, Philip R [Los Alamos National Laboratory; Mc Naughton, Michael [Los Alamos National Laboratory; Whicker, Jeffrey J [Los Alamos National Laboratory



Energy Distribution Ratio into Micro EDM Electrodes  

NASA Astrophysics Data System (ADS)

Energy distribution ratio into micro EDM electrodes was determined based on the summation between the ratio of energy loss due to heat conduction within electrodes and ratio of energy carried away by debris. Ratio of energy loss due to heat conduction was obtained by comparing the measured and calculated temperature rise on electrode after igniting plural pulses discharges. On the other hand, the ratio of energy carried away by debris was calculated based on the measured removal volume. Energy distribution ratio into micro EDM anode and cathode was between 10% and 15% in total which was comparatively lower than that of macro EDM. This is because much larger fraction of the total discharge energy is consumed for the generation and enthalphy increase of the plasma in the early stage of discharge. Besides, unlike macro EDM the energy carried away by debris in micro EDM cannot be ignored compared with the energy lost due to heat conduction. This means, the energy consumption by material removal in micro EDM with regard to the energy distributed into the electrodes is more efficient compared to that of macro EDM.

Zahiruddin, Mohd; Kunieda, Masanori


Localization and centrality in networks  

NASA Astrophysics Data System (ADS)

Eigenvector centrality is a common measure of the importance of nodes in a network. Here we show that under common conditions the eigenvector centrality displays a localization transition that causes most of the weight of the centrality to concentrate on a small number of nodes in the network. In this regime the measure is no longer useful for distinguishing among the remaining nodes and its efficacy as a network metric is impaired. As a remedy, we propose an alternative centrality measure based on the nonbacktracking matrix, which gives results closely similar to the standard eigenvector centrality in dense networks where the latter is well behaved but avoids localization and gives useful results in regimes where the standard centrality fails.

Martin, Travis; Zhang, Xiao; Newman, M. E. J.



240Pu/239Pu mass ratio in environmental samples in Finland.  


The (240)Pu/(239)Pu mass ratio was determined with SF-ICP-MS in lichen, peat, grass, air filter, and hot particle samples obtained in Finland. The main part of the air filters were sampled in northern Finland in 1963, whereas all the other samples were collected in southern and central Finland immediately after the Chernobyl accident in 1986. The (240)Pu/(239)Pu mass ratio varied between 0.13 ± 0.01 and 0.53 ± 0.03 in the environmental samples analyzed. The values for the (240)Pu/(239)Pu ratio confirm previous estimations, based on the (238)Pu/(239+240)Pu alpha activity ratio in the same samples, that global fallout from nuclear weapons testing and deposition from the Chernobyl accident have been the main Pu contamination sources in the environment in Finland. PMID:22776691

Salminen-Paatero, S; Nygren, U; Paatero, J



Collisional Transport in a Low Aspect Ratio Tokamak -- Beyond the Drift Kinetic Formalism  

SciTech Connect

Calculations of collisional thermal and particle diffusivities in toroidal magnetic plasma confinement devices order the toroidal gyroradius to be small relative to the poloidal gyroradius. This ordering is central to what is usually referred to as neoclassical transport theory. This ordering is incorrect at low aspect ratio, where it can often be the case that the toroidal gyroradius is larger than the poloidal gyroradius. We calculate the correction to the particle and thermal diffusivities at low aspect ratio by comparing the diffusivities as determined by a full orbit code (which we refer to as omni-classical diffusion) with those from a gyroaveraged orbit code (neoclassical diffusion). In typical low aspect ratio devices the omni-classical diffusion can be up to 2.5 times the calculated neoclassical value. We discuss the implications of this work on the analysis of collisional transport in low aspect ratio magnetic confinement experiments.

D.A. Gates; R.B. White



Separated Response Function Ratios in Exclusive, Forward pi^{+/-} Electroproduction  

E-print Network

The study of exclusive $\\pi^{\\pm}$ electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio $R_L=\\sigma_L^{\\pi^-}/\\sigma_L^{\\pi^+}$ is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of $R_T=\\sigma_T^{\\pi^-}/\\sigma_T^{\\pi^+}$ from unity at small $-t$, to 1/4 at large $-t$, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to pQCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive $\\pi^{\\pm}$ electroproduction on the deuteron at central $Q^2$ values of 0.6, 1.0, 1.6 GeV$^2$ at $W$=1.95 GeV, and $Q^2=2.45$ GeV$^2$ at $W$=2.22 GeV. Here, we present the $L$ and $T$ cross sections, with emphasis on $R_L$ and $R_T$, and compare them with theoretical calculations. Results for the separated ratio $R_L$ indicate dominance of the pion-pole diagram at low $-t$, while results for $R_T$ are consistent with a transition between pion knockout and quark knockout mechanisms.

G. M. Huber; H. P. Blok; C. Butuceanu; D. Gaskell; T. Horn; D. J. Mack; D. Abbott; K. Aniol; H. Anklin; C. Armstrong; J. Arrington; K. Assamagan; S. Avery; O. K. Baker; B. Barrett; E. J. Beise; C. Bochna; W. Boeglin; E. J. Brash; H. Breuer; C. C. Chang; N. Chant; M. E. Christy; J. Dunne; T. Eden; R. Ent; H. Fenker; E. F. Gibson; R. Gilman; K. Gustafsson; W. Hinton; R. J. Holt; H. Jackson; S. Jin; M. K. Jones; C. E. Keppel; P. H. Kim; W. Kim; P. M. King; A. Klein; D. Koltenuk; V. Kovaltchouk; M. Liang; J. Liu; G. J. Lolos; A. Lung; D. J. Margaziotis; P. Markowitz; A. Matsumura; D. McKee; D. Meekins; J. Mitchell; T. Miyoshi; H. Mkrtchyan; B. Mueller; G. Niculescu; I. Niculescu; Y. Okayasu; L. Pentchev; C. Perdrisat; D. Pitz; D. Potterveld; V. Punjabi; L. M. Qin; P. E. Reimer; J. Reinhold; J. Roche; P. G. Roos; A. Sarty; I. K. Shin; G. R. Smith; S. Stepanyan; L. G. Tang; V. Tadevosyan; V. Tvaskis; R. L. J. van der Meer; K. Vansyoc; D. Van Westrum; S. Vidakovic; J. Volmer; W. Vulcan; G. Warren; S. A. Wood; C. Xu; C. Yan; W. -X. Zhao; X. Zheng; B. Zihlmann



Congenital central hypoventilation syndrome.  


Congenital central hypoventilation syndrome (CCHS) is characterized by hypoventilation during sleep and impaired ventilatory responses to hypercapnia and hypoxemia. Most cases are sporadic and caused by de novo PHOX2B gene mutations, which are usually polyalanine repeat expansions. Physiological and neuroanatomical studies of genetically engineered mice and analyses of cellular responses to mutated Phox2b have shed light on the pathophysiological mechanisms of CCHS. Findings in Phox2b(27Ala/+) knock-in mice consisted of unstable breathing with apneas, absence of the ventilatory response to hypercapnia, death within a few hours after birth, and absence of the retrotrapezoid nucleus (RTN). Conditional mouse mutants in which Phox2b(27Ala) was targeted to the RTN also lacked the ventilatory response to hypercapnia at birth but survived to adulthood and developed a partial hypercapnia response. The therapeutic effects of desogestrel are being evaluated in clinical trials, and recent analyses of cellular responses to polyAla Phox2b aggregates have suggested new pharmacological approaches designed to counteract the toxic effects of mutated Phox2b. PMID:23692929

Ramanantsoa, N; Gallego, J



Audio/Visual Ratios in Commercial Filmstrips.  

ERIC Educational Resources Information Center

Developed by the Westinghouse Electric Corporation, Video Audio Compressed (VIDAC) is a compressed time, variable rate, still picture television system. This technology made it possible for a centralized library of audiovisual materials to be transmitted over a television channel in very short periods of time. In order to establish specifications…

Gulliford, Nancy L.


The p/pi ratio pT-dependence in the RHIC range od baryo-chemical potential  

E-print Network

The BRAHMS measurement of proton-to-pion ratios in Au+Au and p+p collisions at 62.4 and 200 GeV is presented as a function of transverse momentum and collision centrality within the pseudorapidity range 0 pi ratio measured for Au+Au system at 62.4 GeV, eta = 3.2 reaches astounding value of 8-10 at pT >= 1.5 GeV/c. For these energy and pseudorapidity interval no centrality dependency of p/pi ratio is observed. The baryon-to-meson ratio of nucleus-nucleus data are consistent with results obtained for p+p interactions.

N. Katrynska; P. Staszel



Trigonometry: Comparing Ratio and Unit Circle Methods  

E-print Network

Before the 1960s, introductory trigonometry was taught in Victorian schools using the ratio method, where trigonometric functions are defined as ratios of sides of right angled triangles. With the advent of "new maths", the unit circle method was introduced. This study explored differences between the two methods for teaching introductory trigonometry. Eight. classes of students were randomly allocated to either teaching method. The ratio method was found to be much more effective, resulting in better performance and retention in trigonometry and algebra, and more favourable attitudes. Two methods of introducing trigonometry Since the advent of the "new mathematics", two methods of teaching introductory trigonometry have been used in Victorian schools. For decades, introductory trigonometry had been taught to Year 9 and 10 students (average age 14 and 15) by the ratio method. In this method, the trigonometric functions are defined as the ratios of pairs of sides in a right angled triangle. From the early 1960s, an alternative "modern " method was advocated by some educationalists (Trende, 1962; Willis, 1967) as a more desirable

Margaret Kendal; Kaye Stacey


A new ratio for protocol categorization.  


The present review describes and validates a new ratio "S" created for matching predictability and balance between TP and TN. Validity of S was studied in a three-step process as follows: (i) S was applied to the data of a past study predicting cardiac output response to fluid bolus from response to passive leg raise (PLR); (ii) S was comparatively analyzed with traditional ratios by modeling different 2 ? 2 contingency tables in 1000 hypothetical patients; (iii) precision of S was compared with other ratios by computing random fluctuations in the same patients. In comparison to other ratios, S performs better in predicting the cardiac response to fluid bolus and supports more directly the clinical conclusions. When the proportion of false responses is high, S is close to the coefficient correlation (CC). When the proportion of true responses is high, S is the unique ratio that identifies the categorization that balances the proportion of TP and TN. The precision of S is close to that of CC. In conclusion, S should be considered for creating categories from quantitative variables; especially when matching predictability with balance between TP and TN is a concern. PMID:24738007

Squara, Pierre



Central American Grandparents Raising Grandchildren  

ERIC Educational Resources Information Center

This study documents the prevalence and profile of Central American grandparents raising grandchildren in the United States of America. Using nationally representative data from the Census 2000 Supplementary Survey, Central American grandparent caregivers are compared with their noncare-giving peers. Results indicate that nationally an estimated…

Fuller-Thomson, Esme; Minkler, Meredith



Optimal Contracts for Central Bankers  

Microsoft Academic Search

This paper adopts a principal-agent framework to determine how a central banker's incentives should be structured to induce the socially optimal policy. In contrast to previous findings using ad hoc targeting rules, the inflation bias of discretionary policy is eliminated and an optimal response to shocks is achieved by the optimal incentive contract, even in the presence of private central-bank

Carl E Walsh



Kinship Institutions and Sex Ratios in India  

PubMed Central

This article explores the relationship between kinship institutions and sex ratios in India at the turn of the twentieth century. Because kinship rules vary by caste, language, religion, and region, we construct sex ratios by these categories at the district level by using data from the 1901 Census of India for Punjab (North), Bengal (East), and Madras (South). We find that the male-to-female sex ratio varied positively with caste rank, fell as one moved from the North to the East and then to the South, was higher for Hindus than for Muslims, and was higher for northern Indo-Aryan speakers than for the southern Dravidian-speaking people. We argue that these systematic patterns in the data are consistent with variations in the institution of family, kinship, and inheritance. PMID:21308567




Magnetostrictive contribution to Poisson ratio of galfenol  

NASA Astrophysics Data System (ADS)

In this work we present a detailed study on the magnetostrictive contribution to Poisson ratio for samples under applied mechanical stress. Magnetic contributions to strain and Poisson ratio for cubic materials were derived by accounting elastic and magneto-elastic anisotropy contributions. We apply our theoretical results for a material of interest in magnetomechanics, namely, galfenol (Fe1-xGax). Our results show that there is a non-negligible magnetic contribution in the linear portion of the curve of stress versus strain. The rotation of the magnetization towards [110] crystallographic direction upon application of mechanical stress leads to an auxetic behavior, i.e., exhibiting Poisson ratio with negative values. This magnetic contribution to auxetic behavior provides a novel insight for the discussion of theoretical and experimental developments of materials that display unusual mechanical properties.

Paes, V. Z. C.; Mosca, D. H.



Algorithms for high aspect ratio oriented triangulations  

NASA Technical Reports Server (NTRS)

Grid generation plays an integral part in the solution of computational fluid dynamics problems for aerodynamics applications. A major difficulty with standard structured grid generation, which produces quadrilateral (or hexahedral) elements with implicit connectivity, has been the requirement for a great deal of human intervention in developing grids around complex configurations. This has led to investigations into unstructured grids with explicit connectivities, which are primarily composed of triangular (or tetrahedral) elements, although other subdivisions of convex cells may be used. The existence of large gradients in the solution of aerodynamic problems may be exploited to reduce the computational effort by using high aspect ratio elements in high gradient regions. However, the heuristic approaches currently in use do not adequately address this need for high aspect ratio unstructured grids. High aspect ratio triangulations very often produce the large angles that are to be avoided. Point generation techniques based on contour or front generation are judged to be the most promising in terms of being able to handle complicated multiple body objects, with this technique lending itself well to adaptivity. The eventual goal encompasses several phases: first, a partitioning phase, in which the Voronoi diagram of a set of points and line segments (the input set) will be generated to partition the input domain; second, a contour generation phase in which body-conforming contours are used to subdivide the partition further as well as introduce the foundation for aspect ratio control, and; third, a Steiner triangulation phase in which points are added to the partition to enable triangulation while controlling angle bounds and aspect ratio. This provides a combination of the advancing front/contour techniques and refinement. By using a front, aspect ratio can be better controlled. By using refinement, bounds on angles can be maintained, while attempting to minimize the number of Steiner points.

Posenau, Mary-Anne K.



Planning applications in East Central Florida  

NASA Technical Reports Server (NTRS)

The author has identified the following significant results. This is a study of applications of ERTS data to planning problems, especially as applicable to East Central Florida. The primary method has been computer analysis of digital data, with visual analysis of images serving to supplement the digital analysis. The principal method of analysis was supervised maximum likelihood classification, supplemented by density slicing and mapping of ratios of band intensities. Land-use maps have been prepared for several urban and non-urban sectors. Thematic maps have been found to be a useful form of the land-use maps. Change-monitoring has been found to be an appropriate and useful application. Mapping of marsh regions has been found effective and useful in this region. Local planners have participated in selecting training samples and in the checking and interpretation of results.

Hannah, J. W. (principal investigator); Thomas, G. L.; Esparza, F.; Millard, J. J.



The Central kpc of Galaxy Bulges  

E-print Network

We study the innermost regions of bulges with surface brightness data derived from combined HST/NICMOS and ground-based NIR profiles. Bulge profiles to 1-2 kpc may be fit with Sersic laws, and show a trend with bulge-to-disk ratio: low-B/D bulges are roughly exponential, whereas higher-B/D bulges show increasing Sersic shape index $n$, indicating higher peak central densities and more extended brightness tails. N-body models of accretion of satellites onto disk-bulge-halo galaxies show that satellite accretion contributes to the increase of the shape index $n$ as the bulge grows by accretion. The N-body results demonstrate that exponential profiles are fragile to merging, hence bulges with exponential surface brightness profiles cannot have experienced significant growth by accretion of dense satellites.

M. Balcells



[Mechanisms of central antitussives].  


This paper provides an overview of our current understanding of the central mechanisms of cough and antitussives. Systemic administration of 8-OH-DPAT at doses of 0.1 and 0.3 mg/kg, i.p. markedly reduced the number of coughs in rats in a dose-dependent manner. The antitussive effect of 8-OH-DPAT, dihydrocodeine and dextromethorphan significantly was reduced by pretreatment with methysergide, but not ketanserin. Therefore, it is possible to speculate that the 5-HT1 receptors, in particular the 5-HT1A receptors, may be more important than others with respect to the effect of antitussive drugs. DAMGO, a selective mu-opioid receptor agonist, and U-50,488H, a highly selective kappa-opioid receptor agonist, have potent antitussive effects when administered either i.c. or i.p. However, we did not observe a cough-depressant effect of DPDPE, a selective delta-opioid receptor agonist. These results indicate that the antitussive effects of opioids are mediated predominantly by mu- and kappa-opioid receptors. On the other hand, naloxonazine, a selective mu 1-opioid receptor antagonist, had no effect on the antitussive effects associated with i.c.v. DAMGO. These results indicate that mu 2-rather than mu 1-opioid receptors are involved in mu-opioid receptor-induced antitussive effects. Antitussive effects of dextromethorphan and noscapine were significantly and dose-dependently reduced by pretreatment with rimcazole, a specific antagonist of sigma sites. However, rimcazole did not have a significant effect on the antitussive effect of morphine. These results suggest that sigma sites may be involved in the antitussive mechanism of non-narcotic antitussive drugs. PMID:9720082

Kamei, J



Central and southern Africa  

SciTech Connect

Exploration in central and southern Africa continued to expand during 1980. The greatest concentration of activity was in Nigeria. However, there was considerable increase in the level of exploratory work in Cameroon and Congo. Significant new finds have been made in Ivory Coast. Geological and geophysical activity was carried out in 18 of the countries, with those in the western part having the largest share. Seismic work involved 225 party months of operation. Most of this time was spent on land, but marine operations accounted for 73,389 km of new control. Gravity and magnetic data were recorded during the marine surveys, and several large aeromagnetic projects were undertaken to obtain a total of 164,498 line km of data. Exploratory and development drilling accounted for a total of 304 wells and 2,605,044 ft (794,212 m) of hole. The 92 exploratory wells that were drilled resulted in 47 oil and gas discoveries. In development drilling 89% of the 212 wells were successful. At the end of the year, 27 exploratory wells were underway, and 34 development wells were being drilled for a total of 61. Oil production from the countries that this review covers was 918,747,009 bbl in 1980, a drop of about 9% from the previous year. Countries showing a decline in production were Nigeria, Gabon, Cabinda, and Zaire. Increases were recorded in Cameroon, Congo, and Ghana. A new country was added to the list of producers when production from the Belier field in Ivory Coast came on stream. 33 figures, 15 tables.

McGrew, H.J.



On the variability of alligator sex ratios  

USGS Publications Warehouse

Samples of alligators from wild and 'farm' populations exhibited disproportionate sex ratios. Males predominated among young alligators from wild populations, whereas females were much more abundant than males in the farm population, where resources were superabundant. These results and other considerations lead us to hypothesize that environmental factors influence sex determination in alligators. During favorable environmental conditions natural selection is expected to favor a preponderance of the sex whose individuals exhibit the greater environmentally associated variation in relative fitness. We hypothesize that environmentally associated variation in age at sexual maturity of females produces sufficient variation in relative fitness of females to result in selection for low sex ratios during periods of resource abundance.

Nichols, J.D.; Chabreck, R.H.



Secular trends in newborn sex ratios.  


A wide variety of factors have been shown to influence the male to female ratio at birth, which invariably displays a male excess. This paper will review and amplify recent work by the author, with specific references to individual countries, regions and entire continents in order to provide a global overview of this subject. It will be shown that stress, including stress related to political events, influences this ratio. Man-made radiation is also shown to have played a significant role in relation to the Windscale fire (1957) and Chernobyl (1986). PMID:25219502

Grech, Victor



Radioactive anomaly discrimination from spectral ratios  


A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.

Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements



Prevalence of Low Birth Weight and Obesity in Central Iran  

ERIC Educational Resources Information Center

To estimate the prevalence of low birth weight (LBW) and to document distribution of body mass index (BMI) at birth in Arak (central Iran) neonates of the 10,241 live neonates (5241 boys, 5000 girls, sex ratio 105) born in 2004 in Arak. A birth weight of less than 2500 g was classified as LBW. BMI based on the original supine length and weight…

Rafiei, M.; Ayatollahi, S. M. T.



The isotopic composition of strontium in central American ignimbrites  

Microsoft Academic Search

Voluminous sheets of rhyolitic ignimbrites were crupted during Miocene time in a region of Central America that is underlain\\u000a by a thick sequence of middle Paleozoic and older metamorphic and plutonic rocks. Strontium isotopic ratios of fifteen ignimbrites\\u000a range from 0.7035 to as high as 0.7175. These values are markedly higher than those measured for cale-alkaline lavas of the\\u000a same

P. Pushkar; A. R. McBirney; A. M. Kudo



The Period-Ratio and Mass-Ratio Correlation in Extra-Solar Multiple Planetary Systems  

E-print Network

Employing the data from orbital periods and masses of extra-solar planets in 166 multiple planetary systems, the period-ratio and mass-ratio of adjacent planet pairs are studied. The correlation between the period-ratio and mass-ratio is confirmed and found to have a correlation coefficient of 0.5303 with a 99% confidence interval (0.3807, 0.6528). A comparison with the distribution of synthetic samples from a Monte Carlo simulation reveals the imprint of planet-planet interactions on the formation of adjacent planet pairs in multiple planetary systems.

Jiang, Ing-Guey; Hung, Wen-Liang



Mantel-Haenszel odds ratio and Peto's log odds ratio under the general framework of combining CDs  

E-print Network

Mantel-Haenszel odds ratio and Peto's log odds ratio under the general framework of combining CDs ratio is a special case of combining aCDs and Peto's log odds ratio can also be derived using(1 - p1) . · Objects of interest: odds ratio , log odds ratio = ln . 2. Mantel-Haenszel and Peto methods

Xie, Minge


Efficiency Ratios and Community Bank Performance  

Microsoft Academic Search

This study develops a multivariate discriminant model to differentiate between low efficiency and high efficiency community banks (less than $1 billion in total assets) based upon the efficiency ratio, a commonly used financial performance measure that relates non-interest expenses to total operating income. The model includes proxies for the banking regulatory CAMELS rating variables including: the equity capital to total

Fred H. Hays; Arthur H. Gilbert


Flowmeter determines mix ratio for viscous adhesives  

NASA Technical Reports Server (NTRS)

Flowmeter determines mix ratio for continuous flow mixing machine used to produce an adhesive from a high viscosity resin and aliphatic amine hardener pumped through separate lines to a rotary blender. The flowmeter uses strain gages in the two flow paths and monitors their outputs with appropriate instrumentation.

Lemons, C. R.



Ratios exaggerate gender differences in mathematical ability  

Microsoft Academic Search

Comments on J. C. Stanley and C. P. Benbow's assertion concerning gender differences in the distribution of SAT-M scores. The present author contends that if an emphasis on group differences minimizes the magnitude of gender differences, then an emphasis on ratio can only exaggerate such differences.

Joseph S. Rossi



Do Credit Spreads Reflect Stationary Leverage Ratios?  

Microsoft Academic Search

Most structural models of default preclude the firm from altering its capital structure. In practice, firms adjust outstanding debt levels in response to changes in firm value, thus generating mean-reverting leverage ratios. We propose a structural model of default with stochastic interest rates that captures this mean reversion. Our model generates credit spreads that are larger for low-leverage firms, and

Pierre Collin-Dufresne; Robert S. Goldstein



Preprocessing Text to Improve Compression Ratios  

Microsoft Academic Search

Summary form only given. We discuss the use of a text preprocessing algorithm that can improve the compression ratio of standard data compression algorithms, in particular `bzip2', when used on text files, by up to 20%. The text preprocessing algorithm uses a static dictionary of the English language that is kept separately from the compressed file. The method in which

Holger Kruse; Amar Mukherjee



Compression ratio effect on methane HCCI combustion  

SciTech Connect

The authors have used the HCT (hydrodynamics, chemistry, and transport) chemical kinetics code to simulate HCCI (homogeneous charge compression ignition) combustion of methane-air mixtures. HCT is applied to explore the ignition timing, burn duration, NO{sub X}production, gross indicated efficiency and gross IMEP of a supercharged engine (3 atm. intake pressure) with 14:1, 16:1 and 18:1 compression ratios at 1200 rpm. HCT has been modified to incorporate the effect of heat transfer and to calculate the temperature that results from mixing the recycled exhaust with the fresh mixture. This study uses a single reaction zone that varies as a function of crank angle. The ignition process is controlled by adjusting the intake equivalence ratio and the residual gas trapping (RGT). RGT is internal exhaust gas recirculation, which recycles both thermal energy and combustion product species. Adjustment of equivalence ratio and RGT is accomplished by varying the timing of the exhaust valve closure in either two-stroke or four-stroke engines. Inlet manifold temperature is held constant at 300 K. Results show that, for each compression ratio, there is a range of operational conditions that show promise of achieving the control necessary to vary power output while keeping indicated efficiency above 50 percent and NO{sub X}levels below 100 ppm. HCT results are also compared with a set of recent experimental data for natural gas.

