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101.
Naser Nabifarkhani Mehdi Sharifani Amir Daraei Garmakhany Ebrahim Ganji Moghadam Alireza Shakeri 《Food Science & Nutrition》2015,3(4):349-354
Sweet cherry is one of the most appreciated fruit by consumers since it is an early season fruit and has an excellent quality. In this study effect of active nano composite formed from chitosan (as a matrix material), nano cellulose fiber (1% concentration) and Thyme oils (Tymus Vulgaris L) at 1% concentration on fruits quality was investigated. Treated fruits were stored at 1°C for 5 weeks and changes of different qualities attributes including weight loss, total acidity, TSS, anthocyanin, total sugar and malic acid content (by high performance liquid chromatography (HPLC) method) were measured each week. Results showed that nano composite and Thyme oil significantly affect fruit's water retention and so decrease fruit weight loss and preserve anthocyanin (P < 0.05). None of applied treatments had any significant effects in comparison with control in regard to acidity while total sugar content and TSS significantly affected by treatment compared to control samples. Result of HPLC analysis showed that there was no significant difference between different treatment and control sample in term of malic acid concentrations during storage period but increase storage time lead to increase malic acid concentration in all treatments. For conclusion it can be Saied that fruits coating with nano‐composite, lead to increase fruit shelf life, better appearance and prevents fungal growth that may be due to creation of an active packaging by these compounds. 相似文献
102.
103.
Behrouz Shahgholi Ghahfarokhi Naser Movahhedinia 《Wireless Communications and Mobile Computing》2011,11(6):723-741
Growing demands for pervasive and ubiquitous services over wireless mobile networks and evolution of such networks towards heterogeneous solutions have emphasized the necessity of more intelligent handoff decisions. The existing handoff management methods in the literature are mostly using signal strength measurements and other link quality evaluations not addressing the knowledge about context of mobile devices, users and networks. Recently, context‐aware handoff management has been considered as a novel candidate for fourth generation (4G) wireless technology. In this paper, user perceived quality of service has been considered in addition to traditional contexts such as user preferences, application requirements, network parameters and link quality for decision making. User perceived quality (UPQ) has been employed as a trigger source, in addition to link layer triggers which are emerged using media independent handover (MIH) event service. This paper presents a policy based mechanism for handoff decision making where fuzzy petri nets (FPNs) have been utilized as its evaluation algorithm. A case study has been provided by simulations to show the usability and user level satisfaction. Simulation results show superior performance in terms of UPQ, jitter and packet delivery measures. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
104.
Qureshi N Wang S Lowther MA Hawkins AR Kwon S Liddle A Bokor J Schmidt H 《Nano letters》2005,5(7):1413-1417
Optical studies of nanoscale magnets promise access to ultrafast magnetization dynamics but are challenging because of limited spatial resolution. We demonstrate that cavity enhancement of the magnetooptical Kerr effect increases the sensitivity in nanomagnetooptics significantly. Magnetization switching in individual single-domain magnets in both far-field and near-field Kerr microscopy is observed, and scaling laws are determined. Near-field signals remain nearly constant with reduced magnet diameter, indicating favorable scaling of near-field magnetooptics into the deep nanometer range. 相似文献
105.
Shadi Moazzeni Mohammad Reza Khayyambashi Naser Movahhedinia Franco Callegati 《International Journal of Communication Systems》2020,33(9)
This paper presents a method to improve the reliability and fault tolerance of distributed software‐defined networks. This method is called “BIRDSDN (Byzantine‐Resilient Improved Reliable Distributed Software‐Defined Networks).” In BIRDSDN, a group communication is implemented among the controllers of the whole clusters. This method can detect the crash failure and Byzantine failure of any controller and undertakes a fast detection and recovery scheme to select the controllers to take over the orphan switches. BIRDSDN takes into account the reliability of the nodes considering the failure probability of intracluster and intercluster links, topology, load, and latency. The numerical results show that this approach performs better than the other approaches regarding failure detection, recovery, latency, throughput, reliability, and packet loss. 相似文献
106.
Hui Tang Wageh Sobhy Darwish Waleed Rizk El‐Ghareeb Naser A. Al‐Humam Lin Chen Rui‐Min Zhong Zi‐Jun Xiao Jin‐Kui Ma 《Food Science & Nutrition》2020,8(4):2094-2101
This study aimed firstly at the investigation of the microbial status of the camel meat and edible offal including liver, kidneys, lungs, rumen, and duodenum distributed at local markets of Egypt. Total plate count, total psychrophilic counts, total Enterobacteriaceae count, the most probable number of coliforms, and total mold counts were monitored at the collected samples. The produced biogenic amines (BA) in the camel meat and offal were further estimated. An experimental trial to investigate the antimicrobial potentials of either nisin, gingerol, or an equal mixture of both using camel muscle as a food matrix was conducted. The achieved results declared a high microbial load in the camel meat and the offal. Duodenum and rumen had the highest microbial counts followed by lungs, kidneys, liver, and muscle, respectively. Similarly, duodenum and rumen had the highest levels of BA, including tyramine, spermine, putrescine, cadaverine, and histamine. Both of nisin and ginger showed significant antimicrobial properties in a concentration‐dependent manner. Thus, efficient hygienic measures during the handling of camel meat are highly recommended. In addition, using nisin, gingerol, or a mixture of both is an efficient strategy for improving the microbiological quality of the camel meat. 相似文献
107.
Md Shariful Islam Abu Naser Zafar Ullah Shristi Mainali Md. Akhter Imam Md Imran Hasan 《Food Science & Nutrition》2020,8(9):4685-4695
Stunting is a major problem in Bangladesh, with a prevalence of 31% in 2017. The prevalence of stunting in children aged under two has reduced by only 6% since 2004. After children reach 2 years of age, the consequences of stunting become almost irreversible. This paper seeks to examine and analyze the determinants associated with stunting during the first 1,000 days of life in Bangladesh to assist in developing evidence‐based interventions in Bangladesh. A literature review was conducted comprehensively on all relevant peer‐reviewed and gray literature of studies conducted in Bangladesh. The existing literature was searched and examined using the World Health Organization (WHO) conceptual framework for stunting. Evidence indicates that low maternal weight, lack of maternal education, severe food insecurity, lack of access to suitable nutrition, nonexclusive breastfeeding, pathogen‐specific diarrhea, and low weight and height at birth are associated with early childhood stunting in Bangladesh. The relation of the quality of drinking water with stunting is not clear in Bangladesh. Literature about the association between stunting and determinants such as the political economy, education systems, and agriculture and food systems is not found. This synthesis shows that the factors of stunting are multifaceted. As such, a multi‐sectoral approach is essential in Bangladesh, employing evidence‐based interventions to address the determinants that contribute to the risk of stunting to achieve the global nutrition target by 2025. 相似文献
108.
One of the basic challenges in content‐centric networking (CCN) is how to optimize the overall energy consumption of content transmission and caching. Furthermore, designing an appropriate caching policy that considers both energy consumption and quality of service (QoS) is a major goal in green CCN. In this paper, the problem of minimizing the total CCN energy consumption while being aware of the end‐to‐end delay is formulated as an integer linear programming model. Since it is an Non‐deterministic Polynomial‐time (NP)‐hard problem, the Markov approximation method for an energy‐delay aware caching strategy (MAEDC) is proposed through a log‐sum‐exp function to find a near‐optimal solution in a distributed manner. The numerical results show that the MAEDC achieves near‐optimal energy consumption with better delay profile compared with the optimal solution. Moreover, due to the possibility of distributed and parallel processing, the proposed method is proper for the online situation where the delay is a crucial issue. 相似文献
109.
Mohammad Alibakhshi‐Kenari Mohammad Naser‐Moghadasi Ramazan Ali Sadeghzadeh Bal Singh Virdee 《国际射频与微波计算机辅助工程杂志》2016,26(1):88-96
Two planar antennas based on metamaterial unit‐cells are designed, fabricated, and tested. The unit‐cell configuration consists of H‐shaped or T‐shaped slits and a grounded spiral. The slits essentially behave as series left‐handed capacitance and the spiral as a shunt left‐handed inductance. The unit‐cell was modeled and optimized using commercial 3D full‐wave electromagnetic simulation tools. Both antennas employ two unit‐cells, which are constructed on the Rogers RO4003 substrate with thickness of 0.8 mm and εr = 3.38. The size of H‐shaped and T‐shaped unit cell antennas are 0.06λ0 × 0.02λ0 × 0.003λ0 and 0.05λ0 × 0.02λ0 × 0.002λ0, respectively, where λ0 is the free–space wavelength. The measurements confirm the H–shaped and T–shaped unit‐cell antennas operate across 1.2–6.7 GHz and 1.1–6.85 GHz, respectively, for voltage standing wave ratio (VSWR) < 2, which correspond to fractional bandwidth of ～140% and ～ 145%, respectively. The H‐shaped unit‐cell antenna has gain and efficiency of 2–6.8 dBi and 50–86%, respectively, over its operational range. The T‐shaped unit‐cell antenna exhibits gain and efficiency of 2–7.1 dBi and 48–91%, respectively. The proposed antennas have specifications applicable for integration in UWB wireless communication systems and microwave portable devices. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:88–96, 2016. 相似文献
110.
Crohn’s Disease (CD) and Rheumatoid Arthritis (RA) share some single nucleotide polymorphisms (SNPs) in protein tyrosine phosphatase non-receptor types 2 and 22 (PTPN2/22). Recently, we reported that clinical samples from CD and RA patients associated with PTPN2:rs478582 or PTPN22:rs2476601 genotypes were linked to overactive immune response and exacerbation of inflammation. Here, we investigated in vitro the effects of these SNPs in Jurkat T-cells using CRISPR-Cas9. All cells were evaluated for PTPN22/22 loss of function and effects on cell response. We measured gene expression via RT-qPCR and cytokines by ELISA. We also measured cell proliferation using a BrdU labeling proliferation ELISA, and T-cell activation using CD-25 fluorescent immunostaining. In PTPN2 SNP-edited cells, PTPN2 expression decreased by 3.2-fold, and proliferation increased by 10.2-fold compared to control. Likewise, expression of PTPN22 decreased by 2.4-fold and proliferation increased by 8.4-fold in PTPN22 SNP-edited cells. IFN-γ and TNF-α secretions increased in both edited cell lines. CD25 expression (cell activation) was 80.32% in PTPN2 SNP-edited cells and 85.82% in PTPN22 SNP-edited cells compared to 70.48% in unedited Jurkat T-cells. Treatment of PTPN2 and PTPN22-edited cells with a maximum 20 μM spermidine restored PTPN2/22 expression and cell response including cell proliferation, activation, and cytokines secretion. Most importantly, the effect of spermidine on edited cells restored normal expression and secretion of IFN-γ and TNF-α. The data clearly demonstrated that edited SNPs in PTPN2 or PTPN22 were associated with reduced gene expression, which resulted in an increase in cell proliferation and activation and overactive immune response. The data validated our earlier observations in CD and RA clinical samples. Surprisingly, spermidine restored PTPN2/22 expression in edited Jurkat T-cells and the consequent beneficial effect on cell response and inflammation. The study supports the use of polyamines dietary supplements for management of CD and in RA patients. 相似文献