298 research outputs found

    Avaliação de alternativas aos revestimentos com alcatrão de hulha para estruturas de aço total ou parcialmente imersas em estuário e água do mar

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    Na procura de revestimentos anticorrosivos para protecção de estruturas de aço total ou parcialmente imersas em estuário e água do mar, que sejam alternativas mais ecológicas aos revestimentos com alcatrão de hulha ainda utilizados, foi desenvolvido um projecto no qual se comparam revestimentos epoxídicos comerciais com um revestimento de alcatrão de hulha epoxídico de referência, também comercial. Este trabalho inclui, para além da avaliação da protecção anticorrosiva dos revestimentos envolvidos no projecto, quer em laboratório, quer em exposição natural em estuário (rios Sado e Tejo) e em mar (Sines) durante quatro anos, a caracterização laboratorial das tintas integradas nos diferentes esquemas de pintura que deram origem aos revestimentos em estudo. Os resultados da avaliação no fim de dois anos de exposição natural, complementados com os ensaios em laborató permitiram concluir que dois dos quatro revestimentos alternativos estudados apresentaram melhor comportamento anticorrosivo do que o revestimento com alcatrão de hulha epoxídico usado como referência

    Diretriz Brasileira sobre a Saúde Cardiovascular no Climatério e na Menopausa – 2024

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    Women, who represent approximately half of the global population according to estimates as of January 2024, may experience signs and symptoms of menopause for at least one-third of their lives, during which they have a higher risk of cardiovascular morbidity and mortality. The effects of menopausal hormone therapy (MHT) on the progression of atherosclerosis and cardiovascular disease (CVD) events vary depending on the age at which MHT is initiated and the time since menopause until its initiation. Beneficial effects on CVD outcomes and all-cause mortality have been observed when MHT was initiated before the age of 60 or within 10 years after menopause. The decision regarding the initiation, dose, regimen, and duration of MHT should be made individually after discussing the benefits and risks with each patient. For primary prevention of postmenopausal chronic conditions, the combined use of estrogen and progestogen is not recommended in asymptomatic women, nor is the use of estrogen alone in hysterectomized women. Hormone-dependent neoplasms contraindicate MHT. For the treatment of genitourinary syndrome of menopause, vaginal estrogen therapy may be used in patients with known cardiovascular risk factors or established CVD. For women with contraindications to MHT or who refuse it, non-hormonal therapies with proven efficacy (antidepressants, gabapentin, and fezolinetant) may improve vasomotor symptoms. Compounded hormonal implants, or "bioidentical" and "compounded" hormones, and "hormone modulation" are not recommended due to lack of scientific evidence of their effectiveness and safety.Mujeres, que representan aproximadamente la mitad de la población mundial según estimaciones de enero de 2024, pueden experimentar signos y síntomas de la menopausia durante al menos un tercio de sus vidas, durante los cuales tienen un mayor riesgo de morbilidad y mortalidad cardiovascular. Los efectos de la terapia hormonal de la menopausia (THM) en la progresión de la aterosclerosis y los eventos de enfermedad cardiovascular (ECV) varían según la edad en que se inicia la THM y el tiempo transcurrido desde la menopausia hasta su inicio. Se han observado efectos beneficiosos en los resultados de ECV y la mortalidad por todas las causas cuando la THM se inició antes de los 60 años o dentro de los 10 años posteriores a la menopausia. La decisión sobre la iniciación, dosis, régimen y duración de la THM debe tomarse individualmente después de discutir los beneficios y riesgos con cada paciente. Para la prevención primaria de condiciones crónicas en la posmenopausia, no se recomienda el uso combinado de estrógeno y progestágeno en mujeres asintomáticas, ni el uso de estrógeno solo en mujeres histerectomizadas. Las neoplasias dependientes de hormonas contraindican la THM. Para el tratamiento del síndrome genitourinario de la menopausia, se puede usar terapia estrogénica vaginal en pacientes con factores de riesgo cardiovascular conocidos o ECV establecida. Para mujeres con contraindicaciones a la THM o que la rechazan, las terapias no hormonales con eficacia demostrada (antidepresivos, gabapentina y fezolinetant) pueden mejorar los síntomas vasomotores. Los implantes hormonales compuestos, o hormonas "bioidénticas" y "compuestas", y la "modulación hormonal" no se recomiendan debido a la falta de evidencia científica sobre su efectividad y seguridad.As mulheres, que representam cerca de metade da população mundial segundo estimativas de janeiro de 2024, podem sofrer com sinais e sintomas da menopausa durante pelo menos um terço de suas vidas, quando apresentam maiores risco e morbimortalidade cardiovasculares. Os efeitos da terapia hormonal da menopausa (THM) na progressão de eventos de aterosclerose e doença cardiovascular (DCV) variam de acordo com a idade em que a THM é iniciada e o tempo desde a menopausa até esse início. Efeitos benéficos nos resultados de DCV e na mortalidade por todas as causas ocorreram quando a THM foi iniciada antes dos 60 anos de idade ou nos 10 anos que se seguiram à menopausa. A decisão sobre o início, a dose, o regime e a duração da THM deve ser tomada individualmente após discussão sobre benefícios e riscos com cada paciente. Para a prevenção primária de condições crônicas na pós-menopausa, não se recomendam o uso combinado de estrogênio e progestagênio em mulheres assintomáticas nem o uso de estrogênio sozinho em mulheres histerectomizadas. Neoplasias hormônio-dependentes contraindicam a THM. Para tratamento da síndrome geniturinária da menopausa, pode-se utilizar terapia estrogênica por via vaginal em pacientes com fatores de risco cardiovascular conhecidos ou DCV estabelecida. Para mulheres com contraindicação à THM ou que a recusam, terapias não hormonais com eficácia comprovada (antidepressivos, gabapentina e fezolinetante) podem melhorar os sintomas vasomotores. Os implantes hormonais manipulados, ou hormônios “bioidênticos” “manipulados”, e a ‘modulação hormonal’ não são recomendados pela falta de evidência científica de sua eficácia e segurança

