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- Death among primates: a critical review of non-human primate interactions towards their dead and dyingPublication . Goncalves, Andre; Carvalho, SusanaFor the past two centuries, non-human primates have been reported to inspect, protect, retrieve, carry or drag the dead bodies of their conspecifics and, for nearly the same amount of time, sparse scientific attention has been paid to such behaviours. Given that there exists a considerable gap in the fossil and archaeological record concerning how early hominins might have interacted with their dead, extant primates may provide valuable insight into how and in which contexts thanatological behaviours would have occurred. First, we outline a comprehensive history of comparative thanatology in non-human primates, from the earliest accounts to the present, uncovering the interpretations of previous researchers and their contributions to the field of primate thanatology. Many of the typical behavioural patterns towards the dead seen in the past are consistent with those observed today. Second, we review recent evidence of thanatological responses and organise it into distinct terminologies: direct interactions (physical contact with the corpse) and secondary interactions (guarding the corpse, vigils and visitations). Third, we provide a critical evaluation regarding the form and function of the behavioural and emotional aspects of these responses towards infants and adults, also comparing them with non-conspecifics. We suggest that thanatological interactions: promote a faster re-categorisation from living to dead, decrease costly vigilant/caregiving behaviours, are crucial to the management of grieving responses, update position in the group's hierarchy, and accelerate the formation of new social bonds. Fourth, we propose an integrated model of Life-Death Awareness, whereupon neural circuitry dedicated towards detecting life, i.e. the agency system (animate agency, intentional agency, mentalistic agency) works with a corresponding system that interacts with it on a decision-making level (animate/inanimate distinction, living/dead discrimination, death awareness). Theoretically, both systems are governed by specific cognitive mechanisms (perceptual categories, associative concepts and high-order reasoning, respectively). Fifth, we present an evolutionary timeline from rudimentary thanatological responses likely occurring in earlier non-human primates during the Eocene to the more elaborate mortuary practices attributed to genus Homo throughout the Pleistocene. Finally, we discuss the importance of detailed reports on primate thanatology and propose several empirical avenues to shed further light on this topic. This review expands and builds upon previous attempts to evaluate the body of knowledge on this subject, providing an integrative perspective and bringing together different fields of research to detail the evolutionary, sensory/cognitive, developmental and historical/archaeological aspects of primate thanatology. Considering all these findings and given their cognitive abilities, we argue that non-human primates are capable of an implicit awareness of death.
- Effects of calcium carbonate inclusion in low fishmeal diets on growth, gastrointestinal pH, digestive enzyme activity and gut bacterial community of European sea bass (Dicentrarchus labrax L.) juvenilesPublication . Parma, Luca; Yufera, Manuel; Navarro-Guillen, Carmen; Moyano, Francisco J.; Soverini, Matteo; D'Amico, Federica; Candela, Marco; Fontanillas, Ramon; Gatta, Pier Paolo; Bonaldo, AlessioFishmeal (FM) possesses one of the highest buffering capacities in comparison to most alternative vegetable aquafeed ingredients and its decreasing content in current formulations might affect the ideal gastrointestinal environment for digestive enzyme action and gut bacterial community of carnivorous fish species. A study was undertaken, therefore, to assess growth response, gastrointestinal pH, digestive enzyme activity and gut bacterial community of European sea bass (Dicentrarchus labrax L.) juveniles fed low FM diets (10% FM) with or without a feed buffering additive, calcium carbonate (FM10 + B and FM10, respectively) in comparison to a standard FM diet (20% FM, FM20). Three isonitrogenous and isolipidic extruded diets were fed to triplicate fish groups of 80 individuals (initial weight: 23 g) to overfeeding over 64 days. No significant differences due to low FM dietary levels were observed in final body weight, specific growth rate, feed intake, feed and protein efficiency. Low FM diet did not affect gastrointestinal pH in the stomach, anterior intestine, mid-intestine and hindgut at 0, 4, 8 and 12 hours post meal (hpm) while the inclusion of calcium carbonate in low FM diet seems to slightly increase the pH in the hindgut at 12 hpm. The absence of significant differences of pepsin, chymotrypsin, amylase and lipase activity suggests a comparable digestive efficiency among treatments although trypsin activity was slightly reduced in low FM diets after 4 hpm. Decreasing FM content seems to exert an effect on the overall gut bacterial community analysed by next-generation sequencing even if no significant effects on specific bacterial component were detected. The gut bacterial community in all the treatments was particularly rich in lactic acid bacteria such as Lactobacillus spp. which may provide important beneficial functions for the host and be associated with a healthy intestinal epithelium. According to the results, increasing the feed buffering capacity does not seem to improve digestive conditions while it is feasible to include 10% FM dietary level in practical formulation for European sea bass juveniles without negatively affecting growth, feed efficiency and digestive luminal conditions.