Aceves, S.M.; Smith, J.R.; Westbrook, C.K.; Pitz, W.J. [Lawrence Livermore National Lab., CA (United States)



Compression ratio effect on methane HCCI combustion  

SciTech Connect

We have used the HCT (Hydrodynamics, Chemistry and Transport) chemical kinetics code to simulate HCCI (homogeneous charge compression ignition) combustion of methane-air mixtures. HCT is applied to explore the ignition timing, bum duration, NOx production, gross indicated efficiency and gross IMEP of a supercharged engine (3 atm. Intake pressure) with 14:1, 16:l and 18:1 compression ratios at 1200 rpm. HCT has been modified to incorporate the effect of heat transfer and to calculate the temperature that results from mixing the recycled exhaust with the fresh mixture. This study uses a single control volume reaction zone that varies as a function of crank angle. The ignition process is controlled by adjusting the intake equivalence ratio and the residual gas trapping (RGT). RGT is internal exhaust gas recirculation which recycles both thermal energy and combustion product species. Adjustment of equivalence ratio and RGT is accomplished by varying the timing of the exhaust valve closure in either 2-stroke or 4-stroke engines. Inlet manifold temperature is held constant at 300 K. Results show that, for each compression ratio, there is a range of operational conditions that show promise of achieving the control necessary to vary power output while keeping indicated efficiency above 50% and NOx levels below 100 ppm. HCT results are also compared with a set of recent experimental data for natural gas.

Aceves, S. M.; Pitz, W.; Smith, J. R.; Westbrook, C.



Meteorological Effects on Air/Fuel Ratio  

E-print Network

in humidity directly affect the volume percentage of oxygen. Since most ratio systems are unaware of changes in oxygen content of the air, the preset excess air rate will vary. This paper quantifies these variations and the method of calculation for any...

Ferri, J. L.



Disproportionate sex ratios of wolf pups  

USGS Publications Warehouse

Males comprised 66 percent of wild wolf (Canis lupus) pups from a saturated, high-density wolf range in northeastern Minnesota, possibly reflecting disproportionate conception of males. Packs from areas of lower wolf density in other areas of Minnesota had equal sex ratios of pups or a disproportionate number of female pups. Captive wolves showed a slight preponderance of male pups.

Mech, L.D.



Thin solar concentrator with high concentration ratio  

NASA Astrophysics Data System (ADS)

Solar concentrators are often used in conjunction with III-V multi-junction solar cells for cost reduction and efficiency improvement purposes. High flux concentration ratio, high optical efficiency and high manufacture tolerance are the key features required for a successful solar concentrator design. This paper describes a novel solar concentrator that combines the concepts, and thus the advantages, of both the refractive type ad reflective type. The proposed concentrator design adopts the Etendue-cascading concept that allows the light beams from all the concentric annular entrance pupils to be collected and transferred to the solar cell with minimal loss. This concept enables the system to perform near its Etendue-Limit and have a high concentration ratio simultaneously. Thereby reducing the costs of solar cells and therefor achieves a better the per watts cost. The concentrator demonstrated has a thing aspect ratio of 0.19 with a zero back focal distance. The numerical aperture at the solar cell immersed inside the dielectric concentrator is as high as 1.33 achieving a unprecedented high optical concentration ratio design.

Lin, Jhe-Syuan; Liang, Chao-Wen



Measuring Isotope Ratios Across the Solar System  

NASA Technical Reports Server (NTRS)

Stable isotope ratios in C, H, N, O and S are powerful indicators of a wide variety of planetary geophysical processes that can identify origin, transport, temperature history, radiation exposure, atmospheric escape, environmental habitability and biology [1]. For the Allan Hills 84001 meteorite, for example, the (sup 1)(sup 3)C/(sup 1)(sup 2)C ratio identifies it as a Mars (SNC) meteorite; the ??K/??Ar ratio tells us the last time the rock cooled to solid, namely 4 Gya; isotope ratios in (sup 3)He, (sup 2)(sup 1)Ne and (sup 3)?Ar show it was in space (cosmic ray exposure) for 10-20 million years; (sup 1)?C dating that it sat in Antarctica for 13,000 years before discovery; and clumped isotope analysis of (sup 1)?O(sup 1)(sup 3)C(sup 1)?O in its carbonate that it was formed at 18+/-4 ?C in a near-surface aqueous environment [2]. Solar System Formation

Webster, Chris R.; Mahaffy, Paul R.



Gyromagnetic ratio of a black hole  

Microsoft Academic Search

We examine the properties of a rotating loop of charged matter in the presence of a static charged black hole. The behavior of the gyromagnetic ratio is examined in the limit as the radius of the loop becomes very large and in the limit as the loop radius approaches the radius of the black hole's event horizon. The implications of

David Garfinkle; Jennie Traschen



Viscosity to entropy ratio at extremality  

E-print Network

Assuming gauge theory realization at the boundary, we show that the viscosity to entropy ratio is 1/(4 pi) where the bulk is represented by a large class of extremal black holes in anti-de Sitter space. In particular, this class includes multiple R-charged black holes in various dimensions.

Sayan K. Chakrabarti; Sachin Jain; Sudipta Mukherji



Ratio control system for continuously variable transmission  

SciTech Connect

This patent describes a ratio control system for a continuously variable transmission which performs a feedback control wherein an integral control gain and a proportional control gain are varied depending upon the level of a line pressure that is used to actuate a pulley unit during shifting operation.

Oshiage, K.



Female-predominant sex ratios in angiosperms  

Microsoft Academic Search

A model is presented which expresses the seed production of dioecious and gynodioecious animal-pollinated Angiosperms in terms of the relative seed-fecundity of the sexes, the number of pollinator visits to each flower and the sex ratio. The model predicts that the maximum seed set occurs when females predominate, providing the pollinators visit each flower more than once and the seed

David G Lloyd



Giving More Realistic Definitions of Trigonometric Ratios  

ERIC Educational Resources Information Center

Trigonometry is a well known branch of Mathematics. The study of trigonometry is of great importance in surveying, astronomy, navigation, engineering, and in different branches of science. This paper reports on the discovery of flaws in the traditional definitions of trigonometric ratios of an angle, which (in most cases) make use of the most…

Bhattacharjee, Pramode Ranjan



North Central Thailand  

NASA Technical Reports Server (NTRS)

This radar image shows the dramatic landscape in the Phang Hoei Range of north central Thailand, about 40 kilometers (25 miles) northeast of the city of Lom Sak. The plateau, shown in green to the left of center, is the area of Phu Kradung National Park. This plateau is a remnant of a once larger plateau, another portion of which is seen along the right side of the image. The plateaus have been dissected by water erosion over thousands of years. Forest areas appear green on the image; agricultural areas and settlements appear as red and blue. North is toward the lower right. The area shown is 38 by 50 kilometers (24 by 31 miles) and is centered at 16.96 degrees north latitude, 101.67 degrees east longitude. Colors are assigned to different radar frequencies and polarizations as follows: red is L-band horizontally transmitted and horizontally received; green is L-band horizontally transmitted and vertically received; blue is C-band horizontally transmitted and vertically received. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture (SIR-C/X-SAR) imaging radar on October 3, 1994, when it flew aboard the space shuttle Endeavour. SIR-C/X-SAR is a joint mission of the U.S./German and Italian space agencies.

Spaceborne Imaging Radar-C and X-Band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community to better understand the global environment and how it is changing. The SIR-C/X-SAR data, complemented by aircraft and ground studies, will give scientists clearer insights into those environmental changes which are caused by nature and those changes which are induced by human activity. SIR-C was developed by NASA's Jet Propulsion Laboratory. X-SAR was developed by the Dornier and Alenia Spazio companies for the German space agency, Deutsche Agentur fuer Raumfahrtangelegenheiten (DARA), and the Italian space agency, Agenzia Spaziale Italiana (ASI), with the Deutsche Forschungsanstalt fuer Luft und Raumfahrt e.v.(DLR), the major partner in science, operations, and data processing of X-SAR.



Optical Quality in Central Serous Chorioretinopathy.  


Purpose:To assess optical quality and intraocular scattering using the Optical Quality Analysis System (OQAS®; Visiometrics, Terrassa, Spain) in central serous chorioretinopathy (CSC), and determine the effects of retinal changes on optical quality. Methods:The study was prospective and case-controlled. Participants were 29 patients with diagnosed CSC. The control group consisted of the patients' unaffected eyes. Initial log MAR visual acuity, central macular thickness by spectral domain optic coherence tomography (SD-OCT), and optical quality parameters including modulation transfer function cutoff frequency (MTF cutoff), Strehl (2D) ratio, and OQAS® values (OV) at 100%, 20%, and 9% contrasts were investigated. Objective scatter index (OSI) at 4.0 mm pupil size was assessed in both eyes, via the OQAS®. After 3 months of treatment, including observation and focal laser or anti-vascular endothelial growth factor (VEGF) injection, every CSC-affected eye was followed up. The main outcome measures were differences in clinical parameters between the CSC-affected eye and control eye, and changes in those parameters according to the natural history of CSC over 3 months. Results:In CSC-affected eyes, the MTF cutoff was significantly reduced (p = 0.01) and OSI was significantly increased (p = 0.03). As macular thickness decreased, OSI decreased, but did not become normalized as compared to the control eye, nor was it statistically significantly correlated with central macular thickness change. Conclusions:Retinal change affected optical quality and intraocular scatter. Therefore, when the severity of a cataract is assessed using the OQAS®, retinal status should be considered when interpreting the OQAS® values. PMID:25468888

Lee, Kyungmin; Sohn, Joonhong; Choi, Jong Gil; Chung, Sung Kun



Glycosaminoglycans of the porcine central nervous system†  

PubMed Central

Glycosaminoglycans (GAG) are known to participate in central nervous system processes such as development, cell migration, and neurite outgrowth. In this paper, we report an initial glycomics study on GAGs from porcine central nervous system. GAGs of the porcine central nervous system, brain and spinal cord, were isolated and purified by defating, proteolysis, anion-exchange chromatography and methanol precipitation. The isolated GAG content in brain was 5-times higher than in spinal cord (0.35 mg/g, compared to 0.07 mg/g dry sample). In both tissues, chondroitin sulfate (CS) and heparan sulfate (HS) were the major and the minor GAG. The average molecular weight of CS from brain and spinal cord was 35.5 and 47.1 kDa, respectively, and HS from brain and spinal cord was 56.9 and 34 kDa, respectively. The disaccharide analysis showed that the composition of CS from brain and spinal cords are similar with uronic acid (1?3) 4-O-sulfo-N-acetylgalactosamine residue corresponding to the major disaccharide unit (CS type-A) along with five minor disaccharide units. The major disaccharides of both brain and spinal cord HS were uronic acid (1?4) N-acetylglucosamine and uronic acid (1?4) 6-O-sulfo-N-sulfoglucosamine but their composition of minor disaccharides differed. Analysis by 1H- and two-dimensional-NMR spectroscopy confirmed these disaccharide analyses and provided the glucuronic/iduronic acid ratio. Finally, both purified CS and HS were biotinylated and immobilized on BIAcore SA biochips. Interactions between these GAGs and fibroblast growth factors (FGF1 and FGF2) and sonic hedgehog (Shh) were investigated by surface plasmon resonance. PMID:20954748

Liu, Zhenling; Masuko, Sayaka; Solakyildirim, Kemal; Pu, Dennis; Linhardt, Robert J.; Zhang, Fuming



Focal ratio degradation in lightly fused hexabundles  

NASA Astrophysics Data System (ADS)

We are now moving into an era where multi-object wide-field surveys, which traditionally use single fibres to observe many targets simultaneously, can exploit compact integral field units (IFUs) in place of single fibres. Current multi-object integral field instruments such as Sydney-AAO Multi-object Integral field spectrograph have driven the development of new imaging fibre bundles (hexabundles) for multi-object spectrographs. We have characterized the performance of hexabundles with different cladding thicknesses and compared them to that of the same type of bare fibre, across the range of fill fractions and input f-ratios likely in an IFU instrument. Hexabundles with 7-cores and 61-cores were tested for focal ratio degradation (FRD), throughput and cross-talk when fed with inputs from F/3.4 to >F/8. The five 7-core bundles have cladding thickness ranging from 1 to 8 ?m, and the 61-core bundles have 5 ?m cladding. As expected, the FRD improves as the input focal ratio decreases. We find that the FRD and throughput of the cores in the hexabundles match the performance of single fibres of the same material at low input f-ratios. The performance results presented can be used to set a limit on the f-ratio of a system based on the maximum loss allowable for a planned instrument. Our results confirm that hexabundles are a successful alternative for fibre imaging devices for multi-object spectroscopy on wide-field telescopes and have prompted further development of hexabundle designs with hexagonal packing and square cores.

Bryant, J. J.; Bland-Hawthorn, J.; Fogarty, L. M. R.; Lawrence, J. S.; Croom, S. M.



Combined central and peripheral demyelination  

PubMed Central

Acquired central and peripheral demyelination in the same patient is a very rare feature. We report a 52-year-male patient with the chronic autoimmune hepatitis (CAH) presenting with pure motor areflexic quadriparesis from 4 months and recent onset of drowsiness of 4 days duration. Studies of imaging and electrophysiology suggested central pontine myelinolysis and chronic inflammatory demyelinating polyradiculoneuropathy. Patient was effectively treated with high dose steroids. To the best of our knowledge, this is the first case of central and peripheral demyelination in a patient with CAH. PMID:24741261

Menon, Bindu; Bedi, Saranjeet Singh; Rao, G. Uma Maheshwar



CASWW Central Asia Experts Directory  

NSDL National Science Digital Library

Provided by the Harvard Forum for Central Asian Studies, this site will prove useful to graduate students and scholars of Central Asia. The site was created to facilitate access for policy-makers, the press, and others to scholars with the appropriate expertise in Central Asian Studies. The Directory features those who have indicated their willingness to be contacted for expert consultations, and their listing will include a brief description of their qualifications. It organizes experts by name, topic, location, and under several headings: Politics and International Relations, Economy, Social Issues, and Cultural and Historical Background. The site is still soliciting experts for inclusion, and a link to the questionnaire is provided.


SIZE RATIOS The analysis of size ratios of coexisting species has been a major focus in  

E-print Network

for character displace- ment comes from studies of birds (Diamond et al. 1989),lizards (Losos 1990), fish) suggested that body size differ- ences among predators should evolve to reduce the effects of competition ratios of several pairs of sympatric bird and mammal species ranged from 1.1 to 1.4. The mean ratio

Gotelli, Nicholas J.


Study on Corporate Hereditary Central Dogma  

Microsoft Academic Search

Based on analyzing the central dogma of biology, this paper raises hypothesis, using the analogism method to set up the corporate hereditary central dogma. It analyzes the differences between the Corporate hereditary central dogma and the central dogma of biology, which explains the significance of research on Corporate hereditary central dogma; it discusses the meanings of all factors of Corporate

Li Xianbai



CFD assessment of orifice aspect ratio and mass flow ratio on jet mixing in rectangular ducts  

NASA Technical Reports Server (NTRS)

Isothermal CFD analysis was performed on axially opposed rows of jets mixing with cross flow in a rectangular duct. Laterally, the jets' centerlines were aligned with each other on the top and bottom walls. The focus of this study was to characterize the effects of orifice aspect ratio and jet-to-mainstream mass flow ratio on jet penetration and mixing. Orifice aspect ratios (L/W) of 4-to-1, 2-to-1, and 1-to-1, along with circular holes, were parametrically analyzed. Likewise, jet-to-mainstream mass flow ratios (MR) of 2.0, 0.5, and 0.25 were systematically investigated. The jet-to-mainstream momentum-flux ratio (J) was maintained at 36 for all cases, and the orifice spacing-to-duct height (S/H) was varied until optimum mixing was attained for each configuration. The numerical results showed that orifice aspect ratio (and likewise orifice blockage) had little effect on jet penetration and mixing. Based on mixing characteristics alone, the 4-to-1 slot was comparable to the circular orifice. The 4-to-1 slot has a smaller jet wake which may be advantageous for reducing emissions. However, the axial length of a 4-to-1 slot may be prohibitively long for practical application, especially for MR of 2.0. The jet-to-mainstream mass flow ratio had a more significant effect on jet penetration and mixing. For a 4-to-1 aspect ratio orifice, the design correlating parameter for optimum mixing (C = (S/H)(sq. root J)) varied from 2.25 for a mass flow ratio of 2.0 to 1.5 for a mass flow ratio of 0.25.

Bain, D. B.; Smith, C. E.; Holdeman, J. D.




SciTech Connect

When routine sampling revealed greatly elevated tritium levels (3.14 x 105 Bq/L [8.5-million pCi/liter]) in the groundwater near a solid waste landfill at the Hanford Site, an innovative technique was used to assess the extent of the plume. Helium-3/helium-4 ratios, relative to ambient air-in-soil gas samples, were used to identify the tritium source and initially delineate the extent of the groundwater tritium plume. This approach is a modification of a technique developed in the late 1960s to age-date deep ocean water as part of the GEOSECS ocean monitoring program. Poreda, et al. (1) and Schlosser, et al. (2) applied this modified technique to shallow aquifers. A study was also conducted to demonstrate the concept of using helium-3 as a tool to locate vadose zone sources of tritium and tracking groundwater tritium plumes at Hanford (3). Seventy sampling points were installed around the perimeter and along four transects downgradient of the burial ground. Soil gas samples were collected, analyzed for helium isotopes, and helium-3/helium-4 ratios were calculated for these 70 points. The helium ratios indicated a vadose zone source of tritium along the northern edge of the burial ground that is likely the source of tritium in the groundwater. The helium ratios also indicate the groundwater plume is traveling east-northeast from the burial ground and that no up-gradient tritium sources are affecting the burial ground. Based on the helium ratio results, six downgradient groundwater sampling locations were identified to verify the tritium plume extent and groundwater tritium concentrations. The tritium results from the initial groundwater samples confirmed that elevated helium ratios were indicative of tritium contamination in the local groundwater. The measurement of helium isotopes in soil gas provided a rapid and cost- effective technique to define the shape and extent of tritium contamination from the burial ground. Using this soil gas sampling approach, the project team was able to identify areas where elevated tritium existed in groundwater without going to the time and expense of conducting conventional groundwater characterization sampling. The savings from this characterization approach were $1.4 million.

Ovink, R.W.; McMahon, W.J.; Borghese, J.V.; Olsen, K.B.



High Hypopnea/Apnea Ratio (HAR) in Extreme Obesity  

PubMed Central

Study Objectives: The study was performed to evaluate the hypothesis that the extremely obese manifest sleep disordered breathing with a preponderance of hypopneas and relative paucity of obstructive apneas. Methods: Retrospective review of 90 adults with obstructive sleep apnea-hypopnea syndrome (OSAHS) matched for age and gender, comparing two groups, Group A: body mass index (BMI) < 35, Group B: BMI ? 45. Exclusion criteria: age < 18 years, pregnancy, ? 5 central apneas/hour, BMI ? 35 < 45. Primary Outcome Measure: Hypopnea/apnea ratio (HAR); secondary measures: obstructive apnea-hypopnea index (AHI), obstructive and central apnea indices, hypopnea index (HI), oxygen saturation (SpO2) nadir, end-tidal carbon dioxide tension (PetCO2), and presence of obesity-hypoventilation syndrome (OHS). Statistical methods: t-test for independent samples; Mann-Whitney, linear regression with natural log transformation, and Kruskal-Wallis ?2. Descriptive statistics were expressed as interquartile range, median and mean ± standard deviation, p < 0.05 considered significant. Results: Group A (n = 45): age = 50.6 ± 11.5 years, BMI = 28.9 ± 4 kg/m2; Group B (n = 45): age = 47.4 ± 12.7 years, BMI = 54.5 ± 8 kg/m2. HAR was significantly higher in Group B (38.8 ± 50.7) than Group A (10.6 ± 16.5), p = 0.0006, as was HI (28.7 ± 28.6 in B vs 12.6 ± 8.4 in A, p = 0.0005) and AHI (35.5 ± 33.8 vs 22 ± 23, p = 0.03), but not apnea index. HAR was significantly higher in Group B regardless of race, gender, or presence of OHS. The BMI was the only significant predictor of HAR (adjusted r2 = 0.138; p = 0.002) in a linear regression model with natural log transformation of the HAR performed for age, gender, race, BMI, and PetCO2. Conclusion: Extremely obese patients manifest OSAHS with a preponderance of hypopneas. Citation: Mathew R; Castriotta RJ. High hypopnea/apnea ratio (HAR) in extreme obesity. J Clin Sleep Med 2014;10(4):391-396. PMID:24733984

Mathew, Reeba; Castriotta, Richard J.



Arnold Schwarzenegger THE CENTRAL CALIFORNIA  

E-print Network

Arnold Schwarzenegger Governor THE CENTRAL CALIFORNIA OZONE STUDY Prepared For: California Energy Commission Public Interest Energy Research Program Prepared By: California Air Resources Board Planning and Technical Support Division California Air Resources Board California Environmental Protection


Super Kitchen Centralizes Food Service  

ERIC Educational Resources Information Center

To centralize food service within the entire Pittsburgh school district, a 90,000-square-foot food service preparation building contains cranes and monorails to move 500-pound capacity vats throughout the kitchen. (Author/MLF)

Modern Schools, 1975



Central Dogma of Molecular Biology  

Microsoft Academic Search

The central dogma of molecular biology deals with the detailed residue-by-residue transfer of sequential information. It states that such information cannot be transferred from protein to either protein or nucleic acid.

Francis Crick



Pricing Central Tendency in Volatility  

E-print Network

It is widely accepted that there is a risk of fluctuating volatility. There is some evidence, analogously to long-term consumption risk literature or central tendency in interest rates, that there exists a slowly varying component in volatility. Volatility literature concentrates on investigation of two-factor volatility process, with one factor being very persistent. I propose a different parametrization of volatility process that includes this persistent component as a stochastic central tendency. The reparametrization is observationally equivalent but has compelling economic interpretation. I estimate the historical and riskneutral parameters of the model jointly using GMM with the data on realized volatility and VIX volatility index and treating central tendency as completely unobservable. The main result of the paper is that on average the volatility premium is indistinguishable from the premium on highly persistent shocks of the central tendency.

Stanislav Khrapov



Gyromagnetic ratio of a massive body.  

NASA Technical Reports Server (NTRS)

It is well known that the gyromagnetic ratio (g factor) of a classical, slowly rotating body whose charge density is proportional to its mass density must be equal to unity. However, if the body is very massive, the spacetime curvature effects of general relativity become important and the result g = 1 is no longer valid. We calculate here the gyromagnetic ratio of a slowly rotating, massive shell with uniform charge density. When the shell is large compared with the Schwarzschild radius we have g = 1, but as the shell becomes more massive the g factor increases. In the limit as the shell approaches its Schwarzschild radius we obtain g approaching 2 (the same value as for an electron).

Cohen, J. M.; Tiomno, J.; Wald, R. M.



The basic reproductive ratio of life  

PubMed Central

Template-directed polymerization of nucleotides is believed to be a pathway for the replication of genetic material in the earliest cells. We assume that activated monomers are produced by prebiotic chemistry. These monomers can undergo spontaneous polymerization, a system that we call “prelife.” Adding template-directed polymerization changes the equilibrium structure of prelife if the rate constants meet certain criteria. In particular, if the basic reproductive ratio of sequences of a certain length exceeds one, then those sequences can attain high abundance. Furthermore, if many sequences replicate, then the longest sequences can reach high abundance even if the basic reproductive ratios of all sequences are less than one. We call this phenomenon “subcritical life.” Subcritical life suggests that sequences long enough to be ribozymes can become abundant even if replication is relatively inefficient. Our work on the evolution of replication has interesting parallels to infection dynamics. Life (replication) can be seen as an infection of prelife. PMID:20034501

Manapat, Michael L.; Chen, Irene A.; Nowak, Martin A.



Sr / Ca and Mg / Ca ratios in polygenetic carbonate allochems from a Michigan marl lake  

NASA Astrophysics Data System (ADS)

Rapid accumulation of CaCO 3 is occurring in Littlefield Lake, a marl lake located in central Michigan. The sediment, which is 95% CaCO 3, primarily consists of eight different genetic groups of carbonate allochems. These include calcite muds, sands, algal oncoids and Chara encrustations, as well as the dominant aragonitic gastropods Valvota tricarinota. Gyraulus deflectus and Amnicola integra. and the dominant aragonitic pelecypod Sphaerium partumeium. Samples of each of these groups were analyzed for Ca, Sr and Mg. Molar Mg/Ca ratios are primarily controlled by allochem mineralogy, with calcitic forms having Mg/Ca ratios 5-10 times larger than aragonitic (shelled) forms. The Sr/Ca ratios are primarily controlled by biochemical fractionation, and are significantly lower than Sr/Ca ratios of inorganically precipitated aragonite from other settings. Partition coefficients were determined for both Sr and Mg for each carbonate allochem group and, based on comparisons with results reported by other workers, the partition coefficients determined here are generally considered 'typical' or representative values for biogeneous freshwater carbonates. An analysis of variance of the data indicates that most genera and species of carbonate-secreting organisms in marl lakes have highly characteristic Sr/Ca and Mg/Ca ratios. These ratios can potentially serve as geochemical tracers in future investigations of lacustrine carbonate diagenesis. Both Sr and Mg are influenced by grain size and/or surface area, probably due to the presence of these elements in non-lattice-held (exchangeable) positions.

Treese, Thomas N.; Owen, Robert M.; Wilkinson, Bruce H.



Microbial respiration per unit microbial biomass depends on soil litter carbon-to-nitrogen ratio  

NASA Astrophysics Data System (ADS)

Soil microbial respiration is a central process in the terrestrial carbon (C) cycle. In this study I tested the effect of the carbon-to-nitrogen (C : N) ratio of soil litter layers on microbial respiration in absolute terms and per unit microbial biomass C. For this purpose, a global dataset on microbial respiration per unit microbial biomass C - termed the metabolic quotient (qCO2) - was compiled form literature data. It was found that the qCO2 in the soil litter layers was positively correlated with the litter C : N ratio and negatively related with the litter nitrogen (N) concentration. The positive relation between qCO2 and litter C : N ratio resulted from an increase in respiration with the C : N ratio in combination with no significant effect of the litter C : N ratio on the soil microbial biomass C concentration. The results suggest that soil microorganisms respire more C both in absolute terms and per unit microbial biomass C when decomposing N-poor substrate. Thus, the findings indicate that atmospheric N deposition, leading to decreased litter C : N ratios, might decrease microbial respiration in soils.