    Convalescent plasma for COVID-19 in hospitalised patients : an open-label, randomised clinical trial

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    Background: The effects of convalescent plasma (CP) therapy in hospitalised patients with coronavirus disease 2019 (COVID-19) remain uncertain. This study investigates the effect of CP on clinical improvement in these patients. Methods: This is an investigator-initiated, randomised, parallel arm, open-label, superiority clinical trial. Patients were randomly (1:1) assigned to two infusions of CP plus standard of care (SOC) or SOC alone. The primary outcome was the proportion of patients with clinical improvement 28 days after enrolment. Results: A total of 160 (80 in each arm) patients (66.3% critically ill, 33.7% severely ill) completed the trial. The median (interquartile range (IQR)) age was 60.5 (48–68) years; 58.1% were male and the median (IQR) time from symptom onset to randomisation was 10 (8–12) days. Neutralising antibody titres >1:80 were present in 133 (83.1%) patients at baseline. The proportion of patients with clinical improvement on day 28 was 61.3% in the CP+SOC group and 65.0% in the SOC group (difference −3.7%, 95% CI −18.8–11.3%). The results were similar in the severe and critically ill subgroups. There was no significant difference between CP+SOC and SOC groups in pre-specified secondary outcomes, including 28-day mortality, days alive and free of respiratory support and duration of invasive ventilatory support. Inflammatory and other laboratory marker values on days 3, 7 and 14 were similar between groups. Conclusions: CP+SOC did not result in a higher proportion of clinical improvement on day 28 in hospitalised patients with COVID-19 compared to SOC alone

    MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

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    Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Estimating the global conservation status of more than 15,000 Amazonian tree species

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    Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict thatmost of the world’s >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century

