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Aerogels have been considered to be revolutionary solid-state materials due to their highly porous structure, low density, large surface area, and low thermal conductivity, which can be applied in the many modern fields of industry.

BACKGROUND Hydrodeoxygenation (HDO) of Chlorella algal oil extracted with supercritical hexane and stearic acid as a model compound was investigated over several supported Ni and Mo2N–MoO2 catalysts in a semibatch reactor at 300 °C under 30 bar in the presence of hydrogen. RESULTS The results showed that all catalysts were very active in HDO of stearic acid. With crude algal oil, a maximum conversion of lipids of 35% was found with an acidic Ni-HY-80 zeolite catalyst after 360 min. The main products in algal oil HDO were fatty acids; whereas maximally only 7% hydrocarbons were formed with Ni-HY-80. The main hydrocarbon products were formed via decarbonylation, as the hydrogenation/dehydration route was suppressed. CONCLUSIONS Hydrodeoxygenation of crude Chlorella algal oil was demonstrated over nickel supported on beta zeolite and with a molybdenum oxide–nitride catalyst. Strong catalyst deactivation occurred for the former catalyst, whereas the latter retained its activity. © 2016 Society of Chemical Industry

A 2 × 2 factorial experiment was conducted to assess the effects of presence or absence of rumen protozoa and of dietary coconut oil distillate (COD) supplementation on rumen fermentation characteristics, digesta kinetics and methane production in Brahman heifers. Twelve Brahman heifers were selected to defaunate, with 6 being subsequently refaunated. After defaunation and refaunation, heifers were randomly allocated to COD supplement or no supplement treatments while fed an oaten chaff-based diet. Methane production (MP; 94.17 v 104.72 g CH4 /d) and methane yield [MY; 19.45 v 21.64 g CH4 /kg dry matter intake (DMI)] were reduced in defaunated heifers compared with refaunated heifers when measured at 5 weeks after refaunation treatment (p 0.05). The results confirmed that defaunation and COD independently reduced enteric MP even though the reduced emissions were achieved without altering rumen fermentation VFA levels or gut digesta kinetics.

Two experiments were conducted assessing the effects of presence or absence of rumen protozoa and dietary nitrate addition on rumen fermentation characteristics and in vitro methane production in Brahman heifers. The first experiment assessed changes in rumen fermentation pattern and in vitro methane production post-refaunation and the second experiment investigated whether addition of nitrate to the incubation would give rise to methane mitigation additional to that contributed by defaunation. Ten Brahman heifers were progressively adapted to a diet containing 4.5% coconut oil distillate for 18 d and then all heifers were defaunated using sodium 1-(2-sulfonatooxyethoxy) dodecane (Empicol). After 15 d, the heifers were given a second dose of Empicol. Fifteen days after the second dosing, all heifers were allocated to defaunated or refaunated groups by stratified randomisation, and the experiment commenced (d 0). On d 0, an oral dose of rumen fluid collected from unrelated faunated cattle was used to inoculate 5 heifers and form a refaunated group so that the effects of re-establishment of protozoa on fermentation characteristics could be investigated. Samples of rumen fluid collected from each animal using oesophageal intubation before feeding on d 0, 7, 14, and 21 were incubated for in vitro methane production. On d 35, 2% nitrate (as NaNO3) was included in in vitro incubations to test for additivity of nitrate and absence of protozoa effects on fermentation and methane production. It was concluded that increasing protozoal numbers were associated with increased methane production in refaunated heifers 7, 14, and 21 d after refaunation. Methane production rate was significantly higher from refaunated heifers than from defaunated heifers 35 d after refaunation. Concentration and proportions of major volatile fatty acids, however, were not affected by protozoal treatments. There is scope for further reducing methane output through combining defaunation and dietary nitrate as the addition of nitrate in the defaunated heifers resulted in 86% reduction in methane production in vitro.

