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151.
Information represents one of the most important factors in the success of any enterprise today. Moreover, confidential information is becoming increasingly integrated into complex info-innovation solutions and is accordingly exposed to novel means of manipulation and theft. The legal requirements concerning information security (IS) policies in organizations are mainly based on reactive approaches that follow the standards applied in this area and are regularly updated every few years. However, a complementary approach that takes into account a fast-changing information/innovation security threats landscape and that is of proactive nature is required. Such an approach is presented in this article by linking the information security field with the field of innovation management. 相似文献
152.
David Bommes Bruno Lévy Nico Pietroni Enrico Puppo Claudio Silva Marco Tarini Denis Zorin 《Computer Graphics Forum》2013,32(6):51-76
Triangle meshes have been nearly ubiquitous in computer graphics, and a large body of data structures and geometry processing algorithms based on them has been developed in the literature. At the same time, quadrilateral meshes, especially semi‐regular ones, have advantages for many applications, and significant progress was made in quadrilateral mesh generation and processing during the last several years. In this survey we discuss the advantages and problems of techniques operating on quadrilateral meshes, including surface analysis and mesh quality, simplification, adaptive refinement, alignment with features, parametrisation and remeshing. 相似文献
153.
This paper presents a dynamic integration algorithm to triangulate a surface from multiple range views. This integration technique is based on the reparameterization of the canonic subsets of the Venn diagram of the set of range views. We compute a model based onN views from a model based onN–1 views by processing only the surface segments visible in theN
th view. An experimental result shows that the proposed integration algorithm can process complex multipart objects containing holes. 相似文献
154.
Peruzzo D Bertoldo A Zanderigo F Cobelli C 《Computer methods and programs in biomedicine》2011,104(3):e148-e157
Dynamic susceptibility contrast-magnetic resonance imaging (DSC-MRI) data analysis requires the knowledge of the arterial input function (AIF) to quantify the cerebral blood flow (CBF), volume (CBV) and the mean transit time (MTT). AIF can be obtained either manually or using automatic algorithms. We present a method to derive the AIF on the middle cerebral artery (MCA). The algorithm draws a region of interest (ROI) where the MCA is located. Then, it uses a recursive cluster analysis on the ROI to select the arterial voxels. The algorithm had been compared on simulated data to literature state of art automatic algorithms and on clinical data to the manual procedure. On in silico data, our method allows to reconstruct the true AIF and it is less affected by partial volume effect bias than the other methods. In clinical data, automatic AIF provides CBF and MTT maps with a greater contrast level compared to manual AIF ones. Therefore, AIF obtained with the proposed method improves the estimate reliability and provides a quantitatively reliable physiological picture. 相似文献
155.
Gerstorf Denis; Ram Nilam; Mayraz Guy; Hidajat Mira; Lindenberger Ulman; Wagner Gert G.; Schupp Jürgen 《Canadian Metallurgical Quarterly》2010,25(2):477
Throughout adulthood and old age, levels of well-being appear to remain relatively stable. However, evidence is emerging that late in life well-being declines considerably. Using long-term longitudinal data of deceased participants in national samples from Germany, the United Kingdom, and the United States, we examined how long this period lasts. In all 3 nations and across the adult age range, well-being was relatively stable over age but declined rapidly with impending death. Articulating notions of terminal decline associated with impending death, we identified prototypical transition points in each study between 3 and 5 years prior to death, after which normative rates of decline steepened by a factor of 3 or more. The findings suggest that mortality-related mechanisms drive late-life changes in well-being and highlight the need for further refinement of psychological concepts about how and when late-life declines in psychosocial functioning prototypically begin. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
156.
157.
