Privacy-aware Data Trading

The growing threat of personal data breach in data trading pinpoints an urgent need to develop countermeasures for preserving individual privacy. The state-of-the-art work either endows the data collector with the responsibility of data privacy or reports only a privacy-preserving version of the data. The basic assumption of the former approach that the data collector is trustworthy does not always hold true in reality, whereas the latter approach reduces the value of data. In this paper, we investigate the privacy leakage issue from the root source. Specifically, we take a fresh look to reverse the inferior position of the data provider by making her dominate the game with the collector to solve the dilemma in data trading. To that aim, we propose the noisy-sequentially zero-determinant (NSZD) strategies by tailoring the classical zero-determinant strategies, originally designed for the simultaneous-move game, to adapt to the noisy sequential game. NSZD strategies can empower the data provider to unilaterally set the expected payoff of the data collector or enforce a positive relationship between her and the data collector's expected payoffs. Both strategies can stimulate a rational data collector to behave honestly, boosting a healthy data trading market. Numerical simulations are used to examine the impacts of key parameters and the feasible region where the data provider can be an NSZD player. Finally, we prove that the data collector cannot employ NSZD to further dominate the data market for deteriorating privacy leakage.Comment: 10 pages, 11 figure

Proof of User Similarity: the Spatial Measurer of Blockchain

Although proof of work (PoW) consensus dominates the current blockchain-based systems mostly, it has always been criticized for the uneconomic brute-force calculation. As alternatives, energy-conservation and energy-recycling mechanisms heaved in sight. In this paper, we propose proof of user similarity (PoUS), a distinct energy-recycling consensus mechanism, harnessing the valuable computing power to calculate the similarities of users, and enact the calculation results into the packing rule. However, the expensive calculation required in PoUS challenges miners in participating, and may induce plagiarism and lying risks. To resolve these issues, PoUS embraces the best-effort schema by allowing miners to compute partially. Besides, a voting mechanism based on the two-parties computation and Bayesian truth serum is proposed to guarantee privacy-preserved voting and truthful reports. Noticeably, PoUS distinguishes itself in recycling the computing power back to blockchain since it turns the resource wastage to facilitate refined cohort analysis of users, serving as the spatial measurer and enabling a searchable blockchain. We build a prototype of PoUS and compare its performance with PoW. The results show that PoUS outperforms PoW in achieving an average TPS improvement of 24.01% and an average confirmation latency reduction of 43.64%. Besides, PoUS functions well in mirroring the spatial information of users, with negligible computation time and communication cost.Comment: 12 pages,10 figure

Cost-Efficient Mobile Crowdsensing with Spatial-Temporal Awareness

A cost-efficient deal that can achieve high sensing quality with a low reward is the permanent goal of the requestor in mobile crowdsensing, which heavily depends on the quantity and quality of the workers. However, spatial diversity and temporal dynamics lead to heterogeneous worker supplies, making it hard for the requestor to utilize a homogeneous pricing strategy to realize a cost-efficient deal from a systematic point of view. Therefore, a cost-efficient deal calls for a cost-efficient pricing strategy, boosting the whole sensing quality with less operation (computation) cost. However, state-of-the-art studies ignore the dual cost-efficient demands of large-scale sensing tasks. Hence, we propose a combinatorial pinning zero-determinant (ZD) strategy, which empowers the requestor to utilize a single strategy within its feasible range to minimize the total expected utilities of the workers throughout all sensing regions for each time interval, without being affected by the strategies of the workers. Through turning the worker-customized strategy to an interval-customized one, the proposed combinatorial pinning ZD strategy reduces the number of pricing strategies required by the requestor from O(n^3)to O(n)$ . Besides, it extends the application scenarios of the classical ZD strategy from two-player simultaneous-move games to multiple-heterogeneous-player sequential-move ones, where a leader can determine the linear relationship of the players' expected utilities

Multiplex genomic structure variation mediated by TALEN and ssODN

BACKGROUND: Genomic structure variation (GSV) is widely distributed in various organisms and is an important contributor to human diversity and disease susceptibility. Efficient approaches to induce targeted genomic structure variation are crucial for both analytic and therapeutic studies of GSV. Here, we presented an efficient strategy to induce targeted GSV including chromosomal deletions, duplications and inversions in a precise manner. RESULTS: Utilizing Transcription Activator-Like Effector Nucleases (TALEN) designed to target two distinct sites, we demonstrated targeted deletions, duplications and inversions of an 8.9 Mb chromosomal segment, which is about one third of the entire chromosome. We developed a novel method by combining TALEN-induced GSV and single stranded oligodeoxynucleotide (ssODN) mediated gene modifications to reduce unwanted mutations occurring during the targeted GSV using TALEN or Zinc finger nuclease (ZFN). Furthermore, we showed that co-introduction of TALEN and ssODN generated unwanted complex structure variation other than the expected chromosomal deletion. CONCLUSIONS: We demonstrated the ability of TALEN to induce targeted GSV and provided an efficient strategy to perform GSV precisely. Furthermore, it is the first time to show that co-introduction of TALEN and ssODN generated unwanted complex structure variation. It is plausible to believe that the strategies developed in this study can be applied to other organisms, and will help understand the biological roles of GSV and therapeutic applications of TALEN and ssODN. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1471-2164-15-41) contains supplementary material, which is available to authorized users

