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811.
812.
For nearly all pigs slaughtered in the EU, the lean meat content is assessed on-line at the slaughter line. The assessment is made indirectly by an instrument performing a number of informative measurements including the thickness of back fat as one of the most important and common measurements. Several types of instruments are used for making the measurements. The quality of the calibration (the prediction ability) has to be approved by the EU Commission. However, the maintenance of instruments, training of operators, working conditions and other factors influencing the routine are quite as important for the accuracy as the calibration. As a part of an EU funded project, partners representing thirteen European countries have investigated the instruments used in their countries focusing on the precision of indirect measurements. The preconditions have differed considerably between the countries resulting in a wide range of estimates of the repeatability and the reproducibility (precision) of fat and muscle thickness. Totally, there have been three different types of manual instruments - invasive probe instruments from three manufacturers, non-invasive ultrasound and callipers. Furthermore, the precision of two automatic instruments with respect to lean meat content has partly been estimated. Even though neither the aim nor the design of the experiments was set for a direct comparison between different instruments, none of them seemed to deviate notably from the others with respect to the precision of fat thickness. In this study, the only investigated influencing factors were the variations in operators and copies of instruments. Generally, the variations between operators were more important than the variation between copies of the same type of instrument. 相似文献
813.
Waxman E 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2007,365(1854):1323-1334
The construction of large-volume detectors of high energy, greater than 1TeV, neutrinos is mainly driven by the search for extragalactic neutrino sources. The existence of such sources is implied by the observations of ultra-high-energy, greater than or equal to 1019eV, cosmic rays, the origin of which is a mystery. In this lecture, I briefly discuss the expected extragalactic neutrino signal and the current state of the experimental efforts. Neutrino emission from gamma-ray bursts (GRBs), which are probably sources of both high-energy protons and neutrinos, is discussed in some detail. The detection of the predicted GRB neutrino signal, which may become possible in the coming few years, will allow one to identify the sources of ultra-high-energy cosmic rays and to resolve open questions related to the underlying physics of GRB models. Moreover, detection of GRB neutrinos will allow one to test for neutrino properties (e.g. flavour oscillations and coupling to gravity) with an accuracy many orders of magnitude better than is currently possible. 相似文献
814.
815.
Wyrick J Kim DH Sun D Cheng Z Lu W Zhu Y Berland K Kim YS Rotenberg E Luo M Hyldgaard P Einstein TL Bartels L 《Nano letters》2011,11(7):2944-2948
Anthraquinone self-assembles on Cu(111) into a giant honeycomb network with exactly three molecules on each side. Here we propose that the exceptional degree of order achieved in this system can be explained as a consequence of the confinement of substrate electrons in the pores, with the pore size tailored so that the confined electrons can adopt a noble-gas-like two-dimensional quasi-atom configuration with two filled shells. Formation of identical pores in a related adsorption system (at different overall periodicity due to the different molecule size) corroborates this concept. A combination of photoemission spectroscopy with density functional theory computations (including van der Waals interactions) of adsorbate-substrate interactions allows quantum mechanical modeling of the spectra of the resultant quasi-atoms and their energetics. 相似文献
816.
Vlaisavljevich E Janka LP Ong KG Rajachar RM 《IEEE transactions on bio-medical engineering》2011,58(3):698-704
Interfacial fibrosis is known to dramatically decrease the lifespan, stability, and function of biomedical implants and bone-anchored prosthetics. Bioactive coatings aimed at mitigating fibrous adhesions are one of the approaches to alleviate the problem. In this paper, we are developing a bioactive coating based upon a magnetoelastic (ME) material that vibrates in response to an ac magnetic field. In order to establish these coatings for this purpose, the ME material was first rendered bioactive through the sequential addition of polyurethane and chitosan thin films. Indirect live/dead assays were performed showing increased cell viability for polyurethane and chitosan-coated sensors compared to the uncoated controls. Direct adhesion experiments were performed to test the response of fibroblasts cultured on static and vibrated ME materials. Results showed cells adherent to static but not vibrated coatings. Detached cells showed no viability loss compared to controls. The finding that submicrometer ME vibrations can prevent cell adhesion in vitro without inducing cell death suggests the potential of these coatings to effectively control interfacial fibrosis. Future work will address the effect of vibrations on cell morphology and local gene expression in vitro, as well as fibrous tissue formation in vivo. 相似文献
817.
