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Coral‐based stable oxygen isotopes (δ18O) have been used as a proxy for sea surface temperature (SST) since the 1970s, and δ18O–SST calibration studies have been fundamental to assure robust and faithful SST reconstructions. Paleoclimatic studies based on corals from the tropical western South Atlantic (TWSA) are scarce, and the available coral species need to be calibrated to improve climate and environmental reconstructions. Siderastrea stellata, a slow‐growing coral, is a potential species to be explored as a coral archive in the TWSA. We provide the first multi‐site δ18O–SST calibration for the coral S. stellata from three locations at the TWSA: Todos os Santos Bay, Tamandaré and the Rocas Atoll. Pseudo‐coral δ18O calculations derived from gridded SSS and SST show that the contributions of SSS and SST to coral δ18O are expected to be different at each site. Weighted least squares linear regressions performed between the δ18O and SST generated the following calibrations equations: δ18O = −0.18 (±0.02) × SST (°C) + 1.90 (±0.47) for Todos os Santos Bay; δ18O = −0.18 (±0.02) × SST (°C) + 1.54 (±0.67) for Tamandaré; and δ18O = −0.16 (±0.03) × SST (°C) + 1.24 (±0.71) for the Rocas Atoll. The δ18O‐SST sensitivity of S. stellata from the TWSA is similar to that of other slow‐growing species of the genus and consistent with the expected δ18O‐SST sensitivity of other species reported in the literature. These calibrations will allow future SST reconstructions based on δ18O records from sub‐fossil and fossil S. stellata, an abundant species in the TWSA. Plain Language Summary: Corals continuously biomineralize calcium carbonate, storing environmental information within their exoskeletons in geochemical and isotopic records that span hundreds of years and making them suitable for high‐resolution climate reconstructions. The stable oxygen isotopes (δ18O) found in corals are an important proxy for revealing past sea surface temperatures (SST) and sea surface salinities (SSS). However, to ensure that this proxy is applicable to reconstruct past SST, further δ18O–SST calibration studies are needed on various regions and species. In this study, we carried out three field work experiments to provide the first multi‐site δ18O–SST calibration of the slow‐growing coral Siderastrea stellata from the western South Atlantic. Despite the slow growth nature of S. stellata corals that poses a challenge to high temporal resolution sampling, we successfully provided new calibration equations for SST reconstruction from three different locations in the western South Atlantic. Our calibration equations can now be applied to reconstruct SST based on coral δ18O records from sub‐fossil and fossil coral cores. Key Points: First multi‐site δ18O‐SST calibrations for the slow‐growing coral Siderastrea stellata from the western South Atlanticδ18O–SST sensitivity for S. stellata varied from −0.15 to −0.19‰ per °C across the different reef environmentsThis study paves the way for using S. stellata δ18O from fossil and subfossil corals for paleoclimate reconstructions from the western South Atlantic [ABSTRACT FROM AUTHOR]