Coupling of full adsorption-desorption and size-exclusion chromatography (FAD-SEC) has been applied to the separation and molecular characterization of three- and four-component polymer blends. The method is based on the full adsorption of alln orn−1 components of the polymer blend in a specially designed FAD minicolumn. By appropriate eluent switching the adsorbed polymers are desorbed stepwise from the FAD minicolumn into an on-line SEC column for molecular characterization. It is shown that the desorption isotherms of particular blend components give valuable information about the appropriate displacer composition. The exact position of the desorption isotherms depends, however, both on the amount of polymer adsorbed and in the presence of other, chemically different, polymers within FAD column. The nature and composition of the displacer must, therfore, be adjusted if the intervals between the desorption of particular blend components are to be large enough to prevent displacement overlap.

Steady-state compressible isothermal lubrication problems are analyzed by the p-version finite element formulation in conjunction with the Newton-Raphson iteration procedure. Test examples confirm that this is an effective formulation for solving finite width bearing problems, and that, even for high bearing number (Λx > 1000) and coarse mesh situations, numerical solutions are accurate and converge rapidly.

This paper presents a p-version finite element formulation for incompressible lubrication analyses where the pressure field can be of any arbitrary polynomial of order p. The formulation ensures the C° continuity between mating element boundaries. Numerical examples are provided to demonstrate the simplicity of modeling and the accuracy of the formulation.

This paper presents a three node curved three dimensional beam element for linear static analysis where the element displacement approximation in the axial (ξ) and transverse directions (η and ζ) can be of arbitrary polynomial orders pξ, pη and pζ. This is accomplished by, first constructing one dimensional hierarchical approximation functions and the corresponding nodal variable operators in ξ, η and ζ directions using Lagrange interpolating polynomials and then taking the products (also called tensor product) of these hierarchical one dimensional approximation functions and the corresponding nodal variable operators. The resulting approximation functions and the corresponding nodal variables for the three dimensional beam element were hierarchical. The formulation guarantees C0 continuity. The element properties are established using the principle of virtual work. In formulating the properties of the element all six components of the stress and strain tensor are ratained. The geometry of the beam element is defined by the coordinates of the nodes located at the axis of the beam and node point vectors representing the nodal cross-sections. The results obtained from the present formulation are compared with analytical solutions (when available) and the h-models using isoparametric three dimensional solid elements. The formulation is equally effective for very slender as well as deep beams since no assumptions are made regarding such conditions during the formulation.

The effects of dietary nitrate supplementation and defaunation on methane (CH4) emission, microbial protein outflow, digesta kinetics and average daily gain were studied in lambs fed chaff containing 4.1% crude protein in dry matter. Twenty ewe lambs were randomly allocated in a 2 × 2 factorial experiment (0% or 3.1% calcium nitrate supplementation and defaunated or faunated protozoal state). Nitrate supplementation increased blood methaemoglobin concentration (P < 0.05), rumen volatile fatty acids, ammonia concentration, dry matter intake, microbial protein outflow, average daily gain, dry matter digestibility, clean wool growth and wool fibre diameter (P < 0.01). Nitrate increased CH4 production (g/day) due to greater dry matter intake, but did not affect CH4 yield (g/kg dry matter intake). Nitrate-supplemented lambs had a shorter total mean retention time of digesta in the gut (P < 0.05). Defaunation reduced CH4 production and CH4 yield by 43% and 47%, but did not cause changes in dry matter intake, microbial protein outflow, average daily gain or clean wool growth. Defaunation decreased total volatile fatty acids and the molar percentage of propionate, but increased the molar percentage of acetate (P < 0.05). Interactions were observed such that combined treatments of defaunation and nitrate supplementation increased blood methaemoglobin (P = 0.04), and decreased CH4 yield (P = 0.01).

