Late Bronze Age in Serra do Socorro (Mafra, Torres Vedras): 2007 and 2008 Archaeological Field Work

info:eu-repo/semantics/publishedVersio

Fed-Batch Synthesis of Poly(3-Hydroxybutyrate) and Poly(3-Hydroxybutyrate-co-4-Hydroxybutyrate) from Sucrose and 4-Hydroxybutyrate Precursors by Burkholderia sacchari Strain DSM 17165

Based on direct sucrose conversion, the bacterium Burkholderia sacchari is an excellent producer of the microbial homopolyester poly(3-hydroxybutyrate) (PHB). Restrictions of the strain’s wild type in metabolizing structurally related 3-hydroxyvalerate (3HV) precursors towards 3HV-containing polyhydroxyalkanoate (PHA) copolyester calls for alternatives. We demonstrate the highly productive biosynthesis of PHA copolyesters consisting of 3-hydroxybuytrate (3HB) and 4-hydroxybutyrate (4HB) monomers. Controlled bioreactor cultivations were carried out using saccharose from the Brazilian sugarcane industry as the main carbon source, with and without co-feeding with the 4HB-related precursor γ-butyrolactone (GBL). Without GBL co-feeding, the homopolyester PHB was produced at a volumetric productivity of 1.29 g/(L·h), a mass fraction of 0.52 g PHB per g biomass, and a final PHB concentration of 36.5 g/L; the maximum specific growth rate μmax amounted to 0.15 1/h. Adding GBL, we obtained 3HB and 4HB monomers in the polyester at a volumetric productivity of 1.87 g/(L·h), a mass fraction of 0.72 g PHA per g biomass, a final PHA concentration of 53.7 g/L, and a μmax of 0.18 1/h. Thermoanalysis revealed improved material properties of the second polyester in terms of reduced melting temperature Tm (161 °C vs. 178 °C) and decreased degree of crystallinity Xc (24% vs. 71%), indicating its enhanced suitability for polymer processing

Novi soj bakterije, izoliran iz bolivijskog slanog jezera, prikladan za proizvodnju poli[(R)-3-hidroksibutirata]

Poly[(R)-3-hydroxybutyrate] (PHB) constitutes a biopolymer synthesized from renewable resources by various microorganisms. This work focuses on finding a new PHB-producing bacterium capable of growing in conventional media used for industrial biopolymer production, its taxonomical identification, and characterization of its biopolymer. Thus, a bacterial isolation process was carried out from environmental samples of water and mud. Among the isolates, strain S29 was selected and used in a fed-batch fermentation to generate a biopolymer. This biopolymer was recovered and identified as PHB homopolymer. Surprisingly, it featured several fractions of different molecular masses, and thermal properties unusual for PHB. Hence, the microorganism S29, genetically identified as a new strain of Bacillus megaterium, proved to be interesting not only due to its growth and PHB accumulation kinetics under the investigated cultivation conditions, but also due to the thermal properties of the produced PHB.Poli[(R)-3-hidroksibutirat] (PHB) je biopolimer kojega sintetiziraju različiti mikroorganizmi iz obnovljivih izvora. Težište je rada bilo na pronalasku novog soja bakterije koji može proizvesti PHB na različitim industrijskom podlogama, te provesti taksonomsku identifikaciju soja i karakterizaciju biopolimera. Stoga su iz uzoraka vode i mulja izolirani sojevi bakterija, te je šaržnim postupkom fermentacije s pritokom supstrata pomoću odabranog soja S29 proizveden biopolimer, kasnije određen kao homopolimer PHB. Iznenađujuće je što je biopolimer imao više frakcija različitih molekularnih masa i termička svojstva neuobičajena za PHB. Time je potvrđeno da je novi soj bakterije Bacillus megaterium S29 zanimljiv ne samo zbog kinetičkih značajki rasta i akumulacije PHB, već i zbog termičkih svojstava proizvedenog biopolimera

Novel Poly[(R)-3-Hydroxybutyratel-producing bacterium isolated from a bolivian hypersaline lake

