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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123965, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38295596

RESUMO

The simulated distillation curve (ASTM/D-7169) is a quantitative method to determine fractions of crude oils by boiling point temperature ranges (36-720 °C). In this work, 45 samples of typical Colombian crudes were selected, and the samples were produced under conventional process. Also 8 upgraded crude oils under catalytic aquathermolysis conditions at laboratory scale were added. The tests were developed at 270 °C and 800psi (@25 °C) during 66 h of reaction. In addition, 30 samples were selected for density tests, according to the pycnometer method. Subsequently, the crude oil samples under study were diluted in chloroform and analyzed by UV-VIS Spectroscopy. The UV-VIS spectra were correlated with selected properties by using PCA-MLR and PLS models. The distillation curves of the crude oils were modelled using the Riazi probability function. The prediction models of parameters To, A, and B from the Riazi probability function exhibited R2 correlation coefficients, higher than 0.94. The correlation model for the crude oil density showed a much better coefficient, higher than 0.99 and Root-Mean-Squared-Error (RMSE) close to 0.004. Additionally, even more important is the contribution of the use of UV-VIS spectroscopy as a useful tool to quickly evaluate the quality of crude oil.

2.
Health Policy Plan ; 38(Supplement_2): ii36-ii50, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37995268

RESUMO

The spread of COVID-19 in Peru resulted in the declaration of a national health emergency, in which Indigenous peoples were identified as being particularly vulnerable due to their pre-existing poor health indicators and disadvantaged social conditions. The aim of this paper is to examine how the Peruvian government responded to the health and food needs of the Shawi and Ashaninka Indigenous peoples of Peru during the first 18 months of the pandemic (March 2020-August 2021). This study uses both official policy documents and real-world experiences to evaluate policy responses in terms of their immediate impact and their longer-term sustainability and contribution to the improvement of health, well-being and justice for Indigenous communities. Four health and food security responses were evaluated: the Amazon Health Plan and Indigenous Command; food aid; cash aid; and COVID-19 vaccination. We employed the Multidimensional Injustice Framework to analyse the justice implications of the design and implementation of responses. Data collection included 71 interviews with government officials (n = 7), Indigenous leaders (n = 31) and community members (n = 33). The results show how national and regional governments released policies to address the health and food needs of Indigenous peoples directly or indirectly, as part of a broader focus on vulnerable people. However, justice implications were not sufficiently addressed in the design or implementation of the responses. On the distributive dimension, Indigenous communities were prioritized to receive health goods and services, nevertheless, the distribution had shortcomings that impeded their collection and Indigenous food systems and livelihoods were largely overlooked. On the procedural dimension, Indigenous representatives were included to provide culturally sensitive feedback on health interventions, but without funding, and furthermore, the community members had only passive participation. This paper points out the importance of considering and addressing justice implications for more effective and fairer health and food policy responses to current and future health crises.


Assuntos
COVID-19 , Humanos , Peru , Vacinas contra COVID-19 , Justiça Social , Política Nutricional , Segurança Alimentar , Formulação de Políticas , Povos Indígenas
3.
Front Med (Lausanne) ; 10: 1271863, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869162

RESUMO

Introduction: Long-term pulmonary dysfunction (L-TPD) is one of the most critical manifestations of long-COVID. This lung affection has been associated with disease severity during the acute phase and the presence of previous comorbidities, however, the clinical manifestations, the concomitant consequences and the molecular pathways supporting this clinical condition remain unknown. The aim of this study was to identify and characterize L-TPD in patients with long-COVID and elucidate the main pathways and long-term consequences attributed to this condition by analyzing clinical parameters and functional tests supported by machine learning and serum proteome profiling. Methods: Patients with L-TPD were classified according to the results of their computer-tomography (CT) scan and diffusing capacity of the lungs for carbon monoxide adjusted for hemoglobin (DLCOc) tests at 4 and 12-months post-infection. Results: Regarding the acute phase, our data showed that L-TPD was favored in elderly patients with hypertension or insulin resistance, supported by pathways associated with vascular inflammation and chemotaxis of phagocytes, according to computer proteomics. Then, at 4-months post-infection, clinical and functional tests revealed that L-TPD patients exhibited a restrictive lung condition, impaired aerobic capacity and reduced muscular strength. At this time point, high circulating levels of platelets and CXCL9, and an inhibited FCgamma-receptor-mediated-phagocytosis due to reduced FcγRIII (CD16) expression in CD14+ monocytes was observed in patients with L-TPD. Finally, 1-year post infection, patients with L-TPD worsened metabolic syndrome and augmented body mass index in comparison with other patient groups. Discussion: Overall, our data demonstrated that CT scan and DLCOc identified patients with L-TPD after COVID-19. This condition was associated with vascular inflammation and impair phagocytosis of virus-antibody immune complexes by reduced FcγRIII expression. In addition, we conclude that COVID-19 survivors required a personalized follow-up and adequate intervention to reduce long-term sequelae and the appearance of further metabolic diseases.

