A suitable alternative to replace fossil fuels is the production of bioethanol from agroindustrial waste. Grape pomace is the most abundant residue in San Juan and sugar beet pomace could be ...important in the region. Solid-State Fermentation (SSF) is a technology that allows transforming agroindustrial waste into many valuable bioproducts, like ethanol. This work reports a laboratory scale SSF to obtain alcohol from grape and sugar beet pomace by means of
Saccharomyces cerevisiae yeasts. The initial conditions of the culture medium were: sugars 16.5% (p/p); pH 4.5; humidity 68% (p/p). Cultures were inoculated with 10
8
cells/g of pomace, and incubated in anaerobic environment, at 28
°C, during 96
h. SSF showed ethanol maximum concentrations at 48
h and ethanol yield on sugars consumed was more than 82%. Yield attained creates expectation about the use of SSF to obtain fuel alcohol.
Trichinella
spp. from a sylvatic cycle has been found in several animal species such as pumas (
Puma concolor
), armadillos (
Chaetophractus villosus
), rats (
Rattus norvegicus
), and wild boars (
...Sus scrofa
) in Argentina. Moreover,
Trichinella
infection has been detected in a wide range of marine mammals around the world, including polar bears (
Ursus maritimus
) and walruses (
Odobenus rosmarus
). Until the present time,
Trichinella
spp. infection has not been detected in marine mammals of South America. Samples from four South American sea lions (
Otaria flavescens
) found dead in Rio Negro, Argentina, were analyzed by artificial digestion, and in the case of one animal,
Trichinella
larvae were identified at the species level by nested multiplex PCR as
Trichinella spiralis
. This is the first report of a
Trichinella
species infecting marine mammals from South America.
Due to its complex hydrological, geomorphological and climatic features, the Chilean fjords region is considered among the most productive areas of the world. The benthic fauna of this region ...accounts for more than 1600 species showing marked latitudinal biogeographic differences characterizing this as one of the most important hotspot of biodiversity of cold-temperate environments. Despite numerous studies have been conducted to depict the biological characteristics of the fjords, the present situation is strongly unbalanced towards specific taxa. Hence, this study takes into consideration a community approach, highlighting the distribution of six benthic assemblages thriving on vertical walls along the Seno Magdalena fjord (Aysen region). Underwater pictures were used to characterize the trends in abundance and diversity of the main taxa showing distinct responses to salinity and turbidity. Among the less tolerant taxa to high fresh water inputs there are encrusting algae, mainly found in the most external sites lashed by outer currents, far from the estuarine plume. The bathymetric zonation of the assemblages, instead, is characterized by a dense mussel belt in the first 10 m, within a thick layer of low-salinity, nutrient-enriched waters. Rich assemblages of sponges, brachiopods, gorgonians and scleractinians thrive in deeper, marine, clear waters. The evaluation of the ecological role of benthic species leads both to the definition of potential bioindicator taxa responding to anthropic disturbances and to the promotion of protected areas.
•This study couples passive and active acoustic time series data.•Our aim is to examine the drivers of blue whale presence over time.•Seasonal and submonthly blue whale presence was associated with ...euphausiid biomass.•Blue whale song calls followed a seasonal cycle; D-calls varied over submonthly cycles.•Spring tides may increase prey aggregation and/or transport into the Corcovado Gulf.•Short-lived storms may also contribute to the aggregation of prey.
Seasonal variation in the acoustic presence of blue whale calls has been widely reported for feeding grounds worldwide, however variation over the submonthly scale (several days to <1 month) has been examined to a much lesser extent. This study combines passive acoustic, hydroacoustic, and in situ oceanographic observations collected at a mooring in the Corcovado Gulf, Northern Chilean Patagonia, from January 2016-February 2017, to examine the temporal variation in blue whale acoustic occurrence and prey backscatter over seasonal and submonthly scales. Time series data for a) Southeast Pacific blue whale song calls and D-calls, b) zooplankton backscatter, c) tidal amplitude, and d) meridional and zonal wind stress were examined visually for seasonal trends. To examine submonthly timescales over the summer feeding season (January-June), wavelet transforms and wavelet coherence were applied; generalized linear models (GLM) were also applied. There was a 3-month lag between the seasonal onsets of high zooplankton backscatter (October) and blue whale acoustic presence (January), and an almost immediate drop in blue whale acoustic presence with the seasonal decrease of backscatter (June). This may be due to the use of memory by animals when timing their arrival on the feeding ground, but the timing of their departure may be related to detection of low prey availability. Over the summer feeding season, blue whale acoustic presence was strongly associated with zooplankton backscatter (GLM coefficient p ≪ 0.0001). Song calls followed a seasonal cycle, but D-calls appeared to respond to short term variations in environmental conditions over submonthly scales. Results suggest that spring tides may increase prey aggregation and/or transport into the Corcovado Gulf, leading to increased blue whale acoustic presence over 15-day or 30-day cycles; and short-lived events of increased wind stress with periodicities of 2–8 days and 16–30 days, may also contribute to the aggregation of prey. We discuss the strengths and limitations of coupling passive and active acoustic data to examine drivers of blue whale distribution.
