A Clustering-based Location Privacy Protection Scheme for Pervasive Computing

In pervasive computing environments, Location- Based Services (LBSs) are becoming increasingly important due to continuous advances in mobile networks and positioning technologies. Nevertheless, the wide deployment of LBSs can jeopardize the location privacy of mobile users. Consequently, providing safeguards for location privacy of mobile users against being attacked is an important research issue. In this paper a new scheme for safeguarding location privacy is proposed. Our approach supports location K-anonymity for a wide range of mobile users with their own desired anonymity levels by clustering. The whole area of all users is divided into clusters recursively in order to get the Minimum Bounding Rectangle (MBR). The exact location information of a user is replaced by his MBR. Privacy analysis shows that our approach can achieve high resilience to location privacy threats and provide more privacy than users expect. Complexity analysis shows clusters can be adjusted in real time as mobile users join or leave. Moreover, the clustering algorithms possess strong robustness.Comment: The 3rd IEEE/ACM Int Conf on Cyber, Physical and Social Computing (CPSCom), IEEE, Hangzhou, China, December 18-20, 201

A JNK-Dependent Pathway Is Required for TNFα-Induced Apoptosis

AbstractTumor necrosis factor (TNFα) receptor signaling can simultaneously activate caspase 8, the transcription factor, NF-κB and the kinase, JNK. While activation of caspase 8 is required for TNFα-induced apoptosis, and induction of NF-κB inhibits cell death, the precise function of JNK activation in TNFα signaling is not clearly understood. Here, we report that TNFα-mediated caspase 8 cleavage and apoptosis require a sequential pathway involving JNK, Bid, and Smac/DIABLO. Activation of JNK induces caspase 8-independent cleavage of Bid at a distinct site to generate the Bid cleavage product jBid. Translocation of jBid to mitochondria leads to preferential release of Smac/DIABLO, but not cytochrome c. The released Smac/DIABLO then disrupts the TRAF2-cIAP1 complex. We propose that the JNK pathway described here is required to relieve the inhibition imposed by TRAF2-cIAP1 on caspase 8 activation and induction of apoptosis. Further, our findings define a mechanism for crosstalk between intrinsic and extrinsic cell death pathways

Plasmonic Nanobubbles Rapidly Detect and Destroy Drug-Resistant Tumors

The resistance of residual cancer cells after oncological resection to adjuvant chemoradiotherapies results in both high recurrence rates and high non-specific tissue toxicity, thus preventing the successful treatment of such cancers as head and neck squamous cell carcinoma (HNSCC). The patients' survival rate and quality of life therefore depend upon the efficacy, selectivity and low non-specific toxicity of the adjuvant treatment. We report a novel, theranostic in vivo technology that unites both the acoustic diagnostics and guided intracellular delivery of anti-tumor drug (liposome-encapsulated doxorubicin, Doxil) in one rapid process, namely a pulsed laser-activated plasmonic nanobubble (PNB). HNSCC-bearing mice were treated with gold nanoparticle conjugates, Doxil, and single near-infrared laser pulses of low energy. Tumor-specific clusters of gold nanoparticles (solid gold spheres) converted the optical pulses into localized PNBs. The acoustic signals of the PNB detected the tumor with high specificity and sensitivity. The mechanical impact of the PNB, co-localized with Doxil liposomes, selectively ejected the drug into the cytoplasm of cancer cells. Cancer cell-specific generation of PNBs and their intracellular co-localization with Doxil improved the in vivo therapeutic efficacy from 5-7% for administration of only Doxil or PNBs alone to 90% thus demonstrating the synergistic therapeutic effect of the PNB-based intracellular drug release. This mechanism also reduced the non-specific toxicity of Doxil below a detectable level and the treatment time to less than one minute. Thus PNBs combine highly sensitive diagnosis, overcome drug resistance and minimize non-specific toxicity in a single rapid theranostic procedure for intra-operative treatment

Optimization of degradable temporary plugging material and experimental study on stability of temporary plugging layer

Temporary plugging technology is an important drilling technique for maintaining wellbore stability and resolving lost circulation problems. The key to its success lies in the use of materials that can form a tight and stable “temporary plugging layer” with certain pressure bearing capacity and a permeability close to zero in the loss channel near the wellbore. Experimental studies have been conducted to develop adhesion formulations for optimal temporary plugging materials, as the matching relationship between particle size and fracture width is critical [(0.5−1)/1]. By measuring the permeability of the temporary plugging layer under varying confining pressure with a soap foam flowmeter, researchers have been able to evaluate the effectiveness, degradation, and dosages of temporary plugging agents. It has been shown that a single-particle material, such as a walnut shell, has a smaller permeability than a hyperfine CaCO3 coated temporary plug layer. The latter, however, is less capable of bearing pressure. By combining different materials, such as walnut shells and hyperfine CaCO3 particles, the researchers were able to create a temporary plug layer that had the lowest permeability and did not change much at variable confining pressures. Its pressure-bearing capacity is strong and the temporary plug works well. Experiments have shown that a ratio of 2:1–3:1 of hyperfine CaCO3 and walnut shell particles work well for plugging a fracture system with particles of size 2–3 times the fracture width. It developed an evaluation method for temporary plugging agents, studied their plugging capability and degradation performance for reservoir conversion, and evaluated degradation performance after successful temporary plugging. The temporary plugging rate of the temporary plugging agent increased from 98.10% to 99.81%, and the maximum temporary plugging pressure is 50.39 MPa, which can be completely reduced at 150°C for 4 h, meeting the technical requirements of “dense temporary plugging, two-way pressure bearing” to some extent