Spohn, M.



Co-composting of green waste and food waste at low C/N ratio  

SciTech Connect

In this study, co-composting of food waste and green waste at low initial carbon to nitrogen (C/N) ratios was investigated using an in-vessel lab-scale composting reactor. The central composite design (CCD) and response surface method (RSM) were applied to obtain the optimal operating conditions over a range of preselected moisture contents (45-75%) and C/N ratios (13.9-19.6). The results indicate that the optimal moisture content for co-composting of food waste and green waste is 60%, and the substrate at a C/N ratio of 19.6 can be decomposed effectively to reduce 33% of total volatile solids (TVS) in 12 days. The TVS reduction can be modeled by using a second-order equation with a good fit. In addition, the compost passes the standard germination index of white radish seed indicating that it can be used as soil amendment.

Kumar, Mathava; Ou, Y.-L. [Institute of Environmental Engineering, National Chiao Tung University, 1001, University Road, Hsinchu City 30010, Taiwan (China); Lin, J.-G., E-mail: [Institute of Environmental Engineering, National Chiao Tung University, 1001, University Road, Hsinchu City 30010, Taiwan (China)



Sodium\\/Potassium Ratio in Rainwater  

Microsoft Academic Search

DR. B. C. V. ODDIE has commented1 on a portion of my recent article ``Surface of the Ocean as a Source of Air-Borne Nitrogenous Material and Other Plant Nutrients''2 with particular reference to the sodium\\/potassium ratio in rain-water. In this article I presented results of the analysis of New Zealand snows and proposed that there exists on the surface of

A. T. Wilson



Compression ratio effect on methane HCCI combustion  

Microsoft Academic Search

The authors have used the HCT (hydrodynamics, chemistry, and transport) chemical kinetics code to simulate HCCI (homogeneous charge compression ignition) combustion of methane-air mixtures. HCT is applied to explore the ignition timing, burn duration, NO{sub X}production, gross indicated efficiency and gross IMEP of a supercharged engine (3 atm. intake pressure) with 14:1, 16:1 and 18:1 compression ratios at 1200 rpm.

S. M. Aceves; J. R. Smith; C. K. Westbrook; W. J. Pitz



Compression ratio effect on methane HCCI combustion  

Microsoft Academic Search

We have used the HCT (Hydrodynamics, Chemistry and Transport) chemical kinetics code to simulate HCCI (homogeneous charge compression ignition) combustion of methane-air mixtures. HCT is applied to explore the ignition timing, bum duration, NOx<\\/sub> production, gross indicated efficiency and gross IMEP of a supercharged engine (3 atm. Intake pressure) with 14:1, 16:l and 18:1 compression ratios at 1200 rpm. HCT

S. M. Aceves; W. Pitz; J. R. Smith; C. Westbrook



Determination of 241 Am\\/ 243 Am ratios  

Microsoft Academic Search

Determination of 241Am\\/243Am ratios is required for vanous purposes including assay of Am by isotope dilution techniques. Alpha-spectrometry on electrodeposited\\u000a sources is a preferred technique for this determination. However, there is an inherent problem of tail contribution which\\u000a necessitates the use of suitable algorithms to account for the same. Recently, in the frame of a Coordinated Research Program\\u000a (CRP) of

S. K. Aggarwal; D. Alamelu; P. M. Shah; N. N. Mirashi



A modulated shear to entropy ratio  

NASA Astrophysics Data System (ADS)

We study correlation functions in an equilibrated spatially modulated phase of Einstein-Maxwell two-derivative gravity. We find that the ratio of the appropriate low frequency limit of the stress-stress two point function to the entropy density is modulated. The conductivity, the stress-current and current-stress correlation functions are also modulated. At temperatures close to the phase transition we obtain analytic expressions for some of the correlation functions.

Ovdat, O.; Yarom, A.



Collective gyromagnetic ratios of deformed nuclei  

Microsoft Academic Search

The effective gyromagnetic ratios of the ground-state rotational band in deformed nuclei have been calculated on the basis of the cranking model formula. The latter has been evaluated in terms of deformed shell-model wave functions with inclusion of pair correlations. Comparison with experimental data both as to doubly even and odd-mass nuclei shows in general very good agreement within a

O. Prior; F. Boehm; S. G. Nilsson



Polyatomic ions, branching ratios and hot molecules  

NASA Astrophysics Data System (ADS)

A discussion is given of the reason for the sharp fall-off observed in Dissociative Recombination (DR) cross sections above about 0.1 eV and of the need for accurate branching ratios being used in complex models of molecular ion chemistry. New measurements from TSR have shown that stored ions are not as cold as they were once thought to be and a new experiment facility is presented.

Mitchell, J. Brian A.



The golden ratio in special relativity  

Microsoft Academic Search

In this note we show that Euclid’s construction of the golden rectangle can be used to derive both the dilation of time intervals and the Lorentz contraction of lengths as predicted by Einstein’s theory of special relativity. In this simple exercise, the Lorentz factor arises as a direct consequence of the Pythagorean theorem, while the golden ratio, ?=1+5\\/2, is found

Leonardo Di G. Sigalotti; Antonio Mejias



Ductile Titanium Alloy with Low Poisson's Ratio  

Microsoft Academic Search

We report a ductile β-type titanium alloy with body-centered cubic (bcc) crystal structure having a low Poisson's ratio of 0.14. The almost identical ultralow bulk and shear moduli of â24 GPa combined with an ultrahigh strength of â0.9 GPa contribute to easy crystal distortion due to much-weakened chemical bonding of atoms in the crystal, leading to significant elastic softening in

Y. L. Hao; S. J. Li; B. B. Sun; M. L. Sui; R. Yang



Ductile Titanium Alloy with Low Poisson's Ratio  

Microsoft Academic Search

We report a ductile beta-type titanium alloy with body-centered cubic (bcc) crystal structure having a low Poisson's ratio of 0.14. The almost identical ultralow bulk and shear moduli of ˜24GPa combined with an ultrahigh strength of ˜0.9GPa contribute to easy crystal distortion due to much-weakened chemical bonding of atoms in the crystal, leading to significant elastic softening in tension and

Y. L. Hao; S. J. Li; B. B. Sun; M. L. Sui; R. Yang



Poisson's ratio over two centuries: challenging hypotheses  

PubMed Central

This article explores Poisson's ratio, starting with the controversy concerning its magnitude and uniqueness in the context of the molecular and continuum hypotheses competing in the development of elasticity theory in the nineteenth century, moving on to its place in the development of materials science and engineering in the twentieth century, and concluding with its recent re-emergence as a universal metric for the mechanical performance of materials on any length scale. During these episodes France lost its scientific pre-eminence as paradigms switched from mathematical to observational, and accurate experiments became the prerequisite for scientific advance. The emergence of the engineering of metals followed, and subsequently the invention of composites—both somewhat separated from the discovery of quantum mechanics and crystallography, and illustrating the bifurcation of technology and science. Nowadays disciplines are reconnecting in the face of new scientific demands. During the past two centuries, though, the shape versus volume concept embedded in Poisson's ratio has remained invariant, but its application has exploded from its origins in describing the elastic response of solids and liquids, into areas such as materials with negative Poisson's ratio, brittleness, glass formation, and a re-evaluation of traditional materials. Moreover, the two contentious hypotheses have been reconciled in their complementarity within the hierarchical structure of materials and through computational modelling. PMID:24687094

Greaves, G. Neville



Omniclassical Diffusion in Low Aspect Ratio Tokamaks  

SciTech Connect

Recently reported numerical results for axisymmetric devices with low aspect ratio A found radial transport enhanced over the expected neoclassical value by a factor of 2 to 3. In this paper, we provide an explanation for this enhancement. Transport theory in toroidal devices usually assumes large A, and that the ratio B{sub p}/B{sub t} of the poloidal to the toroidal magnetic field is small. These assumptions result in transport which, in the low collision limit, is dominated by banana orbits, giving the largest collisionless excursion of a particle from an initial flux surface. However in a small aspect ratio device one may have B{sub p}/B{sub t} {approx} 1, and the gyroradius may be larger than the banana excursion. Here, we develop an approximate analytic transport theory valid for devices with arbitrary A. For low A, we find that the enhanced transport, referred to as omniclassical, is a combination of neoclassical and properly generalized classical effects, which become dominant in the low-A, B{sub p}/B{sub t} {approx} 1 regime. Good agreement of the analytic theory with numerical simulations is obtained.

H.E. Mynick; R.B. White; D.A. Gates



34 CFR 303.162 - Central directory.  

Code of Federal Regulations, 2011 CFR

...2010-07-01 true Central directory. 303.162 Section 303...EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION...Requirements § 303.162 Central directory. Each application must...State has developed a central directory of information that meets...



34 CFR 303.162 - Central directory.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Central directory. 303.162 Section 303...EDUCATION AND REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION...Requirements § 303.162 Central directory. Each application must...State has developed a central directory of information that meets...



34 CFR 303.117 - Central directory.  

Code of Federal Regulations, 2014 CFR

... 2013-07-01 true Central directory. 303.117...Statewide System § 303.117 Central directory. Each system must include a central directory that is accessible...their families; and (c) Research and demonstration...



34 CFR 303.117 - Central directory.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Central directory. 303.117...Statewide System § 303.117 Central directory. Each system must include a central directory that is accessible...their families; and (c) Research and demonstration...



34 CFR 303.117 - Central directory.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Central directory. 303.117...Statewide System § 303.117 Central directory. Each system must include a central directory that is accessible...their families; and (c) Research and demonstration...



Universidad Central de Venezuela Facultad de Ciencias  

E-print Network

Universidad Central de Venezuela Facultad de Ciencias Escuela de Computación Lecturas en Ciencias, Universidad Central de Venezuela, Ap. 47002, Caracas 1041-A, Venezuela (mmonsalv, Universidad Central de Venezuela, Ap. 47002, Caracas 1041-A, Venezuela (mraydan

Raydan, Marcos


20 CFR 346.1 - Central register.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Central register. 346.1 Section 346.1 Employees... RAILROAD HIRING § 346.1 Central register. (a) The Board shall maintain a central register of railroad employees with at...



Distribution of heating in an LVRF bundle due to dysprosium in the central element  

SciTech Connect

The computer code MCNP was used to establish the effect of adding dysprosium to the central pin of the proposed BRUCE-B CANFLEX{sup R} Low-Void-Reactivity Fuel (LVRF) on the heat load of the central pin and the heat balance inside the fuel bundle. The Dy generates heat through radiative capture of thermal neutrons, as well as through beta decay of {sup 165}Dy to {sup 165}Ho. We conclude that for fresh fuel, the presence of Dy contributes 26% of the overall heat to the central pin, and 0.5% to the whole fuel bundle. These percentages decrease to 11% and 0.5% at the end-of-life burnup condition. A second, operational quantity is the HPFP ratio (heating-power to fission-power ratio). This ratio is 1.63 for fresh fuel and decreases to 1.19 for fuel at the end-of-life burnup condition. (authors)

Tsang, K.; Buijs, A. [Atomic Energy of Canada Limited, 2251 Speakman Drive, Mississauga, Ont. L5K 1B2 (Canada)



Irreversible diesel cycle -- fine tuning of compression ratio and cut-off ratio  

SciTech Connect

A simplified irreversible model has been proposed for the air-standard Diesel cycle. Global thermal and friction losses have been lumped into an equivalent friction term. Optimization of the cycle has been performed for power output as well as for thermal efficiency with respect to compression ratio and cut-off ratio. The optimum values of these ratios compare well with standard values used in real Diesel engines. The cycle also demonstrates a loop-shaped power-versus-efficiency curve as is exhibited by real heat engines.

Bhattacharyya, S.



Central dynamics of globular clusters  

NASA Astrophysics Data System (ADS)

This dissertation explores some aspects of the central dynamics of globular clusters. Surface brightness profiles are measured with a newly developed technique that yields accurate, high resolution density profiles. The technique uses integrated light measured with a robust statistical estimator, and it is applied to images obtained by the Hubble Space Telescope . Surface brightness profiles are presented for 39 globular clusters belonging to the Milky Way, 21 to the LMC, 5 to the SMC and 4 to the Fornax dwarf galaxy. Results show that the central structure of some globular clusters departs from the predictions made by classic dynamical models. When the distribution of central logarithmic slopes is analyzed, instead of finding a bimodal distribution between flat cores and steep cusps (as expected for post core-collapse clusters), a continuous distribution of central slopes is observed. A new sub-class of objects is found that have intermediate slopes between flat cores and the expected post-core collapse central slope. In total, 45% of the sample is not consistent with having King-type profiles in the center. Omega Centauri, the largest Galactic globular cluster, is one of the objects that deviates from a flat core, having a central logarithmic slope clearly different than zero. In order to further explore the dynamical state of this cluster, central kinematic measurements are obtained. Spectroscopic measurements come from the GMOS-IFU on the Gemini-south telescope. Line-of-sight velocity dispersions from integrated spectra are measured in an area of 5=D75 arcseconds around the center and also 14 arcseconds away. A clear rise in dispersion from 18.5 to 23 km s -1 is observed between the outer and the central fields. The observed velocity dispersion profile is compared with dynamical models containing central black holes of various masses. Observations are best explained by the presence of an intermediate-mass black hole of [Special characters omitted.] at the center. It is crucial to investigate the central regions of globular clusters in great detail in order to find the causes for the observed photometric and kinematic peculiarities.

Noyola, Eva


Noise of Embedded High Aspect Ratio Nozzles  

NASA Technical Reports Server (NTRS)

A family of high aspect ratio nozzles were designed to provide a parametric database of canonical embedded propulsion concepts. Nozzle throat geometries with aspect ratios of 2:1, 4:1, and 8:1 were chosen, all with convergent nozzle areas. The transition from the typical round duct to the rectangular nozzle was designed very carefully to produce a flow at the nozzle exit that was uniform and free from swirl. Once the basic rectangular nozzles were designed, external features common to embedded propulsion systems were added: extended lower lip (a.k.a. bevel, aft deck), differing sidewalls, and chevrons. For the latter detailed Reynolds-averaged Navier-Stokes (RANS) computational fluid dynamics (CFD) simulations were made to predict the thrust performance and to optimize parameters such as bevel length, and chevron penetration and azimuthal curvature. Seventeen of these nozzles were fabricated at a scale providing a 2.13 inch diameter equivalent area throat." ! The seventeen nozzles were tested for far-field noise and a few data were presented here on the effect of aspect ratio, bevel length, and chevron count and penetration. The sound field of the 2:1 aspect ratio rectangular jet was very nearly axisymmetric, but the 4:1 and 8:1 were not, the noise on their minor axes being louder than the major axes. Adding bevel length increased the noise of these nozzles, especially on their minor axes, both toward the long and short sides of the beveled nozzle. Chevrons were only added to the 2:1 rectangular jet. Adding 4 chevrons per wide side produced some decrease at aft angles, but increased the high frequency noise at right angles to the jet flow. This trend increased with increasing chevron penetration. Doubling the number of chevrons while maintaining their penetration decreased these effects. Empirical models of the parametric effect of these nozzles were constructed and quantify the trends stated above." Because it is the objective of the Supersonics Project that future design work be done more by physics-based computations and less by experiments, several codes under development were evaluated against these test cases. Preliminary results show that the RANS-based code JeNo predicts the spectral directivity of the low aspect ratio jets well, but has no capability to predict the non-axisymmetry. An effort to address this limitations, used in the RANS-based code of Leib and Goldstein, overpredicted the impact of aspect ratio. The broadband shock noise code RISN, also limited to axisymmetric assumptions, did a good job of predicting the spectral directivity of underexpanded 2:1 cold jet case but was not as successful on high aspect ratio jets, particularly when they are hot. All results are preliminary because the underlying CFD has not been validated yet. An effort using a Large Eddy Simulation code by Stanford University predicted noise that agreed with experiments to within a few dB.

Bridges, James E.



Total Protein and Albumin/Globulin Ratio Test  


... be limited. Search Help? Total Protein and A/G Ratio Share this page: Was this page helpful? ... proteins. The ratio of albumin to globulin (A/G ratio) is calculated from measured albumin and calculated ...


Ocean's 16: Optimal protein:RNA ratio has near Redfield nitrogen:phosphorus ratio  

NASA Astrophysics Data System (ADS)

One of the biosphere’s most intriguing patterns is the near equality of the atomic nitrogen:phosphorus ratio (N:P) found in waters throughout the deep ocean (~16) and its average in plankton in the upper ocean. When Redfield discovered this pattern 75 years ago, he suggested that it is driven by the cellular composition of plankton. However, no theoretical explanation for an N:P ~16 in microorganisms has ever been found. Moreover, recently it has been suggested that N:P ~16 may have no significance for either plankton nor for N/P cycling on geological time scales. Here we show that an N:P ratio of 16 emerges from fundamental biochemical and biomolecular properties: N in amino acids, N and P in nucleotides, and the square root of the ratio of the maximal translation and transcription rates. Our theoretical results are supported by a comprehensive compilation of literature data on microbial protein:rRNA ratios. Thus, the N:P ratio of ~16 appears to correspond to the biochemically optimal protein:RNA ratio for maximal growth rates for both prokaryotes and eukaryotes.

Elser, J. J.; Loladze, I.



Cytoplasm-to-myonucleus ratios following microgravity  

NASA Technical Reports Server (NTRS)

The cytoplasmic volume-to-myonucleus ratio in the tibialis anterior and gastrocnemius muscles of juvenile rats after 5.4 days of microgravity was studied. Three groups of rats (n = 8 each) were used. The experimental group (space rats) was flown aboard the space shuttle Discovery (NASA, STS-48), while two ground-based groups, one hindlimb suspended (suspended rats), one non-suspended (control), served as controls. Single fibre analysis revealed a significant decrease in cross-sectional area (microns2) in the gastrocnemius for both the space and the suspended rats; in the tibialis anterior only the suspended rats showed a significant decrease. Myonuclei counts (myonuclei per mm) in both the tibialis anterior and gastrocnemius were significantly increased in the space rats but not in the suspended rats. The mean myonuclear volume (individual nuclei: microns3) in tibialis anterior fibres from the space rats, and in gastrocnemius fibres from both the space and the suspended rats, was significantly lower than that in the respective control group. Estimation of the total myonuclear volume (microns3, however, revealed no significant differences between the three groups in either the tibialis anterior or gastrocnemius. The described changes in the cross-sectional area and myonuclei numbers resulted in significant decreases in the cytoplasmic volume-to-myonucleus ratio (microns3 x 10(3)) in both muscles and for both space and suspended rats (tibialis anterior; 15.6 +/- 0.6 (space), 17.2 +/- 1.0 (suspended), 20.8 +/- 0.9 (control): gastrocnemius; 13.4 +/- 0.4 (space) and 14.9 +/- 1.1 (suspended) versus 18.1 +/- 1.1 (control)). These results indicate that even short periods of unweighting due to microgravity or limb suspension result in changes in skeletal muscle fibres which lead to significant decreases in the cytoplasmic volume-to-myonucleus ratio.

Kasper, C. E.; Xun, L.



Efficient computations with the likelihood ratio distribution.  


What is the probability that the likelihood ratio exceeds a threshold t, if a specified hypothesis is true? This question is asked, for instance, when performing power calculations for kinship testing, when computing true and false positive rates for familial searching and when computing the power of discrimination of a complex mixture. Answering this question is not straightforward, since there is are a huge number of possible genotypic combinations to consider. Different solutions are found in the literature. Several authors estimate the threshold exceedance probability using simulation. Corradi and Ricciardi [1] propose a discrete approximation to the likelihood ratio distribution which yields a lower and upper bound on the probability. Nothnagel et al. [2] use the normal distribution as an approximation to the likelihood ratio distribution. Dørum et al. [3] introduce an algorithm that can be used for exact computation, but this algorithm is computationally intensive, unless the threshold t is very large. We present three new approaches to the problem. Firstly, we show how importance sampling can be used to make the simulation approach significantly more efficient. Importance sampling is a statistical technique that turns out to work well in the current context. Secondly, we present a novel algorithm for computing exceedance probabilities. The algorithm is exact, fast and can handle relatively large problems. Thirdly, we introduce an approach that combines the novel algorithm with the discrete approximation of Corradi and Ricciardi. This last approach can be applied to very large problems and yields a lower and upper bound on the exceedance probability. The use of the different approaches is illustrated with examples from forensic genetics, such as kinship testing, familial searching and mixture interpretation. The algorithms are implemented in an R-package called DNAprofiles, which is freely available from CRAN. PMID:25450782

Kruijver, Maarten



Retrotrapezoid nucleus and central chemoreception.  


The 'distributed chemoreception theory' attributes the central chemoreflex (the stimulation of breathing by CNS acidification) to the cumulative effects of pH on multiple classes of respiratory neurons as well as on their tonic sources of drive. Opinions differ as to how many classes of pH-sensitive neurons contribute to the central chemoreflex but the number of candidates is high and growing fast. The 'specialized chemoreceptor theory', endorsed here, attributes the chemoreflex to a limited number of specialized neurons. These neurons (the central chemoreceptors) would drive a respiratory pattern generator that is not or minimally activated by acidification. In this review we first describe the properties of the retrotrapezoid nucleus (RTN) and argue that this nucleus may contain the most important central chemoreceptors. Next, we subject the assumptions that underlie the distributed chemoreception theory to a critical analysis. We propose several explanations for the apparent contradiction between the two competing theories of central chemoreception. We attribute much of the current controversy to premature extrapolations of the effects of acidification on neurons recorded in vitro (chemosensitivity) and to a semantic confusion between chemosensitivity and chemoreception (the mechanism by which CO(2) or pH activates breathing in vivo). PMID:18308822

Guyenet, Patrice G; Stornetta, Ruth L; Bayliss, Douglas A



Network Centrality of Metro Systems  

PubMed Central

Whilst being hailed as the remedy to the world’s ills, cities will need to adapt in the 21st century. In particular, the role of public transport is likely to increase significantly, and new methods and technics to better plan transit systems are in dire need. This paper examines one fundamental aspect of transit: network centrality. By applying the notion of betweenness centrality to 28 worldwide metro systems, the main goal of this paper is to study the emergence of global trends in the evolution of centrality with network size and examine several individual systems in more detail. Betweenness was notably found to consistently become more evenly distributed with size (i.e. no “winner takes all”) unlike other complex network properties. Two distinct regimes were also observed that are representative of their structure. Moreover, the share of betweenness was found to decrease in a power law with size (with exponent 1 for the average node), but the share of most central nodes decreases much slower than least central nodes (0.87 vs. 2.48). Finally the betweenness of individual stations in several systems were examined, which can be useful to locate stations where passengers can be redistributed to relieve pressure from overcrowded stations. Overall, this study offers significant insights that can help planners in their task to design the systems of tomorrow, and similar undertakings can easily be imagined to other urban infrastructure systems (e.g., electricity grid, water/wastewater system, etc.) to develop more sustainable cities. PMID:22792373

Derrible, Sybil



High aspect ratio, remote controlled pumping assembly  


A miniature dual syringe-type pump assembly which has a high aspect ratio and which is remotely controlled, for use such as in a small diameter penetrometer cone or well packer used in water contamination applications. The pump assembly may be used to supply and remove a reagent to a water contamination sensor, for example, and includes a motor, gearhead and motor encoder assembly for turning a drive screw for an actuator which provides pushing on one syringe and pulling on the other syringe for injecting new reagent and withdrawing used reagent from an associated sensor.

Brown, Steve B. (Livermore, CA); Milanovich, Fred P. (Lafayette, CA)



Energy Balance Bowen Ratio Station (EBBR) Handbook  

SciTech Connect

The energy balance Bowen ratio (EBBR) system produces 30-minute estimates of the vertical fluxes of sensible and latent heat at the local surface. Flux estimates are calculated from observations of net radiation, soil surface heat flux, and the vertical gradients of temperature and relative humidity (RH). Meteorological data collected by the EBBR are used to calculate bulk aerodynamic fluxes, which are used in the Bulk Aerodynamic Technique (BA) EBBR value-added product (VAP) to replace sunrise and sunset spikes in the flux data. A unique aspect of the system is the automatic exchange mechanism (AEM), which helps to reduce errors from instrument offset drift.

Cook, DR



Implications of Fast Reactor Transuranic Conversion Ratio  

SciTech Connect

Theoretically, the transuranic conversion ratio (CR), i.e. the transuranic production divided by transuranic destruction, in a fast reactor can range from near zero to about 1.9, which is the average neutron yield from Pu239 minus 1. In practice, the possible range will be somewhat less. We have studied the implications of transuranic conversion ratio of 0.0 to 1.7 using the fresh and discharge fuel compositions calculated elsewhere. The corresponding fissile breeding ratio ranges from 0.2 to 1.6. The cases below CR=1 (“burners”) do not have blankets; the cases above CR=1 (“breeders”) have breeding blankets. The burnup was allowed to float while holding the maximum fluence to the cladding constant. We graph the fuel burnup and composition change. As a function of transuranic conversion ratio, we calculate and graph the heat, gamma, and neutron emission of fresh fuel; whether the material is “attractive” for direct weapon use using published criteria; the uranium utilization and rate of consumption of natural uranium; and the long-term radiotoxicity after fuel discharge. For context, other cases and analyses are included, primarily once-through light water reactor (LWR) uranium oxide fuel at 51 MWth-day/kg-iHM burnup (UOX-51). For CR<1, the heat, gamma, and neutron emission increase as material is recycled. The uranium utilization is at or below 1%, just as it is in thermal reactors as both types of reactors require continuing fissile support. For CR>1, heat, gamma, and neutron emission decrease with recycling. The uranium utilization exceeds 1%, especially as all the transuranic elements are recycled. exceeds 1%, especially as all the transuranic elements are recycled. At the system equilibrium, heat and gamma vary by somewhat over an order of magnitude as a function of CR. Isotopes that dominate heat and gamma emission are scattered throughout the actinide chain, so the modest impact of CR is unsurprising. Neutron emitters are preferentially found among the higher actinides, so the neutron emission varies much stronger with CR, about three orders of magnitude.

