Polymorphism of Genetic variability of gene in sheep

MUC1 gene encodes the polypeptide of a mucin present on the apical surface of the secreting mammary cells during lactation and on the surface of the milk fat globules (Mather, 2000). MUC1 contains a minisatellite region: the sequence, coding for the extracellular protein domain, consists mostly of a motif of 60 bp that in human, cattle and goat is tandemly repeated a variable number of times (VNTR polymorphism), giving rise to molecular variants of different size (Patton et al., 1995)

Casein haplotype structure in five Italian goat breeds

The aim of this work was to investigate the genetic structure of the casein gene cluster in 5 Italian goat breeds and to evaluate the haplotype variability within and among populations. A total of 430 goats from Vallesana, Roccaverano, Jonica, Garganica, and Maltese breeds were genotyped at alphas1-casein (CSN1S1), alphas2-casein, (CSN1S2), beta-casein (CSN2), and kappa-casein (CSN3) loci using several genomic techniques and milk protein analysis. Casein haplotype frequencies were estimated for each breed. Principal component analysis was carried out to highlight the relationship among breeds. Allele and haplotype distributions indicated considerable differences among breeds. The haplotype CSN1S1*F- CSN1S2*F-CSN3*D occurred in all breeds with frequencies >0.100 and was the most common haplotype in the Southern breeds. A high frequency of CSN1S1*0-CSN1S2*C-CSN3*A haplotype was found in Vallesana population (0.162). Principal component analysis clearly separated the Northern and Southern breeds by the first component. The variability of the caprine casein loci and variety of resulting haplotypes should be exploited in the future using specific breeding programs aiming to preserve biodiversity and to select goat genetic lines for specific protein production

Four-particle condensate in strongly coupled fermion systems

Four-particle correlations in fermion systems at finite temperatures are investigated with special attention to the formation of a condensate. Instead of the instability of the normal state with respect to the onset of pairing described by the Gorkov equation, a new equation is obtained which describes the onset of quartetting. Within a model calculation for symmetric nuclear matter, we find that below a critical density, the four-particle condensation (alpha-like quartetting) is favored over deuteron condensation (triplet pairing). This pairing-quartetting competition is expected to be a general feature of interacting fermion systems, such as the excition-biexciton system in excited semiconductors. Possible experimental consequences are pointed out.Comment: LaTeX, 11 pages, 2 figures, uses psfig.sty (included), to be published in Phys. Rev. Lett., tentatively scheduled for 13 April 1998 (Volume 80, Number 15

Policies to Regulate Distributed Data Exchange

This research is partially sponsored by the EPSRC grant EP/P011829/1, funded under the UK Engineering and Physical Sciences Council Human Dimensions of Cyber Security call (2016).Postprin

Are block copolymer worms more effective Pickering emulsifiers than block copolymer spheres?

RAFT-mediated polymerisation-induced self-assembly (PISA) is used to prepare six types of amphiphilic block copolymer nanoparticles which were subsequently evaluated as putative Pickering emulsifiers for the stabilisation of n-dodecane-in-water emulsions. It was found that linear poly(glycerol monomethacrylate)–poly(2-hydroxypropyl methacrylate) (PGMA–PHPMA) diblock copolymer spheres and worms do not survive the high shear homogenisation conditions used for emulsification. Stable emulsions are obtained, but the copolymer acts as a polymeric surfactant; individual chains rather than particles are adsorbed at the oil–water interface. Particle dissociation during emulsification is attributed to the weakly hydrophobic character of the PHPMA block. Covalent stabilisation of these copolymer spheres or worms can be readily achieved by addition of ethylene glycol dimethacrylate (EGDMA) during the PISA synthesis. TEM studies confirm that the resulting cross-linked spherical or worm-like nanoparticles survive emulsification and produce genuine Pickering emulsions. Alternatively, stabilisation can be achieved by either replacing or supplementing the PHPMA block with the more hydrophobic poly(benzyl methacrylate) (PBzMA). The resulting linear spheres or worms also survive emulsification and produce stable n-dodecane-in-water Pickering emulsions. The intrinsic advantages of anisotropic worms over isotropic spheres for the preparation of Pickering emulsions are highlighted. The former particles are more strongly adsorbed at similar efficiencies compared to spheres and also enable smaller oil droplets to be produced for a given copolymer concentration. The scalable nature of PISA formulations augurs well for potential applications of anisotropic block copolymer nanoparticles as Pickering emulsifiers

