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This work aimed to investigate the partial K-replacement by Na supply to alleviate drought-induced stress in Eucalyptus species. Plant growth, leaf gas exchange parameters, water relations, oxidative stress (H2O2 and MDA content), chlorophyll concentration, carbon (C) and nitrogen (N) isotopic leaf composition (δ13C and δ15N) were analyzed. Drought tolerant E. urophylla and E. camaldulensis showed positive responses to the partial K substitution by Na, with similar dry mass yields, stomatal density and total stomatal pore area relative to the well K-supplied plants under both water conditions, suggesting that 50% of the K requirements is pressing for physiological functions that is poorly substituted by Na. Furthermore, E. urophylla and E. camaldulensis up-regulated leaf gas exchanges, leading to enhanced long-term water use efficiency (WUEL). Moreover, the partial K substitution by Na had no effects on plants H2O2, MDA, δ13C and δ15N, confirming that Na, to a certain extent, can effectively replace K in plants metabolism. Otherwise, the drought-sensitive E. saligna species was negatively affected by partial K replacement by Na, decreasing plants dry mass, even with up-regulated leaf gas exchange parameters. The exclusive Na-supplied plants showed K-deficient symptoms and lower growth, WUEL, and δ13C, besides higher Na accumulation, δ15N, H2O2 and MDA content.

Mineral soils are usually considered inappropriate for pollen analysis because of the poor quality of pollen and spore preservation and the disturbed stratigraphy. However, here we present a 57 cm core, collected from a waterlogged sandy soil in the lowland Atlantic Forest of SE Brazil, which shows good stratigraphy and good preservation of pollen and spores since ~ 7000 cal. BP, both in organic and in mineral horizons. By the other hand, the decomposition of the organic matter and its translocation along the soil profile led to changes of C and N results (TOC, TN, C/N, δ13C and δ15N). Mid-Holocene paleoclimate inferences from this study are in accordance with climate fluctuations presented in previous studies for Central, Southeastern and Southern Brazil, when a change to more humid climate occurred at ~ 7000 cal BP. The process responsible for the presence of biological proxies along this sandy soil profile involves the continuous deposition of these proxies together with litter and sand, and the subsequent decomposition of the litter. Ultimately, this process led to the vertical accretion of the sand with the more resistant organic structures preserved in stratigraphic sequence. The preservation of pollen and spores along the profile is probably caused by low pH and redoximorphic conditions due to water saturation. This study suggests the potential for retrieving useful paleoecological information from mineral and organic horizons of tropical waterlogged sandy soils, which is especially useful for those regions where traditional pollen archives (lakes and peat bogs) are absent.

The so-called “enhanced-efficiency N fertilizers” were developed to mitigate ammonia losses from surface-applied urea (UR) and thereby increase N use efficiency and crop yield. However, research is needed to assess the efficiency of these products in mitigating ammonia emission. The aim of this study was to compare volatilization losses of ammonia following application of UR treated with B and Cu (B-Cu-UR), UR treated with dicyandiamide (DCD) and N-(n-butyl) thiophosphoric triamide (NBPT) (DCD-NBPT-UR), UR treated with humic substances (HS-UR), UR treated with NBPT (NBPT-UR), polymer S-coated UR (PSCUR), S-coated UR (SCUR), and untreated and uncoated UR (UR). Fertilizers (at a rate of 2355 mg N kg−1) were applied over the soil surface, and volatilized ammonia was quantified for 60 d under controlled conditions using a static closed chamber. Use of DCD-NBPT-UR increased ammonia emissions in comparison to UR by blocking nitrification and keeping the soil pH high, the latter resulting from UR hydrolysis. Urease complexation by the inhibitor and gradual N release resulted in low losses of ammonia by NBPT-UR and PSCUR, respectively. Compared to UR, B Cu-UR delayed and slightly decreased ammonia volatilization. HS-UR, SCUR, and UR fertilizers had similar ammonia losses. Humic substances most likely did not act on urea-N complexation or even on decreasing urease activity, whereas immediate release of the nutrient by SCUR was noted. NBPT-UR and PSCUR could substitute for UR, aiming to mitigate ammonia volatilization.

