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1.

Wireless nanonetworks are not a simple extension of traditional communication networks at the nano-scale. Owing to being a completely new communication paradigm, existing research in this field is still at an embryonic stage. Furthermore, most of the existing studies focus on performance enhancement of nanonetworks via designing new channel models and routing protocols. However, the impacts of different types of nano-antennas on the network-level performances of the wireless nanonetworks remain still unexplored in the literature. Therefore, in this paper, we explore the impacts of different well-known types of antennas such as patch, dipole, and loop nano-antennas on the network-level performances of wireless nanonetworks. We also investigate the performances of nanonetworks for different types of traditional materials (e.g., copper) and for nanomaterials (e.g., carbon nanotubes and graphene). We perform rigorous simulation using our customized ns-2 simulation to evaluate the network-level performances of nanonetworks exploiting different types of nano-antennas using different materials. Our evaluation reveals a number of novel findings pertinent to finding an efficient nano-antenna from its several alternatives for enhancing network-level performances of nanonetworks. Our evaluation demonstrates that a dipole nano-antenna using copper material exhibits around 51% better throughput and about 33% better end-to-end delay compared to other alternatives for large-size nanonetworks. Furthermore, our results are expected to exhibit high impacts on the future design of wireless nanonetworks through facilitating the process of finding the suitable type of nano-antenna and suitable material for the nano-antennas.

  相似文献   
2.
Designing a mood board is a creative tool designers often employ at the start of a new (interior) design project. The colors of a mood board represent important information about the envisioned interior designs. In this article, we focus on digital mood boards and we propose a novel method to determine the mood boards' key colors from a design perspective using dE-means color clustering. This proposed algorithm includes a fixed initialization to overcome the non-deterministic nature of traditional k-means, and a merging step to ensure all colors in the calculated palette are at least a dE-threshold apart. Quantitative and qualitative results demonstrate that the proposed algorithm outperforms existing methods in determining the key colors from a design perspective. Additionally, we introduce a novel method to visualize the calculated color palettes that takes into account the contribution of individual pixels to the construction of the calculated color palettes. Finally, we demonstrate how the proposed algorithm can be used to characterize color palettes for various design styles like modern, industrial and art deco.  相似文献   
3.
In this paper, the synthesis of continuous mullite (3Al2O3·2SiO2) nanofibres by combination of the sol–gel and electrospinning technique is reported. To find out the optimum viscosity of the electrospinning solution for obtaining the high quality mullite nanofibers, solutions containing different amounts of polyvinyl butyral (PVB, 0–8 wt%) and the precursor sol were prepared for the electrospinning process. The precursor sol was made by using proper amounts of aluminium isopropoxide (AIP), hydrated aluminium nitrate (AN) and tetraethylorthosilicate (TEOS). Crystal phase, microstructure and thermal decomposition behaviour of the electrospun mullite nanofibres were investigated by conventional methods of analysis. The optimal amount of PVB in the electrospinning polymeric solutions was found to be between 4 and 6 wt% and the mullite nanofibres obtained as such were pure, smooth and uniform with diameter sizes of 85–130 nm after calcination at 1200 °C.  相似文献   
4.
The effect of bacterial infection on the expression of growth hormone secretagogue receptor (GHS-R) was investigated in periodontal cells and tissues, and the actions of ghrelin were evaluated. GHS-R was assessed in periodontal tissues of rats with and without periodontitis. Human gingival fibroblasts (HGFs) were exposed to Fusobacterium nucleatum in the presence and absence of ghrelin. GHS-R expression was determined by real-time PCR and immunocytochemistry. Furthermore, wound healing, cell viability, proliferation, and migration were evaluated. GHS-R expression was significantly higher at periodontitis sites as compared to healthy sites in rat tissues. F. nucleatum significantly increased the GHS-R expression and protein level in HGFs. Moreover, ghrelin significantly abrogated the stimulatory effects of F. nucleatum on CCL2 and IL-6 expressions in HGFs and did not affect cell viability and proliferation significantly. Ghrelin stimulated while F. nucleatum decreased wound closure, probably due to reduced cell migration. Our results show original evidence that bacterial infection upregulates GHS-R in rat periodontal tissues and HGFs. Moreover, our study shows that ghrelin inhibited the proinflammatory actions of F. nucleatum on HGFs without interfering with cell viability and proliferation, suggesting that ghrelin and its receptor may act as a protective molecule during bacterial infection on periodontal cells.  相似文献   
5.
