Survey on differential privacy and its progress

With the arrival of the era of big data sharing,data privacy protection issues will be highlighted.Since its introduction in 2006,differential privacy technology has been widely researched in data mining and data publishing.In recent years,Google,Apple and other companies have introduced differential privacy technology into the latest products,and differential privacy technology has become the focus of academia and industry again.Firstly,the traditional centralized model of differential privacy was summarized,from the perspective of analysis of data mining and data released in the differential privacy way.Then the latest local differential privacy regarding data collection and data analysis based on the local model was described,involving crowdsourcing with random response technology,BloomFilter,statistical inference techniques.Finally,the main problems and solutions of differential privacy technology were summarized.     

Bacterial communication systems: A mathematical formulation of negative chemotaxis

The emergence of molecular communication (MC) has provided a new paradigm for communication at nanoscale, besides the electromagnetic one. Numerous biological systems have been proposed that could be used for communication, using mostly bacteria as information carriers, ensuring biocompatibility and low complexity requirements. In this work, message dissemination dynamics in a bacterial communication system was under investigation by means of a simulation framework that was designed and developed based on a commercial tool. A mathematical formulation is proposed, in an effort to accurately predict the system's behavior under the presence of chemotactic‐like nodes. Simulation results are in strong agreement with the respective mathematical model, for a wide range of biological processes, including phenomena such as chemotaxis, bacterial growth cycle, and biological message transformation dynamics. In the case of a simple simulation scenario exhibiting chemotaxis, the mean accuracy improvement reaches values of up to 19% .     

Single-Round DNA Aptamer Selection by Combined Use of Capillary Electrophoresis and Next Generation Sequencing: An Aptaomics Approach for Identifying Unique Functional Protein-Binding DNA Aptamers

In DNA aptamer selection, existing methods do not discriminate aptamer sequences based on their binding affinity and function and the reproducibility of the selection is often poor, even for the selection of well-known aptamers like those that bind the commonly used model protein thrombin. In the present study, a novel single-round selection method (SR-CE selection) was developed by combining capillary electrophoresis (CE) with next generation sequencing. Using SR-CE selection, a successful semi-quantitative and semi-comprehensive aptamer selection for thrombin was demonstrated with high reproducibility for the first time. Selection rules based on dissociation equilibria and kinetics were devised to obtain families of analogous sequences. Selected sequences of the same family were shown to bind thrombin with high affinity. Furthermore, data acquired from SR-CE selection was mined by creating sub-libraries that were categorized by the functionality of the aptamers (e. g., pre-organized aptamers versus structure-induced aptamers). Using this approach, a novel fluorescent molecular recognition sensor for thrombin with nanomolar detection limits was discovered. Thus, in this proof-of-concept report, we have demonstrated the potential of a “DNA Aptaomics” approach to systematically design functional aptamers as well as to obtain high affinity aptamers.     

Red/Near‐Infrared Emissive Metalloporphyrin‐Based Nanodots for Magnetic Resonance Imaging‐Guided Photodynamic Therapy In Vivo

Near‐infrared emissive (NIR) porphyrin‐implanted carbon nanodots (PCNDs or MPCNDs) are prepared by selectively carbonization of free base or metal complexes [M = Zn(II) or Mn(III)] of tetra‐(meso‐aminophenyl)porphyrin in the presence of citric acid. The as‐prepared nanodots exhibit spontaneously NIR emission, small size, good aqueous dispersibility, and favorable biocompatibility characteristic of both porphyrins and pristine carbon nanodots. The subcellular localization experiment of nanodots indicates a lysosome‐targeting feature. And the in vitro photodynamic therapy (PDT) results on HeLa cells indicate the nanodots alone have no adverse effect on tumor cells, but display remarkable photodynamic efficacy upon irradiation. Moreover, MnPCNDs containing paramagnetic Mn(III) ions, which possesses good biocompatibility, NIR luminescence, and magnetic resonance imaging and efficient singlet oxygen production, are further studied in magnetic resonance imaging‐guided photodynamic therapy in vivo.     

大数据时代下数字生活社区的前景

随着信息化大数据时代的到来,既给信息科技从业者带来新的机遇和挑战的同时,也给大众百姓的生活带来巨大的品质提升,数字生活社区将引导一场前所未有的技术革命,对影响人们衣、食、住、行、医等方方面面,也使得人们对科技生活的依赖性更加增强,更加的理所当然.     

