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71.
Anna Aiello Mattia Emanuela Ligotti Maider Garnica Giulia Accardi Anna Calabr Fanny Pojero Hugo Arasanz Ana Bocanegra Ester Blanco Luisa Chocarro Miriam Echaide Leticia Fernandez-Rubio Pablo Ramos Sergio Pieiro-Hermida Grazyna Kochan Nahid Zareian Farzin Farzaneh David Escors Calogero Caruso Giuseppina Candore 《International journal of molecular sciences》2022,23(17)
Vaccination, being able to prevent millions of cases of infectious diseases around the world every year, is the most effective medical intervention ever introduced. However, immunosenescence makes vaccines less effective in providing protection to older people. Although most studies explain that this is mainly due to the immunosenescence of T and B cells, the immunosenescence of innate immunity can also be a significant contributing factor. Alterations in function, number, subset, and distribution of blood neutrophils, monocytes, and natural killer and dendritic cells are detected in aging, thus potentially reducing the efficacy of vaccines in older individuals. In this paper, we focus on the immunosenescence of the innate blood immune cells. We discuss possible strategies to counteract the immunosenescence of innate immunity in order to improve the response to vaccination. In particular, we focus on advances in understanding the role and the development of new adjuvants, such as TLR agonists, considered a promising strategy to increase vaccination efficiency in older individuals. 相似文献
72.
Ying Lin Fanghui Yin Yuhao Liu Liming Wang Yunfeng Zhao Masoud Farzaneh 《应用聚合物科学杂志》2019,136(24):47652
Liquid silicone rubber (LSR) products outdoors are often subjected to high intensity of ultraviolet (UV)-A radiation. However, the influence of UV-A radiation on LSR is rarely studied. To study the influence of UV-A radiation on LSR, the surface of LSR with UV-A aging time was characterized by tests at different detection depths [X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR)]. The operation properties (thermal stability and mechanical and electrical properties) for outdoor insulators were also analyzed. It was found that the porous surface and the loose layer of LSR increased, but the growth rate of them decreased as UV-A aging time increased. SiO2 fillers were lost in the surface. C H bonds in CH3 and CH3 in Si CH3 increased with aging time. The increased crosslinking density increased the thermal stability, hardness, dielectric loss tangent, relative dielectric constant, and volume resistivity and decreased elongation-at-break. The mechanical strength initially increased and then decreased. Based on the proposed aging mechanism, the UV-A resistance of LSR can be improved by reducing the amount of hydrogen-containing silicone oil and by increasing the molecular weight of raw rubber. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47652. 相似文献
73.
Samaneh Sanjari Hanieh Mohammad Gholizadeh Farzaneh Vahabzadeh 《Chemical Engineering Communications》2019,206(3):289-300
Cyclodextrin glucanotransferase (CGTase) production was studied using loofa-immobilized Bacillus sp. DSM 2523 and starch substrate. The bacterial cells from 2- and 4-day old cultures were used in the flask studies. Loofa and chitosan were added for cell immobilization and cell flocculation, respectively, and different treatments were considered according to the timing of their addition. The cell responses were evaluated for their degree of cell immobilization and level of CGTase activity. With the use of the selected treatment, testing was carried out in an airlift reactor with a net draft tube having specific geometric properties. The cell capacity for reusability also was examined. The production of CGTase was higher in the second cycle in the reactor operated at 0.25 vvm where the enzyme activity reaching 0.20?U/ml within 2?h. In the flask experiments, CGTase activity reached 0.23?U/ml after 19?h in the second cycle. 相似文献
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77.
In this study the structural and electronic properties of III-nitride monolayers XN(X=B, Al, Ga and In) under different percentages of homogeneous and shear strain are investigated using the full potential linearized augmented plane wave within the density functional theory. Geometry optimizations indicate that GaN and InN monolayers get buckled under compressive strain.Our calculations show that the free-strains of these four monolayers have an indirect band gap. By applying compressive biaxial strain, a transition from indirect to direct band gap occurs for GaN and InN, while the character of band gap for BN and AlN is not changed. Under tensile strain, only BN monolayer behaves as direct band gap semiconductor. In addition, when the shear strain is applied, only InN undergoes an indirect to direct band gap transition. Furthermore, the variations of band gap versus strain for III-nitride monolayers have been calculated. When a homogeneous uniform strain, in the range of [.10%, +10%], is applied to the monolayers, the band gap can be tuned for from 3.92 eV to 4.58 eV for BN, from 1.67 eV to 3.46 eV for AlN, from0.24 eV to 2.79 eV for GaN and from 0.60 eV to 0.90 eV for InN. 相似文献
78.
Influences of nonassociated flow rules on three-dimensional seismic stability of loaded slopes 总被引:1,自引:1,他引:0
The influences of soil dilatancy angle on three-dimensional (3D) seismic stability of locally-loaded slopes in nonassociated flow rule materials were investigated using a new rotational collapse mechanism and quasi-static coefficient concept. Extended Bishop method and Boussinesq theorem were employed to establish the stress distribution along the rupture surfaces that are required to obtain the rate of internal energy dissipation for the nonassociated flow rule materials in rotational collapse mechanisms. Good agreement was observed by comparing the current results with those obtained using the translational or rotational mechanisms and numerical finite difference method. The results indicate that the seismic stability of slopes reduces by decreasing the dilatancy angle for nonassociated flow rule materials. The amount of the mentioned decrease is more significant in the case of mild slopes in frictional soils. A nearly infinite slope under local loading, whether its critical failure surface is 2D or 3D, not only depends on the magnitude of the external load, but also depends on the dilatancy angle of soil and the coefficient of seismic load. 相似文献
79.
Yadollah Farzaneh Alireza Akbarzadeh Ali Akbar Akbari 《Intelligent Service Robotics》2012,5(3):169-177
In this paper, we suggest a new supervised learning method called Fourier based automated learning central pattern generators (FAL-CPG), for learning rhythmic signals. The rhythmic signal is analyzed with Fourier analysis and fitted with a finite Fourier series. CPG parameters are selected by direct comparison with the Fourier series. It is shown that the desired rhythmic signal is learned and reproduced with high accuracy. The resulting CPG network offers several advantages such as, modulation and robustness against perturbation. The proposed learning method is simple, straightforward and efficient. Furthermore, it is suitable for on-line applications. The effectiveness of the proposed method is shown by comparison with four other supervised learning methods as well as an industrial robotic trajectory following application. 相似文献
80.
Farzaneh Aminpour Payam Kabiri Mohammad Ali Boroumand Abbas Ali Keshtkar Seyed Shamsoddin Hejazi 《Scientometrics》2010,85(1):53-63
Patenting and licensing is not only a significant method of university knowledge transfer, but also an important indicator
for measuring academic R&D strength and knowledge utilization. The methodologies of quantitative and qualitative analysis,
including a special patent h-index indicator to assess patenting quality, were used to examine university patenting worldwide. Analysis of university
patenting from 1998 to 2008 showed a significant overall global increase in which Chinese academia stands out: most of the
top 20 universities in patenting in 2008 were in China. However, a low rate of utilization of Chinese academic patents may
have roots in: (1) university research evaluation system encourages the patent production more, rather than the utilization;
(2) problems in the formal mechanisms for university technology transfer and licensing, (3) industry’s limited expectation
and receptive capabilities and/or (4) a mismatch between the interests of the two institutional spheres. The next action to
be taken by government, university and industry in China will be to explore strategies for improving academic patent quality
and industry take-up. 相似文献