Exceptionally large room-temperature ferroelectric polarization in the novel PbNiO3 multiferroic oxide

We present a study based on several advanced First-Principles methods, of the recently synthesized PbNiO3 [J. Am. Chem. Soc 133, 16920 (2011)], a rhombohedral antiferromagnetic insulator which crystallizes in the highly distorted R3c crystal structure. We find this compound electrically polarized, with a very large electric polarization of about 100 (\muC/cm)^2, thus even exceeding the polarization of well-known BiFeO3. PbNiO3 is a proper ferroelectric, with polarization driven by large Pb-O polar displacements along the [111] direction. Contrarily to naive expectations, a definite ionic charge of 4+ for Pb ion can not be assigned, and in fact the large Pb 6s-O 2p hybridization drives the ferroelectric distortion through a lone-pair mechanism similar to that of other Pb- and Bi-based multiferroic

Pleural mesothelioma and lung cancer risks in relation to occupational history and asbestos lung burden.

BACKGROUND: We have conducted a population-based study of pleural mesothelioma patients with occupational histories and measured asbestos lung burdens in occupationally exposed workers and in the general population. The relationship between lung burden and risk, particularly at environmental exposure levels, will enable future mesothelioma rates in people born after 1965 who never installed asbestos to be predicted from their asbestos lung burdens. METHODS: Following personal interview asbestos fibres longer than 5 µm were counted by transmission electron microscopy in lung samples obtained from 133 patients with mesothelioma and 262 patients with lung cancer. ORs for mesothelioma were converted to lifetime risks. RESULTS: Lifetime mesothelioma risk is approximately 0.02% per 1000 amphibole fibres per gram of dry lung tissue over a more than 100-fold range, from 1 to 4 in the most heavily exposed building workers to less than 1 in 500 in most of the population. The asbestos fibres counted were amosite (75%), crocidolite (18%), other amphiboles (5%) and chrysotile (2%). CONCLUSIONS: The approximate linearity of the dose-response together with lung burden measurements in younger people will provide reasonably reliable predictions of future mesothelioma rates in those born since 1965 whose risks cannot yet be seen in national rates. Burdens in those born more recently will indicate the continuing occupational and environmental hazards under current asbestos control regulations. Our results confirm the major contribution of amosite to UK mesothelioma incidence and the substantial contribution of non-occupational exposure, particularly in women

Optimising the inherent fire capacity of structures

This paper introduces a structural design optimisation methodology aimed at minimising the consequences of a fire. The methodology considers the trade-off between implementing passive fire protection measures and enhancing a structure's “inherent fire capacity”, defined as its ability to retain integrity/functionality without additional fire safety measures. The feasibility of the methodology is demonstrated through the fire safety design of a single-span, steel girder bridge. The optimisation process generates multiple Pareto-optimal solutions for minimising the maximum bridge deflection after a given fire exposure time. Passive protection ensures the bridge's functionality when facing a heavy goods vehicle fire. In the case of exposure to a car fire, solutions requiring fire protection in specific limited girder regions are identified. The decision-making process is further supported by investigating the robustness of the solutions to uncertainties in material properties and the heat flux model

Exceptionally strong magnetism in 4d perovskites RTcO3 (R=Ca,Sr,Ba)

The evolution of the magnetic ordering temperature of the 4d3 perovskites RTcO3 (R=Ca,Sr,Ba) and its relation with its electronic and structural properties has been studied by means of hybrid density functional theory and Monte Carlo simulations. When compared to the most widely studied 3d perovskites the large spatial extent of the 4d shells and their relatively strong hybridization with oxygen weaken the tendency to form Jahn-Teller like orbital ordering. This strengthens the superexchange interaction. The resulting insulating G-type antiferromagnetic ground state is characterized by large superexchange coupling constants (26-35 meV) and Neel temperatures (750-1200 K). These monotonically increase as a function of the R ionic radius due to the progressive enhancement of the volume and the associated decrease of the cooperative rotation of the TcO6 octahedra.Comment: 4 pages, 3 figure

Integração lavoura-pecuária no Norte do Paraná.

