Mechanism and kinetics of aging in Inconel 718

Age hardening in Inconel 718 is investigated using Brinell hardness measurements. Formation of a precipitate causes an increase in hardness

Dip-coating process: Silicon sheet growth development for the large-area silicon sheet task of the low-cost silicon solar array project

The objective of this research program is to investigate the technical and economic feasibility of producing solar-cell-quality sheet silicon by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. The past quarter demonstrated significant progress in several areas. Seeded growth of silicon-on-ceramic (SOC) with an EFG ribbon seed was demonstrated. Different types of mullite were successfully coated with silicon. A new method of deriving minority carrier diffusion length, L sub n from spectral response measurements was evaluated. ECOMOD cost projections were found to be in good agreement with the interim SAMIS method proposed by JPL. On the less positive side, there was a decrease in cell performance which we believe to be due to an unidentified source of impurities

Silicon on ceramic process. Silicon sheet growth development for the large-area silicon sheet task of the low-cost silicon solar array project

The technical and economic feasibility of producing solar-cell-quality sheet silicon was investigated. The sheets were made by coating one surface of carbonized ceramic substrates with a thin layer of large-grain polycrystalline silicon from the melt. Significant progress was made in all areas of the program

Lithium-6: A Probe of the Early Universe

I consider the synthesis of 6Li due to the decay of relic particles, such as gravitinos or moduli, after the epoch of Big Bang Nucleosynthesis. The synthesized 6Li/H ratio may be compared to 6Li/H in metal-poor stars which, in the absence of stellar depletion of 6Li, yields significantly stronger constraints on relic particle densities than the usual consideration of overproduction of 3He. Production of 6Li during such an era of non-thermal nucleosynthesis may also be regarded as a possible explanation for the relatively high 6Li/H ratios observed in metal-poor halo stars.Comment: final version, Physical Review Letters, additional figure giving limits on relic decaying particle

Evaluation of a Bioprocessed Soybean Meal on Nursery Pig Immune Status and Disease Resistance

Weaning is a stressful time in a piglet’s life that can have negative impacts on performance and health if not managed properly. The objective of this research was to evaluate the effects of a bioprocessed SBM alone or in combination with spray-dried plasma (SDP) or fishmeal (FM) on immune response at weaning with no imminent disease threat and during a porcine reproductive and respiratory virus (PRRSV) challenge. In the first trial, 239 pigs (initial BW 6.56 ± 0.87 kg, 21 d of age) were used in a 35-d study and allotted to one of 4 dietary treatments (10 pens/trt) according to initial BW and sex: positive control (CON; corn/SBM diet) containing SDP and FM, the CON with bioprocessed SBM replacing FM (BPSBM+SDP), the CON with bioprocessed SBM replacing SDP (BPSBM+FM), and the CON with bioprocessed SBM replacing SDP and FM (BPSBM). Experimental diets were fed in Phase I (d 1-7 after weaning) and II (d 8- 21) followed by a common Phase III diet (d 22-35). Assessment of immune response was based on mitogenic lymphocyte proliferation and dermal hypersensitivity and anti- IgG assay to previously sensitized antigens. Pigs fed CON were heavier (P \u3c 0.01) than pigs fed BPSBM+FM and BPSBM, and not different from pigs fed BPSBM+SDP, at the end of Phase I and II (6.99, 6.80, 6.52, or 6.60 kg, pooled SEM 0.08, respectively in Phase I or 12.47, 12.18, 11.42, and 11.85 kg, pooled SEM 0.21, in Phase II, respectively). There was no difference in lymphocyte proliferation or dermal hypersensitivity due to experimental diet. Secondary anti-OVA IgG was 2-fold lower based on optical density values in pigs fed CON compared with BPSBM+FM and BPSBM (0.78 vs. 1.56 and 1.55, pooled SEM 0.42 OD405nm, respectively). In the second trial, a total of 72 barrows (initial BW 6.68 ± 0.15 kg, 21 d of age) were used in a 21-d study (-7 to 14 d post-inoculation, DPI) with 48 PRRSV infected (POS) and 24 uninfected (SHAM) pigs. All pigs were housed individually (12 pigs/room) with POS and SHAM pigs in separate buildings and no staff transfer between buildings. POS pigs were allotted to one of the 4 diets from the first trial and SHAM pigs were allotted to either the CON or BPSBM diets. Experimental diets were fed in Phase I (-7 to 0 DPI) and II (1 to 14 DPI). On -7 DPI, SHAM pigs were vaccinated with a commercial porcine circovirus (PCV2) vaccine for determination of PCV2 neutralizing antibodies. On 0 DPI, POS pigs received a 1 x 105 tissue culture infective dose of PRRSV (NADC20) diluted in 1 mL of cell culture media. Body weight and rectal temperature were measured, and a blood sample collected on 0, 3, 7, 10, and 14 DPI. At 14 DPI, all pigs were euthanized and the lungs were removed for gross and microscopic lesion scoring. SHAM pigs had negative serum virus titers at all timepoints while POS pigs had positive serum virus titers at 3, 7, 10, and 14 DPI. POS pigs had higher rectal temperatures at 3 DPI (39.5 vs. 38.9, pooled SEM 0.09 °C, P \u3c 0.001). Dietary treatment did not impact growth performance or serum virus load at any time point. In SHAM pigs, pigs fed BPSBM had a greater proportion of pigs (P \u3c 0.05) with high levels of circulating PCV2 neutralizing antibodies compared to CON-fed pigs. The similar growth performance in pigs from both trials indicates that bioprocessed SBM can successfully replace SDP or FM and the positive impact of bioprocessed SBM on adaptive immune response indicates potential improved disease protection within commercial vaccination programs

