Linkage among melanin biosynthetic mutations in Cochliobolus heterostrophus

Melanin is synthesized by C. heterostrophus from acetate via pentaketide and several dihydroxynaphthalene intermediates (Tanaka et al. 1991 Mycol. Res. 95:49-56), as it is for certain other fungi (Bell and Wheeler 1986 Ann. Rev. Phytopathol. 24:411-451; Kubo et al. 1989 Exp. Mycol 13:77-84; Chumley and Valent 1990 Mol. Plant-Microbe Int. 3:135-143). Previously, five melanin deficient mutants of C. heterostrophus were analyzed by Tanaka et al. (Mycol. Res. 95:49-56), who were unable to establish complete linkage relationships because three of the mutations (alb1, alb3, and brn1) showed no recombination when crossed to each other, and were unlinked to the other two (sal1 and pgr1), which mapped about 12 cM apart. A sixth color mutation, scr1, represented a third linkage group, but there was no evidence of its involvement in melanin biosynthesis. Independently, we have recovered six melanin-deficient mutants, one of which (alb1, Leach et al. 1982 J. Gen. Microbiol. 128:1719-1729) was included in the study of Tanaka et al. and maps to chromosome 1 on the C. heterostrophus RFLP map (Tzeng et al. 1992 Genetics 130:81-96). We report here that our remaining five melanin-deficient mutants [crm1 (light cream), crm2 (dark cream), brn1 (brown), rsy1 (rose), and probably gra3 (gray)] are linked to, but are not allelic with, alb1 (white) and constitute a gene cluster on chromosome

Prevention of Renal ApoB Retention is Protective Against Diabetic Nephropathy: Role of TGF-β Inhibition

Animal studies demonstrate that hyperlipidemia and renal lipid accumulation contribute to the pathogenesis of diabetic nephropathy (DN). We previously demonstrated that renal lipoproteins colocalize with biglycan, a renal proteoglycan. The purpose of this study was to determine whether prevention of renal lipid (apoB) accumulation attenuates DN. Biglycan-deficient and biglycan wild-type Ldlr−/− mice were made diabetic via streptozotocin and fed a high cholesterol diet. As biglycan deficiency is associated with elevated transforming growth factor-β (TGF-β), in some experiments mice were injected with either the TGF-β-neutralizing antibody, 1D11, or with 13C4, an irrelevant control antibody. Biglycan deficiency had no significant effect on renal apoB accumulation, but led to modest attenuation of DN with ∼30% reduction in albuminuria; however, biglycan deficiency caused a striking elevation in TGF-β. Use of 1D11 led to sustained suppression of TGF-β for approximately 8 weeks at a time. The 1D11 treatment caused decreased renal apoB accumulation, decreased albuminuria, decreased renal hypertrophy, and improved survival, compared with the 13C4 treatment. Thus, prevention of renal apoB accumulation is protective against development of DN. Furthermore, this study demonstrates that prevention of renal apoB accumulation is a mechanism by which TGF-β inhibition is nephroprotective

Nitrogen recycling in coastal waters of southeastern U.S. during summer 1986

Summer-time pelagic nitrogen recycling using an 15NH4+ tracer technique was studied for important biological pathways, sinks, and residence times in the microbial food web of coastal Georgia, U.S.A. Results showed that estimated rates of NH4+ regeneration by a variety of microheterotrophs and microzooplankton balanced rates of NH4+ assimilation by the microbial community, i.e., phytoplankton, bacteria and other microheterotrophs, in surface waters. In bottom water below the 1% light level, NH4+ regeneration exceeded community NH4+ assimilation by 3.5 times. However, over a period of 2 weeks, high NH4+ concentrations rarely occurred in bottom waters, and this was attributed to rapid mixing of the water column by winds and tides. Estimated mixing times from time-dependent numerical models were on the order of NH4+ turnover times of 5 to 10 hours. Overall, rates of community NH4+ assimilation exceeded rate estimates of phytoplankton N demand by 1.8 to 2.7 fold, which were made from rates of 14CO2 incorporation into proteins. In bottom samples where phytoplankton were light limited, rates of NH4+ assimilation exceeded the phytoplankton N demand by 3.6 to 11.1 fold. Calculations concerning the role of dissolved organic nitrogen in N cycling suggest that only 10% is recycled to NH4+ daily. This N could support 12 to 29% of the estimated phytoplankton N demand. Residence times of particulate nitrogen pools, based on rates of NH4+ regeneration, were on the order of 3–10 days. During summer-time hydrographic conditions and despite other losses, particulate nitrogen could recycle as often as 100 times before autumn removal processes occur off southeastern U.S

3D integrated superconducting qubits

As the field of superconducting quantum computing advances from the few-qubit stage to larger-scale processors, qubit addressability and extensibility will necessitate the use of 3D integration and packaging. While 3D integration is well-developed for commercial electronics, relatively little work has been performed to determine its compatibility with high-coherence solid-state qubits. Of particular concern, qubit coherence times can be suppressed by the requisite processing steps and close proximity of another chip. In this work, we use a flip-chip process to bond a chip with superconducting flux qubits to another chip containing structures for qubit readout and control. We demonstrate that high qubit coherence ($T_1$, $T_{2,\rm{echo}} > 20\,\mu$s) is maintained in a flip-chip geometry in the presence of galvanic, capacitive, and inductive coupling between the chips

