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The current router security issues focus on the mining and utilization of memory-type vulnerabilities, but there is low interest in detecting backdoors.Hard-coded backdoor is one of the most common backdoors, which is simple and convenient to set up and can be implemented with only a small amount of code.However, it is difficult to be discovered and often causes serious safety hazard and economic loss.The triggering process of hard-coded backdoor is inseparable from string comparison functions.Therefore, the detection of hard-coded backdoors relies on string comparison functions, which are mainly divided into static analysis method and symbolic execution method.The former has a high degree of automation, but has a high false positive rate and poor detection results.The latter has a high accuracy rate, but cannot automate large-scale detection of firmware, and faces the problem of path explosion or even unable to constrain solution.Aiming at the above problems, a hard-coded backdoor detection algorithm based on string text semantic conflict (Stect) was proposed since static analysis and the think of stain analysis.Stect started from the commonly used string comparison functions, combined with the characteristics of MIPS and ARM architectures, and extracted a set of paths with the same start and end nodes using function call relationships, control flow graphs, and branching selection dependent strings.If the strings in the successfully verified set of paths have semantic conflict, it means that there is a hard-coded backdoor in the router firmware.In order to evaluate the detection effect of Stect, 1 074 collected device images were tested and compared with other backdoor detection methods.Experimental results show that Stect has a better detection effect compared with existing backdoor detection methods including Costin and Stringer: 8 hard-coded backdoor images detected from image data set, and the recall rate reached 88.89%.

Soil microorganisms play important roles in promoting soil ecosystem restoration, but much of the current research has been limited to changes in microbial community structure in general, and little is known regarding the soil physicochemical property and microbial community structure. In this study, four organic fertilizers were first prepared based on tea oil camellia shell (TOCS). Our findings indicate that the application of BOFvo increased both total pore volume and BET surface area of the rhizosphere soils, as well there was a remarkable enhancement in total organic matter (TOM), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), total potassium (TK), and available potassium (AK) contents of the rhizosphere soils. Meanwhile, in comparison to the CK and CF groups, the utilization of BOFvo led to a substantial increase in both average yield and fruiting rate per plant at maturity, as well resulted in a significant increase in TN and TP contents of tea oil camellia leaves. Furthermore, our findings suggest that the application of TOCS-based organic fertilizers significantly enhances the microbial diversity in the rhizosphere soils with Proteobacteria and Ascomycota being the dominant bacterial and fungal phyla, respectively, and Rhodanobacter and Fusarium being the dominant bacterial and fungal genus, respectively. Redundancy analysis (RDA) indicates that the physicochemical characteristics of TOCS-based organic fertilizers had a significant impact on the composition and distribution of microbial communities in the rhizosphere soils. This study will facilitate the promotion and application of TOCS-based organic fertilizers, thereby establishing a foundation for the reuse of tea oil camellia waste resources.

In order to definite the effects of the extraction and cold pressing methods on the nutrition of Camellia oleifera oil. The fatty acid composition, micronutrient, nutrient elements of Camellia oleifera oil were analyzed, then the quality of oil was evaluated by principal component factor analysis to study the effect of cold pressing and extraction methods on the nutritional components of Camellia oleifera oil, which from five main producing were as of Guizhou province were studied in this paper. The results showed that fatty acid composition and content of Camellia oleiformis oil prepared by pressing and extraction method were not significantly different(P>0.05), the unsaturated fatty acids accounted for about 90% of the total fatty acids, and oleic acid was the highest, about 79%~81%, followed by linoleic acid, about 5%~8%. The average content of five main producing were as oil made by pressing method, its squalene and Vitamin E was higher about 12.56%, 115.76% than that of extraction method, respectively. There was a significant difference between different regions of Camellia oleifera oil content of nutrient elements(PK>Na>Mg>Fe>Mn>Zn>Ni>Cu>Se. The contents of Ca, Fe, Ni, Cu, Zn and Se in the cold pressed oil were higher than extraction method oil, including content of Ca, Fe, Zn were higher 18.77%, 461.66%, 78.09% and Ni, Cu and Se were not detected in the extraction method. The extraction method was beneficial to obtain higher 66.75%, 48.24%, 79.16%, 75.46% contents of K, Na, Mg and Mn than cold pressing method, respectively. The results indicated that the local Hongqiu oleotea of Ceheng and Camellia meiocarpa of Songtao had the best quality of the combined scores were 0.902 and 0.560, respectively, followed by the local Camellia of Liping and Tianzhu Xianglin series, followed by Xianglin 210 Camellia of Yuping. Principal component factor analysis showed that the comprehensive score of pressing method was higher than extraction method that of when only the fatty acid composition, squalene, vitamin E and elements nutritions were considered. This study enriched the basic theory of quality analysis of Camellia oleifera and provided new methods and ideas for scientific evaluation of quality of Camellia oleifera in Guizhou.

