Silk hydrogels for tissue engineering

Silk hydrogels have been highlighted in the past decade as potential matrices for tissue engineering and regenerative medicine applications. In this mini review, the biological attributes of silk proteins, as well as methods reported in literature to fabricate silk hydrogels will be discussed.info:eu-repo/semantics/publishedVersio

Suppressed Coherence due to Orbital Correlations in the Ferromagnetically Ordered Metallic Phase of Mn Compounds

Small Drude weight $D$ together with small specific heat coefficient $\gamma$ observed in the ferromagnetic phase of R$_{1-x}$A$_x$MnO$_3$ (R=La, Pr, Nd, Sm; A=Ca, Sr, Ba) are analyzed in terms of a proximity effect of the Mott insulator. The scaling theory for the metal-insulator transition with the critical enhancement of orbital correlations toward the staggered ordering of two $e_g$ orbitals such as $3x^2-r^2$ and $3y^2-r^2$ symmetries may lead to the critical exponents of $D \propto \delta^{u}$ and $\gamma \propto \delta^v$ with $u=3/2$ and $v=0$. The result agrees with the experimental indications.Comment: 4 pages LaTeX using jpsj.sty. To appear in J. Phys. Soc. Jpn. 67(1998)No.

New Zealand Pastoral Systems: A Current Perspective

New Zealand\u27s diverse grassland resource of 13.5 M ha of permanent pasture, tussock or alpine grasslands underpin an intensive pastoral industry worth NZ$13 billion in 2004. The pastoral industry involves 37,000 farmers and a service industry of about 215,000 persons. It produces 27 M prime export lambs and 180,000 t of predominantly crossbred wool from 40 M ewes; 13 B litres of milk from 5.2 M dairy cattle; 800,000 t of beef from 4.7 M beef cattle and 33,000 t of venison from 2 M deer. Pastures and forage crops, mostly non- irrigated, are grazed \u27in situ\u27 by animals through controlled grazing management. The emphasis is on optimising utilisation at each grazing without penalising feed intake, pasture regrowth or persistance. Stocking rate and feed budgeting, along with a flexible stock trading policy are used to match animal demands with seasonal fluctuations in forage supply. The timing and duration of mating are varied to match anticipated seasonal growth. In dairy farming more condensed calving patterns have assisted in extending lactation length

QuickSNP: an automated web server for selection of tagSNPs

Although large-scale genetic association studies involving hundreds to thousands of SNPs have become feasible, the associated cost is substantial. Even with the increased efficiency introduced by the use of tagSNPs, researchers are often seeking ways to maximize resource utilization given a set of SNP-based gene-mapping goals. We have developed a web server named QuickSNP in order to provide cost-effective selection of SNPs, and to fill in some of the gaps in existing SNP selection tools. One useful feature of QuickSNP is the option to select only gene-centric SNPs from a chromosomal region in an automated fashion. Other useful features include automated selection of coding non-synonymous SNPs, SNP filtering based on inter-SNP distances and information regarding the availability of genotyping assays for SNPs and whether they are present on whole genome chips. The program produces user-friendly summary tables and results, and a link to a UCSC Genome Browser track illustrating the position of the selected tagSNPs in relation to genes and other genomic features. We hope the unique combination of features of this server will be useful for researchers aiming to select markers for their genotyping studies. The server is freely available and can be accessed at the URL http://bioinformoodics.jhmi.edu/quickSNP.pl

Survey of whistler mode chorus intensity at Jupiter

Whistler mode chorus emission is important in the acceleration of electrons and filling of the radiation belts at Jupiter. In this work chorus magnetic intensity levels (frequency-integrated spectral density, PB) at Jupiter are comprehensively binned and parameterized. The frequency range of chorus under study extends from the lower hybrid frequency, flh, to fceq/2 and fceq/2 < f < 0.8 fceq, where fceq is the cyclotron frequency mapped to the magnetic equator. The goal is to obtain a quantized distribution of magnetic intensity for use in stochastic modeling efforts. Parametric fits of magnetic plasma wave intensity are obtained, including PB versus frequency, latitude, and L shell. The results indicate that Jupiter chorus occurrence probability and intensity are higher than those at Saturn, reaching values observed at Earth. Jovian chorus is observed over most local times, confined primarily to the range 8 < L < 15, outside the high densities of the Io torus. The largest intensity levels are seen on the dayside; however, the sampling of chorus on the nightside is much less than on the dayside. Peak intensities occur near the equator with a weak dependence on magnetic latitude, λ. We conclude that Jovian chorus average intensity levels are approximately an order of magnitude lower than those at Earth. In more isolated regions the intensities are comparable to those observed at Earth. The spatial range of the chorus emissions extends beyond that assumed in previous Jovian global diffusive models of wave-particle electron acceleration

