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991.
针对气候变化和城市化对富饶的三角洲地区带来的洪涝风险、生态、社会—文化价值流失等威胁,提出将三角洲城市化进程视为一系列具有独立动态特征和速率变化的复杂社会—生态系统(子系统),急需为保障该类型区域的可持续发展提供空间战略,以协助修复系统漏洞并增强应对自然和人工威胁的能力,以珠江三角洲为例,针对城市化进程中三角洲区域的适应性城市转型,提出基于景观的区域设计方法。通过对自然和城市景观要素转型性循环的各类动态变化进行评估,得到生态动力型区域设计战略,为城市化进程中的自然和社会—文化发展提供更多机遇。提出保障水安全和全纳性社会—生态设计的适应性转型视角。 相似文献
992.
辅助驾驶系统开发面临的挑战 汽车辅助驾驶(DA)系统工程师通常使用PC模型来创建复杂的处理算法,以便实现高度可靠的自适应巡航控制、车道偏离警告及行人检测等功能.开发人员高度重视PC算法模型,因为这种模型使他们能够尝试使用并快速评估不同的处理算法.不过,说到底,还是需要一款设计合理的电子硬件解决方案,来实现经济有效的大规模生产与部署. 相似文献
993.
Daniele Menon Stefano Andriani Giancarlo Calvagno 《IEEE transactions on image processing》2007,16(1):132-141
Most digital cameras use a color filter array to capture the colors of the scene. Downsampled versions of the red, green, and blue components are acquired, and an interpolation of the three colors is necessary to reconstruct a full representation of the image. This color interpolation is known as demosaicing. The most effective demosaicing techniques proposed in the literature are based on directional filtering and a posteriori decision. In this paper, we present a novel approach to this reconstruction method. A refining step is included to further improve the resulting reconstructed image. The proposed approach requires a limited computational cost and gives good performance even when compared to more demanding techniques. 相似文献
994.
The optical properties of ZnO nanoparticles(NPs) fabricated by three different methods were studied by the UV-excited continuous wave photoluminescence in order to estimate their down-shifting(DS) efficiency. Such a luminescent layer modifies the incident solar radiation via emitting wavelengths better matching the spectral response of the underlying photosensitive device(photodiode),thereby increasing its efficiency.Some of the studied ZnO NPs were subsequently deposited on the front side of commercial silicon photodiodes and the external quantum efficiency(EQE) characteristics of the final devices were measured.Through comparison of the photodiode’s EQE characteristics before and after the deposition of the ZnO NPs layer,it was concluded that for the photodiode with a low UV sensitivity(about 8%),the ZnO luminescent layer produces a down-shifting effect and the EQE in the UV and blue range improves by 16.6%,while for the photodiodes with a higher initial UV sensitivity(about 50%),the EQE in this range decreases with the ZnO layer thickness,due to the effects competing with DS,like the diminution of the ZnO layer transmittance and an increasing diffusion. 相似文献
995.
Asad Jamal Tian Yuan Stefano Galvan Antonella Castellano Marco Riva Riccardo Secoli Andrea Falini Lorenzo Bello Ferdinando Rodriguez y Baena Daniele Dini 《International journal of molecular sciences》2022,23(6)
Targeted drug delivery in the brain is instrumental in the treatment of lethal brain diseases, such as glioblastoma multiforme, the most aggressive primary central nervous system tumour in adults. Infusion-based drug delivery techniques, which directly administer to the tissue for local treatment, as in convection-enhanced delivery (CED), provide an important opportunity; however, poor understanding of the pressure-driven drug transport mechanisms in the brain has hindered its ultimate success in clinical applications. In this review, we focus on the biomechanical and biochemical aspects of infusion-based targeted drug delivery in the brain and look into the underlying molecular level mechanisms. We discuss recent advances and challenges in the complementary field of medical robotics and its use in targeted drug delivery in the brain. A critical overview of current research in these areas and their clinical implications is provided. This review delivers new ideas and perspectives for further studies of targeted drug delivery in the brain. 相似文献
996.
Federica Sola Mariele Montanari Mara Fiorani Chiara Barattini Caterina Ciacci Sabrina Burattini Daniele Lopez Alfredo Ventola Loris Zamai Claudio Ortolani Stefano Papa Barbara Canonico 《International journal of molecular sciences》2022,23(6)
Fluorescent silica nanoparticles (SiNPs) appear to be a promising imaging platform, showing a specific subcellular localization. In the present study, we first investigated their preferential mitochondrial targeting in myeloid cells, by flow cytometry, confocal microscopy and TEM on both cells and isolated mitochondria, to acquire knowledge in imaging combined with therapeutic applications. Then, we conjugated SiNPs to one of the most used anticancer drugs, doxorubicin (DOX). As an anticancer agent, DOX has high efficacy but also an elevated systemic toxicity, causing multiple side effects. Nanostructures are usually employed to increase the drug circulation time and accumulation in target tissues, reducing undesired cytotoxicity. We tested these functionalized SiNPs (DOX-NPs) on breast cancer cell line MCF-7. We evaluated DOX-NP cytotoxicity, the effect on the cell cycle and on the expression of CD44 antigen, a molecule involved in adhesion and in tumor invasion, comparing DOX-NP to free DOX and stand-alone SiNPs. We found a specific ability to release a minor amount of CD44+ extracellular vesicles (EVs), from both CD81 negative and CD81 positive pools. Modulating the levels of CD44 at the cell surface in cancer cells is thus of great importance for disrupting the signaling pathways that favor tumor progression. 相似文献
997.