Mangroves are key ecosystems which respond to global changes in tropical and subtropical regions worldwide. We describe late Holocene mangroves that established close to the southernmost limit (28°S) for this type of ecosystem in South America. Our findings are based on a C dated core obtained from Babitonga Bay, Santa Catarina State, Brazil (26°12′S, 48°33′W). Analysis of palynology, sedimentary facies, isotopic and elemental data shows that mangrove establishment took place ~500 yrs. B.C.E., following an increase in humidity, and expanded further during the Roman Warm Period and at the end of Dark Age Cold Period. Mangrove and precipitation proxies records appear to be sensitive to rainfall patterns imposed both by the expansion/retraction of the Intertropical Convergence Zone and also the interaction with the South Atlantic Subtropical Anticyclone which affects coastal region due to sea surface temperature variations., The authors thank the Coastal Dynamic Laboratory (LADIC-UFPA) , C-14 Laboratory of the Center for Nuclear Energy in Agriculture (CENA-USP) , University of Joinville (UNIVILLE) and Radiocarbon Laboratory (LAC-UFF) for all infrastructure and support. We also thank three anonymous Reviewers and Prof. H. Falcon-Lang for their constructive comments. The first and third author thanks Brazilian Council for Technology and Science-CNPq for fellowship (process 131813/2016-1 , 165911/2015-8 and 305074/2017-2 ). This study was financed by CNPq ( 445111/2014-3 , 405060/2013- 0 ) and FAPESP ( 2011/00995-7 , 2017/03304-1, and 2020/13715-1 ). This study also was financed in part by the Coordenação de Aperfeiçoamento de Pessoal Nível Superior – Brazil (CAPES) – Finance Code 001 .

The objective of this study was to quantify the effect of potassium (K) supply on osmotic adjustment and drought avoidance mechanisms of Eucalyptus seedlings growing under short-term water stress. The effects of K supply on plant growth, nutritional status, leaf gas exchange parameters, leaf water potential (Ψw), leaf area (LA), stomatal density (SD), leaf carbon (C) and nitrogen (N) isotopic compositions (δ13C and δ15N ‰) and leaf C/N ratio under polyethylene glycol (PEG)-induced water deficit were measured. Under both control (non-PEG) and osmotic stress (+PEG) conditions, K supply increased plant growth, boosting dry matter yield with decreased C/N leaf ratio and δ15N ‰ values. The +PEG significantly reduced LA, plant growth, dry matter yield, Ψw, number of stomata per plant and leaf gas exchange, relative to non-PEG condition. Potassium supply alleviated osmotic-induced alterations in Eucalyptus seedlings by better regulating leaf development as well as SD, thus improving the rate of leaf gas exchange parameters, mesophyll conductance to CO2 (lower δ13C ‰ values) and water use efficiency (WUE). Consequently, K-supplied plants under drought better acclimated to osmotic stress than K-deficient plants, which in turn induced lower CO2 assimilation and dry matter yield, as well as higher leaf δ13C ‰ and δ15N ‰ values. In conclusion, management practices should seek to optimize K-nutrition to improve WUE, photosynthesis-related parameters and plant growth under water deficit conditions.

Made available in DSpace on 2020-12-12T01:30:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Temperature influences the global distribution of mangroves, and global warming may be causing a poleward mangrove expansion. Sedimentary features, pollen, and isotopes data from six sediment cores, as well as 14C datings, indicated a marine transgression during the Holocene, and it contributed to the expansion of tidal flats occupied by saltmarshes. Environmental conditions suitable for mangroves development occurred on the study site during the Holocene, but, according to 210Pb and 14C dating, the establishment of mangroves mainly represented by Laguncularia trees only began between ~1957 and ~1986 (AD) on the studied tidal flats. Spatial-temporal analysis, based on satellite and drone images, revealed a mangrove expansion of ~10 ha in the study area between 2003 (96.1 ha) and 2019 (106.1 ha). Nowadays, in the study area, saltmarshes, mainly characterized by Spartina and Acrostichum, are sharing tidal flats with mangroves, represented by Laguncularia (≤5 m tall) and Avicennia (≤11 m tall). Probably, the absence of mangroves during the Holocene, followed by their establishment and expansion during the Anthropocene in the subtropical zone, is associated with a migration of the austral mangrove limit into the temperate zone, caused by the gradual increase in winter temperatures. This process may be related to a poleward mangrove migration since the late Holocene, caused by a natural Holocene global warming. However, the industrial-era warming must have intensified the mangrove expansion into temperate zones. Graduate Program of Geology and Geochemistry Federal University of Pará, Av. Perimentral 2651, Terra Firme University of São Paulo CENA/14C Laboratory, Av. Centenário 303 Federal Institute of Pará, Av. Alm. Barroso, 1155, Marco Instituto de Geociências e Ciências da Terra Universidade Estadual Paulista Júlio de Mesquita Filho-UNESP University of São Paulo CENA/Stable Isotopes Laboratory, São Paulo Instituto de Geociências e Ciências da Terra Universidade Estadual Paulista Júlio de Mesquita Filho-UNESP FAPESP: 2011/00995-7 FAPESP: 2017/03304-1