Building WF16: construction of a PPNA pisé structure in Southern Jordan

The Pre-Pottery Neolithic A (PPNA) period in Southwest Asia is essential for our understanding of the transition to sedentary, agricultural communities. Developments in architecture are key to understanding this transition, but many aspects of PPNA architecture remain elusive, such as construction techniques, the selection of building materials, and the functional use of space. The primary aim of the research described within this contribution was to build a PPNA-like structure in order to answer questions about PPNA architecture in general, while specifically addressing issues raised by the excavation of structures at the site of WF16, Southern Jordan. The second aim was to display a ‘PPNA’ building to visitors in Wadi Faynan to enhance their understanding of the period. The experimental construction based on one of the WF16 structures showed that 1) required materials can be acquired locally; 2) a construction technique using mud layers as described in this paper was likely used; 3) flat, or very slightly dome-shaped, roofs are functional and can also be used as a solid working platform; 4) the WF16 small semi-subterranean buildings appear inappropriate for housing a nuclear family unit

Detour and break optimising distance, a new perspective on transport and urbanism

International audienceFrom a discussion about the mathematical properties of metrics, we identify three fundamental characteristics of distance, which are optimality, detour and break. We then explore the implications of these properties for transport planning, urbanism and spatial planning. We state that distances contain the idea of optimum and that any distance is associated to a search for optimisation. Pedestrian movements obey this principle and sometimes depart from designed routes. Local sub-optimality conveyed by public transport maps has to be corrected by interventions on public space to relieve the load on central parts of networks. The second principle we state is that detour in distances is most often a means to optimise movement. Fast transport systems generates most of the detour observed in geographical spaces at regional scale. This is why detour has to be taken into account in regional transport policies. The third statement is that breaks in movement contribute to optimising distances. Benches, cafés, pieces of art, railway stations are examples of the urban break. These facilities of break represent an urban paradox: they organise the possibility of a break, of a waste of time in a trip, and they also contribute to optimising distances in a wider network. In that sense break should be considered as a relevant principle for the design of urban space in order to support a pedestrian oriented urban form

Preparation of double emulsions using hybrid polymer/silica particles: New pickering emulsifiers with adjustable surface wettability

A facile route for the preparation of water-in-oil-in-water (w/o/w) double emulsions is described for three model oils, namely, n-dodecane, isopropyl myristate, and isononyl isononanoate, using fumed silica particles coated with poly(ethylene imine) (PEI). The surface wettability of such hybrid PEI/silica particles can be systematically adjusted by (i) increasing the adsorbed amount of PEI and (ii) addition of 1-undecanal to the oil phase prior to homogenization. In the absence of this long-chain aldehyde, PEI/silica hybrid particles (PEI/silica mass ratio = 0.50) produce o/w Pickering emulsions in all cases. In the presence of 1-undecanal, this reagent reacts with the primary and secondary amine groups on the PEI chains via Schiff base chemistry, which can render the PEI/silica hybrid particles sufficiently hydrophobic to stabilize w/o Pickering emulsions at 20 °C. Gas chromatography, 1H NMR and X-ray photoelectron spectroscopy provide compelling experimental evidence for this in situ surface reaction, while a significant increase in the water contact angle indicates markedly greater hydrophobic character for the PEI/silica hybrid particles. However, when PEI/silica hybrid particles are prepared using a relatively low adsorbed amount of PEI (PEI/silica mass ratio = 0.075) only o/w Pickering emulsions are obtained, since the extent of surface modification achieved using this Schiff base chemistry is insufficient. Fluorescence microscopy and laser diffraction studies confirm that highly stable w/o/w double emulsions can be achieved for all three model oils. This is achieved by first homogenizing the relatively hydrophobic PEI/silica hybrid particles (PEI/silica mass ratio = 0.50) with an oil containing 3% 1-undecanal to form an initial w/o emulsion, followed by further homogenization using an aqueous dispersion of relatively hydrophilic PEI/silica particles (PEI/silica mass ratio = 0.075). Dye release from the internal aqueous cores into the aqueous continuous phase was monitored by visible absorption spectroscopy. These studies indicate immediate loss of 12-18% dye during the high speed homogenization that is required for double emulsion formation, but no further dye release is observed at 20 °C for at least 15 days thereafter

Crystal Structure of the PAC1R Extracellular Domain Unifies a Consensus Fold for Hormone Recognition by Class B G-Protein Coupled Receptors

Pituitary adenylate cyclase activating polypeptide (PACAP) is a member of the PACAP/glucagon family of peptide hormones, which controls many physiological functions in the immune, nervous, endocrine, and muscular systems. It activates adenylate cyclase by binding to its receptor, PAC1R, a member of class B G-protein coupled receptors (GPCR). Crystal structures of a number of Class B GPCR extracellular domains (ECD) bound to their respective peptide hormones have revealed a consensus mechanism of hormone binding. However, the mechanism of how PACAP binds to its receptor remains controversial as an NMR structure of the PAC1R ECD/PACAP complex reveals a different topology of the ECD and a distinct mode of ligand recognition. Here we report a 1.9 Å crystal structure of the PAC1R ECD, which adopts the same fold as commonly observed for other members of Class B GPCR. Binding studies and cell-based assays with alanine-scanned peptides and mutated receptor support a model that PAC1R uses the same conserved fold of Class B GPCR ECD for PACAP binding, thus unifying the consensus mechanism of hormone binding for this family of receptors