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Black soldier fly larvae (BSFL) are able to utilise a broad range of organic wastes to fulfil their growth needs. To acquire this basic knowledge of its digestive adaptation to various food, five organic wastes (soybean meal [SBM], wheat bran [WB], beer yeast [BY], kitchen waste [KW] and chicken manure [CM]) were fed to 3-day-old BSFL for 16 days. The growth performance, luminal pH of the gut, midgut histology, digestive enzyme activity and intestinal bacterial microbiota of the larvae were assessed. Growth performance was greatest in the KW group followed by the SBM group and was worst in the CM group. Nutrient compositions of larvae were not significantly affected by those of the food sources, with the exception of crude ash. The ultrastructural observations of midgut showed the number of mitochondria in CM and BY groups was less than other three groups. Twenty-four hours after feeding, weakly acidic, acidic, strongly acidic, and alkaline luminal pH values were detected in the anterior, middle and posterior segments of the gut in all groups, but the luminal pH values of the hindgut varied with food source. Significant lipase and esterase activity, cellulase activity, and amylase activity were detected in the intestines of larvae reared on KW, WB and BY, respectively, revealing that digestive enzyme activity was closely associated with the nutrient composition of the food source. Bacterial composition and diversity differed significantly between groups and were characterised by specific indicator bacteria, which may play important roles in food digestibility. The results suggested that different food sources induced adaptive physical, chemical and biological changes in the digestive tracts of BSFL and may indicate that BSFL developed specific strategies for nutrient utilisation and accumulation. The knowledge acquired here will be beneficial for developing rearing protocols to optimise bioconversion in this insect for their various applications.

Gradient boosting decision tree (GBDT) machine learning (ML) method was adopted for the first time to automatically recognize and conduct quantitative statistical analysis of boundaries in bainitic microstructure using electron back-scatter diffraction (EBSD) data. In spite of lack of large sets of EBSD data, we were successful in achieving the desired accuracy and accomplishing the objective of recognizing the boundaries. Compared with a low model accuracy of 40°) was ∼97 %, and block boundary was ∼96 %. The derived outcomes of ML were used to obtain insights into the ductile-to-brittle transition (DBTT) behavior. Interestingly, ML modeling approach suggested that DBTT was not determined by the density of high angle grain boundaries, but significantly influenced by the density of PAG and packet boundaries. The study underscores that ML has a great potential in detailed recognition of complex multi-hierarchical microstructure such as bainite and martensite and relates to material performance.

A multi-component lithium disilicate (LD) glass-ceramic with interlocking microstructure consisting of rod-like LD crystals and glassy matrix was ion-exchanged over wide temperature and time ranges in pure NaNO3 or mixed NaNO3 and KNO3 baths below the glass transition temperature. Treatment temperature, time and salt bath dependences of surface characteristics and mechanical properties for the ion-exchanged glass-ceramic were investigated. It was found that the glass-ceramic with limited glassy matrix could be remarkably strengthened and toughened in NaNO3 bath by adjusting the treatment temperature to a moderate level, at which Li+/Na+ exchange between the glassy matrix and the salt bath could form an ion-exchanged layer with larger depth and less stress relaxation. Furthermore, by using the mixed salt bath, the undesirable exchange of K+/Na+ in pure NaNO3 bath could be limited; further enhanced strengthening effect was achieved. The results might renew the interest on strengthening LD glass-ceramics by traditional ion-exchange process.

A lithium disilicate (LD) glass with stoichiometric composition and glass transition temperature (Tg) ∼ 470 °C was ion-exchanged over a wide temperature range below the Tg. The ion-exchange temperatures used were 380 °C or 315 °C in a pure molten NaNO3 bath, and 235 °C in a molten mixed salt bath of 50 mol% NaNO3＋50 mol% KNO3. Temperature-dependences of surface layer morphology and mechanical behavior of the ion-exchanged glass were investigated. It was found that similar surface Na+ concentrations were presented on the glass after the ion-exchange at all the three temperatures for different times. Surface failure occurred on the glass after the treatments at the two higher temperatures for longer time to increase the ion-exchanged depth. The surface failure could be completely avoid by substantially lowering the temperature to 235 °C in the mixed salt bath for much longer time to obtain a similar level of case depth. Similar strengthening effects were exhibited at the three temperatures as the ion-exchanged depth was shallower. With further increasing the depth, however, much more significantly strengthening effect could be achieved at the substantially lowered temperature. Flexural strength of the glass could be enhanced from ∼ 97 MPa to ∼ 520 MPa after the treatment at 235 °C for 128 h. The temperature-dependent effect to strengthen the LD glass by Li+/Na+ exchange was attributed to the combined effect of stress relaxation during ion-exchange and thermal contraction coefficient mismatch between the ion-exchanged surface layer and the internal bulk glass.