Poly [ ( R )-3-hydroxybutyrate ] (PHB) constitutes a biopolymer synthesized from renew- able resources by various microorganisms. This work focuses on finding a new PHB-produc- ing bacterium capable of growing in conventional media used for industrial biopolymer production, its taxonomical identification, and characterization of its biopolymer. Thus, a bacterial isolation process was carried out from environmental samples of water and mud. Among the isolates, strain S29 was selected and used in a fed-batch fermentation to gene- rate a biopolymer. This biopolymer was recovered and identified as PHB homopolymer. Surprisingly, it featured several fractions of different molecular masses, and thermal prop- erties unusual for PHB. Hence, the microorganism S29, genetically identified as a new strain of Bacillus megaterium , proved to be interesting not only due to its growth and PHB accumulation kinetics under the investigated cu ltivation conditions, but also due to the thermal properties of the produced PHBPostprint (published version

O ENSINO DE FILOSOFIA NA RESIDÊNCIA PEDAGÓGICA: UMA EXPERIÊNCIA COM A CONFECÇÃO DE JORNAIS FILOSÓFICOS

Este trabalho faz parte dossiê temático associado ao II Seminário da RP/UFT, com o tema: “Formação e prática docente – concepções, trajetórias e desafios da Residência Pedagógica da UFT". A estrutura não comporta resumo

Obesity influences the development of bisphosphonate-induced osteonecrosis in Wistar rats

Medication-related osteonecrosis of the jaw (MRONJ) is characterized by bone exposure for more than eight weeks in patients who have used or been treated with antiresorptive or antiangiogenic drugs, without a history of radiation therapy or metastatic diseases in the jaws. Obesity is associated with changes in periodontal tissues and oral microbiota that are linked to bone alterations. This study aimed to analyze the influence of obesity on the development of bisphosphonate-induced osteonecrosis. The experiment randomly and simply divided 24 male Wistar rats (Rattus norvegicus) into four groups: healthy, with osteonecrosis, obese, and obese with osteonecrosis (n=6 per group). Osteonecrosis was induced through weekly intraperitoneal injection for eight weeks at a dose of 250 µg/kg of zoledronic acid in a 4 mg/5 mL solution, combined with trauma (exodontia). Obesity was induced through a high glycaemic index diet. Each group was qualitatively and quantitatively evaluated regarding the development of models and pathological anatomy of the lesions. The results were expressed in mean percentage and standard deviation and statistically analyzed using one-way analysis of variance (ANOVA) followed by Tukey's post-hoc test, with a significance level of 5% (p<0.05) to establish differences found between the groups. Animals in the osteonecrosis group and the obese with osteonecrosis group presented larger necrosis areas (averages: 172.83±18,19 µm2 and 290.33±15,77 µm2, respectively) (p<0,0001). Bone sequestration, hepatic steatosis, and increased adipocyte size were observed in the obese group (average: 97.75±1.91 µm2) and in the obese with osteonecrosis group (average: 98.41±1.56 µm2), indicating greater tissue damage in these groups (p<0,0001). All parameters analyzed (through histological, morphometric, and murinometric analyses) increased for the obese and obese with osteonecrosis groups, suggesting a possible influence of obesity on the results. However, further studies are needed to confirm the role of obesity in the possible exacerbation of osteonecrosis and understand the underlying mechanisms

Analysis of dengue cases according to clinical severity, São Luís, Maranhão, Brazil

Severe dengue cases have increased in Brazil since 2001, with the first records in Maranhão dating back to 2002. The aim of this study was to determine the prevalence of severe dengue cases by age group and the possible risk factors. This was a study of secondary data on dengue in residents of São Luís, Maranhão, Brazil, using probable cases notified to the National Mandatory Reporting System (SINAN) from 2002 to 2011. The diagnosis and classification of dengue were based on the Brazilian Ministry of Health criteria: dengue fever (DF), dengue hemorrhagic fever (DHF) and dengue fever with complications (DWC). DHF and DWC were considered severe dengue, and DF was classified as non-severe dengue. A logistic regression analysis was performed with severe dengue as the outcome. During the study period, 1,229 cases of severe dengue were reported; of these, 812 in patients under the age of 15 (66%). Among the risk factors evaluated, age under 15 years old (OR = 3.10, 95% CI = 2.69-3.57, p-value = 0.001) was associated with severe dengue. The prevalence of severe dengue in children under the age of 15 was higher, and only this age group was associated with the occurrence of severe dengue