    State of the climate in 2018

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    In 2018, the dominant greenhouse gases released into Earth’s atmosphere—carbon dioxide, methane, and nitrous oxide—continued their increase. The annual global average carbon dioxide concentration at Earth’s surface was 407.4 ± 0.1 ppm, the highest in the modern instrumental record and in ice core records dating back 800 000 years. Combined, greenhouse gases and several halogenated gases contribute just over 3 W m−2 to radiative forcing and represent a nearly 43% increase since 1990. Carbon dioxide is responsible for about 65% of this radiative forcing. With a weak La Niña in early 2018 transitioning to a weak El Niño by the year’s end, the global surface (land and ocean) temperature was the fourth highest on record, with only 2015 through 2017 being warmer. Several European countries reported record high annual temperatures. There were also more high, and fewer low, temperature extremes than in nearly all of the 68-year extremes record. Madagascar recorded a record daily temperature of 40.5°C in Morondava in March, while South Korea set its record high of 41.0°C in August in Hongcheon. Nawabshah, Pakistan, recorded its highest temperature of 50.2°C, which may be a new daily world record for April. Globally, the annual lower troposphere temperature was third to seventh highest, depending on the dataset analyzed. The lower stratospheric temperature was approximately fifth lowest. The 2018 Arctic land surface temperature was 1.2°C above the 1981–2010 average, tying for third highest in the 118-year record, following 2016 and 2017. June’s Arctic snow cover extent was almost half of what it was 35 years ago. Across Greenland, however, regional summer temperatures were generally below or near average. Additionally, a satellite survey of 47 glaciers in Greenland indicated a net increase in area for the first time since records began in 1999. Increasing permafrost temperatures were reported at most observation sites in the Arctic, with the overall increase of 0.1°–0.2°C between 2017 and 2018 being comparable to the highest rate of warming ever observed in the region. On 17 March, Arctic sea ice extent marked the second smallest annual maximum in the 38-year record, larger than only 2017. The minimum extent in 2018 was reached on 19 September and again on 23 September, tying 2008 and 2010 for the sixth lowest extent on record. The 23 September date tied 1997 as the latest sea ice minimum date on record. First-year ice now dominates the ice cover, comprising 77% of the March 2018 ice pack compared to 55% during the 1980s. Because thinner, younger ice is more vulnerable to melting out in summer, this shift in sea ice age has contributed to the decreasing trend in minimum ice extent. Regionally, Bering Sea ice extent was at record lows for almost the entire 2017/18 ice season. For the Antarctic continent as a whole, 2018 was warmer than average. On the highest points of the Antarctic Plateau, the automatic weather station Relay (74°S) broke or tied six monthly temperature records throughout the year, with August breaking its record by nearly 8°C. However, cool conditions in the western Bellingshausen Sea and Amundsen Sea sector contributed to a low melt season overall for 2017/18. High SSTs contributed to low summer sea ice extent in the Ross and Weddell Seas in 2018, underpinning the second lowest Antarctic summer minimum sea ice extent on record. Despite conducive conditions for its formation, the ozone hole at its maximum extent in September was near the 2000–18 mean, likely due to an ongoing slow decline in stratospheric chlorine monoxide concentration. Across the oceans, globally averaged SST decreased slightly since the record El Niño year of 2016 but was still far above the climatological mean. On average, SST is increasing at a rate of 0.10° ± 0.01°C decade−1 since 1950. The warming appeared largest in the tropical Indian Ocean and smallest in the North Pacific. The deeper ocean continues to warm year after year. For the seventh consecutive year, global annual mean sea level became the highest in the 26-year record, rising to 81 mm above the 1993 average. As anticipated in a warming climate, the hydrological cycle over the ocean is accelerating: dry regions are becoming drier and wet regions rainier. Closer to the equator, 95 named tropical storms were observed during 2018, well above the 1981–2010 average of 82. Eleven tropical cyclones reached Saffir–Simpson scale Category 5 intensity. North Atlantic Major Hurricane Michael’s landfall intensity of 140 kt was the fourth strongest for any continental U.S. hurricane landfall in the 168-year record. Michael caused more than 30 fatalities and 25billion(U.S.dollars)indamages.InthewesternNorthPacific,SuperTyphoonMangkhutledto160fatalitiesand25 billion (U.S. dollars) in damages. In the western North Pacific, Super Typhoon Mangkhut led to 160 fatalities and 6 billion (U.S. dollars) in damages across the Philippines, Hong Kong, Macau, mainland China, Guam, and the Northern Mariana Islands. Tropical Storm Son-Tinh was responsible for 170 fatalities in Vietnam and Laos. Nearly all the islands of Micronesia experienced at least moderate impacts from various tropical cyclones. Across land, many areas around the globe received copious precipitation, notable at different time scales. Rodrigues and Réunion Island near southern Africa each reported their third wettest year on record. In Hawaii, 1262 mm precipitation at Waipā Gardens (Kauai) on 14–15 April set a new U.S. record for 24-h precipitation. In Brazil, the city of Belo Horizonte received nearly 75 mm of rain in just 20 minutes, nearly half its monthly average. Globally, fire activity during 2018 was the lowest since the start of the record in 1997, with a combined burned area of about 500 million hectares. This reinforced the long-term downward trend in fire emissions driven by changes in land use in frequently burning savannas. However, wildfires burned 3.5 million hectares across the United States, well above the 2000–10 average of 2.7 million hectares. Combined, U.S. wildfire damages for the 2017 and 2018 wildfire seasons exceeded $40 billion (U.S. dollars)

    Estimating the global conservation status of more than 15,000 Amazonian tree species

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