The carbon is one of the basic alloying solutes in steels. In the present study, the newly carbon microalloyed X80 steel was designed for the next generation of pipeline and the carbon microalloying effect of base material on the crystallographic structure of coarse grained heat affected zone (CGHAZ) of X80 girth welded joints was systematically investigated using electron back-scattering diffraction (EBSD), considering the fact that crystallography is the most intrinsic aspect in evaluating the microstructure. The results indicated a remarkable variation in the density of high angle grain boundaries and their dispersion by increasing the carbon content of 0.03wt%. It was attributed to the differential shearing mechanism, which was primarily sheared by variant pairing of V1/V2 at 0.06 wt% carbon, whereas at lower 0.03wt% carbon, V1/V4 pairing mechanism dominated the transformation. The preferential variant pairing transformation mechanism at differential carbon content therefore generated dissimilarly selected variants. Thus, as the carbon content increased, the variant selection effect upon phase transformation was attenuated by generating more variants from different Bain groups. The variant pair V1/V2 belonging to different Bain groups neighboring in CGHAZ of high carbon steel increased the density of high angle boundary (Σ3 boundary). Moreover, the variation in CTOD (crack-tip opening displacement) property of HAZ suggested that it should be primarily correlated to the block size (or density of block boundaries) of CGHAZ.

Traditional thermal tempering was applied to lithium disilicate (LD) glass-ceramic specimens with bar-like and disc-like shapes. The tempering process was conducted by heating the specimens to a temperature below the dynamic softening point, and then rapid cooling in silicone oil with different temperatures ranging from room-temperature to 300 °C to regulate the cooling rate. Effect of the oil-temperature on mechanical behavior of the tempered glass-ceramic was investigated. For the tempering at the lower oil-temperature (e.g., at room-temperature), it was found that the LD glass-ceramic specimens with both the bar-like and disc-like shapes could be remarkably strengthen and toughen, however, obvious anisotropy in fracture toughness was displayed by the specimens with the bar-like shape. With increasing the oil-temperature up to 250 °C, the mechanical anisotropy of the bar-like specimens could be significantly alleviated without much loss of the strengthening effect. The results can provide references for improving reliability of mechanical behavior for the tempered LD glass-ceramic by regulating the cooling condition according to specimen geometry.

Liquor distiller's grains with solubles (LDGS) is high in yield and rich in crude fiber and crude protein, which suggests that LDGS might be developed and used as unconventional feedstuff for ducks. The aim of this study was to investigate the effects of sources and levels of LDGS on growth performance, carcass characteristics, serum parameters, and intestinal morphology of Cherry Valley ducks from 15 to 42 D of age. A total of 3,300 15-day-old male ducks were randomly assigned into a 1 plus 2 × 5 factorial design including 2 different sources of LDGS (unfermented LDGS [ULDGS] and fermented LDGS [FLDGS]) at 5 levels (4, 8, 12, 16, and 20%) for 4 wk. Each treatment group included 6 pens with 50 ducks per pen. Levels of dietary LDGS and the interaction between sources and levels of LDGS had no effect on final body weight, average daily feed intake (ADFI), average daily gain, or feed-to-gain ratio (F:G) of ducks from day 15 to 42 (P > 0.05). Compared with dietary ULDGS, dietary FLDGS increased final body weight (P < 0.05) and ADFI (P < 0.05) and decreased the F:G (P = 0.03). The levels of LDGS and interaction effect between levels and sources of LDGS had no effect on carcass characteristics (P > 0.05). Regardless of the inclusion level, ducks fed with diets containing FLDGS had a higher percentage of thigh muscle (P < 0.01) than birds fed with diets containing ULDGS. Sources of dietary LDGS, levels of dietary LDGS, and their interaction had no effect on serum biochemistry parameters (P > 0.05) and intestinal morphology, including villus height, crypt depth, and villus height-to-crypt depth ratio (P > 0.05). In conclusion, the inclusion of LDGS in the diet at levels up to 20% had no negative effect on the growth performance, carcass characteristics, serum parameters, and intestinal morphology of ducks. Compared with ULDGS, FLDGS increased final body weight, ADFI, and thigh muscle yield and decreased the F:G of ducks. Therefore, LDGS, especially with fermentation, could be developed as an unconventional feedstuff resource for ducks from 15 to 42 D of age.