数据挖掘在人力资源信息分析中的应用

企业的竞争归根结底是人才的竞争，如何全面掌握和合理利用人才资源是公司人力资源管理的首要问题。本文首先简单介绍了数据挖掘技术的背景、常用技术及运作流程，在此基础上阐述了数据挖掘技术在人力资源信息系统中的应用。     

Metal‐ and solvent‐free,clickable synthesis and postpolymerization functionalization of poly(triazole)s

In this study, a series of linear poly(triazole)s (PTAs) were successfully synthesized by the metal‐ and solvent‐free, thermal click polymerization of diazide and dialkyne (A₂ + B₂) monomers. All click polymerizations proceeded smoothly at 80 °C in an open atmosphere without protection from oxygen and moisture. After being polymerized for 36 h, the crude polymer was further fractionated into three fractions using a multistep precipitation method. By selectively choosing precipitating agents, this process produced poly(triazole) fractions with low polydispersity index (<1.30). The resulting PTAs are soluble in common organic solvents and stable at a temperature up to 320 °C. Furthermore, the methyl benzoate moieties in the main chain can serve as useful building blocks for further postpolymerization functionalization, yielding 1,2,4‐triazole derivatives. This functionalization strategy offers potential for the development of novel triazole‐based materials. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Synthesis of novel side‐chain triphenylamine polymers with azobenzene moieties via RAFT polymerization and investigation on their photoelectric properties

Two novel and well‐defined polymers, poly[6‐(5‐(diphenylamino)‐2‐((4‐methoxyphenyl)diazenyl)phenoxy)hexyl methacrylate] (PDMMA) and poly[6‐(4‐((3‐ethynylphenyl)diazenyl) phenoxy)hexyl methacrylate] (PDPMMA), which bear triphenylamine (TPA) incorporated to azobenzene either directly (PDMMA) or with an interval (PDPMMA) as pendant groups were successfully prepared via reversible addition‐fragmentation chain transfer polymerization technique. The electrochemical behaviors of PDPMMA and PDMMA were investigated by cyclic voltammograms (CV) measurement. The hole mobilities of the polymer films were determined by fitting the J‐V (current‐voltage) curve into the space‐charge‐limited current method. The influence of photoisomerization of the azobenzene moiety on the behaviors of fluorescence emission, CV and hole mobilities of these two polymers were studied. The fluorescent emission intensities of these two polymers in CH₂Cl₂ were increased by about 100 times after UV irradiation. The oxidation peak currents (I_OX) of the PDMMA and PDPMMA in CH₂Cl₂ were increased after UV irradiation. The photoisomerization of the azobenzene moiety in PDMMA had significant effect on the electrochemical behavior, compared with that in PDPMMA. The changes of the hole mobility before and after UV irradiation were very small for both polymers. The HOMO energies (E_HOMO, HOMO: the highest occupied molecular orbital) of side chain moieties of TPA incorporated with cis‐isomer and trans‐isomer of azobenzene in PDMMA and PDPMMA were obtained by theoretical calculation, which are basically consistent with the experimental results. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Synthesis and properties of hyperbranched poly(ether sulfone)s prepared by self‐polycondensation of novel AB2 monomer

Hyperbranched poly(ether sulfone)s were prepared by the self‐polycondensation of the novel AB₂ monomer, 4‐(3,5‐hydroxyphenoxy)‐4′‐fluorodiphenylsulfone. The high‐molecular‐weight polymers were isolated in good yields. The degree of branching (DB) of the resulting polymers was investigated by the preparation of dendritic and linear model compounds. The DB determined by gated decoupling ¹³C NMR measurements was in the range 0.17–0.41 and was dependent on the base used for the self‐polycondensation. It was found that cesium fluoride was an effective base to form the polymer having the DB of 0.41. The resulting hyperbranched poly(ether sulfone)s showed good solubility in organic solvents. The solubility and the glass transition temperature of the polymers were influenced by the terminal functional groups. The unique thermal crosslinking phenomenon was observed during the DSC measurements of the hydroxyl‐terminated hyperbranched poly(ether sulfone) under air condition. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Deprotection‐free preparation of propargyl ether‐containing phosphinated benzoxazine and the structure–property relationship of the resulting thermosets

Generally, protection and deprotection procedures of amino groups are required in preparing propargyl ether‐containing benzoxazines. In this study, we report a facile, deprotection‐free preparation of a propargyl ether‐containing phosphinated benzoxazine (2) from the nucleophilic substitution of a phenolic OH‐containing phosphinated benzoxazine (1) and propargyl bromide in the catalysis of potassium carbonate. The structure of (2) was characterized and confirmed by a high‐resolution mass spectrum, ¹H, ¹³C, ¹H‐¹H, ¹H‐¹³C nuclear magnetic resonance (NMR) spectra, and X‐ray single crystal diffractogram. infrared (IR) and differential scanning calorimetry were used to monitor the ring‐opening of benzoxazine and crosslinking of propargyl ether. The microstructure and the structure–property relationship of the resulting homopolymers and copolymers are discussed. The T_g of homopolymer of (2) is 208 °C by dynamic mechanical analysis, the coefficient of thermal expansion is 43 ppm/°C, and T_d 5% (N₂) is 393 °C, respectively, which are higher than those of the homopolymer of (1) . Similar trends were observed in the copolymerization system. The results demonstrate the beneficial effect of crosslinking afforded by the propargyl ether group is higher than that by the phenolic OH group. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012