Alessia Remigante Sara Spinelli Nancy Basile Daniele Caruso Giuseppe Falliti Silvia Dossena Angela Marino Rossana Morabito 《International journal of molecular sciences》2022,23(14)
Aging is a multi-factorial process developing through a complex net of interactions between biological and cellular mechanisms and it involves oxidative stress (OS) as well as protein glycation. The aim of the present work was to verify the protective role of Quercetin (Q), a polyphenolic flavonoid compound, in a d-Galactose (d-Gal)-induced model of aging in human erythrocytes. The anion-exchange capability through the Band 3 protein (B3p) measured by the rate constant of the SO42− uptake, thiobarbituric acid reactive substances (TBARS) levels—a marker of lipid peroxidation—total sulfhydryl (-SH) groups, glycated hemoglobin (A1c), and a reduced glutathione/oxidized glutathione (GSH-GSSG) ratio were determined following the exposure of erythrocytes to 100 mM d-Gal for 24 h, with or without pre-incubation with 10 µM Q. The results confirmed that d-Gal activated OS pathways in human erythrocytes, affecting both membrane lipids and proteins, as denoted by increased TBARS levels and decreased total sulfhydryl groups, respectively. In addition, d-Gal led to an acceleration of the rate constant of the SO42− uptake through the B3p. Both the alteration of the B3p function and oxidative damage have been improved by pre-treatment with Q, which preferentially ameliorated lipid peroxidation rather than protein oxidation. Moreover, Q prevented glycated A1c formation, while no protective effect on the endogenous antioxidant system (GSH-GSSG) was observed. These findings suggest that the B3p could be a novel potential target of antioxidant treatments to counteract aging-related disturbances. Further studies are needed to confirm the possible role of Q in pharmacological strategies against aging. 相似文献
998.
Daniele Capitanio Manuela Moriggi Pietro Barbacini Enrica Torretta Isabella Moroni Flavia Blasevich Lucia Morandi Marina Mora Cecilia Gelfi 《International journal of molecular sciences》2022,23(5)
BMD is characterized by a marked heterogeneity of gene mutations resulting in many abnormal dystrophin proteins with different expression and residual functions. The smaller dystrophin molecules lacking a portion around exon 48 of the rod domain, named the D8 region, are related to milder phenotypes. The study aimed to determine which proteins might contribute to preserving muscle function in these patients. Patients were subdivided, based on the absence or presence of deletions in the D8 region, into two groups, BMD1 and BMD2. Muscle extracts were analyzed by 2-D DIGE, label-free LC-ESI-MS/MS, and Ingenuity pathway analysis (IPA). Increased levels of proteins typical of fast fibers and of proteins involved in the sarcomere reorganization characterize BMD2. IPA of proteomics datasets indicated in BMD2 prevalence of glycolysis and gluconeogenesis and a correct flux through the TCA cycle enabling them to maintain both metabolism and epithelial adherens junction. A 2-D DIGE analysis revealed an increase of acetylated proteoforms of moonlighting proteins aldolase, enolase, and glyceraldehyde-3-phosphate dehydrogenase that can target the nucleus promoting stem cell recruitment and muscle regeneration. In BMD2, immunoblotting indicated higher levels of myogenin and lower levels of PAX7 and SIRT1/2 associated with a set of proteins identified by proteomics as involved in muscle homeostasis maintenance. 相似文献
999.
Gabriella Serio Federica Pezzuto Francesco Fortarezza Andrea Marzullo Maria Celeste Delfino Antonio dAmati Daniele Egidio Romano Sonia Maniglio Concetta Caporusso Teresa Lettini Domenica Cavone Luigi Vimercati 《International journal of molecular sciences》2022,23(5)
There is evidence that asbestos could play a role in the carcinogenesis of digestive cancers. The presence of asbestos fibres in histological samples from gastric, biliary, colon cancers has been reported, but the mechanism is still controversial. It has been hypothesised that asbestos reaches these sites, especially through contaminated water; however, some experimental studies have shown that the inhaled fibres are mobile, so they can migrate to many organs, directly or via blood and lymph flow. We report four unusual cases of colorectal cancers in patients with a long history of asbestos exposure who also developed synchronous or metachronous mesothelioma. We evaluated the roles of BRCA associated protein-1 (BAP1) and cyclin-dependent kinase inhibitor 2A (CDKN2A) in colon cancer and mesothelioma to support the hypothesis that BAP-1 and CDKN2A are tumour suppressor genes involved in disease progression, recurrence, or death in both digestive cancers and mesothelioma. Potentially, these markers may be used as predictors of worse prognosis, but we also stress the importance of clinical surveillance of exposed patients because asbestos could induce cancer in any organ. 相似文献
1000.
Débora Villaño Daniele Lettieri-Barbato Fiorella Guadagni Marc Schmid Mauro Serafini 《Food chemistry》2012
We evaluated the ability of a ready-to-drink oolong tea (OOL) to modulate plasma antioxidant status in healthy subjects, compared to a placebo drink (PLA) without oolong extract but with ascorbic acid. In vitro, ascorbic acid was the only contributor to ferric reducing antioxidant power (FRAP) and total radical-trapping antioxidant parameter (TRAP) assay of PLA. Ascorbic acid contributed 16.5% and 9.7% of the antioxidant capacity of OOL. In vivo, ingestion of 500 mL of OOL significantly increased plasma TRAP at 30 min and 1 h, compared to 500 mL of PLA, which was ineffective. Plasma FRAP significantly increased at 1, 2 and 4 h for OOL and at 2 h for PLA. Both PLA and OOL significantly increased urinary FRAP over 0–5 h. Urinary FRAP levels went back to baseline at 5 h for PLA tea and remained higher for OOL tea in the interval time 5–12 h (p < 0.01). OOL represents a dietary source of antioxidants able to modulate antioxidant status in humans. 相似文献