Carbon-modified titanium oxide materials for photocatalytic water and air decontamination

Titanium oxide-based materials with different physical and chemical features were synthetized aiming at removing organic pollutants from both water and air media. The materials were produced employing two different heating methodologies (thermal, T and hydrothermal, H) at distinct temperatures resulting in porous materials. These materials were also modified with either graphene oxide (GO) or carbon nanotubes (CNT), using an in-situ approach. All materials were tested as photocatalysts using ultra-violet (UV), visible (Vis) and solar radiation. Rhodamine B (RhB) and benzene were used as representative pollutants in water and air, respectively. The addition of carbon to the catalysts improved the removal of both pollutants. In the case of the photocatalytic degradation of rhodamine B, under both UV and Vis light, it was found that, the materials containing carbon nanostructures allowed the highest degradation degree, while the photosensitisation phenomenon became negligible. The best catalyst is the one containing CNT (2.98 wt% of C) and thermally treated at 300 °C (T300_CNT). This material showed higher degradation ability than the commercial TiO2 nanopowder Degussa P25 (P25) under Vis light. Regarding benzene removal, the samples thermally treated at 300 °C and modified with CNT and GO (T300_CNT and T300_GO, respectively) outperformed Degussa P25. The former material was successfully reused in the photocatalytic degradation of benzene over 6 consecutive cycles.publishe

Nanostructured transparent solutions for UV-shielding: recent developments and future challenges

Ultraviolet (UV) radiation is known to promote health concerns that can manifest over both short and long terms. Aging, sunburn, skin cancer, and other conditions are related to UV radiation. Medication can also be negatively affected by this radiation. Moreover, UV radiation modifies the taste, colour, and texture of food, and may compromise its suitability for human consumption. Therefore, the development of UV-shielding materials attracts considerable research interest for numerous applications, such as UV-light resistant packaging, sunscreens, contact lenses, coatings, and even clothes. UV-shielding materials arise from the dispersion of a UV-absorber of inorganic (such as ZnO, TiO2, CeO2) or organic (such as lignin, nanocellulose) nature into a matrix of high transparency (usually polymer or glass based). The most common types of UV-absorbers are semiconductor particles, quantum dots, or a hybrid approach combining both. However, inhomogeneous dispersion and large size distributions of the absorbing agent usually compromise the transparency of the UV-shielding material. The goal of the current study is to present the newest and most innovative approaches regarding the development of nanostructured transparent solutions for UV-shielding.publishe

Perfil metabólico de vacas mestiças leiteiras com baixo escore de condição corporal no periparto

Objetivou-se avaliar o perfil metabólico energético, proteico e enzimático de vacas mestiças leiteiras com baixo escore de condição corporal (ECC) no periparto. Foram colhidas amostras sanguíneas uma semana antes do parto, no dia do parto, e aos sete, 14, 21, 28 e 43 dias pós-parto (DPP) de 36 animais, com média de ECC de 2,6±0,5, com eutocia e pós-parto fisiológico e sem tratamentos nesta fase. Analisaram-se as concentrações séricas de proteínas totais, albumina e globulinas para o perfil protéico; AST, ALT, GGT e fosfatase alcalina para o perfil enzimático; ácidos graxos não-esterificados (NEFA), β-hidroxibutirato (BHBA), triglicerídeos, colesterol e lipoproteínas (VLDL, HDL e LDL) para o perfil energético. As vacas apresentaram no pré-parto hipoproteinemia, hipoalbuminemia, hipocolesterolemia e aumento das enzimas GGT e AST. No dia do parto houve lipólise e hipoglobulinemia. Concluiu-se que vacas mestiças leiteiras com baixo ECC apresentam balanço energético negativo, hipoproteinemia com hipoalbuminemia e lesão hepática no periparto, com restabelecimento aos 30 DPP, mas não recuperam sua condição corporal até o final do puerpério

Avaliação de peptídeo natriurético em cães doentes renais crônicos

RESUMO: Na doença renal crônica (DRC), a hipertensão arterial é uma das complicações mais comuns, que pode estar associada a liberação dos peptídeos natriuréticos e a hipertrofia ventricular no homem. Em cães os peptídeos natriuréticos são estudados como biomarcadores cardíacos, mas ainda se desconhece sua função em cães com DRC. Desta forma, este estudo teve como objetivo relacionar a concentração sérica de peptídeo natriurético B aos achados de pressão arterial, eletrocardiográficos, eletrolíticos, hematológicos e bioquímicos séricos e urinários em cães nos distintos estágios da DRC. Foram constatadas diferenças significativas na relação de proteína creatinina urinária (UPC, p=0,006), anemia, creatinina e uréia sérica (p<0,001) nos grupos de doentes renais comparado com saudáveis. Apesar das variações de pressão arterial, amplitude e intervalo QRS e fósforo não serem significativas, foi observada tendência de alteração desses valores com o avanço da doença. Não foi observado correlação entre BNP (peptídeo natriurético cerebral) e DRC

Relation between anaemia and bone marrow features and serum erythropoietin in dogs with chronic kidney disease

ABSTRACT: Chronic anaemia is one of the most severe complications of chronic kidney disease, contributing to morbidity and mortality caused by the disease; therefore, bone marrow cytological evaluation is needed to monitor the progression of anaemia. This study aimed to correlate the anaemia in dogs at different stages of chronic kidney disease with their serum biochemistry, myelogram results and serum erythropoietin findings. Sixty-three dogs were grouped according to International Renal Interest Society (IRIS) classification in stages 1, 2, 3 and 4. Haematologic, serum and urinary biochemistry and serum erythropoietin were performed for comparison with the findings of bone marrow cytology obtained by aspiration of the manubrium. Cytological findings for erythroid hypoplasia were described in 93.65% of dogs, and the anaemia was observed in 84.1% of them. The haematological findings were correlated with azotaemia (p<0.05). It was concluded that the erythroid hypoplasia has correlation with persistent anaemia in dogs at all stages of chronic kidney disease, with iron deficiency in dogs in the early stages and with peripheral destruction of erythrocytes caused by azotaemia