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991.
Elnaz Shaabani Maryam Sharifiaghdam Joris Lammens Herlinde De Keersmaecker Chris Vervaet Thomas De Beer Elahe Motevaseli Mohammad Hossein Ghahremani Parvin Mansouri Stefaan De Smedt Koen Raemdonck Reza Faridi-Majidi Kevin Braeckmans Juan C. Fraire 《International journal of molecular sciences》2021,22(17)
Impaired wound healing in people with diabetes has multifactorial causes, with insufficient neovascularization being one of the most important. Hypoxia-inducible factor-1 (HIF-1) plays a central role in the hypoxia-induced response by activating angiogenesis factors. As its activity is under precise regulatory control of prolyl-hydroxylase domain 2 (PHD-2), downregulation of PHD-2 by small interfering RNA (siRNA) could stabilize HIF-1α and, therefore, upregulate the expression of pro-angiogenic factors as well. Intracellular delivery of siRNA can be achieved with nanocarriers that must fulfill several requirements, including high stability, low toxicity, and high transfection efficiency. Here, we designed and compared the performance of layer-by-layer self-assembled siRNA-loaded gold nanoparticles with two different outer layers—Chitosan (AuNP@CS) and Poly L-arginine (AuNP@PLA). Although both formulations have exactly the same core, we find that a PLA outer layer improves the endosomal escape of siRNA, and therefore, transfection efficiency, after endocytic uptake in NIH-3T3 cells. Furthermore, we found that endosomal escape of AuNP@PLA could be improved further when cells were additionally treated with desloratadine, thus outperforming commercial reagents such as Lipofectamine® and jetPRIME®. AuNP@PLA in combination with desloratadine was proven to induce PHD-2 silencing in fibroblasts, allowing upregulation of pro-angiogenic pathways. This finding in an in vitro context constitutes a first step towards improving diabetic wound healing with siRNA therapy. 相似文献
992.
In this study, the effect of the ARB process on the passive behavior of ultra-fine-grained 1050 aluminum alloy in a borate buffer solution(p H 6.0) has been investigated. The result of the microhardness tests revealed that the microhardness values increase with an increasing number of ARB cycles. The potentiodynamic polarization plots revealed that the higher number of cycles for the specimens proceeds with the ARB process rather than annealing yield to lower corrosion and passive current densities and more noble corrosion potential values. Moreover, electrochemical impedance spectroscopy measurements showed that increasing the number of ARB cycles offers better conditions for forming the passive films. 相似文献
993.
Decision-making in detecting and diagnosing faults of multivariate statistical quality control systems 总被引:1,自引:1,他引:0
Seyed Taghi Akhavan Niaki Mohammad Saber Fallah Nezhad 《The International Journal of Advanced Manufacturing Technology》2009,42(7-8):713-724
A new methodology is proposed in this paper to both monitor an overall mean shift and classify the states of a multivariate quality control system. Based on the Bayesian rule (Montgomery, Introduction to statistical quality control, 5th edn. Wiley, New York, USA, 2005), the belief that each quality characteristic is in an out-of-control state is first updated in an iterative approach and the proof of its convergence is given. Next, the decision-making process of the detection and classification the process mean shift is modeled. Numerical examples by simulation are provided in order to understand the proposed methodology and to evaluate its performance. Moreover, the in-control and out-of-control average run length (Montgomery, Introduction to statistical quality control, 5th edn. Wiley, New York, USA, 2005) of the proposed method are compared with the ones from the well-known Multivariate Cumulative Sum (MCUSUM), Multivariate Exponentially Weighted Moving Average (MEWMA) and Hotelling T 2 methods in different scenarios of mean shifts. The results of the simulation study show that the proposed methodology performs better than other methods for all shifts of the process mean. Additionally, the estimated probabilities of making correct classifications by the proposed approach are encouraging. 相似文献
994.
Md. Shaheed Reza Mohammad A. J. Bapary Chowdhury T. Ahasan Md. Nazrul Islam & Md. Kamal 《International Journal of Food Science & Technology》2009,44(8):1485-1494
Organoleptic, biochemical and bacteriological aspects of five tropical marine fish such as silver jewfish, Bombay duck, big-eye tuna, Chinese pomfret and ribbon fish stored in ice were studied. Organoleptically all fish were found acceptable for 10–13 days before becoming inedible. Proximate analysis showed that moisture content increased slightly; protein and lipid content decreased gradually and ash had little or no significant change. pH, TVB-N, peroxide and aerobic plate count values increased with increasing storage period but the values were within acceptable range up to 10 days of storage. Changes in myofibrillar ATPase activity and solubility of these fishes showed that Ca2+ ATPase in the presence of both 0.1 m and 0.5 m KCl decreased gradually whereas no marked changes were observed in the Mg+2 ATPase activities in the presence/absence of Ca+2 . Myofibrillar protein solubility of all fish samples also decreased considerably during ice storage. The decrement in Ca2+ ATPase activity and solubility indicates denaturation of myofibrillar protein of fish samples during ice storage. 相似文献
995.