Estado nutricional e consumo alimentar de vegetarianos estritos e não estritos

Introdução: O número de adeptos ao vegetarianismo tem crescido consideravelmente. Observa-se que, entre as vantagens de se adotar uma dieta vegetariana, está o menor risco de desenvolver sobrepeso e obesidade, o que pode estar relacionado com o alto consumo de vegetais e práticas importantes de estilo de vida. Objetivos: Avaliar o estado nutricional e a frequência do consumo alimentar de vegetarianos não estritos e estritos. Métodos: Estudo transversal descritivo, realizado com participantes do grupo “Vegans SLZ”, de ambos os sexos e com idade a partir de 18 anos. A coleta de dados ocorreu de janeiro a março de 2020. Foi realizada aplicação de questionários sobre dados de frequência do consumo alimentar, socioeconômico e de estilo de vida e a aferição de medidas de peso corporal, estatura e de percentuais de gordura corporal e massa muscular. Os dados foram tabulados no Excel 2010® e analisados no programa estatístico R Studio versão 3.6.1. Resultados: Dos 43 vegetarianos avaliados, a maioria seguia a dieta vegetariana estrita (55,81%) e era eutrófica (62,79%), 32,56% apresentaram alto percentual de gordura corporal e 53,49% percentual de massa magra corporal normal. Foi frequente o consumo de pães, cereais, tubérculos, leguminosas, oleaginosas, frutas e verduras, e 41% consumiam alimentos industrializados de 4 a 7 vezes por semana. Conclusões: A maioria da amostra tinha estado nutricional eutrófico e consumo regular de todos os grupos alimentares, porém com importante consumo de alimentos industrializados

Liquefied Wood as Inexpensive Precursor-Feedstock for Bio-Mediated Incorporation of (R)-3-Hydroxyvalerate into Polyhydroxyalkanoates

Liquefied wood (LW) prepared in a microwave process was applied as a novel; inexpensive precursor feedstock for incorporation of (R)-3-hydroxyvalerate (3HV) into polyhydroxyalkanoate (PHA) biopolyesters in order to improve the biopolyester's material quality; Cupriavidus necator was applied as microbial production strain. For proof of concept, pre-experiments were carried out on a shake flask scale using different mixtures of glucose and LW as carbon source. The results indicate that LW definitely acts as a 3HV precursor, but, at the same time, displays toxic effects on C. necator at concentrations exceeding 10 g/L. Based on these findings, PHA biosynthesis under controlled conditions was performed using a fed-batch feeding regime on a bioreactor scale. As major outcome, a poly(3HB-co-0.8%-3HV) copolyester was obtained displaying a desired high molar mass of M-w = 5.39 x 10(5) g/mol at low molar-mass dispersity (D-M of 1.53), a degree of crystallinity (X-c) of 62.1%, and melting temperature T-m (176.3 degrees C) slightly lower than values reported for poly([R]-3-hydroxybutyrate) (PHB) homopolyester produced by C. necator; thus, the produced biopolyester is expected to be more suitable for polymer processing purposes.Postprint (published version

Influence of glycerol on poly(3-hydroxybutyrate) production by Cupriavidus necator and Burkholderia sacchari

Glycerol is a co-product of many industrial processes and is generated in large quantities from different origins. In this study, glycerol is used as a cheap carbon source for the production of poly(3- hydroxybutyrate) (PHB) with two different collection strains, Cupriavidus necator and Burkholderia sacchari, in order to provide an alternative outlet for glycerol and produce value-added bioproducts. The objective of this work was to study the influence of this carbon source on their growth kinetics, on their polymer production, and on the molecular mass of the produced biopolymer. Therefore, fermentations in bioreactors were carried out with these strains. Different results for both strains were obtained showing, for the first time, a high cell dry mass and growth rate, when glycerol was used together with glucose in the fermentation with C. necator. In the first fermentation with B. sacchari using glycerol as a sole carbon source, the strain properly developed synthesizing PHB. The biopolymers obtained from both fermentations with glycerol showed low molecular masses about 300 kDa with a polydispersity of 4.72 with C. necator, and 200 kDa with polydispersity of 2.50 with B. sacchari.Postprint (author's final draft