Steven J. Piet; Edward A. Hoffman; Samuel E. Bays



Sex Ratios at Birth and Environmental Temperatures  

NASA Astrophysics Data System (ADS)

The relationship between average monthly air temperature and sex ratios at birth (SRB) was analyzed for children born in Germany during the period 1946-1995. Both the absolute temperature and - more markedly - the monthly temperature deviations from the overall mean were significantly positively correlated with the SRB (P<0.01) when temperatures were time-lagged against the SRB data by -10 or -11months. It is concluded that the sex of the offspring is partially determined by environmental temperatures prior to conception.

Lerchl, Alexander


High aspect ratio, remote controlled pumping assembly  


A miniature dual syringe-type pump assembly is described which has a high aspect ratio and which is remotely controlled, for use such as in a small diameter penetrometer cone or well packer used in water contamination applications. The pump assembly may be used to supply and remove a reagent to a water contamination sensor, for example, and includes a motor, gearhead and motor encoder assembly for turning a drive screw for an actuator which provides pushing on one syringe and pulling on the other syringe for injecting new reagent and withdrawing used reagent from an associated sensor. 4 figs.

Brown, S.B.; Milanovich, F.P.



Measurement of the ?-->n+? branching ratio  

NASA Astrophysics Data System (ADS)

The branching ratio for the ? weak radiative decay has been measured to be B(?-->n+?)/(?-->anything) =[1.78+/-0.24(stat)+/-0.140.16(syst)]×10-3. A low-energy kaon beam was used to produce the ? hyperons via the reaction K-+p-->?+?0 at rest. Photons from the signal channel and ?0 decay were detected with a NaI(Tl) array. The final spectrum contains 287 events after background subtraction, an order of magnitude more events than from the only previous measurement.

Noble, A. J.; Larson, K. D.; Bassalleck, B.; Fickinger, W. J.; Hall, J. R.; Hallin, A. L.; Hasinoff, M. D.; Horváth, D.; Lowe, J.; McIntyre, E. K.; Measday, D. F.; Miller, J. P.; Roberts, B. L.; Robinson, D. K.; Sakitt, M.; Salomon, M.; Waltham, C. E.; Warner, T. M.; Whitehouse, D. A.; Wolfe, D. M.



Dilatonic Probe, Force Balance and Gyromagnetic Ratio  

E-print Network

Following the Papapetrou-Dixon-Wald procedure we derive the equation of motion for a dilatonic test body(probe) with the dilaton coupling $\\alpha = {\\sqrt {p/(2+p)}}$ in four dimension. Since the dilatonic freedom sometimes comes from extra dimensions, it is best to derive the EOM by a dimensional reduction from $(p+4)-$dimensions. We discuss about the force balance up to the gravitational spin-spin interactions via the probe technique. The force balance condition yields the saturation of a Bogomol'nyi bound and the gyromagnetic ratio of the test body.

Tetsuya Shiromizu



Ductile Titanium Alloy with Low Poisson's Ratio  

NASA Astrophysics Data System (ADS)

We report a ductile ?-type titanium alloy with body-centered cubic (bcc) crystal structure having a low Poisson’s ratio of 0.14. The almost identical ultralow bulk and shear moduli of ˜24GPa combined with an ultrahigh strength of ˜0.9GPa contribute to easy crystal distortion due to much-weakened chemical bonding of atoms in the crystal, leading to significant elastic softening in tension and elastic hardening in compression. The peculiar elastic and plastic deformation behaviors of the alloy are interpreted as a result of approaching the elastic limit of the bcc crystal under applied stress.

Hao, Y. L.; Li, S. J.; Sun, B. B.; Sui, M. L.; Yang, R.



6.RP Ratio of boys to girls  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: The ratio of the number of boys to the number of girls at school is 4:5. What fraction of the students are boys? If there are 120 boys, how many studen...


Low aspect ratio wing code validation experiment  

NASA Technical Reports Server (NTRS)

An experiment was performed on a low-aspect ratio wing to define the limits of the validity of codes which are used to predict the flow over modern fighter configurations. The focus of the experiment is to provide data at or near the true operating conditions of transonic aircraft. The Reynolds numbers reached in this experiment reproduce those experienced by an aircraft with a 5-m root chord, flying at 14 to 16 km, from Mach 0.6 to 0.8. The angle-of-attack range of the experiment extends into the regime of leading-edge separation.

Olsen, Michael E.; Seegmiller, H. L.



The Central Asia Caucacus Analyst  

NSDL National Science Digital Library

This biweekly journal is the product of the Central Asia-Caucacus Institute (CACI), an independent think tank, affiliated with the Paul H. Nitze School of Advanced International Studies at The Johns Hopkins University. The journal, which CACI has been publishing for about a year, aims to "link the business, governmental, journalistic and scholarly communities," and each issue has four or five short articles, field reports (short pieces focused on communities' assessments of a particular news event), and news bites (paragraph summaries of relevant news items). The current issue contains four articles, S. Frederick Starr's "A Federated Afghanistan?" Maria Sultan's "Avoiding Escalation in Central Asia's Southern Borderland," "Turkey's New Challenges in the Caucacus and Central Asia" by Kemal Kaya, and Miriam Lanskoy's "The Cost of the Chechen War." The journal is available online, or users can download each issue in .pdf format. Note: When we visited, the material available in .pdf format was more current than that in HTML.


Hydraulic system for a ratio change transmission  


Disclosed is a drive assembly (10) for an electrically powered vehicle (12). The assembly includes a transaxle (16) having a two-speed transmission (40) and a drive axle differential (46) disposed in a unitary housing assembly (38), an oil-cooled prime mover or electric motor (14) for driving the transmission input shaft (42), an adapter assembly (24) for supporting the prime mover on the transaxle housing assembly, and a hydraulic system (172) providing pressurized oil flow for cooling and lubricating the electric motor and transaxle and for operating a clutch (84) and a brake (86) in the transmission to shift between the two-speed ratios of the transmission. The adapter assembly allows the prime mover to be supported in several positions on the transaxle housing. The brake is spring-applied and locks the transmission in its low-speed ratio should the hydraulic system fail. The hydraulic system pump is driven by an electric motor (212) independent of the prime mover and transaxle.

Kalns, Ilmars (Northville, MI)



Ultra-High Bypass Ratio Jet Noise  

NASA Technical Reports Server (NTRS)

The jet noise from a 1/15 scale model of a Pratt and Whitney Advanced Ducted Propulsor (ADP) was measured in the United Technology Research Center anechoic research tunnel (ART) under a range of operating conditions. Conditions were chosen to match engine operating conditions. Data were obtained at static conditions and at wind tunnel Mach numbers of 0.2, 0.27, and 0.35 to simulate inflight effects on jet noise. Due to a temperature dependence of the secondary nozzle area, the model nozzle secondary to primary area ratio varied from 7.12 at 100 percent thrust to 7.39 at 30 percent thrust. The bypass ratio varied from 10.2 to 11.8 respectively. Comparison of the data with predictions using the current Society of Automotive Engineers (SAE) Jet Noise Prediction Method showed that the current prediction method overpredicted the ADP jet noise by 6 decibels. The data suggest that a simple method of subtracting 6 decibels from the SAE Coaxial Jet Noise Prediction for the merged and secondary flow source components would result in good agreement between predicted and measured levels. The simulated jet noise flight effects with wind tunnel Mach numbers up to 0.35 produced jet noise inflight noise reductions up to 12 decibels. The reductions in jet noise levels were across the entire jet noise spectra, suggesting that the inflight effects affected all source noise components.

Low, John K. C.



Flexible Conversion Ratio Fast Reactor Systems Evaluation  

SciTech Connect

Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

Neil Todreas; Pavel Hejzlar



On the Scaling Ratios for Siegel Disks  

NASA Astrophysics Data System (ADS)

The boundary of the Siegel disk of a quadratic polynomial with an irrationally indifferent fixed point and the rotation number whose continued fraction expansion is preperiodic has been observed to be self-similar with a certain scaling ratio. The restriction of the dynamics of the quadratic polynomial to the boundary of the Siegel disk is known to be quasisymmetrically conjugate to the rigid rotation with the same rotation number. The geometry of this self-similarity is universal for a large class of holomorphic maps. A renormalization explanation of this universality has been proposed in the literature. In this paper we provide an estimate on the quasisymmetric constant of the conjugacy, and use it to prove bounds on the scaling ratio of the form where s is the period of the continued fraction, and depends on the rotation number in an explicit way, while C > 1, and depend only on the maximum of the integers in the continued fraction expansion of the rotation number.

Gaidashev, Denis



Parasite Stress Predicts Offspring Sex Ratio  

PubMed Central

In this study, I predict that the global variation of offspring sex ratio might be influenced in part by the level of parasite stress. From an energetic standpoint, higher gestational costs of producing a male offspring could decrease male births in a population with limited resources. This implies that, any factor that limits the parental resources could be expected to favor female offspring production. Human sex ratio at birth (SRB) is believed to be influenced by numerous socioeconomic, biological, and environmental factors. Here, I test a prediction that parasite stress, by virtue of its effects on the general health condition, may limit the parental investment ability and therefore could influence the SRB at the population level. The statistical analysis supports this prediction, and show that the level of parasite stress has a significant inverse relation with population SRB across the world. Further, this relation is many-folds stronger than the association of SRB with other factors, like; polygyny, fertility, latitude, and son-preference. Hence, I propose that condition affecting ability of parasites (but not adaptive significance) could be a likely causal basis for the striking variation of SRB across populations. PMID:23049967

Dama, Madhukar Shivajirao



Nutrient stoichiometry in Sphagnum along a nitrogen deposition gradient in highly polluted region of Central-East Europe  

Microsoft Academic Search

We investigated the variation of N:P and N:K ratio in ombrotrophic Sphagnum plants along a gradient of atmospheric N deposition from 1 to 2.5 g m?2 year?1 in Central-East Europe. The N:P and N:K ratio in Sphagnum capitula increased significantly along the N deposition gradient. Sphagnum species from the Cuspidata section were characterised by significantly lower ratios at low N deposition. When we

Martin Jiroušek; Michal Hájek; Luca Bragazza




Microsoft Academic Search

The central scheme of Nessyahu and Tadmor (J. Comput. Phys, 87(1990)) has the benefit of not having to deal with the solution within the Riemann fan for solving hyperbolic conservation laws and related equations. But the staggered averaging causes large dissipation when the time step size is small comparing to the mesh size. The recent work of Kurganov and Tadmor

Yingjie Liu


Estimating the Isotope Ratio of Ecosystem Respiration Using the Keeling Plot and the Flux Ratio Method  

NASA Astrophysics Data System (ADS)

Stable carbon isotope analyses have been used in identifying global carbon sources and sinks and in partitioning ecosystem CO2 exchange into component fluxes. The isotope ratio of ecosystem respiration (? 13Cr) is a critical parameter in applying stable isotope techniques to carbon cycle problems. The commonly used Keeling plot method in estimating ? 13Cr has limitations related to: 1) insufficient range of CO2 mixing ratio; 2) high sensitivity to curve-fitting techniques; and 3) extrapolation of CO2 mixing ratio beyond observations. In this study, the Keeling plot method was examined and compared with the flux ratio approach using continuous measurements of the mixing ratios of 12CO2 and 13CO2 over an extensive corn canopy during the 2003 growing season. The seasonal variation of ? 13Cr estimated from both methods harmonized with the ecosystem phenology. The ? 13Cr started to increase (became more positive) from mid June and peaked in early August, followed by a decrease into October. The Keeling plot method agreed well with the flux ratio method in the seasonal pattern of ? 13Cr, but tended to give lower values (more negative). The discrepancy between the two approaches was significant in July and August (about 5 per mil) and relatively small in June and September (about 1 to 2 per mil). We examined this discrepancy with respect to wind direction/advection and measurement footprints. In addition, our analysis of high-frequency data (every two minutes) using the flux ratio method indicates that ? 13Cr may vary significantly at short time-scales (e.g., hourly), which could have significant implications for flux partitioning studies.

Zhang, J.; Griffis, T. J.; Baker, J. M.



Prediction of Central Burst Defects in Copper Wire Drawing Process  

NASA Astrophysics Data System (ADS)

In this study, the prediction of chevron cracks (central bursts) in copper wire drawing process is investigated using experimental and numerical approaches. The conditions of the chevron cracks creation along the wire axis depend on (i) the die angle, the friction coefficient between the die and the wire, (ii) the reduction in crosssectional area of the wire, (iii) the material properties and (iv) the drawing velocity or strain rate. Under various drawing conditions, a numerical simulation for the prediction of central burst defects is presented using an axisymmetric finite element model. This model is based on the application of the Cockcroft and Latham fracture criterion. This criterion was used as the damage value to estimate if and where defects will occur during the copper wire drawing. The critical damage value of the material is obtained from a uniaxial tensile test. The results show that the die angle and the reduction ratio have a significant effect on the stress distribution and the maximum damage value. The central bursts are expected to occur when the die angle and reduction ratio reach a critical value. Numerical predictions are compared with experimental observations.

Vega, G.; Haddi, A.; Imad, A.



Prediction of Central Burst Defects in Copper Wire Drawing Process  

SciTech Connect

In this study, the prediction of chevron cracks (central bursts) in copper wire drawing process is investigated using experimental and numerical approaches. The conditions of the chevron cracks creation along the wire axis depend on (i) the die angle, the friction coefficient between the die and the wire, (ii) the reduction in crosssectional area of the wire, (iii) the material properties and (iv) the drawing velocity or strain rate. Under various drawing conditions, a numerical simulation for the prediction of central burst defects is presented using an axisymmetric finite element model. This model is based on the application of the Cockcroft and Latham fracture criterion. This criterion was used as the damage value to estimate if and where defects will occur during the copper wire drawing. The critical damage value of the material is obtained from a uniaxial tensile test. The results show that the die angle and the reduction ratio have a significant effect on the stress distribution and the maximum damage value. The central bursts are expected to occur when the die angle and reduction ratio reach a critical value. Numerical predictions are compared with experimental observations.

Vega, G. [Laboratoire de Mecanique de Lille, CNRS UMR 8107, Universite de Lille 1, Cite Scientifique, Avenue Paul Langevin, F-59655 Villeneuve d'Ascq (France); NEXANS France, NMC Nexans Metallurgy Centre, Boulevard du Marais, BP39, F-62301 Lens (France); Haddi, A. [Laboratoire Genie Civil et geo-Environnement (LGCgE), Faculte des Sciences Appliquees, Universite d'Artois, F-62400 Bethune (France); Imad, A. [Laboratoire de Mecanique de Lille, CNRS UMR 8107, Universite de Lille 1, Cite Scientifique, Avenue Paul Langevin, F-59655 Villeneuve d'Ascq (France)



Geothermal activities in Central America  

SciTech Connect

The Agency for International Development is funding a new program in energy and minerals for Central America. Geothermal energy is an important component. A country-wide geothermal assessment has started in Honduras, and other assessment activities are in progress or planned for Costa Rica, El Salvador, Guatemala, and Panama. Instrumentation for well logging has been provided to Costa Rica, and a self-contained logging truck will be made available for use throughout Central America. An important objective of this program is to involve the private sector in resource development. 4 refs., 3 figs.

Whetten, J.T.; Hanold, R.J.



Clinical manifestations of central neurocytoma.  


Central neurocytomas (CNs) are rare central nervous system tumors that occur in the lateral ventricles. They are prevalent in young adults and are typically benign with excellent prognosis following surgical resection. Because of the rarity of the disease and its similar features with more common tumors, misdiagnosis becomes an issue. Optimal treatment is achieved only when the correct tumor types are distinguished. Typical clinical manifestations include symptoms of increased intracranial pressure, although no clinical feature is pathognomonic to CN. Radiologic imaging, histology, magnetic resonance spectroscopy, and immunohistochemistry must be used to elucidate tumor characteristics and properly diagnose CN. PMID:25432178

Yang, Isaac; Ung, Nolan; Chung, Lawrance K; Nagasawa, Daniel T; Thill, Kimberly; Park, Junmook; Tenn, Stephen



Predicting Lumbar Central Canal Stenosis – A Magnetic Resonance Imaging Study  

PubMed Central

Background: Low back pain is a common complaint among adults, worldwide. Lumbar canal stenosis is frequently diagnosed as a cause for low back pain. In this study we evaluate morphometric measures using MRI sections to predict the occurrence of lumbar central canal stenosis. Settings and Design: One hundred and fifty four lumbar spinal MRI sagital and axial section images, 77 males and females each were evaluated from the Department of Radiology, Kasturba Medical College, Mangalore, Manipal University. The study design was a prospective study. Materials and Methods: Various measurements were taken and two constant ratios were calculated. The Canal Body Ratio and the Ratio between the area of the dural sac and the vertebral body was evaluated. Statistical analysis: Unpaired t-test analysis was conducted using SPSS software. Results: A canal body ratio less than 0.6 from L1 to L3 levels and less than 0.5 at L4 and L5 levels were found. The ratio between area of dural sac and vertebral body was found to be a constant at 0.2 at all levels. It was found that maximum central canal stenosis occurred at the L5 lumbar vertebral level in 15.6% males and 13% females. This was followed by stenosis at the L4 and L3 lumbar vertebral levels with 5.1% males having stenosis at both levels and 3.9% and 5.1% females in L4 and L3 lumbar levels respectively. Conclusion: These morphometrical findings of the lumbar vertebrae could be of use in evaluating the possible cases of lumbar canal stenosis.

Premchandran, Divya; Mahale, Ajith



HII and H2 in the envelopes of cooling flow central galaxies  

E-print Network

We report observations of ionized and warm molecular gas in the extended regions of the central galaxies in several cooling flow clusters. These show that both gas phases are present in these clusters to large radii. We trace both Pa alpha and H2 lines to radii in excess of 20 kpc. The surface brightness profiles of the two phases trace each other closely. Apart from very close to the central AGN, line ratios in and between the phases vary only slowly with position. The kinematics of the phases are indistinguishable and away from the influence of the central AGN both the mean and dispersion in velocity are low (= 10^5 K.

W. Jaffe; M. N. Bremer; K. Baker



On Monte Carlo methods for estimating ratios of normalizing constants  

Microsoft Academic Search

Recently, estimating ratios of normalizing constants has played an important role in Bayesian computations. Applications of estimating ratios of normalizing constants arise in many aspects of Bayesian statistical inference. In this article, we present an overview and discuss the current Monte Carlo methods for estimating ratios of normalizing constants. Then we propose a new ratio importance sampling method and establish

Ming-Hui Chen; Qi-Man Shao



Isotope Ratios of Cellulose from Plants Having Different Photosynthetic Pathways  

PubMed Central

Hydrogen and carbon isotope ratios of cellulose nitrate and oxygen isotope ratios of cellulose from C3, C4, and Crassulacean acid metabolism (CAM) plants were determined for plants growing within a small area in Val Verde County, Texas. Plants having CAM had distinctly higher deuterium/hydrogen (D/H) ratios than plants having C3 and C4 metabolism. When hydrogen isotope ratios are plotted against carbon isotope ratios, each photosynthetic mode separates into a distinct cluster of points. C4 plants had many D/H ratios similar to those of C3 plants, so that hydrogen isotope ratios cannot be used to distinguish between these two photosynthetic modes. Portulaca mundula, which may have a modified photosynthetic mode between C4 and CAM, had a hydrogen isotope ratio between those of the C4 and CAM plants. When oxygen isotope ratios are plotted against carbon isotope ratios, no distinct clustering of the C4 and CAM plants occurs. Thus, oxygen isotope ratios are not useful in distinguishing between these metabolic modes. A plot of hydrogen isotope ratios versus oxygen isotope ratios for this sample set shows considerable overlap between oxygen isotope ratios of the different photosynthetic modes without a concomitant overlap in the hydrogen isotope ratios of CAM and the other two photosynthetic modes. This observation is consistent with the hypothesis that higher D/H ratios in CAM plants relative to C3 and C4 plants are due to isotopic fractionations occurring during biochemical reactions. PMID:16663460

Sternberg, Leonel O.; Deniro, Michael J.; Johnson, Hyrum B.



The Next Generation Isotope Ratio MS DELTA V Advantage  

E-print Network

Plus The Next Generation Isotope Ratio MS The DELTA V isotope ratio mass spectrometers isotope ratio MS applications in the mass range up to m/z 96. Its versatility puts virtuallyThe Next Generation Isotope Ratio MS DELTA V Advantage DELTA V Plus Analyze · Detect · Measure

Lachniet, Matthew S.


EUV branching ratios for ionized nitrogen and oxygen emissions  

NASA Technical Reports Server (NTRS)

Branching ratios of single ionized atomic nitrogen and oxygen EUV emissions that terminate on the metastable states of the respective ions are presented. The four NII ratios and the 482/515 A ratio in OII reported represent the first measured values. Details of the wavelength calibration procedures adopted and a brief discussion of two modeling implications of the measured ratios are included.

Morrison, M. D.; Cunningham, A. J.; Christensen, A. B.



Evaluation of the normal-to-diseased apparent diffusion coefficient ratio as an indicator of prostate cancer aggressiveness  

PubMed Central

Background We tested the feasibility of a simple method for assessment of prostate cancer (PCa) aggressiveness using diffusion-weighted magnetic resonance imaging (MRI) to calculate apparent diffusion coefficient (ADC) ratios between prostate cancer and healthy prostatic tissue. Methods The requirement for institutional review board approval was waived. A set of 20 standardized core transperineal saturation biopsy specimens served as the reference standard for placement of regions of interest on ADC maps in tumorous and normal prostatic tissue of 22 men with PCa (median Gleason score: 7; range, 6–9). A total of 128 positive sectors were included for evaluation. Two diagnostic ratios were computed between tumor ADCs and normal sector ADCs: the ADC peripheral ratio (the ratio between tumor ADC and normal peripheral zone tissue, ADC-PR), and the ADC central ratio (the ratio between tumor ADC and normal central zone tissue, ADC-CR). The performance of the two ratios in detecting high-risk tumor foci (Gleason 8 and 9) was assessed using the area under the receiver operating characteristic curve (AUC). Results Both ADC ratios presented significantly lower values in high-risk tumors (0.48?±?0.13 for ADC-CR and 0.40?±?0.09 for ADC-PR) compared with low-risk tumors (0.66?±?0.17 for ADC-CR and 0.54?±?0.09 for ADC-PR) (p?ratio as an intrapatient-normalized diagnostic tool may be better in detecting high-grade lesions compared with analysis based on tumor ADCs alone, and may reduce the rate of biopsies. PMID:24885552



Effects of a Signaled Delay to Reinforcement in the Previous and Upcoming Ratios on Between-Ratio Pausing in Fixed-Ratio Schedules  

ERIC Educational Resources Information Center

Domestic hens responded under multiple fixed-ratio fixed-ratio schedules with equal fixed ratios. One component provided immediate reinforcement and the other provided reinforcement after a delay, signaled by the offset of the key light. The components were presented quasi-randomly so that all four possible transitions occurred in each session.…

Harris, Aimee; Foster, T. Mary; Levine, Joshua; Temple, William



Renalase regulates peripheral and central dopaminergic activities.  


Renalase is a recently identified FAD/NADH-dependent amine oxidase mainly expressed in kidney that is secreted into blood and urine where it was suggested to metabolize catecholamines. The present study evaluated central and peripheral dopaminergic activities in the renalase knockout (KO) mouse model and examined the changes induced by recombinant renalase (RR) administration on plasma and urine catecholamine levels. Compared with wild-type (WT) mice, KO mice presented increased plasma levels of epinephrine (Epi), norepinephrine (NE), and dopamine (DA) that were accompanied by increases in the urinary excretion of Epi, NE, DA. In addition, the KO mice presented an increase in urinary DA-to-l-3,4-dihydroxyphenylalanine (l-DOPA) ratios without changes in renal tubular aromatic-l-amino acid decarboxylase (AADC) activity. By contrast, the in vivo administration of RR (1.5 mg/kg sc) to KO mice was accompanied by significant decreases in plasma levels of Epi, DA, and l-DOPA as well as in urinary excretion of Epi, DA, and DA-to-l-DOPA ratios notwithstanding the accompanied increase in renal AADC activity. In addition, the increase in renal DA output observed in renalase KO mice was accompanied by an increase in the expression of the L-type amino acid transporter like (LAT) 1 that is reversed by the administration of RR in these animals. These results suggest that the overexpression of LAT1 in the renal cortex of the renalase KO mice might contribute to the enhanced l-DOPA availability/uptake and consequently to the activation of the renal dopaminergic system in the presence of renalase deficiency. PMID:25411385

Quelhas-Santos, Janete; Serrão, Maria Paula; Soares-Silva, Isabel; Fernandes-Cerqueira, Cátia; Simões-Silva, Liliana; Pinho, Maria João; Remião, Fernando; Sampaio-Maia, Benedita; Desir, Gary V; Pestana, Manuel



Isotopic ratio measurements with ICP-MS  

SciTech Connect

An inductively-coupled-plasma source mass spectrometer (ICP-MS) has been used to measure the isotopic composition of U, Pb, Os, and B standards. Particular emphasis has been placed on uranium because of its nuclear and environmental interest and because of the availability of a well-characterized set of standards with a wide range of isotopic compositions. The precision and accuracy obtainable in isotope ratio measurements by ICP-MS depend on many factors including background, interferences, dead time, mass fractionation (bias), abundance sensitivity, and counting statistics. Which, if any, of these factors controls accuracy and precision depends on the type of sample being analyzed and the characteristics of the mass spectrometer. These issues are discussed in detail.