Engineering of a complex bone tissue model with endothelialised channels and capillary-like networks

In engineering of tissue analogues, upscaling to clinically-relevant sized constructs remains a significant challenge. The successful integration of a vascular network throughout the engineered tissue is anticipated to overcome the lack of nutrient and oxygen supply to residing cells. This work aimed at developing a multiscale bone-tissue-specific vascularisation strategy. Engineering pre-vascularised bone leads to biological and fabrication dilemmas. To fabricate channels endowed with an endothelium and suitable for osteogenesis, rather stiff materials are preferable, while capillarisation requires soft matrices. To overcome this challenge, gelatine-methacryloyl hydrogels were tailored by changing the degree of functionalisation to allow for cell spreading within the hydrogel, while still enabling endothelialisation on the hydrogel surface. An additional challenge was the combination of the multiple required cell-types within one biomaterial, sharing the same culture medium. Consequently, a new medium composition was investigated that simultaneously allowed for endothelialisation, capillarisation and osteogenesis. Integrated multipotent mesenchymal stromal cells, which give rise to pericyte-like and osteogenic cells, and endothelial-colony-forming cells (ECFCs) which form capillaries and endothelium, were used. Based on the aforementioned optimisation, a construct of 8 × 8 × 3 mm, with a central channel of 600 µm in diameter, was engineered. In this construct, ECFCs covered the channel with endothelium and osteogenic cells resided in the hydrogel, adjacent to self-assembled capillary-like networks. This study showed the promise of engineering complex tissue constructs by means of human primary cells, paving the way for scaling-up and finally overcoming the challenge of engineering vascularised tissues

Distributing CV entanglement over 4 co-propagating orthogonal modes

We propose a scheme for distributing continuous variable entanglement originally established among a pair of mode between a set of four orthogonal co-propagating modes. This is accomplished by exploiting the possibility of coupling polarization with optical angular momentum provided by the q-plate. Here we present the principle of the proposed scheme with a short feasibility study that shows that the four-modes covariance matrix at the scheme output represent an entangled multi mode system.Comment: 8 pages, 1 figur

Survey of Saturn Z-mode Emission

Because of the role of Z-mode emission in the diffusive scattering and resonant acceleration of electrons, we conduct a survey of intensity in the Saturn inner magnetosphere. Z-mode is primarily observed as “5 kHz” narrowband emission in the lower density regions where the ratio of cyclotron to plasma frequency, fc/fp > 1 to which we limit this study. This occurs at Saturn along the inner edge of the Enceladus torus near the equator and at higher latitudes. We present profiles and parametric fits of intensity as a function of frequency, radius, latitude, and local time. The magnetic field intensity levels are lower than chorus, but the electric field intensities are comparable. We conclude that Z-mode wave-particle interactions may make a significant contribution to electron acceleration in the inner magnetosphere of Saturn, supplementing acceleration produced by chorus emission

Observation of anomalous single-magnon scattering in half-metallic ferromagnets by chemical pressure control

Temperature variation of resistivity and specific heat have been measured for prototypical half-metallic ferromagnets, R_0.6Sr_0.4MnO_3, with controlling the one-electron bandwidth W. We have found variation of the temperature scalings in the resistivity from T^2 (R = La, and Nd) to T^3 (R = Sm), and have interpreted the $T^3-law in terms of the anomalous single-magnon scattering (AMS) process in the half-metallic system.Comment: To appear in Phys. Rev. Lett., 3 pages + 4 EPS figure