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1.
2.
Cardiodilatin (CDD)/atrial natriuretic peptide (ANP) is a 28-amino acid peptide hormone known to be synthesized in the heart of a large number of different vertebrates. It plays an important role in the regulation of blood pressure and natriuresis/diuresis. Since the cardiovascular system of the horse has to meet the highest requirements concerning its physiological performance, we intended to characterize the cardiodilatin/atrial natriuretic peptide system of this species. By means of immunohistochemistry and immunoelectron microscopy, we precisely identified auricular cardiocytes as the loci of CDD/ANP synthesis. Using aortic smooth muscle relaxation assay and CDD/ANP-ELISA, we succeeded in isolating the biologically active prohormone. We subsequently cloned the equine cDNA of the CDD/ANP precursor protein and deduced its primary sequence. The entire precursor protein is in good agreement with the CDD/ANP prohormones of other mammals. The deduced theoretical average Mr of equine CDD/ANP-1-126 is 13,764, corresponding to the molecular weight of purified peptide determined by ESI-MS. Our findings suggest that equine CDD/ANP is produced in auricular cardiocytes and the predominant storage form of CDD/ANP in the auricle is the prohormone CDD/ANP-1-126. 相似文献
3.
Pontus Johnson Johan Ullberg Markus Buschle Ulrik Franke Khurram Shahzad 《Information Systems and E-Business Management》2014,12(4):595-622
In the design phase of business and IT system development, it is desirable to predict the properties of the system-to-be. A number of formalisms to assess qualities such as performance, reliability and security have therefore previously been proposed. However, existing prediction systems do not allow the modeler to express uncertainty with respect to the design of the considered system. Yet, in contemporary business, the high rate of change in the environment leads to uncertainties about present and future characteristics of the system, so significant that ignoring them becomes problematic. In this paper, we propose a formalism, the Predictive, Probabilistic Architecture Modeling Framework (P2AMF), capable of advanced and probabilistically sound reasoning about business and IT architecture models, given in the form of Unified Modeling Language class and object diagrams. The proposed formalism is based on the Object Constraint Language (OCL). To OCL, P2AMF adds a probabilistic inference mechanism. The paper introduces P2AMF, describes its use for system property prediction and assessment and proposes an algorithm for probabilistic inference. 相似文献
4.
Morten Nobel-Jørgensen Niels Aage Asger Nyman Christiansen Takeo Igarashi J. Andreas Bærentzen Ole Sigmund 《Structural and Multidisciplinary Optimization》2015,51(6):1385-1391
This educational paper describes the implementation aspects, user interface design considerations and workflow potential of the recently published TopOpt 3D App. The app solves the standard minimum compliance problem in 3D and allows the user to change design settings interactively at any point in time during the optimization. Apart from its educational nature, the app may point towards future ways of performing industrial design. Instead of the usual geometrize, then model and optimize approach, the geometry now automatically adapts to the varying boundary and loading conditions. The app is freely available for iOS at Apple’s App Store and at http://www.topopt.dtu.dk/TopOpt3D for Windows and OSX. 相似文献
5.
Heikki Srkel Jari Takatalo Patrick May Mikko Laakso Gte Nyman 《International journal of human-computer studies》2009,67(9):787-799
Human movement in virtual environments (VEs) is a largely unstudied area, and there are no well-established methods of measuring it in VEs. Consequently, it is unclear how movement affects the experiential side of VEs. We introduce a novel method of measuring and modelling human movement. A specific information entropy-based modelling method enabled us to identify different movement patterns and analyse the experiential components related to them. The data was collected by registering the movement patterns of 68 participants who were in a virtual house doing a search task. The experiential side of the VE was measured with the Experimental Virtual Environment Questionnaire (EVEQ). Four movement patterns were identified. In addition, fluent movement in VEs was related to a high sense of presence. Moreover, the participants who moved fluently in the environment assessed their skills high. The results show how movement is related the way in which people experience the VE. The movement analysis method introduced here is applicable to other related research areas as well. 相似文献
6.
L. Ekman A.-K. Nyman H. Landin U. Magnusson K. Persson Waller 《Journal of dairy science》2018,101(1):556-571
Udder cleft dermatitis (UCD) is an inflammatory skin condition affecting the anterior parts of the udder of dairy cows. The lesions may present as mild or severe skin lesions and have been associated with mastitis and digital dermatitis. The full etiology and pathogenesis are not understood and no large-scale studies have investigated prevalence and risk factors. Therefore, the main objectives of the study were to investigate the prevalence of mild and severe UCD in Swedish dairy herds and to identify risk factors associated with such lesions. We also wanted to investigate risk factors for all cases of UCD and to determine whether UCD increases the risk for mastitis and culling. A random sample of 100 freestall dairy herds were included in the study, and each herd was visited once. Cows were registered as having no, mild, or severe UCD. Additional cow and herd data were obtained via observations, interviews, and the Swedish Official Milk Recording Scheme. The data were analyzed using logistic regression models to identify risk factors for mild and severe UCD. In total, data from 3,479 cows in 99 herds were analyzed. The prevalence of mild and severe UCD was 19 and 9%, respectively. Lesions were found in 98 of 99 herds but the within-herd prevalence of mild (0–43%) and severe (0–33%) UCD varied notably between herds. Breed (Swedish Red compared with Swedish Holstein), certain udder conformation traits, and higher parity were risk factors associated with increased risk of UCD. In addition, cows with hock lesions and cows in herds with high incidence of culling due to hoof and leg diseases had a higher risk for mild UCD. More days in milk and high milk yield were cow-related risk factors associated with severe UCD. Three housing-related factors (shorter cubicles, mattress as cubicle base, and cubicles installed before 2001 compared with 2001–2005), a high incidence of veterinary-treated clinical mastitis and culling due to udder diseases, and a low incidence of culling of first-parity cows in early lactation were herd-related risk factors associated with increased risk for severe UCD. In addition, cows in herds with a high proportion of heifers older than 17 mo that were not inseminated were associated with lower risk of all UCD. Finally, UCD was not associated with the outcomes milk somatic cell count, veterinary-treated clinical mastitis, or culling in the multivariable analyses. The etiology of UCD is most likely multifactorial, involving udder conformation traits and other cow-related risk factors as well as herd-related risk factors. The high prevalence of severe UCD lesions in Swedish dairy cows emphasizes the need for preventive measures and efficient treatments. 相似文献
7.