Globally, mangroves are expected to move inland as sea-level rises. However, local characteristics mainly related to mangrove structure, geomorphology and coastal hydrodynamics may change the mangrove response to sea-level rise. The most useful evidence to support projections for the future likely comes from mangrove history reconstruction corresponding to past sea-level changes. This study characterized modern (1985–2018 CE) and past (

Generally, palaeoenvironmental interpretations consider only allogenic processes, when autogenic factors may have a strong influence on proxies of stratigraphic sequences. For instance, the Holocene history of the vegetation along the southern littoral of the State of Bahia in north-eastern Brazil is characterized by mangrove dynamics controlled by allogenic processes. However, over smaller timescales (~700 years), autogenic processes may have controlled vegetation dynamics and hence observed pollen distribution. This work proposes tidal channel dynamics as one of the main cause for changes in pollen assemblage along the studied stratigraphic profiles during the last centuries, based on sedimentology, pollen and elemental analysis (δ13C, δ15N and C/N) and radiocarbon dating of sedimentary organic matter from two cores sampled from an abandoned meander and a tidal flat at the mouth of the Jucurucu River. One core was sampled from a mangrove formed during the past ~550 cal yr bp. Another core recorded sediments in a varzea forest (swamp seasonally and permanently inundated by freshwater) located ~2.7 km from the current shoreline, which displayed a maximum age of ~680 cal yr bp. Two facies associations were identified: tidal channel (A) and tidal flat/oxbow lake (B). This work proposes allogenic processes as the main driving forces controlling the wetlands dynamics at the studied site during the Holocene. However, our data also reveal that part of the changes in vegetation over the last ~700 years reflect tidal channels and tidal flats development, which represent autogenic processes. The change in timescale analysis from the Holocene to recent centuries may have weakened the influence of allogenic factors. However, this needs interpretation with reference to the spatial scale of the depositional environment as the larger the depositional system analyzed, the stronger the influence of autogenic processes on stratigraphic sequences over longer timescales. Copyright © 2017 John Wiley & Sons, Ltd.

The aim of this paper is to evaluate the compatibility between the Holocene relative sea-level (RSL) curves proposed for the Brazilian littoral and mangrove dynamics along a fluvial valley in the state of southern Bahia. This was done integrating geomorphological, sedimentological, palynological, and stable isotopic data from two cores collected at the mouth of the Jucuruçu River and at a site 23 km inland, near the city of Prado, northeastern Brazil. Core PR07, sampled from a fluvial plain at about 4.5±1 m above the RSL, reveals mangrove pollen (5–20%) and estuarine/terrestrial organic matter (δ13C=~–25‰, C/N=7.3–67) between 4.5 m (~7400 cal yr BP) and 1.75 m depth (~5350 cal yr BP). Core PR11, sampled from a mangrove tidal flat, also revealed mangrove pollen taxa (5-28%) since 660 cal yr BP. Core PR07 indicated absence of mangrove pollen and increase of sedimentary organic matter sourced from terrestrial C3 plants (δ13C=~–27‰, C/N=22–159) during the last 5350 cal yr BP. Probably, the changes in vegetation and sedimentary organic matter identified in core PR07 were caused by the combined effects of the RSL fluctuations, with a highstand at about 5350 cal yr BP of 2.7±1.35 m, and changes in fluvial discharge.

The objective of this work was to exclusively improve the management of wastes constituted mainly by organic solvents, due to the opportunities for improvements in the processing of such substances in the institution where the studies were realized. By means of the tests carried out in the distillation system using acetone as a reference, advantages and disadvantages were found with increasing/decreasing the temperature used in the process. From the use of gas chromatography, it was possible to obtain a more precise control of the quality of the recovered product and also to verify the high efficiency of the distillation process in the separation of the solvent from the other contaminants present in the waste. And in terms of comparison of treatments, distillation proved to be environmentally more sustainable and about 8 times more economical than incineration.

