Alternatives to antibiotic growth promoters in prevention of diarrhoea in weaned piglets: a review Vondruskova, H.,Vyzkumny Ustav Veterinarniho Lekarstvi, Brno (Czech Republic); Slamova, R.,Vyzkumny Ustav Veterinarniho Lekarstvi, Brno (Czech Republic); Trckova, M.,Vyzkumny Ustav Veterinarniho Lekarstvi, Brno (Czech Republic) ...
Veterinární medicína,
01/2010, Volume:
55, Issue:
5
Journal Article
Peer reviewed
Open access
The weaning time is a crucial period in the management of piglets. The risk of development of post-weaning diarrhoea (PWD) in piglets is high. PWD is the cause of serious economic losses in pig ...herds. Since 2006, the use of antibiotic growth promoters for prevention of diarrhoeal diseases in piglets has been banned. This measure also led to the investigation of alternative suitable feed supplements that would be reasonably efficient in protecting and sustaining animal health and performance. Various natural materials such as probiotics, prebiotics, organic acids, zinc and plant extracts have been tested as effective alternatives to antibiotics. Recently, owing to their high adsorption capacity, research efforts have been conducted on the application of natural clays and clay-based feed supplements. The purpose of this review is to summarize the effect of different alternative components as growth promoters on the health and performance of weaned and growing piglets.
In this paper, bisphenol A epoxy resin (E-51) as A group, Methyl tetrahydrodiphosphonic anhydride (MTHPA) as A curing agent, and acid anhydride crosslinking system epoxy resin samples were prepared. ...By establishing a condensation discharge platform, the surface condensation of epoxy resin was studied by temperature, relative humidity, and filth degree. The influence of hygrothermal corona aging on the surface flashover voltage of epoxy resin in the condensation state was analyzed by static contact Angle, scanning electron microscope, and infrared spectrum. The results showed that with the increase of temperature difference, relative humidity, and fouling degree, the surface condensation quality of epoxy resin also increased, and the temperature difference had the greatest effect on the surface condensation quality. With the increase of aging time, the static contact Angle decreased from 83.8° to 36.7°. At the same time, a large number of cracks appeared on the surface of the material, accompanied by skin shedding, and the surface decomposition and carbonization phenomenon occurred. The decomposition of -COOR group and -C=O group inside epoxy resin is accompanied by the generation of -OH and -COOH groups. The surface flashover characteristics of epoxy resin are positively correlated with the content of water molecules in the air, and the hydrophilic -OH and -COOH groups lead to the degradation of its electrical properties. The research results of this paper can provide reference for the operation and maintenance of switchgear with epoxy resin as the main insulation structure.
Natural and artificial superhydrophobic surfaces are a rapidly growing topic in both academia and industry due to their unique properties and applications. Numerous techniques have been developed to ...characterize the wetting properties of such surfaces, such as the optical contact angle goniometer, force-based methods, and microscopic techniques for visualizing the wetting interface. However, a method that combines nN resolution force measurement with direct observation of the wetting interface on opaque superhydrophobic surfaces is missing. Here, we report a high-sensitivity multimodal force-sensing transparent droplet probe for the characterization of superhydrophobic surfaces that allows simultaneous visualization of the wetting interface and measurement of interaction forces. The probe is composed of a transparent glass cantilever with a droplet probe attached to its end. During the interaction with the sample, the wetting interface is directly imaged through the probe, illuminated with coaxial lighting. The interaction force is simultaneously measured as the deflection of the cantilever-shaped probe. By combining top-view, side-view, and high-resolution force sensing, the probe can reveal force contributions from both surface tension and Laplace pressure, and measure super-repellent surfaces with contact angles near 180 ° with a low experimental uncertainty of 0.5 °.