A bulk metallic glass composite (BMGC) with a composition of Ti65.6Cu13.2Pd5.6Sn3.6Nb12 was prepared via suction casting. Microstructure mainly consisting of fine β-Ti dendrites sized about 5 µm and nano-scale interdendritic glassy matrix was obtained in the BMGC. The mechanical behavior was compared with that of the same alloy in a polycrystalline state under compressive and bending conditions. It was found that the nano-scale glassy matrix with limited volume fraction remarkably increased the yield strength of the BMGC, furthermore, plastic deformability of the corresponding polycrystalline alloy could be preserve by the BMGC. Upon loading, the nano-scale glassy matrix could exert a strong restriction effect on the slip deformation inside the micron-scale dendritic crystals; no obvious shear-banding was exhibited in the glassy matrix during the deformation. This deformation characteristic might be attributed to the possible homogeneous deformation mode of the glassy matrix at the nano-scale.

This study aims at providing a new insights into the impact toughness scatter from the aspect of crystallographic structure. It demonstrated that the large impact toughness scatter associated much to the microstructure diversity. The crystallographic structure with evident scatter will display obvious discrepancy. In this work, three groups of samples simulated coarse-grained heat affected zone (CGHAZ) of an offshore engineering steel were obtained at different cooling rates. The Charpy test results showed that the toughness decreases dramatically with the decrease of cooling rate. However, the largest scatter in impact toughness occurred in the sample with medium cooling rate (15 °C/s), which was attributed to the heterogeneity in crystallographic structures. The visualization of crystallographic features showed that the prior austenite grain size has a significant effect on bainitic variant selection, which governed the effective grain size and crack propagation mechanism. CP (close-packed plane) grouping of variants is more likely to take place in large austenite grain, indicating that the size of CP region is larger than Bain zone, and the crack is short and flexural. On the contrary, in smaller austenite grain, Bain grouping of variants that always forms low angle grain boundary and favors crack propagation dominates the transformation, and it will promote the crack to propagate through the entire Bain zone and then yield large long crack. However, these two cases can co-exist in the same sample at medium cooling rate, indicating that the cleavage fracture is controlled by the effective grain size (Bain-zone size) and the scatter in impact toughness is associated much to the proportion and relative location between fine and coarse Bain zones.

Post-crystallization annealing above the Tg was applied to a lithium disilicate glass-ceramic with microstructure consisting of glassy matrix and rod-like lithium disilicate crystals, effect of the annealing on the mechanical behavior was investigated. Flexural strength and VIF toughness of the glass-ceramic unexpectedly decreased after the annealing. The mechanical behavior variation was understood based on residual micro-stress analysis. Coefficient of thermal expansion for the glassy matrix presented a tendency to increase after the annealing, which would enlarge the thermal expansion mismatch between the glassy matrix and the lithium disilicate crystals. As a result, the residual micro-stresses in the glass-ceramic abnormally increased with increasing the annealing time. The mechanical property degradation was attributed to the annealing-induced increase of the residual micro-stresses.

Ti-based bulk metallic glass composite alloys Ti 56 Zr 6 Cu 19.8 Pd 8.4 Sn 1.8 Nb 8 , Ti 64 Zr 4 Cu 13.2 Pd 5.6 Sn 1.2 Nb 12 and Ti 68 Cu 13.2 Pd 5.6 Sn 1.2 Nb 12 were designed to obtain the microstructure composing of β-Ti dendrites and glassy matrix. The compressive and three-point bending properties were investigated. It was found that the actual microstructure of the Nb-added alloys consisted of primarily precipitated β-Ti dendrites, network-like glassy matrix, and extra island-like Ti 2 Cu intermetallic phase with different volume fractions. Under compressive loading, all the Nb-added alloys presented higher yield strength combined with remarkably increased plasticity. Under bending condition, however, the alloys Ti 56 Zr 6 Cu 19.8 Pd 8.4 Sn 1.8 Nb 8 and Ti 64 Zr 4 Cu 13.2 Pd 5.6 Sn 1.2 Nb 12 with higher Ti 2 Cu volume fractions became completely brittle. The alloy Ti 68 Cu 13.2 Pd 5.6 Sn 1.2 Nb 12 could keep its plastic deformability due to the decreased Ti 2 Cu volume fraction. Compressive deforming behavior of the Nb-added alloys was determined by the ductile β-Ti phase and glassy matrix, nevertheless, bending deforming behavior of the alloys was determined by the volume fraction and distribution of the brittle intermetallics.

