294 research outputs found
A global glacial ocean state estimate constrained by upper-ocean temperature proxies
Author Posting. © American Meteorological Society, 2018. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 31 (2018): 8059-8079, doi:10.1175/JCLI-D-17-0769.1.We use the method of least squares with Lagrange multipliers to fit an ocean general circulation model to the Multiproxy Approach for the Reconstruction of the Glacial Ocean Surface (MARGO) estimate of near sea surface temperature (NSST) at the Last Glacial Maximum (LGM; circa 23â19 thousand years ago). Compared to a modern simulation, the resulting global, last-glacial ocean state estimate, which fits the MARGO data within uncertainties in a free-running coupled oceanâsea ice simulation, has global-mean NSSTs that are 2°C lower and greater sea ice extent in all seasons in both the Northern and Southern Hemispheres. Increased brine rejection by sea ice formation in the Southern Ocean contributes to a stronger abyssal stratification set principally by salinity, qualitatively consistent with pore fluid measurements. The upper cell of the glacial Atlantic overturning circulation is deeper and stronger. Dye release experiments show similar distributions of Southern Ocean source waters in the glacial and modern western Atlantic, suggesting that LGM NSST data do not require a major reorganization of abyssal water masses. Outstanding challenges in reconstructing LGM ocean conditions include reducing effects from model biases and finding computationally efficient ways to incorporate abyssal tracers in global circulation inversions. Progress will be aided by the development of coupled oceanâatmosphereâice inverse models, by improving high-latitude model processes that connect the upper and abyssal oceans, and by the collection of additional paleoclimate observations.DEA was supported by a NSF Graduate Research Fellowship
and NSF Grant OCE-1060735. OM acknowledges
support from the NSF. GF was supported by
NASA Award 1553749 and Simons Foundation Award
549931
Improving cereal productivity and farmersâ income using a strategic application of fertilizers in West Africa
In the past two years, ICRISAT, in collaboration with other International Agricultural Research Centres, National Agricultural Research and Extension Systems, has been evaluating and promoting point or hill application of fertilizer along with âWarrantageâ in three West African countries, namely, Burkina Faso, Mali and Niger. The hill application of fertilizers consists of applying small doses of fertilizer in the planting hills of millet and sorghum. The combination of strategic hill application of fertilizer with complementary institutional and market linkages, through an inventory credit system (known as âWarrantageâ) offers a good opportunity to improve crop productivity and farmersâ incomes. Results from the two year on-farm trials showed that, on average, in all the three countries, grain yields of millet and sorghum were greater by 44 to 120% while incomes of farmers increased by 52 to 134% when using hill application of fertilizer than with the earlier recommended fertilizer broadcasting methods and farmersâ practice. Substantial net profits were obtained by farmers using âWarrantageâ. Farmersâ access to credit and inputs was improved substantially through the âWarrantageâ system. The technology has reached up to 12650 farm households in the three countries and efforts are in progress to further scale-up and out the technology to wider geographical area
Evolution of Metastasis Study Models toward MetastasisOn-A-Chip: The Ultimate Model?