Russ, G.P. III; Bazan, J.M.



High resolution color band pyrometer ratioing  

NASA Technical Reports Server (NTRS)

The sensing head of a two-color band ratioing pyrometer of a known type using a fiber optic cable to couple radiation to dual detector photodiodes is improved to have high spatial resolution by focusing the radiation received through an objective lens (i.e., by focusing the image of a target area) onto an opaque sheet spaced in front of the input end of the fiber optic cable. A two-mil hole in that sheet then passes radiation to the input end of the cable. The detector has two channels, one for each color band, with an electronic-chopper stabilized current amplifier as the input stage followed by an electronic-chopper stabilized voltage amplifier.

Bickler, Donald B. (Inventor); Henry, Paul K. (Inventor); LoGiurato, D. Daniel (Inventor)



Abundance ratios in hierarchical galaxy formation  

E-print Network

The chemical enrichment and stellar abundance ratios of galaxies which form in a hierarchical clustering scheme are calculated. For this purpose I adopt the star formation histories (SFH) as they are delivered by semi-analytic models in Kauffmann (1996}. It turns out that the average SFH of cluster ellipticals does not yield globally alpha-enhanced stellar populations. The star burst that occurs when the elliptical forms in the major merger plays therefore a crucial role in producing alpha-enhancement. Only under the assumption that the IMF is significantly flattened with respect to the Salpeter value during the burst, a Mg/Fe overabundant population can be obtained. In particular for the interpretation of radial gradients in metallicity and alpha-enhancement, the mixing of global and burst populations are of great importance. The model predicts bright field galaxies to be less alpha-enhanced than their counterparts in clusters.

D. Thomas



Readability of Central Florida Newspapers.  

ERIC Educational Resources Information Center

A study analyzed the readability of seven central Florida newspapers (one of which is a college newspaper) and "USA Today.""Rightwriter," a grammar checker and readability computer program, was used to evaluate front page articles for each of the eight newspapers. The readability formulas invoked in the readability program included the…

Olmstead, Phyllis M.


Measures of Central Tendency Rap  

NSDL National Science Digital Library

This video on basic statistics provides a short rap to help students remember the meaning of range, and the measures of central tendency, namely, mean, median, and mode. Each word is given in a short rhyme that includes how to calculate the value.

Devoto, Paul



Central configurations for -body problems  

NASA Astrophysics Data System (ADS)

We show the existence of planar central configurations for -body problems with Newtonian potentials; in such configurations, -bodies are located at the vertices of regular -gons with a common center, where regular -gons are homothetic, and regular -gons are homothetic rotated by compared to the first set of -gons, and all masses on the same -gon are equal.

Zhao, Furong; Chen, Jian



Central Corneal Thickness in Children  

PubMed Central

Objective To report the central corneal thickness (CCT) in healthy white, African-American, and Hispanic children from birth to 17 years of age. Design Prospective observational multicenter study. Central corneal thickness was measured with a hand-held contact pachymeter. Results Two thousand seventy-nine children were included in the study, with ages ranging from day of birth to 17 years. Included were 807 white, 494 Hispanic, and 474 African-American individuals, in addition to Asian, unknown and mixed race individuals. African-American children had thinner corneas on average than that of both white (p< .001) and Hispanic children (p< .001) by approximately 20 micrometers. Thicker median CCT was observed with each successive year of age from age 1 to 11 years, with year-to-year differences steadily decreasing and reaching a plateau after age 11 at 573 micrometers in white and Hispanic children and 551 micrometers in African-American children. For every 100 micrometers of thicker CCT measured, the intraocular pressure was 1.5 mmHg higher on average (p< 0.001). For every diopter of increased myopic refractive error (p< 0.001) CCT was 1 micrometer thinner on average. Conclusions Median CCT increases with age from 1 to 11 years with the greatest increase present in the youngest age groups. African-American children on average have thinner central corneas than white and Hispanic children, while white and Hispanic children demonstrate similar central corneal thickness. PMID:21911662



Arnold Schwarzenegger THE CENTRAL CALIFORNIA  

E-print Network

. It was coordinated with the California Regional PM2.5/PM10 Air Quality Study (CRPAQS) which sought to improve a coordinated air quality/meteorology field program extending from 1 December 1999 through 31 January 2001Arnold Schwarzenegger Governor THE CENTRAL CALIFORNIA OZONE STUDY APPENDIX D: METEOROLOGICAL


Investing in the Central Office  

ERIC Educational Resources Information Center

Benchmarking against similar districts, ideally higher-performing ones, can be a valuable tool for determining the appropriate level of central-office investment. Unfortunately, reliable benchmarks on district spending in teaching and learning support are not readily available. This should not preclude districts from using this valuable method to…

Shields, Regis Anne



Wooden Calendars from Central Rhodopes  

Microsoft Academic Search

Four wooden calendars from the village of Polkovnik Serafimovo, Smolyan region, in the Central Rhodopes are presented here, and three of them - for the first time. The shape and size, the kind of the signs and structure of the calendar record bear the characteristic features of the rest of the Bulgarian wooden calendars. The short notches on the edges




Georgiaites: Tektites in Central Georgia.  

ERIC Educational Resources Information Center

Information is provided about the origin, the features, and the availability of tektites which are odd and very rare types of transparent glass theorized to be from a common, yet unknown, origin. The basis for this article is the Howard collection of tektites found in a small region of central Georgia. (seven references) (JJK)

Albin, Edward F.



High-gravity central stars  

E-print Network

NLTE spectral analyses of high-gravity central stars by means of state-of-the-art model atmosphere techniques provide information about the precursor AGB stars. The hydrogen-deficient post-AGB stars allow investigations on the intershell matter which is apparently exhibited at the stellar surface. We summarize recent results from imaging, spectroscopy, and spectropolarimetry.

Thomas Rauch



India's interests in Central Asia  

Microsoft Academic Search

Central Asia is a new geopolitical creation which has an important strategic role to play in the coming years. It is in the middle of three super civilisations—the Islamic, the Christian and the Buddhist and is seen by many experts as one of the most vulnerable areas of instability between them. It can become a natural, historically formed buffer zone

Meena Singh Roy



Central New York's New Workforce  

ERIC Educational Resources Information Center

Conducted in late 2008 in partnership with the Greater Syracuse Chamber of Commerce and the Mohawk Valley Chamber of Commerce, this is the largest survey ever taken of Central New York businesses regarding the English language skills of the area workforce. The online survey was emailed to several hundred local businesses; 126 responses were…

Center for an Urban Future, 2009



Central American geologic map project  

SciTech Connect

During the Northeast Quadrant Panel meeting of the Circum-Pacific Map Project held in Mexico City, February 1985, Central American panel members proposed and adopted plans for compiling a geologic map of Central America, probably at a scale of 1:500,000. A local group with participants from each country was organized and coordinated by Rolando Castillo, director, Central American School of Geology, University of Costa Rica, for the geologic aspects, and Fernando Rudin, director, Geographic Institute of Costa Rica, for the topographic base. In 1956, the US Geological Survey published a geologic map of the region at a scale of 1:1 million. Subsequent topographic and geologic mapping projects have provided a large amount of new data. The entire area is now covered by topographic maps at a scale of 1:50,000, and these maps have been used in several countries as a base for geologic mapping. Another regional map, the Metallogenic Map of Central America (scale = 1:2 million), was published in 1969 by the Central American Research Institute for Industry (ICAITI) with a generalized but updated geologic base map. Between 1969 and 1980, maps for each country were published by local institutions: Guatemala-Belize at 1:500,000, Honduras at 1:500,000, El Salvador at 1:100,000, Nicaragua at 1:1 million, Costa Rica at 1:200,000, and Panama at 1:1 million. This information, in addition to that of newly mapped areas, served as the base for the Central American part of the Geologic-Tectonic Map of the Caribbean Region (scale = 1:2.5 million), published by the US Geological Survey in 1980, and also fro the Northeast Quadrant Maps of the Circum-Pacific Region. The new project also involves bathymetric and geologic mapping of the Pacific and Caribbean margins of the Central American Isthmus. A substantial amount of new information of the Middle America Trench has been acquired through DSDP Legs 67 and 84.

Dengo, G.



Root-Crown Ratio in Permanent Dentition Using Panoramic Radiography in a Selected Iranian Population  

PubMed Central

Statement of the Problem: Determining the crown-root ratio is crucial in many dental clinical decisions. There are no reliable data presented for Iranian population. Purpose: The aim of this study was to assess the root-crown ratio of permanent teeth with regards to the relationship of gender and jaw type using panoramic radiographs. The reliability of method was also assessed. Materials and Method: The crown and root lengths of teeth were measured by a digital caliper on panoramic radiographs of 185 individuals except for the third molars. A total of 1994 teeth was studied and 50.8% of the teeth belonged to males and 49.2% belonged to females. The modified Lind method was applied. Results: The highest mean root-crown ratios in both arches of both genders were obtained in the second premolars, followed by the first premolars and canines. In both genders, the lowest root-crown ratios were found in the maxillary central incisors. In male patients, the mean root-crown ratio was higher (p= 0.003) than that of females. Using Bland-Altman analysis, a non-significant difference of 0.006 (95% CI: -0.012-0.024) and 0.0002 (95% CI: -0.011-0.011) were found for intra-observer and inter-observer agreement, respectively. Conclusion: Assessment of the root-crown ratio in permanent dentition could be performed on panoramic radiographs with acceptable reproducibility in an Iranian Population. Considering observed differences, our findings suggest that for the accurate assessment, this ratio must be calculated for male and female patients and also for the upper and lower jaws, separately. PMID:25469356

Haghanifar, Sina; Moudi, Ehsan; Abbasi, Shirin; Bijani, Ali; Poorsattar Bejeh Mir, Arash; Ghasemi, Nafiseh



Evolution of the differential transverse momentum correlation function with centrality in Au + Au collisions at s=200 GeV  

NASA Astrophysics Data System (ADS)

We present first measurements of the evolution of the differential transverse momentum correlation function, C, with collision centrality in Au + Au interactions at s=200 GeV. This observable exhibits a strong dependence on collision centrality that is qualitatively similar to that of number correlations previously reported. We use the observed longitudinal broadening of the near-side peak of C with increasing centrality to estimate the ratio of the shear viscosity to entropy density, ?/s, of the matter formed in central Au + Au interactions. We obtain an upper limit estimate of ?/s that suggests that the produced medium has a small viscosity per unit entropy.

STAR Collaboration; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Averichev, G. S.; Balewski, J.; Beavis, D. R.; Behera, N. K.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Biritz, B.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bridgeman, A.; Brovko, S. G.; Bruna, E.; Bueltmann, S.; Bunzarov, I.; Burton, T. P.; Cai, X. Z.; Caines, H.; Calderón de La Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, K. E.; Christie, W.; Chung, P.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Davila Leyva, A.; de Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Derevschikov, A. A.; Derradi de Souza, R.; Didenko, L.; Djawotho, P.; Dogra, S. M.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Estienne, M.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Gagliardi, C. A.; Gangadharan, D. R.; Geurts, F.; Ghosh, P.; Gorbunov, Y. N.; Gordon, A.; Grebenyuk, O. G.; Grosnick, D.; Guertin, S. M.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L.-X.; Harris, J. W.; Hays-Wehle, J. P.; Heinz, M.; Heppelmann, S.; Hirsch, A.; Hjort, E.; Hoffmann, G. W.; Hofman, D. J.; Huang, B.; Huang, H. Z.; Humanic, T. J.; Huo, L.; Igo, G.; Jacobs, P.; Jacobs, W. W.; Jena, C.; Jin, F.; Joseph, J.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kettler, D.; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Kizka, V.; Knospe, A. G.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Koroleva, L.; Korsch, W.; Kotchenda, L.; Kouchpil, V.; Kravtsov, P.; Krueger, K.; Krus, M.; Kumar, L.; Kurnadi, P.; Lamont, M. A. C.; Landgraf, J. M.; Lapointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; Levine, M. J.; Li, C.; Li, L.; Li, N.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, F.; Liu, H.; Liu, J.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Love, W. A.; Lu, Y.; Lukashov, E. V.; Luo, X.; Ma, G. L.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; Mall, O. I.; Manweiler, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; Matulenko, Yu. A.; McDonald, D.; McShane, T. S.; Meschanin, A.; Milner, R.; Minaev, N. G.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Mondal, M. M.; Morozov, B.; Morozov, D. A.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nayak, T. K.; Netrakanti, P. K.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Pachr, M.; Page, B. S.; Pal, S. K.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pei, H.; Peitzmann, T.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Ploskon, M. A.; Pluta, J.; Plyku, D.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Potukuchi, B. V. K. S.; Powell, C. B.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Raniwala, R.; Raniwala, S.; Redwine, R.; Reed, R.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmitz, N.; Schuster, T. R.; Seele, J.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Simon, F.; Singaraju, R. N.; Skoby, M. J.; Smirnov, N.; Solanki, D.; Sorensen, P.; Souza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Staszak, D.; Steadman, S. G.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Subba, N. L.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szanto de Toledo, A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; van Buren, G.; van Nieuwenhuizen, G.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Wada, M.; Walker, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Q.; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten, C.; Wieman, H.; Wissink, S. W.; Witt, R.; Witzke, W.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xu, H.; Xu, N.



Single and Central Diffractive Higgs Production at the LHC  

SciTech Connect

The single and central diffractive production of the Standard Model Higgs boson is computed using the diffractive factorization formalism, taking into account a parametrization for the Pomeron structure function provided by the H1 Collaboration. We compute the cross sections at NLO accuracy for the gluon fusion process, since it is the leading mechanism for the Higgs boson production. The gap survival probability is also introduced to include the rescattering corrections due to spectator particles present in the interaction. The diffractive ratios are predicted for proton-proton collisions at the LHC, since the beam luminosity is favorable to the Higgs boson detection. These results provide updated estimations for the fraction of single and central diffractive events in the LHC kinematical regime.

Ducati, M. B. Gay; Machado, M. M.; Silveira, G. G. [High Energy Physics Phenomenology Group, GFPAE, IF-UFRGS, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS (Brazil)



Standardizing central line safety: lessons learned for physician leaders.  


A comprehensive central venous catheter (CVC) safety program reduces mechanical and infectious complications and requires an integrated multidisciplinary effort. A multistate health care system implemented a discovery and diffusion project addressing CVC insertion, maintenance, and removal. Process and outcome measures were collected before and after the intervention. The project was completed in 12 months. It was associated with statistically significant improvement in 6 process measures and reduction in the rate of ICU central line-associated bloodstream infection (from 1.16 to 0.80 infections/1000 catheter days; incidence rate ratio = 0.69; 95% confidence interval = 0.51, 0.93). A comprehensive CVC standardization project increased compliance with several established best practices, was associated with improved outcomes, produced a refined definition of discovery and diffusion project components, and identified several discrete leadership principles that can be applied to future clinical improvement initiatives. PMID:23880777

Mueller, Jeff T; Wright, Alan J; Fedraw, Leslie A; Murad, M Hassan; Brown, Daniel R; Thompson, Kristine M; Flick, Randall; Seville, Maria Teresa A; Huskins, W Charles



N/P re-mineralization ratios across forests worldwide  

NASA Astrophysics Data System (ADS)

Decomposition of leaf litter is the primary mechanism by which nutrients are recycled in forests. Forests are a sink for atmospheric CO2, but nitrogen (N) and phosphorus (P) could limit or eliminate this ecosystem service in the future. Nutrient cycling during mineralization supplies the vast majority of nutrients to enable forest growth. Therefore, elucidating patterns by which organic N and P are mineralized by decomposing organisms or immobilized in microbial biomass is crucial to establishing controls on plant nutrient availability. Here, we compare re-mineralization N/P ratios to the stoichiometry of the initial material. We performed a meta-analysis of N and P mineralization from leaves and needles in forest ecosystems and included 112 studies, 511 litterbag sequences, and 3225 observations. Of the compiled data, net mineralization occurred in 54 studies, 372 litterbag sequences, and 1308 observations. We compare re-mineralization ratios across temperate and tropical forest systems to elucidate patterns across latitudes. We report strong and systematic regularities between decomposing litter N/P and the N/P of re-mineralization across global forests. Overall, the N/P of mineralization scales at a slope close to unity (slope = 1.4, R2=0.53, n=372), with a tendency toward higher N/P in tropical vs. temperate forests. The N/P of tropical forest re-mineralization is equal to 30/1 (R2=0.55; n=691), corresponding with the high N/P of plant foliage and litter within this biome. In contrast, the N/P of mineralization is equal to 5/1 in temperate forests (R2=0.34; n=617). A modal anomaly analysis further reveals the central tendency of mineralization N/P on that of litter, with departures from the average case tending toward a lower N/P of mineralization compared to litter substrates. These deviations suggest the potential for preferential N retention or enhanced P mineralization, or both, as opposed to more rapid N releases from decomposing organic matter. The results show that forest mineralization N/P is closely linked to the N/P of litter in a way that seems to mimic that of the global ocean environment. N/P of mineralization vs. N/P of litter. Grey symbols indicate data from each litterbag; colored symbols indicate the mean value for each litterbag sequence. Blue triangles indicate tropical forests; green plus signs indicate temperate forests. The dashed line is 1:1; the solid line is the linear regression.

Marklein, A. R.; Houlton, B. Z.



Impact parameter profiles from nuclear shadowing ratio and applications to deuteron-gold collisions  

E-print Network

While current nuclear parton distribution functions (nPDFs) from global fits to experimental data are spatially homogeneous, many experimental observables in nucleus-nucleus collisions are presented in terms of centrality cuts. These cuts can be related to impact parameter using the Glauber theory and it is thus usual in the description of such observables to convolute an assumed impact parameter distribution with the homogeneous nPDFs. In this study we use the Gribov theory of nuclear shadowing supplemented with information from diffraction to model the impact parameter distributions of nuclear shadowing ratio in the small-$x$ region. The modeled distributions are applied to the description of the centrality dependence of observables in deuteron-gold (d+Au) collisions at $\\sqrt{s_{NN}} = 200$ AGeV.

Adeola Adeluyi; Trang Nguyen; Bao-An Li



Lambda-to-kaon ratio enhancement in heavy ion collisions at several TeV.  


We introduced recently a new theoretical scheme which accounts for hydrodynamically expanding bulk matter, jets, and the interaction between the two. Important for the particle production at intermediate values of transverse momentum (p(t)) are jet hadrons produced inside the fluid. They pick up quarks and antiquarks (or diquarks) from the thermal matter rather than creating them via the Schwinger mechanism-the usual mechanism of hadron production from string fragmentation. These hadrons carry plasma properties (flavor, flow) but also the large momentum of the transversely moving string segment connecting quark and antiquark (or diquark). They therefore show up at quite large values of p(t), not polluted by soft particle production. We will show that this mechanism leads to a pronounced peak in the Lambda-to-kaon ratio at intermediate p(t). The effect increases substantially with centrality, which reflects the increasing transverse size with centrality. PMID:23005282

Werner, K




EPA Science Inventory

The hypothesis that the ratio of the adult (A) and developmental (D) toxicity of a chemical is constant across animal species has been proposed as the basis for identifying developmental hazards, both from traditional developmental toxicity screens using laboratory mammals and fr...


Subcontinental lithospheric mantle beneath Central Europe  

NASA Astrophysics Data System (ADS)

Mantle xenoliths in Oligocene-Miocene alkaline lavas in Lower Silesia (SW Poland) and adjacent part of Upper Lusatia (SE Germany) are samples of the subcontinental lithospheric mantle at the time of culmination of rifting in the Eger Rift (Bohemian Massif, Central Europe). The xenoliths come from the spinel mantle facies and show that two major lithologies occur in the area: A—highly magnesian (olivine Fo 90.5-92.0) harzburgites, and B—less magnesian (olivine Fo 84.0-90.0) harzburgites. The protolith of group A was clinopyroxene-free harzburgite being the residue after extensive melting. It was affected by chromatographic carbonatite/silicate melt metasomatism, with the carbonatite metasomatism only recorded in distal parts of the chromatographic systems. The B harzburgites were penetratively metasomatised by percolating alkaline silicate melts at the time of volcanism. That metasomatism was mostly anhydrous and typically cryptic; it lowered the Mg/(Mg + Fe) ratio of olivine and orthopyroxene in the peridotites subjected to melt percolation and led in places to dissolution of clinopyroxene. The mostly harzburgitic subcontinental mantle lithospheric domain beneath Lower Silesia and Upper Lusatia differs from the lherzolitic/harzburgitic ones located to W and SW beneath other parts of European Variscan orogen.

Puziewicz, Jacek; Matusiak-Ma?ek, Magdalena; Ntaflos, Theodoros; Grégoire, Michel; Kuku?a, Anna



Cereal Production Ratio and NDVI in Spain  

NASA Astrophysics Data System (ADS)

Droughts are long-term phenomena affecting large regions causing significant damages both in human lives and economic losses. The use of remote sensing has proved to be very important in monitoring the growth of agricultural crops and trying to asses weather impact on crop loss. Several indices has been developed based in remote sensing data being one of them the normalized difference vegetation index (NDVI). In this study we have focus to know the correlation between NDVI data and the looses of rain fed cereal in the Spanish area where this crop is majority. For this propose data from drought damage in cereal come from the pool of agricultural insurance in Spain (AGROSEGURO) including 2007/2008 to 2011/2012 (five agricultural campaigns). This data is given as a ratio between drought party claims against the insured value of production aggregated at the agrarian region level. Medium resolution (500x500 m2) MODIS images were used during the same campaigns to estimate the eight-day composites NDVI at these locations. The NDVI values are accumulated following the normal cycle of the cereal taking in account the sowing date at different sites. At the same time, CORINE Land Cover (2006) was used to classify the pixels belonging to rain fed cereal use including a set of conditions such as pixels showing dry during summer, area in which there has been no change of use. Fallow presence is studied with particular attention as it imposes an inter annual variation between crop and bare soil and causes decreases in greenness in a pixel and mix both situations. This is more complex in the situation in which the avoid fallow and a continuous monoculture is performed. The results shown that around 40% of the area is subject to the regime of fallow while 60% have growing every year. In addition, another variation is detected if the year is humid (decrease of fallow) or dry (increase of fallow). The level of correlation between the drought damage ratios and cumulative NDVI for the cereal campaign obtained are classified according to their level of significance at 99, 95, 90 and 85%. Approximately half of the regions with high surface assurance have meaningful relationships. In the regions where no significant relationships are achieved several situations are discussed such as extreme situations in critical phenological periods that could have great influence on the final yields. Acknowledgements. This work was partially supported by ENESA under project P10 0220C-823.

Saa-Requejo, Antonio; Recuero, Laura; Palacios, Alicia; Díaz-Ambrona, Carlos G. H.; Tarquis, Ana M.



Effect of contact ratio on spur gear dynamic load  

NASA Technical Reports Server (NTRS)

A computer simulation is presented which shows how the gear contact ratio affects the dynamic load on a spur gear transmission. The contact ratio can be affected by the tooth addendum, the pressure angle, the tooth size (diametral pitch), and the center distance. The analysis presented was performed using the NASA gear dynamics code, DANST. In the analysis, the contact ratio was varied over the range 1.20 to 2.40 by changing the length of the tooth addendum. In order to simplify the analysis, other parameters related to contact ratio were held constant. The contact ratio was found to have a significant influence on gear dynamics. Over a wide range of operating speeds, a contact ratio close to 2.0 minimized dynamic load. For low contact ratio gears (contact ratio less than 2.0), increasing the contact ratio reduced the gear dynamic load. For high contact ratio gears (contact ratio = or greater than 2.0), the selection of contact ratio should take into consideration the intended operating speeds. In general, high contact ratio gears minimized dynamic load better than low contact ratio gears.

Liou, Chuen-Huei; Lin, Hsiang Hsi; Oswald, Fred B.; Townsend, Dennis P.



Inhibition to excitation ratio regulates visual system responses and behavior in vivo  

PubMed Central

The balance of inhibitory to excitatory (I/E) synaptic inputs is thought to control information processing and behavioral output of the central nervous system. We sought to test the effects of the decreased or increased I/E ratio on visual circuit function and visually guided behavior in Xenopus tadpoles. We selectively decreased inhibitory synaptic transmission in optic tectal neurons by knocking down the ?2 subunit of the GABAA receptors (GABAAR) using antisense morpholino oligonucleotides or by expressing a peptide corresponding to an intracellular loop of the ?2 subunit, called ICL, which interferes with anchoring GABAAR at synapses. Recordings of miniature inhibitory postsynaptic currents (mIPSCs) and miniature excitatory PSCs (mEPSCs) showed that these treatments decreased the frequency of mIPSCs compared with control tectal neurons without affecting mEPSC frequency, resulting in an ?50% decrease in the ratio of I/E synaptic input. ICL expression and ?2-subunit knockdown also decreased the ratio of optic nerve-evoked synaptic I/E responses. We recorded visually evoked responses from optic tectal neurons, in which the synaptic I/E ratio was decreased. Decreasing the synaptic I/E ratio in tectal neurons increased the variance of first spike latency in response to full-field visual stimulation, increased recurrent activity in the tectal circuit, enlarged spatial receptive fields, and lengthened the temporal integration window. We used the benzodiazepine, diazepam (DZ), to increase inhibitory synaptic activity. DZ increased optic nerve-evoked inhibitory transmission but did not affect evoked excitatory currents, resulting in an increase in the I/E ratio of ?30%. Increasing the I/E ratio with DZ decreased the variance of first spike latency, decreased spatial receptive field size, and lengthened temporal receptive fields. Sequential recordings of spikes and excitatory and inhibitory synaptic inputs to the same visual stimuli demonstrated that decreasing or increasing the I/E ratio disrupted input/output relations. We assessed the effect of an altered I/E ratio on a visually guided behavior that requires the optic tectum. Increasing and decreasing I/E in tectal neurons blocked the tectally mediated visual avoidance behavior. Because ICL expression, ?2-subunit knockdown, and DZ did not directly affect excitatory synaptic transmission, we interpret the results of our study as evidence that partially decreasing or increasing the ratio of I/E disrupts several measures of visual system information processing and visually guided behavior in an intact vertebrate. PMID:21795628

Shen, Wanhua; McKeown, Caroline R.; Demas, James A.