Molecular nitrogen (N2) and nitrous oxide (N2O) generated by denitrification increase N losses in the soil–plant system. This study aimed to quantify N2 and N2O from potassium nitrate (K15NO3) applied to soils with different textures and moisture contents in the absence and presence of a source of carbon (C) using the 15N tracer method. In the three soils used (sandy texture (ST), sandy clay loam texture (SCLT), and clayey texture (CT)), three moisture contents were evaluated (40%, 60%, and 80% of the water holding capacity (WHC)) with (D+) and without (D−) dextrose added. The treatments received 100 mg N kg−1 (KNO3 with 23.24 atom% 15N). N2 emissions occurred in all of the treatments, but N2O emissions only occurred in the D+ treatment, showing increases with increasing moisture content. SCLT with 80% WHC in the D+ treatment exhibited the highest accumulated N emission (48.26 mg kg−1). The 15N balance suggested trapping of the gases in the soil.

This study demonstrates the usefulness of palynofacies as a tool for characterizing the origin, transport, and settling of particulate organic matter preserved in fluvial plain sediments and its integration with diatoms for inferring past depositional environments. Palynofacies, diatoms, and organic geochemistry (S, C/S) data from a sediment core (PR07) collected from the Jucurucu River valley in coastal southern Bahia, northeastern Brazil were used to better understand ecosystem changes that occurred in the region during the last ~7.5k years. Elemental values (S: 0.15–5.9%; C/S: 0.12–41.5) suggest marine and fluvial influences in the valley during the Holocene, and organic matter was derived from freshwater and marine phytoplankton. The presence of heterolithic deposits, brackish/marine diatoms, predominance of amorphous group, non-opaque phytoclasts, pyrite crystals, and marine microfossils suggests that a tidal flat formed during a mid-Holocene sea-level highstand. A fluvial plain developed in the last 5k years, due to marine regression and an increase in fluvial sediment supply to the region.

The Atlantic Rainforest, covering the area from northern Espirito Santo to Southern Bahia states, has been considered as a stable forest during Pleistocene Glacial times. Aside from modelling and phylogenetic studies, this hypothesis has never been tested with empirical, fossil pollen, paleo-vegetation data. By using palynology, radiocarbon dating, and carbon and nitrogen elemental and isotopic analyses of organic matter, we reconstructed the vegetation dynamics and inferred climatic changes since the Late Pleistocene in the centre of this global biodiversity hotspot. Our results show that the forest biome was resilient to Last Glacial Maximum - LGM conditions, but that the floristic composition differed from that of today. Since the late glacial, the floristic composition of the dense forest changed from cold- to warm-adapted taxa. Structural, as well as floristic, changes occurred during drier conditions of the early and middle Holocene, with an opening of the forest, providing insights into the type of vegetation impacts that might be expected under predicted future drought.

Best fertilizer management practices such as adopting the right N sidedress timing can reduce N losses by volatilization, thus, raising N-fertilizer recovery and grain yield. To evaluate ammonia (N-NH3 ) losses, N-fertilizer recovery and grain yield as a function of urea sidedress timing in corn, a field study was conducted during the 2011-2012 and 2012-2013 growing seasons, adopting a complete randomized block design with four replications. Treatments consisted of urea sidedress timing (140 kg N ha-1) at V4, V6, V8, V10, and V12 growth stages, plus a control without sidedress N. The largest N losses by N-NH3 volatilization occurred when urea was applied at V10 or V12 growth stages, reaching losses of 35 and 41 % of the total applied N. Although climatic factors influences N-NH3 volatilization process, crop characteristics such as canopy development also seems to affect N-NH3 losses. Nitrogen application at V4 or V6 growth stages resulted in greater N-fertilizer recovery from urea sidedress, reaching values of 53 %. No increase in corn grain yield was observed with N application at different corn growth stages during the two growing seasons evaluated, most likely due to high N mineralization rates from the soil.