The brain aging process triggers cognitive function impairment, such as memory loss and compromised quality of life. Cognitive impairment is based on bioenergetic status, with reduced glucose uptake and metabolism in aged brains. Anaplerotic substrates are reported to promote mitochondrial ATP generation, having been tested in clinical trials for the treatment of neurological disorders and metabolic diseases. Objectives and Methods: To assess whether the improvement in oxidative capacity ameliorates cognitive function in adults (12 weeks), and aged (22-month-old) C57/6BJ mice, they received (1) a ketogenic diet, (2) a ketogenic diet supplemented with the anaplerotic substance, triheptanoin, or (3) a control diet for 12 weeks. Spontaneous alternation and time spent in a previously closed arm in the Y-maze test and time interacting with an unknown object in the novel object recognition test (NORT) were used to evaluate working memory. Acetylcholinesterase (AChE) activity in the prefrontal lobe, brain left hemisphere, and cerebellum was also evaluated. Glucose transporter 3 (GLUT3) expression in the prefrontal lobe was analyzed by western blotting. Results: The ketogenic diet (KD) reduced spontaneous alternation in aged mice, leading to lower AChE activity in the aged prefrontal lobe and cerebellum, and in the parieto-temporal-occipital lobe of adult mice. Furthermore, KD decreased GLUT3 protein expression in the frontal lobe of the adults. Discussion: Supplementation of KD with triheptanoin prevented memory impairment and showed similar values of AChE activity and GLUT3 expression compared to the controls. Our data suggest that triheptanoin has a potential role in the bioenergetic capacity of the brain, improving cognitive function. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to assess the prevalence of blood‐borne infectious agents in healthy, client‐owned dogs from a blood donor population in Portugal and Spain, and to address the importance of a screening protocol on every donation. Materials and Methods: Client‐owned healthy dogs were tested before each donation on a veterinary blood bank. Blood samples from new potential donors, and from regular donors, were tested by real‐time polymerase chain reaction for Leishmania species, Ehrlichia species, Brucella species, Babesia species and Anaplasma species Serological tests were also performed for Leishmania species, Ehrlichia species and Dirofilaria immitis. All donors were tested for every infectious agent in each donation. Results: The study found that out of a total of 8036 donors and 35,120 samples tested, 3.9% of blood donors tested positive for at least one of the agents, with the most prevalent being Anaplasma species (2.1%). Serological tests also revealed positive results in 14.0% of donors, with the highest percentage for Leishmania species (7.7%). Moreover, the study found that 28.2% of positive results were from dogs with negative results in donations performed 3 to 12 months before, and 18.0% of positive results were recent infections. Clinical Significance: These findings indicate a high prevalence of infectious agents in seemingly healthy, selected dogs eligible to become blood donors in the Iberian Peninsula, highlighting the importance of regular testing on every donation. This study emphasises the importance of a regular screening protocol for every donation instead of annual testing, as is commonly performed in veterinary medicine. [ABSTRACT FROM AUTHOR]

O problema do valor é o problema que surge a partir do seguinte raciocínio: se tanto o conhecimento como a mera crença verdadeira são igualmente úteis, então por qual razão o conhecimento é mais valioso do que a mera crença verdadeira? Apesar de ser formulado inicialmente no diálogo Meno, de Platão, o problema do valor parece ter recebido pouca atenção desde então. Na epistemologia contemporânea, o problema do valor volta a ser central, sendo uma exigência a uma boa teoria do conhecimento ser capaz também de explicar o valor do conhecimento. Recentemente, novas demandas ao problema do valor surge, exigindo que se explique não só porque o conhecimento é mais valioso, mas também porque o conhecimento possui valor final. Neste artigo, duas respostas ao problema do valor que foram formuladas recentemente são analisadas, a saber, a resposta confiabilista e a resposta da epistemologia das virtudes, e se concluirá que ambas falham em explicar o valor final do conhecimento. O problema do valor é o problema que surge a partir do seguinte raciocínio: se tanto o conhecimento como a mera crença verdadeira são igualmente úteis, então por qual razão o conhecimento é mais valioso do que a mera crença verdadeira? Apesar de ser formulado inicialmente no diálogo Meno, de Platão, o problema do valor parece ter recebido pouca atenção desde então. Na epistemologia contemporânea, o problema do valor volta a ser central, sendo uma exigência a uma boa teoria do conhecimento ser capaz também de explicar o valor do conhecimento. Recentemente, novas demandas ao problema do valor surge, exigindo que se explique não só porque o conhecimento é mais valioso, mas também porque o conhecimento possui valor final. Neste artigo, duas respostas ao problema do valor que foram formuladas recentemente são analisadas, a saber, a resposta confiabilista e a resposta da epistemologia das virtudes, e se concluirá que ambas falham em explicar o valor final do conhecimento.

Copyright of Revista Veterinaria is the property of Universidad Nacional del Nordeste and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Veterinaria is the property of Universidad Nacional del Nordeste and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)