Comparison of Event Detection Methods for Centralized Sensor Networks  

NASA Technical Reports Server (NTRS)

The development of an Integrated Vehicle Health Management (IVHM) for space vehicles has become a great concern. Smart Sensor Networks is one of the promising technologies that are catching a lot of attention. In this paper, we propose to a qualitative comparison of several local event (hot spot) detection algorithms in centralized redundant sensor networks. The algorithms are compared regarding their ability to locate and evaluate the event under noise and sensor failures. The purpose of this study is to check if the ratio performance/computational power of the Mote Fuzzy Validation and Fusion algorithm is relevant compare to simpler methods.

Sauvageon, Julien; Agogiono, Alice M.; Farhang, Ali; Tumer, Irem Y.



Mixing properties of coaxial jets with large velocity ratios and large inverse density ratios  

NASA Astrophysics Data System (ADS)

An experimental study was conducted to better understand the mixing properties of coaxial jets as several parameters were systematically varied, including the velocity ratio, density ratio, and the Reynolds number. Diameters of the inner and outer jet were also varied. Coaxial jets are commonly used to mix fluids due to the simplicity of their geometry and the rapid mixing that they provide. A measure of the overall mixing efficiency is the stoichiometric mixing length (Ls), which is the distance along the jet centerline where the two fluids have mixed to some desired concentration, which was selected to be the stoichiometric concentration for H2/O2 and CH4/O2 in this case. For 56 cases, the profiles of mean mixture fraction, rms mixture fraction fluctuations (unmixedness), and Ls were measured using acetone planar laser induced fluorescence diagnostics. Results were compared to three mixing models. The entrainment model of Villermaux and Rehab showed good agreement with the data, indicating that the proper non-dimensional scaling parameter is the momentum flux ratio M. The work extends the existing database of coaxial jet scalar mixing properties because it considers the specific regime of large values of both the velocity ratio and the inverse density ratio, which is the regime in which rocket injectors operate. Also the work focuses on the mixing up to Ls where previous work focused on the mixing up to the end of the inner core. The Reynolds numbers achieved for a number of cases were considerably larger than previous gas mixing studies, which insures that the jet exit boundary conditions are fully turbulent.

Alexander Schumaker, S.; Driscoll, James F.



Transmission ratio control system for a continuously variable transmission  

SciTech Connect

This patent describes a control system for a continuously variable transmission for transmitting power of an internal combustion engine, the transmission having a drive pulley including a hydraulically shiftable first disc and a hydraulic cylinder for operating the disc, a driven pulley including a hydraulically shiftable second disc and a hydraulic cylinder for operating the second disc, and a belt engaged with both pulleys, the control system comprising a hydraulic circuit including a pump for supplying oil to both the hydraulic cylinders, a transmission ratio control valve including a shiftable spool for controlling the oil supplied to the cylinder of the drive pulley to change transmission ratio of the transmission to a desired transmission ratio, shifting means for shifting the spool, sensing means for sensing operating conditions of the engine and the transmission and for producing condition signals dependent on the conditions, actual transmission ratio signal producing means responsive to the condition signals for producing an actual transmission ratio signal corresponding to the actual transmission ratio of the transmission, desired transmision ratio signal producing means responsive to the condition signals for producing a desired transmission ratio signal corresponding to a desired transmission ratio, transmission ratio changing speed signal producing means responsive to the actual transmission ratio signal and to the desired transmission ratio signal for producing a transmission ratio changing rate signal corresponding to a transmission ratio changing rate, and control signal producing means responsive to the transmission ratio changing rate signal for producing a control signal for operating the shifting means to shift the spool dependent on the transmission ratio changing rate for changing the actual transmission ratio of the transmission to the desired transmission ratio.

Tanaka, H.



Study of Nuclear Stopping in Central Collisions at Intermediate Energies  

SciTech Connect

Nuclear stopping has been investigated in central nuclear collisions at intermediate energies by analyzing kinematically complete events recorded with the help of the 4{pi} multidetector INDRA for a large variety of symmetric systems. It is found that the mean isotropy ratio defined as the ratio of transverse to parallel momenta (energies) reaches a minimum near the Fermi energy, saturates or slowly increases depending on the mass of the system as the beam energy increases, and then stays lower than unity, showing that significant stopping is not achieved even for the heavier systems. Close to and above the Fermi energy, experimental data show no effect of the isospin content of the interacting system. A comparison with transport model calculations reveals that the latter overestimates the stopping power at low energies.

Lehaut, G. [LPC, CNRS/IN2P3, Ensicaen, Universite de Caen Basse Normandie, F-14050 Caen cedex (France); Universite de Lyon, Universite Lyon 1, CNRS-IN2P3, Institut de Physique Nucleaire de Lyon, F-69622 Villeurbanne (France); Durand, D.; Lopez, O.; Vient, E.; Bougault, R.; Le Neindre, N.; Parlog, M. [LPC, CNRS/IN2P3, Ensicaen, Universite de Caen Basse Normandie, F-14050 Caen cedex (France); Chbihi, A.; Frankland, J. D.; Bonnet, E. [GANIL, DSM-CEA/CNRS/IN2P3, F-14076 Caen cedex (France); Borderie, B.; Napolitani, P.; Rivet, M. F. [Institut de Physique Nucleaire, IN2P3-CNRS and Universite Paris-Sud, 91405 Orsay cedex (France); Galichet, E. [Institut de Physique Nucleaire, IN2P3-CNRS and Universite Paris-Sud, 91405 Orsay cedex (France); Conservatoire National des Arts et Metiers, F-75141 Paris (France); Guinet, D.; Lautesse, Ph. [Universite de Lyon, Universite Lyon 1, CNRS-IN2P3, Institut de Physique Nucleaire de Lyon, F-69622 Villeurbanne (France); Rosato, E. [Dipartimento di Scienze Fisiche e Sezione INFN, Universite di Napoli 'Federico II', I-80126 Napoli (Italy)



Role of taurine in the central nervous system  

PubMed Central

Taurine demonstrates multiple cellular functions including a central role as a neurotransmitter, as a trophic factor in CNS development, in maintaining the structural integrity of the membrane, in regulating calcium transport and homeostasis, as an osmolyte, as a neuromodulator and as a neuroprotectant. The neurotransmitter properties of taurine are illustrated by its ability to elicit neuronal hyperpolarization, the presence of specific taurine synthesizing enzyme and receptors in the CNS and the presence of a taurine transporter system. Taurine exerts its neuroprotective functions against the glutamate induced excitotoxicity by reducing the glutamate-induced increase of intracellular calcium level, by shifting the ratio of Bcl-2 and Bad ratio in favor of cell survival and by reducing the ER stress. The presence of metabotropic taurine receptors which are negatively coupled to phospholipase C (PLC) signaling pathway through inhibitory G proteins is proposed, and the evidence supporting this notion is also presented. PMID:20804583



CO Line Ratios in Nearby Galaxies  

NASA Astrophysics Data System (ADS)

We present a systematic analysis of low-J CO line excitation across the disks of 40 nearby, star forming galaxies. We combine the HERACLES survey of 12CO(2-1) emission conducted with the IRAM 30-m with the JCMT Nearby Galaxies Legacy Survey of 12CO(3-2) emission. These data are supplemented with archival 12CO(1-0) data from several facilities. We use a Bayesian formulation to robustly estimate the line ratios R21 = CO(2-1)/CO(1-0) and R32 = CO(3-2)/CO(2-1) in the presence of intrinsic scatter, non-detections, and a small fraction of unreliable data. We find that the canonical value of R21 = 0.7 only typifies galactic centers and that a value of R21 = 0.5 better typifies most galactic disks. We find R32 = 0.5 over a wide range of physical parameters with little change though R21 can vary more significantly. CO excitation is compared to local galactic properties. Of note, we find that star formation rate tracers are most clearly associated with higher values of R21 and R32.

Rosolowsky, Erik; Leroy, Adam K.; Usero, Antonio; Loeppky, Jason; Walter, Fabian; Wilson, Christine; Heracles Team, Ngls Team



A likelihood ratio test for nested proportions.  


For policy and medical issues, it is important to know if the proportion of an event changes after an intervention is administered. When the later proportion can only be calculated in a portion of the sample used to compute the previous proportion, the two proportions are nested. The motivating example for this work comes from the need to test whether admission rates in emergency departments are different between the first and a return visit. Here, subjects who contribute to the admission rate at the return visit must be included in the first rate and also return, but not vice versa. This conditionality means that existing methods, including the basic test of equality of two proportions, longitudinal data analysis methods, and recurrent event approaches are not directly applicable. Currently, researchers can only explore this question by the use of descriptive statistics. We propose a likelihood ratio test to compare two nested proportions by using the product of conditional probabilities. This test accommodates the conditionality, subject dependencies, and cluster effects and can be implemented in SAS PROC NLMIXED allowing for the proposed method to be readily used in an applied setting. Simulation studies showed that our approach provides unbiased estimates and reasonable power. Moreover, it generally outperforms the two-sample proportion z-test, in the presence of heterogeneity, and the Cochran-Mantel-Haenszel test. An example based on readmission rates through an emergency department is used to illustrate the proposed method. Copyright © 2014 John Wiley & Sons, Ltd. PMID:25394913

Chen, Yi-Fan; Yabes, Jonathan G; Brooks, Maria M; Singh, Sonia; Weissfeld, Lisa A



Large D/H variations in bacterial lipids reflect central metabolic pathways  

E-print Network

Large D/H variations in bacterial lipids reflect central metabolic pathways Xinning Zhanga , Aimee/H ratios. More impor- tantly, lipid/water D/H fractionations vary systematically with metabolism biogeo- chemical tool for linking lipids to energy metabolism, and would yield information that is highly

Sessions, Alex L.



Microsoft Academic Search

This paper deals with the effect of changing some design parameters on the performance of central-type jet pump when handling water. The parameters tested such as the area ratio between driving nozzle and mixing chamber, the distance between the driving nozzle exit and the beginning of the mixing chamber, the suction inlet shape, the suction nozzle semi cone angle and

I. A. EL-Sawaf


Supine Length, Weight and Head Circumference at Birth in Central Iran  

ERIC Educational Resources Information Center

Supine length, weight and head circumferences of 10,241 neonates (5241 boys, 5000 girls, sex ratio 105) born in Arak (central Iran) in 2004 are reported. The mean plus or minus standard deviation of boys' and girls' (p value for sex difference) supine length (mm), weight (g) and head circumference (mm) were estimated as 501 plus or minus 30 and…

Ayatollahi, S. M. T.; Rafiei, Mohammad



Isotopic composition of the precipitations in the central Mediterranean: Origin marks and orographic precipitation effects  

Microsoft Academic Search

The isotopic composition of the rainfall in northwestern Sicily (Italy, central Mediterranean) was investigated in the period February 2002 to March 2003. A rain gauge network was installed and sampled monthly. The monthly values of the D and 18O ratios showed a wide range that reflected seasonal climatic variations. Mean weighted values were used to define an isotopic model of

Marcello Liotta; Rocco Favara; Mariano Valenza



Non-existence of normal tokamak equilibria with negative central current G. W. Hammett,a)  

E-print Network

Non-existence of normal tokamak equilibria with negative central current G. W. Hammett,a) S. C-ratio expansion to show that normal magnetohydrodynamic equilibria with axisymmetric nested flux surfaces, non of the MHD equations indicates that a normal toroidal equilibrium is not possible if crosses through 0

Hammett, Greg


The Additive Effects of Differences in Central Tendency and Variability Are Important in Comparisons Between Groups  

Microsoft Academic Search

This article argues that the differences between 2 groups in means and variances must be examined together because left- and right-tail ratios (expressing group differences in proportions of low and high scores, respectively) are asymmetrical when distributions differ in both central tendency and dispersion. The point was illustrated by an analysis of tail effect sizes from the Differential Aptitude Tests,

Alan Feingold



p/pi Ratio in Di-Hadron Correlations  

E-print Network

Particle ratios are important observables used to constrain models of particle production in heavy-ion collisions. In this work we report on a measurement of the p/pi ratio in the transverse momentum range 2.0 p_{T,assoc} p_{T,trig} p/pi ratio in the bulk region is compatible with the p/pi ratio of an inclusive measurement, and is much larger than the p/pi ratio in the jet peak. The p/pi ratio in the jet peak is compatible with a PYTHIA reference, in which fragmentation in the vacuum is the dominant mechanism of particle production.

Misha Veldhoen; for the ALICE Collaboration



Primary Central Nervous System Lymphoma  

Microsoft Academic Search

\\u000a \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a Primary central nervous system lymphoma (PCNSL) is a rare malignancy that accounts for 2.5% of all brain tumors. This entity\\u000a can involve the eyes and the entire central nervous system (CNS).\\u000a \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a PCNSL presents with focal neurological deficits, neuropsychiatric symptoms, and increased intracranial pressure. Systemic\\u000a symptoms are uncommon.\\u000a \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a \\u000a The initial diagnosis is based on brain magnetic resonance imaging

Marnee M. Spierer; Evan M. Landau


Central exclusive production at RHIC  

NASA Astrophysics Data System (ADS)

The present status and future plans of the physics program of Central Exclusive Production (CEP) at RHIC are described. The measurements are based on the detection of the forward protons from the Double Pomeron Exchange (DPE) process in the Roman Pot system and of the recoil system of charged particles from the DPE process measured in the STAR experiment's Time Projection Chamber (TPC). The data described here were taken using polarized proton-proton collisions at ? {s} = 200 GeV. The preliminary spectra of two-pion mass reconstructed by STAR TPC in central region of pseudorapidity |?| < 1, are presented. Near future plans to take data with the current system at center-of-mass energy ? {s} = 200 GeV and plans to upgrade the forward proton tagging system are presented. Also a possible addition of the RPs to the sPHENIX detector is discussed.

Adamczyk, Leszek; Guryn, W?odek; Turnau, Jacek



Trace and minor element ratios in Halimeda aragonite from the Great Barrier Reef  

NASA Astrophysics Data System (ADS)

The calcareous green alga Halimeda can be a substantial contributor to aragonite sediment in reef ecosystems. In contrast to coral aragonite, little is known about the trace and minor element composition of Halimeda aragonite, so it is difficult to test oceanographic hypotheses about factors controlling its past growth. We investigated adapting trace element cleaning protocols for modern and Holocene Halimeda aragonite, modern and Holocene Halimeda trace and minor element compositions, and the potential utility of Halimeda aragonite for paleoceanographic investigations. We successfully adapted and applied sample treatment protocols developed for measuring trace elements in coral aragonite (generally less than 500 y old) to Halimeda aragonite (modern to approximately 5000 y old in this study). Modern Halimeda aragonite from John Brewer Reef in the Central GBR had mean Cd/Ca ratios of 5.19 ± 1.68 nmol/mol( ± 2? /sqrt n ) for Halimeda micronesica and 2.35 ± 0.38 nmol/mol for three closely related species important in bioherm accumulation Halimeda copiosa, Halimeda hederacea, and Halimeda opuntia. Mn/Ca ratios, with means from 89 239 nmol/mol for these four species, showed both intra-and inter-specific variability. Sr/Ca ratios (10.9 ± O.1 mmol/mol) and Mg/Ca ratios (1.35 ± 0.26 mmol/mol) were similar for all samples. Holocene Halimeda aragonite samples from cores of two bioherms in the northern GBR seemed well preserved on the basis of mineralogy and Sr/Ca and Mg/Ca ratios similar to those in modern Halimeda aragonite. Cd/Ca ratios (overall mean 0.96 ± 0.15 nmol/mol) were lower than those measured in the modern Halimeda from the central GBR location. However, Mn/Ca ratios in both cores were substantially higher than in modern Halimeda aragonite. While it may be possible to extract paleoceanographic information from Halimeda aragonite, substantial care is needed to evaluate and avoid the effects of post-depositional alteration.

Delaney, M. L.; Linn, L. J.; Davies, P. J.



The radial velocity, velocity dispersion, and mass-to-light ratio of the Sculptor dwarf galaxy  

NASA Technical Reports Server (NTRS)

The radial velocity, velocity dispersion, and mass-to-light ratio for 16 K giants in the Sculptor dwarf galaxy are calculated. Spectra at the Ca II triplet are analyzed using cross-correlation techniques in order to obtain the mean velocity of + 107.4 + or - 2.0 km/s. The dimensional velocity dispersion estimated as 6.3 (+1.1, -1.3) km/s is combined with the calculated core radius and observed central surface brightness to produce a mass-to-light ratio of 6.0 in solar units. It is noted that the data indicate that the Sculptor contains a large amount of mass not found in globular clusters, and the mass is either in the form of remnant stars or low-mass dwarfs.

Armandroff, T. E.; Da Costa, G. S.



Evidence for Central Regulation of Glucose Metabolism*  

PubMed Central

Evidence for central regulation of glucose homeostasis is accumulating from both animal and human studies. Central nutrient and hormone sensing in the hypothalamus appears to coordinate regulation of whole body metabolism. Central signals activate ATP-sensitive potassium (KATP) channels, thereby down-regulating glucose production, likely through vagal efferent signals. Recent human studies are consistent with this hypothesis. The contributions of direct and central inputs to metabolic regulation are likely of comparable magnitude, with somewhat delayed central effects and more rapid peripheral effects. Understanding central regulation of glucose metabolism could promote the development of novel therapeutic approaches for such metabolic conditions as diabetes mellitus. PMID:24142701

Carey, Michelle; Kehlenbrink, Sylvia; Hawkins, Meredith



Celtic Sites of Central Iberia  

NASA Astrophysics Data System (ADS)

This chapter concerns the astronomy practiced by Celtic peoples in some parts of central Iberia, specifically the Vetton and Celtiberian peoples, inhabitants of the so-called Late Iron Age. The construction of some elements of religion or worship was perfectly determined by geometry, topography, and especially astronomy, because their spatial orientation occurs in locations of great interest for maintaining the local calendar. The maintenance of this calendar was probably the primary objective of some of the elements studied.

Pérez Gutiérrez, Manuel


Central Venous Access for Chemotherapy  

Microsoft Academic Search

\\u000a Systemic chemotherapy is the cornerstone of modern day cancer treatment. Chemotherapeutic agents are often caustic solutions\\u000a that require large high flow venous channels for safe delivery; hence the need for central venous access. Chemotherapeutic\\u000a protocols vary greatly with respect to frequency, intensity, and duration. The concept of dose intensity is being scrutinized\\u000a with current trends favoring more frequent administration of

M. Andreas Mauro


Secondary Central Nervous System Lymphoma  

Microsoft Academic Search

This review summarizes current knowledge of secondary central nervous system lymphoma (SCNSL) in adults. We define SCNSL as\\u000a CNS involvement not obvious at the initiation of treatment for systemic lymphoma. Recently, polymerase chain reaction and\\u000a flow cytometry assays of cerebrospinal fluid have become available for the correct diagnosis of SCNSL. We reviewed reports\\u000a of patients treated without CNS prophylaxis to

Naoto Tomita; Fumio Kodama; Heiwa Kanamori; Shigeki Motomura; Yoshiaki Ishigatsubo



Primary central nervous system lymphomas  

Microsoft Academic Search

Opinion statement  Primary central nervous system lymphoma (PCNSL) is widely regarded as one of the primary brain tumors most amenable to treatment.\\u000a Although whole brain radiotherapy was the cornerstone of therapy for decades, recent work clearly indicates that chemotherapy\\u000a has become the primary focus of treatment for this disease. The initial treatment of PCNSL for all patients, including the\\u000a elderly, should

Lisa M. DeAngelis



Primary central nervous system lymphoma  

Microsoft Academic Search

Primary central nervous system lymphoma (PCNSL) is a rare variant of non-Hodgkin’s lymphoma that is increasing in incidence.\\u000a Methotrexate-based chemotherapy in combination with whole-brain radiotherapy (WBRT) has dramatically improved the outcome\\u000a of patients. However, treatmentrelated neurotoxicity is a significant complication, especially after radiotherapy in the elderly.\\u000a Despite advances in therapy, several important questions remain regarding optimal methotrexate dose, dosing frequency,

Igor T. Gavrilovic; Lauren E. Abrey



Primary central nervous system lymphoma  

Microsoft Academic Search

Opinion statement  There is no class I evidence for any therapeutic option in primary central nervous system lymphoma (PCNSL). When possible,\\u000a patients should be included in clinical trials. The role of surgery is restricted to stereotactic biopsy in order to gain\\u000a material for histopathologic diagnosis. Radiotherapy alone is associated with a median survival of no more than 1.5 years;\\u000a cure is

Hendrik Pels; Uwe Schlegel



Central Tendency: Mean, Mode, Median  

NSDL National Science Digital Library

This learning unit from Regents Exam Prep Center will help students learning to calculate mean, mode and median. The unit includes a lesson plan, practice examples, a teacher's guide and a worksheet. The term "measures of central tendency" is explained as finding the mean, median and mode of a set of data. The example of a set of test scores is used to demonstrate finding these measures. Links are also included which explain how to find these measurements using a graphing calculator.



[Pharmacotherapy of central oculomotor disorders].  


Nystagmus causes blurred vision due to oscillopsia, as well as impaired balance. Depending on etiology, additional cerebellar and brain stem signs may occur. We present the current pharmacotherapy of the most common forms of central nystagmus: downbeat nystagmus (DBN), upbeat nystagmus (UBN), acquired pendular nystagmus (APN), and congenital nystagmus (CGN). Recommended medical therapies are aminopyridines (4-AP) for DBN and UBN, gabapentin and memantine for CGN and APN, and baclofen for periodic alternating nystagmus (PAN). PMID:18633586

Kalla, R; Spiegel, R; Wagner, J; Rettinger, N; Jahn, K; Strupp, M



Central Asia Active Fault Database  

NASA Astrophysics Data System (ADS)

The ongoing collision of the Indian subcontinent with Asia controls active tectonics and seismicity in Central Asia. This motion is accommodated by faults that have historically caused devastating earthquakes and continue to pose serious threats to the population at risk. Despite international and regional efforts to assess seismic hazards in Central Asia, little attention has been given to development of a comprehensive database for active faults in the region. To address this issue and to better understand the distribution and level of seismic hazard in Central Asia, we are developing a publically available database for active faults of Central Asia (including but not limited to Afghanistan, Tajikistan, Kyrgyzstan, northern Pakistan and western China) using ArcGIS. The database is designed to allow users to store, map and query important fault parameters such as fault location, displacement history, rate of movement, and other data relevant to seismic hazard studies including fault trench locations, geochronology constraints, and seismic studies. Data sources integrated into the database include previously published maps and scientific investigations as well as strain rate measurements and historic and recent seismicity. In addition, high resolution Quickbird, Spot, and Aster imagery are used for selected features to locate and measure offset of landforms associated with Quaternary faulting. These features are individually digitized and linked to attribute tables that provide a description for each feature. Preliminary observations include inconsistent and sometimes inaccurate information for faults documented in different studies. For example, the Darvaz-Karakul fault which roughly defines the western margin of the Pamir, has been mapped with differences in location of up to 12 kilometers. The sense of motion for this fault ranges from unknown to thrust and strike-slip in three different studies despite documented left-lateral displacements of Holocene and late Pleistocene landforms observed near the fault trace.

Mohadjer, Solmaz; Ehlers, Todd A.; Kakar, Najibullah



The CDF Central Analysis Farm  

SciTech Connect

With Run II of the Fermilab Tevatron well underway, many computing challenges inherent to analyzing large volumes of data produced in particle physics research need to be met. We present the computing model within CDF designed to address the physics needs of the collaboration. Particular emphasis is placed on current development of a large O(1000) processor PC cluster at Fermilab serving as the Central Analysis Farm for CDF. Future plans leading toward distributed computing and GRID within CDF are also discussed.

Kim, T.H.; /MIT; Neubauer, M.; /UC, San Diego; Sfiligoi, I.; /Frascati; Weems, L.; /Fermilab; Wurthwein, F.; /UC, San Diego



Central Hyperthermia in Acute Stroke  

Microsoft Academic Search

Background: Central hyperthermia is an unresolved riddle; this study tries to define its characteristics. Methods: Seventy-four previously healthy patients who developed hyperthermia (?39°C) within 24 h after stroke onset were enrolled. The lesion sites, nature of stroke, and clinical features were studied. Results: Brainstem hemorrhage was the most common cause of hyperthermia (64%), followed by putamino-thalamus hemorrhage (24%), cerebellum hemorrhage

Chung-Yang Sung; Tsong-Hai Lee; Nai-Shin Chu



Rhyolite magmas of central America  

Microsoft Academic Search

True rhyolites are found in two contrasting occurrences in Central America: in recent obsidian domes in the basalt-rhyolite\\u000a association of southeastern Guatemala, and in late Tertiary ignimbrites in Honduras and adjacent parts of Nicaragua. Both\\u000a are on the inner side of the main volcanic axis in a region that is visibly underlain by older metamorphic and plutonic rocks.\\u000a They have

A. R. McBirney; D. F. Weill



Do individual-tree growth models correctly represent height:diameter ratios of Norway spruce and Scots pine?  

