Effect of litter type and perches on footpad dermatitis and hock burn in broilers housed at different stocking densities

The aim of the study was to assess the effect of litter type and environmental enrichment on the occurrence of footpad dermatitis and hock burns in broilers housed at low and high stocking densities. Chopped straw and sand were used as litter, and perches as environmental enrichment. Low and high stocking density implied 12 chickens/m2 and 20 chickens/m2, respectively. The study sample was divided into four groups of 50 birds, which were observed during a six-week fattening period. A significantly higher rate of severe footpad dermatitis was recorded in the group of chickens raised on sand at high stocking density, compared with low stocking density, whereas no significant difference was found between the groups of chickens raised on straw at different stocking densities. The rate of footpad dermatitis was also significantly higher in the group of chickens raised on sand at high stocking density, compared with chickens raised on straw at the same stocking density. There were no group differences in the occurrences of hock burns and perching. However, a significant negative correlation was recorded between perching and the occurrence of footpad dermatitis and hock burns. According to the occurrence of footpad dermatitis and hock burns, the study results suggested that chopped straw and sand were equally acceptable as litter for broilers, yet sand should be avoided at high stocking densities. There was no effect of stocking density and litter type on perching, but perches as a form of environmental enrichment proved efficient in reducing the rate of footpad dermatitis and hock burns.Keywords: chickens, contact dermatitis, environmental enrichment, housing, san

Crystal Structure of Citrobacter freundii Asp214Ala Tyrosine Phenollyase Reveals that Asp214 is Critical for Maintaining a Strain in the Internal Aldimine

Tyrosine phenol-lyase (TPL) is a pyridoxal-5′-phosphate (PLP) dependent enzyme which catalyzes β-elimination of L-tyrosine. In the holoenzyme the protonated pyridinium N1 atom of the PLP cofactor is hydrogen-bonded to the side chain of Asp214. Here we report the X-ray structure of C. freundii D214A TPL determined at 1.9 Å resolution. Comparison with the structure of the wild-type TPL shows that the D214A replacement induced significant conformational reorganization in the active site leading to its partial closure. Significantly, in D214A TPL the strain in the internal aldimine is completely released and the pyridine N1 atom of PLP is deprotonated. These observations explain the considerably reduced activity of the D214A TPL towards its substrates [T. V. Demidkina et al., Biochim. Biophys. Acta, Proteins Proteomics 1764 (2006) 1268–1276]. The reported structure reveals that Asp214 is critical for maintaining the strain in the internal aldimine. We argue that this strain is used by the enzyme to accelerate the transaldimination reaction, the first step in the enzymatic catalysis.(doi: 10.5562/cca1915

Usporedba korozijskih svojstava nekih zubnih slitina

In this paper corrosion resistance of experimental dental Co-Cr-X (X = Mo, Ni) alloys, high purity titanium and Ag-amalgam was studied in Ringer’s solution. On the basis of electrochemical measurements, the relevant indicator of general corrosion jcorr, which is used for ranking of materials, was determined. It was found that commercial alloy Wironit® is the most stable material followed by pure titanium, Co-Cr-Mo and Co-Cr-Ni alloys, while amalgam showed the lowest resistance in the experimental conditions of model oral cavity medium.U ovom radu ispitana je korozijska otpornost eksperimentalnih zubnih Co-Cr-X (X = Mo, Ni) slitina, titana i Ag-amalgama u Ringerovoj otopini. Na osnovi elektrokemijskih mjerenja određen je relevantni pokazatelj opće korozije jkor, koji se koristi za rangiranje materijala. Pokazalo se, da je korozijski najstabilnija komercijalna slitina Wironit®, koju slijede čisti titan, te Co-Cr-Mo i Co-Cr-Ni slitine, dok se amalgam pokazao najmanje otpornim u ispitnim uvjetima koji simuliraju medij usne šupljine

Effects of polymethylmethacrylate-transfer residues on the growth of organic semiconductor molecules on chemical vapor deposited graphene

Scalably grown and transferred graphene is a highly promising material for organic electronic applications, but controlled interfacing of graphene thereby remains a key challenge. Here, we study the growth characteristics of the important organic semiconductor molecule para-hexaphenyl (6P) on chemical vapor deposited graphene that has been transferred with polymethylmethacrylate (PMMA) onto oxidized Si wafer supports. A particular focus is on the influence of PMMA residual contamination, which we systematically reduce by H2 annealing prior to 6P deposition. We find that 6P grows in a flat-lying needle-type morphology, surprisingly independent of the level of PMMA residue and of graphene defects. Wrinkles in the graphene typically act as preferential nucleation centers. Residual PMMA does however limit the length of the resulting 6P needles by restricting molecular diffusion/attachment. We discuss the implications for organic device fabrication, with particular regard to contamination and defect tolerance.B.C.B acknowledges a College Research Fellowship from Hughes Hall, Cambridge. P.R.K. acknowledges the Lindemann Trust Fellowship. A.M. and G.R. acknowledge support by the Serbian MPNTR through Projects OI 171005 and III 45018. R.S.W. acknowledges a research fellowship from St. John’s College, Cambridge. S.H. acknowledges funding from EPSRC (GRAPHTED, Grant No. EP/K016636/1). We want to thank Dr. Sarah M. Skoff (Vienna University of Technology, Austria) for fruitful discussions.This is the author accepted manuscript. The final published version is available via AIP at http://scitation.aip.org/content/aip/journal/apl/106/10/10.1063/1.4913948

