224 research outputs found
Comparison of two methods of herbage production measurement in continuously grazed hill pastures : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in Animal Science at Massey University
Herbage production of continuously grazed hill country pastures has traditionally been measured using grazing exclusion cages and a trim technique. Herbage production values obtained via this system differ from those of the surrounding grazed sward due to differences in sward structure. Herbage production of four farmlets with differing fertiliser treatments was measured by two methods over a full year. The first method involved a computer model which calculated herbage production from dry matter intake and cover change. Secondly, herbage production was measured via frame cuts, and the results of the two methods compared. The model measured less herbage production than the frames on an annual basis in all four fertiliser treatments (0.77 of frame average for the four fertiliser treatments). The ratio of model to frame herbage production varied widely during the year, with maximum ratios of model to frame herbage production of 1.6 occurring in autumn, and the minimum of -0.02 in winter. More herbage was produced under the frames in spring than in the grazed sward as a result of increased expression of reproductive tillers under the frames than in the grazed sward. Frames appear to underestimate herbage production in dry conditions as the trimming off of herbage at the placement of frames leads to lower levels of plant available water when compared to the surrounding sward. The low ratios are a result of the large amounts of dead material which build up in grazed hill pastures over summer and the rapid breakdown of this material when conditions are right, in this case in early-late winter. The results suggest that there are large differences in the annual, and seasonal pattern of herbage production between that measured off grazed swards and that measured via frames. This suggests that anyone wishing to calculate expected pasture supply using frame cut information must modify frame cut values to determine production of a continuously grazed sward
Accelerating and enabling convergence of nonlinear solvers for Navier-Stokes equations by continuous data assimilation
This paper considers improving the Picard and Newton iterative solvers for
the Navier-Stokes equations in the setting where data measurements or solution
observations are available. We construct adapted iterations that use continuous
data assimilation (CDA) style nudging to incorporate the known solution data
into the solvers. For CDA-Picard, we prove the method has an improved
convergence rate compared to usual Picard, and the rate improves as more
measurement data is incorporated. We also prove that CDA-Picard is contractive
for larger Reynolds numbers than usual Picard, and the more measurement data
that is incorporated the larger the Reynolds number can be with CDA-Picard
still being contractive. For CDA-Newton, we prove that the domain of
convergence, with respect to both the initial guess and the Reynolds number,
increases as as the amount of measurement data is increased. Additionally, for
both methods we show that CDA can be implemented as direct enforcement of
measurement data into the solution. Numerical results for common benchmark
Navier-Stokes tests illustrate the theory
Microtubule-severing enzymes: From cellular functions to molecular mechanism.
Microtubule-severing enzymes generate internal breaks in microtubules. They are conserved in eukaryotes from ciliates to mammals, and their function is important in diverse cellular processes ranging from cilia biogenesis to cell division, phototropism, and neurogenesis. Their mutation leads to neurodegenerative and neurodevelopmental disorders in humans. All three known microtubule-severing enzymes, katanin, spastin, and fidgetin, are members of the meiotic subfamily of AAA ATPases that also includes VPS4, which disassembles ESCRTIII polymers. Despite their conservation and importance to cell physiology, the cellular and molecular mechanisms of action of microtubule-severing enzymes are not well understood. Here we review a subset of cellular processes that require microtubule-severing enzymes as well as recent advances in understanding their structure, biophysical mechanism, and regulation
Teaching Behavioral Pain Management to Healthcare Professionals: A Systematic Review of Research in Training Programs
Pain is a common and potentially debilitating condition. Whereas there is vast literature on developmentally appropriate behavioral techniques for pain management, results of curriculum evaluations and knowledge surveys reveal a dearth of awareness of these strategies in healthcare professionals. As a result, the development and evaluation of pain management training programs is an important endeavor. Results of studies evaluating such programs are promising and suggest that training may be an effective means of impacting healthcare professionalsβ knowledge, attitudes, and even patient care. These results must be interpreted with caution however, as the literature contains several conceptual and methodological limitations. These limitations, in combination with the wide diversity in program components, format of delivery, and research methods preclude definitive conclusions on the most practical and effective means to provide training. To address this question, further systematic work on the development and evaluation of pain management training programs is warranted
Breaks and the Statistical Process of Inflation:The Case of Estimating the βModernβ Long-Run Phillips Curve*
E-Cadherin Acts as a Regulator of Transcripts Associated with a Wide Range of Cellular Processes in Mouse Embryonic Stem Cells