PubMed Central

Height:diameter ratios are an important measure of stand stability. Because of the importance of height:diameter ratios for forest management, individual-tree growth models should correctly depict height:diameter ratios. In particular, (i) height:diameter ratios should not exceed that of very dense stands, (ii) height:diameter ratios should not fall below that of open-grown trees, (iii) height:diameter ratios should decrease with increasing spacing, (iv) height:diameter ratios for suppressed trees should be higher than ratios for dominant trees. We evaluated the prediction of height:diameter ratios by running four commonly used individual-tree growth models in central Europe: BWIN, Moses, Silva and Prognaus. They represent different subtypes of individual-tree growth models, namely models with and without an explicit growth potential and models that are either distance-dependent (spatial) or distance-independent (non-spatial). Note that none of these simulators predict height:diameter ratios directly. We began by building a generic simulator that contained the relevant equations for diameter increment, height increment, and crown size for each of the four simulators. The relevant measures of competition, site characteristics, and stand statistics were also coded. The advantage of this simulator was that it ensured that no additional constraint was being imposed on the growth equations, and that initial conditions were identical. We then simulated growth for a 15- and 30-year period for Austrian permanent research plots in Arnoldstein and in Litschau, which represent stands at different age-classes and densities. We also simulated growth of open-grown trees and compared the results to the literature. We found that the general pattern of height:diameter ratios was correctly predicted by all four individual-tree growth models, with height:diameter ratios above that of open-grown trees and below that of very dense stands. All models showed a decrease of height:diameter ratios with age and an increase with stand density. Also, the height:diameter ratios of dominant trees were always lower than that of mean trees. Although in some cases the observed and predicted height:diameter ratios matched well, there were cases where discrepancies between observed and predicted height:diameter ratios would be unacceptable for practical management predictions. PMID:21151352

Vospernik, Sonja; Monserud, Robert A.; Sterba, Hubert



Saharan dust particle properties over the central Mediterranean  

NASA Astrophysics Data System (ADS)

AERONET sun photometer measurements performed at five different sites of the Central Mediterranean during strong Saharan dust outbreaks are used to characterize optical and physical properties of dust particles. Sun photometer retrievals are combined at two of the five sites with lidar observations. It is shown that at low aerosol optical depths (AODs) the dust particle properties are quite dependent on dust load and monitoring site location. Differences on retrieved particle properties reduce with increasing dust load. AERONET retrievals at AOD (440 nm) ? 0.6 are then used in this paper to characterize dust particles over the central Mediterranean basin leading to columnar averaged values of the real refractive index < n> = 1.5 ± 0.1, the imaginary refractive index < k> = 0.004 ± 0.002, the single scattering albedo < SSA> = 0.89 ± 0.03, and the Angstrom exponent < Å> = 0.2 ± 0.1. It is shown that Å represents the best marker to trace the temporal evolution of dust events. Volume size distributions show a dominant coarse mode peaking at 1.7-3 ?m. In particular, the average coarse mode that is centred at ? 2.2 ?m at Lampedusa, which is ˜200 km away from the northwest Africa coast, gets peaked at ? 1.7 ?m at Lecce, which is ˜800 km away. Lidar retrievals are used to characterize the vertical distribution of dust particles by the vertical profiles of the backscatter and extinction coefficients, the lidar ratio, and the depolarization ratio. Lidar retrievals show that over the Mediterranean basin, dust layers generally extend from 1 up to 6 km and that their vertical distribution can significantly change within a few hours. It is also shown that at high values of the AODs dust particles are characterized by lidar ratios spanning the 50-70 sr range and depolarization ratios larger than 30%.

Tafuro, A. M.; Barnaba, F.; De Tomasi, F.; Perrone, M. R.; Gobbi, G. P.



Double ratio of charmonia in p+Pb collisions at sqrt(s_NN)=5.02 TeV  

E-print Network

Based on a kinetic description of J/psi dissociation and production in an expanding quark-gluon plasma that is described by a 2+1 dimensional ideal hydrodynamics, we have studied the double ratio R_{p Pb}(psi')/R_{p Pb}(J/psi) of charmonia in p+Pb collisions at sqrt(s_NN)=5.02 TeV by including not only the cold nuclear matter effects but also the hot nuclear matter effects. We find that the double ratio of prompt charmonia is significantly suppressed in the most central collisions as a result of the hot nuclear matter effects.

Yunpeng Liu; Che Ming Ko; Taesoo Song



Oxidative ratio (OR) of UK peats  

NASA Astrophysics Data System (ADS)

The oxidative ratio (OR) is the amount of CO2 sequestered in the terrestrial biosphere for each mol of O2 produced. The OR governs the effectiveness of a terrestrial biome to mitigate the impact of anthropogenic CO2 emissions and it has been used to calculate the balance of terrestrial and oceanic carbon sinks across the globe. However, few studies have investigated the controls of the variability in OR. What factors affect OR - climate? Soil type? Vegetation type? N deposition? Land use? Land use change? Small shifts in OR could have important implications in the global partitioning of CO2 between the atmosphere, biosphere, and oceans. This study looks at peat soils (Histosols) from a series of sites representing a climatic transect across the UK. Duplicate peat cores were taken, along with samples of above-ground vegetation and litter, from sites in northern Scotland (Forsinard), southern Scotland (Auchencorth), northern England (Moor House; Thorne Moor) through the Welsh borders (Whixhall Moss) and Somerset levels (Westhay Moor) to Dartmoor and Bodmin Moor in the south west of England. Sub-samples of the cores were analysed for their CHNO concentrations using a Costech ECS 4010 Elemental combustion system. Using the method of Masiello et al. (2008), OR values could be calculated from these elemental concentrations. Initial results show that OR values of UK peats varied between 0.94 and 1.1 with a median value of 1.05 which similar to the median value of World soils but the range is at the more reduced end. There was significant variation between peat cores, even between peat cores on the same site and the peat showed significant reduction in OR with depth in the core.

Clay, G. D.; Worrall, F.; Masiello, C. A.



Sustaining volcanism in Central Kamchatka  

NASA Astrophysics Data System (ADS)

Flux-induced melting in the mantle wedge acts as the driving mechanism of arc volcanism in subduction zone environments. The primary control on the geographical position of arc volcanic centers is the depth of the subducting plate beneath the overriding plate. Globally, the average depth to the subducting plate beneath volcanic arcs is estimated at ˜100km. Volcanoes of the Central Kamchatka Depression in Eastern Russia comprise the most active volcanic arc system in the world with the depth of the subducting Pacific plate beneath the arc estimated at 180-200km, greatly in excess of the global average. In my research I attempt to describe the special tectonic circumstances that explain the deviation of the subduction depth constraint on arc volcanism in Central Kamchatka. In my study I rely on geophysical and geochemical data and petrological modeling to propose a new geodynamic model to explain voluminous volcanic activity in Central Kamchatka. In the initial stage of the study I conducted a geophysical investigation using receiver function methodology to map and describe the contact of the subducting Juan de Fuca Plate in the well-instrumented Cascadia subduction zone. I calculated and compiled a database of receiver function profiles from stations along the extent of the Cascadia forearc and mapped a low velocity anisotropic zone proposed to be serpentinized material along the forearc axis. In the second stage of my study I applied a similar methodology to describe the sub-crustal structure of Central Kamchatka. Results of this effort suggested presence of a low-velocity zone in the upper mantle separate from the subducting Pacific plate. I proceeded to investigate the tectonic origin of this feature in the final stage of my dissertation work with the use of receiver function migration, geochemical analysis and petrological modeling. I was able to further constrain the position of the low velocity anomaly and derive geochemical and petrological evidence linking the anomaly to a second source of melting driving volcanism of the Central Kamchatka arc.

Nikulin, Alex


Nonaxisymmetric high-aspect-ratio ellipsoids under shear: lowest-order correction for finite aspect ratios.  


We extend the classic study of the motion of small ellipsoidal particles under shear, focusing on simplifications obtained by considerations of the extreme aspect ratios typical of rheoscopic particles (e.g., Kalliroscope). Specifically, we study conditions under which the long-time behavior of scalene (i.e., triaxial or nonaxisymmetric) ellipsoids are well approximated by a model that is low order in the appropriate aspect ratios. After enumerating and describing the generic long-time motions of such particles in the lowest-order model, we investigate corrections induced by the physically appropriate lowest-order correction to the base model, with special attention to a periodic wobbling motion special to scalene ellipsoids. PMID:25122367

Shi, Feng; Mucha, Peter J



Rapid exchange effects on isotope ratios in groundwater systems: 2. Flow investigation using Sr isotope ratios  

NASA Astrophysics Data System (ADS)

Sr isotope ratios were measured in groundwater, whole rock digestions, and cation exchange extracts from a clay-rich groundwater system at Ernest O. Lawrence Berkeley National Laboratory and were used to constrain flow velocities and search for preferential flow paths. In the Orinda formation siltstone, 87Sr/86Sr increases strongly over tens of meters along presumed flow paths, indicating slow groundwater flow. Dissolved Sr is close to isotopic equilibrium with the exchangeable Sr in the clays, and the observed 87Sr/86Sr increase is interpreted as a cation exchange front moving slowly through the unit combined with dissolution of minerals with relatively high 87Sr/86Sr ratios. The data are inverted using a one-dimensional transport-dissolution-exchange model; the results indicate long-term average flow velocities of less than 0.2 m/yr which are consistent with 14C measurements. The data suggest a lack of strong preferential flow paths through this unit.

Johnson, Thomas M.; Depaolo, Donald J.



Nonaxisymmetric high-aspect-ratio ellipsoids under shear: Lowest-order correction for finite aspect ratios  

NASA Astrophysics Data System (ADS)

We extend the classic study of the motion of small ellipsoidal particles under shear, focusing on simplifications obtained by considerations of the extreme aspect ratios typical of rheoscopic particles (e.g., Kalliroscope). Specifically, we study conditions under which the long-time behavior of scalene (i.e., triaxial or nonaxisymmetric) ellipsoids are well approximated by a model that is low order in the appropriate aspect ratios. After enumerating and describing the generic long-time motions of such particles in the lowest-order model, we investigate corrections induced by the physically appropriate lowest-order correction to the base model, with special attention to a periodic wobbling motion special to scalene ellipsoids.

Shi, Feng; Mucha, Peter J.



The effect of a reciprocal peat transplant between two contrasting Central European sites on C cycling and C isotope ratios  

NASA Astrophysics Data System (ADS)

An 18-month reciprocal peat transplant experiment was conducted between two peatlands in the Czech Republic. Both sites were 100% Sphagnum-covered, with no vascular plants, and no hummocks and hollows. Atmospheric depositions of sulfur were up to 10 times higher at the northern site Velke jerabi jezero (VJJ), compared to the southern site Cervene blato (CB). Forty-cm deep peat cores, 10-cm in diameter, were used as transplants and controls in five replicates. Our objective was to evaluate whether CO2 and CH4 emissions from Sphagnum peat bogs are governed mainly by organic matter quality in the substrate, or by environmental conditions. Emission rates and ?13C values of CO2 and CH4 were measured in the laboratory at time t=18 months. All measured parameters converged to those of the host site, indicating that, at least in the short-term perspective, environmental conditions were a more important control of greenhouse gas emissions than organic carbon quality in the substrate. Since sulfate reducers outcompete methanogens, we hypothesized that the S-polluted site VJJ should have lower methane emissions than CB. In fact, the opposite was true, with significantly (p<0.01) higher methane emissions from VJJ. Additionally, as a first step in an effort to link C isotope composition of emitted gases and residual peat substrate, we determined whether multiple vertical ?13C profiles in peat agree. A high degree of within-site homogeneity in ?13C was found. When a specific vertical ?13C trend was seen in one peat core, the same trend was also seen in all the remaining peat cores from the wetland. The ?13C value increased downcore at both CB and VJJ. At VJJ, however, 20 cm below surface, a reversal to lower ?13C downcore was seen. Based on 210Pb dating, peat at 20-cm depth at VJJ was only 15 years old. Increasing ?13C values in VJJ peat accumulated between 1880-1990 could not be caused by assimilation of atmospheric CO2 gradually enriched in the light isotope 12C due to fossil fuel burning. Rather they were a result of a combination of isotope fractionations accompanying assimilation and mineralization of Sphagnum C. These isotope fractionations may record information about past changes in C storage in wetlands.

Novak, M.; Zemanova, L.; Buzek, F.; Jackova, I.; Adamova, M.; Komarek, A.; Vile, M. A.; Kelman Wieder, R.; Stepanova, M.




E-print Network

OF LAKE MICHIGAN By DONALD MRAZ, Fishery Biologiat Wisconsin Conservation Department, Madison, Wis from northwestern Lake Michigan proper. Records of age indicated unusual strength for only one year cla88-1943 which strongly dominated the 1948 sample from Lake Michigan and the 1949 sample from Green


Essays in monetary policy conduction and its effectiveness: monetary policy rules, probability forecasting, central bank accountability, and the sacrifice ratio  

E-print Network

, Gordon and King, 1982, and Romer and Romer, 1989). But what is the cost of those monetary policy tightening policies in the real world? In an effort to measure those costs and their possible determinants, several authors have estimated the sacrifice...

Gabriel, Casillas Olvera,



Processes affecting oxygen isotope ratios of atmospheric and ecosystem sulfate in two contrasting forest catchments in Central Europe  

SciTech Connect

Sulfate aerosols are harmful as respirable particles. They also play a role as cloud condensation nuclei and have radiative effects on global climate. A combination of {delta}{sup 18}O-SO{sub 4} data with catchment sulfur mass balances was used to constrain processes affecting S cycling in the atmosphere and spruce forests of the Czech Republic. Extremely high S fluxes via spruce throughfall and runoff were measured at Jezeri (49 and 80 kg S ha{sup -1} yr{sup -1}, respectively). The second catchment, Na Lizu, was 10 times less polluted. In both catchments, {delta}{sup 18}O-SO{sub 4} decreased in the following order: open-area precipitation {gt} throughfall {gt} runoff. The 180-SO{sub 4} values of throughfall exhibited a seasonal pattern at both sites, with maxima in summer and minima in winter. This seasonal pattern paralleled {delta}{sup 18}O-H{sub 2}O values, which were offset by -18{per_thousand}. Sulfate in throughfall was predominantly formed by heterogeneous (aqueous) oxidation of SO{sub 2}. Wet-deposited sulfate in an open area did not show systematic {delta}{sup 18}O-SO{sub 4} trends, suggesting formation by homogeneous (gaseous) oxidation and/or transport from large distances. The percentage of incoming S that is organically cycled in soil was similar under the high and the low pollution. High-temperature {sup 18}O-rich sulfate was not detected, which contrasts with North American industrial sites. 29 refs., 4 figs., 3 tabs.

Martin Novak; Myron J. Mitchell; Iva Jackova; Frantisek Buzek; Jana Schweigstillova; Lucie Erbanova; Richard Prikryl; Daniela Fottova [Czech Geological Survey, Prague (Czech Republic). Department of Geochemistry



The effect of a reciprocal peat transplant between two contrasting Central European sites on C cycling and C isotope ratios  

Microsoft Academic Search

An 18-month reciprocal peat transplant experiment was conducted between two peatlands in the Czech Republic. Both sites were 100% Sphagnum-covered, with no vascular plants, and no hummocks and hollows. Atmospheric depositions of sulfur were up to 10 times higher at the northern site Velke jerabi jezero (VJJ), compared to the southern site Cervene blato (CB). Forty-cm deep peat cores, 10-cm

M. Novak; L. Zemanova; F. Buzek; I. Jackova; M. Adamova; A. Komarek; M. A. Vile; R. Kelman Wieder; M. Stepanova



Direct Density Ratio Estimation with Dimensionality Reduction Masashi Sugiyama  

E-print Network

Direct Density Ratio Estimation with Dimensionality Reduction Masashi Sugiyama , Satoshi Hara for directly estimating the ratio of two probability density functions without going through density estimation such as non-stationarity adaptation, outlier detection, conditional density estima- tion, feature selection

Sugiyama, Masashi


ORIGINAL PAPER Carbon isotope ratio measurements of glyphosate  

E-print Network

ORIGINAL PAPER Carbon isotope ratio measurements of glyphosate and AMPA by liquid chromatography chromatography coupled to isotope ratio mass spectrometry. We demon- strate that this analysis can be carried out



E-print Network

BUILDING EFFECTIVENESS COMMUNICATION RATIOS FOR IMPROVED BUILDING LIFE CYCLE MANAGEMENT Elmer a performance-based strategy utilising building effectiveness communication ratios stored in Building performance. Clients of new facilities are presented with energy certificates which act as benchmarks


Ultra-short nacelles for low fan pressure ratio propulsors  

E-print Network

This thesis addresses the uncharted inlet and nacelle design space for low pressure ratio fans for advanced aeroengines. A key feature in low fan pressure ratio (FPR) propulsors with short inlets and nacelles is the increased ...

Peters, Andreas, Ph. D. Massachusetts Institute of Technology



Phylogenetic diversity in cadmium : phosphorus ratio regulation by marine phytoplankton  

E-print Network

Phylogenetic diversity in cadmium : phosphorus ratio regulation by marine phytoplankton Z. V Abstract We examined the effect of irradiance and growth rate on cadmium : phosphorus ratio in five species


30 CFR 36.44 - Maximum allowable fuel : air ratio.  

Code of Federal Regulations, 2010 CFR

...false Maximum allowable fuel : air ratio. 36.44...FOR PERMISSIBLE MOBILE DIESEL-POWERED TRANSPORTATION...44 Maximum allowable fuel : air ratio. (a...delivered to MSHA with the fuel-injection system adjusted by the...



Learning and Teaching Ratio and Proportion: Research Implications  

NSDL National Science Digital Library

This is a chapter describing the theory and lesson planning for teaching ratio and rate problems. The authors describe how students use reasoning about multiplication and division to solve ratio and rate problems.

Martha Gioielli



RESEARCH LETTERS waist/hip ratio accounted for only 18%. Waist/hip ratio  

E-print Network

/hip ratio are known and their effects can be estimated separately. In these conditions, body-mass index attractiveness M J Tovée, S Reinhardt, J L Emery, P L Cornelissen Evolutionary psychology suggests that a woman (15­19 kg/m2 ), normal (20­24 kg/m2 ), overweight (25­30 kg/m2 ), and obese ( 30 kg/m2 ). Within each

Cornelissen, Piers


Deep, Low Mass Ratio Overcontact Binary Systems. V. The Lowest Mass Ratio Binary V857 Herculis  

NASA Astrophysics Data System (ADS)

Charge-coupled device (CCD) photometric light curves in the B, V, and R bands of the complete eclipsing binary star V857 Her are presented. It is shown that the light curves of the W UMa-type binary are symmetric and of A type according to Binnendijk's classification. Our four epochs of light minimum along with others compiled from the literature were used to revise the period and study the period change. Weak evidence indicates that the orbital period of V857 Her may show a continuous increase at a rate of dP/dt=+2.90×10-7 days yr-1. The photometric parameters of the system were determined with the 2003 version of the Wilson-Devinney code. It is shown that V857 Her is a deep overcontact binary system with f=83.8%+/-5.1%. The derived mass ratio of q=0.06532+/-0.0002 suggests that it has the lowest mass ratio among overcontact binary systems. As the orbital period increases, the decrease of the mass ratio will cause it to evolve into a single rapidly rotating star when it meets the more familiar criterion that the orbital angular momentum be less than 3 times the total spin angular momentum. To understand the evolutionary state of the system, long-term photometric monitoring and spectroscopic observations will be required.

Qian, S.-B.; Zhu, L.-Y.; Soonthornthum, B.; Yuan, J.-Z.; Yang, Y.-G.; He, J.-J.



14th Annual Conference Central Eurasian  

E-print Network

-Society Relations Central Asian Military History Social Memory and The Material World Conceiving Tajikistan: Islam and the State in Central Asia Contemporary Higher Education in Kyrgyzstan and Tajikistan Past

Wisconsin at Madison, University of


Central Difference Formula in Numerical Analysis.  

ERIC Educational Resources Information Center

Describes numerical differentiation and the central difference formula in numerical analysis. Presents three computer programs that approximate the first derivative of a function utilizing the central difference formula. Analyzes conditions under which the approximation formula is exact. (MDH)

de Alwis, Tilak



Universidad Central de Venezuela Facultad de Ciencias  

E-print Network

Universidad Central de Venezuela Facultad de Ciencias Escuela de Computación Lecturas en Ciencias-02 Centro CCCT Caracas, Abril, 2007. #12;Universidad Central de Venezuela Facultad de Ciencias Escuela de

Raydan, Marcos


BioMed Central Page & of &2  

E-print Network

BioMed Central Page & of &2 (page number not for citation purposes) Reproductive Biology and Rapraeger; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution

Rapraeger, Alan C.


Ratio and group size in day care programs  

Microsoft Academic Search

Literature on the influences of ratio and group size on children's development in day care is reviewed. Relatively few studies are responsible for the widely held beliefs about the influence of ratio and group size on children's development. When measured separately, ratio and group size are sometimes, but not always related to children's development. Some significant relationships are not in

Loraine Dunn



Final Report on Isotope Ratio Techniques for Light Water Reactors  

SciTech Connect

The Isotope Ratio Method (IRM) is a technique for estimating the energy or plutonium production in a fission reactor by measuring isotope ratios in non-fuel reactor components. The isotope ratios in these components can then be directly related to the cumulative energy production with standard reactor modeling methods.

Gerlach, David C.; Gesh, Christopher J.; Hurley, David E.; Mitchell, Mark R.; Meriwether, George H.; Reid, Bruce D.



26 CFR 26.2642-1 - Inclusion ratio.  

Code of Federal Regulations, 2010 CFR

...into two portions. One portion is equal to...000) and has a zero inclusion ratio...applicable fraction is one ($2,000/$2...inclusion ratio is zero (1 ? 1 = 0). ...applicable fraction of zero (0/$2,000...inclusion ratio of one (1 ? 0 =...



Odds Ratio Estimation in Bernoulli Smoothing Spline ANOVA Models  

E-print Network

Odds Ratio Estimation in Bernoulli Smoothing Spline ANOVA Models Yuedong Wang \\Lambda Department the odds ratios based on a SS ANOVA model for binary data and construct Bayesian confidence in­ tervals. We intervals. Our simulations suggest that the odds ratio estimates are quite reasonable in general but may

Wang, Yuedong


ODDS, ODDS Ratios and Relative Risk What are ODDS?  

E-print Network

ODDS, ODDS Ratios and Relative Risk What are ODDS? Odds, like probability, contain the number it will not be drawn or 4 to 48 or 1:12. The odds in favor of an event or a proposition are expressed as the ratio odds, the ratio is implied, but never actually computed in its reduced form. Odds are expressed as "a

Priestley, Jennifer Lewis


An Estimate of the Odds Ratio That Always Exists  

E-print Network

An Estimate of the Odds Ratio That Always Exists Michael PARZEN , Stuart LIPSITZ, Joseph IBRAHIM, and Neil KLAR This article proposes an estimate of the odds ratio in a (2 £ 2) table obtained from studies estimate of the odds ratio which has such properties is obtained when adding .5 to each cell of the table

Parzen, Michael


Intransitive Likelihood-Ratio Classifiers Jeff Bilmes and Gang Ji  

E-print Network

-likelihood ratio and G @DB ¦PI4Q#R ! 7XYV`! 8 is the log prior odds. The strategy proceeds by evaluating 9aIntransitive Likelihood-Ratio Classifiers Jeff Bilmes and Gang Ji Department of Electrical In this work, we introduce an information-theoretic based correction term to the likelihood ratio

Washington at Seattle, University of


Determinants of Faculty Gender Ratios across Institutions and Departments.  

ERIC Educational Resources Information Center

Faculty gender ratios vary considerably across institutions, and past research has shown that certain characteristics of institutions have a significant effect on these gender ratios. Understanding the drivers of faculty gender ratio variation is important since the concentration of women in particular types of institutions contributes to gender…

Rajeswaren, Anita Nimi


Swirl ratio effects on tornado-like vortices  

Microsoft Academic Search

The effect of swirl ratio on the flow field for a tornado-like vortex simulator (TVS) is investigated. Different swirl ratios are obtained by changing the geometry and tangential velocity which determine the vortex evolution. Flow visualizations, surface pressure and Particle Image Velocimetry (PIV) measurements are performed in a small TVS for swirl ratios S between 0 and 1. The PIV

Pooyan Hashemi-Tari; Roi Gurka; Horia Hangen



3D Property Modeling of Void Ratio by Cokriging  

Microsoft Academic Search

Void ratio measures compactness of ground soil in geotechnical engineering. When samples are collected in certain area for mapping void ratios, other relevant types of properties such as water content may be also analyzed. To map the spatial distribution of void ratio in the area based on these types of point, observation data interpolation is often needed. Owing to the

Yao Lingqing; Pan Mao; Cheng Qiuming



Tax Ratios in Macroeconomics: Do Taxes Really Matter?  

Microsoft Academic Search

In various empirical studies so-called tax ratios (tax revenues expressed as a ratio of some aggregate tax base) are employed as approximations for tax burdens. The most difficult problem in calculating tax ratios is the way in which personal income tax revenues are attributed to labour and capital. We argue that the methodology of Mendoza et al. (1994) is seriously

Jan-Egbert Sturm; Jakob de Haan



Density Ratio Estimation: A New Versatile Tool for Machine Learning  

E-print Network

Density Ratio Estimation: A New Versatile Tool for Machine Learning Masashi Sugiyama Department based on the ratio of prob- ability densities has been proposed recently and gathers a great deal of attention in the machine learning and data mining communities [1­17]. This density ratio framework includes

Sugiyama, Masashi


Conditional Density Estimation via Least-Squares Density Ratio Estimation  

E-print Network

781 Conditional Density Estimation via Least-Squares Density Ratio Estimation Masashi Sugiyama a novel method of con- ditional density estimation. Our basic idea is to express the conditional density in terms of the ratio of unconditional densities, and the ratio is directly estimated without going through

Sugiyama, Masashi


Gyromagnetic ratio of rapidly rotating compact stars in general relativity  

E-print Network

Gyromagnetic ratio of rapidly rotating compact stars in general relativity J´er^ome Novak on the equilibrium of the fluid. This allows us to study the behaviour of the gyromagnetic ratio for those objects and incompressible fluid, we find that the gyromagnetic ratio is directly proportional to the compaction parameter M

Paris-Sud XI, Université de


Get the Correct Hazard Ratio from SAS ® PROC PHREG Procedure  

Microsoft Academic Search

Cox proportional hazards model is a commonly used model in providing hazard ratio to compare survival times of two population groups. The exponentiated linear regression part of the model describes the effects of explanatory variables on hazard ratio. PROC PHREG is a SAS procedure that implements the Cox model and provides the hazard ratio estimate. The estimate is interpreted as

Betty Ying Wang


DC-to-AC inverter ratio failure detector  

NASA Technical Reports Server (NTRS)

Failure detection technique is based upon input-output ratios, which is independent of inverter loading. Since inverter has fixed relationship between V-in/V-out and I-in/I-out, failure detection criteria are based on this ratio, which is simply inverter transformer turns ratio, K, equal to primary turns divided by secondary turns.