Chemical strengthening of a lithium disilicate (LD) parent glass with stoichiometric composition and the corresponding glass-ceramic by Li+/Na+ exchange was investigated. The ion-exchange was performed in a molten NaNO3 salt bath at 380 °C below the glass transition temperature over a wide time range from 3.75 to 480 min. It was found that strength of both the glass and glass-ceramic could be significantly enhanced after very short time treatment (3.75–15 min); however, significant strength decreases occurred similarly for the glass and glass-ceramic with further increasing the treatment time to obtain a greater ion-exchanged depth. Morphology analysis of the ion-exchanged surfaces revealed that the over-long treatment would induce surface failure for the glass, or LD crystal micro-cracking in the ion-exchanged region for the glass-ceramic. The strong time-dependence of the strengthening was attributed to dual effects of the ion-exchange. Besides the conventional “stuffing effect” of ion-exchange, the thermal expansion increase of surface layer induced by Li+/Na+ exchange might be a critical factor to be considered for strengthening the LD glass and glass-ceramic. With prolonging the processing time, the dual effects would change the surface residual stress from compressive into tensile, resulting in surface failure and undesirable strength degradation.

Objectives Purpose of the present study was to explore the improvement of wear performance for a nano fluorapatite veneering porcelain by ion-exchange. Methods Bar and disk specimens were prepared by IPS e.max Ceram as the nano fluorapatite veneering porcelain. Ion-exchange was performed in a melted KNO3 bath at two temperatures for different time-periods. After the ion-exchange, the bars were tested for flexural strength, surface Vickers hardness and HIF toughness, the disks were tested for wear performance paired with zirconia antagonist using a pin-on-disk tribometer with 10 N for 70✕104 wear cycles in artificial saliva. Wear analysis of the porcelain and zirconia was performed with a 3D profilometer. The microstructure and worn surface morphology were examined with scanning electron microscopy. One-way analysis of variance and Tukey's post-hoc pairwise comparison were used to analyse the wear data. Results The nano fluorapatite veneering porcelain before ion-exchange presented strong time-dependent wear behavior. Furthermore, wear rate of the original porcelain exhibited a very large standard deviation in the running-in wear stage, which was correlated with highly inhomogeneous distribution of the characteristic fluorapatite crystals in the microstructure. After ion-exchange at 350 °C and 380 °C, especially after the processing at 350 °C for 128 h, the wear rates of both running-in and steady wear stages could be significantly decreased. More importantly, the standard deviation of wear rate in the running-in wear stage could be remarkably reduced after the treatment. The improved reliability of wear performance was attributed to the strengthening and toughening effects of the ion-exchange processing. Conclusion For the fluorapatite veneering porcelain, the ion-exchange protocol to obtain an ion-exchange layer with less stress relaxation and a considerable depth could strengthen and toughen the porcelain; as a result, the reliability of wear performance could be remarkably improved.

Mass sensitive piezoelectric biosensors based on micro-electro-mechanical system (MEMS) fabrication techniques were developed for biomaterial detection. In this work, both 4-inch double-sided polished silicon wafer was used as support layers. The SiO 2 /Si 3 N 4 layers were firstly grown on both sides of the wafer to serve as the etching mask and the potassium hydroxide solution (KOH) wet etching stop layer. The diaphragm chambers were then wet etched in KOH solution until the remaining thickness of silicon was about 50 μm. The residual thin silicon layer could reduce the stress and maintain a good mechanical strength for the following fabrication processes. After that, the bottom electrode/piezoelectric layer/polyimide layer/top electrode was fabricated and patterned on the other side of the wafer successively. Then the residual thin silicon layer in the chambers was etched away and a Au layer with 50 nm thickness was sputtered on the bottom of the chambers as the immobilization surface for biomaterial specific adsorption. The square sensors with different length of sides were designed to investigate the size effect on the resonance performance. The resonant frequency shifts could be measured and the corresponding mass of the attached biomaterial could be calculated. The piezoelectric diaphragms sensors have a potential application for biomaterial detection.

