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Differential thermal analysis (DTA) and microstructural and microprobe measurements of DTA and as-cast Ni-Re alloys with compositions between 0.20 and 0.44 mass fraction Re provide information to resolve differences in previously published Ni-Re phase diagrams. This investigation determines that the peritectic invariant between liquid, Re-rich hexagonal close packed and Ni-rich face center cubic phases, L + HCP → FCC, occurs at 1561.1 °C ± 3.4 °C (1σ) with compositions of liquid, FCC and HCP phases of 0.283 ± 0.036, 0.436 ± 0.026, and 0.828 ± 0.037 mass fraction Re, respectively. Analysis of the microsegregation in FCC alloys yields a partition coefficient for solidification, k = 1.54 ± 0.09 (mass frac./mass frac.). A small deviation from Scheil behavior due to dendrite tip kinetics is documented in as-cast samples. No evidence of an intermetallic phase is observed.

In situ measurements and ship-based resuspension experiments using annular flumes are used to determine sediment stability and critical erosion thresholds for four sites with significantly different sediment characteristics, located in the Celtic Sea at water depths of 100 m. Seasonal and spatial variability of sediment characteristics and erodability is examined, and found to be the result of changes in percentage of organic carbon in the surface sediments (R2 = 0.82) and bulk density (R2 = 0.73) respectively when individual characteristic bed parameters are considered. Principal component analysis and linear regression analysis are used to determine a predictive model for erosion threshold in the Celtic Sea (R2 = 0.99), based on grain size, sorting, kurtosis, bulk density, porosity, percentage fines, organic carbon content and chlorophyll a concentration. Physical sediment characteristics were found to be more significant controls of bed stability than biological factors. Local hydrodynamic conditions are used to determine the likelihood and frequency of resuspension given these critical erosion thresholds. Resuspension is driven by tidal currents, and is common year-round, leading to a constant re-working of bed sediments in particular at the muddier sites. This is confirmed by in situ measurements of suspended sediment concentration.

Using the principal component procedure of SAS, 10 variables; body weight (BW), body length (BL), breast girth (BG), shank length (SL), thigh length (TL), comb length (CL), comb height (CH), wing length (WL), wattle length (WAL) and wattle thickness (WT) obtained from three dual-purpose chicken breeds (Shika, Kuroiler, and Sasso), variables were separated. Similarly, stepwise discriminant analsis procedure of the SAS software was employed to evaluate variables that contribute to the overall differences in breeds. Results showed three principal components (PC1, PC2 and PC3) were extracted for all the breeds and pooled data. 45.60% of total variance was accounted for by PC1, 28.17% by PC2 and 16.22% by PC3. The principal components partitioning of total variance were 50.80, 15.10 and 9.70%, 50.82, 19.90 and 14.90%, and 48.63, 14.00 and 12.67% for Shika, Kuroiler, and Sasso breeds respectively, with different factor loadings. Communalities ranged from 0.43-0.97, 0.45-0.83, 0.45-0.88 and 0.45-0.90, indicating that a good amount of variance was accounted for. Stepwise discriminant analysis indicated that seven morphometric traits, TL, SL, WAL, WL, CL, CH and BL, contributed significantly (P

The impact of Haemoglobin, Transferrin and Carbonic Anhydrase polymorphisms on age based morphological characters was studied among Red Sokoto, Sahel and West Africa Dwarf breeds of goat. A total of 900 goats equally distributed across three age groups and both gender were used for the study. Morphometric parameters were: Body weight(BW) Horn Length (HL); Ear Length (EL); Shoulder width (SW); Neck circumference (NC); Body Length(BL); Withers Height (WH); Heart Girth (HG); Paunch Girth (PG) and Tail Length (TL) respectively. Effects of blood protein polymorphisms on morphometric measurements were observed to vary with age especially with haemoglobin and transferrin. Also carbonic anhydrase influenced body mensuration characteristics of goats aged 1-2 years in BW, HL, EL, NC, BL and TL and only TL in 2-3 years old. The FF form of carbonic anhydrase was superior for most indices. The other proteins were not definitive in their effect across age groups.Key words: Haemoglobin, Transferrin, Carbonic Anhydrase and morphometry, goat

This research evaluated the kinetics of δ-phase growth in laser powder bed additively-manufactured (AM) Inconel 625 during post-build stress-relief heat treatments. The temperatures ranged between 650°C and 1050°C, and the times from 0.25 to 168 hours. The presence of δ-phase was verified for each temperature/time combination through multiple techniques. A conventional time-temperature-transformation diagram was constructed from the time-temperature data. Comparison to the growth in wrought IN625 with a similar nominal composition revealed that δ-phase formation occurred at least two orders of magnitude faster in the AM IN625. The results of this study also revealed that the segregated microstructure in the as-built condition has a strong influence on the kinetics of δ-phase formation in AM IN625 as compared to a homogenized material. Since control of the δ-phase growth is essential for reliable prediction of the performance of IN625 components in service, avoiding heat treatments that promote the formation of δ-phase in AM components that are not homogenized is highly recommended. This will be particularly true at elevated temperatures where the microstructural stability and the consistency of mechanical properties are more likely to be affected by the presence of δ-phase.

C57BL/6 mice immunized intradermally (i.d.) with bacillus Calmette Guerin (BCG) plus killed skin-stage schistosomula are protected against subsequent infection with Schistosoma mansoni, whereas immunization by i.v. or i.m. routes is not protective. Moreover, previous immunization via the nonprotective i.v. route interfered with the ability to subsequently induce protection by i.d. vaccination, suggesting that inhibitory responses are invoked. Given the evidence that activated macrophages (M phi) play a role as effector cells in protection against schistosomiasis, we investigated the ability of spleen cells from protected and nonprotected immunized mice to produce M phi activating and deactivating cytokines. Exposure to supernatant fluids (SNs) from Ag stimulated spleen cells of i.d., but not i.v. or i.m., immunized mice activated inflammatory M phi for in vitro killing of schistosome larvae, through a mechanism dependent on both IFN gamma and TNF-alpha. No evidence was observed for the preferential induction of the M phi activating Th1 cytokines IFN-gamma and IL-2 in i.d. immunized mice, nor did spleen cells from nonprotected animals produce higher levels of the Th2 associated cytokines IL-4 and IL-10, which are known to prevent M phi activation. TGF-beta was, however, detected in SNs from unprotected mice. Moreover, the M phi inhibitory activity detected in these SNs was heat stable and neutralized by anti-TGF-beta Abs, suggesting that production of TGF-beta is at least partially responsible for the failure of i.m. and i.v. immunized mice to develop immunity to S. mansoni. Thus, the induction of down-regulatory cytokines may be an important factor limiting the efficacy of certain vaccination protocols.

Summarizes the various assessments of world conventional oil resources and unconventional (eg tar sands, heavy crude, oil shales). Outlines the three factors that fostered the still-rising oil costs: the shift to smaller fields; the move to offshore fields; and the shift to exploiting unconventional sources.