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801.
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
802.
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
803.
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
804.
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
805.
806.
Reinert ZE Musselman ED Elcock AH Horne WS 《Chembiochem : a European journal of chemical biology》2012,13(8):1107-1111
PEGged out: Poly(ethylene glycol), a simple biocompatible polymer, can replace natural loop segments in a 56-residue protein domain with a well-defined tertiary structure. Biophysical characterization of chimeras of the protein GB1 coupled with molecular dynamics simulations show that PEG enhances local backbone torsional freedom without compromising the overall protein fold or function. 相似文献
807.
Mercatelli L Sani E Giannini A Di Ninni P Martelli F Zaccanti G 《Nanoscale research letters》2012,7(1):96
The full characterization of the optical properties of nanofluids consisting of single-wall carbon nanohorns of different
morphologies in aqueous suspensions is carried out using a novel spectrophotometric technique. Information on the nanofluid
scattering and absorption spectral characteristics is obtained by analyzing the data within the single scattering theory and
validating the method by comparison with previous monochromatic measurements performed with a different technique. The high
absorption coefficient measured joint to the very low scattering albedo opens promising application perspectives for single-wall
carbon nanohorn-based fluid or solid suspensions. The proposed approximate approach can be extended also to other low-scattering
turbid media. 相似文献
808.
High-quality single-crystalline Ge nanowires with electrical properties comparable to those of bulk Ge have been synthesized by vapor-liquid-solid growth using Au growth seeds on SiO(2)/Si(100) substrates and evaporation from solid Ge powder in a low-temperature process at crucible temperatures down to 700?°C. High nanowire growth rates at these low source temperatures have been identified as being due to sublimation of GeO from substantial amounts of GeO(2) on the powder. The Ge nanowire synthesis from GeO is highly selective at our substrate temperatures (420-500?°C), i.e., occurs only on Au vapor-liquid-solid growth seeds. For growth of nanowires of 10-20?μm length on Au particles, an upper bound of 0.5?nm Ge deposition was determined in areas of bare SiO(2)/Si substrate without Au nanoparticles. 相似文献
809.
Youssef JJ Brown CD Friedman EA 《Hemodialysis international. International Symposium on Home Hemodialysis》2008,12(1):30-33
A 76-year-old woman hemodialysis patient was hospitalized for community-acquired pneumonia complicating chronic obstructive pulmonary disease. End-stage renal disease secondary to hypertension had been diagnosed at the age of 64 for which the patient was initiated on maintenance hemodialysis. Then, she received a deceased donor kidney transplant at the age of 68 that succumbed to chronic rejection 4 years later when she was restarted on hemodialysis. Hemodialysis was performed via a right subclavian vein double lumen catheter for 2 months when a right brachio-axillary graft was inserted. Severe venous congestion, swelling, and nipple tenderness of her right breast noted on admission had been increasing for 6 weeks before hospital admission. No arm swelling was evident. Initial management of the patient's pneumonia and chronic obstructive pulmonary disease consisted of intravenous ceftriaxone and albuterol inhaler to which intravenous oxacillin (1 g q 6 hr) was added for presumed right mastitis. Radiological work-up for masses and malignancies was negative. An angiogram of the right upper extremity detected stenosis of the dialysis access graft at its anastomosis with the axillary vein. Angioplasty of the stenosis was performed without incident or evidence of central vein stenosis. Rapid resolution over 10 days of the unilateral breast congestion followed without complication. 相似文献
810.
Genotoxicity screening sensors that measure DNA damage from metabolism of arylamines were developed and evaluated. The sensors feature ultrathin films containing DNA and N-acetyltransferase (NAT) on pyrolytic graphite (PG) electrodes. NAT in the film catalyzed the conversion of the arylamine 2-aminofluorene (2-AF) to 2-acetylaminofluorene (2-AAF) by acetyl coenzyme A (AcCoA) dependent N-acetylation, as verified by liquid chromatography. DNA damage in the films from exposure to reactive 2-AF metabolites was measured subsequent to the enzyme reaction using catalytic voltammetric oxidation with Ru(bpy)32+. Square wave voltammetric (SWV) peaks increased with enzyme reaction time, and relative DNA damage rates at pH 5.8 were measured within 2 min. Control incubations of DNA/NAT films without AcCoA gave no significant sensor response. CapLC-MS/MS analysis of 2-AAF/DNA reaction products was consistent with 2-AF-guanine adducts formed in the films. DNA damage occurred more rapidly under weakly acidic conditions (pH 5.5-5.8) than at neutral pH, suggesting that genotoxicity from arylamine metabolism by NAT could be more significant in slightly acidic environments. 相似文献