Principais modalidades do SILP no Norte do Paraná. Fundamentos do SILP. A qualidade do solo no SILP. Produtividade vegetal e animal em SILP no Norte do Paraná

Vitamin E in Viral Inactivated Vaccines

Abstract This research aimed at verifying whether vitamin E added to inactivated and emulsified vaccines enhances the immune response to viral antigens in chicken. Three hundred and twenty broilers (males and females) and 16 types of vaccines, varying in viral antigen [Newcastle disease virus, egg drop syndrome 1976 virus (EDS76V), and infectious bursal disease virus] and vitamin E amount (replacing 10, 20, and 30% of mineral oil) were used. Results show that vaccines with vitamin E, especially when it replaces 20 or 30% of mineral oil, induces a more rapid and higher antibody response than control vaccines. An adjuvant effect of vitamin E was also present in viral vaccine lacking bacterial antigens. Apart from vitamin E content, the Newcastle disease virus and infectious bursal disease virus monovalent vaccines induced higher titers of specific circulating antibodies in birds than did trivalent vaccines

the occurrence of deep pectoral myopathy in roaster chickens

A field study was conducted to determine the incidence of Deep Pectoral Myopathy (DPM) in male roaster chickens reared under intensive conditions, processed at different ages (from 47 to 65d), and belonging to two commercial genotypes (Ross508; Cobb500). The study was carried out in a major Italian processing plant on a total of 120,700 roaster chickens chosen at random from 151 flocks during a 6 months period. The evaluation of DPM was performed on Pectoralis minor muscles and consisted in a visual assessment of the presence/absence of the myopathy as well as the determination of muscle damage level as being in an "early" (hemorrhagic appearance) or "old" (grey/green discoloration) developing stage. The incidence of carcasses affected by DPM was found to be 0.84% (0.62 and 0.22% in early and old stages, respectively). The range in the incidence of total DPM was fairly large and varied from 0.0 to 16.7%. Considerable variations were also observed for early (range: 0.0 to 12,0%) and old (range: 0.0 to 5.6%) developing stages. Considering the effect of genotype, Ross508 exhibited a higher incidence of DPM in respect with Cobb500 roasters (1.27 vs. 0.35%; P < 0.01). This result was due to the higher incidence of carcasses affected by both early (0.94 vs. 0.26%; P < 0.01) and old (0.33 vs. 0.09%; P < 0.01) developing stages of DPM in Ross508 birds. In conclusions, this study has shown that the occurrence of Deep Pectoral Myopathy in male roaster chickens may be economically significant to the industry as a whole

Variabilidade espacial da produtividade da soja e da condutividade elétrica de um Latossolo Bruno.

A condutividade elétrica (CE) do solo tem sido utilizada como uma variável que se correlaciona com características do solo. No entanto existem poucas informações sobre sua relação com a produtividade das culturas. O efeito da variabilidade espacial da CE de um Latossolo Bruno sob sistema plantio direto sobre a produtividade da soja foi avaliado em uma área de 18,9 ha localizada em Guarapuava/PR. A CE foi determinada por meio do equipamento Veris 3100®, nas camadas de 0 a 0,3 m e 0 a 0,9 m de profundidade. A produtividade da soja foi determinada com uma colhedora autopropelida de grãos equipada com monitor de colheita. Os dados foram submetidos à análise geoestatística considerando 210 pontos amostrais distribuídos uniformemente pela área. A CE e a produtividade da soja apresentaram dependência espacial e foram mapeadas. A produtividade da soja foi significativamente e inversamente correlacionada com a CE determinada a 0-0,3 m e 0-0,9 m. O melhor ajuste do semivariograma, assim como a melhor correlação com a produtividade da soja, foi observada para a CE medida na camada de 0-0,9 m. A CE é um parâmetro útil na definição de zonas de manejo diferenciadas dentro de uma lavoura, pois apresenta alta dependência especial, é correlacionada à produtividade da soja e, ainda, é de rápida e fácil determinação a nível de campo. Spatial variability of soybean yields and soil electrical conductivity in a Haplohumox. Soil electrical conductivity (EC) has been used as a variable correlated with soil characteristics. However, little information about the relationship between EC and crop yield is currently available. The effect of spatial variability of CE determined in a Haplohumox managed under long-term no-tillage on soybean yields was assessed in an agricultural area with 18.9 ha located at Guarapuava County, Paraná State, Southern Brazil. EC values were determined through the equipment Veris 3100® in the layers of 0-0.3 m and 0-0.9 m depth. Soybean yields were evaluated through a combine equipped with harvest monitor. The data were submitted to geostatistical analysis considering 210 sampling points evenly distributed on the area. EC and soybean yield presented spatial dependency and were mapped. Soybean yields were negatively and significantly correlated with EC values determined at 0-0.3 and 0-0.9 depth. The best semivariogram adjustments, as well as the best correlation with soybean yields, were obtained to EC measured at 0-0.9 m depth. EC is a useful parameter to define differentiated management zones inside a crop area, since it presents high spatial dependency, correlation with soybean yields and fast and easy determination at field level