34 research outputs found
Cajanus cajan : a promissory high-nitrogen fixing cover crop for Uruguay
Cover crops can increase agricultural sustainability by protecting soil from
erosion, increasing biodiversity, and symbiotically incorporating fixed nitrogen
(N) into the soil. Nowadays, however, in Uruguay mostly grasses are planted in
autumn to protect the soil from erosion. Another option is to study tropical
legumes’ performance as cover crops, which can fix substantial amounts of
nitrogen in short growing periods, thereby bridging the knowledge gap in
Uruguayan agriculture. The main objective was to evaluate and compare the
performance of six tropical legumes (Crotalaria juncea, Crotalaria spectabilis,
Crotalaria ochroleuca, Cajanus cajan, Dolichos lablab, Mucuna pruriens) and the
temperate legume Glycine max. The evaluation focused on aboveground
biomass and the N mass derived from fixation (NmdFix), as well as other
attributes; three field experiments were conducted on a southern Uruguay
farm during the summers of 2017, 2018, and 2019. The growing cycle lengths
for the cover crops in 2017, 2018, and 2019 were 117, 130, and 90 days,
respectively. The results showed that when planting was done at late
December (2017 and 2018 growing cycles), the species with the highest mean
biomass yield were Crotalaria juncea (two year average 12.0 Mg ha⁻¹) and
Cajanus cajan (11.0 Mg ha⁻¹), but Cajanus cajan (149 kg ha⁻¹) more than
doubled the NmdFix mass of Crotalaria juncea (57 kg ha⁻¹). In 2018 biomass
yields were much higher than in 2017, with Glycine max (20.0 Mg ha⁻¹) yielding at
a similar level to Crotalaria juncea and Cajanus cajan (20.5 and 18.7 Mg ha⁻¹,
respectively). Amounts of NmdFix, however, were much higher in Glycine max
and Cajanus cajan (263 and 253 kg N ha⁻¹, respectively), than in Crotalaria juncea
(91 kg N ha⁻¹). In 2019 planting had to be delayed until early February and only
Glycine max maintained acceptable biomass and NmdFix levels. In conclusion,
based on its fixing N potential, for late December sowings Cajanus cajan and
Glycine max would be the most promising species for cover crop use, while for
late January or early February sowings, only Glycine max would an option
because the tropical species seriously impaired their productivity when grew
longer into the cooler autumn temperatures
Cajanus cajan: a promissory high-nitrogen fixing cover crop for Uruguay
Cover crops can increase agricultural sustainability by protecting soil from erosion, increasing biodiversity, and symbiotically incorporating fixed nitrogen (N) into the soil. Nowadays, however, in Uruguay mostly grasses are planted in autumn to protect the soil from erosion. Another option is to study tropical legumes’ performance as cover crops, which can fix substantial amounts of nitrogen in short growing periods, thereby bridging the knowledge gap in Uruguayan agriculture. The main objective was to evaluate and compare the performance of six tropical legumes (Crotalaria juncea, Crotalaria spectabilis, Crotalaria ochroleuca, Cajanus cajan, Dolichos lablab, Mucuna pruriens) and the temperate legume Glycine max. The evaluation focused on aboveground biomass and the N mass derived from fixation (NmdFix), as well as other attributes; three field experiments were conducted on a southern Uruguay farm during the summers of 2017, 2018, and 2019. The growing cycle lengths for the cover crops in 2017, 2018, and 2019 were 117, 130, and 90 days, respectively. The results showed that when planting was done at late December (2017 and 2018 growing cycles), the species with the highest mean biomass yield were Crotalaria juncea (two year average 12.0 Mg ha-1) and Cajanus cajan (11.0 Mg ha-1), but Cajanus cajan (149 kg ha-1) more than doubled the NmdFix mass of Crotalaria juncea (57 kg ha-1). In 2018 biomass yields were much higher than in 2017, with Glycine max (20.0 Mg ha-1) yielding at a similar level to Crotalaria juncea and Cajanus cajan (20.5 and 18.7 Mg ha-1, respectively). Amounts of NmdFix, however, were much higher in Glycine max and Cajanus cajan (263 and 253 kg N ha-1, respectively), than in Crotalaria juncea (91 kg N ha-1). In 2019 planting had to be delayed until early February and only Glycine max maintained acceptable biomass and NmdFix levels. In conclusion, based on its fixing N potential, for late December sowings Cajanus cajan and Glycine max would be the most promising species for cover crop use, while for late January or early February sowings, only Glycine max would an option because the tropical species seriously impaired their productivity when grew longer into the cooler autumn temperatures
T Cells Prevent Hemorrhagic Transformation in Ischemic Stroke by P-Selectin Binding