- Industrial production of Phaeodactylum tricornutum for CO2 mitigation: biomass productivity and photosynthetic efficiency using photobioreactors of different volumesPublication . Quelhas, Pedro M.; Trovao, Mafalda; Silva, Joana T.; Machado, Adriana; Santos, Tamara; Pereira, Hugo; Varela, João; Simoes, Manuel; Silva, Joana L.The photosynthetic efficiency (PE) and potential of Phaeodactylum tricornutum for CO2 mitigation in industrial tubular photobioreactors (PBRs) of different volumes were evaluated. A preliminary assay was performed at lab-scale to optimize the salt concentration of the culture medium. Interestingly, salinity did not affect the growth of P. tricornutum at concentrations of 2.5, 5, 10, and 20 g L-1. Higher volumetric productivities were achieved in the 2.5-m(3) tubular PBR (0.235 g L-1 day(-1)), followed by 35- and 10-m(3) PBRs. Maximum areal productivities corresponded to 48.5, 45.0, and 12.8 g m(-2) day(-1) for the 35-, 10-, and 2.5-m(3) PBRs, respectively. PE was thus higher in the 35- and 10-m(3) PBRs (2.21 and 2.08%, respectively). The 10- and 35-m(3) PBR showed CO2 mitigation efficiencies of 60 and 41%, respectively, of the CO2 introduced into the PBR, corresponding to 2.3 and 2.5 g of fixed CO2 per g of biomass. Overall, cultivation of P. tricornutum couples high PE and areal productivity when the industrial PBRs were used, particularly PBRs of larger volumes. This improved PE performance with larger PBR volumes strongly suggests that large-scale cultivation of this diatom holds great potential for industrial CO2 mitigation.
- Neanderthal plant use and pyrotechnology: phytolith analysis from Roc de Marsal, FrancePublication . Wroth, Kristen; Cabanes, Dan; Marston, John M.; Aldeias, Vera; Sandgathe, Dennis; Turq, Alain; Goldberg, Paul; Dibble, Harold L.The plant component of Neanderthal subsistence and technology is not well documented, partially due to the preservation constraints of macrobotanical components. Phytoliths, however, are preserved even when other plant remains have decayed and so provide evidence for Neanderthal plant use and the environmental context of archaeological sites. Phytolith assemblages from Roc de Marsal, a Middle Paleolithic cave site in SW France, provide new insight into the relationship between Neanderthals and plant resources. Ninety-seven samples from all archaeological units and 18 control samples are analyzed. Phytoliths from the wood and bark of dicotyledonous plants are the most prevalent, but there is also a significant proportion of grass phytoliths in many samples. Phytolith densities are much greater in earlier layers, which is likely related to the presence of combustion features in those layers. These phytoliths indicate a warmer, wetter climate, whereas phytoliths from upper layers indicate a cooler, drier environment. Phytoliths recovered from combustion features indicate that wood was the primary plant fuel source, while grasses may have been used as surface preparations.
