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81.
Hot melt adhesives (HMAs) are formulated for the first time with different lignins as major components, and the developed HMA formulations were tested for gluing paperboard. The best formulations showed equal or even better bond strength compared to a commercial HMA reference. A maximum bond strength of 16.1 N was achieved with a formulation of oxidized cellulose acetate, organosolv lignin, and triethyl citrate, whereas the bond strength of the commercial HMA reference was 10.5 N. The performance was adjusted via the selection of lignin, the formulation, and chemical modification. Lignin modification was not necessary but provided further possibilities for adjusting the properties for different products (reversible vs irreversible adhesive seams) and also for producing plasticizer-free formulations. Modification with tall oil fatty acids enabled the formulation of fully biobased HMAs without any external plasticizer and provided a bond strength as high as high as 8.9 N. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47983. 相似文献
82.
International comparison of costs of a fatal casualty of road accidents in 1990 and 1999 总被引:3,自引:0,他引:3
The purpose of this study is to assemble information of costs per fatal casualty in traffic accidents, adopted by authorities in different countries. analyse and compare these figures as well as the methods used for estimating these values. A questionnaire was sent to 19 countries from which 11 gave information on cost per fatality and methods of valuation. The costs per fatality, usually defined as direct and indirect costs plus a value of safety per se, are compared both between countries and over time, 1990 and 1999, for each country. The average cost per fatality has increased between 1990 and 1999 (fixed prices) due to both changes in the methodology and changes of valuations. Great Britain, New Zealand, Sweden and the US conduct own willingness-to-pay (WTP) surveys, while the Netherlands and Norway make reviews of these studies. In Finland, the cost per fatality is a combination of the value of lost productivity and the cost of care for an institutionalised disabled person. In Australia, Austria, Germany and Switzerland, the cost per fatality is estimated as a value of lost productivity and an addition of a human cost based on compensation payments or insurance payments. Estimates from recently conducted WTP surveys or meta-analyses are considered in Austria, Finland and Sweden, however, not yet adopted as official values for use in road traffic planning. 相似文献
83.
Pia Ruckdeschel Martin Dulle Tobias Honold Stephan Förster Matthias Karg Markus Retsch 《Nano Research》2016,9(5):1366-1376
Herein, we fabricate hollow silica nanoparticles with exceptionally narrow size distributions that inherently possess two distinct length scales—tens of nanometers with regards to the shell thickness, and hundreds of nanometers in regards to the total diameter. We characterize these structures using dynamic and static light scattering (DLS and SLS), small angle X-ray scattering (SAXS), and transmission electron microscopy (TEM), and we demonstrate quantitative agreement among all methods. The ratio between the radius of gyration (SLS) and hydrodynamic radius (DLS) in these particles equals almost unity, corresponding to ideal capsule behavior. We are able to resolve up to 20 diffraction orders of the hollow sphere form factor in SAXS, indicating a narrow size distribution. Data from light and X-ray scattering can be combined to a master curve covering a q-range of four orders of magnitude assessing all hierarchical length scales of the form factor. The measured SLS intensity profiles noticeably change when the scattering contrast between the interior and exterior is altered, whereas the SAXS intensity profiles do not show any significant change. Tight control of the aforementioned length scales in one simple and robust colloidal building block renders these particles suitable as future calibration standards. 相似文献
84.
On-line fault detection in discrete event systems by Petri nets and integer linear programming 总被引:1,自引:0,他引:1
The paper addresses the fault detection problem for discrete event systems in a Petri Net (PN) framework. Assuming that the structure of the PN model and the initial marking are known, faults are modelled by unobservable transitions. Moreover, we assume that there may be additional unobservable transitions associated with the system legal behaviour and that the marking reached after the firing of any transition is unknown. The proposed diagnoser works on-line: it waits for the firing of an observable transition and employs an algorithm based on the definition and solution of some integer linear programming problems to decide whether the system behaviour is normal or exhibits some possible faults. The results characterize the properties that the PN modelling the system fault behaviour has to fulfill in order to reduce the on-line computational effort. 相似文献
85.
Ghiggeri GM Bruschi M Musante L Candiano G Boccardi C Citti L Rastaldi MP Mangraviti S Rosso G Larti A Rosati A Urbani A Gusmano R Bertoni E Salvadori M 《Proteomics. Clinical applications》2008,2(9):1327-1337
Little is known on both the composition and mechanism(s) of proteinuria associated with the use of mTOR inhibitors, in particular of Everolimus (E). We characterized urinary proteins utilizing an integrated proteomics approach (quantitative essays, 2‐DE, MALDI‐TOF, Western blot) in 48 renal transplant recipients who were alternatively treated with E (n = 31) or with enteric coated mycophenolic acid (EC‐MPA) (n = 17). Twelve E patients (39%) developed high (>3 g/day) or intermediate proteinuria (1–3 g) compared to four (23%) of the EC‐MPA group. Urinary proteins (p<0.001), β2 microglobulin (p<0.001) and α1microglobulin (p<0.025) were higher in E than in EC‐MPA, appeared more rapidly and were inversely correlated with the day of treatment. Proteomics showed a marked increase of all urinary components in E and EC‐MPA patients, major changes involving typical components of glomerular damage (albumin, α1‐Zn glycoprotein, α2HS glycoprotein, leucin‐richα2‐glycoprotein) and specific bio‐markers for E (clusters of α1‐antitrypsin fragments and monoclonal λ chains). Finally, inter‐α‐trypsin‐inhibitor heavy chain H4 precursor was decreased in E and EC‐MPA urine compared to normal urine. In conclusion, E induced massive and generalized proteinuria of mixed glomerular and tubular origin that was correlated with the start of treatment and reached a nephrotic range in few cases. Specific urinary markers reflect renal alterations related to the transplant or specific alterations associated with the drug. 相似文献
86.