Cover Picture: A Unified Sensor Architecture for Isothermal Detection of Double‐Stranded DNA,Oligonucleotides, and Small Molecules (ChemBioChem 5/2015) 下载免费PDF全文
818.
Eli Cohen 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1982,175(4):258-261
Summary Like many natural products, citrus juice is affected by many factors, such as climatic, seasonal, agrotechnical etc. The seasonal effects cause several problems in quality control. Almost all statistical techniques for quality control of citrus juice suffer from the same problem, namely they are applicable only to samples obtained under similar conditions to those initially taken, and thus avoiding the seasonal variability.
This work was supported by the State of Israel, Ministry of Industry and Trade, Food Division. The paper presents the opinions of the author and not necessarily that of the Ministry 相似文献
Jahreszeitliche Schwankungen von Citrussaft-Inhaltsstoffen und ihr Einfluß auf die Qualitätskontrolle von Citrussäften
Zusammenfassung Wie viele Naturprodukte wird Citrussaft durch verschiedene Faktoren wie Klima, Jahreszeit, gartenbauliche Methoden beeinflußt. Die jahreszeitlichen Einflüsse verursachen ernste Probleme bei der Qualitätskontrolle des Citrussaftes. Fast alle statistischen Techniken zur Qualitätskontrolle von Citrussaft stehen vor dem gleichen Problem, nämlich daß sie sich nur für Proben eignen, die unter gleichen Bedingungen wie das ursprüngliche Muster entnommen wurden und so jahreszeitliche Schwankungen ausgeschlossen werden.
This work was supported by the State of Israel, Ministry of Industry and Trade, Food Division. The paper presents the opinions of the author and not necessarily that of the Ministry 相似文献
819.
Comparative study by computed radiography,histology, and scanning electron microscopy of the articular cartilage of normal goats and in chronic infection with caprine arthritis‐encephalitis virus 下载免费PDF全文
Videlina Rodrigues de Sousa Francisco das Chagas Araújo Sousa Osmar Ferreira da Silva Filho Rose Eli Grassi Rici Anaemilia das Neves Diniz Laécio da Silva Moura Jacyara de Jesus Rosa Pereira Alves Antônio de Sousa Júnior Maria Angélica Miglino João Macedo de Sousa Felipe de Jesus Moraes Junior Flávio Ribeiro Alves 《Microscopy research and technique》2014,77(1):11-16
In the northeast of Brazil, caprine arthritis‐encephalitis (CAE) is one of the key reasons for herd productivity decreasing that result in considerable economic losses. A comparative study was carried out using computed radiography (CR), histological analysis (HA), and scanning electronic microscopy (SEM) of the joints of CAE infected and normal goats. Humerus head surface of positive animals presented reduced joint space, increased bone density, and signs of degenerative joint disease (DJD). The carpal joint presented no morphological alterations in CR in any of the animals studied. Tarsus joint was the most affected, characterized by severe DJD, absence of joint space, increased periarticular soft tissue density, edema, and bone sclerosis. Histological analysis showed chronic tissue lesions, complete loss of the surface zone, absence of proteoglycans in the transition and radial zones and destruction of the cartilage surface in the CAE positive animals. Analysis by SEM showed ulcerated lesions with irregular and folded patterns on the joint surface that distinguished the limits between areas of normal and affected cartilage. The morphological study of the joints of normal and CAE positive goats deepened understanding of the alteration in the tissue bioarchitecture of the most affected joints. The SEM finding sustained previous histological reports, similar to those found for rheumatoid arthritis, suggesting that the goat infected with CAE can be considered as a potential model for research in this area. Microsc. Res. Tech. 77:11–16, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
820.
介绍了hfe≥12000的两级功率达林顿器件的设计方法及关键技术,并对在10A比1mA的条件下实现低饱和压降的几项措施作了较详细的讨论。 相似文献