- Waiting for ICU admission may increase the risk of death-A plea for better resource organizationPublication . Castro, Silvia; Pereira, Isabel Jesus; Dias, Claudia Camila; Granja, CristinaBackground Mortality is high in critically ill patients. In order to study the risk factors associated with mortality in these patients, we conducted an observational retrospective study in the general Intensive Care Unit (ICU) of Faro Hospital. Methods All patients discharged from the general ICU in the year 2015 were evaluated for inclusion. Mortality was characterized in the first 48 hours of ICU stay, at the time of discharge from ICU, and at discharge from hospital. Collected variables included demographic variables (age), and ICU variables: type of ICU admission (scheduled surgery, urgent surgery, medical and trauma), Simplified Acute Physiology Score (SAPS II), main diagnosis, hospital length of stay (HLS) before ICU (BICULS), in ICU (ICULS) and after ICU (AICULS). Results When comparing survivors with non-survivors, we found that age, disease severity expressed by SAPS II and BICULS were significantly higher in non-survivors. After multivariate regression analysis, BICULS was still significantly associated with mortality in the hospital. Conclusion Further studies are needed to characterize whether this longer BICULS is related to non-modifiable prior conditions or whether it is related to delayed ICU admission, which is a modifiable factor.
- Quantum mechanism of light energy propagation through an avian retinaPublication . Zueva, Lidia; Golubeva, Tatiana; Korneeva, Elena; Resto, Oscar; Inyushin, Mikhail; Khmelinskii, Igor; Makarov, VladimirTaking into account the ultrastructure of the Pied Flycatcher foveal retina reported earlier and the earlier reported properties of Muller cell (MC) intermediate filaments (IFs) isolated from vertebrate retina, we proposed a quantum mechanism (QM) of light energy transfer from the inner limiting membrane level to visual pigments in the photoreceptor cells. This mechanism involves electronic excitation energy transfer in a donor-acceptor system, with the IFs excited by photons acting as energy donors, and visual pigments in the photoreceptor cells acting as energy acceptors. It was shown earlier that IFs with diameter 10 nm and length 117 mu m isolated from vertebrate eye retina demonstrate properties of light energy guide, where exciton propagates along such IFs from MC endfeet area to photoreceptor cell area. The energy is mostly transferred via the contact exchange quantum mechanism. Our estimates demonstrate that energy transfer efficiencies in such systems may exceed 80-90%. Thus, the presently developed quantum mechanism of light energy transfer in the inverted retina complements the generally accepted classic optical mechanism and the mechanism whereby Muller cells transmit light like optical fibers. The proposed QM of light energy transfer in the inverted retina explains the high image contrast achieved in photopic conditions by an avian eye, being probably also active in other vertebrates.
- Mercury in archaeological human bone: biogenic or diagenetic?Publication . Emslie, Steven D.; Alderman, Audrey; McKenzie, Ashley; Brasso, Rebecka; Taylor, Alison R.; Molina Moreno, Maria; Cambra-Moo, Oscar; Gonzalez Martin, Armando; Silva, Ana Maria; Valera, António Carlos; Garcia Sanjuan, Leonardo; Vijande Vila, EduardoWe investigated mercury (Hg) in human bone from archaeological sites in the Iberian Peninsula where the cultural use of cinnabar (HgS) as a pigment, offering or preservative in burial practices has been documented from the 4th to 2nd millennia cal B.C. (Late Neolithic, Copper Age and Bronze Age). Previous analyses have shown high levels of total mercury (THg) in human bone at numerous Neolithic and Chalcolithic sites in this region, but the question remains if this mercury entered the bones via diagenetic processes in the soil, especially where cinnabar powder and paint was found associated with the burials, or if it entered the bone via biogenic pathways from exposure to mercury from using cinnabar in life. We analyzed the humerus, femur, and tibia from a total of 30 individual burials from four Neolithic to Bronze Age sites in Iberia and found low to high values of THg in these bones, with the humerus showing significantly more THg concentrations than other skeletal elements when the THg was greater than 1 ppm. This pattern of Hg deposition in skeletal material from different sites and ages strongly suggests a biogenic origin for the mercury. In addition, absence of detectable Hg in bones with high to low values of THg using SEM EDS analysis further discounts diagenetic intrusion of Hg or cinnabar particles into the bone from the soil. It is likely that greater stress and bone remodeling rates from use of heavy tools and other activities in life are responsible for higher THg in the humerus than other skeletal elements, but additional research is needed to verify this.
