Optimal Active Social Network De-anonymization Using Information Thresholds

In this paper, de-anonymizing internet users by actively querying their group memberships in social networks is considered. In this problem, an anonymous victim visits the attacker's website, and the attacker uses the victim's browser history to query her social media activity for the purpose of de-anonymization using the minimum number of queries. A stochastic model of the problem is considered where the attacker has partial prior knowledge of the group membership graph and receives noisy responses to its real-time queries. The victim's identity is assumed to be chosen randomly based on a given distribution which models the users' risk of visiting the malicious website. A de-anonymization algorithm is proposed which operates based on information thresholds and its performance both in the finite and asymptotically large social network regimes is analyzed. Furthermore, a converse result is provided which proves the optimality of the proposed attack strategy

Seeded Graph Matching: Efficient Algorithms and Theoretical Guarantees

In this paper, a new information theoretic framework for graph matching is introduced. Using this framework, the graph isomorphism and seeded graph matching problems are studied. The maximum degree algorithm for graph isomorphism is analyzed and sufficient conditions for successful matching are rederived using type analysis. Furthermore, a new seeded matching algorithm with polynomial time complexity is introduced. The algorithm uses `typicality matching' and techniques from point-to-point communications for reliable matching. Assuming an Erdos-Renyi model on the correlated graph pair, it is shown that successful matching is guaranteed when the number of seeds grows logarithmically with the number of vertices in the graphs. The logarithmic coefficient is shown to be inversely proportional to the mutual information between the edge variables in the two graphs

The Effect of Cutting Efficacy of Diamond Burs on Microleakage of Class V Resin Composite Restorations Using Total Etch and Self Etch Adhesive Systems

Objective: In this study, the effect of bur cutting efficacy was evaluated on microleakage of class V composite restorations with two adhesive systems.Materials and Methods: Class V cavities were produced on sound extracted human teeth,which had been assigned randomly to one of six groups (N=15) as follows: Groups 1 and 6 were prepared using used rough diamond bur; Group 2 and 5 were prepared using new rough diamond bur; Group 3 and 4 were prepared using soft diamond bur. After application of Single Bond (3M Dental Product, USA) in groups 4,5 and 6 and Clearfil SE Bond [Kurary Medical Inc. Japan] in groups 1,2 and 3, all cavities were restored with composite resin. The teeth were thermocycled and microleakage was evaluated by dye penetration.Kruskal-Wallis and Mann-Whitney tests with Bonferroni's correction were used for statistical analysis.Results: The results showed that gingival margins significantly leaked more than occlusal margins for all bur types and bonding systems. Using the same adhesive system in gingival margins, significant difference was seen between bur types and using the same bur type in occlusal margins, there was a significant difference between the two types of adhesive systems.Conclusion: Cutting efficiency of bur had a great effect on microleakage of resin composite restorations. So long term use of burs may result in an increase in microleakage of composite resin restorations

Morphological abnormality among regenerated shoots of banana and plantain (Musa spp.) after in vitro multiplication with TDZ and BAP from excised shoottips

Five cultivars of Musa spp (banana and plantain); ‘Berangan Intan’, ‘Berangan’ (AAA), ‘Rastali’, ‘Nangka’ (AAB) and ‘Baka Baling’ (ABB) were chosen to compare the effect of benzylaminopurine (BAP) and thidiazuron (TDZ) on multiplication efficiency in relation with frequency of abnormal shoot regeneration. Shoot tips of Musa spp. were cultured on MS medium supplemented with various concentrations (0.0, 11.1, 22.2, 33.3 and 44.4 ìM) of BAP and (0.0, 0.5, 2, 5 and 7.5 ìM) of TDZ. Increasing BAP above 22.2 ìM and 33.3 ìM increased the number of shoots in ‘Berangan Intan’,‘Berangan’, ‘Rastali’, ‘Nangka’ and ‘Baka Baling’ respectively, but above 33.3 ìM significantly caused higher gross of abnormal shoot regeneration. TDZ in the media up to 2 ìM for ‘Baka Baling’, ‘Nangka’ and ‘Rastali’ and 5 ìM for ‘Berangan Intan’ and ‘Berangan’ increased the number of shoots per explant,however TDZ at 5 ìM resulted in high number of abnormal shoots. In conclusion BAP at 22.2 ìM and TDZ at 2 ìM were assumed to be the most suitable for commercial micropropagation system with low frequency of abnormal shoot production for both banana and plantain