Finely Grinding Cereal Grains in Pelleted Diets Offers Little Improvement in Nursery Pig Growth Performance

Five experiments were conducted to determine the effects of corn particle size and diet form on nursery pig performance and feed preference. In Exp. 1, 192 nursery pigs (PIC 327 × 1050; initially 14.7 lb and 26 d of age) were used in a 35-d experiment. Pens of pigs were balanced by BW and allotted to 1 of 4 treatments with 6 pigs per pen and 8 pens per treatment. The same corn and soybean meal-based diet formulation was used for all treatments. The 2 × 2 factorial consisted of the main effects of corn particle size (400 vs. 700 μm) and diet form (mash vs. pelleted). Pigs fed mash diets had improved overall ADG and greater ADFI during all periods (P \u3c 0.05) and particle size did not impact (P \u3e 0.10) performance. In Exp. 2, a study utilized 96 pigs to evaluate feed preference of pigs consuming mash diets with either 400 or 700 μm corn. Pigs overwhelmingly (P \u3c 0.05) preferred to consume 700 μm corn compared to 400 μm corn (79.3 vs. 20.7%). In Exp. 3, 224 nursery pigs (PIC 327 × 1050; initially 24.1 lb and 40 d of age) were used in a 10-d experiment to determine the effects of corn particle size in pelleted diets on nursery pig performance. Experimental treatments were formed by grinding corn to 1 of 4 different particle sizes (250, 400, 550, or 700 μm). Particle size tended to affect (P \u3c 0.10) ADG in a quadratic manner, but did not impact (P \u3e 0.10) ADFI or F/G. Pigs fed pelleted diets from either 250 or 700 μm corn had poorer ADG than the intermediate treatments. Exp. 4 utilized 91 pigs to evaluate the preference of pigs consuming pelleted diets with either 250 or 700 μm corn from Exp. 3. Even in pelleted form, pigs preferred (P \u3c 0.05) to consume diets manufactured with the coarser particle size corn (58.2 vs. 41.8%). In Exp. 5, 180 nursery pigs (PIC 327 × 1050; initially 15.8 lb and 36 d of age) were used in a 35-d experiment to determine the effects of corn particle size and pelleting on nursery pig growth performance. The 2 × 2 factorial consisted of 2 corn particle sizes (500 μm vs. 750 μm) and two diet forms (mash vs. pelleted). Overall, reducing particle size from 750 to 500 μm did not affect growth performance (P \u3e 0.10). Pelleting reduced (P \u3c 0.05) feed intake, but did not affect ADG or F/G (P \u3e 0.10). These studies suggest that there is little value to be gained by grinding corn to less than 700 microns if fed in pelleted form. Furthermore, our data suggest that, regardless if fed as mash or pellets, pigs prefer to consume diets manufactured with coarser ground corn if given the choice

Sextupole Correction of the Longitudinal Transport of Relativistic Beams in Dispersionless Translating Sections

Abstract We examine the use of sextupole magnets to correct nonlinearities in the longitudinal phase space transformation of a relativistic beam of charged particles in a dispersionless translating section, or dogleg. Through heuristic analytical arguments and examples derived from recent experimental efforts, augmented by simulations using the particle tracking codes PARMELA and ELEGANT, sextupole corrections are found to be effective in optimizing the use of such structures for beam compression or for shaping the current profile of the beam, by manipulation of the second-order longitudinal dispersion. Recent experimental evidence of the use of sextupoles to manipulate second-order horizontal and longitudinal dispersion of the beam is presented. The theoretical and experimental results indicate that these manipulations can be used to create an electron bunch with a current profile having a long ramp followed by a sharp cut-off, which is optimal for driving large amplitude wake fields in a plasma wake field accelerator

Description of TASHA: Thermal Analysis of Steady-State-Heat Transfer for the Advanced Neutron Source Reactor

This document describes the code used to perform Thermal Analysis of Steady-State-Heat-Transfer for the Advanced Neutron Source (ANS) Reactor (TASHA). More specifically, the code is designed for thermal analysis of the fuel elements. The new code reflects changes to the High Flux Isotope Reactor steady-state thermal-hydraulics code. These changes were aimed at both improving the code`s predictive ability and allowing statistical thermal-hydraulic uncertainty analysis to be performed. A significant portion of the changes were aimed at improving the correlation package in the code. This involved incorporating more recent correlations for both single-phase flow and two-phase flow thermal limits, including the addition of correlations to predict the phenomenon of flow excursion. Since the code was to be used in the design of the ANS, changes were made to allow the code to predict limiting powers for a variety of thermal limits, including critical heat flux, flow excursion, incipient boiling, oxide spallation, maximum centerline temperature, and surface temperature equal to the saturation temperature. Statistical uncertainty analysis also required several changes to the code itself as well as changes to the code input format. This report describes these changes in enough detail to allow the reader to interpret code results and also to understand where the changes were made in the code programming. This report is not intended to be a stand alone report for running the code, however, and should be used in concert with the two previous reports published on the original code. Sample input and output files are also included to help accomplish these goals. In addition, a section is included that describes requirements for a new, more modem code that the project planned to develop

Program for the evaluation of structural reinforced plastic materials at cryogenic temperatures, phase ii annual and fourth quarterly report, 29 jun. 1964 - 30 jun. 1965

Evaluation of procedures, test specimens, and test techniques for application to structural reinforced plastic materials at cryogenic temperature