Improved Data Confidentiality of Audit Trail Data in Multi-Tenant Cloud

Cloud computing is delivery of services rather than a product and among different cloud deployment models, the public cloud provides improved scalability and cost reduction when compared to others. Security and privacy of data is one of the key factors in transitioning to cloud. Typically the cloud providers have a demilitarized zone protecting the data center along with a reverse proxy setup. The reverse proxy gateway acts as initial access point and provides additional capabilities like load balancing, caching, security monitoring capturing events, syslogs related to hosts residing in the cloud. The audit-trail logs captured by reverse proxy server comprise important information related to all the tenants. While the PKI infrastructure works in cloud scenario it becomes cumbersome from manageability point of view and they lack flexibility in providing controlled access to data. In this paper we evaluate risks associated with security and privacy of audit logs produced by reverse proxy server. We provide a two-phase approach for sharing the audit-logs with users allowing fine-grained access. In this paper we evaluate certain Identity-Based and AttributeBased Encryption schemes and provide detailed analysis on performance

Experiments in Encrypted and Searchable Network Audit Logs

We consider the scenario where a consumer can securely outsource their network telemetry data to a Cloud Service Provider and enable a third party to audit such telemetry for any security forensics. Especially we consider the use case of privacy preserving search in network log audits. In this paper we experiment with advances in Identity Based Encryption and Attribute-Based encryption schemes for auditing network logs

Comparative SNP and Haplotype Analysis Reveals a Higher Genetic Diversity and Rapider LD Decay in Tropical than Temperate Germplasm in Maize

Understanding of genetic diversity and linkage disequilibrium (LD) decay in diverse maize germplasm is fundamentally important for maize improvement. A total of 287 tropical and 160 temperate inbred lines were genotyped with 1943 single nucleotide polymorphism (SNP) markers of high quality and compared for genetic diversity and LD decay using the SNPs and their haplotypes developed from genic and intergenic regions. Intronic SNPs revealed a substantial higher variation than exonic SNPs. The big window size haplotypes (3-SNP slide-window covering 2160 kb on average) revealed much higher genetic diversity than the 10 kb-window and gene-window haplotypes. The polymorphic information content values revealed by the haplotypes (0.436–0.566) were generally much higher than individual SNPs (0.247–0.259). Cluster analysis classified the 447 maize lines into two major groups, corresponding to temperate and tropical types. The level of genetic diversity and subpopulation structure were associated with the germplasm origin and post-domestication selection. Compared to temperate lines, the tropical lines had a much higher level of genetic diversity with no significant subpopulation structure identified. Significant variation in LD decay distance (2–100 kb) was found across the genome, chromosomal regions and germplasm groups. The average of LD decay distance (10–100 kb) in the temperate germplasm was two to ten times larger than that in the tropical germplasm (5–10 kb). In conclusion, tropical maize not only host high genetic diversity that can be exploited for future plant breeding, but also show rapid LD decay that provides more opportunity for selection

Development and use of genic molecular markers (GMMs) for construction of a transcript map of chickpea (Cicer arietinum L.)

A transcript map has been constructed by the development and integration of genic molecular markers (GMMs) including single nucleotide polymorphism (SNP), genic microsatellite or simple sequence repeat (SSR) and intron spanning region (ISR)-based markers, on an inter-specific mapping population of chickpea, the third food legume crop of the world and the first food legume crop of India. For SNP discovery through allele re-sequencing, primer pairs were designed for 688 genes/expressed sequence tags (ESTs) of chickpea and 657 genes/ESTs of closely related species of chickpea. High-quality sequence data obtained for 220 candidate genic regions on 2–20 genotypes representing 9 Cicer species provided 1,893 SNPs with an average frequency of 1/35.83 bp and 0.34 PIC (polymorphism information content) value. On an average 2.9 haplotypes were present in 220 candidate genic regions with an average haplotype diversity of 0.6326. SNP2CAPS analysis of 220 sequence alignments, as mentioned above, provided a total of 192 CAPS candidates. Experimental analysis of these 192 CAPS candidates together with 87 CAPS candidates identified earlier through in silico mining of ESTs provided scorable amplification in 173 (62.01%) cases of which predicted assays were validated in 143 (82.66%) cases (CGMM). Alignments of chickpea unigenes with Medicago truncatula genome were used to develop 121 intron spanning region (CISR) markers of which 87 yielded scorable products. In addition, optimization of 77 EST-derived SSR (ICCeM) markers provided 51 scorable markers. Screening of easily assayable 281 markers including 143 CGMMs, 87 CISRs and 51 ICCeMs on 5 parental genotypes of three mapping populations identified 104 polymorphic markers including 90 markers on the inter-specific mapping population. Sixty-two of these GMMs together with 218 earlier published markers (including 64 GMM loci) and 20 other unpublished markers could be integrated into this genetic map. A genetic map developed here, therefore, has a total of 300 loci including 126 GMM loci and spans 766.56 cM, with an average inter-marker distance of 2.55 cM. In summary, this is the first report on the development of large-scale genic markers including development of easily assayable markers and a transcript map of chickpea. These resources should be useful not only for genome analysis and genetics and breeding applications of chickpea, but also for comparative legume genomics