The prevalence of metabolic syndrome in psoriatic arthritis patients, a hospital-based cross-sectional study on Iranian population

Background: Psoriasis is a T-cell mediated chronic inflammatory disorder with multiple skin, nails and joints involvement. The reported prevalence of psoriatic arthritis varies from 5 to 42 cases per 100 psoriasis patients. Insulin resistance is believed to be central to the pathogenesis of metabolic syndrome, a constellation of major risk factors for cardiovascular diseases, including atherogenic dyslipidemia, truncal adiposity, hypertension and hyperglycemia. The association of psoriasis and psoriatic arthritis with metabolic syndrome is increasingly being reported. Although the literature relating psoriatic arthritis to metabolic syndrome is accumulating, there is still a paucity of evidence, especially from Asia. Here, we examined the prevalence of metabolic syndrome and its components in patients with psoriatic arthritis. Methods: The study was performed among outpatients attending the specialty clinic and rheumatology ward of Rasoul-e-Akram general hospital between January 2014 and April 2015. A consecutive sample of 80 patients diagnosed as having psoriatic arthritis was studied. Age, gender, body mass index, blood pressure and waist circumference, and history of smoking of patients were measured and asked at the enrolment visit. Venous samples were taken after 8 h of overnight fasting for the estimation of serum lipid profile, glucose and uric acid levels. Also an ultrasonographic examination was done for detection of non-alcoholic fatty liver disease. Results: 46 patients (57.5) were male and 34 patients (42.5) were female. Mean age of the participants was 43 years (SD: 11.3). The prevalence of abnormal components of metabolic syndrome was 53.8 for BMI, 48.8 for TG level, 50 for HDL, 46.3 for LDL, 45 for Cholesterol, 23.8 for FBS, 46 for waist circumflex in men and 47.7 in women and 42.5 for uric acid. 40 of the patients had abnormal SBP and 41.2 had abnormal DBP. Thirty percent of the participants were current smokers and 43.8 had NAFLD on ultrasonographic examination. Conclusion: 51.3 of patients had metabolic syndrome according to the adult treatment panel III criteria for adult Asian patients. � 2016, Tehran University of Medical Sciences. All rights reserved

Evaluation and comparison of dosimetric parameters in PTV for prostate cancer via step and shoot IMRT and 3DCRT

The aim of radiation therapy treatment planning is to achieve an optimal balance between delivering a high dose to target volume and a low dose to healthy tissues. The integral dose, conformity and homogeneity indexes, hence, are the important guidance for predicting the radiation effects and choosing the optimal treatment plan. The goal of this study is to compare and investigate the aforementioned parameters in 3DCRT vs. IMRT plan. In order to evaluate dosimetric parameters, data from five patients with prostate cancer, planned by IMRT and 3DCRT were obtained. Prescribed doses for IMRT procedure and 3DCRT were 80Gy and 70 Gy, respectively. Also, the target coverage was achieved with 95% of the prescribed dose to 95% of the PTV in 3DCRT and 95% of the prescribed dose to 98% of the PTV in IMRT method. A total of thirty IMRT and 3DCRT plans were performed for evaluation of dosimetric parameters (for each patient both treatment plans, step and shoot IMRT and 3DCRT with 6, 10 and 18MV energies) were done. The integral dose was calculated as the mean- dose times the volume of the structure. The mean integral dose (ID) received by rectum for 3DCRT was almost 1.01% greater than IMRT while in bladder mean value of ID for IMRT was approximately 1.68% higher than 3DCRT. For PTV in IMRT the ID of target volume had the biggest value (1.14%) compared to that of 3DCRT. Dose conformity in PTV volume in S.A.S and 3DCRT was almost equal. The same outcome was achieved in homogeneity index. The results of this study shows that IMRT method leads to adequate target dose coverage while the prescribed dose for this modality is higher than 3DCRT. IMRT has the ability of increasing the maximum dose to tumor region and improves conformity and homogeneity indexes in target volume and also reduces dose to OAR