Intermediate Wheatgrass Seed Production Responses to Fertilizers and Cultural Practices

Intermediate wheatgrass Agropyron intermedium (Host) Beauv. is a cool season, sod farming rhizomatous and/or stoloiferous grass, best adapted to upland silt or silty clay loam soils. Intermediate wheatgrass has a fast rat9 of root spread by rhizomes and sometimes stolon’s with late summer (July 15 August 30) seed maturity. The major area of distribution of intermediate wheatgrass in the United States is central North Dakota, South Dakota, Nebraska, Idaho and Washington, with a minor distribution area east to Minnesota and west to Colorado, Montana, and Wyoming. A growing interest in reseeding the Great Plains, both to improve the rangeland and to convert some cropland to grassland, has increased the demand for grass seed. Intermediate wheatgrass has increased the livestock carrying capacity of the western rangeland in the areas where it is grown with a highly digestible, palatable feed. Skills required to produce high yields of grass seed are much the same as those needed to produce high yields of other farm crops. Seed production fields need to be carefully selected. Cultivation, fertilization, and harvesting must be timely and intelligently carried out. Special skills are necessary in selecting a proper seedbed, planting date and rate, planting machinery, and land free of quack grass. The objectives of this research were to determine the effect· of certain cultural practices and nitrogen fertilizer treatments on the seed yield of intermediate wheatgrass in South Dakota. The experimental hypothesis set up for this experiment was that added nitrogen and selected cultural practices have no significant effect on the seed yield of intermediate wheatgrass

Full activation of the rat oocyte by protein synthesis inhibition requires protein phosphatase activity

The rat oocyte provides an interesting system in which to dissect the control mechanisms involved in the transition between a meiotic M phase and a mitotic interphase. In this study, we show that in rat oocytes activated parthenogenetically by puromycin, okadaic acid (a potent inhibitor of protein phosphatases 1 and 2A) induced an increase in histone H1 kinase activity suggesting that MPF was reactivated. However, the inhibition of phosphatases 1 and 2A shortly after second polar body extrusion did not allow the formation of a metaphase-like spindle, although microtubule polymerization was not inhibited. Instead, the chromatin remained condensed as a single mass and a large aster formed around it

Land management and mobilization in Europe: regimes, policies and processes: a comparison framework applied to Gland, Switzerland

Peer Reviewe

Refined functional relations for the elliptic SOS model

In this work we refine the method of [1] and obtain a novel kind of functional equation determining the partition function of the elliptic SOS model with domain wall boundaries. This functional relation is originated from the dynamical Yang-Baxter algebra and its solution is given in terms of multiple contour integrals.Comment: v2: details of derivations and reference added, typos fixed, accepted for publication in NP

Aspects of the physiology and diseases of the North American elk

Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some elk herds in Oregon. A newly developed drug, Etorphine, together with its antagonistic companion, Dip renorphine, was used to immobilize elk. Substantial differences were found in the amounts required and animal responses dependent upon age, physical condition and life history. Whole blood samples were obtained from 60 living elk for hematological studies. The parameters examined included hemoglobin levels, packed cell volume, erythrocyte and leukocyte counts, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, and the percentage distribution of neutrophils, band cells, lymphocytes, monocytes, eosinophils, and basophils. Respiration rate, heart rate, and body temperature were measured for nine drugged elk. Sickling of erythrocytes was found in the blood of two female elk. Serum was separated from the blood of 72 living elk and 22 recently shot elk of mixed ages and sexes. Serum proteins were differentiated by electrophoretic analysis. Values obtained for total protein, albumin, total globulin, albumin/globulin ratio, and for the alpha1, alpha2, beta and gamma globulins, were grouped and summarized to facilitate comparisons based on age and sex, as well as between living and dead, and captive and free-living elk. Total serum protein concentrations were markedly higher in the older age groups of both captive and freeliving elk. An apparent tendency to higher albumin levels was found among males of this species. Values for serum concentrations of sodium, potassium, calcium, inorganic phosphorus, blood urea nitrogen, Chlorides, Cholesterol, glucose, direct bilirubin, total bilirubin, creatinine, and uric acid, as well as activity levels of alkaline phosphatase, lactic dehydrogenase, and serum glutamic oxalacetic transaminase were obtained. Sodium/ potassium and calCium/phosphorus ratios were calculated. Urine speciments were obtained from seven elk and analyzed for the presence of glucose. Young elk, both captive and free-living, had higher serum values for sodium, calcium, inorganic phosphorus, glucose and alkaline phosphatase than did the older age group. Mature elk, both captive and free-living, had higher serum values for calcium/phosphorus ratio, blood urea nitrogen, creatinine, uric acid and serum glutamic oxalacetic transaminase than did those under two years of age. Differences in serum Chemistry were also found between captive and free-living elk. Serological tests on sera from 67 elk tested were negative for brucellosis and bluetongue virus. Tests for leptospirosis on sera from 29 elk by the macroscopic agglutination method were all negative. Of 38 free-living elk tested for leptospirosis by the microscopic agglutination test, 16 showed positive reactions to one or more serotypes at a significant titer of 1:100 or greater. Another eight showed positive reactions at the 1:50 level. This is believed to the first report of serological reactivity to leptospirosis reported for elk. Internal organs from 39 elk were examined for the presence of adult helminths, and fecal pellets from 82 elk were examined for the presence of parasite eggs. Lethal numbers of Dictyocaulus viviparus were recovered from the respiratory organs of two yearling male elk. Two nematodes of the Trichostrongylus axei and Ostertagia circumcincta, were found that have not been previously reported from Roosevelt elk. Fascioloides magna and Oesophagostomum venulosum were also found. The common winter tick, Dermacentor albipictus and Ixodes pacificus were collected from Roosevelt elk. This latter species has not been previously reported in elk. Increased gannna globulin values and concomitant decreases in albumin were observed in tick-infested elk

