The productivity of organic dairy herds

This report was presented at the UK Organic Research 2002 Conference. Organically managed ruminant systems place particular emphasis on maximising production from forage. Therefore, it is important that efficiency measures take full account of forage inputs. The Livestock Production Efficiency Calculator (LPEC) calculates the total metabolisable energy (ME) required by livestock and estimates forage inputs as the difference between total requirement and that supplied by other measured feeds. Productivity is expressed in terms of output (£) minus other valued inputs (£) per unit of forage ME. Estimates of production parameters were used to produce productivity indices for thirteen organic dairy herds. The productivity of herds was compared, and sensitivity analyses were conducted to examine the potential impact of a number of economic and production scenario. The relationships between yield, fertility, culling and herd productivity were examined. The advantages of this productivity analysis of organic production systems is that full account is taken of the most important input i.e. grazed and conserved forage and that all of the determinants of productivity and their interactions are considered

Fertility and fertility management in thirteen well-established organic dairy herds in the UK

This report was presented at the UK Organic Research 2002 Conference of the Colloquium of Organic Researchers (COR). Milk production and breeding records from thirteen organic dairy herds were collected between January 1997 and December 1999. Mean lactation yields in the herds ranged from 5127 kg to 7031 kg. Whilst seasonality of calving varied widely between herds, a majority of them (6/13) were autumn calving. Mean calving to first service interval was 80 days (range 68 to 97), and mean calving interval was 385 days (range 370 to 413). The mean number of services per conception was 2.3 (range 1.6 to 3.1). Overall culling rates and culling rates for fertility related problems were at 15.8% and 5.4%, respectively. A preliminary study of selected breeding periods of cows that had a subsequent calving revealed no significant differences in calving interval between high or low yielding cows or between cows with different calving month or parit

DNA sequence of the mouse H-2Dd transplantation antigen gene

The inbred BALB/c mouse has three transplantation antigens, H2-Kd, H2-Ld, and H2-Dd. We present the complete nucleotide sequence of the H2-Dd gene as well as 777 residues of previously unpublished H-2Dd protein sequence. These data complete the sequences of all the BALB/c transplantation antigen genes and permit detailed comparison with each other and with their counterparts from the inbred C57BL/10 mouse. Transplantation antigens may differ from one another by as much as 5%-15% of their amino acid sequence for the external domains. These extensive differences may arise by gene conversion. The H-2D region of the BALB/c mouse encodes the H2-Dd and the H2-Ld genes. Serologic data suggest that at least two additional transplantation antigen molecules, H2-Rd and H2-Md, are encoded in the H-2D region of the major compatibility complex. Paradoxically, gene cloning studies have only identified the H2-Dd and the H2-Ld genes in the H-2D region. A complete DNA sequence of the H2-Dd gene shows that a variety of alternative splice sites exist throughout the gene, which may lead to additional gene products and may explain the multiplicity of H-2D-encoded polypeptides

AN EXPERIMENTAL STUDY OF USER SATISFACTION WITH MULTIPLE DIALOG MODES

This paper investigated a normative theory that says computer users have different dialog needs depending on their level of experience in using a computer. It hypothesizes that the answer to satisfy the needs of a mixed population is to have multiple dialog modes that the user is free to choose from and switch between as required. The hypotheses that experts and novices would be more satisfied with multiple dialog modes than with just one mode were tested empirically in a controlled laboratory setting. Both novice and expert computer users used one of three types of user-system interfaces (menu, command language, or both modes) to solve the same database problem. Results showed that those with both types of dialog modes were more satisfied and performed better than the command language group. However, they were statistically equal to the menu group, while the menu group\u27s satisfaction rating and performance scores were slightly better. It was concluded that the subject\u27s choice of dialog mode, when both modes were available, and their satisfaction with a dialog mode have more to do with past experience and preference than with the difference in expert and novice problem solving strategies

Preliminary measurements of the edge magnetic field pitch from 2-D Doppler backscattering in MAST and NSTX-U

The Synthetic Aperture Microwave Imaging (SAMI) system is a novel diagnostic consisting of an array of 8 independently-phased antennas. At any one time, SAMI operates at one of 16 frequencies in the range 10-34.5GHz. The imaging beam is steered in software post-shot to create a picture of the entire emission surface. In SAMI’s active probing mode of operation, the plasma edge is illuminated with a monochromatic source and SAMI reconstructs an image of the Doppler back-scattered (DBS) signal. By assuming that density fluctuations are extended along magnetic field lines, and knowing that the strongest back-scattered signals are directed perpendicular to the density fluctuations, SAMI’s 2-D DBS imaging capability can be used to measure the pitch of the edge magnetic field. In this paper we present preliminary pitch angle measurements obtained by SAMI on the Mega-Amp Spherical Tokamak (MAST) at Culham Centre for Fusion Energy and on the National Spherical Torus Experiment Upgrade at Princeton Plasma Physics Laboratory. The results demonstrate encouraging agreement between SAMI and other independent measurements

