45 research outputs found
Impact of Increased Nutrients and Lowered pH on Photosynthesis and Growth of Three Marine Phytoplankton Communities From the Coastal South West Atlantic (Patagonia, Argentina)
Effect of global change variables on the structure and photosynthesis of phytoplankton communities was evaluated in three different sites of the Patagonian coast of Argentina: enclosed bay (Puerto Madryn, PM), estuarine (Playa Unión, PU), and open waters (Isla Escondida, IE). We exposed samples to two contrasting scenarios: Present (nutrients at in situ levels) vs. Future (with lowered pH and higher nutrients inputs), and determined growth and photosynthetic responses after 2 days of acclimation. Under the Future condition phytoplankton growth was higher in the estuarine site compared to those in PM and IE. This effect was the most pronounced on large diatoms. While the increase of photosynthetic activity was not always observed in the Future scenario, the lower photosynthetic electron requirement for carbon fixation (Φe,C = ETR/PmB) in this scenario compared to the Present, suggests a more effective energy utilization. Long-term experiments were also conducted to assess the responses along a 4 days acclimation period in PU. Diatoms benefited from the Future conditions and had significantly higher growth rates than in the Present. In addition, Φe,C was lower after the acclimation period in the Future scenario, compared to the Present. Our results suggest that the availability, frequency and amount of nutrients play a key role when evaluating the effects of global change on natural phytoplankton communities. The observed changes in diatom growth under the Future scenario in PU and IE and photosynthesis may have implications in the local trophodynamics by bottom up control
Multiple interacting environmental drivers reduce the impact of solar UVR on primary productivity in Mediterranean lakes
Increases in rainfall, continental runoff, and atmospheric dust deposition are reducing water transparency in lakes worldwide (i.e. higher attenuation Kd). Also, ongoing alterations in multiple environmental drivers due to global change are unpredictably impacting phytoplankton responses and lakes functioning. Although both issues demand urgent research, it remains untested how the interplay between Kd and multiple interacting drivers affect primary productivity (Pc). We manipulated four environmental drivers in an in situ experiment—quality of solar ultraviolet radiation (UVR), nutrient concentration (Nut), CO2 partial pressure (CO2), and light regime (Mix)—to determine how the Pc of nine freshwater phytoplankton communities, found along a Kd gradient in Mediterranean ecosystems, changed as the number of interacting drivers increased. Our findings indicated that UVR was the dominant driver, its effect being between 3–60 times stronger, on average, than that of any other driver tested. Also, UVR had the largest difference in driver magnitude of all the treatments tested. A future UVR × CO2 × Mix × Nut scenario exerted a more inhibitory effect on Pc as the water column became darker. However, the magnitude of this synergistic effect was 40–60% lower than that exerted by double and triple interactions and by UVR acting independently. These results illustrate that although future global-change conditions could reduce Pc in Mediterranean lakes, multiple interacting drivers can temper the impact of a severely detrimental driver (i.e. UVR), particularly as the water column darkensMinisterio de Ciencia, Innovación y Universidades | Ref. FJCI2017-32318Ministerio de Economía y Competitividad | Ref. CGL2015-67682-RMinisterio de Economía y Competitividad | Ref. CGL2011-23681Ministerio de Medio Ambiente y Medio Rural y Marino | Ref. PN2009/067Junta de Andalucía | Ref. P09-RNM-5376Junta de Andalucía | Ref. Excelencia CVI-0259
Multiple interacting environmental drivers reduce the impact of solar UVR on primary productivity in Mediterranean lakes