For decades, several attempts have been made to obtain a mimetic model for
the study of metastasis, the reason of most of deaths caused by cancer, in
order to solve the unknown phenomena surrounding this disease. To better
understand this cellular dissemination process, more realistic models are
needed that are capable of faithfully recreating the entire and essential tumor
microenvironment (TME). Thus, new tools known as tumor-on-a-chip and
metastasis-on-a-chip have been recently proposed. These tools incorporate
microfluidic systems and small culture chambers where TME can be faithfully
modeled thanks to 3D bioprinting. In this work, a literature review has been
developed about the different phases of metastasis, the remaining unknowns
and the use of new models to study this disease. The aim is to provide a
global vision of the current panorama and the great potential that these
systems have for in vitro translational research on the molecular basis of the
pathology. In addition, these models will allow progress toward a personalized medicine, generating chips from patient samples that mimic the original
tumor and the metastatic process to perform a precise pharmacological
screening by establishing the most appropriate treatment protocol.Ministerio de Educacion y Formacion Profesional
FPU19/02138
BOE-B-2019-44783Ph.D. program of Biomedicine of the University of GranadaConsejeria de Economia, Conocimiento, Empresas y Universidad, Junta de Andalucia (FEDER Funds)
P18-FR-2470
B-CTS-230-UGR18
SOMM17/6109/UGRInstituto de Salud Carlos III (FEDER Funds)
PIE16-00045
DTS19/00145Junta de Andalucia
PIN-0224-2019Chair "Doctors Galera-Requena in cancer stem cell research"
CMC-CTS96
Interface flow process audit: using the patient's career as a tracer of quality of care and of system organisation
OBJECTIVES: This case study aims to demonstrate the method's feasibility and capacity to improve quality of care. Several drawbacks attached to tracer condition and selected procedure audits oblige clinicians to rely on external evaluators. Interface flow process audit is an alternative method, which also favours integration of health care across institutions divide. METHODS: An action research study was carried out to test the feasibility of interface flow process audit and its impact on quality improvement. An anonymous questionnaire was carried out to assess the participants' perception of the process. RESULTS: In this study, interface flow process audit brought together general practitioners and hospital doctors to analyse the co-ordination of their activities across the primary-secondary interface. Human factors and organisational characteristics had a clear influence on implementation of the solutions. In general, the participants confirmed that the interface flow process audit helped them to analyse the quality of case management both at primary and secondary care level. CONCLUSIONS: The interface flow process audit appears a useful method for regular in-service self-evaluation. Its practice enabled to address a wide scope of clinical, managerial and economical problems. Bridging the primary-secondary care gap, interface flow process audit's focus on the patient's career combined with the broad scope of problems that can be analysed are particularly powerful features. The methodology would benefit from an evaluation of its practice on larger scale
Synthesis and structure - Activity relationship study of potent cytotoxic analogues of the marine alkaloid Lamellarin D
The marine alkaloid, Lamellarin D (Lam-D), has shown potent cytotoxicity in numerous cancer cell lines, and was recently identified as a potent topoisomerase I inhibitor. A library of open lactone analogs of Lam-D was prepared from a methyl 5,6-dihydropyrrolo[2,1-a]isoquinoline-3- carboxylate scaffold (1) by introducing various aryl groups through sequential and regioselective bromination, followed by Pd(0)-catalyzed Suzuki cross-coupling chemistry. The compounds were obtained in a 24-44% overall yield, and tested in a panel of three human tumor cell lines, MDA-MB- 231 (breast), A-549 (lung), and HT-29 (colon), to evaluate their cytotoxic potential. From these data the SAR study concluded that more than 75% of the open-chain Lam-D analogs tested showed cytotoxicity in a low micromolar GI50 range
Influence of Sahelian and Sudanian provenances on the physical and mechanical properties of Faidherbia albida wood from Chad
Faidherbia albida is a typical emblematic species of African dryland areas. In Chad, it is used for many purposes, but very little is known about the technological properties of its wood, which sometimes
leads to inappropriate uses. This work consisted to study the physical and mechanical properties of this wood, collected in the Sahelian and Sudanian chadian zone. As well as the impact study of the
sampling areas of these properties. The result obtained shows that, the density, infradensity; modulus of elasticity, compression strength were significantly higher in the Sahelian zone than in the Sudanian
zone, i.e. 508 and 409 kg·mâ3 ; 5555 and 23.7 MPa, compared to 444 and 359 kg·mâ3 ; 4150 and 19.6 MPa. The total tangential shrinkage, total volumetric shrinkage, fibre saturation point; static
bending strength were significantly lower in wood from the Sahelian zone compared to the Sudanian zone, i.e. 4.6%, 7.7%, 23.7%; 42.5 MPa, compared to 6.6%, 9.5%, 28.9%; 52.6 MPa. The total radial
shrinkage values obtained were not significantly different between the two provenances (mean: 3.1%)
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