P-Cadherin is a member of the cadherin family of cell surface glycoproteins that mediate Ca2+-dependent cell-cell adhesion and is expressed in a differential fashion in normal epithelial tissues. The expression of P-cadherin in human prostate cancer development has not been investigated previously. By immunohistochemistry, we show that P-cadherin expression is restricted to the cell-cell border of basal epithelial cells in 30 normal prostate samples. This staining is down-regulated in prostatic intraepithelial neoplasia and is absent in all 25 of the well to poorly differentiated prostate cancer specimens analyzed. To examine potential P-cadherin-regulatory elements, we sequenced the 5'-flanking region of this gene. Similar to the mouse gene, the human P-cadherin promoter is TATA-less, contains an Sp-1 binding site and, analogous to the human E-cadherin sequence, demonstrates a GC-rich region characteristic of a CpG island. Cytosine methylation of this region occurs in P-cadherin-negative prostate cancer cell lines but not in cell lines expressing this gene. In vivo, a lack of expression in 12 clinical prostate cancer specimens is not associated with methylation of the P-cadherin promoter. These results demonstrate that the expression of the basal cell marker P-cadherin is lost in prostate cancer development and that in vivo mechanisms other than cytosine methylation regulate this consistent loss of expression.

Production of the potent vasoconstrictor endothelin-1 (ET-1) by human prostate cancer cells accompanies prostate cancer progression in vivo. The predominant endothelin receptor expressed by normal prostate epithelium, ETB, is not expressed by any of the established human prostate cancer cell lines, and ETB binding is decreased on prostate cancer tissues. ETB, which may mediate ET-1 clearance and may inhibit ET-1 secretion, is encoded by a gene that contains a 5' CpG island encompassing the transcriptional regulatory region. We examined this regulatory region of the ETB receptor gene (EDNRB) to determine whether hypermethylation of cytidine nucleotides accompanies decreased ETB expression in human prostate cancer. We found somatic methylation of CpG island sequences in EDNRB in 5 of 5 human prostate cancer cell lines, 15 of 21 primary prostate cancer tissues, and 8 of 14 prostate cancer metastases (70% of samples overall). Normal tissues contained only unmethylated EDNRB. Treatment of human prostatic carcinoma cell line cultures with 5-azacytidine induced ETB mRNA expression, suggesting that CpG island methylation changes might accompany the apparent transcriptional silencing of EDNRB in vivo.

Spin polarized neutron reflectometry measurements were performed on Ni80Co20/Cu multilayers with a Cu spacer thickness of 20 A, corresponding to the second oscillation peak in the magnetoresistance of the NiCo/Cu multilayer system. Measurements in a 15 Oe field indicate a nearly perfect antiferromagnetic stacking of the magnetic moments in successive Ni80Co20 layers. The existence of a small magnetic anisotropy in these magnetically soft multilayers leads to the canting of the magnetic moments at an angle of ∼70° with respect to the neutron spin polarization. This interlayer antiferromagnetic coupling can be suppressed by an applied field of ∼200 Oe.

Fetal cells enter the maternal circulation during all human and murine pregnancy. The presence of fetal microchimeric cells has been demonstrated in lesional skin of pregnant women affected with polymorphic eruptions of pregnancy. We aimed at determining in a mouse model the role of maternal inflammation in attracting microchimeric cells. Wild type female mice were mated to transgenic males for various reporter genes or wild type male controls. We used males transgenic for the luciferase gene under the control of an ubiquitous (CMV)(C-Luc) or the VEGFR2 (V-Luc) promoter. Alternatively we used males transgenic for the EGFP under the control of the beta-actin promoter. Female pregnant mice were sensitized on day 10 of pregnancy with 2% Oxazolone. On day 16 we revealed a contact hypersensitivity reaction (CHR) by painting the right ear with oxazolone while the left ear received only the vehicle. The presence of fetal cells was then monitored using one of the following: in vivo imaging to detect luciferase expressing fetal cell real time quantitative amplification of the egfp transgene or Y chromosome in situ hybridization to detect male microchimeric cells. On femalemice bearing V-Luc fetuses, a fetal signal could be detected only on the right ear that was significantly higher when compared to controls (3362 versus 1507 photons/s/cm2, p=0.02). Wealso detected fetal cells by real time quantitative PCR in the right as well as the left ear at similar frequencies. Finally, we demonstrated the presence of fetal cells in maternal inflamed ears. Fetal cells were either among the inflammatory cells or were part of the vascular wall. We demonstrate that maternal inflamed skin can recruit fetal microchimeric cells. The fetal cells adopt an endothelial phenotype in the inflamed maternal skin. Fetal cells may therefore participate in maternal angiogenesis and inflammation.