Increases in rainfall, continental runoff, and atmospheric dust deposition are reducing water
transparency in lakes worldwide (i.e. higher attenuation Kd). Also, ongoing alterations in multiple
environmental drivers due to global change are unpredictably impacting phytoplankton responses
and lakes functioning. Although both issues demand urgent research, it remains untested how the
interplay between Kd and multiple interacting drivers affect primary productivity (
Pc). We manipulated
four environmental drivers in an in situ experiment—quality of solar ultraviolet radiation (UVR),
nutrient concentration (Nut), CO2
partial pressure (
CO2), and light regime (Mix)—to determine how
the Pc
of nine freshwater phytoplankton communities, found along a Kd gradient in Mediterranean
ecosystems, changed as the number of interacting drivers increased. Our findings indicated that UVR
was the dominant driver, its effect being between 3–60 times stronger, on average, than that of any
other driver tested. Also, UVR had the largest difference in driver magnitude of all the treatments
tested. A future UVR × CO2 × Mix × Nut scenario exerted a more inhibitory effect on Pc
as the water
column became darker. However, the magnitude of this synergistic effect was 40–60% lower than that
exerted by double and triple interactions and by UVR acting independently. These results illustrate
that although future global-change conditions could reduce Pc
in Mediterranean lakes, multiple
interacting drivers can temper the impact of a severely detrimental driver (i.e. UVR), particularly as the
water column darkens.Ministerio de Economía y Competividad (MINECO)European Union (EU)
MICROSENSCGL2011-23681
METAS-CGL2015-67682-RMedio Ambiente, Rural, y Marino
PN2009/067Junta de Andalucía
CVI-02598
P09-RNM-5376Fundación Playa Unión (Argentina)Juan de la Cierva-Formacion from the Ministerio de Ciencia, Innovación y Universidades
FJCI2017-32318Postdoctoral contract "Contrato Puente" from Plan Propio (FP7/2017) of the University of GranadaMETAS projec
Ocean Acidification Alters the Photosynthetic Responses of a Coccolithophorid to Fluctuating Ultraviolet and Visible Radiation
Menstrual and Reproductive Factors and Risk of Gastric and Colorectal Cancer in Spain
BACKGROUND:
Sex hormones play a role in gastric cancer and colorectal cancer etiology, however, epidemiological evidence is inconsistent. This study examines the influence of menstrual and reproductive factors over the risk of both tumors.
METHODS:
In this case-control study 128 women with gastric cancer and 1293 controls, as well as 562 female and colorectal cancer cases and 1605 controls were recruited in 9 and 11 Spanish provinces, respectively. Population controls were frequency matched to cases by age and province. Demographic and reproductive data were directly surveyed by trained staff. The association with gastric, colon and rectal cancer was assessed using logistic and multinomial mixed regression models.
RESULTS:
Our results show an inverse association of age at first birth with gastric cancer risk (five-year trend: OR = 0.69; p-value = 0.006). Ever users of hormonal contraception presented a decreased risk of gastric (OR = 0.42; 95%CI = 0.26-0.69), colon (OR = 0.64; 95%CI = 0.48-0.86) and rectal cancer (OR = 0.61; 95%CI = 0.43-0.88). Postmenopausal women who used hormone replacement therapy showed a decreased risk of colon and rectal tumors. A significant interaction of educational level with parity and months of first child lactation was also observed.
CONCLUSION:
These findings suggest a protective role of exogenous hormones in gastric and colorectal cancer risk. The role of endogenous hormones remains unclear
El Derecho Argentino frente a la pandemia y post-pandemia COVID-19. TOMO I
La Facultad de Derecho de la Universidad Nacional de Córdoba no
podía permanecer indolente frente a la conmoción que, durante este año
2020, ha provocado en el mundo la pandemia de COVID-19.