Functional characterization of reappearing B cells after anti-CD20 treatment of CNS autoimmune disease.

The anti-CD20 antibody ocrelizumab, approved for treatment of multiple sclerosis, leads to rapid elimination of B cells from the blood. The extent of B cell depletion and kinetics of their recovery in different immune compartments is largely unknown. Here, we studied how anti-CD20 treatment influences B cells in bone marrow, blood, lymph nodes, and spleen in models of experimental autoimmune encephalomyelitis (EAE). Anti-CD20 reduced mature B cells in all compartments examined, although a subpopulation of antigen-experienced B cells persisted in splenic follicles. Upon treatment cessation, CD20+ B cells simultaneously repopulated in bone marrow and spleen before their reappearance in blood. In EAE induced by native myelin oligodendrocyte glycoprotein (MOG), a model in which B cells are activated, B cell recovery was characterized by expansion of mature, differentiated cells containing a high frequency of myelin-reactive B cells with restricted B cell receptor gene diversity. Those B cells served as efficient antigen-presenting cells (APCs) for activation of myelin-specific T cells. In MOG peptide-induced EAE, a purely T cell-mediated model that does not require B cells, in contrast, reconstituting B cells exhibited a naive phenotype without efficient APC capacity. Our results demonstrate that distinct subpopulations of B cells differ in their sensitivity to anti-CD20 treatment and suggest that differentiated B cells persisting in secondary lymphoid organs contribute to the recovering B cell pool

Cellular Viral Rebound after Cessation of Potent Antiretroviral Therapy Predicted by Levels of Multiply Spliced HIV-1 RNA Encoding nef

To characterize newly arising replication of human immunodeficiency virus (HIV) type 1 in vivo at the cellular level, distinct viral RNA species in peripheral blood mononuclear cells (PBMCs) from HIV-1-infected patients were monitored during 2 weeks of structured treatment interruption (STI). HIV-1 RNA encoding tat/rev and PBMC-associated virions were almost completely depleted during antiretroviral therapy and emerged simultaneously after 2 weeks of STI, thus specifically reflecting productive viral infection at the cellular level. The magnitude of these correlates of reappearing cellular viral replication was predicted by during-therapy levels of nef transcripts in PBMCs. Significant rebound of plasma viremia, representing the progeny of a broader range of anatomical compartments, preceded and predicted productive infection in PBMCs. Thus, cellular viral rebound in PBMCs likely was primed before STI by the expression of nef in HIV-1-infected PBMCs that lacked virion production and was subsequently triggered by the plasma viremia that preceded the recurrence of productively infected PBMC

Interaction Of Electrons With Spin Waves In The Bulk And In Multilayers

The exchange interaction between electrons and magnetic spins is considerably enhanced near interfaces, in magnetic multilayers. As a result, a dc current can be used to generate spin oscillations. We review theory and experimental evidence. The s-d exchange interaction causes a rapid precession of itinerant conduction-electron spins s around the localized spins S of magnetic electrons. Because of the precession, the time-averaged interaction torque between s and S vanishes. An interface between a magnetic layer and a spacer causes a local coherence between the precession phases of differnt electrons, within 10 nm from the interface, and restores the torque. Also, a second magnetic layer with pinned S is used to prepare s in a specific direction. the current-induced drive torque of s on S in the active layer may be calculated from the spin current (Slonczewski) or from the spin imbalance Delta-mu (Berger). Spin current and Delta-mu are proportional to each other, and can arise from Fermi-surface translation, as well as from expansion/contraction.Comment: Invited paper at Seattle MMM01 Conference, Nov. 2001 (to appear in J. Appl. Phys.

Rural agroindustry in Latin America : an evaluation of the PRODAR Network

Abstracts in French and Spanis