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1.
Bernette Maria Oosterlaken Heiner Friedrich Gijsbertus de With 《Microscopy research and technique》2022,85(1):412-417
Transmission electron microscopy (TEM) is an important analysis technique to visualize (bio)macromolecules and their assemblies, including collagen fibers. Many protocols for TEM sample preparation of collagen involve one or more washing steps to remove excess salts from the dispersion that could hamper analysis when dried on a TEM grid. Such protocols are not standardized and washing times as well as washing solvents vary from procedure to procedure, with each research group typically having their own protocol. Here, we investigate the influence of washing with water, ethanol, but also methanol and 2-propanol, for both mineralized and unmineralized collagen samples via a protocol based on centrifugation. Washing with water maintains the hydrated collagen structure and the characteristic banding pattern can be clearly observed. Conversely, washing with ethanol results in dehydration of the fibrils, often leading to aggregation of the fibers and a less obvious banding pattern, already within 1 min of ethanol exposure. As we show, this process is fully reversible. Similar observations were made for methanol and propanol. Based on these results, a standardized washing protocol for collagenous samples is proposed. 相似文献
2.
Gökelma Mertol Einarsrud Kristian Etienne Tranell Gabriella Friedrich Bernd 《Metallurgical and Materials Transactions B》2020,51(2):850-860
Metallurgical and Materials Transactions B - The quality requirements of aluminum products are steadily increasing, and the presence of non-metallic inclusions have a large impact on the quality of... 相似文献
3.
Kazuo Tsubota Stephen C. Pflugfelder Zuguo Liu Christophe Baudouin Hyo Myung Kim Elisabeth M. Messmer Friedrich Kruse Lingyi Liang Jimena Tatiana Carreno-Galeano Maurizio Rolando Norihiko Yokoi Shigeru Kinoshita Reza Dana 《International journal of molecular sciences》2020,21(23)
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint. 相似文献
4.
AbstractMulti-agent systems need to communicate to coordinate a shared task. We show that a recurrent neural network (RNN) can learn a communication protocol for coordination, even if the actions to coordinate are performed steps after the communication phase. We show that a separation of tasks with different temporal scale is necessary for successful learning. We contribute a hierarchical deep reinforcement learning model for multi-agent systems that separates the communication and coordination task from the action picking through a hierarchical policy. We further on show, that a separation of concerns in communication is beneficial but not necessary. As a testbed, we propose the Dungeon Lever Game and we extend the Differentiable Inter-Agent Learning (DIAL) framework. We present and compare results from different model variations on the Dungeon Lever Game. 相似文献
5.
H.C. Weigele L. Gygax A. Steiner B. Wechsler J.-B. Burla 《Journal of dairy science》2018,101(3):2370-2382
Lameness is one of the most prevalent diseases affecting the welfare of cows in modern dairy production. Lameness leads to behavioral changes in severely lame cows, which have been investigated in much detail. For early detection of lameness, knowledge of the effects of moderate lameness on cow behavior is crucial. Therefore, the behavior of nonlame and moderately lame cows was compared on 17 Swiss dairy farms. On each farm, 5 to 11 nonlame (locomotion score 1 of 5) and 2 to 7 moderately lame (locomotion score 3 of 5) cows were selected for data collection in two 48-h periods (A, B) separated by an interval of 6 to 10 wk. Based on visual locomotion scoring, 142 nonlame and 66 moderately lame cows were examined in period A and 128 nonlame and 53 moderately lame cows in period B. Between these 2 periods, the cows underwent corrective hoof trimming. Lying behavior, locomotor activity, and neck activity were recorded by accelerometers (MSR145 data logger, MSR Electronics GmbH, Seuzach, Switzerland), and feeding and rumination behaviors by noseband sensors (RumiWatch halter, ITIN + HOCH GmbH, Liestal, Switzerland). Furthermore, visits to the brush and the concentrate feeder, and the milking order position were recorded. In comparison with nonlame cows, moderately lame cows had a longer lying duration, a longer average lying bout duration, and a greater lateral asymmetry in lying duration. Average locomotor activity, locomotor activity during 1 h after feed delivery or push-ups, and average neck activity were lower in moderately lame cows. Eating time and the number of eating chews (jaw movements) were reduced in moderately lame compared with nonlame cows, whereas no effect of moderate lameness was evident for ruminating time, number of ruminating chews and boluses, and average number of ruminating chews per bolus. Moderately lame cows visited the concentrate feeder and the brush less frequently, and they were further back in the milking order compared with nonlame cows. In conclusion, nonlame and moderately lame cows differed in a biologically relevant way in many of the behavioral variables investigated in this study. Therefore, the use of these behavioral changes seems to be promising to develop a tool for early lameness detection. 相似文献
6.
