251 research outputs found
The sulfur pathway and diagnosis of sulfate depletion in grapevine
Sulfur is an essential nutrient to all plant species. Plants assimilate sulfur
in a well-described pathway, which has been taken up by roots. Regulatory mech-
anism has been the subject of many research papers. However, recent studies
highlighted differences between crop plants and the model plant Arabidopsis
thaliana. Our work focuses on the identification of genes involved in the sulfur
metabolism in the Vitis vinifera genome, and their response to sulfur deficiency and
other abiotic stress endured by grapevine in the field, namely water stress. Here, we
describe the identification and brief characterization of the first assimilation
enzymes involved in the sulfur pathway, the enzyme responsible for sulfur activa-
tion, ATP sulfurylase (ATPS), and the two enzymes that reduce sulfate to sulfide,
Adenosine 50-phosphosulate reductase (APR) and Sulfite reductase (SiR). A reduc-
tion was observed in the number of ATPS and APR isoforms identified in
V. vinifera genome when compared to A. thaliana or Glycine max genomes. Two
ATPS isoforms were present in the Vitis genome, of which only ATPS1 transcript
was detected in the tested tissues, and one APR isoform, suggesting an absence of
redundancy in the role of both enzymes. ATPS1, APR and SiR transcript level was
up-regulated in response to 2 days exposure to sulfur deficiency in V. vinifera cell
cultures, which was completely reversed by the addition of GSH to the culture
medium. Apparently, oxidative stress triggered GSH has a pivotal role in the
regulation of ATPS1, APR and SiR transcription level, since their up-regulation
was observed in mRNA from field grapevine berries under water stress, which is
known to induce oxidative stress.info:eu-repo/semantics/publishedVersio
Effects of external nutrient sources and extreme weather events on the nutrient budget of a Southern European coastal lagoon
The seasonal and annual nitrogen (N), phosphorus (P), and carbon (C) budgets of the mesotidal Ria Formosa lagoon, southern Portugal, were estimated to reveal the main inputs and outputs, the seasonal patterns, and how they may influence the ecological functioning of the system. The effects of extreme weather events such as long-lasting strong winds causing upwelling and strong rainfall were assessed. External nutrient inputs were quantified; ocean exchange was assessed in 24-h sampling campaigns, and final calculations were made using a hydrodynamic model of the lagoon. Rain and stream inputs were the main freshwater sources to the lagoon. However, wastewater treatment plant and groundwater discharges dominated nutrient input, together accounting for 98, 96, and 88 % of total C, N, and P input, respectively. Organic matter and nutrients were continuously exported to the ocean. This pattern was reversed following extreme events, such as strong winds in early summer that caused upwelling and after a period of heavy rainfall in late autumn. A principal component analysis (PCA) revealed that ammonium and organic N and C exchange were positively associated with temperature as opposed to pH and nitrate. These variables reflected mostly the benthic lagoon metabolism, whereas particulate P exchange was correlated to Chl a, indicating that this was more related to phytoplankton dynamics. The increase of stochastic events, as expected in climate change scenarios, may have strong effects on the ecological functioning of coastal lagoons, altering the C and nutrient budgets.Portuguese Science and Technology Foundation (FCT) [POCI/MAR/58427/2004, PPCDT/MAR/58427/2004]; Portuguese Science and Technology Foundation (FCT
Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at ās = 7 TeV with the ATLAS detector
This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of ās = 7 TeV;{\rm Te}{\rm V}4.6\;{\rm f}{{{\rm b}}^{-1}}{{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}|\eta |\lt 1.9{{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques
Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at sā=8 TeV with the ATLAS detector
The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fbā1 of protonāproton collision data at ās = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via tĖātĻĖ01 or tĖā bĻĖĀ±1 ābW(ā)ĻĖ01 , where ĻĖ01 (ĻĖĀ±1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of tĖ ā tĻĖ01 . For a branching fraction of 100%, top squark masses in the range 270ā645 GeV are excluded for ĻĖ01 masses below 30 GeV. For a branching fraction of 50% to either tĖ ā tĻĖ01 or tĖ ā bĻĖĀ±1 , and assuming the ĻĖĀ±1 mass to be twice the ĻĖ01 mass, top squark masses in the range 250ā550 GeV are excluded for ĻĖ01 masses below 60 GeV
Dental sealant knowledge, opinion, values and practice of Spanish dentists
[Background]
Multiple guidelines and systematic reviews recommend sealant use to reduce caries risk. Yet, multiple reports also indicate that sealants are significantly underutilized. This study examined the knowledge, opinions, values, and practice (KOVP) of dentists concerning sealant use in the southwest region of Andalusia, Spain. This is a prelude to the generation of a regional plan for improving childrenās oral health in Andalusia.[Methods]
The surveyās target population was dentists working in western Andalusia, equally distributed in the provinces of Seville, Cadiz, and Huelva (N=2,047). A convenience sample of meeting participants and meeting participant email lists (N=400) were solicited from the annual course on Community and Pediatric Dentistry. This course is required for all public health sector dentists, and is open to all private sector dentists. Information on the dentistās KOVP of sealants was collected using four-part questionnaire with 31, 5-point Likert-scaled questions.[Results]
The survey population demographics included 190 men (48%) and 206 women (52%) with an average clinical experience of 10.6 (Ā± 8.4) years and 9.3 (Ā± 7.5) years, respectively. A significant sex difference was observed in the distribution of place of work (urban/suburb) (p=0.001), but no sex differences between working sector (public/private). The mean Ā± SD values for each of the four KOVP sections for pit and fissure sealants were: knowledge = 3.57 Ā± 0.47; opinion = 2.48 Ā± 0.47; value = 2.74 Ā± 0.52; and practice = 3.48 Ā± 0.50. No sex differences were found in KOVP (all p >0.4). Independent of sex: knowledge statistically differed by years of experience and place of work; opinion statistically differed by years of experience and sector; and practice statistically differed by years of experience and sector. Less experienced dentists tended to have slightly higher scores (~0.25 on a Likert 1ā5 scale). Statistically significant correlations were found between knowledge and practice (r=0.44, p=0.00) and between opinion and value (r=0.35, p=0.00).[Conclusions]
The results suggest that, similar to other countries, Andalusian dentists know that sealants are effective, have neutral to positive attitudes toward sealants; though, based on epidemiological studies, underuse sealants. Therefore, methods other than classical behavior change (eg: financial or legal mechanisms) will be required to change practice patterns aimed at improving children's oral health.We acknowledge the following sources for invaluable financial support NIMHD 1 R34 DE022272 (NIH2385) and NIDCR 1 U24 MD006964
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