Objective Hemorrhagic transformation is a serious complication of ischemic stroke after recanalization therapies. This study aims to identify mechanisms underlying hemorrhagic transformation after cerebral ischemia/reperfusion. Approach and Results We used wild-type mice and Selplg(-/-) and Fut7(-/-) mice defective in P-selectin binding and lymphopenic Rag2(-/-) mice. We induced 30-minute or 45-minute ischemia by intraluminal occlusion of the middle cerebral artery and assessed hemorrhagic transformation at 48 hours with a hemorrhage grading score, histological means, brain hemoglobin content, or magnetic resonance imaging. We depleted platelets and adoptively transferred T cells of the different genotypes to lymphopenic mice. Interactions of T cells with platelets in blood were studied by flow cytometry and image stream technology. We show that platelet depletion increased the bleeding risk only after large infarcts. Lymphopenia predisposed to hemorrhagic transformation after severe stroke, and adoptive transfer of T cells prevented hemorrhagic transformation in lymphopenic mice. CD4(+) memory T cells were the subset of T cells binding P-selectin and platelets through functional P-selectin glycoprotein ligand-1. Mice defective in P-selectin binding had a higher hemorrhagic score than wild-type mice. Adoptive transfer of T cells defective in P-selectin binding into lymphopenic mice did not prevent hemorrhagic transformation. Conclusions The study identifies lymphopenia as a previously unrecognized risk factor for secondary hemorrhagic transformation in mice after severe ischemic stroke. T cells prevent hemorrhagic transformation by their capacity to bind platelets through P-selectin. The results highlight the role of T cells in bridging immunity and hemostasis in ischemic stroke
Impacto de la producción lechera en la calidad de los cuerpos de agua
La producción lechera es de las actividades de mayor desarrollo y más contaminantes en Uruguay. A efectos de evaluar y mitigar su impacto en la calidad del agua, se relacionan el modo de producción y de manejo de los efluentes lecheros con diversos indicadores de calidad de los arroyos receptores, en diez microcuencas de un embalse reserva de agua potable para Montevideo. Se analizó el agua subterránea en pozos, el contenido de fósforo del suelo, la calidad del ambiente y del agua de los cursos de salida de cada microcuenca, así como su comunidad zoobentónica, y también los parámetros ambientales y el fito- y zooplancton del embalse.La mayor parte de la producción lechera y de los habitantes se concentró en las seis cuencas más australes. Solo en la tercera parte de los 31 tambos se separaban los sólidos del estiércol y en la mitad se realizaba un tratamiento de los efluentes. El nitrato de los pozos de agua excedió el valor estándar en siete cuencas. El fósforo en campo natural superó los valores naturales en las microcuencas con mayor actividad lechera, y en las praderas excedió el máximo aprovechable y no contaminante. El pH y la conductividad de las aguas superficiales presentaron un patrón temporal inverso al caudal, indicando su dilución por la lluvia. Los sólidos suspendidos en cambio mostraron un patrón similar al caudal e inverso a la transparencia, indicando el arrastre de los mismos por erosión. La conductividad y los sólidos suspendidos fueron menores en cuencas con menor actividad lechera. Un quinto de los valores de oxígeno disuelto fueron menores a los 5 mg.l-1 correspondientes al estándar para aguas no urbanas. Los sólidos suspendidos y los nutrientes aumentaron con la actividad lechera. La vegetación herbácea dominó la zona riparia en general. La de las orillas fue más compleja y con mayor dosel aéreo en las cuencas con menor actividad lechera. La composición del zoobentos –dominado por Hyalella y Caenidae, indicadores de contaminación moderada-, mostró diferencias en relación al grado de impacto. Los arroyos con menor actividad lechera en sus cuencas mostraron la mayor diversidad. El embalse presentó una alta biodisponibilidad de nutrientes pero no un crecimiento excesivo del fitoplancton, cuya abundancia fue en general baja y no se registraron floraciones algales nocivas. La conductividad fue baja, el pH levemente alcalino y el oxígeno disuelto en general alto. La composición planctónica varió temporal y espacialmente, pero en general en la cola del embalse dominaron las diatomeas, en dos brazos receptores de cuencas lecheras y en la cabecera las cianobacterias y en otros dos brazos las euglenofitas y crisofitas. El zooplancton estuvo compuesto por rotíferos (45%), copépodos (36%), el molusco invasor Limnoperna fortunei (11%) y cladóceros (8%).Asociación de Universidades Grupo Montevide
Predictors of Survival After Head and Neck Squamous Cell Carcinoma in South America: The InterCHANGE Study.