A method for the automatic segmentation of brown adipose tissue

Objective: Brown adipose tissue (BAT) plays a key role for thermogenesis in mammals and infants. Recent confirmation of BAT presence in adult humans has aroused great interest for its potential to initiate weight-loss and normalize metabolic disorders in diabetes and obesity. Reliable detection and differentiation of BAT from the surrounding white adipose tissue (WAT) and muscle is critical for assessment/quantification of BAT volume. This study evaluates magnetic resonance (MR) acquisition for BAT and the efficacy of different automated methods for MR features-based BAT segmentation to identify the best suitable method. Materials and methods: Multi-point Dixon and multi-echo T spin-echo images were acquired from 12 mice using an Agilent 9.4T scanner. Four segmentation methods: multidimensional thresholding (MTh); region-growing (RG); fuzzy c-means (FCM) and neural-network (NNet) were evaluated for the interscapular region and validated against manually defined BAT, WAT and muscle. Results: Statistical analysis of BAT segmentation yielded a median Dice-Statistical-Index, and sensitivity of 89. 92\ua0% for NNet, 82. 86\ua0% for FCM, 72. 74\ua0% for RG, and 72. 70\ua0%, for MTh, respectively. Conclusion: This study demonstrates that NNet improves the specificity to BAT from surrounding tissue based on 3-point Dixon and T MRI. This method facilitates quantification and longitudinal measurement of BAT in preclinical-models and human subjects

Fast Adipogenesis Tracking System (FATS)—a robust, high-throughput, automation-ready adipogenesis quantification technique

Abstract Adipogenesis is essential in in vitro experimentation to assess differentiation capability of stem cells, and therefore, its accurate measurement is important. Quantitative analysis of adipogenic levels, however, is challenging and often susceptible to errors due to non-specific reading or manual estimation by observers. To this end, we developed a novel adipocyte quantification algorithm, named Fast Adipogenesis Tracking System (FATS), based on computer vision libraries. The FATS algorithm is versatile and capable of accurately detecting and quantifying percentage of cells undergoing adipogenic and browning differentiation even under difficult conditions such as the presence of large cell clumps or high cell densities. The algorithm was tested on various cell lines including 3T3-L1 cells, adipose-derived mesenchymal stem cells (ASCs), and induced pluripotent stem cell (iPSC)-derived cells. The FATS algorithm is particularly useful for adipogenic measurement of embryoid bodies derived from pluripotent stem cells and was capable of accurately distinguishing adipogenic cells from false-positive stains. We then demonstrate the effectiveness of the FATS algorithm for screening of nuclear receptor ligands that affect adipogenesis in the high-throughput manner. Together, the FATS offer a universal and automated image-based method to quantify adipocyte differentiation of different cell lines in both standard and high-throughput workflows

Influence of microstructure and mechanical properties on the tribological behavior of reactive arc deposited Zr-Si-N coatings at room and high temperature

Varying the Si-content in Zr-Si-N coatings from 0.2 to 6.3 at.% causes microstructural changes from columnar to nanocomposite structure and a hardness drop from 37 to 26 GPa. The softer nanocomposite also displays lower fracture resistance. The tribological response of these coatings is investigated under different contact conditions, both at room and elevated temperatures. At room temperature tribooxidation is found to be the dominant wear mechanism, where the nanocomposite coatings display the lowest wear rate of 0.64 × 10- 5 mm3/Nm, by forming an oxide diffusion barrier layer consisting of Zr, W, and Si. A transition in the dominant wear mechanism from tribooxidation to microploughing is observed upon increasing the test temperature and contact stress. Here, all coatings exhibit significantly higher coefficient of friction of 1.4 and the hardest coatings with columnar structure display the lowest wear rate of 10.5 × 10- 5 mm3/Nm. In a microscopic wear test under the influence of contact-induced dominant elastic stress field, the coatings display wedge formation and pileup due to accumulation of the dislocation-induced plastic deformation. In these tests, the nanocomposite coatings display the lowest wear rate of 0.56 × 10- 10 mm3/Nm, by constraining the dislocation motionPeer Reviewe