4.
Nat Commun ; 13(1): 1530, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35318319

RESUMO

The genetic prehistory of human populations in Central America is largely unexplored leaving an important gap in our knowledge of the global expansion of humans. We report genome-wide ancient DNA data for a transect of twenty individuals from two Belize rock-shelters dating between 9,600-3,700 calibrated radiocarbon years before present (cal. BP). The oldest individuals (9,600-7,300 cal. BP) descend from an Early Holocene Native American lineage with only distant relatedness to present-day Mesoamericans, including Mayan-speaking populations. After ~5,600 cal. BP a previously unknown human dispersal from the south made a major demographic impact on the region, contributing more than 50% of the ancestry of all later individuals. This new ancestry derived from a source related to present-day Chibchan speakers living from Costa Rica to Colombia. Its arrival corresponds to the first clear evidence for forest clearing and maize horticulture in what later became the Maya region.


Assuntos
Agricultura , DNA Antigo , América Central , Colômbia , Florestas , Humanos
5.
PLoS One ; 16(8): e0254992, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34383771

RESUMO

Maya archaeologists have long been interested in understanding ancient diets because they provide information about broad-scale economic and societal transformations. Though paleodietary studies have primarily relied on stable carbon (δ13C) and nitrogen (δ15N) isotopic analyses of human bone collagen to document the types of food people consumed, stable sulfur (δ34S) isotope analysis can potentially provide valuable data to identify terrestrial, freshwater, or marine/coastal food sources, as well as determine human mobility and migration patterns. Here we assess applications of δ34S for investigating Maya diet and migration through stable isotope analyses of human bone collagen (δ13C, δ15N, and δ34S) from 114 individuals from 12 sites in the Eastern Maya lowlands, temporally spanning from the Late Preclassic (300 BCE-300 CE) through Colonial periods (1520-1800 CE). Results document a diet dominated by maize and other terrestrial resources, consistent with expectations for this inland region. Because δ34S values reflect local geology, our analyses also identified recent migrants to the Eastern lowlands who had non-local δ34S signatures. When combined with other indicators of mobility (e.g., strontium isotopes), sulfur isotopic data provide a powerful tool to investigate movement across a person's lifespan. This study represents the largest examination of archaeological human δ34S isotope values for the Maya lowlands and provides a foundation for novel insights into both subsistence practices and migration.


Assuntos
Dieta , Migração Humana , Isótopos de Enxofre/análise , Arqueologia , Belize , Osso e Ossos/química , Isótopos de Carbono/análise , Colágeno/química , Geografia , Geologia , Humanos , Isótopos de Nitrogênio/análise , Estatística como Assunto , Fatores de Tempo
7.
Clin Transl Oncol ; 23(5): 931-939, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33768441

RESUMO

Anaemia is defined by the presence of haemoglobin (Hb) levels < 13 g/dL in men and 12 g/dL in women. Up to 39% of cancer patients present it at the time of diagnosis and up to 40% have iron deficiency. Anaemia causes fatigue, functional deterioration and a reduction in the quality of life; it has also been associated with a poorer response to anti-tumour treatment and lower survival. Basic diagnostic tests for anaemia are simple and should be a routine part of clinical practice. These guidelines review the available evidence on the use of different therapies for treating anaemia: erythropoiesis-stimulating agents, iron supplements, and transfusion of blood products.


Assuntos
Anemia/diagnóstico , Anemia/terapia , Hematínicos/uso terapêutico , Ferro/administração & dosagem , Neoplasias/complicações , Algoritmos , Anemia/sangue , Anemia/complicações , Anemia Ferropriva/complicações , Anemia Ferropriva/diagnóstico , Diagnóstico Diferencial , Suplementos Nutricionais/efeitos adversos , Transfusão de Eritrócitos/efeitos adversos , Transfusão de Eritrócitos/métodos , Feminino , Hematínicos/efeitos adversos , Humanos , Ferro/efeitos adversos , Masculino , Oncologia , Neoplasias/mortalidade , Qualidade de Vida , Sociedades Médicas , Espanha
8.
Water Environ Res ; 93(4): 636-644, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33073480

