Economics of Flexible Versus Conservative Stocking Strategies to Manage Climate Variability Risk

Recommended strategies for dealing with drought include maintaining a conservative stocking rate, maintaining grazing flexibility by having yearlings as one of multiple enterprises on the ranch, and leaving a significant amount of herbaceous production at the end of the grazing season. We perform an economic analysis of these grazing strategies using a bio-economic multiperiod linear programming model with variable annual forage production and beef prices. We evaluate the economics of conservative versus flexible grazing where stock numbers are adjusted to match forage conditions. The deterministic model estimates that a flexible grazing strategy could nearly double net returns relative to a conservative strategy, but realizing this substantial economic potential means higher production costs, and it depends on a quality climate forecast that is not currently available. Maintaining grazing flexibility was determined to be very important for managing variable forage conditions, and its importance increased with the level of variability. Without annual variation in forage production, over 80% of available forage would optimally be allocated to cow–calf production. As forage variability increased to levels observed on the arid rangelands of the western United States, a 50:50 forage allocation between cow–calf and yearling enterprises was found to be optimal, but optimal cow numbers decreased over time as dry conditions force herd reductions. As compared to a cow–calf ranch only, adding flexible yearling enterprises increased average annual net ranch returns by 14% with conservative stocking and by up to 66% with flexible grazing. Herd expansion beyond a conservative level should occur with yearlings because adjusting cow numbers is too expensive relative to the potential short-term gain, even if forage conditions are known with certainty.     

Diaryloxyacetate herbicides

The discovery and investigation of a novel family of herbicides containing a diaryl acetal are described. The stability of the acetal limited herbicidal efficacy and recognizing that fact led to the design of analogs with commercial levels of post-emergence activity on broadleaf weeds. These compounds inhibited acetolactate synthase and in vitro activity data were used to guide target design. However, no members of this family provided a commercially valuable combination of herbicidal efficacy and crop selectivity.     

Immunoprophylaxis against Theileria annulata with protein from plasma membrane of infected lymphoblasts

Cross-bred (Bos taurus male x Bos indicus female) calves were protected against the homologous sporozoite-induced challenge of Theileria annulata when immunised with protein from the plasma membrane of macroschizont-infected lymphoblasts of allogeneic origin. However, such protection was parasite-strain specific with the plasma membrane originating from lymphoblasts infected and transformed by the same isolate of T. annulata sporozoites. No protection ensued when the infected lymphoblasts and sporozoites were from immunologically different isolates of T. annulata. There was enhanced proliferation of cells and evidence for lymphokine, originating from antigen-sensitised lymphocytes, demonstrable as macrophage migration inhibition factor in peripheral blood lymphocytes of the calves immunised by plasma membrane protein and challenged by sporozoites of homologous origin.     

High dietary protein combats the stress of Labeo rohita fingerlings exposed to heat shock

The amelioration effect of high dietary protein against stress was evaluated in Labeo rohita fingerlings, exposed to heat shock. Two hundred and forty fingerlings (6.57 ± 0.04 g, average weight ± SE) were randomly distributed into 4 treatment groups, each with 4 replicates was fed with either of four diets containing different levels of protein (20, 30, 40 or 45%). Water temperatures of all the treatments were within the range of 25.5–26.5°C throughout the experimental period of 30 days. After 30 days of feeding, fish were given heat shock by exposing to 38°C for 2 h. Heat shock significantly decreased (P < 0.05) liver glycogen content in treatment groups fed with 20 and 30% dietary protein, whereas unaffected in the 40 and 45% protein-fed groups. Heat shock significantly increased (P < 0.05) serum glucose and cortisol level in all the treatments. The 40 and 45% dietary protein–fed groups registered significantly higher survival (%) after the heat shock compared with their lower-protein counterparts. Heat shock increased the glycolytic, gluconeogenic, protein metabolic and antioxidative enzymes to cope up with thermal stress. Our results indicate that high-protein diet (≥40%) combats the stress due to heat shock in Labeo rohita.     

A New High-Temperature Superconductor: Bi2Sr3-x Cax Cu2O8+y

A new superconductor that displays onset behavior near 120 K has been identified as Bi(2)Sr(3-x)Ca(x)Cu(2)O(8+y), with x ranging from about 0.4 to 0.9. Single crystal x-ray diffraction data were used to determine a pseudo-tetragonal structure based on an A-centered orthorhombic subcell with a = 5.399 A, b= 5.414A, and c = 30.904 A. The structure contains copper-oxygen sheets as in La(2)CuO(4) and YBa(2)Cu(3)O(7), but the copper-oxygen chains present in YBa(2)Cu(3)O(7) do not occur in Bi(2)Sr(3-x)Ca(x)Cu(2)O(8+y). The structure is made up of alternating double copper-oxygen sheets and double bismuth-oxygen sheets. There are Ca(2+) and Sr(2+) cations between the adjacent Cu-O sheets; Sr(2+) cations are also found between the Cu-O and Bi-O sheets. Electron microscopy studies show an incommensurate superstructure along the a axis that can be approximated by an increase of a factor of 5 over the subcell dimension. This superstructure is also observed by x-ray diffraction on single crystals, but twinning can make it appear that the superstructure is along both a and b axes. Flux exclusion begins in our samples at about 116 K and is very strong by 95 K. Electrical measurements on a single crystal of Bi(2)Sr(3-x)Ca(x)Cu(2)O(8+y) show a resistivity drop at about 116 K and apparent zero resistivity at 91 K.     

Chlorophyll and nitrogen determination in coconut using a non-destructive method

Portable non-destructive meters are used to estimate foliar chlorophyll or nitrogen (N) concentrations for many crops. In this study, we calibrated chlorophyll meter (atLeaf) to estimate chlorophyll in coconut using data sets collected from wide-ranging field experiments involving plant type, cropping system, fertigation trial and soil type. The atLeaf chlorophyll meter provided good estimates for chlorophyll concentrations in coconut, with coefficients of determination greater than 0.81. The product is suitable for determining foliar chlorophyll concentration of coconut, which can serve as a generic indicator of moisture or nutrient stress. Detecting N deficiencies requires caution, because the wide range of foliage colors across genotypes does not reflect the relationship between chlorophyll index (CI) and N. Regardless, detection is good for a given genotype with different management options. The product has potential as a management tool for optimizing irrigation and fertilizer regimes in plantation crops.     

Fibre rupture phenomenon in rotor spinning

The present work relates to the occurrence of fibre rupture during fibre separation in rotor spinning and also discusses the mechanism of such rupture. The reduction in fibre length during opening has been studied at different span lengths. A correlation has been drawn showing the influence of combing roller action on yarn tenacity and elongation. Fibre rupture has direct relationship with opening roller speed. Fibre rupture and surface damage occurring due to action of opening roller together are found to mar the yarn quality index.     

The Connectivity Map: using gene-expression signatures to connect small molecules, genes, and disease

To pursue a systematic approach to the discovery of functional connections among diseases, genetic perturbation, and drug action, we have created the first installment of a reference collection of gene-expression profiles from cultured human cells treated with bioactive small molecules, together with pattern-matching software to mine these data. We demonstrate that this "Connectivity Map" resource can be used to find connections among small molecules sharing a mechanism of action, chemicals and physiological processes, and diseases and drugs. These results indicate the feasibility of the approach and suggest the value of a large-scale community Connectivity Map project.