Lead-free ferroelectric 0.82K 0.5 Na 0.5 NbO 3 −0.18AgNbO 3 (KNN−AN) films were successfully synthesized by a chemical solution deposition (CSD) method. In particular, silver acetate was dissolved in 2-methoxyethanol with the aid of nitric acid and molecular sieve was used to remove residual moisture in the precursor solution at room temperature. The effects of the thickness on the structures and electrical properties of the KNN–AN films were systematically investigated. The KNN–AN film with the thickness of 2.53 µm showed good dielectric properties and well saturated polarization-electric field hysteresis loops.

Piezoelectric polymers have been for the fabrication of acoustic wave biosensors due to their light weight, low cost, and ease to form different shapes. This paper presents the design and resonance behavior of polyvinylidene fluoride (PVDF) diaphragms for biosensor applications. The phase spectra of the diaphragms were measured to determine the resonance behavior. The influence of boundary condition, excitation voltage and film thickness on the resonance behavior are discussed. After immobilizing the biological probe on gold surface, the diaphragms can be used for detecting target bio-molecules.

The Swimming crab Portunus trituberculatus (Portunidae) is an important economically food species. To provide molecular markers for P. trituberculatus, we isolated and characterized polymorphic microsatellite markers. We developed a 5'-anchored genomic library of P. trituberculatus DNA, and derived 45 positive clones. We designed 30 pairs of primers from the sequences of these clones, and 10 of which were polymorphic. The loci were screened in 31 P. trituberculatus individuals; the number of alleles ranged from 2 to 5. The observed heterozygosity ranged from 0.20 to 0.49 and the expected heterozygosity ranged from 0.50 to 0.78. The polymorphism information content per locus ranged from 0.37 to 0.75. These polymorphic microsatellite markers may provide some useful information for the population genetic studies of swimming crab and other Portunus species.

The generation of insulin-producing pancreatic β-cells from stem cells in vitro would provide an unprecedented cell source for drug discovery and cell transplantation therapy in diabetes research. The fractionation, expansion and conversion of primary duck pancreas-derived mesenchymal stem cells (PSCs) into functional β-cells are described in this study. The cell surface antigens of PSCs, FOXA2, SOX9, NKX6.1 and INS were detected by immunofluorescent stain and flow cytometry for determining the biological characteristics of PSCs. The genes CD44, Ki67, Vimentin, C-myc, glucagon, PDX1 and insulin were detected by reverse-transcription polymerase chain reaction techniques. The growth curves of different passages were all typically sigmoidal. Karyotype analysis was conducted to estimate the stability of PSCs. A simple protocol was developed to assess functional differentiation by assessing the expression of pancreas β-cell markers, the staining of dithizone and confirmation of insulin secretion. Insulin and PDX1 were all increased in differentiated cells compared to controls. Differentiated cells secreted insulin in a glucose-responsive manner.

By enquiring what happens to the remaining mode when one makes one-mode n-photon counting for the two-mode squeezed state, we show that the two-mode squeezed state will collapse to a counting operator in the remaining mode with a new smaller quantum efficiency of the detector. We also derive its P-representation.

In this study, we use the nested meshes to approximate the space fractional differential equations. Two approaches are used to approximate the second order derivative. It is obvious that the nested meshes method is more effective in solving large scale problems. Matrix building and how to introduce the boundary condition are both presented. Two examples are given to show the effects of the number of subdivisions in each nested interval on the accuracy in different cases of various domain scales.

The acoustic emission extraction experiment of rotor crack fault has done on the rotor comprehensive fault simulation test-bed. Characteristics of acoustic emission signal of different crack rotors in various depth and conditions are analyzed. The noise-disturbing problems and the noise-eliminating methods of the acoustic emission signal were researched in the paper, and the comparison has been done with the vibration method of crack fault diagnosis by the experiment. The advantages of acoustic emission technique has been highlighted in the early period crack fault diagnosis. The wavelet packet technique was applied to obtain the characteristics of acoustic emission signal of the rotor crack propagation. the diagnosis results are shown to be quite clear, reliable and accurate.