A detailed account is given of the history, aetiology, biology, epidemiology, detection, geographical distribution, and control of huanglongbing (HLB), a destructive disease of citrus that represents ...a major threat to the world citrus industry, and is slowly invading new citrusgrowing areas. HLB, whose name in Chinese means "yellow dragon disease", was first reported from southern China in 1919 and is now known to occur in next to 40 different Asian, African, Oceanian, South and North American countries. The agent is a phloem-restricted, non cultured, Gram-negative bacterium causing crippling diseases denoted "greening" in South Africa, "mottle leaf" in the Philippines, "dieback" in India, "vein phloem degeneration" in Indonesia. The HLB bacterium belongs to the genus Candidatus Liberibacter, three species of which are currently known, Candidatus Liberibacter asiaticus, occurring in Asian countries and, to a lesser extent, in Brazil and the USA (Florida), Candidatus Liberibacter africanus with its subspecies "capensis", recorded from African countries, and Candidatus Liberibacter americanus present in Brazil. The suggestion is that each liberibacter species has evolved in the continent after which it is named. HLB symptoms are virtually the same wherever the disease occurs. Infected trees show a blotchy mottle condition of the leaves that results in the development of yellow shoots, the early and very characteristic symptom of the disease. Trees are stunted, declining and bear a few, small-sized, and deformed (lop-sided) fruits, that are poorly coloured (greening) and with coloration starting at the peduncular end (colour inversion). HLB can be transmitted by grafting from citrus to citrus and by dodder to periwinkle. The psyllids Trioza erytreae and Diaphorina citri are natural vectors. Two different types of HLB are known: the heat-sensitive African form transmitted by T. erytreae, which develops at temperatures of 22-25°C, and the heat-tolerant Asian form, transmitted by D. citri, which stands temperatures well above 30°C. Although the HLB pathogen can be identified by electron microscopy, other laboratory methods are used for routine detection. ELISA with monoclonal antibodies is not recommended. Better systems are dot blot hybridization with a DNA probe, and various PCR formats (one-step, nested, multiplex) using species-specific primers based on 16S rRNA or rplKAJL-rpoBC operon sequences. Because no curative methods of HLB are available, control is preventive and largely based on inoculum elimination by removal of infected trees and chemical treatments against vectors. Strict quarantine measures must be implemented to impair further international spread of HLB agents and their vectors.
The effects of sex and slaughter age on growth, feed intake, carcass composition and meat quality attributes of musculus longissimus lumborum were investigated in Charolais x Simmental bulls (n = 12) ...and heifers (n = 12) reared and finished under identical management conditions. The animals entered the experiment at similar age (251 days) and were slaughtered at 14 or 18 months of age. Bulls gained more rapidly (P less than 0.001), consumed more dry matter daily (P less than 0.05), and had a higher killing-out proportion (P less than 0.05). The sex x slaughter age interaction was significant for feed conversion ratio, which deteriorated markedly more in heifers than in bulls as slaughter age increased. Bulls produced leaner carcasses with a higher proportion of total meat (P less than 0.001). While bulls contributed to high-priced meat by a higher proportion of meat from the shoulder (P less than 0.01), heifers had higher proportions of meat from the rump and loin (P less than 0.05). Older animals were generally fatter and their carcasses contained lower proportions of high-priced meat (P less than 0.01) and bones (P less than 0.05). Bulls exhibited lower contents of dry matter (P less than 0.001), protein (P less than 0.05) and intramuscular fat (P less than 0.001), and a higher content of collagen (P less than 0.001) in musculus longissimus lumborum than heifers. The meat from heifers was assessed by the sensory panel as more tender and, when aged for 11 days, more acceptable than the meat from bulls. Older animals obtained higher scores for beef flavour intensity (P less than 0.01), tenderness (P less than 0.001), juiciness (P less than 0.05), and overall acceptance (P less than 0.001).
A surface plasmon resonance (SPR) dual-parameter sensor is designed and fabricated. It was electroless plated with silver on the surface of the core of the plastic-clad optical fiber, and a gold film ...was plated near the end face side to produce the double SPR resonance valleys. 4-mercaptophenylboronic acid (4-MPBA) and β-cyclodextrin (β-CD) were coated separately on the surface of silver and gold film. 4-MPBA can selectively recognize the structures of cis-vicinal diols, and thus can capture glucose that contains such structures. β-CD is a class of cyclic oligosaccharides whose unique hydrophilic outer surface and lipophilic central cavity help facilitate the formation of inclusion complexes with cholesterol through multiple interactions. The sensor can detect 0-4 mM glucose and 0-500 nM cholesterol, and it has a linear response in the concentration range of 0-0.1mM glucose and 0-15 nM cholesterol. The sensitivity of glucose and cholesterol concentration of the sensor is 89.6 nm/mM and 0.994 nm/nM respectively. The detection limits for quantifying glucose and cholesterol are1.12μM and 0.1nM, respectively. The experimental results also show that the sensor has good selectivity and stability. The proposed technique can be further applied in medicine, environment, and biology monitoring.
