EMPSI:Efficient multiparty private set intersection(with cardinality)

Multiparty private set intersection(PSI)allows several parties,each holding a set of elements,to jointly compute the intersection without leaking any additional information.With the development of cloud computing,PSI has a wide range of applications in privacy protection.However,it is complex to build an efficient and reliable scheme to protect user privacy.To address this issue,we propose EMPSI,an efficient PSI(with cardinality)protocol in a multiparty setting.EMPSI avoids using heavy cryptographic primitives(mainly rely on symmetric-key encryption)to achieve better performance.In addition,both PSI and PSI with the cardinality of EMPSI are secure against semi-honest adversaries and allow any number of colluding clients(at least one honest client).We also do experiments to compare EMPSI with some state-of-the-art works.The experimental results show that proposed EMPSI(-CA)has better performance and is scalable in the number of clients and the set size.

IXT: Improved searchable encryption for multi-word queries based on PSI

Oblivious Cross-Tags(OXT)[1]is the first efficient searchable encryption(SE)protocol for conjunctive queries in a single-writer single-reader framework.However,it also has a trade-off between security and efficiency by leaking partial database information to the server.Recent attacks on these SE schemes show that the leakages from these SE schemes can be used to recover the content of queried keywords.To solve this problem,Lai et al.[2]propose Hidden Cross-Tags(HXT),which reduces the access pattern leakage from Keyword Pair Result Pattern(KPRP)to Whole Result Pattern(WRP).However,the WRP leakage can also be used to recover some additional contents of queried keywords.This paper proposes Improved Cross-Tags(IXT),an efficient searchable encryption protocol that achieves access and searches pattern hiding based on the labeled private set intersection.We also prove the proposed labeled private set intersection(PSI)protocol is secure against semi-honest adversaries,and IXT is-semi-honest secure(is leakage function).Finally,we do experiments to compare IXT with HXT.The experimental results show that the storage overhead and computation overhead of the search phase at the client-side in IXT is much lower than those in HXT.Meanwhile,the experimental results also show that IXT is scalable and can be applied to various sizes of datasets.

岩溶洞穴苔藓群落特征及其对重金属污染的指示意义:以贵州织金洞为例

岩溶洞穴的开发与利用导致的重金属污染严重威胁洞穴环境及地下水,因此对洞穴环境的监测具有重要的现实意义。本文通过对典型的暗河型溶洞贵州织金洞内的苔藓群落特征及其重金属污染状况进行研究,拟揭示苔藓群落对洞穴重金属污染的指示意义。共发现苔藓群落类型34个,苔藓植物种类20科33属49种,含苔类8科8属12种,藓类12科25属37种。优势科为丛藓科、凤尾藓科和提灯藓科,物种占比率分别为16%、14%、14%。Hg污染超标倍数最高达59.45倍,在距洞口不同深度均远高于Cr和Zn,说明洞内Hg污染较为严重。苔藓群落指标随着重金属污染含量的上升总体呈下降趋势。所测定的重金属中基质Hg含量与苔藓群落指标的拟合程度最好,与其对应的苔藓群落指标均呈显著负相关关系(P <0.05),说明苔藓群落特征能够很好地反映洞内Hg污染的变化趋势。RDA排序结果分析表明:洞穴苔藓群落为适应低光度环境会表现出向光性运动、喜钙生基质、耐重金属等生理特征。蛇苔(Conocephalumconicum)植物体内的Hg含量与其基质Hg含量具有显著相关性(P<0.05),说明蛇苔受基质Hg污染影响较大。在今后的治理过程中,可以考虑将蛇苔作为洞内环境的生物监测材料之一。

Boosting image-guiding radiation therapy through W_(18)O_(49) nanospheres and the second near-infrared light irradiation

More than 60%of cancer patients receive radiation therapy(RT)during their anticancer treatment.However,there is a huge challenge to improve the therapeutic efficacy of RT in less radioresponsive tumors and decrease damages dealt to the surrounding healthy tissues.Herein,we have reported the development of an efficacious RT treatment of relatively radio-resistant breast cancer using W_(18)O_(49)nanospheres and the second near-infrared(NIR)light irradiation.Featuring the X-ray attenuation ability and photothermal effect,together with ability to generate intracellular singlet oxygen and·OH,W_(18)O_(49)nanospheres can significantly increase radiation-induced DNA damage and decrease the mitochondrial membrane potential of cancer cells during RT,causing in nearby three-times improvement in inhibiting the proliferation of 4T1 cells.The in vivo evaluations verify that a rather effective therapeutic outcome is achieved by treatment of 4T1 tumor xenograft with NIR-enhanced RT using W_(18)O_(49)nanospheres.Moreover,the X-ray attenuation ability and the strong near-infrared absorption of W_(18)O_(49)nanospheres have enabled highly resolved in vivo computer tomography(CT)/photoacoustic(PA)imaging.This work presents an“all-in-one”synergistic platform to improve the therapeutic efficacy of RT in less radioresponsive tumors,therefore opening a new door for multimodal cancer therapy.

A verifiable privacy-preserving data collection scheme supporting multi-party computation in fog-based smart grid

Incorporation of fog computing with low latency,preprocession(e.g.,data aggregation)and location awareness,can facilitate fine-grained collection of smart metering data in smart grid and promotes the sustainability and efficiency of the grid.Recently,much attention has been paid to the research on smart grid,especially in protecting privacy and data aggregation.However,most previous works do not focus on privacy-preserving data aggregation and function computation query on enormous data simultaneously in smart grid based on fog computation.In this paper,we construct a novel verifiable privacy-preserving data collection scheme supporting multi-party computation(MPC),named VPDC-MPC,to achieve both functions simultaneously in smart grid based on fog computing.VPDC-MPC realizes verifiable secret sharing of users’data and data aggregation without revealing individual reports via practical cryptosystem and verifiable secret sharing scheme.Besides,we propose an efficient algorithm for batch verification of share consistency and detection of error reports if the external adversaries modify the SMs’report.Furthermore,VPDC-MPC allows both the control center and users with limited resources to obtain arbitrary arithmetic analysis(not only data aggregation)via secure multi-party computation between cloud servers in smart grid.Besides,VPDC-MPC tolerates fault of cloud servers and resists collusion.We also present security analysis and performance evaluation of our scheme,which indicates that even with tradeoff on computation and communication overhead,VPDC-MPC is practical with above features.