Recommendations for Practitioners Engaged in Antitrafficking Task Forces: An Evalaution of the Enhanced Collaborative Model Task Forces to Combat Human Trafficking

The Enhanced Collaborative Model (ECM) Task Force to Combat Human Trafficking Program funded task forces comprised of law enforcement officials, prosecutors, victim service providers, and other stakeholders at the local, state, and federal levels. This brief details recommendations from the Urban Institute's 10-site evaluation of ECM task forces across the United States. Recommendations were derived from the findings of our analysis and directly from task force stakeholders' responses to interview questions about task force recommendations and best practices. Respondents summarized recommendations across four categories including structure, operation, and funding of ECM task forces; collaboration among stakeholders; survivor engagement and service provision; and task force training, focus, and activities

Diel- and temperature-driven variation of leaf dark respiration rates and metabolite levels in rice

Leaf respiration in the dark (R-dark) is often measured at a single time during the day, with hot-acclimation lowering R-dark at a common measuring temperature. However, it is unclear whether the diel cycle influences the extent of thermal acclimation of R-dark, or how temperature and time of day interact to influence respiratory metabolites. To examine these issues, we grew rice under 25 degrees C : 20 degrees C, 30 degrees C : 25 degrees C and 40 degrees C : 35 degrees C day : night cycles, measuring R-dark and changes in metabolites at five time points spanning a single 24-h period. R-dark differed among the treatments and with time of day. However, there was no significant interaction between time and growth temperature, indicating that the diel cycle does not alter thermal acclimation of R-dark. Amino acids were highly responsive to the diel cycle and growth temperature, and many were negatively correlated with carbohydrates and with organic acids of the tricarboxylic acid (TCA) cycle. Organic TCA intermediates were significantly altered by the diel cycle irrespective of growth temperature, which we attributed to light-dependent regulatory control of TCA enzyme activities. Collectively, our study shows that environmental disruption of the balance between respiratory substrate supply and demand is corrected for by shifts in TCA-dependent metabolites.Peer reviewe

CAPRI and RASAL impose different modes of information processing on Ras due to contrasting temporal filtering of Ca(2+)

The versatility of Ca(2+) as a second messenger lies in the complex manner in which Ca(2+) signals are generated. How information contained within the Ca(2+) code is interpreted underlies cell function. Recently, we identified CAPRI and RASAL as related Ca(2+)-triggered Ras GTPase-activating proteins. RASAL tracks agonist-stimulated Ca(2+) oscillations by repetitively associating with the plasma membrane, yet CAPRI displays a long-lasting Ca(2+)-triggered translocation that is refractory to cytosolic Ca(2+) oscillations. CAPRI behavior is Ca(2+)- and C2 domain–dependent but sustained recruitment is predominantly Ca(2+) independent, necessitating integration of Ca(2+) by the C2 domains with agonist-evoked plasma membrane interaction sites for the pleckstrin homology domain. Using an assay to monitor Ras activity in real time, we correlate the spatial and temporal translocation of CAPRI with the deactivation of H-Ras. CAPRI seems to low-pass filter the Ca(2+) signal, converting different intensities of stimulation into different durations of Ras activity in contrast to the preservation of Ca(2+) frequency information by RASAL, suggesting sophisticated modes of Ca(2+)-regulated Ras deactivation

Stage-specific sensitivity to p53 restoration during lung cancer progression

2011 May 25Tumorigenesis is a multistep process that results from the sequential accumulation of mutations in key oncogene and tumour suppressor pathways. Personalized cancer therapy that is based on targeting these underlying genetic abnormalities presupposes that sustained inactivation of tumour suppressors and activation of oncogenes is essential in advanced cancers. Mutations in the p53 tumour-suppressor pathway are common in human cancer and significant efforts towards pharmaceutical reactivation of defective p53 pathways are underway1, 2, 3. Here we show that restoration of p53 in established murine lung tumours leads to significant but incomplete tumour cell loss specifically in malignant adenocarcinomas, but not in adenomas. We define amplification of MAPK signalling as a critical determinant of malignant progression and also a stimulator of Arf tumour-suppressor expression. The response to p53 restoration in this context is critically dependent on the expression of Arf. We propose that p53 not only limits malignant progression by suppressing the acquisition of alterations that lead to tumour progression, but also, in the context of p53 restoration, responds to increased oncogenic signalling to mediate tumour regression. Our observations also underscore that the p53 pathway is not engaged by low levels of oncogene activity that are sufficient for early stages of lung tumour development. These data suggest that restoration of pathways important in tumour progression, as opposed to initiation, may lead to incomplete tumour regression due to the stage-heterogeneity of tumour cell populations.National Cancer Institute (U.S.) (Cancer Center Support Grant P30-CA14051)American Cancer Society (New England Area Fellow)Leukemia & Lymphoma Society of America (Fellow)Massachusetts Institute of Technology. Undergraduate Research Program (John Reed Fund)Damon Runyon Cancer Research Foundation (Merck Fellow)Genentech, Inc. (Postdoctoral Fellow)Howard Hughes Medical Institut