Como comunidad educativa advertíamos que la prioridad máxima era
lograr la continuidad de la labor de nuestra Casa de Estudios, para garantizar a nuestros alumnos del grado y del posgrado, el ejercicio de su derecho
a estudiar, continuando y en algunos casos iniciando sus estudios, a pesar
de las condiciones adversas que se vivían. Con esa finalidad convocamos a los profesores titulares de todas las
cátedras y eméritos y consultos que quisieran hacerlo, a sumarse con sus
aportes a esta construcción colectiva, que aborda los temas que nos ocupan
desde las diversas perspectivas de las distintas áreas del mundo jurídico. Y la desinteresada respuesta positiva no se hizo esperar. Prueba de ello es este
libro cuyas dimensiones, tanto en lo cuantitativo como en lo cualitativo,
superaron las expectativas iniciales. La jerarquía de los autores que generosamente han participado con sus
contribuciones, en algunos casos en forma individual y en otros acompañados por sus equipos de colaboradores, permiten prever que esta obra ha de
brindar elementos de juicio de gran utilidad para continuar construyendo el
mundo jurídico, dentro de la pandemia y después de ella.ÍNDICE GENERAL. TOMO I. "Pandemia, postpandemia y derecho" por Guillermo Eduardo Barrera Buteler. UNIVERSIDAD Y PANDEMIA: "Desafíos y estrategias de la Universidad Nacional de Córdoba en tiempos de COVID-19. Enseñanza y aprendizaje pospandemia" por Ramón Pedro Yanzi Ferreira. HISTORIA. HISTORIA DEL DERECHO. DERECHO ROMANO: "De las pestes en la antigua Roma" por Edgardo García Chiple, Juan B. Fernández, Marisa Domínguez y Laura Salomón. Adscriptos: Carla Pedrón, Julieta Dalin, Lorena Sánchez, Eduardo Villafañe Molina y Rodrigo López. "Los cuerpos heridos. Las epidemias en la historia" por Marcela Aspell. DERECHO PRIVADO: "Los principios generales del Derecho Privado como instrumentos de solución de conflictos derivados de la pandemia del coronavirus" por Juan Carlos Palmero. "COVID-19 y contrato" por Juan Manuel Aparicio. "Saliendo de la crisis (Una mirada a la preconcursalidad privada para la actividad empresarial: nada nuevo, solo ideas o actitudes nuevas)" por Efraín Hugo Richard. "Responsabilidad de administradores en la emergencia" por Horacio Roitman, Alejandro Vergara, Marcos Broglio Michelli y María Victoria Marengo. "Alteración de las circunstancias por efecto de la pandemia de Covid 19 y exigibilidad contractual" por Alejandro E. Freytes. "Daños causados por contagio por coronavirus. La cuestión de la causalidad" por José Fernando Márquez. "El ejercicio de los derechos personalísimos en tiempos de pandemia y post pandemia" por Beatriz Junyent de Sandoval, Patricia Stein y Gabriel Eugenio Tavip. "Panorama sobre la normativa de emergencia COVID-19 en la publicidad registral de los derechos reales sobre inmuebles provincia de Córdoba" por Raquel Virginia Moyano y Gabriela Sosa.Fil: Barrera Buteler, Guillermo Eduardo. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Yanzi Ferreira, Ramón Pedro. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: García Chiple, Edgardo. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Fernández, Juan B. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Domínguez, Marisa. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Salomón, Laura. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Pedrón, Carla. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Dalin, Julieta. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Sánchez, Lorena. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Villafañe Molina, Eduardo. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: López, Rodrigo. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Aspell, Marcela. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Palmero, Juan Carlos. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Aparicio, Juan Manuel. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Richard, Efraín Hugo. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Roitman, Horacio. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Vergara, Alejandro. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Broglio Michelli, Marcos. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Marengo, María Victoria. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Freytes, Alejandro E. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Márquez, José Fernando. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Junyent de Sandoval, Beatriz. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Stein, Patricia. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Tavip, Gabriel Eugenio. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Moyano, Raquel Virginia. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina.Fil: Sosa, Gabriela. Universidad Nacional de Córdoba. Facultad de Derecho; Argentina
Mapping age- and sex-specific HIV prevalence in adults in sub-Saharan Africa, 2000–2018