Comparison of the Biochemical Composition and Nutritional Quality Between Diploid and Triploid Hong Kong Oysters, Crassostrea hongkongensis

This study is the first systematic comparison of the biochemical composition and nutritional quality between diploid and triploid Hong Kong oysters, Crassostrea hongkongensis. Results showed that in the reproductive season, the glycogen content in five tissues (gill, mantle, adductor muscle, labial palps and gonad) was significantly higher (P < 0.05) in triploids than in diploids, with odds ratios (ORs) of 96.26, 60.17, 72.59, 53.56, and 128.52%, respectively. In the non-reproductive phase, significant differences in glycogen content (P < 0.05) between diploid and triploid oysters existed only in gill and gonad. In both diploid and triploid Hong Kong oysters, quantitative real-time PCR analysis of the glycogen synthesis gene (ChGS) and glycogen phosphorylase gene (ChGP) showed that the gene expression patterns matched the pattern of variation in glycogen content. Moreover, in both the reproductive and the non-reproductive phases, triploid Hong Kong oysters had a well balance of essential amino acids and were thus a well source of high-quality protein. Surprisingly, in both phases, significantly higher (P < 0.05) percentages of four essential fatty acids (α-linolenic acid, linoleic acid, eicosapentaenoic acid, and docosahexaenoic acid) were observed in triploids than in diploids. Additionally, the ratio of n-3/n-6 polyunsaturated fatty acids (PUFAs) was much higher in triploids than that in diploids. Variations in Biochemical composition were consistent with the relative expression of the citrate synthase gene (ChCS) and the α-ketoglutarate dehydrogenase gene (ChKD), which are key enzyme genes of the tricarboxylic acid cycle. Overall, the triploid Hong Kong oyster has a better nutritional value and taste than the diploid in terms of glycogen content, protein quality and fatty acid content

Multidimensional analysis reveals environmental factors that affect community dynamics of arbuscular mycorrhizal fungi in poplar roots

IntroductionPoplar is a tree species with important production and application value. The symbiotic relationship between poplar and arbuscular mycorrhizal fungi (AMF) has a key role in ecosystem functioning. However, there remain questions concerning the seasonal dynamics of the AMF community in poplar roots, the relationship between AMF and the soil environment, and its ecological function.MethodPoplar roots and rhizosphere soil were sampled at the end of April and the end of October. The responses of AMF communities to season, host age, and host species were investigated; the soil environmental factors driving community changes were analyzed.ResultsThe diversity and species composition of the AMF community were higher in autumn than in spring. Season, host age, host species, and soil environmental factors affected the formation of the symbiotic mycorrhizal system and the AMF community. Differences in the communities could be explained by soil pH, total nitrogen, total phosphorus, total potassium, available potassium, and glomalin content.DiscussionThe AMF community was sensitive to changes in soil physicochemical properties caused by seasonal dynamics, particularly total potassium. The change in the mycorrhizal symbiotic system was closely related to the growth and development of poplar trees

Inhibition of Influenza A Virus Replication by TRIM14 via Its Multifaceted Protein–Protein Interaction With NP

Influenza A virus (IAV) is a worldwide ongoing health threat causing diseases in both humans and animals. The interaction between IAV and host is a dynamic and evolving process that influences the pathogenicity and host specificity of the virus. TRIM14, a member of tripartite motif (TRIM) family, has been demonstrated to possess a strong capability of regulating type I interferon and NF-κB induction in host defense against viral infection. In this study, we found that TRIM14 could restrict the replication of IAV in a type I interferon and NF-κB independent manner. Mechanistically, different domains of TRIM14 could selectively interact with the viral nucleoprotein (NP), resulting in disparate influences on the RNP formation and viral replication. In particular, the PRYSPRY domain of TRIM14 exhibited a potent inhibitory activity on NP protein stability and IAV replication. On the contrary, the ΔS2 domain could rather antagonize the function of PRYSPRY domain and promote the IAV RNP formation by stabilizing NP. At the biochemical level, TRIM14-NP interaction could induce the K48-linked ubiquitination and proteasomal degradation of NP. Moreover, due to the rapid degradation of newly synthesized NP, TRIM14 could effectively block the translocation of NP from cytoplasm to nucleus thus further restrain the propagation of IAV in host cells. Taken together, our study has unraveled a previously unknown mechanism of TRIM14 mediated inhibition on RNP formation and influenza virus replication, and provides a new paradigm of complex and multifaceted host–pathogen interaction between ISG and viral protein