OBJECTIVE: The 13C-urea breath test is the main non-invasive test for the diagnosis of Helicobacter pylori infection. The availability of this test throughout the country is limited, mainly due to the difficulty in obtaining the labeled isotope from abroad. Recently, researchers from the Nuclear Energy Center in Agriculture at the University of São Paulo (CENA/USP) succeeded in synthesizing 13C-enriched urea for Helicobacter pylori diagnosis. The aim of the study was to compare the performance of the 13C-urea breath test using 13C-urea acquired abroad with that of a test using 13C-urea synthesized in Brazil. METHOD: Sixty-four dyspeptic patients participated in the study (24 men and 40 women). Initially, the patients performed the 13C-urea breath test using the imported substrate (Euriso-Top, France). Seven to fourteen days later, all the patients repeated the test using the Brazilian substrate. The samples from both examinations were processed in an infrared isotope analyzer (IRIS, Wagner Analisen Technik, Germany), and all delta over baseline (DOB) [%] values above four were considered positive results. RESULTS: Twenty-seven patients (42%) exhibited negative results for Helicobacter pylori infection, and thirty-seven patients (58%) exhibited positive results when tested using the foreign substrate (gold standard). There was a 100% concordance regarding the presence or absence of infection when the gold standard results were compared with those obtained using the Brazilian substrate. CONCLUSIONS: Similar performance in the diagnosis of Helicobacter pylori infection was demonstrated when using the 13C-urea breath test with the Brazilian 13C-urea substrate and the test with the substrate produced abroad. This validation represents an important step toward increasing the availability of the 13C-urea breath test throughout the country, which will have a positive influence on the management of Helicobacter pylori infection.

The aim of this paper is to reconstruct an 11,000-year history of depositional environmental change in southeastern Brazil, based upon the integration of particulate organic matter and stable isotope (C and N) data from a 136-cm sediment core from Lake Canto Grande. These proxies are used to explore the evolution of terrestrial and marine influence on the lake. Isotopic (δ13C: −27.87‰ to −31.9‰; δ15N: −0.07‰–4.9‰) and elemental (total organic carbon - TOC: 0.58%–37.19%; total nitrogen - TN: 0.08%–1.73%; C/N: 0.3 to 54.7) values recorded in Lake Canto Grande suggest that the sedimentary organic matter was derived from mostly C3 land plants and freshwater phytoplankton. Particulate organic matter and cluster analyses distinguished four associations characterized by the predominance of amorphous organic matter, followed by phytoclasts and palynomorphs. These results indicate two different phases of lake evolution. The first phase (136 - 65 cm; ∼10,943 cal yr. B.P. to ∼8529 cal yr. B.P.) is recorded by sand layers interbedded with mud, which contain amorphous organic matter (AOM, 45–59%) and phytoclasts (opaques - OP: 6–18%; non-opaques – NOP: 17–23%) which indicate a floodplain area. The second phase (65–0 cm; ∼8529 cal yr. B.P. to ∼662 cal yr. B.P.) comprises mud, AOM (68–86%) and palynomorphs (PAL, 8–16%) related to lake establishment comparable to modern conditions. Thus, characterizing particulate organic matter, in combination with stable isotopes, proved to be invaluable proxies for lacustrine paleoenvironmental change through the Holocene.

A truthful vegetation reconstruction is essential for understanding the historical trajectory of climate change and as well as the nature and extent of human impact on ecosystems. A classical approach to these studies is the use of pollen to identify flora composition and variability over time. However, the use of pollen is not always viable due to lack of depositional environments and general taphonomic processes, such as edaphic conditions. The most durable plant fossils, with widespread presence in diverse depositional realities, are phytoltihs. These proxies are common, well preserved in soils and with great potential for the detection of vegetation signals at micro and meso-level. Therefore, phytoliths are an important tool for recognising variability in major biomes such as tropical forests. In this study we illustrate the results of a pilot project in the Atlantic Forest (Mata Atlântica) of Brazil. The Atlantic Forest is a very diverse ecosystem and its environmental history is still poorly known, especially in relation to the origin and development of non-forested islands (campos nativos) within the forest. Campos nativos create a mosaic with the Mata Atlântica and their current persistence is due to a combination of topographic effects, hydrology and soil. Our work evaluated the potential of soil phytolith, total organic content (TOC) and δC of two grassland/savannah campos nativos in the Vale Nature Reserve in Linhares (state of Espírito Santo). The results from isotopic analysis show the relevance of C3 plants since the beginning, and for all the sedimentary history, in both campos nativos. The soils of the nativos are spodosols and, surprisingly, the phytolith composition has been drastically affected by the edaphic conditions. The phytolith assemblages are often impoverished, especially in the soil sandy layer. However, the assemblages still show an important local floristic component (micro scale) with an input from the surrounding vegetation (meso-scale)., We acknowledge the FAPESP funding (Projeto Temático 2011/00995-7 – ProjES) and CAPES funding (CAPES PVE A115/2013)