PURPOSE: Head and neck squamous cell carcinoma (HNSCC) incidence is high in South America, where recent data on survival are sparse. We investigated the main predictors of HNSCC survival in Brazil, Argentina, Uruguay, and Colombia. METHODS: Sociodemographic and lifestyle information was obtained from standardized interviews, and clinicopathologic data were extracted from medical records and pathologic reports. The Kaplan-Meier method and Cox regression were used for statistical analyses. RESULTS: Of 1,463 patients, 378 had a larynx cancer (LC), 78 hypopharynx cancer (HC), 599 oral cavity cancer (OC), and 408 oropharynx cancer (OPC). Most patients (55.5%) were diagnosed with stage IV disease, ranging from 47.6% for LC to 70.8% for OPC. Three-year survival rates were 56.0% for LC, 54.7% for OC, 48.0% for OPC, and 37.8% for HC. In multivariable models, patients with stage IV disease had approximately 7.6 (LC/HC), 11.7 (OC), and 3.5 (OPC) times higher mortality than patients with stage I disease. Current and former drinkers with LC or HC had approximately 2 times higher mortality than never-drinkers. In addition, older age at diagnosis was independently associated with worse survival for all sites. In a subset analysis of 198 patients with OPC with available human papillomavirus (HPV) type 16 data, those with HPV-unrelated OPC had a significantly worse 3-year survival compared with those with HPV-related OPC (44.6% v 75.6%, respectively), corresponding to a 3.4 times higher mortality. CONCLUSION: Late stage at diagnosis was the strongest predictor of lower HNSCC survival. Early cancer detection and reduction of harmful alcohol use are fundamental to decrease the high burden of HNSCC in South America
Evaluación de matrices vítreas del sistema SiO2-Al2O3-CaO-MgO para fundentes aglomerados a través la basicidad óptica y criterios estructuro-químicos
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Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
The original version of this article unfortunately contained a mistake
Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study
Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
Differentiating pasture honey from eucalyptus honey based on carbon isotopic data in Uruguay
To avoid false declarations of geographic and botanical honey origin, traceability should be based on analytical data, which could then be processed by multivariate statistical methods. Obtaining this data, however, is costly and time consuming. Thus, it would be more convenient to acquire this information from routine trials, for example from the analysis for determination of high fructose corn syrup (HFCS) concentration in honey. The availability of a procedure of this kind in Uruguay would be useful in discriminating between honeys from grasslands to that from eucalyptus, the two main floral sources for commercial production. To this effect, honey samples (47 from pastures and 42 from eucalypts) were analyzed for δ13C in both honey and its protein fraction. We identified a logistic regression model that allowed us to correctly assign 90% of the training samples, using δ13C data of honey, protein fraction, and the isotopic index as variables. This model was then validated, obtaining 100% correct allocation for honeys from pasture and 90% for honeys from eucalyptus. Moreover, we found that this information could also be used to establish adulteration with HFCS based on a local stricter cut-off limit than that of -1.0‰ of the international index