Fitsum Guebre-Egziabher Firas Easy Laurent Juillard Pierre-Jean Valette Denis Fouque 《Hemodialysis international. International Symposium on Home Hemodialysis》2004,8(3):214-218
Renal hyperparathyroidism is one of the main and serious complications that occur in chronic kidney disease and particularly during long‐term maintenance dialysis. Several recent trials indicate that a high calcium phosphorus product is correlated with high cardiovascular morbidity and mortality and poor outcome. Thus, it is important to improve the control of hyperparathyroidism in chronic renal failure patients. Several methods have been reported for treating severe hyperparathyroidism resistant to medical therapy. Total parathyroidectomy and transplantation or excision of tumor is considered as the treatment of choice. More recently, interventional methods with percutaneous ethanol or calcitriol injection have been developed. These latter techniques have been reported as an alternative to surgical treatment for patients with high perioperative risk. We report the occurrence of laryngeal recurrent nerve palsy, vocal fold paralysis, and hemiplegia after a successful injection of ethanol in a left parathyroid adenoma in a maintenance hemodialysis patient and discuss the restrictions of the procedure and alternative treatments in view of the available studies. 相似文献
158.
Konstantin Zimenko Andrey Polyakov Denis Efimov Wilfrid Perruquetti 《International journal of control》2020,93(6):1353-1361
ABSTRACTControl laws are designed for stabilisation of a chain of integrators of arbitrary degree in finite and fixed time. Presented control laws are obtained with use of Lyapunov function method and homogeneity concept. The present analysis is based on use of explicitly defined Lyapunov function that is the hallmark with respect to similar works. This analysis allows to get simple procedure of parameters tuning and obtain new estimates for settling-time function. The theoretical results are supported by numerical examples. 相似文献
159.
Monika Kova
evi Dora Markulin Matea Zelenika Marko Marjanovi Marija Lovri Denis Polan
ec Marina Ivan
i Jasna Mrv
i Kreimir Mol
anov Valentina Milainovi Sun
ica Roca Ivan Kodrin Lidija Barii 《International journal of molecular sciences》2022,23(20)
Considering the enormous importance of protein turns as participants in various biological events, such as protein–protein interactions, great efforts have been made to develop their conformationally and proteolytically stable mimetics. Ferrocene-1,1′-diamine was previously shown to nucleate the stable turn structures in peptides prepared by conjugation with Ala (III) and Ala–Pro (VI). Here, we prepared the homochiral conjugates of ferrocene-1,1′-diamine with l-/d-Phe (32/35), l-/d-Val (33/36), and l-/d-Leu (34/37) to investigate (1) whether the organometallic template induces the turn structure upon conjugation with amino acids, and (2) whether the bulky or branched side chains of Phe, Val, and Leu affect hydrogen bonding. Detailed spectroscopic (IR, NMR, CD), X-ray, and DFT studies revealed the presence of two simultaneous 10-membered interstrand hydrogen bonds, i.e., two simultaneous β-turns in goal compounds. A preliminary biological evaluation of d-Leu conjugate 37 showed its modest potential to induce cell cycle arrest in the G0/G1 phase in the HeLa cell line but these results need further investigation. 相似文献
160.
Mohammed Mahmoud Yuqiong Liu Holly Hartmann Steven Stewart Thorsten Wagener Darius Semmens Robert Stewart Hoshin Gupta Damian Dominguez Francina Dominguez David Hulse Rebecca Letcher Brenda Rashleigh Court Smith Roger Street Jenifer Ticehurst Mark Twery Hedwig van Delden Ruth Waldick Denis White Larry Winter 《Environmental Modelling & Software》2009,24(7):798-808
Scenarios are possible future states of the world that represent alternative plausible conditions under different assumptions. Often, scenarios are developed in a context relevant to stakeholders involved in their applications since the evaluation of scenario outcomes and implications can enhance decision-making activities. This paper reviews the state-of-the-art of scenario development and proposes a formal approach to scenario development in environmental decision-making. The discussion of current issues in scenario studies includes advantages and obstacles in utilizing a formal scenario development framework, and the different forms of uncertainty inherent in scenario development, as well as how they should be treated. An appendix for common scenario terminology has been attached for clarity. Major recommendations for future research in this area include proper consideration of uncertainty in scenario studies in particular in relation to stakeholder relevant information, construction of scenarios that are more diverse in nature, and sharing of information and resources among the scenario development research community. 相似文献