Mitochondrial and cytosolic branched-chain amino acid transaminases from yeast, homologs of the myc oncogene-regulated Eca39 protein 总被引:1,自引:0,他引:1
G Kispal H Steiner DA Court B Rolinski R Lill 《Canadian Metallurgical Quarterly》1996,271(40):24458-24464
We have isolated a high copy suppressor of a temperature-sensitive mutation in ATM1, which codes for an ABC transporter of Saccharomyces cerevisiae mitochondria. The suppressor, termed BAT1, encodes a protein of 393 amino acid residues with an NH2-terminal extension that directs Bat1p to the mitochondrial matrix. A highly homologous protein, Bat2p, of 376 amino acid residues was found in the cytosol. Both Bat proteins show striking similarity to the mammalian protein Eca39, which is one of the few known targets of the myc oncogene. Deletion of a single BAT gene did not impair growth of yeast cells. In contrast, deletion of both genes resulted in an auxotrophy for branched-chain amino acids (Ile, Leu, and Val) and in a severe growth reduction on glucose-containing media, even after supply of these amino acids. Mitochondria and cytosol isolated from bat1 and bat2 deletion mutants, respectively, contained largely reduced activities for the conversion of branched-chain 2-ketoacids to their corresponding amino acids. Thus, the Bat proteins represent the first known isoforms of yeast branched-chain amino acid transaminases. The severe growth defect of the double deletion mutant observed even in the presence of branched-chain amino acids suggests that the Bat proteins, in addition to the supply of these amino acids, perform another important function in the cell. 相似文献
7.
Osvath P. Zingales G. Bartnikas R. Salama M.M.A. von Glahn P. Gulski E. Quinlan J. Steiner J.P. Stone G.C. 《Dielectrics and Electrical Insulation, IEEE Transactions on》1995,2(4):685-699
Some of the more salient aspects of the digital processing technology of PD signals are examined. Most of the efforts in this field are concentrated on the application of digital analyzers for pulse height analysis, pattern recognition and identification of the physical phenomena. It is demonstrated that errors in the signal processing unit can lead to dominant mistakes in the interpretation of the test results 相似文献
8.
Timothy Thomasma Kurt Hilbrecht 《International Journal of Flexible Manufacturing Systems》1991,3(3-4):231-250
Good methods are needed to specify, test, and debug material-handling control logic. This article surveys a number of representative methods for defining and describing control algorithms for programmable material-handling equipment used in flexible manufacturing systems. The methods are evaluated with regard to their suitability for communication between people and as bases for interfaces to automatic program generators. It is concluded that no single method is entirely satisfactory. Three methods (position diagrams, function block diagrams, and operation networks) have potential to be combined into an effective hybrid approach that minimizes the need for the user to switch between various conceptual models. 相似文献
9.
J. J. Hoetjer und F. Koerts 《Holz als Roh- und Werkstoff》1941,4(1):391-393
Zusammenfassung In Zusammenarbeit von MCN und DSM Holland wurde in den beiden letzten Jahren ein Bestimmungsverfahren ausgearbeitet. Unter
Berücksichtigung des Beladungsgrades und der Luftwechselzahl soll dieses Verfahren zur genauen Erfassung des Formaldehydgehaltes
in der Raumluft von Wohnr?umen (Klimar?umen) führen. Das hier als MCN-Test bezeichnete Verfahren, das sich als für diesen
Zweck geeignet erwiesen hat, wird n?her erl?utert.
Method for determining formaldehyde release from particleboard as related to the concentration of the ambient air
During the past years a method for the determination of formaldehyde release from particleboard has been developed in co-operation of MCN and DSM Holland. Considering the loading factor and the air exchange rate this method shall lead to an exact measurement of formaldehyde content in ambient air of rooms (climate chambers). The method (MCN-test) which proved to be suited for this purpose is explained in detail in this paper.相似文献
10.
M. Pleißner M. Schütz A. Behre und A. Scholl 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1911,22(5):316-327
Ohne Zusammenfassung 相似文献