Particulate organic matter in sediments constitutes a valuable proxy for paleoenvironmental reconstructions. A 192 cm lacustrine sediment core (~ 7521 cal yr. B.P.) from the northern coast of the State of Espirito Santo, southeastern Brazil, was radiocarbon dated and then analyzed for palynofacies, stable isotopes (C and N), and grain size. The values for total organic carbon – TOC (1.91% to 20.89%), total nitrogen – TN (0.08% to 1.1%), δ13C (− 27.10‰ to − 29.01‰), δ15N (1.92‰ to 5.09‰) and C/N (12.87 to 50.11) suggest predominance of C3 plants and changing mixtures of terrestrial and aquatic organic matter in the sediments. Palynofacies and cluster analyses were used to identify four palynofacies associations that reflect different phases in the Lake Macuco evolution. Palynofacies 1 (192 to 106 cm, ~ 7521 cal yr. B.P. to ~ 7054 cal yr. B.P.—interpolated age) is characterized mainly by amorphous organic matter (AOM), non-opaque phytoclasts (NOPs), mangrove pollen grains (Rhizophora sp. L. 1753 and Avicennia sp. L. 1753), and foraminiferal test linings. Palynofacies 2 (106 to 65 cm, ~ 7054 cal yr. B.P.—interpolated age to ~ 4847 cal yr. B.P.) is dominated by NOPs and AOM, with an increase in the values of mangrove pollen grains relative to Palynofacies 1. Both palynofacies reflect marine and fluvial influences in a depositional environment related to the development of an estuarine system during the mid-Holocene transgressive stage. Palynofacies 3 (65 to 27 cm, ~ 4847 cal yr. B.P. to ~ 3800 cal yr. B.P.—interpolated age) comprises high abundances of fluvial elements (NOP and opaque phytoclasts—OP) and low values of AOM. The depositional environment is interpreted as being an estuary during the marine regression, with the displacement of the estuarine basin and mangroves towards the sea. Palynofacies 4 (27 to 0 cm, < ~ 3800 cal yr. B.P.) is characterized by the predominance of AOM and NOP, increase in the values of freshwater algae, and no evidence of marine influence. This last phase reflects the beginning of the establishment of Lake Macuco and floodplain of the Barra Seca River under conditions similar to the present-day.

A simple and straightforward approach to the diastereoselective synthesis of noncoded β-hydroxy-α-amino esters from Morita–Baylis–Hillman (MBH) adducts is described. The strategy is based on a one-pot sequence involving an oxidative cleavage of the double bond of silylated Morita–Baylis–Hillman adducts, followed by the reaction with hydroxylamine hydrochloride/pyridine to form oximes. The stereoselective reduction of the oximes with the mixture MoCl5·nH2O/NaBH3CN led to the corresponding anti-β-hydroxy-α-amino esters in four steps in good overall yield and with diastereoselectivity higher than 95%. A slight modification of the synthetic approach has allowed for the racemic synthesis of a set of noncoded α-amino esters/acids and DOPA.

The ion exchange chromatography technique in a cascade process was used to separate stable isotopes of nitrogen (14N/15N). For this purpose, three column systems (with different internal diameters, S1−14.5 cm; S2–9.5 cm; S3–5.2 cm) were used that contained the cationic resins DOWEX 50 WX8 (as H+ and equilibrated with H2O) and measured 1.7 m in height. Isotopic fractionation of nitrogen occurs during displacement band chromatography (DBC) of the NH3 (aq) solution with a 0.75 mol L−1 NaOH solution. The active sites of the resin were previously saturated to form NH4 + (RNH4) with a 0.75 mol L−1 solution of (NH4)2SO4 at a natural isotopic abundance (0.366 at. %) in 15N. The NH4 +/NH3 (aq) equilibrium was determined during the DBC, which enriched the rear portion of the band with 15N. In S1, enrichment of approximately 5 at. % of 15N in the last 10 cm was achieved. After four interactions (couplings) between S1–S2, an enrichment of approximately 50 at. % of 15N was obtained. During the interaction between S2–S...

