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This paper considers the problem of publishing "transaction data" for research purposes. Each transaction is an arbitrary set of items chosen from a large universe. Detailed transaction data provides an electronic image of one's life. This has two implications. One, transaction data are excellent candidates for data mining research. Two, use of transaction data would raise serious concerns over individual privacy. Therefore, before transaction data is released for data mining, it must be made anonymous so that data subjects cannot be re-identified. The challenge is that transaction data has no structure and can be extremely high dimensional. Traditional anonymization methods lose too much information on such data. To date, there has been no satisfactory privacy notion and solution proposed for anonymizing transaction data. This paper proposes one way to address this issue.

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The boundary paradigm (K. Rayner, 1975) was used to determine the extent to which Chinese readers obtain information from the right of fixation during reading. As characters are the basic visual unit in written Chinese, they were used as targets in Experiment 1 to examine whether readers obtain preview information from character n + 1 and character n + 2. The results from Experiment 1 suggest they do. In Experiment 2, 2-character target words were used to determine whether readers obtain preview information from word n + 2 as well as word n + 1. Robust preview effects were obtained for word n + 1. There was also evidence from gaze duration (but not first fixation duration), suggesting preview effects for word n + 2. Moreover, there was evidence for parafoveal-on-foveal effects in Chinese reading in both experiments. Implications of these results for models of eye movement control are discussed.

After nearly a decade of anticipation, scalable nonvolatile memory DIMMs are finally commercially available with the release of the Intel® Optane™ DC Persistent Memory Module (or just "Optane DC PMM"). This new nonvolatile DIMM supports byte-granularity accesses with access times on the order of DRAM, while also providing data storage that survives power outages.This work comprises the first in-depth, scholarly, performance review of Intel's Optane DC PMM, exploring its capabilities as a main memory device, and as persistent, byte-addressable memory exposed to user-space applications. For the past several months, our group has had access to machines with Optane DC memory and has investigated the Optane DC PMM's performance characteristics. This report details the chip's performance under a number of modes and scenarios, and across a wide variety of both micro-and macro-scale benchmarks. In total, this report represents approximately 330 hours of machine time.Optane DC memory occupies a tier in-between SSDs and DRAM. It has higher latency (346 ns) than DRAM but lower latency than an SSD. Unlike DRAM, its bandwidth is asymmetric with respect to access type: for a single Optane DC PMM, its max read bandwidth is 6.6 GB/s, whereas its max write bandwidth is 2.3 GB/s. However, the expected price point of Optane DC memory means that machines with large quantities of Optane DC memory are feasible -our test machine has 3 TB of Optane DC memory across two sockets.Optane DC PMMs can be used as large memory devices with a DRAM cache to hide their lower bandwidth and higher latency. When used in this Memory (or cached) mode, Optane DC memory has little impact on applications with small memory footprints. Applications with larger memory footprints may experience some slow-down relative to DRAM, but are now able to keep much more data in memory.In contrast, in App Direct (or uncached) mode, Optane DC PMMs can be used as a persistent storage device. When used under a file system, this configuration can result in significant performance gains, especially when the file system is optimized to use the load/store interface of the Optane DC PMM and the application uses many small, persistent writes. For instance, using the NOVA-relaxed NVMM file system, we can improve the performance of Kyoto Cabinet by almost 2×.In App Direct mode, Optane DC PMMs can also be used to enable user-space persistence where the application explicitly controls its writes into persistent Optane DC media. By modifying the actual application, application programmers can gain additional performance benefits since persistent updates bypass both the kernel and file system. In our experiments, modified applications that used user-space Optane DC persistence generally outperformed their file system counterparts; for instance, the user-space persistent version of RocksDB performed almost 2× faster than the equivalent program utilizing an NVMM-aware file system. This early report is only the beginning in an effort to understand these new memory devices. We hope that ...

Personalized web search is a promising way to improve search quality by customizing search results for people with individual information goals. However, users are uncomfortable with exposing private preference information to search engines. On the other hand, privacy is not absolute, and often can be compromised if there is a gain in service or profitability to the user. Thus, a balance must be struck between search quality and privacy protection. This paper presents a scalable way for users to automatically build rich user profiles. These profiles summarize a user's interests into a hierarchical organization according to specific interests. Two parameters for specifying privacy requirements are proposed to help the user to choose the content and degree of detail of the profile information that is exposed to the search engine. Experiments showed that the user profile improved search quality when compared to standard MSN rankings. More importantly, results verified our hypothesis that a significant improvement on search quality can be achieved by only sharing some higher-level user profile information, which is potentially less sensitive than detailed personal information.

In this work, silica nanoparticles covered with an initiator silane were grafted with novel biocompatible and functionalizable zwitterionic poly[[3-(acryloylamino)propyl](2-carboxyethyl)dimethylammonium] (polyCBAA) via atomic transfer radical polymerization. The stability of these particles in protein solutions and their functionalization were investigated. Dynamic light scattering and transmission electron microscopy were employed to characterize these particles. Results indicate that the polyCBAA-modified nanoparticles are stable for at least 72 h in both negative and positive protein solutions. The size distribution remains the same before and after protein incubation. Moreover, our results show that polyCBAA-modified silica nanoparticles can be easily functionalized. This makes these particles ideal candidates for future applications in targeted drug delivery and diagnostics in complex media.

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