Indexing Information for Data Forensics

We introduce novel techniques for organizing the indexing structures of how data is stored so that alterations from an original version can be detected and the changed values specifically identified. We give forensic constructions for several fundamental data structures, including arrays, linked lists, binary search trees, skip lists, and hash tables. Some of our constructions are based on a new reduced-randomness construction for nonadaptive combinatorial group testing

Avaliação histológica da próstata de cães adultos sexualmente intactos

Avaliou-se histologicamente a próstata de 30 cães adultos e idosos sexualmente intactos que apresentavam ou não sintomatologia clínica de doença prostática, e verificou-se a incidência de possíveis alterações da glândula. Dentre as alterações encontradas, a hiperplasia prostática benigna constituiu o diagnóstico mais comum, 85,6% (n=24), seguida por prostatite crônica, 64,3% (n=18), displasia do epitélio glandular, 42,8% (n=12), atrofia do epitélio glandular, 39,3% (n=11), infiltrado inflamatório focal, 25% (n=7), dilatação glandular focal, 21,4% (n=6), prostatite aguda, 7,1% (n=2), metaplasia escamosa, 3,6%, (n=1), metástase de neoplasia sistêmica, 3,6% (n=1) e abscesso prostático, 3,6% (n=1). Como em muitos casos os cães são assintomáticos, ressalta-se a importância da realização rotineira de exames clínicos específicos, como o toque retal e a ultrassonografia, para o diagnóstico precoce e o tratamento das afecções prostáticas.The prostates of 30 not castrated old dogs with or without clinical symptoms of prostatic disease were histologically evaluated. It was observed the incidence of possible changes in the gland. Among the changes, benign prostatic hyperplasia (BPH) was the most common diagnosis, accounting for 85.6% (n=24), followed by chronic prostatitis, 64.3% (n=18), dysplasia of the glandular epithelium, 42.8% (n=12), atrophy of the glandular epithelium, 39.3% (n=11), focal inflammatory infiltrate, 25% (n=7), focal glandular dilation, 21.4% (n=6), acute prostatitis, 7.1% (n=2), squamous metaplasia, 3.6% (n=1), metastasis of systemic neoplasia, 3.6% (n=1), and prostatic abscess, 3.6% (n=1). Because the lack of symptoms in most of dogs with prostatic changes, the specific clinic exams in routine, as rectal palpation and ultrasonography, are very important to early diagnosis and treatment of dogs with prostatic disease

Hydrodynamics of DNA confined in nanoslits and nanochannels

Modeling the dynamics of a confined, semiflexible polymer is a challenging problem, owing to the complicated interplay between the configurations of the chain, which are strongly affected by the length scale for the confinement relative to the persistence length of the chain, and the polymer-wall hydrodynamic interactions. At the same time, understanding these dynamics are crucial to the advancement of emerging genomic technologies that use confinement to stretch out DNA and “read” a genomic signature. In this mini-review, we begin by considering what is known experimentally and theoretically about the friction of a wormlike chain such as DNA confined in a slit or a channel. We then discuss how to estimate the friction coefficient of such a chain, either with dynamic simulations or via Monte Carlo sampling and the Kirkwood pre-averaging approximation. We then review our recent work on computing the diffusivity of DNA in nanoslits and nanochannels, and conclude with some promising avenues for future work and caveats about our approach

Hydrogen reduction of a Cu2O-WO3 mixture

In the present work, the reduction kinetics of Cu2O-WO3 mixtures by hydrogen gas was studied by thermogravimetric analyses (TGA). The reduction experiments were carried out both isothermally and nonisothermally on shallow powder beds in the temperature interval 673 to 1073 K. During the experiments, the reductant gas flow rate was kept just above the starvation rate for the reaction to ensure that chemical reaction was the rate-controlling step. The composition and microstructures of the reaction products were analyzed after each experiment by X-ray diffraction (XRD) as well as by microprobe analyses. In the temperature interval 673 to 923 K, copper oxide was found to be preferentially reduced in the early stages of the experiment followed by the reduction of tungsten oxide. The reaction mechanism was found to be affected by a reaction/transformation in the starting copper-tungsten oxide mixtures in the temperature interval 923 to 973 K. At temperatures higher than 973 K, the reduction of the complex oxide formed was found to have a strong impact on the reaction kinetics. The activation energy was evaluated, from the isothermal as well as nonisothermal reduction experiments, for the two stages of reduction identified. The XRD and scanning electron microscopy (SEM) studies indicated the formation of a metastable solution of copper in tungsten at about 923 K. The advantage of the hydrogen reduction route toward the bulk production of alloy powders in the nanosize is demonstrated.</p

Non-Adaptive Complex Group Testing with Multiple Positive Sets

Given n items with at most d of them having a particular property (referred as positive items), a test on a selected subset of them is positive if and only if the subset contains at least one positive item. The non-adaptive group testing problem is to design how to group the items to minimize the number of tests required to identify all positive items in which all tests are performed in parallel. This problem is well-studied and algorithms exist that match the lower bound with a small gap of log d asymptoticically. An important generalization of the problem is to consider the case that individual positive item cannot make a test positive, but a combination of them (referred as positive subsets) can do. The problem is referred as the non-adaptive complex group testing. Assume there are at most d positive subsets whose sizes are at most s, existing algorithms either require Ω(log s n) tests for general n or O ( () s+d log n) tests for some special values of n. However, the number d of items in each test cannot be very small or very large in real situation. The above algorithms cannot be applied because there is no control on the number of items in each test. In this paper, we provide a novel and practical derandomized algorithm to construct the tests with two important properties. (1) Our algorithm requires only O ( (d + s) d+s+1 /(ddss) log n) tests for all positive integers n which matches the upper bound on the number of tests when all positive subsets are singletons, i.e. s = 1. (2) All tests in our algorithm can have the same number of tested items k. Thus, our algorithm can solve the problem with additional constraints on the number of tested items in each test, such as maximum or minimum number of tested items