Privacy-Aware Data Trading

The growing threat of personal data breach in data trading pinpoints an urgent need to develop countermeasures for preserving individual privacy. The state-of-the-art work either endows the data collector with the responsibility of data privacy or reports only a privacy-preserving version of the data. The basic assumption of the former approach that the data collector is trustworthy does not always hold true in reality, whereas the latter approach reduces the value of data. In this paper, we investigate the privacy leakage issue from the root source. Specifically, we take a fresh look to reverse the inferior position of the data provider by making her dominate the game with the collector to solve the dilemma in data trading. To that aim, we propose the noisy-sequentially zero-determinant (NSZD) strategies by tailoring the classical zero-determinant strategies, originally designed for the simultaneous-move game, to adapt to the noisy sequential game. NSZD strategies can empower the data provider to unilaterally set the expected payoff of the data collector or enforce a positive relationship between her and the data collector's expected payoffs. Both strategies can stimulate a rational data collector to behave honestly, boosting a healthy data trading market. Numerical simulations are used to examine the impacts of key parameters and the feasible region where the data provider can be an NSZD player. Finally, we prove that the data collector cannot employ NSZD to further dominate the data market for deteriorating privacy leakage

Does government expenditure affect environmental quality? Empirical evidence using Chinese city-level data

With rapid economic development, the Chinese government expenditures at various levels have increased sufficiently. At the same time, the environmental pollution in China has deteriorated significantly. In this study, the city-level panel data of 106 Chinese cities over the 2002-2014 period are utilized to investigate the impacts of government expenditure on the emissions of three typical pollutants. Specifically, the total effects are divided into two types: direct effects, through which government expenditure affects pollution directly; and indirect effects, which refer to the indirect influences of government expenditure on environmental pollution through its impacts on GDP per capita. To control for potential endogeneity and introduce dynamics, the generalized method of moments (GMM) method is utilized. The estimation results indicate that the total effects of government expenditure on these three pollutants are very different: for sulfur dioxide (502), soot and chemical oxygen demand (COD), the total effects are decreasing, inverted-U and U-shaped, respectively. Furthermore, the indirect effects dominate the direct effects. (C) 2017 Elsevier Ltd. All rights reserved

Simultaneous measurement of Re-Os and S isotopic compositions of sulfur-bearing minerals using a Carius tube digestion-based N-TIMS and MC-ICP-MS approach

This study reports an improved procedure for the simultaneous determination of Re-Os and S isotopic compositions of sulfur-bearing minerals using negative thermal ionization mass spectrometry (N-TIMS) and multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS), respectively. This approach uses a Carius tube digestion technique during inverse aqua regia digestion to avoid the incomplete decomposition of sulfide minerals and the partial loss of S and Os during acid digestion. The sequential separation and purification of S and Re from sample matrix elements is undertaken after Os separation by CCl4 solvent extraction and utilizes a two-stage tandem column setup using cation and anion exchange resins. Sulfur is not adsorbed onto either of the cation or anion exchange resin columns and can be directly eluted using 0.1 mol L-1 HNO3, whereas Re is adsorbed onto the anion exchange resin column. This approach allowed the quantitative recovery of S (99.8%) and Re (99.7%), and the efficient removal of matrix elements from the final purified sample. The S-34 values of IAEA S-2, S-3, and IAPSO seawater standards determined during this study (calibrated using the IAEA S-1 standard) are consistent with the certified values and are of higher precision than the values obtained using conventional analytical techniques. Our approach can also be used with different kinds of sulfide minerals. This combined Re-Os-S isotopic analysis provides useful information on the timing of ore deposit formation and constrains the source of the ore-forming fluid material. This approach also allows the determination of Re-Os and S isotopic compositions of single sample digestion, thereby avoiding problems with sample heterogeneity that can arise when comparing S and Re-Os isotopic data generated by conventional approaches

Stroke controllable style transfer based on dilated convolutions

Transferring a photo to a stylised image with beautiful texture has become one of the most popular topics in computer vision and the application of image processing. Controlling the stroke size of the texture is one of the challenging problems in this task. Recent representative methods for such problem introduce a pyramid model to regulate receptive fields in the network. Meanwhile, dilated convolutions are proved to be a very efficient way to adjust receptive fields without losing resolution. By combining the advantages of both approaches and making special optimisation for VGG19 model for style transfer tasks, the authors propose to exploit dilated convolutions to extract texture information endowing the network with stroke controllable. Several sets of contrast experiments were conducted and results show that their algorithm can generate more attractive stylisation images and control stroke size flexibly. It demonstrates the superiority of applying dilated convolutions as a texture extraction method for maintaining more texture information and controlling stroke size

Influence of extent of surgical resection on post-hepatectomy shoulder pain: an observational study

Abstract Shoulder pain frequently follows hepatectomy. However, the influence of surgical procedures on shoulder pain is unclear. In this observational study, patients who underwent hepatectomy were enrolled in Shanghai Cancer Center. Shoulder pain and surgical pain were assessed using the numeric rating scale 2 days after surgery. The incidence of shoulder pain was the outcome of the cohort study. Nested case–control analyses were further applied. Three hundred and twelve patients were finally enrolled in this study. Nested case–control analysis showed that there were no significant differences in the number of surgical segments between the two groups (P = 0.09). In addition, minor hepatectomy did not reduce the incidence of shoulder pain compared with major hepatectomy (P = 0.37). The drainage volume within 2 days after surgery was significantly more in those patients with shoulder pain (P = 0.017). In open surgery, surgical sites involving the right anterior lobe (OR (95% CI) 2.021 (1.075, 3.802), P = 0.029) and right posterior lobe (OR (95% CI) 2.322 (1.193, 4.522), P = 0.013) were both independent risk factors for shoulder pain. Left shoulder pain also occurred in patients who did not receive left lateral hepatectomy. The preventive phrenic nerve block was not suitable for post-hepatectomy shoulder pain. Stronger preventative intervention should be used in those high-risk patients