Ali Jahanban Sfahlan Ahmad Mahmoodzadeh Abdollah Hasanzadeh Reza Heidari Rashid Jamei 《Food chemistry》2009
To compare the antioxidant and antiradical activity of Amygdalus communis L. hulls and shells phenolic extracts in different genotypes, 18 A. communis L. genotypes were selected from those in Qooshchi, Qalgachi, Qovarchin Qale, Najaf Abad, Jamal Abad, Kahriz, Sfahlan of West and East Azerbayjan provinces of Iran in 2007. The fruits of these almonds were collected, their hulls and shells dried, ground and then methanolic extracts prepared from these hulls and shells. Total phenolic content was determined using the Folin–Ciocalteu (F–C) method. The extracts’ reducing power and scavenging capacity for radical nitrite, hydrogen peroxide and superoxide were evaluated. Significant differences were found in phenolic content of hulls and shells among various genotypes, radical scavenging capacity percentage varied significantly among genotypes and their hulls and shells. S3-7 genotype with the highest phenolic content and antioxidant activity in its hulls represents a valuable genotype for procuring antioxidant phenolic compounds. 相似文献
996.
We consider the many-help-one problem, also called m-helper problem, for the special case of m = 1 where one source provides partial side information to the fusion center (FC) to help reconstruction of the other correlated source. Both correlated sources communicate information about their observations to the FC through an orthogonal multiple access channel (MAC) without cooperating with each other. First, we characterize the optimal tradeoff between the transmission cost, that is, power, and the distortion D. Then, we consider a joint optimization of source coding and power scheduling from an information theory perspective, where the power scheduling is verified using Shannon capacity formula and the source-coding problem is analyzed using rate-distortion theory. We show that the joint optimization in the Gaussian one-helper problem can be solved analytically. We provide closed-form expressions for the optimal distortion and the optimal power scheduling in terms of the cost weights. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
997.
Mohammad Reza Nabid Maryam Golbabaee Abdolmajid Bayandori Moghaddam Ali Reza Mahdavian Mostafa Mohammadpour Amini 《Polymer Composites》2009,30(6):841-846
Peroxidase-catalyzed template-guided polymerization of aniline in the presence of γ- alumina nanosheet (NS) particles have been carried out in aqueous media and γ-Al2O3/PANI nanocomposite was obtained. The polymerization of aniline occurred in aqueous solution in the presence of SPS (sulfonated polystyrene) as a template and SDS (sodium dodecyl sulfate) as a surfactant. Both obtained nanocomposites were comparable by SEM images. It was demonstrated that the γ-Al2O3 NS/PANI-SPS nanocomposite has higher conductivity and the γ-Al2O3 NS/PANI-SDS nanocomposite has higher void areas. The higher conductivity of γ-Al2O3 NS/PANI-SPS nanocomposite is attributed to the higher coated areas of γ-Al2O3 NS during polymerization in comparison with γ-Al2O3 NS/PANI-SDS which are not coated efficiently as the former. The FT-IR studies showed that the γ-Al2O3 NS/PANI nanocomposite was formed by interaction of the polyaniline (PANI) and γ-Al2O3 NS. FTIR also showed that the amount of PANI in γ-Al2O3 NS/PANI-SPS is more than in γ-Al2O3 NS/PANI-SDS. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers 相似文献
998.
Simple and efficient directly suspended droplet micro extraction (DSDME) in conjunction with gas chromatography-electron capture detector (GC-ECD) has been developed for extraction and determination of Halomethane and Trihalomethane from water samples. In this technique a micro drop of n-hexane is delivered to the surface of an aqueous sample while being agitated by a stirring bar in the bulk of solution. Factors relevant to the extraction efficiency were studied and optimized. The optimized extraction conditions were extraction solvent: n- hexane; NaCl concentration: 1 M; solvent extraction volume: 50 μL; stirring rate: 720 rpm and the extraction time: 5 min. The detection limits of the method were in the range of 0.059–0.137 µg L?1, relative standard deviation (n = 3) range were 0.019–0.048%. A good linearity (r2 ≥ 0.997) and a relatively broad dynamic linear range (10–200 µg L?1) were obtained and recoveries of method were in the range of 97.69–99.51%. Finally, the proposed method was successfully utilized for pre concentration and determination of halo methane in different real samples. Successfully DSDME technique combined with capillary GC-ECD for the analysis of THMs and HMs in the water investigated samples. 相似文献
999.
Ali Asghar Atai Mohammad Hassan Naei Reza Eghtefari 《Journal of Mechanical Science and Technology》2010,24(11):2247-2252
Snap-through is an instability phenomenon that occurs in arch and dome-shaped structures, wherein the structure has to move
from a stable equilibrium state through an unstable path into another stable equilibrated configuration in a jumping action.
In this study, a linear elastic isotropic low arch is considered as a structure with power-law variable thickness. The phenomenon
is investigated by considering the equation of the deflection for the variable thickness arch, solving it with an elegant
analytical technique, and finding the snap-through critical load from an extreme condition. The effect of power-law exponent
and geometry of the arch centerline on critical load is investigated and the constant thickness case and a very rare case
of power-law thickness variation found in literature are considered for verification. 相似文献
1000.
Shahrokh Hosseini-Hashemi Mohammad Reza Ilkhani Mohammad Fadaee 《Acta Mechanica》2012,223(5):1101-1118
Free vibration of Levy-type thick functionally graded (FG) circular cylindrical shell panels is investigated to identify the
validity range of two common shell theories namely Donnell and Sanders theories. FG material properties change through the
thickness direction according to a power law distribution. The state space approach is applied to solve the problem. The present
results are compared with those of the literature and a 3D finite element model for isotropic and FG materials. The effects
of various geometry and material parameters on the validity range of these theories are studied for different boundary conditions.
The results show that unlike Sanders theory, Donnell one cannot accurately capture natural boundary conditions such as force
and moment resultants. 相似文献