Synthesis of Anatase Nanopowders by Sol-gel Method and Influence of Temperatures of Calcination to Their Photocatalitic Properties

The titanium dioxide (TiO2) nanopowders were produced by sol-gel technique from tetrabutyl titanate as a precursor, varying the temperature of calcination (from 500 to 550 degrees C with the step of 10 degrees C). XRPD results have shown that all synthesized nanopowders are dominantly in anatase phase. The analysis of the shift and linewidth of the most intensive anatase E-g Raman mode confirmed the XRPD results and added the presence of small amount of highly disordered brookite phase in all samples. The analysis of pore structure from nitrogen sorption experimental data described all samples as mesoporous, with mean pore diameters in the range of 1.5 and 4.5 nm. Nanopowder properties have been related to the photocatalytic activity, tested in degradation of the textile dye (C.I. Reactive Orange 16). The sample calcined at temperature of 510 degrees C showed the best photocatalytic performance

Ukupna taložna tvar na području Primorsko-goranske županije u razdoblju 1975.-2008.

Dustfall measurements in Primorsko-goranska county started in 1975 in the Bakar Bay (Site 2 - Bakar and Site 3 - Kraljevica). The measurements were extended to the city of Rijeka (Site 1 - Rijeka) in 1982, to the nearby islands (Site 4 - Krk and Site 5 - Cres) in 1986, and inland to Gorski Kotar (Site 6 - Delnice and Site 7 - Lividraga) in 1995. This article brings the results of dustfall measurements from 1975 to 2008. Dustfall was low in the city, the nearby islands, and Gorski Kotar. Recommended and limit values were occasionally exceeded in the Bakar Bay due to emissions from the coke plant and harbour at Site 2 (1979-1997) and from the shipyard at Site 3. Lead content in the dustfall was below the national limits, save for two occasions at Site 2. Deposition of sulphur and nitrogen at the inland sites were below the respective critical load values.Ispitivanja ukupne taložne tvari u Primorsko-goranskoj županiji započela su 1975. godine na području Bakarskog zaljeva. Mjerenja su se 1982. god proširila na grad Rijeku, 1986. na otoke Krk i Cres, a 1995. i na područje Gorskog kotara. U radu su prikazani rezultati mjerenja ukupne taložne tvari u razdoblju 1975.-2008. na sedam odabranih postaja: u gradu Rijeci, dvije na području Bakarskog zaljeva (Bakar i Kraljevica), dvije na otocima (Krk i Cres) te dvije u Gorskom kotaru (Delnice i Lividraga). Analizirano je kretanje prosječnih godišnjih vrijednosti ukupno istaloženih tvari te u njima prisutnih količina sagorivog pepela, sulfata, nitrata, amonija i olova. Na području grada Rijeke, otoka Krka i Cresa te Gorskog kotara količina ukupne taložne tvari je niska. Količine ukupne taložne tvari povremeno su prelazile preporučenu graničnu vrijednost u Bakru (1979.-1994.), zbog emisija iz koksare i iz luke za rasuti teret te u Kraljevici, gdje se osamdesetih godina osjećao utjecaj koksare u Bakru, a od sredine devedesetih pojačani rad u brodogradilištu. Količine olova u taložnoj tvari su niske na svim postajama, osim povremenih skokova u Bakru, kada su prijeđene preporučene vrijednosti. Količine istaloženog sumpora i dušika na području Gorskog kotara ispod su odgovarajućih vrijednosti kritičnog opterećenja za ispitivana područja

A six-parameter space to describe galaxy diversification

Galaxy diversification proceeds by transforming events like accretion, interaction or mergers. These explain the formation and evolution of galaxies that can now be described with many observables. Multivariate analyses are the obvious tools to tackle the datasets and understand the differences between different kinds of objects. However, depending on the method used, redundancies, incompatibilities or subjective choices of the parameters can void the usefulness of such analyses. The behaviour of the available parameters should be analysed before an objective reduction of dimensionality and subsequent clustering analyses can be undertaken, especially in an evolutionary context. We study a sample of 424 early-type galaxies described by 25 parameters, ten of which are Lick indices, to identify the most structuring parameters and determine an evolutionary classification of these objects. Four independent statistical methods are used to investigate the discriminant properties of the observables and the partitioning of the 424 galaxies: Principal Component Analysis, K-means cluster analysis, Minimum Contradiction Analysis and Cladistics. (abridged)Comment: Accepted for publicationin A\&