Petrogenesis of crustal wehrlites in the Oman ophiolite: Experiments and natural rocks

In the Wadi Haymiliyah of the Oman ophiolite (Haylayn block), discordant wehrlite bodies ranging in size from tens to hundreds of meters intrude the lower crust at different levels. We combined investigations on natural wehrlites from the Wadi Haymiliyah section with an experimental study on the phase relations in a wehrlitic system in order to constrain the petrogenesis of the crustal wehrlites of the Oman ophiolite. Secondary ion mass spectrometry analyses of clinopyroxenes from different wehrlite bodies imply that the clinopyroxenes were crystallized from tholeiitic, mid-ocean ridge (MORB)–type melts. The presence of primary magmatic amphiboles in some wehrlites suggests a formation under hydrous conditions. Significantly enhanced 87Sr/86Sr isotope ratios of separates from these amphiboles imply that the source of the corresponding magmatic fluids was either seawater or subduction zone–related. The experiments revealed that under wet conditions at relatively low temperatures, a MORB magma has the potential to produce wehrlite in the ocean crust by accumulation of early olivine and clinopyroxene. These show typically high Mg# which is a consequence of the oxidizing effect of the prevailing high aH2O. First plagioclases crystallizing after clinopyroxene under wet conditions are high in An content, in contrast to the corresponding dry system. Trace element compositions of clinopyroxenes of those wehrlites from the Moho transition zone are too depleted in HREE to be in equilibrium with present-day MORB, implying a genetic relation to the V2 lavas of the Oman ophiolite, which are interpreted to be the result of fluidenhanced melting of previously depleted mantle. We present a model on the petrogenesis of the crustal wehrlites in an upper mantle wedge above an initial, shallow subduction zone at the beginning of the intraoceanic thrusting

Physician Peer Review Immunity: Time to Euthanize a Fatally Flawed Policy

This appeal involves a pretrial discovery dispute. The sole issue presented is whether the trial court erred by refusing to order the discovery of the Bard Report and other records sought by Lee Medical that relate to TriStar\u27s decision to stop outsourcing the vascular access services at its hospitals. [The court held that the consideration of whether to stop outsourcing the provision of vascular access services was not a peer review proceeding for the purpose of Tenn.Code Ann. § 63–6–219(e)] Courts construing ambiguous statutes may also consider matters beyond the text of the statute. Our conclusions regarding the scope of the privilege in Tenn.Code Ann. § 63–6–219(e) based on the statutory language, legislative history and prior amendments are buttressed by five considerations external to the statute itself. ... Fourth, the history of the use of “peer review” in the field of health care demonstrates that its focus has consistently been on physicians....Despite some internal dissent, the medical profession firmly believes that the peer review process is fundamental to improving the quality of health care

Determination of Omega_b From Big Bang Nucleosynthesis in the Presence of Regions of Antimatter

Production of regions of antimatter in the early universe is predicted in many baryogenesis models. Small scale antimatter regions would annihilate during or soon after nucleosynthesis, affecting the abundances of the light elements. In this paper we study how the acceptable range in Omega_b changes in the presence of antimatter regions, as compared to the standard big bang nucleosynthesis. It turns out that it is possible to produce at the same time both a low 4He value (Y_p < 0.240) and a low D/H value (D/H < 4e-5), but overproduction of 7Li is unavoidable at large Omega_b.Comment: 9 pages, PRD version, ref. 6 correcte

Radiative decay of a massive particle and the non-thermal process in primordial nucleosynthesis

We consider the effects on big bang nucleosynthesis (BBN) of the radiative decay of a long-lived massive particle. If high-energy photons are emitted after the BBN epoch ($t \sim 1 - 10^3$ sec), they may change the abundances of the light elements through photodissociation processes, which may result in a significant discrepancy between standard BBN and observation. Taking into account recent observational and theoretical developments in this field, we revise our previous study constraining the abundance of the radiatively-decaying particles. In particular, on the theoretical side, it was recently claimed that the non-thermal production of $^6$Li, which is caused by the photodissociation of \hefour, most severely constrains the abundance of the radiatively-decaying particle. We will see, however, it is premature to emphasize the importance of the non-thermal production of $^6$Li because (i) the theoretical computation of the $^6$Li abundance has large uncertainty due to the lack of the precise understanding of the $^6$Li production cross section, and (ii) the observational data of $^6$Li abundance has large errors.Comment: 15 pages, using REVTeX and 3 postscript figure