Foundation and perspectives of the use of plant extracts as performance enhancers in broilers

Feed is responsible for about 70% of broilers production costs, leading to an increasing number of studies on alternative dietary products that benefit bird performance and lower production costs. Since the 1950s, antimicrobial additives are the most frequently used performance enhancers in animal production and their positive results are observed even in high-challenge conditions. Since the 1990s, due to the ban of the use of some antibiotics as growth promoters and the growing trend of the public to consume natural products, plant extracts have been researched as alternatives to antibiotic growth promoters. The first study that evaluated the antibacterial activities of plant extracts was carried out in 1881; however, they started to be used as flavor enhancers only during the next decades. With the emergence of antibiotics in the 1950s, the use of plant extracts as antimicrobial agents almost disappeared. There are several studies in literature assessing the use of plant extracts, individually or in combination, as antimicrobials, antioxidants, or digestibility enhancers in animal feeds. Research results on the factors affecting their action, such as plant variety, harvest time, processing, extraction, as well as the technology employed to manufacture the commercial product and dietary inclusion levels show controversial results, warranting the need of further research and standardization for the effective use of plant extracts as performance enhancers, when added to animal feeds. This article aims at presenting plant extracts as alternatives to antibiotics, explaining their main modes of action as performance enhancers in broiler production

Convulsions and Shigellosis

The records of 97 children with culture-proven Shigellosis were reviewed in order to assess the frequency and risk factors of convulsions associated with this infection. Thirteen (13.4%) had convulsions, three of whom had additional features suggestive of encephalopathy. Clinical and laboratory data were compared between patients with and without convulsions to define the risk factors for the development of seizures. A high peak temperature and high band forms in excess of 10% of the differential white cell count were significant risk factors. Age, sex, family history of febrile seizure or epilepsy, and the Shigella strain were not significant risk factors.published_or_final_versio

Quantum-state transfer in staggered coupled-cavity arrays

We consider a coupled-cavity array, where each cavity interacts with an atom under the rotating-wave approximation. For a staggered pattern of inter-cavity couplings, a pair of field normal modes each bi-localized at the two array ends arise. A rich structure of dynamical regimes can hence be addressed depending on which resonance condition between the atom and field modes is set. We show that this can be harnessed to carry out high-fidelity quantum-state transfer (QST) of photonic, atomic or polaritonic states. Moreover, by partitioning the array into coupled modules of smaller length, the QST time can be substantially shortened without significantly affecting the fidelity

A critical investigation into the way in which art works demonstrate and contribute to the construction and changing perceptions of national identity in Australia as reflected in the public collections and institutions responsible for collecting and displaying these art works

University of Technology, Sydney. Faculty of Arts and Social Sciences.This thesis discusses the means by which the collection and exhibition of art works, primarily by Australian public collections and institutions, reflect and construct national identity, whether consciously or unconsciously. Cultural history and ‘national identity’ have become areas of particular interest in the available literature as there has been a significant re-evaluation of Australian history in recognition of the fact that a single linear account of history no longer provides an accurate version of the Australian story. This shift has been largely due to societal and political changes in the Australian communities which have facilitate the recognition of diverse groups and the telling of their own stories. This account looks at five major areas of interest – the role of museums, landscape, portraiture, Indigenous art and contemporary art in Australia. Art museums, their acquisition, exhibiting and publication policies and practices, clearly contribute in some formative way, to the images and dialogues around how Australians see themselves domestically and internationally, and to the image projected overseas through the visual arts. Critical and public responses have not always been positive, especially from some of the more conservative commentators, despite the best attempts of art-practitioners and advocates

Optimization of Transparent Electrode Processing Conditions for Bulk Heterojunction Solar Cells

In this work, semi-transparent inverted polymer solar cells with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate; PEDOT:PSS) top electrodes were fabricated by spin-coating process. Poly(3-hexylthiophene; P3HT):[6,6]-phenyl C 61 -butyric acid methyl ester (PCBM) was used as a model material combination for a bulk heterojunction solar cell, because this material combination has been frequently studied, and its properties and performance have been well established. For enhancing the wetting of P3HT:PCBM blend film, different plasma etching conditions were tried. In addition, different high boiling point organic additives were tried to enhance the conductivity of PEDOT:PSS. The performance of solar cells with different fabrication conditions for the top electrode was compared. The best performance was obtained for Ar plasma etching to improve wetting of PEDOT:PSS and the addition of ethylene glycol to improve conductivity.published_or_final_versio

Effect of ZnO surface defects on efficiency and stability of ZnO-based perovskite solar cells

ZnO as an alternative electron transport layer (ETL) material for perovskite solar cell applications has drawn increasing research interest due to its comparable energy levels to TiO2, relatively high electron mobility, as well as its feasibility to be processed at low temperatures for potential applications in flexible devices. Nevertheless, ZnO based perovskite devices usually exhibit inferior performance and severe stability drawbacks which are related to the surface defects of ZnO ETL. In this study, to investigate the correlation between ZnO defect composition and resulting device performance, different approaches of preparing ZnO ETL are compared in terms of the perovskite morphology and device performance. In addition, direct manipulations of ZnO surface defects are performed by various surface treatments, and the photovoltaic performance of devices with ZnO ETL subjected to different surface treatments is compared. Surface modification of ZnO ETL by ethanolamine (EA) is demonstrated to efficiently enhance the photovoltaic performance of resulting ZnO based devices. © (2017) COPYRIGHT Societypublished_or_final_versio