We have recently shown that expression of the cell adhesion molecule E-cadherin is required for LIF-dependent pluripotency of mouse embryonic stem (ES) cells.In this study, we have assessed global transcript expression in E-cadherin null (Ecad-/-) ES cells cultured in either the presence or absence of LIF and compared these to the parental cell line wtD3.We show that LIF has little effect on the transcript profile of Ecad-/- ES cells, with statistically significant transcript alterations observed only for Sp8 and Stat3. Comparison of Ecad-/- and wtD3 ES cells cultured in LIF demonstrated significant alterations in the transcript profile, with effects not only confined to cell adhesion and motility but also affecting, for example, primary metabolic processes, catabolism and genes associated with apoptosis. Ecad-/- ES cells share similar, although not identical, gene expression profiles to epiblast-derived pluripotent stem cells, suggesting that E-cadherin expression may inhibit inner cell mass to epiblast transition. We further show that Ecad-/- ES cells maintain a functional Ξ²-catenin pool that is able to induce Ξ²-catenin/TCF-mediated transactivation but, contrary to previous findings, do not display endogenous Ξ²-catenin/TCF-mediated transactivation. We conclude that loss of E-cadherin in mouse ES cells leads to significant transcript alterations independently of Ξ²-catenin/TCF transactivation
Genomic Restructuring in the Tasmanian Devil Facial Tumour: Chromosome Painting and Gene Mapping Provide Clues to Evolution of a Transmissible Tumour
Devil facial tumour disease (DFTD) is a fatal, transmissible malignancy that threatens the world's largest marsupial carnivore, the Tasmanian devil, with extinction. First recognised in 1996, DFTD has had a catastrophic effect on wild devil numbers, and intense research efforts to understand and contain the disease have since demonstrated that the tumour is a clonal cell line transmitted by allograft. We used chromosome painting and gene mapping to deconstruct the DFTD karyotype and determine the chromosome and gene rearrangements involved in carcinogenesis. Chromosome painting on three different DFTD tumour strains determined the origins of marker chromosomes and provided a general overview of the rearrangement in DFTD karyotypes. Mapping of 105 BAC clones by fluorescence in situ hybridisation provided a finer level of resolution of genome rearrangements in DFTD strains. Our findings demonstrate that only limited regions of the genome, mainly chromosomes 1 and X, are rearranged in DFTD. Regions rearranged in DFTD are also highly rearranged between different marsupials. Differences between strains are limited, reflecting the unusually stable nature of DFTD. Finally, our detailed maps of both the devil and tumour karyotypes provide a physical framework for future genomic investigations into DFTD
Alveolar Rhabdomyosarcoma with Regional Nodal Involvement: Results of a Combined Analysis from Two Cooperative Groups
BACKGROUND: Treatment of children and adolescents with alveolar rhabdomyosarcoma (ARMS) and regional nodal involvement (N1) have been approached differently by North American and European cooperative groups. In order to define the better therapeutic strategy, we analyzed two studies conducted between 2005 and 2016 by the European paediatric Soft tissue sarcoma Study Group (EpSSG) and Childrenβs Oncology Group (COG). METHODS: We retrospectively identified patients with ARMS-N1 enrolled in either EpSSG RMS2005 or in COG ARST0531. Chemotherapy in RMS2005 comprised IVADo (ifosfamide, vincristine, dactinomycin, doxorubicin), IVA and maintenance (vinorelbine, cyclophosphamide); in ARST0531 it consisted on either VAC (vincristine, dactinomycin, cyclophosphamide) or VAC alternating with VI (vincristine, irinotecan). Local treatment was similar in both protocols. RESULTS: The analysis of the clinical characteristics of 239 patients showed some differences between study groups: in RMS2005, advanced IRS Group and large tumors predominated. There were no differences in outcomes between the two groups: 5-year event-free survival (EFS), 49%(95%CI=39β59) and 44%(95%CI=30β58), and overall survival (OS), 51%(95%CI=41β61) and 53.6%(95%CI=40β68), in RMS2005 and ARST0531, respectively. In RMS2005, EFS of patients with FOXO1-positive tumors was significantly inferior to those FOXO1-negative (49.3% vs 73%, p=0.034). In contrast, in ARST0531, EFS of patients with FOXO1-positive tumors was 45% compared with 43.8% for those FOXO1-negative. CONCLUSIONS: The outcome of patients with ARMS N1 was similar in both protocols. However, patients with FOXO1 fusion-negative tumors enrolled in RMS2005 showed a significantly better outcome, suggesting that different strategies of chemotherapy may have an impact in the outcome of this subgroup of patients
Metabolic Response as Assessed by 18F-Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Does Not Predict Outcome in Patients with Intermediate- or High-Risk Rhabdomyosarcoma: A Report from the Children's Oncology Group Soft Tissue Sarcoma Committee
Cross-cutting principles for planetary health education
Since the 2015 launch of the Rockefeller Foundation Lancet Commission on planetary health,1 an enormous groundswell of interest in planetary health education has emerged across many disciplines, institutions, and geographical regions. Advancing these global efforts in planetary health education will equip the next generation of scholars to address crucial questions in this emerging field and support the development of a community of practice. To provide a foundation for the growing interest and efforts in this field, the Planetary Health Alliance has facilitated the first attempt to create a set of principles for planetary health education that intersect education at all levels, across all scales, and in all regions of the worldβie, a set of cross-cutting principles
- β¦