Diamond-like carbon (DLC) nanodot arrays were prepared by filtered cathodic arc plasma (FCAP) technique at room temperature with the aid of anodic aluminum oxide (AAO) template at a bias of −50 V. The average diameter of highly ordered and vertical DLC nanodots was ∼90 nm, and the nanodot density was estimated to be ∼10 10 cm −2 . A broad asymmetric band attributed to characteristic band of DLC ranging from 1000 to 2000 cm −1 was detected by Raman spectrum. A sp 3 /(sp 3 +sp 2 ) ratio of 68.2% was measured by X-ray photoelectron spectrum (XPS). A low threshold field of 4 V/μm at 10 mA/cm 2 and a high current density of 43.2 mA/cm 2 at 5 V/μm were achieved. And based on Fowler–Nordheim plot, the value of work function for the DLC nanodot arrays was estimated in the range 0.4–1.84 from a linear plot. The results show that the DLC nanodot arrays can be a promising candidate as a field emission emitter.

An ear marginal fibroblast cell bank was established from the Jining Black Grey (JBG) goat using attachment culture and freezing biotechniques. This bank included 32 ear samples (15 males and 17 females) and has stocks of 168 cryogenically preserved vials, each vial contained 4.0 × 10 6 cells per milliliter. The cells of the bank that were checked for the quality and the biological characteristics showed a typical fibroblast morphology when they cultured in vitro. The growth curve consisted of a growth curve consisting of a latent phase, logarithmic growth phase and stationary phase, cell population doubling time (PDT) of 48 h. The chromosome analysis showed that the frequency of cells having the diploid number of chromosomes (60) was 98.65 ± 2.89%, and no microbe contamination (bacteria, epiphyte, virus or mycoplasma) was detected. In addition, lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) zymography indicated that this cell bank was free of cross-contamination. At 24, 48 and 72 h after transfection, the expression efficiency of pEGFP-C1, pEGFP-N3, pEYFP-N1, pECFP-N1, pECFP-mito and pDsRed1-N1 were between 11.8% and 56.3%. The fluorescence could be observed well-distributed in cytoplasm and nucleus except for some cryptomere vesicles at 24 h after transfection. These newly established cell lines meet all the quality control standards established by the American Type Culture Collection. We have employed a new method for conserving the genetic resources of an important and endangered animal breed. The fibroblast bank that we have established from the JBG goat also provides an invaluable material resource for future studies that will utilize molecular and cell biology applications.

In this paper, we present a new approach to the fabrication of integrated silicon-based piezoelectric diaphragm-type biosensors by using sodium potassium niobate-silver niobate (0.82KNN-0.18AN) composite lead-free thin film as the piezoelectric layer. The piezoelectric diaphragms were designed and fabricated by micro-machining technology and chemical solution deposition. The fabricated device was very sensitive to the mass changes caused by various targets attached on the surface of diaphragm. The measured mass sensitivity value was about 931 Hz/μg. Its good performance shows that the piezoelectric diaphragm biosensor can be used as a cost-effective platform for nucleic acid testing.

The presence of latent bacteria is a serious problem in plant tissue cultures. While endophytes are generally beneficial to plants in situ, they may affect culture growth under the modified conditions in vitro. The present study was undertaken to identify and characterize endophytic bacteria associated with the medicinal plant Echinacea in tissue culture. Based on classical microbiological tests and 16S rRNA analyses, it was found that endophytic bacteria associated with aseptically micropropagated Echinacea plantlets are representatives of several genera, Acinetobacter, Bacillus, Pseudomonas, Wautersia (Ralstonia) and Stenotrophomonas. Based on TLC and HPLC analyses, we found that Pseudomonas stutzeri P3 strain produces plant hormone, auxin (indole-3-acetic acid, IAA). Antibiotic resistance was also assessed as a virulence factor. The majority of endophytic bacteria were resistant to the antibiotic kanamycin, but susceptible to chloramphenicol. Recommendations for propagating Echinaceain vitro cultures involve the addition of chloramphenicol, tetracycline, and ampicillin, antibiotics that cause no side effects on these plant species.