Glaciated environments have been highlighted as important sources of bioavailable nutrients, with inputs of glacial meltwater potentially influencing productivity in downstream ecosystems. However, ...it is currently unclear how riverine nutrient concentrations vary across a spectrum of glacial cover, making it challenging to accurately predict how terrestrial fluxes will change with continued glacial retreat. Using 40 rivers in Chilean Patagonia as a unique natural laboratory, we investigate how glacial cover affects riverine Si and Fe concentrations, and infer how exports of these bioessential nutrients may change in the future. Dissolved Si (as silicic acid) and soluble Fe (<0.02 μm) concentrations were relatively low in glacier‐fed rivers, whereas concentrations of colloidal‐nanoparticulate (0.02–0.45 μm) Si and Fe increased significantly as a function of glacial cover. These colloidal‐nanoparticulate phases were predominately composed of aluminosilicates and Fe‐oxyhydroxides, highlighting the need for size‐fractionated analyses and further research to quantify the lability of colloidal‐nanoparticulate species. We also demonstrate the importance of reactive particulate (>0.45 μm) phases of both Si and Fe, which are not typically accounted for in terrestrial nutrient budgets but can dominate riverine exports. Dissolved Si and soluble Fe yield estimates showed no trend with glacial cover, suggesting no significant change in total exports with continued glacial retreat. However, yields of colloidal‐nanoparticulate and reactive sediment‐bound Si and Fe were an order of magnitude greater in highly glaciated catchments and showed significant positive correlations with glacial cover. As such, regional‐scale exports of these phases are likely to decrease as glacial cover disappears across Chilean Patagonia, with potential implications for downstream ecosystems.
Key Points
Si and Fe concentrations from 40 rivers in Chilean Patagonia reveal the impact of glacial cover on terrestrial nutrient cycling
Colloidal and reactive particulate phases of Si and Fe are elevated in glacier‐fed rivers and dominate export budgets
Riverine exports of Si and Fe are likely to significantly change with continued glacial retreat, which may impact productivity in downstream ecosystems
Biogeochemical processes in fjords are likely affected by changes in surrounding glacier cover but very little is known about how meltwater directly influences dissolved organic matter (DOM) in ...fjords. Moreover, the data available are restricted to a handful of northern hemisphere sites. Here we analyze seasonal and spatial variation in dissolved organic carbon (DOC) concentration and DOM composition (spectrofluorescence, ultrahigh resolution mass spectrometry) in Baker-Martinez Fjord, Chilean Patagonia (48°S), to infer the impacts of rapid regional deglaciation on fjord DOM. We show that surface layer DOC concentrations do not vary significantly between seasons, but DOM composition is sensitive to differences in riverine inputs. In summer, higher protein-like fluorescence reflects increased glacial meltwater inputs, whilst molecular level data show weaker influence from marine DOM due to more intense stratification. We postulate that the shifting seasonal balance of riverine and marine waters affects the supply of biolabile peptides and organic nitrogen cycling in the surface layer. Trends in DOM composition with increasing salinity are consistent with patterns in estuaries (i.e. preferential removal of aromatic compounds and increasing relative contribution of unsaturated and heteroatom-rich DOM from marine sources). Preliminary estimates also suggest that at least 10% of the annual organic carbon stock in this fjord is supplied by the four largest, glacially fed rivers and that these inputs are dominated by dissolved (84%) over particulate organic carbon. Riverine DOC may therefore be an important carbon subsidy to bacterial communities in the inner fjord. The overall findings highlight the biogeochemical sensitivity of a Patagonian fjord to changes in glacier melt input, which likely has relevance for other glaciated fjords in a warming climate.