The purpose of this study was to fabricate a low-cost and eco-friendly adsorbent using bamboo biochar (BB), a kind of charcoal composed of high Brunauer–Emmett–Teller surface area and variety of functional groups, and chitosan as substrates for remediation of Cd(II) in Cd(II) contaminated water and characterized the functional group characteristics, surface morphology, and Cd(II) adsorption effect using the Fourier transform infrared (FT-IR), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometer (EDS). Results showed that chitosan-modified bamboo biochar (CBB) provided more active adsorption sites (such as –NH2, –COOH, –OH, and C=O) on the surface to enhance the Cd(II) removal efficiency in Cd(II) contaminated wastewater. Meanwhile, the optimal pH, contact time, and dose of CBB on the Cd(II) removal efficiency are 7, 120 min, and 600 mg, respectively. In addition, the adsorption isotherm results revealed that the possible adsorption mechanisms might include surface adsorption, electrostatic adsorption, and ion exchanges. Furthermore, the maximum adsorption capacity (Qm) values predicted from the Langmuir model were 37.74 and 93.46 mg/g for BB and CBB, respectively, also indicating a potential application of CBB in practical wastewater. Desorption and regeneration of CBB were attained simultaneously and the results showed that even after five cycles of adsorption-elution, the adsorption and desorption of CBB exhibited a slight decline and still reached at 71.70% and 65.92%. Results from this study would provide a reference to functionalized CBB for Cd(II) adsorption in contaminated water.

Abstract Bamboo is readily discolored by mold fungi, which greatly limits its applications. An effective antifungal agent, copper(II) chloride (CuCl2)-grafted silica gel, was prepared by a sol–gel process using tetraethoxysilane (TEOS)/3-aminopropyltriethoxysilane (APTES) mixtures. The elemental composition and the chemical combinations of homogeneous sol mixture (HSM) and bamboo were determined via Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy with energy-dispersive X-ray spectrometry (SEM–EDS). The mold resistance of bamboo treated with HSM, alkaline copper quat (ACQ), chromated copper arsenate (CCA), and purified water was characterized by an indoor mold test. The micro-morphology of bamboo treated with HSM was investigated using scanning electron microscopy (SEM). HSM penetrated into the bamboo vessels, and formed xerogels, which was able to coordinate copper(II) cations. SEM–EDS investigations suggest that Si–O–Cu linkages may be formed through an exchange reaction between silanol groups and copper complexes. The bamboo samples treated with HSM showed highly efficient mold resistance due to a good penetration of HSM. Furthermore, no fungal hyphae were found in the structure of HSM-treated bamboo after a 5-week mold test. The copper complexes grafted to silica gel developed in this work provide an efficient antifungal agent for a wide range of potential applications in bamboo protection.

In gastric carcinoma, the nuclear factor-B (NF-B) signaling pathway is highly active, and the constitutive activation of NF-B prompts malignant cell proliferation. MicroRNAs are considered to be important mediators in the regulation of the NF-B signaling pathway. The present study predominantly focussed on the effects of microRNA (miR)-19a on NF-B activation. Reverse transcription-quantitative polymerase chain reaction was used to quantify the relative levels of miR-19a in gastric carcinoma cells. MTT assays were used to determine the effect of miR-19a on cellular proliferation. To detect the activation of NF-B, western blotting was performed to measure the protein levels of NF-B and the products of its downstream target genes. To define the target genes, luciferase reporter assays were used. miR-19a was found to be markedly upregulated in gastric carcinoma cells. The overexpression of miR-19a resulted in proliferation and enhanced migratory capabilities of the MGC-803 gastric carcinoma cell line. The results of the western blot analysis demonstrated that the protein levels of p65 increased when the MGC-803 cells were transfected with miR-19a mimics. In addition, the downstream target genes of miR-19a, including intercellular adhesion molecule, vascular cell adhesion molecule and monocyte chemoattractant protein-1, were upregulated. The results of the luciferase assay indicated that IB-a was the target gene of miR-19a. Therefore, the results of the present study suggested that miR-19a enhances malignant gastric cell proliferation by constitutively activating the NF-B signaling pathway. [ABSTRACT FROM AUTHOR]