Made available in DSpace on 2018-12-11T17:09:49Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-10-01. Added 1 bitstream(s) on 2019-10-09T18:30:49Z : No. of bitstreams: 1 S1516-635X2016000400719.pdf: 318730 bytes, checksum: 62e445b20f7c46f9332144629016cae6 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The objective of this study was to evaluate the process of L-methionine incorporation in the blood plasma, liver, breast muscle, and abdominal fat of 35- to 59-d-old broiler chickens using the carbon stable isotope (12C and 13C) technique for the estimation of methionine requirements. In this experiment, 51 male broiler chickens orally received a solution of L-[13C1] methionine (92 atm % 13C) at 29 µmol/kg live weight/h for 6 h. Three birds were sacrificed for tissue collection at times 0 h (control), 0.5, 1, 2, 3, 4, 5, 6, 12, 24, 48, 72, 96, 120, 144, 168, and 336 h after the administration of the first dose. Tissue L-[13C1] methionine incorporation mass and percentage results were analyzed using Minitab 16 statistical software. Except for abdominal fat, tissue methionine levels gradually increased after the administration of the methionine solution. The calculated half-lives of methionine in the blood plasma, liver, and breast muscle were 2.52, 1.36, and 3.57 h, respectively, suggesting a greater rate of methionine incorporation in the liver, followed by blood plasma and breast muscle. The isotopic dilution showed that 2.81, 4.79, and 23.64% of the administered L-methionine were retained in the blood plasma, liver, and breast muscle, respectively. The methionine requirements of finisher broilers may be estimated using the carbon isotope technique, and approximately 3, 5, and 24% methionine is used for the synthesis of blood plasma, liver, and breast muscle, respectively, at the evaluated dose. FMVZ/UNESP Center of Nuclear Energy in Agriculture CENA/USP Department of Physics and Biophysics IBB/UNESP Department of Genetic Improvement and Animal Nutrition FMVZ/UNESP FMVZ/UNESP Department of Physics and Biophysics IBB/UNESP Department of Genetic Improvement and Animal Nutrition FMVZ/UNESP FAPESP: 07/57776-0

A 190 cm mangrove sediment core from the Ilha do Cardoso State Park, State of Sao Paulo, southeastern Brazil was analyzed for pollen, diatoms as well as carbon and nitrogen isotopes. The goal was to determine the dynamics of the coastal terrestrial/aquatic ecosystems, vegetation history and climate change in this region of the Brazilian Atlantic rainforest, during the Late Pleistocene and Holocene. The values for total organic carbon—TOC (from ~ 3 up to 40%), C/N ratios (from ~ 10 up to 130), and δ15N (~ 0 to > 8) are associated with well preserved aquatic and terrestrial organic matter and possibly influenced by nitrogen cycling (e.g., denitrification) that caused 15N enrichment between > 40,000 cal yr B.P. and ~ 23,000 cal yr B.P. Depleted δ13C values (~ -28.0‰) are also observed and indicate the predominance of C3 plants. During this time interval, the pollen analysis reveals the presence of the genera Ilex, Alchornea, Weinmannia, Myrsine, Symplocos, Drimys and Podocarpus on a site currently occupied by mangrove vegetation. These data suggest that in the past prevailed a colder and more humid climate than today, with a low relative sea-level. From ~ 23,000 cal yr B.P. to ~ 2200 cal yr B.P. a sedimentary hiatus likely occurred, related to an erosive event associated to the post glacial sea-level rise. Since at least ~ 2200 cal yr B.P., sediments are marked by relatively low C/N ratios (from 2 to 27), exhibit more enriched δ13C (from ~-26.0‰ to − 24.0‰) and δ15N (up to ~ 7) values and are characterized by the presence of marine diatoms. This indicates the return of the marine coastal line to its current position, and consequently the development of mangrove.

This study aimed to evaluate minor and trace elements in the water during different water purification steps of a deionized water production plant, located at CENA, by total-reflection X-ray fluorescence (TXRF) technique, using Ga as internal standard for elemental quantification. This approach was capable of determining Cr, Mn, Fe, Co, Ni, Cu, Zn, Ge, As, Se, Br, Rb at concentrations higher than 40–100 μg L−1, and for K, Ca, Sc, Ti, V and Sr at concentrations higher than sub mg L−1 in the water samples. TXRF spectrometer encompasses an X-ray tube with a Mo target with a Zr filter. The elemental characteristic X-rays were recorded by a Si(Li) semiconductor detector and the X-ray spectra deconvoluted by AXIL software.