Ulrik Jennische 《Urban Forum》2012,23(4):467-481
Based on anthropological fieldwork in the central market and taxi station of Koforidua, Ghana, this paper aims to improve our understanding of the social dynamics in the informal economy of a Ghanaian small town in relation to state policies. It strives to describe the way processes of formalization and informalization may coexist and interact during the implementation of the recent National Health Insurance Scheme (NHIS) . The ethnographic approach helps us to better understand how attitudes on NHIS are formed and the way information and values are disseminated. Closely examining the social infrastructure of this setting contributes further to this understanding. In the marketplace, it is important to develop networks of personal relations with fellow traders, customers, and suppliers. At the taxi station, on the other hand, the most important strategy is to join the powerful local union. These strategies are ways for actors to gain security and protection against economic vulnerability in a competitive liberalized economy. In this regard, the NHIS has also provided opportunities for actors. While the NHIS is a way for the state to increase control over the informal economy, and gradually formalizing it, it simultaneously indirectly reinforces and confirms the existing informal strategies of networking. 相似文献
8.
Laboratory experiments have been conducted to elucidate the degradation of alpha-methylnaphthalene in lake sediments using an advanced oxidation process (AOP) employing peroxy-acids as oxidizing agents. Abiotic degradation of alpha-methylnaphthalene was observed in sediment samples exposed to a 1:1:1 v/v/v mixture of water/organic acid/hydrogen peroxide solution. Sediment samples were collected from Lake Macatawa (Holland, MI) and ranged in total organic carbon content from 2.1% (sandy sediment sample III) to 12.8% (silty-clay sediment sample I) and surface area, which ranged from 3.2m(2)/g (sandy sediment sample III) to 22.0m(2)/g (silty-clay sediment sample I). Analytical measurements performed by gas chromatography revealed varied rates of degradation, depending on the type of acid and the characteristics of the sediment sample. Within 24h, alpha-methylnaphthalene was reduced to 70% and 100% of its original concentration when propionic acid and acetic acid were used as the organic acids, respectively. The formation of products was explored using a gas chromatograph equipped with a mass spectrometer and indicated mainly the formation of lower molecular weight compounds, such as alkyl chains. This AOP method of PAH degradation in sediment/liquid slurry was fast acting and products were most likely biodegradable. 相似文献
9.
AK Lundgren L Sennerby D Lundgren A Taylor J Gottlow S Nyman 《Canadian Metallurgical Quarterly》1997,8(2):82-89
The aim of the present investigation was to compare the effect of using autologous bone particles covered with a bioresorbable matrix barrier with the use of bone particles alone on bone augmentation at titanium implants installed in the rabbit tibia. Two Br?nemark System implants, one in each tibia, were inserted in each of 9 rabbits in such a way that 5 threads were not covered with bone. Autologous bone particles were harvested from the skull and placed over the exposed implant surfaces on each tibia. The bone graft on one tibia was covered with a Guidor Matrix Barrier, while the bone graft on the other tibia served as a control. After a healing period of 12 weeks, the animals were sacrificed and specimens taken for histomorphometrical analyses. The analyses showed that a significantly larger volume of augmented bone tissue had formed at the test sites. There were, however, no differences in the amount of mineralized bone. In fact, the difference in tissue volume was due to an increased amount of bone marrow at the test sites. The degree of mineralized bone to implant contact as well as the degree of mineralized bone within the threads at the test implants were similar to that at the controls. In conclusion, it was found that the coverage of particulate autologous bone grafts with a bioresorbable barrier resulted in a larger volume of augmented bone than the use of bone grafts not covered with a barrier. 相似文献
10.
The content of low molecular weight carbohydrates (LMWC, glucose, fructose, sucrose, raffinose, stachyose and verbascose) was investigated in 29 cultivars of vining peas after blanching and freezing. The peas were harvested at about the same degree of ripeness. There was a positive correlation between the amount of raffinose, stachyose and sorbitol, while a high content of verbascose only could be seen when there was a low content of these sugars. High concentrations of sucrose were generally associated with high concentrations of glucose and fructose. Samples from 1999 had a significantly (p < 0.001) higher content of raffinose, stachyose and sorbitol and lower of verbascose, probably because of the drier and warmer summer that year compared with 1998. Furthermore, medium and late maturing cultivars contained larger amounts of raffinose, stachyose and sorbitol than early cultivars, possibly due to the fact that these cultivars, to a greater extent, were exposed to a higher temperature and more intense sunlight for a longer time. Considerable differences in the content of LMWC could be seen both between the different cultivars and the various trials. Glucose and sucrose were generally similarly affected by cultivar and cultivation conditions, while cultivation conditions had a greater influence on the content of sorbitol and the raffinose family oligosaccharides (RFO; raffinose, stachyose, verbascose) in late‐maturing groups. It is concluded that many factors affect the content of LMWC in peas. However, as the content of RFO is comparatively small in vining peas, any nutritional significance of these sugars in the human colon is probably rather small. Copyright © 2004 Society of Chemical Industry 相似文献