The aim of study was to develop a novel drug nanocarrier via facile coating of a folate-conjugated dual-responsive copolymer with carboxylic functional groups on the surface of magnetic nanoparticles for the efficient loading and cell-specific targeting of a positively charged anticancer agent. The nanocarrier exhibited many favorable capabilities such as narrow distributed nano-ranged size (~30 nm), high drug loading capacity (~65%), and stimuli-responsive drug release. The results of various cell cytotoxicity studies such as MTT assay, DAPI staining, and flow cytometry concluded that the developed smart nanocarrier paves a way for efficient cancer therapy by the multiple targeting strategies.  相似文献   
6.
Phytic acid–modified layered double hydroxide (Ph‐LDH) was synthesized via coprecipitation method and subsequently was used in polypropylene (PP) by combining with an ammonium polyphosphate (APP) via melt compounding method. The synergistic effect between APP and Ph‐LDH on the thermal stability, flammability, and mechanical properties of the resultant PP composites was investigated by thermogravimetric analysis, limiting oxygen index, vertical burning test (UL‐94), cone calorimeter tests, tensile test, and impact test. Morphologies of the chars obtained from the samples after the cone calorimeter tests were studied by scanning electron microscopy. The combination of APP and Ph‐LDH slightly influenced the impact and tensile properties of PP. Also, the synergistic effect between APP and Ph‐LDH occurred in the cone calorimeter test. Moreover, the combination of APP and Ph‐LDH produced better quality char that effectively suppressed the spread of the flame and volatile and finally extinguished the fire.  相似文献   
7.
Loss-of-function events in tumor suppressor genes (TSGs) contribute to the development and progression of cutaneous malignant melanoma (CMM). Epigenetic alterations are the major mechanisms of TSG inactivation, in particular, silencing by promoter CpG-island hypermethylation. TSGs are valuable tools in diagnosis and prognosis and, possibly, in future targeted therapy. The aim of this narrative review is to outline bona fide TSGs affected by promoter CpG-island hypermethylation and their functional role in the progression of CMM. We conducted a systematic literature review to identify studies providing evidence of bona fide TSGs by cell line or animal experiments. We performed a broad first search and a gene-specific second search, supplemented by reference checking. We included studies describing bona fide TSGs in CMM with promoter CpG-island hypermethylation in which inactivating mechanisms were reported. We extracted data about protein role, pathway, experiments conducted to meet the bona fide criteria and hallmarks of cancer acquired by TSG inactivation. A total of 24 studies were included, describing 24 bona fide TSGs silenced by promoter CpG-island hypermethylation in CMM. Their effect on cell proliferation, apoptosis, growth, senescence, angiogenesis, migration, invasion or metastasis is also described. These data give further insight into the role of TSGs in the progression of CMM.  相似文献   
8.
In this paper, we present an implantable device for intra-cerebral electroencephalography (icEEG) data acquisition and real-time epileptic seizure detection with simultaneous focal antiepileptic drug injection feedback. This implantable device includes a neural signal amplifier, an asynchronous seizure detector, a drug delivery system (DDS) including a micropump, and a hybrid subdural electrode (HSE). The asynchronous detection algorithm is based on data-dependent analysis and validated with Matlab tools. The detector and DDS have a power saving mode. The HSE contacts are made of Platinum (Pt) encapsulated with polydimethylsiloxane (PDMS). Given the heterogeneity of electrographic seizure signals and seizure suppression threshold, the implantable device provides tunable parameters facility through an external transmitter to adapt to each individual's neurophysiology prior to clinical deployment. The proposed detector and DDS were assembled in ? 50 mm and ? 30 mm circular printed circuit boards, respectively. The detector was validated using icEEG recordings of seven patients who had previously undergone an intracranial investigation for epilepsy surgery. The triggering of the DDS was tested and a predefined seizure suppression dose was delivered ~16 s after electrographical seizure onsets. The device's power consumption was reduced by 12% in active mode and 49% in power saving mode compared to similar seizure detection algorithms implemented with synchronous architecture.  相似文献   
9.
Moradi  Marjan  Rastakhiz  Nahid  Ghaedi  Mehrorang  Zhiani  Rahele 《Catalysis Letters》2021,151(6):1653-1662
Catalysis Letters - Nitro-aromatic pollution in industrial waste streams threat wellbeing of water resources. This study investigates the performance of a copper-based nano catalyst to reduce...  相似文献   
10.
Catalysis Letters - Industrial Cu/ZnO/Al2O3 or novel rate catalysts, prepared with a photochemical deposition method, were studied under functional CH3OH synthesis conditions at the set temperature...  相似文献   
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