RESUMO

Anammox is a cost-effective and sustainable process for nitrogen removal; however, the production of a physiologically stable inoculum is a critical point in the start-up process. In this work, estuarine sediments were used as incubation seeds to obtain cultures with stable anammox activity. Assays were performed in batch cultures fed with stoichiometric amounts of ammonium and nitrite, analyzing physiological response variables and the microbial community. Estuarine sediments showed a stable anammox process after 90 days, consuming ammonium and nitrite simultaneously with concomitant generation of N2 and nitrate in stoichiometric amounts. In kinetic assays, substrates were fully consumed after 210 hr, exhibiting N2 and nitrate yields of 0.85 and 0.10, respectively. The microbial community analysis using PCR-DGGE indicated the presence of uncultured anammox bacteria and members of the genus Candidatus Jettenia. The results evidenced the achievement of anammox cultures, although their start-up and kinetic characteristics were less favorable than those recorded in man-made systems. PRACTITIONER POINTS: Estuarine sediments were used as incubation seeds to obtain cultures with stable anammox activity. The sediments were fed with stoichiometric amounts of ammonium and nitrite, analyzing the physiological response variables and the microbial community. Sediments showed a stable anammox process after 90 days, converting the substrates into N2 and nitrate according to stoichiometry. Anammox cultures were achieved although their start-up and kinetic characteristics were less favorable than those recorded in man-made systems. Microbial community analysis using PCR-DGGE indicated the presence of uncultured anaerobic ammonia-oxidizing bacterium and members of genus Candidatus Jettenia.


Assuntos
Compostos de Amônio , Nitrogênio , Anaerobiose , Bactérias/genética , Reatores Biológicos , Humanos , Nitritos , Oxirredução
9.
Poult Sci ; 99(9): 4265-4277, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32867971

RESUMO

It has been demonstrated that vitamin D (Vit D) included in diets offers a beneficial effect by improving innate immune responses in chickens. However, its mechanisms of action and the effect on immunosuppressive pathogens, such as infectious bursal disease virus, are not yet known. In the present study, we have studied the immunomodulatory effect of Vit D on the innate immune response in 3 cell lines: fibroblast cells (DF-1), macrophages (HD11), and B cells (DT-40) infected with IBDV (intermediate vaccine) at 2 multiplicity of infections (MOI) (1 and 0.1). Genes associated with innate immune responses (TLR-3, TLR-21, MDA-5, MyD88, TRIF, IRF-7, INF-α, INF-ß, PKR, OAS, viperin, IL-1ß, IL-6, and IL-12) were evaluated at different time points (3, 6, 12, 24, and 36 h after infection, h.p.i). Virus production reached a maximum at 24 h.p.i., which was significantly (P < 0.05) higher in DF-1 cells, followed by HD-11 and DT-40 cells. Mainly in HD-11 cells, there was a significant (P < 0.05) effect of Vit D supplementation on receptors TLR-3, TLR-21, and MDA-5 after 12 h.p.i, independent of MOI. DT-40 cells showed the highest antiviral activity, with a significant (P < 0.05) effect on IRF-7, IFN-ß, OAS, and PKR gene expression, where expression of IRF-7 and IFN-ß correlated positively with Vit D supplementation, while OAS and PKR were independent of Vit D. Proinflammatory cytokines were significantly (P < 0.05) upregulated and found to be Vit D and MOI dependent. In conclusion, this study demonstrated the capacity of IBDV to trigger a strong innate immune response in chicken cells and contributes to the understanding of the activation pathways of innate immunity induced by IBDV and further shows the benefitial effect of Vit D supplementation as an immunomodulator.


Assuntos
Infecções por Birnaviridae , Imunidade Inata , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Vitamina D , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/veterinária , Linhagem Celular , Galinhas , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Técnicas In Vitro , Vitamina D/farmacologia
10.
Sci Data ; 7(1): 167, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493975

RESUMO

Mexico has used two vertical datums-the U.S. National Geodetic Vertical Datum of 1929 (NGVD29) and the North American Vertical Datum of 1988 (NAVD88). Because Mexico started using the NAVD88 as its vertical datum in 2015, most of Mexico's data is referenced to the NGVD29 and recent high resolution data are referenced to the NAVD88. Compounding this situation, satellite-derived Digital Elevation Models (DEMs) are referenced to the Earth Gravimetric Model 96 (EGM96), and no tools are currently available in Mexico to transform elevation data between the aforementioned vertical datums. To overcome this problem, this work presents the development of two surfaces to transform orthometric heights between the NGVD29 and NAVD88 or between the NGVD29 and EGM96 in Mexico. These surfaces can be used by any interested user to transform orthometric heights referenced to the aforementioned datums.

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