The Coster–Kronig enhancement factor calculation for M3 shell x-ray production cross sections was found to be incorrect in both ISICSoo class (Bati? et al. (2012) [1]) and isics program (Cipolla (2013) [2]). The affected functions of ISICSoo class have been corrected. The resulting X-ray production cross sections are modified by less than 15%, while ionization cross sections are unchanged. 相似文献
87.
Anna Li Santi Filomena Napolitano Nunzia Montuori Pia Ragno 《International journal of molecular sciences》2021,22(8)
Proteolysis is a key event in several biological processes; proteolysis must be tightly controlled because its improper activation leads to dramatic consequences. Deregulation of proteolytic activity characterizes many pathological conditions, including cancer. The plasminogen activation (PA) system plays a key role in cancer; it includes the serine-protease urokinase-type plasminogen activator (uPA). uPA binds to a specific cellular receptor (uPAR), which concentrates proteolytic activity at the cell surface, thus supporting cell migration. However, a large body of evidence clearly showed uPAR involvement in the biology of cancer cell independently of the proteolytic activity of its ligand. In this review we will first describe this multifunctional molecule and then we will discuss how uPAR can sustain most of cancer hallmarks, which represent the biological capabilities acquired during the multistep cancer development. Finally, we will illustrate the main data available in the literature on uPAR as a cancer biomarker and a molecular target in anti-cancer therapy. 相似文献
88.
Identifiability is a fundamental prerequisite for model identification; it concerns uniqueness of the model parameters determined from the input-output data, under ideal conditions of noise-free observations and error-free model structure. In the late 1980s concepts of differential algebra have been introduced in control and system theory. Recently, differential algebra tools have been applied to study the identifiability of dynamic systems described by polynomial equations. These methods all exploit the characteristic set of the differential ideal generated by the polynomials defining the system. In this paper, it will be shown that the identifiability test procedures based on differential algebra may fail for systems which are started at specific initial conditions and that this problem is strictly related to the accessibility of the system from the given initial conditions. In particular, when the system is not accessible from the given initial conditions, the ideal I having as generators the polynomials defining the dynamic system may not correctly describe the manifold of the solution. In this case a new ideal that includes all differential polynomials vanishing at the solution of the dynamic system started from the initial conditions should be calculated. An identifiability test is proposed which works, under certain technical hypothesis, also for systems with specific initial conditions. 相似文献
89.
We evaluated if the theory of planned behavior explains students‘ activity in a web-based learning environment. Two of the considerations of the theory, attitude toward the behavior (behavioral beliefs and outcome evaluations) and perceived behavioral control (computer self-efficacy), were evaluated. The scope was also widened to students' approaches to learning and anxiety in computer using situations as well as their interpretations of the environment and the learning situation. Forty-two undergraduate medical and sociology students completed the questionnaire assessing attitudes, self-efficacy, anxiety and approaches to learning before and after the web-based courses. The attitude toward the behavior, efficacy beliefs, approaches to learning and anxiety in computer using situations did not predict the activity in the learning environment, but students interpreted the environment and the learning situation more negatively after the courses. Students' anxiety and approaches to learning also affect some of their expectations and experiences after the courses. 相似文献
90.
Katrin Peckert-Maier Dmytro Royzman Pia Langguth Anita Marosan Astrid Strack Atefeh Sadeghi Shermeh Alexander Steinkasserer Elisabeth Zinser Andreas B. Wild 《International journal of molecular sciences》2022,23(2)
Chronic inflammatory diseases and transplant rejection represent major challenges for modern health care. Thus, identification of immune checkpoints that contribute to resolution of inflammation is key to developing novel therapeutic agents for those conditions. In recent years, the CD83 (cluster of differentiation 83) protein has emerged as an interesting potential candidate for such a “pro-resolution” therapy. This molecule occurs in a membrane-bound and a soluble isoform (mCD83 and sCD83, respectively), both of which are involved in resolution of inflammation. Originally described as a maturation marker on dendritic cells (DCs), mCD83 is also expressed by activated B and T cells as well as regulatory T cells (Tregs) and controls turnover of MHC II molecules in the thymus, and thereby positive selection of CD4+ T cells. Additionally, it serves to confine overshooting (auto-)immune responses. Consequently, animals with a conditional deletion of CD83 in DCs or regulatory T cells suffer from impaired resolution of inflammation. Pro-resolving effects of sCD83 became evident in pre-clinical autoimmune and transplantation models, where application of sCD83 reduced disease symptoms and enhanced allograft survival, respectively. Here, we summarize recent advances regarding CD83-mediated resolution of inflammatory responses, its binding partners as well as induced signaling pathways, and emphasize its therapeutic potential for future clinical trials. 相似文献