Ebersole, T. J.; Andrews, R. E.



Inheritance of progeny sex ratio in Urtica dioica  

Microsoft Academic Search

Seed samples collected from female Urtica dioica plants in the field showed considerable inter-family variation in the sex ratio (faction of males). To investigate the inheritance pattern of the sex ratio trait, crosses were performed between individual male and female plants from different sex ratio families. Our results suggest, at least for the families studied here, that maternal parents strongly




Distributed trace using central performance counter memory  


A plurality of processing cores, are central storage unit having at least memory connected in a daisy chain manner, forming a daisy chain ring layout on an integrated chip. At least one of the plurality of processing cores places trace data on the daisy chain connection for transmitting the trace data to the central storage unit, and the central storage unit detects the trace data and stores the trace data in the memory co-located in with the central storage unit.

Satterfield, David L.; Sexton, James C.



Enantiomer Ratios of Meteoritic Sugar Derivatives  

NASA Technical Reports Server (NTRS)

Carbonaceous meteorites contain a diverse suite of soluble organic compounds. Studies of these compounds reveal the Solar System's earliest organic chemistry. Among the classes of organic compounds found in meteorites are keto acids (pyruvic acid, etc.), hydroxy tricarboxylic acids (1), amino acids, amides, purines and pyrimidines. The Murchison and Murray meteorites are the most studied for soluble and insoluble organic compounds and organic carbon phases. The majority of (indigenous) meteoritic compounds are racemic, (i.e., their D/L enantiomer ratios are 50:50). However, some of the more unusual (non-protein) amino acids contain slightly more of one enantiomer (usually the L) than the other. This presentation focuses on the enantiomer analyses of three to six-carbon (3C to 6C) meteoritic sugar acids. The molecular and enantiomer analysis of corresponding sugar alcohols will also be discussed. Detailed analytical procedures for sugar-acid enantiomers have been described. Results of several meteorite analyses show that glyceric acid is consistently racemic (or nearly so) as expected of non-biological mechanisms of synthesis. Also racemic are 4-C deoxy sugar acids: 2-methyl glyceric acid; 2,4-dihydroxybutyric acid; 2,3-dihydroxybutyric acid (two diastereomers); and 3,4-dihydroxybutyric acid. However, a 4C acid, threonic acid, has never been observed as racemic, i.e., it possesses a large D excess. In several samples of Murchison and one of GRA 95229 (possibly the most pristine carbonaceous meteorite yet analyzed) threonic acid has nearly the same D enrichment. In Murchison, preliminary isotopic measurements of individual threonic acid enantiomers point towards extraterrestrial sources of the D enrichment. Enantiomer analyses of the 5C mono-sugar acids, ribonic, arabinonic, xylonic, and lyxonic also show large D excesses. It is worth noting that all four of these acids (all of the possible straight-chained 5C sugar acids) are present in meteorites, including the rare lyxonic acid, and their relative abundances are in equilibrium proportions. In addition (in contrast to the above D-only excesses), some of the above acids are found in biology as the L enantiomer. Whether rare are common, all of the 6C sugar acids that are present in sufficient amounts to allow enantiomer analysis (Mannonic, gluconic, altronic, talonic, idonic, gulonic, and galactonic) also, apparently, possess significant D excesses.

Cooper, George




PubMed Central

Congenital central hypoventilation syndrome (CCHS) patients show significant autonomic dysfunction in addition to the well-described loss of breathing drive during sleep. Some characteristics, e.g., syncope, may stem from delayed sympathetic outflow to the vasculature; other symptoms, including profuse sweating, may derive from overall enhanced sympathetic output. The dysregulation suggests significant alterations to autonomic regulatory brain areas. Murine models of the genetic mutations present in the human CCHS condition indicate brainstem autonomic nuclei are targeted; however, the broad range of symptoms suggests more widespread alterations. We used functional magnetic resonance imaging (fMRI) to assess neural response patterns to the Valsalva maneuver, an autonomic challenge eliciting a sequence of sympathetic and parasympathetic actions, in nine CCHS and 25 control subjects. CCHS patients showed diminished and time-lagged heart rate responses to the Valsalva maneuver, and muted fMRI signal responses across multiple brain areas. During the positive pressure phase of the Valsalva maneuver, CCHS responses were muted, but were less so in recovery phases. In rostral structures, including the amygdala and hippocampus, the normal declining patterns were replaced by increasing trends or more modest declines. Earlier onset responses appeared in the hypothalamus, midbrain, raphé pallidus, and left rostral ventrolateral medulla. Phase-lagged responses appeared in cerebellar pyramis and anterior cingulate cortex. The time-distorted and muted central responses to autonomic challenges likely underlie the exaggerated sympathetic action and autonomic dyscontrol in CCHS, impairing cerebral autoregulation, possibly exacerbating neural injury, and enhancing the potential for cardiac arrhythmia. PMID:20211704

Ogren, Jennifer A.; Macey, Paul M.; Kumar, Rajesh; Woo, Mary A.; Harper, Ronald M.



CASWW Dissertations in Central Asian Studies  

NSDL National Science Digital Library

Provided by the Harvard Forum for Central Asian Studies, this site will prove useful to graduate students and scholars of Central Asia. It currently contains information on approximately 250 recent dissertations in Central Asian Studies completed in universities worldwide. These are listed by author, institution, subject keywords, or in one of 25 major subject headings.



Microsoft Academic Search

While cities grow up, a need for instalation of one or several passenger transportation centrals is established. As these centrals gather different services as taxis, urban, suburban and intercity buses with other ground and air transport systems, noise generated by vehicles adds to that produced by comerce and services developed around the central. This noise affects drivers, transport controlers, passengers

IPN ESIME; México D. F. México


Network Centrality of Metro Systems Sybil Derrible*  

E-print Network

Network Centrality of Metro Systems Sybil Derrible* Future Urban Mobility Inter-Disciplinary Group. By applying the notion of betweenness centrality to 28 worldwide metro systems, the main goal of this paper Centrality of Metro Systems. PLoS ONE 7(7): e40575. doi:10.1371/journal.pone.0040575 Editor: Petter Holme

Illinois at Chicago, University of


Universidad Central de Venezuela Facultad de Ciencias  

E-print Network

Universidad Central de Venezuela Facultad de Ciencias Escuela de Computación Una herramienta para. Universidad Central de Venezuela. {ecoto, hnavarro, omaira} **Laboratorio TOOLS. Escuela de Computación. Facultad de Ciencias. Universidad Central de Venezuela. Caracas, Enero

Coto, Ernesto


Centralized Storm Information System (CSIS)  

NASA Technical Reports Server (NTRS)

A final progress report is presented on the Centralized Storm Information System (CSIS). The primary purpose of the CSIS is to demonstrate and evaluate real time interactive computerized data collection, interpretation and display techniques as applied to severe weather forecasting. CSIS objectives pertaining to improved severe storm forecasting and warning systems are outlined. The positive impact that CSIS has had on the National Severe Storms Forecast Center (NSSFC) is discussed. The benefits of interactive processing systems on the forecasting ability of the NSSFC are described.

Norton, C. C.



The MEANING multilingual central repository  

Microsoft Academic Search

This paper describes the first version of the Multilingual Central Repository,\\u000aa lexical knowledge base developed in the framework of the MEANING project.\\u000aCurrently the MCR integrates into the EuroWordNet framework five local wordnets\\u000a(including four versions of the English WordNet from Princeton), an upgraded version\\u000aof the EuroWordNet Top Concept ontology, the MultiWordNet Domains, the Suggested\\u000aUpper Merged Ontology

J. Atserias; L. Villarejo; G. Rigau; E. Agirre; J. Carroll; B. Magnini; P. Vossen



Elevated sacroilac joint uptake ratios in systemic lupus erythematosus  

SciTech Connect

Sacroiliac joint radiographs and radionuclide sacroiliac joint uptake ratios were obtained on 14 patients with active systemic lupus erythematosus. Elevated joint ratios were found unilaterally in two patients and bilaterally in seven patients when their lupus was active. In patients whose disease became quiescent, the uptake ratios returned to normal. Two patients had persistently elevated ratios with continued clinical and laboratory evidence of active lupus. Mild sacroiliac joint sclerosis and erosions were detected on pelvic radiographs in these same two patients. Elevated quantitative sacroiliac joint uptake ratios may occur as a manifestation of active systemic lupus erythematosus.

De Smet, A.A.; Mahmood, T.; Robinson, R.G.; Lindsley, H.B.



Molar optimization versus delayed reinforcement as explanations of choice between fixed-ratio and progressive-ratio schedules.  

PubMed Central

In a discrete-trials procedure, pigeons chose between a fixed-ratio 81 schedule and a progressive-ratio schedule by making a single peck at the key correlated with one or the other of these schedules. The response requirement on the progressive-ratio schedule began at 1 and increased by 10 each time the progressive-ratio schedule was chosen. Each time the fixed-ratio schedule was chosen, the requirement on the progressive-ratio schedule was reset to 1 response. In conditions where there was no intertrial interval, subjects chose the progressive-ratio schedule for an average of about five consecutive trials (during which the response requirement increased to 41), and then chose the fixed-ratio schedule. This ratio was larger than that predicted by an optimality analysis that assumes that subjects respond in a pattern that minimizes the response-reinforcer ratio or one that assumes that subjects respond in a pattern that maximizes the overall rate of reinforcement. In conditions with a 25-s or 50-s intertrial interval, subjects chose the progressive-ratio schedule for an average of about eight consecutive trials before choosing the fixed-ratio schedule. This change in performance with the addition of an intertrial interval was also not predicted by an optimality analysis. On the other hand, the results were consistent with the theory that choice is determined by the delays to the reinforcers delivered on the present trial and on subsequent trials. PMID:3681185

Mazur, J E; Vaughan, W



Focus on peripherally inserted central catheters in critically ill patients.  


Venous access devices are of pivotal importance for an increasing number of critically ill patients in a variety of disease states and in a variety of clinical settings (emergency, intensive care, surgery) and for different purposes (fluids or drugs infusions, parenteral nutrition, antibiotic therapy, hemodynamic monitoring, procedures of dialysis/apheresis). However, healthcare professionals are commonly worried about the possible consequences that may result using a central venous access device (CVAD) (mainly, bloodstream infections and thrombosis), both peripherally inserted central catheters (PICCs) and centrally inserted central catheters (CICCs). This review aims to discuss indications, insertion techniques, and care of PICCs in critically ill patients. PICCs have many advantages over standard CICCs. First of all, their insertion is easy and safe -due to their placement into peripheral veins of the arm- and the advantage of a central location of catheter tip suitable for all osmolarity and pH solutions. Using the ultrasound-guidance for the PICC insertion, the risk of hemothorax and pneumothorax can be avoided, as well as the possibility of primary malposition is very low. PICC placement is also appropriate to avoid post-procedural hemorrhage in patients with an abnormal coagulative state who need a CVAD. Some limits previously ascribed to PICCs (i.e., low flow rates, difficult central venous pressure monitoring, lack of safety for radio-diagnostic procedures, single-lumen) have delayed their start up in the intensive care units as common practice. Though, the recent development of power-injectable PICCs overcomes these technical limitations and PICCs have started to spread in critical care settings. Two important take-home messages may be drawn from this review. First, the incidence of complications varies depending on venous accesses and healthcare professionals should be aware of the different clinical performance as well as of the different risks associated with each type of CVAD (CICCs or PICCs). Second, an inappropriate CVAD choice and, particularly, an inadequate insertion technique are relevant-and often not recognized-potential risk factors for complications in critically ill patients. We strongly believe that all healthcare professionals involved in the choice, insertion or management of CVADs in critically ill patients should know all potential risk factors of complications. This knowledge may minimize complications and guarantee longevity to the CVAD optimizing the risk/benefit ratio of CVAD insertion and use. Proper management of CVADs in critical care saves lines and lives. Much evidence from the medical literature and from the clinical practice supports our belief that, compared to CICCs, the so-called power-injectable peripherally inserted central catheters are a good alternative choice in critical care. PMID:25374804

Cotogni, Paolo; Pittiruti, Mauro



Peripheral and central fatigue after muscle-damaging exercise is muscle length dependent and inversely related.  


Healthy untrained men performed 10 series of 12 knee eccentric extension repetitions (EE) at 160 degrees /s. The maximal voluntary isometric contraction force of the quadriceps muscle, the maximal rate of electrically induced torque development (RTD) and relaxation (RTR), isokinetic concentric torque at 30 degrees /s, the electrostimulation-induced torque at 20 and 100Hz frequencies were established before and after EE at shorter and longer muscle lengths. Besides, voluntary activation (VA) index and central activation ratio (CAR) were tested. There was more peripheral fatigue than central after EE. We established more central fatigue as well as low frequency fatigue at a shorter muscle length compared to the longer muscle length. Relative RTD as well as relative RTR, improved after EE and did not depend on the muscle length. Finally, central fatigue is inversely significantly related with the eccentric torque reduction during eccentric exercise and with the changes in muscle torque induced by low frequency stimulation. PMID:20347333

Skurvydas, Albertas; Brazaitis, Marius; Kamandulis, Sigitas; Sipaviciene, Saule



The initial mass ratio of solar type contact binaries  

NASA Astrophysics Data System (ADS)

The initial mass ratio distribution function, which gives the normalized number of binary objects formed at a given mass ratio, is computed for solar-type contact binaries (W UMa stars). The initial function is derived from the present mass ratio distribution function by integrating backwards in time based on a mass ratio evolution function describing the variation of the mass ratio with time since the coming into contact of the components, which is determined by the rate of angular momentum loss which is in turn determined by the total mass and mass ratio of the system. All contact binaries produced are found to exhibit initial mass ratios greater than 0.8, indicating that the components had nearly equal masses. Implications of the results for RS CVn stars are noted.

van t Veer, F.



Ratio maps of iron ore deposits Atlantic City district, Wyoming  

NASA Technical Reports Server (NTRS)

Preliminary results of a spectral rationing technique are shown for a region at the southern end of the Wind River Range, Wyoming. Digital ratio graymaps and analog ratio images have been produced for the test site, but ground truth is not yet available for thorough interpretation of these products. ERTS analog ratio images were found generally better than either ERTS single-channel images or high altitude aerial photos for the discrimination of vegetation from non-vegetation in the test site region. Some linear geological features smaller than the ERTS spatial resolution are seen as well in ERTS ratio and single-channel images as in high altitude aerial photography. Geochemical information appears to be extractable from ERTS data. Good preliminary quantitative agreement between ERTS-derived ratios and laboratory-derived reflectance ratios of rocks and minerals encourage plans to use lab data as training sets for a simple ratio gating logic approach to automatic recognition maps.

Vincent, R. K.



Consistent sex ratio bias of individual female dragon lizards  

PubMed Central

Sex ratio evolution relies on genetic variation in either the phenotypic traits that influence sex ratios or sex-determining mechanisms. However, consistent variation among females in offspring sex ratio is rarely investigated. Here, we show that female painted dragons (Ctenophorus pictus) have highly repeatable sex ratios among clutches within years. A consistent effect of female identity could represent stable phenotypic differences among females or genetic variation in sex-determining mechanisms. Sex ratios were not correlated with female size, body condition or coloration. Furthermore, sex ratios were not influenced by incubation temperature. However, the variation among females resulted in female-biased mean population sex ratios at hatching both within and among years. PMID:17148290

Uller, Tobias; Mott, Beth; Odierna, Gaetano; Olsson, Mats



Exploration potential of Central Europe  

SciTech Connect

Because of governmental changes an entire region of Central Europe has received exploration scrutiny not possible during the past 40-50 years. This entire area - Hungary, Czechoslovakia, Romania, Bulgaria, Yugoslavia, Albania, Poland, and East Germany - is tectonically related. Yugoslavia, although not under the same restrictions, is also considered in the same tectonic setting. Therefore, these countries can be expected to reflect some of the same stratigraphy, source rock, reservoir, trap and field types, and production history. Much of the region can be considered frontier while other parts mature. Production from all is about 55,000 T/D, 380,000 BO/D and 63.1 Bm{sup 3}/yr, 2,203 Bft{sup 3}/yr. Major source rocks have been identified as Tertiary-Oligocene, Miocene-Mesozoic, Triassic, Jurassic, and Cretaceous. Carboniferous coal sequences are considered source for the Permian. The East European platform and Tethyian plates are the foundation of the Central Europe states. Plate collisions during the late Mesozoic and into the Tertiary affected the Carpathian, Balkans, Dinarides, and Helenide Mountain chains. Mesozoic and Tertiary foredeep deposits have been proven productive from normal-, thrust-, and wrench-faulted anticlinal structures. Paleozoic, Mesozoic erosional remnants, and Tertiary lacustrine and deltaic stratigraphic deposits are the major productive reservoirs in the Pannonian basin. Permian shelf and reefal deposits are found in such areas as the Permian Shelf in Eastern Germany and Poland. Reefal plays may be found in Bulgaria and Romania offshore.

Krueger, W.C. (Amoco Production Co., Houston, TX (United States))



Geothermal initiatives in Central America  

SciTech Connect

The US Agency for International Development is supporting a new project in energy and resources exploitation for Central America. One of the largest components of the project involves exploration and reservoir development investigations directed at enhancing the production of electricity from the region's geothermal resources. An assessment of the geothermal resources of Honduras is in progress, and interesting geothermal regions in the Guanacaste Province of Costa Rica are being explored. Well-logging activities are in progress in the production wells at the Miravalles geothermal field in Costa Rica, and preparations are being made for logging critical wells at Ahuachapan in El Salvador. A self-contained logging truck, complete with high-temperature logging cable and logging tools designed for geothermal service, is being fabricated and will be made available for dedicated use throughout Central America. Geochemical and isotopic analyses of water samples collected in Panama are being evaluated to select a high-priority geothermal site in that country. Application of low- and medium-enthalpy geothermal fluids for industrial and agricultural processes is being investigated in Guatemala.

Hanold, R.J.; Loose, V.W.; Laughlin, A.W.; Wade, P.E.



Central vascular catheters and infections.  


Newborn infants in critical conditions require a permanent intra-venous line to allow for the administration of fluids, parenteral nutrition and drugs. The use of central venous catheters, however, is associated with an increased risk of infections, leading to prolongation of length of stay and higher hospitalization costs, particularly in extremely preterm infants. Dwell time is a significant factor for complications, with a predicted risk of catheter related infections of about 4 per 1000 catheter-days. To reduce the incidence of complications, several requirements must be met, including adequate staff and resources to provide education, training, and quality improvement programs, within a culture of communication and teamwork. Rigorous reporting schedule on line care and the implementation of unique bundle elements, the use of health care failure mode and effect analysis, the judicious use of antibiotics through an antimicrobial stewardship strategy, the application of specific antifungal prophylaxis are among the most effective interventions, while the addition of heparin to parenteral solution, or the use of antibiotic plus heparin lock therapy are under evaluation. Nursing assistance plays a fundamental role in managing central venous lines and in reducing or preventing the incidence of infection, by the application of several complex professional strategies. PMID:24709460

Dioni, Elisabetta; Franceschini, Renata; Marzollo, Roberto; Oprandi, Daniela; Chirico, Gaetano



Ratio of Trunk to Leg Volume as a New Body Shape Metric for Diabetes and Mortality  

PubMed Central

Background Body shape is a known risk factor for diabetes and mortality, but the methods estimating body shape, BMI and waist circumference are crude. We determined whether a novel body shape measure, trunk to leg volume ratio, was independently associated with diabetes and mortality. Methods Data from the National Health and Nutritional Examination Survey 1999–2004, a study representative of the US population, were used to generate dual-energy X-ray absorptiometry-derived trunk to leg volume ratio and determine its associations to diabetes, metabolic covariates, and mortality by BMI category, gender, and race/ethnicity group. Results The prevalence of pre-diabetes and diabetes increased with age, BMI, triglycerides, blood pressure, and decreased HDL level. After adjusting for covariates, the corresponding fourth to first quartile trunk to leg volume ratio odds ratios (OR) were 6.8 (95% confidence interval [CI], 4.9–9.6) for diabetes, 3.9 (95% CI, 3.0–5.2) for high triglycerides, 1.8 (95% CI, 1.6–2.1) for high blood pressure, 3.0 (95% CI, 2.4–3.8) for low HDL, 3.6 (95% CI, 2.8–4.7) for metabolic syndrome, and 1.76 (95% CI, 1.20–2.60) for mortality. Additionally, trunk to leg volume ratio was the strongest independent measure associated with diabetes (P<0.001), even after adjusting for BMI and waist circumference. Even among those with normal BMI, those in the highest quartile of trunk to leg volume ratio had a higher likelihood of death (5.5%) than those in the lowest quartile (0.2%). Overall, trunk to leg volume ratio is driven by competing mechanisms of changing adiposity and lean mass. Conclusions A high ratio of trunk to leg volume showed a strong association to diabetes and mortality that was independent of total and regional fat distributions. This novel body shape measure provides additional information regarding central adiposity and appendicular wasting to better stratify individuals at risk for diabetes and mortality, even among those with normal BMI. PMID:23874736

Wilson, Joseph P.; Kanaya, Alka M.; Fan, Bo; Shepherd, John A.



Effect of aspect ratio on the energy extraction efficiency of three-dimensional flapping foils  

NASA Astrophysics Data System (ADS)

Numerical simulations are used to investigate the effect of variation of the aspect ratio and the structure of pitching motions on the energy extraction efficiency and wake topology of flapping foils. The central aim is to predict the energy extraction performance and efficiency of a flapping-foil-based energy harvesting system (EHS) in realistic working conditions with finite aspect ratios. A sinusoidal heaving motion is imposed upon the foil, as well as both a sinusoidal pitching motion and a variety of trapezoidal-like periodic pitching motions. The simulations employ a finite-volume method with body-fitted moving grids, allowing the capture of flow structure near the foil surface. A detailed analysis of the hydrodynamic performance shows two peaks per periodic cycle in the lift force time histories or equivalently, the energy extraction time histories. The first primary peak corresponds to an effective angle of attack around 15.4°, indicating good attachment of the flow on the foil surface without significant flow separation. The secondary peak corresponds to a leading edge vortex (LEV) travelling on the foil surface. The shape of the LEV is altered markedly as the aspect ratio varies, and consequently the secondary peak in the lift force time history is strongly affected by the effects of three-dimensionality for foils with smaller aspect ratios. By examining the relationship between energy extraction efficiency and aspect ratio, a critical aspect ratio of AR = 4 is identified for sinusoidal pitching motions, below which the three-dimensional low-aspect-ratio characteristics dominate the flow evolution. Therefore, the compromise between higher energy extraction efficiency and lower costs of manufacturing and installation suggests that an aspect ratio around AR = 4 is the most appropriate choice for a real EHS. Furthermore, although trapezoidal-like pitching motions are known to improve the efficiency in flows restricted to two dimensions, particularly for non-optimal angle of attack, the efficiency of such flows is even more strongly affected by three-dimensional motions, with substantial efficiency loss even for AR = 8. This suggests that the implementation of efficiency improvement strategies obtained by two-dimensional studies should be treated with caution when extended to real three-dimensional flows.

Deng, Jian; Caulfield, C. P.; Shao, Xueming



Chernobyl fallout in southern and central Finland.  


To study the levels and distributions of radionuclides released in the Chernobyl accident, we sampled surface peat from 62 sites in Southern and Central Finland and measured 131I, 134Cs, 137Cs, 132Te, 140Ba, 103Ru, 90Sr, 141Ce, and 95Zr. The distribution of fallout activities was highly uneven, depending on movement of the contaminated air mass and rainfall distribution during the critical days. The highest values observed were 420 kBq m-2 of 131I and 70 kBq m-2 of 137Cs. The nuclide ratios showed wide and partly unexpected variations. The high-boiling-point, or nonvolatile, elements Ce and Zr were spread mostly on a 200-km-wide zone extending across Finland from southwest to northeast. The more volatile elements, I, Ce, and Te, showed quite a different, more widespread, fallout distribution, while an intermediate behavior was observed for Ba, Ru, and possibly Sr. These results can be explained by assuming that pulverized nuclear fuel material released in the reactor explosion on 26 April reached Finland via Poland and the Baltic Sea and traversed the country along the above-mentioned narrow zone, while volatile material, evaporated in the reactor fire from 26 April to 5 May, arrived in several waves and was consequently more widely and evenly spread. From their elemental melting and boiling points, Ru and Mo would appear to belong to the nonvolatile group and Sr to the volatile. Yet, their actual behaviors were opposite; Ru in particular was found in the nonvolatile as well as the volatile fallout, possibly because Ru activities were present in the fuel partly in the metallic state and partly as volatile oxides. PMID:1995514

Jantunen, M; Reponen, A; Kauranen, P; Vartiainen, M