Background: Human immunodeficiency virus and acquired immune deficiency syndrome (HIV/AIDS) is still among the leading causes of disease burden and mortality in sub-Saharan Africa (SSA), and the world is not on track to meet targets set for ending the epidemic by the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the United Nations Sustainable Development Goals (SDGs). Precise HIV burden information is critical for effective geographic and epidemiological targeting of prevention and treatment interventions. Age- and sex-specific HIV prevalence estimates are widely available at the national level, and region-wide local estimates were recently published for adults overall. We add further dimensionality to previous analyses by estimating HIV prevalence at local scales, stratified into sex-specific 5-year age groups for adults ages 15–59 years across SSA. Methods: We analyzed data from 91 seroprevalence surveys and sentinel surveillance among antenatal care clinic (ANC) attendees using model-based geostatistical methods to produce estimates of HIV prevalence across 43 countries in SSA, from years 2000 to 2018, at a 5 × 5-km resolution and presented among second administrative level (typically districts or counties) units. Results: We found substantial variation in HIV prevalence across localities, ages, and sexes that have been masked in earlier analyses. Within-country variation in prevalence in 2018 was a median 3.5 times greater across ages and sexes, compared to for all adults combined. We note large within-district prevalence differences between age groups: for men, 50% of districts displayed at least a 14-fold difference between age groups with the highest and lowest prevalence, and at least a 9-fold difference for women. Prevalence trends also varied over time; between 2000 and 2018, 70% of all districts saw a reduction in prevalence greater than five percentage points in at least one sex and age group. Meanwhile, over 30% of all districts saw at least a five percentage point prevalence increase in one or more sex and age group. Conclusions: As the HIV epidemic persists and evolves in SSA, geographic and demographic shifts in prevention and treatment efforts are necessary. These estimates offer epidemiologically informative detail to better guide more targeted interventions, vital for combating HIV in SSA
Mapping age- and sex-specific HIV prevalence in adults in sub-Saharan Africa, 2000-2018
BACKGROUND: Human immunodeficiency virus and acquired immune deficiency syndrome (HIV/AIDS) is still among the leading causes of disease burden and mortality in sub-Saharan Africa (SSA), and the world is not on track to meet targets set for ending the epidemic by the Joint United Nations Programme on HIV/AIDS (UNAIDS) and the United Nations Sustainable Development Goals (SDGs). Precise HIV burden information is critical for effective geographic and epidemiological targeting of prevention and treatment interventions. Age- and sex-specific HIV prevalence estimates are widely available at the national level, and region-wide local estimates were recently published for adults overall. We add further dimensionality to previous analyses by estimating HIV prevalence at local scales, stratified into sex-specific 5-year age groups for adults ages 15-59 years across SSA. METHODS: We analyzed data from 91 seroprevalence surveys and sentinel surveillance among antenatal care clinic (ANC) attendees using model-based geostatistical methods to produce estimates of HIV prevalence across 43 countries in SSA, from years 2000 to 2018, at a 5 × 5-km resolution and presented among second administrative level (typically districts or counties) units. RESULTS: We found substantial variation in HIV prevalence across localities, ages, and sexes that have been masked in earlier analyses. Within-country variation in prevalence in 2018 was a median 3.5 times greater across ages and sexes, compared to for all adults combined. We note large within-district prevalence differences between age groups: for men, 50% of districts displayed at least a 14-fold difference between age groups with the highest and lowest prevalence, and at least a 9-fold difference for women. Prevalence trends also varied over time; between 2000 and 2018, 70% of all districts saw a reduction in prevalence greater than five percentage points in at least one sex and age group. Meanwhile, over 30% of all districts saw at least a five percentage point prevalence increase in one or more sex and age group. CONCLUSIONS: As the HIV epidemic persists and evolves in SSA, geographic and demographic shifts in prevention and treatment efforts are necessary. These estimates offer epidemiologically informative detail to better guide more targeted interventions, vital for combating HIV in SSA
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation