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41.
Recent advances in hardware technology have led to the development of low cost, power efficient and more feature rich devices that are amongst the most critical parts of communication networks. These devices or sensors can now sense data with more accuracy, process it by themselves and send it to the neighboring node or the sink node. However, robust and reliable security mechanisms are not yet properly implemented on these sensors due to their limited energy and computation power. Sensors also play a very important role in eHealthcare systems where ubiquitous patient monitoring is performed. As data is generated from the sensor nodes, reliable, secure and attack-resistant data acquisition and transmission is important for an efficient eHealthcare systems. This survey focuses on security issues of sensors data acquisition and transmission protocols, describing their main security features and comparing them in the context of a secure eHealthcare system. A taxonomy of open issues and future challenges is also discussed with respect to specific security metrics described in the paper.  相似文献   
42.
Supercritical fluid extraction (SFE) using carbon dioxide (CO2) and liquid CO2 using Soxhlet (CO2-Soxhlet) extraction were employed to extract three (3) antidiabetic compounds viz. stigmasterol, quercetin, and avicularin from Mimosa pudica. Various extraction parameters were studied. Extracts were analyzed pharmacologically, qualitatively and quantitatively to ascertain enrichment levels. All three antidiabetic compounds were effectively enriched under optimized conditions of temperature 60°C, pressure 40 MPa, co-solvent ratio 30%, and CO2 flow rate of 5 ml min?1. SFE was found to be the better method for enrichment of the antidiabetic compounds than the CO2-Soxhlet method. Extraction conditions were seen to affect the enrichment of desired compounds.  相似文献   
43.
Stevia rebaudiana (Bertoni) leaves consist of stevioside and rebaudioside-A (Reb-A). This research sought to improve extraction of target steviol glycosides from stevia leaf powder using response surface methodology (RSM) and artificial neural networking (ANN) under these independent variables: ethanol concentration, X1 (0–100%), extraction temperature, X2 (55–75°C), and extraction time, X3 (45–75 min). ANN outperformed as potential alternative to RSM in predicting optimum conditions. Maximum responses were obtained at 100% X1, 55°C X2, and 60 min X3. Heat reflux extraction proved superior to maceration extraction in terms of higher extraction yields with reduced energy consumption and CO2 emission.  相似文献   
44.
Subcritical carbon dioxide Soxhlet extraction of biologically active compounds from Clincanthus nutans was investigated by full factorial design to identify and optimize the factors (particle size and co-solvent) affecting extract yield, antioxidant activity, total phenolic content, total flavonoid content, and α-glucosidase inhibitory activity. An average of 3.103% yield, 98.90% antioxidant activity, 49.40 mg/g (GAE) TPC, 43.76 mg/g (RE), and 88.58% AGI activity can be achieved using the optimum levels of independent variables. The GC-Q-TOF MS identification of optimized extract shown that different classes of phytoconstituents were successfully separated by CO2-Soxhlet to produce potential antioxidant and α-glucosidase inhibitory activity.  相似文献   
45.
Baek  Mi-eun  Ameer  Kashif  Jo  Yunhee  Chung  Namhyeok  Choi  Minji  Kim  Jung-ok  Won  Jaehee  Lee  Sang-Han  Kwon  Joong-Ho 《Food science and biotechnology》2020,29(5):705-715
Food Science and Biotechnology - Medicinal herbs comprise of heavy microbial contaminations. This study aimed to assess microbial hazards including foodborne pathogens in 20 commercial medicinal...  相似文献   
46.
It is difficult to treat allergic diseases including asthma completely because its pathogenesis remains unclear. House dust mite (HDM) is a critical allergen and Toll-like receptor (TLR) 4 is a member of the toll-like receptor family, which plays an important role in allergic diseases. The purpose of this study was to characterize a novel allergen, Der f 38 binding to TLR4, and unveil its role as an inducer of allergy. Der f 38 expression was detected in the body and feces of Dermatophagoides farinae (DF). Electron microscopy revealed that it was located in the granule layer, the epithelium layer, and microvilli of the posterior midgut. The skin prick test showed that 60% of allergic subjects were Der f 38-positive. Der f 38 enhanced surface 203c expression in basophils of Der f 38-positive allergic subjects. By analysis of the model structure of Der p 38, the expected epitope sites are exposed on the exterior side. In animal experiments, Der f 38 triggered an infiltration of inflammatory cells. Intranasal (IN) administration of Der f 38 increased neutrophils in the lung. Intraperitoneal (IP) and IN injections of Der f 38 induced both eosinophils and neutrophils. Increased total IgE level and histopathological features were found in BALB/c mice treated with Der f 38 by IP and IN injections. TLR4 knockout (KO) BALB/c mice exhibited less inflammation and IgE level in the sera compared to wild type (WT) mice. Der f 38 directly binds to TLR4 using biolayer interferometry. Der f 38 suppressed the apoptosis of neutrophils and eosinophils by downregulating proteins in the proapoptotic pathway including caspase 9, caspase 3, and BAX and upregulating proteins in the anti-apoptotic pathway including BCL-2 and MCL-1. These findings might shed light on the pathogenic mechanisms of allergy to HDM.  相似文献   
47.
Kashif Ishaque 《Solar Energy》2011,85(9):2349-2359
To accurately model the PV module, it is crucial to include the effects of irradiance and temperature when computing the value of the model parameters. Considering the importance of this issue, this paper proposes an improved modeling approach using differential evolution (DE) method. Unlike other PV modeling techniques, this approach enables the computation of model parameters at any irradiance and temperature point using only the information provided by the manufacturer’s data sheet. The key to this improvement is the ability of DE to simultaneously compute all the model parameters at different irradiance and temperature. To validate the accuracy of the proposed model, three PV modules of different types (multi-crystalline, mono-crystalline and thin-film) are tested. The performance of the model is evaluated against the popular single diode model with series resistance Rs. It is found that the proposed model gives superior results for any irradiance and temperature variations. The modeling method is useful for PV simulator developers who require comprehensive and accurate model for the PV module.  相似文献   
48.
In comparison with the initial values, acidity and 5‐(hydroxy‐methyl)‐2‐furaldehyde (HMF) values of all honey samples increased during storage. The total phenol contents of honey were decreased from 286.2 to 108.6 mg GAE/kg during 9 months of storage in white colored container. In addition, total phenol contents of honey sample stored in tin container ranged from 294.7 to 258.6 mg GAE/kg (p < .05). While radical scavenging activity values of honey samples stored in amber colored container during storage are measured as 78.6 g/L, IC50, 77.9 g/L, IC50, and 76.1 g/L, IC50, these activity values were determined as 84.9 g/L, IC50, 80.7 g/L, IC50, and 75.2 g/L, IC50 in tin container (p < .05), respectively. While acidity values of honey samples stored in white bottle range from 23.6 (3th month) to 25.7% (9th month), it varied from 20.6 (3th month) to 21.6% (9th month) in honey sample stored in amber colored container during storage.

Practical applications

Different honeys are produced in different parts of Turkey. The known honeys are pine, citrus, and chestnut honey. Various flower honeys are produced in these and other regions. HMF formation is considered as a bed result of storage and heating.  相似文献   
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