In this paper, we consider the ergodicchannel capacity (ECC) of several generalized fading channels for a mobile user that moves inside a coverage area according to the random waypoint (RWP) mobility ...model. The ECC with RWP mobility provides the average capacity of a mobile receiver taking into account the probability density function (PDF) of the distance between the user and the transmitting antenna, the path loss exponent and the fading channel. It turns out that the ECC in a mobile environment can be written in terms of the corresponding ECC in the static case. Therefore, we use analytical expressions of the ECC of different generalized fading models for the static channel to derive the corresponding analytical expressions for the ECC in the mobile case. Asymptotic expressions, in the high signal-to-noise ratio (SNR) regime, are also provided that quickly converge to the exact ones. Monte Carlo simulation is also used to show the validity of the derived expressions. The analytical exact and asymptotic expressions enable the system designer to quantify the effect of different physical channel and mobility parameters on the attained average capacity of generalized fading channels.
Z -number is an effective model to describe uncertainty in the real world. Under the condition that uncertainty reasoning is an important issue to process information, how to achieve Z -valuation ...uncertainty reasoning is a problem. As a Z -number involves both fuzzy and probabilistic uncertainty, main difficulty in the problem to be solved is accomplishing both two uncertainties' reasoning. In this paper, a novel Z -network model and its associated reasoning algorithm are proposed to overcome the difficulty. Structure of the proposed Z -network that contains three basic structures is directed acyclic graph, and this is similarly with Bayesian network (BN). Process of reasoning algorithm involves two parts: first, Bayesian reasoning is applied to establish an optimization model for probabilistic uncertainty reasoning in a Z -number; second, the arithmetic approach of discrete Z -number on if-then rule and maximum entropy approach are proposed for fuzzy uncertainty reasoning. Z -network is essentially an extended model on the basis of BN and properties of a Z -number for Z -valuation uncertainty reasoning. In application, a novel framework of dependence assessment in human reliability analysis is proposed based on Z -network, and a case study demonstrates its effectiveness.
Spoilage fungi are ubiquitous contaminants of cereals, pre- and post-harvest. These fungi can produce a wide range of secondary metabolites under ecological conditions which are conducive for growth. ...However, some of these secondary metabolites are toxic and have a significant impact if they enter the production and animal food chains. Prevention of mycotoxin contamination of feed and food raw materials is now considered more important than subsequent cure. The key ecological determinants pre- and post-harvest are water availability and temperature (climate). Accurate information is therefore needed on the impact of an association between these key factors, and it is necessary to understand which are marginal and which critical for germination and toxin production. There have only been a few studies where attempts have been made to integrate the available information on these factors in relation to different raw materials for feed and food processing, especially cereals. This review will examine the available information on the main climatic factors, i.e., water availability and temperature affecting mycotoxin production such as, aflatoxins, ochratoxins, fumonisins, zearalenone, deoxynivalenol and citrinin. This information is crucial for accurately focusing and monitoring key critical control points in the feed and food chain to optimise prevention strategies.
Z-Differential Equations Mazandarani, Mehran; Zhao, Yi
IEEE transactions on fuzzy systems,
2020-March, 2020-3-00, Volume:
28, Issue:
3
Journal Article
Peer reviewed
This paper is devoted to make a framework for studying a class of uncertain differential equations called Z-differential equations. In order to achieve the purpose, we first introduce four basic ...operations on Z + -numbers based on semigranular function. Then, the limit and continuity concepts of a Z-number-valued function are given, under a definition of a metric on the space of Z + -numbers. Moreover, the concepts of Z-differentiability, Z-integral, and Z-Laplace transform of a Z-number-valued function are introduced. In addition, by giving some theories proved in this paper, a basis for calculus-Z-calculus-is established. We further give theories based on which existence and uniqueness of Zdifferential equations are investigated. A conceptual unity between Z-differential equations and Z + -numbers is also shown. The conceptual unity demonstrates that a Z-differential equation may be expressed as a bimodal differential equation combining a fuzzy differential equation (FDE) and a random differential equation. Moreover, the concept of a bimodal cut called (s, μ)-cut is introduced and its relation to other new concepts such as acceptable time and acceptable information area is explained. Using an example, the application of Z-differential equations in medicine is clarified. It is demonstrated that Z-differential equations outperform FDEs in making a decision under uncertainty.
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