721 research outputs found

    Value of beef performance records

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    "Individual performance records are useful for selecting superior performing cows and bulls and for culling undesirable animals from the herd. The Missouri Beef Cattle Improvement Programs are available to beef cattle breeders through local University of Missouri extension centers. · Flexibility of the programs helps both purebred and commercial breeders in their selection and breeding programs. The cow-calf man can use these programs as tools to check the performance of each animal from birth until it is added to the herd or slaughtered. By using these programs, you can evaluate an individual animal's genetic merit within a herd. This is important since new genes are not created and herd superiority comes from measuring economic traits and selecting genetically superior individuals."--First page.John W. Massey, James E. Ross, and D. W. Vogt (Department of Animal Science, College of Agriculture)Revised 2/85/8

    The nonlinear behaviour of shallow spherical shells

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    The subject matter of the thesis concerns the instability of shallow spherical shells. It presents an analytical and experimental investigation of the elastic, nonlinear, axisymmetric behavior of such shells under the action of uniform pressure and point loading at the apex. Chapter I is a critical survey of the relevant published literature. The survey cutlines the development of the theoretical aspects of shell buckling and shows how this was influenced by the results of experimental investigations. It further outlines the development of highly refined experimental techniques which reduced the scatter of results characteristics of previous work. It is then shown that even experimental work using these refined techniques, provides only a partial substantiation of theoretical analyses and it is concluded that the apparent disparity may be due to the uncertain character of the displacement dependent boundary restraints employed. In chapter II, the essential equivalence of the governing differential equations adopted by many nuthors is demonstrated for the first time in an integrated manner. The solutions of these equations: equations is discussed with special reference to an criginal analysis of the case of a pressure loaded, freely supported shell. Alternative solutions by direct integration and the Calerkin method are discussed but these are shown to lead to excessive computational difficulties. The effect of various boundary conditions is than examined and their influence on critical load values is shown to be significant. In the research undertaken, displacement dependent boundary conditions were avoided by using only force dependent conditions in the experimental work. The simplest of these conditions are those corresponding to a free support. In chapter III, the requirements of experimental techniques necessary to obtain the equilibrium path in both the stable and unstable states of equilibrium are discussed. This has led to the development of new techniques of preparation of accurate, stress free specimens and the adoption of a new, controlled deflection loading technique. the experimental investigation also presents, for the first time, the measurement of surface strains throughout the loading history of the shells. The results of the experimental investigations are discussed and compared with theory in Chapter IV. A critical comparison with the published experimental work of previous investigators is included where relevant. Chapter V summarises the main findings of the investigation regarding the basic aspects and shows that good agreement with theory is obtained by the refinement of experimental techniques introduced so as to approach as closely as possible, the assumptions of the theoretical analysis. Thus, for the first time to the author's knowledge, experimental results which are both consistent in them selves and in agreement with theory have been obtained. The application of the results of the investigation to practical engineering problems is considered. A Bibliography and Author's Index is provided in Chapter VI, followed in Chapter VII by Appendices giving details of analyses considered in the thesis, together with a full presentation of the results of the experimental investigation

    Analysis of the conversion of δ-(l-α-aminoadipoyl)-l-cysteinyl-d-α-aminobutyrate by active-site mutants of Aspergillus nidulans isopenicillin N synthase

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    AbstractBackground: Penicillins and cephalosporins constitute a major class of clinically useful antibiotics. A key step in their biosynthesis involves the oxidative cyclisation of δ-l-α-aminoadipoyl)-l-cysteinyl-d-valine to isopenicillin N by isopenicillin N synthase (IPNS). This chemically remarkable transformation has been extensively studied using substrate analogues. The conversion of an analogue in which the valine is replaced by a-aminobutyrate results in three products, two epimeric penams and a cepham. The ratio of these products in reactions catalysed by four different IPNS isozymes has been used previously to probe the thermicity of the chemical mechanism. But how IPNS restricts the products from the natural substrate to a single penam (isopenicillin N) has remained unknown.Results: A key active-site residue, Leu223, identified according to a model of enzyme-substrate binding, has been altered to sterically less demanding residues. As the steric constraints on the upper part of the active site are reduced, the ratio of the β-methyl penam to the cepham increases when the α-aminobutyrate-containing substrate analogue is used. These results suggest a mechanism for processing of the natural substrate in which IPNS uses steric control to restrict the conformational freedom of an intermediate such that the only product is the penam.Conclusions: Using steric pressure to control conformation, and hence to disfavour reactions leading to alternate products, is probably the result of evolutionary selection for a biologically active product at the expense of biologically inactive byproducts. It is likely that this sort of enzymatic catalysis is used in situations where substrate conversion is highly exothermic and a variety of products are possible

