24 research outputs found

    Perturbation theory of the space-time non-commutative real scalar field theories

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    The perturbative framework of the space-time non-commutative real scalar field theory is formulated, based on the unitary S-matrix. Unitarity of the S-matrix is explicitly checked order by order using the Heisenberg picture of Lagrangian formalism of the second quantized operators, with the emphasis of the so-called minimal realization of the time-ordering step function and of the importance of the \star-time ordering. The Feynman rule is established and is presented using ϕ4\phi^4 scalar field theory. It is shown that the divergence structure of space-time non-commutative theory is the same as the one of space-space non-commutative theory, while there is no UV-IR mixing problem in this space-time non-commutative theory.Comment: Latex 26 pages, notations modified, add reference

    Soil-transmitted helminthiasis - challenges with discovery of novel anthelmintics

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    Soil‐transmitted helminths (STHs) are responsible for many millions of disability‐adjusted life‐years (DALYs) in the developing world; however, there is no research focused directly on development of new therapies, due to the high costs of research and development. Historically, anthelmintics for human helminthiases have been leveraged from the animal health industry, where the impact of helminth infections on production in ruminants, plus the health and zoonotic concerns for companion animals has driven significant sales. It is therefore highly probable that the next generation of anthelmintics for control of STHs will be leveraged from research in the animal health industry. A review of the state of the art in anthelmintic patents over the past 10 years highlights that there has been some progress in identifying and optimizing novel anthelmintic classes for management of emerging resistance in ruminants and companion animals. Although investment is low when compared to human health research and development, the animal health industry has been successful in optimizing lead series from pesticide research to animal health, and this is evident with some of the recent patents. Increased collaborative public–private partnerships will be required to help translate these discoveries into therapies for STHs

    Genetic diversity and population structure of Zymoseptoria tritici on bread wheat in Tunisia using SSR markers

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    Septoria tritici blotch (STB) caused by Zymoseptoria tritici is the primary biotic stress for durum wheat production in Tunisia. The present study was aimed to decipher the genetic diversity and population structure of Z. tritici bread wheat isolates; in the northern regions of Tunisia this pathogen infected exclusively bread wheat. A total of 162 single-spore isolates were sampled during the 2015–2016 growing season from nine naturally infected bread wheat fields at four locations in the three main wheat-growing regions in Tunisia, previously reported as hot spots for Septoria disease (Cap Bon, Bizerte, and Beja). Collected isolates were fingerprinted using twelve polymorphic microsatellite markers to assess the genetic diversity and population structure of Z. tritici. All the microsatellite loci were polymorphic and a high genetic diversity was observed within the whole population. The highest Nei’s index value (0.42), Shannon Index (0.84) and private allele numbers (36) were found at the El Haouaria location (Cap Bon region). Furthermore, a moderate genetic differentiation within and among the surveyed locations (73% and 27%) was confirmed by analysis of molecular variance (AMOVA). On the other hand, the STRUCTURE program was shown to be less sensitive in revealing genetic structure especially at low levels of diversity. Thus, information on the genetic structure of the pathogen population collected from bread wheat is useful for designing and implementing durable and effective management strategies

    Efeito anti-helmíntico dos extratos aquosos e etanólicos da Annona squamosa L. (fruta-do-conde) sobre o nematóide Ascaridia galli Anthelmintic effect of aqueous and ethanolic extracts from Annona squamosa L. (sweetsop) on the nematode Ascaridia galli

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    As plantas são fontes importantes de produtos naturais biologicamente ativos. Dentre as plantas usadas na medicina popular a Anonna squamosa conhecida como fruta-do-conde é citada como tendo várias ações medicinais, dentre elas a atividade inseticida e anti-helmíntica. Dentro desta perspectiva, objetivou-se determinar a atividade anti-helmíntica dos extratos aquosos (EA) e etanólicos (EE) das folhas da fruta-do-conde sobre o nematóide de aves Ascaridia galli, in vitro e in vivo. No primeiro, os nematóides foram colocados em placa de Petri contendo diferentes concentrações dos extratos e no segundo foram utilizadas seis galinhas poedeiras por grupo, as quais foram administrados10 mL Kg-1 dos extratos. No teste in vitro o EA da A. squamosa nas concentrações 2,4 e 9,6 mg mL-1 foi capaz de matar 63,33% e 53,33% dos nematóides, respectivamente. O EE não produziu efeito significativo. No teste in vivo, o percentual de eliminação do EA foi de 39% e do EE de 20%. Estes dados sugerem que neste caso a substância responsável pela mortalidade dos parasitos esteja em maior concentração na fração aquosa. Desta maneira, acredita-se que o EA de A. squamosa apresenta uma atividade anti-helmíntica potencial sobre o A. galli.<br>Plants are important sources of biologically active natural products. Among the plants used in popular medicine, Annona squamosa, known as sweetsop, is reported to have several medicinal actions such as insecticidal and anthelmintic activity. Therefore, this study aimed to assess the anthelmintic activity of aqueous (AE) and ethanolic (EE) extracts from sweetsop leaves on the chicken roundworm Ascaridia galli, both in vitro and in vivo. In the former, nematodes were placed on a Petri plate containing different concentrations of the extracts; in the in vivo test, six egg-laying chickens per group received 10 mL Kg-1 of the extracts. In vitro results indicated that A. squamosa AE at the concentrations 2.4 and 9.6 mg mL-1 could kill 63.33% and 53.33% nematodes, respectively. However, EE did not have any significant effect. According to the in vivo test, the elimination percentage for AE was 39% and for EE, 20%. These data suggest that the substance responsible for parasite mortality was present at a higher concentration in the aqueous fraction. Thus, A. squamosa AE is believed to have a potential anthelmintic activity on A. galli

    Electromechanical cardioplasty using a wrapped elasto-conductive epicardial mesh

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    Heart failure remains a major public health concern with a 5-year mortality rate higher than that of most cancers. Myocardial disease in heart failure is frequently accompanied by impairment of the specialized electrical conduction system and myocardium. We introduce an epicardial mesh made of electrically conductive and mechanically elastic material, to resemble the innate cardiac tissue and confer cardiac conduction system function, to enable electromechanical cardioplasty. Our epicardium-like substrate mechanically integrated with the heart and acted as a structural element of cardiac chambers. The epicardial device was designed with elastic properties nearly identical to the epicardial tissue itself and was able to detect electrical signals reliably on the moving rat heart without impeding diastolic function 8 weeks after induced myocardial infarction. Synchronized electrical stimulation over the ventricles by the epicardial mesh with the high conductivity of 11,210 S/cm shortened total ventricular activation time, reduced inherent wall stress, and improved several measures of systolic function including increases of 51% in fractional shortening, ∼90% in radial strain, and 42% in contractility. The epicardial mesh was also capable of delivering an electrical shock to terminate a ventricular tachyarrhythmia in rodents. Electromechanical cardioplasty using an epicardial mesh is a new pathway toward reconstruction of the cardiac tissue and its specialized functions. © 2016, American Association for the Advancement of Science. All rights reserved117331sciescopu
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