Background Heme oxygenase-1 (HO-1), a cytoprotective protein, may be important in ameliorating hepatic ischemia-reperfusion (I/R) injury, a critical factor in the dysfunction of the aged liver after transplantation. Methods We used hemin to overexpress HO-1 and analyze its effects in a model of I/R in aged livers used for orthotopic transplantation. Results The SGOT levels in the hemin group were significantly lower than those of the saline treatment group. Hemin liver grafts showed markedly fewer apoptotic (TUNEL+) liver cells after reperfusion compared with the controls. The plasma nitric oxide levels in the hemin group were significantly lower than those in the control group. Unlike untreated or hemin + Znpp–treated orthotopic liver transplant controls, iNOS expression in the hemin group was almost absent at 12 and 24 hours, after reperfusion. In contrast, eNOS was comparable in hemin and saline orthotopic liver transplants. The increased levels of Bcl-2 expression compared with saline controls were most pronounced at 12 hours after transplantation. In contrast, caspase 3 was lower at 24 hours among the hemin-pretreated group compared with saline-treated liver transplant controls. Conclusions HO-1 alleviated the I/R injury in the aged liver by suppressing local expression of inducible nitric oxide synthase and by modulating pro- and antiapoptotic pathways.

After an intensive phase of prospecting using vibracores, the inner-middle shelf west-north-west of the wave-dominated Orange Delta off southern Namibia is currently being mined for marine diamonds. The diamonds were deposited by surf-zone processes in gravels during Pleistocene low sea-level stands down to depths of about 130 m. As sea level rose to its present level during the postglacial transgression, between about 18 000 and 6 000 yr BP, water depth steadily increased in the study area and drowned the gravels. Initially, quartzose fine to very fine sand of the delta-front environment was deposited on top of the gravels. Finally, prodeltaic silts and clays of the seaward prograding-feather edge of the Holocene Orange Delta were deposited on the delta-front sands. However, the actively burrowing infauna of the region was able to bioturbate the prodeltaic silt and clay into the delta-front sand. As a result, representative vibracores reveal a typical fining-upward transgressive sequence with the upper 30 cm mainly consisting of muddy sand or sandy mud. Grain-size analysis of vibracored and grab-sampled unmined surface sediment and mined surface sediment has shown that unimodal size-distributions characterise the sand-fractions of unmined surface sediment and that polymodal size-distributions characterise those of the mined surface sediment. Conservation corridors are proposed both to preserve the original transgressive sequence and to provide refuges for the benthos to recolonise the substrate after mining.

Carbon nanotubes have been widely studied due to its excellent electrical, thermal and mechanical properties, showing promising applications in both active and passive components in electronic devices. However, for such devices to be developed, compatibility issues for obtaining quality carbon nanotubes with suitable underlying substrates have to be understood. In this work, a technique to study the impact of each under layer on carbon nanotubes would be discussed. Vertically aligned multiwalled carbon nanotubes are grown on patterned metal trace with suitable barrier layers. In situ electrical measurement of the nanotubes using manipulators in a field emission scanning electron microscope was performed to understand the electrical transport at each interface.

Composite cements where large amounts of blast furnace slag (BFS) replace Portland cement are currently used for immobilisation of ILW. Hydration of BFS is activated by the small amount of OPC present but the amount of reaction that occurs is limited at ambient temperatures. Increasing the temperature increases the hydration of the BFS but large amounts still remain unreacted, leaving a porous matrix where the capillary pores remain filled with a highly alkaline solution. This solution causes corrosion of reactive metals giving rise to expansive reactions and hydrogen release, and it can destroy the structure of zeolites releasing the adsorbed species.Apart from OPC, BFS hydration can be activated by other compounds such as hydroxides, sulphates, silicates, and calcium aluminate cements. The use of these alternatives gives rise to binders such as ettringite and strätlingite which have a different chemistry where the pore solution has a lower pH. Corrosion of metals does not readily occur in these binders. This may be due to the reduced pH but could also arise from the lack of pore water, as these binders bind more water in their structure so that it is not available for transport of ionic species. This extra water binding also has potential for immobilisation of sludges where high w/s ratios are necessitated by the need to transport the sludge.This paper will review some of the alternative activators for slag hydration and present experimental results on several systems where slag has been activated with compounds other than OPC.