    239. Ocena efektu przeciwnowotworowego genetycznie modyfikowanej szczepionki komórkowej w mysim modelu raka nerki

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    CelGenetycznie modyfikowane szczepionki komórkowe (GMTV) mają za zadanie indukcję efektywnej odpowiedzi przeciwnowotworowej. Postanowiliśmy ocenić efekt protekcyjny dwóch różnych GMTV w mysim modelu raka jasnokomórkowego nerki, oraz rolę komórek dendrytycznych w fazie indukcji przeciwnowotworowej odpowiedzi komórkowej.MetodyPrzy wykorzystaniu wektorów retrowirusowych DCCMV-IRES-Neo-H-6 oraz DCCMV-IRES-Neo-IL-6 wprowadzono do komórek mysiego raka jasnokomórkowego (RenCa) skonstruowano dwa rodzaje GMTV: (i) Komórki RenCa wykazujące ekspresję genu Interleukiny-6, (ii) komórki RenCa wykazujące ekspresję genu Hyper-lnterleukiny-6 (sztuczna cytokina będąca białkiem fuzyjnym składającym się z IL-6 powiązanej sztucznym linkerem z agonistycznym rozpuszczalnym receptorem) W celu oceny efektu protekcyjnego GMTV, myszy Balb/c w wieku 8–12 tygodni (8 osobników w jednej grupie eksperymentalnej) immunizowano podając podskórnie w lewe udo, 1×10^6 naświetlonych (80 Gy) komórek (RenCa w/t, RenCa-IL-6, Renca-H6). Po 14 dniach myszom podawano podskórnie w prawe udo wyjściowe komórki RenCa w/t w ilości 5×10^5. Następnie oceniano dynamikę pojawiania się guzów oraz kinetykę ich wzrostu. W celu oceny mechanizmów indukcji odpowiedzi immunologicznej postanowiono ocenić in situ wpływ poszczególnych rodzajów GMTV na komórki dendrytyczne. Myszy Balb/c otrzymywały w okolicy śródbrzusza, podskórnie 2×10^6 napromienionych (80 Gy) komórek Renca w/t, Renca-IL-6, Renca H-6 zawieszonych w Matrigelu™. Po 7 dniach przy pomocy cytometru przepływowego analizowano komórki naciekające Matrigel.Wyniki i podsumowanieImmunizacja myszy komórkami RenCa-H6 okazała się najbardziej efektywna w porównaniu do komórek RenCa w/t i RenCa-IL-6. Jakkolwiek nie przeciwdziałała wzrostowi guzów. Aktywowane komórki DC naciekały najsilniej komórki RenCa-H6. Efekt protekcyjny wyraźnie korelował z ilością aktywowanych komórek DC naciekających miejsce podania GMTV. Intensywna infiltracja miejsca podania GMTV przez komórki DC o wysokim poziomie aktywacji wskazuje na silną role Hyper-Interleukiny-6 w procesie indukcji funkcjonalnej przeciwnowotworowej odpowiedzi immunologicznej

    Model- and calibration-independent test of cosmic acceleration

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    We present a calibration-independent test of the accelerated expansion of the universe using supernova type Ia data. The test is also model-independent in the sense that no assumptions about the content of the universe or about the parameterization of the deceleration parameter are made and that it does not assume any dynamical equations of motion. Yet, the test assumes the universe and the distribution of supernovae to be statistically homogeneous and isotropic. A significant reduction of systematic effects, as compared to our previous, calibration-dependent test, is achieved. Accelerated expansion is detected at significant level (4.3 sigma in the 2007 Gold sample, 7.2 sigma in the 2008 Union sample) if the universe is spatially flat. This result depends, however, crucially on supernovae with a redshift smaller than 0.1, for which the assumption of statistical isotropy and homogeneity is less well established.Comment: 13 pages, 2 figures, major change