- A hydrogen-bonded assembly of cucurbit[6]uril and [MoO2Cl2(H2O)(2)] with catalytic efficacy for the one-pot conversion of olefins to alkoxy productsPublication . Nogueira, Lucie S.; Antunes, Margarida M.; Gomes, Ana C.; Cunha-Silva, Luis; Pillinger, Martyn; Lopes, Andre D.; Valente, Anabela A.; Goncalves, Isabel S.The reaction of the macrocyclic cavitand cucurbit[6]uril (CB[6]) and the diaqua complex [MoO2Cl2(H2O)(2)] in hydrochloric acid solution gave a water insoluble supramolecular compound with the general composition 2[MoO2Cl2(H2O)(2)]center dot CB[6]center dot xH(2)O center dot yHCl center dot z(CH3COCH3) (2). Single crystal X-ray diffraction (XRD) analysis revealed the presence of barrel-shape supramolecular entities, {CB[6]center dot 10(H2O)}, aligned in layers which are shifted relative to adjacent layers to form a brick-like pattern. The CB[6]/water hydrogen-bonded entities further engage in intermolecular interactions with water, HCl and [MoO2Cl2(H2O)(2)] molecules to form a three-dimensional (3D) framework. Compound 2 was characterised by thermogravimetric analysis (TGA), IR and Raman vibrational spectroscopy, and C-13{H-1} CP MAS NMR. The reference complex [MoO2Cl2(H2O)(2)]center dot(diglyme)(2) (1) and compound 2 were studied for the oxidative catalytic conversion of olefins (cis-cyclooctene, cyclohexene and styrene) with aqueous H2O2 as oxidant. Using alcohols as solvents, 2 was employed in a one-pot two-stage strategy for converting olefins to alkoxy products, which involves oxidation (with H2O2) and acid chemistry. Mechanistic studies were carried out using different intermediates as substrates, and the type of solvent and substrate scope were investigated. The results demonstrated the ability of the CB[6]/Mo-VI supramolecular adduct to function as an acid-oxidation multifunctional catalyst, and its recovery and reuse via relatively simple procedures.
- Anafilaxia: da fisiopatologia à abordagem emergentePublication . Jorge, CatarinaA anafilaxia é uma síndrome sistémica de início súbito, potencialmente fatal, não sendo possível prever a gravidade total e velocidade de progressão dos sintomas; como tal, a identificação e tratamento precoces são o foco principal de atuação. As principais manifestações clínicas ocorrem nos sistemas mucocutâneo, cardiovascular, respiratório e gastrointestinal. A incidência da anafilaxia tem vindo a aumentar, contudo ainda prevalece subestimada. Os mecanismos fisiopatologicos não são claramente compreendidos e a carência de estudos prospectivos e randomizados limitam a progressão e atualização na abordagem. No presente artigo pretende-se fornecer uma visão geral desta entidade, realçando a importância da identificação precoce, diagnóstico e tratamento emergente, como modificadores de prognóstico.
- Abordagem ao doente traumatizado vertebro-medularPublication . Pappamikail, Lia BrancoA lesão medular define-se como uma lesão da medula espinal que resulta numa alteração, temporária ou permanente, das suas normais funções motora, sensitiva e/ou autonómica. Todos os anos surgem em Portugal aproximadamente 350 novos casos de traumatizados vértebro-medulares (TVM), sendo predominantemente afectados adultos jovens do sexo masculino, mais frequentemente em contexto de acidentes de viação e atropelamentos, mas também em quedas acidentais, desportos radicais, acidentes de mergulho, actos de violência, etc. A lesão vertebro-medular (LVM) traumática é potencialmente devastadora, com potencial de disfunção motora, sensitiva, respiratória, esfincteriana, neurovegetativa, com importante repercussão emocional e psíquica para os doentes e seus familiares. Sabe-se hoje que a lesão medular tem potencial de recuperação, e existe consenso na literatura internacional quanto ao determinismo das primeiras horas que se seguem à lesão no que diz respeito à recuperação, sendo escassas as melhorias registadas após o primeiro ano. É também consensual que a recuperação neurológica é influenciada pela gravidade da lesão, sendo a recuperação funcional mais dependente da idade do doente, nível de lesão medular e abordagem terapêutica na fase aguda.
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