Proglacial rivers have been shown to have distinctive silicon (Si) isotope compositions, providing new insights into the mechanisms controlling Si cycling in the subglacial environment and suggesting ...terrestrial Si isotope exports may have varied between glacial and interglacial periods. However, Si isotope data are currently limited to a small number of glacial systems in the northern hemisphere, and it is unclear how compositions might vary across a spectrum of glacial influence. Using Chilean Patagonia as a unique natural laboratory, we present Si isotope compositions of 0.45 μm filtered (fSi), 0.02 μm filtered (DSi), and reactive amorphous (ASi) fractions from 40 river catchments with variable glacial cover and explore the key controls on Si cycling. The 0.45 μm filtered glacier-fed river samples displayed isotopically light compositions and a positive linear correlation with upstream glacial cover. This relationship was controlled by the inclusion of an isotopically light colloidal-nanoparticulate (0.02–0.45 μm) silicate phase that was only present in glacier-fed rivers and dominated Si budgets in these catchments. This phase was predominately composed of feldspars and its lability in seawater is uncertain, representing a significant unknown in resolving glacial Si isotope exports from this region. When the colloidal-nanoparticulates were removed from solution by ultra-filtration, the resultant DSi isotope compositions of glacier-fed catchments were not isotopically distinct from some non-glacial rivers and exhibited no clear relationship with glacial cover. The colloidal-nanoparticulate concentration of other weathering-sensitive elements (Li, Mg, Ba, Sr) also showed a linear relationship with glacial cover, suggesting that their isotopic compositions could be affected in a similar manner. These findings highlight the benefit of size-fractionated sampling and the need for more research to understand the lability of colloidal-nanoparticulate species, especially in glacier-fed rivers. Finally, we explore the controls on river ASi isotope compositions and show how including these reactive particulate phases is critical to quantifying terrestrial Si isotope budgets, both in Patagonia and other global regions.
OBJECTIVERheumatoid Arthritis (RA) is an autoimmune and chronic inflammatory disease of unknown etiology. Killer cell immunoglobulin-like receptors are expressed on the surface of natural killer ...cells and CD28null T-cells, both present in synovial membrane of RA. Therefore we evaluated the associations of KIR genes with RA. METHODS16 KIR genes were genotyped in 100 healthy subjects (HS) and 100 RA patients from Western Mexico using PCR-SSP. Differences in KIR genotypes and gene frequencies were assessed using the X^{2} test. RESULTSGene frequency of KIR2DL3 was lower in RA than in HS (p= 0.0019), whereas KIR2DL2 and KIR2DS2 were higher in RA than HS (p =0.0004 and p = 0.0487, respectively). In addition were identified 38 genotypes (from G1-G38) in both studied groups, and the genotype frequencies of G1, G6 and G14 showed significant differences (p =0.0001, p =0.0208 and p =0.0300, respectively). CONCLUSIONSThe presence of KIR2DL2, KIR2DS2 and absence of KIR2DL3 are associated with RA. Moreover, two genotypes BX are associated with RA. These results suggest that KIRs can be involved in RA susceptibility.
The transtheoretical model (TTM) has been widely used to promote healthy behaviors in different groups. However, a questionnaire has not yet been developed to evaluate the health behaviors that ...medical practitioners often consider in individuals with cancer or at a high risk of developing cancer.
The aim of this study was to construct and validate the Health Behavior and Stages of Change Questionnaire (HBSCQ), which is based on the TTM and health recommendations related to risk and factors that protect against cancer.
Content validity was conducted in two phases (qualitative and quantitative). Item difficulty index, item discrimination index, and discrimination coefficient were obtained based on the classical test theory. Finally, Cronbach's alpha was used.
Measure of concordance showed scores considered adequate and excellent. The item discrimination index obtained a rating of "excellent" and suggested the preservation of all items. The discrimination coefficient scores are >0.74. The global internal consistency of the HBSCQ was 0.384. HBSCQ specification between groups of internal consistency for the sample of men was 0.712 and that for the sample of women was 0.378.
The HBSCQ represents a proposal for a fast, simple, and innovative screening test, which aims to identify persons who may benefit from interventions to promote health behaviors delimited to the stage of change.
Rheumatoid Arthritis (RA) is an autoimmune and chronic inflammatory disease of unknown etiology. Killer cell immunoglobulin-like receptors are expressed on the surface of natural killer cells and ...CD28null T-cells, both present in synovial membrane of RA. Therefore we evaluated the associations of KIR genes with RA.
16 KIR genes were genotyped in 100 healthy subjects (HS) and 100 RA patients from Western Mexico using PCR-SSP. Differences in KIR genotypes and gene frequencies were assessed using the X^{2} test.
Gene frequency of KIR2DL3 was lower in RA than in HS (p= 0.0019), whereas KIR2DL2 and KIR2DS2 were higher in RA than HS (p =0.0004 and p = 0.0487, respectively). In addition were identified 38 genotypes (from G1-G38) in both studied groups, and the genotype frequencies of G1, G6 and G14 showed significant differences (p =0.0001, p =0.0208 and p =0.0300, respectively).
The presence of KIR2DL2, KIR2DS2 and absence of KIR2DL3 are associated with RA. Moreover, two genotypes BX are associated with RA. These results suggest that KIRs can be involved in RA susceptibility.
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