    Theology, News and Notes - Vol. 23, No. 04

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    Theology News & Notes was a theological journal published by Fuller Theological Seminary from 1954 through 2014.https://digitalcommons.fuller.edu/tnn/1060/thumbnail.jp

    Klasifikacija dojki prema gustoći izborom značajki

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    Mammography as an x-ray method usually gives good results for lower density breasts while higher breast tissue densities significantly reduce the overall detection sensitivity and can lead to false negative results. In automatic detection algorithms knowledge about breast density can be useful for setting an appropriate decision threshold in order to produce more accurate detection. Because the overall intensity of mammograms is not directly correlated with the breast density we have decided to observe breast density as a texture classification problem. In this paper we propose breast density classification using feature selection process for different classifiers based on grayscale features of first and second order. In feature selection process different selection methods were used and obtained results show the improvement on overall classification by choosing the appropriate method and classifier. The classification accuracy has been tested on the mini-MIAS database and KBD-FER digital mammography database with different number of categories for each database. Obtained accuracy stretches between 97.2 % and 76.4 % for different number of categories.Mamografija je rendgenska metoda koja daje dobre rezultate pri slikanju dojki koje imaju manju gustoću, dok joj osjetljivost značajno opada pri snimanju dojki veće gustoće i time može doći do lažno pozitivnih rezultata. Poznavanje gustoće dojke može biti korisno kod algoritama za automatsku detekciju zbog mogućnosti određivanja praga odluke na osnovi tog znanja. S obzirom na to da ukupni intenzitet pojedinog mamograma nije izravno povezan s gustoćom, odlučili smo se promatrati gustoću kao problem klasifikacije teksture. U ovom radu predlažemo klasifikaciju dojki prema gustoći izborom izdvojenih značajki intenziteta prvog i drugog reda za različite klasifikatore. Za određivanje prikladnih značajki koristili smo različite metode i tako dobivene značajke pokazale su bolju točnost klasifikacije za odabrane klasifikatore. Točnost klasifikacije testirali smo na bazi mamografskih slika mini-MIAS i bazi digitalnih mamografskih slika KBD-FER s različitim brojem kategorija u koje su slike bile podijeljene. Postignuta točnost klasifikacije proteže se između 97,2 % i 76,4 % za različit broj kategorija u koje su mamogrami podijeljeni

    A BODIPY small molecule as hole transporting material for efficient perovskite solar cells

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    BODIPY-based materials are well known for their outstanding chemical and photo-stability as well as their ease of synthesis and tunability of their frontier molecular orbitals. These are attractive features for hole transporting materials (HTMs) for perovskite solar cells (PSCs) that could help improve device stability and cost. In this paper, we report the straightforward synthesis of a new BODIPY small molecule, PTZ-PTZ-BDP, functionalised with phenothiazine moieties in both the meso and α positions giving rise to a Y-shaped structure. As estimated by DFT calculations, and confirmed by electrochemical and ambient photoemission spectroscopy studies, PTZ-PTZ-BDP presents appropriate energy levels suitable for its use as a HTM in PSCs. Electrochemical measurements also reveal several redox processes with excellent reversibility. Systematic evaluation of its performance as HTM in n–i–p PSC with and without dopants was conducted and the device parameters compared with commonly used HTMs of spiro-OMeTAD and PTAA. The CH3NH3PbI3 based PSCs incorporating simple solution processed PTZ-PTZ-BDP as HTM demonstrated a champion power conversion efficiency of 14.6%, matched in performance and shelf-life stability to complex and expensive state-of-the-art HTMs, showing that BODIPY based HTMs are a promising direction for perovskite solar cells

    RhierBAPS: An R implementation of the population clustering algorithm hierBAPS [version 1; referees: 2 approved]

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    Identifying structure in collections of sequence data sets remains a common problem in genomics. hierBAPS, a popular algorithm for identifying population structure in haploid genomes, has previously only been available as a MATLAB binary. We provide an R implementation which is both easier to install and use, automating the entire pipeline. Additionally, we allow for the use of multiple processors, improve on the default settings of the algorithm, and provide an interface with the ggtree library to enable informative illustration of the clustering results. Our aim is that this package aids in the understanding and dissemination of the method, as well as enhancing the reproducibility of population structure analyses
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