DFT Study of Hexagonal Boron Nitride Electronic Properties Using Different Types of Exchange Correlation Functionals

840-845Density functional theory (DFT) description of electronic structure and related properties offer significant accuracy with low cost. Unfortunately, most of these calculations based on LDA and GGA Exchange-Correlation (XC) functionals are underestimating the energy band gap. Hybrid functionals seem promising candidates for band gap values enhancement. Hexagonal Boron Nitride (h-BN) is one of the important members of the graphene-like two-dimensional honeycomb structure family which is of great importance both for science and technology. Experimentally, there is convincing evidence for an indirect wide bandgap of about 6 eV. We present in this work a systematic DFT study using different types of Exchange-Correlation (XC) functionals to find out their accuracy to estimate the h-BN band gap along with its band structure and density of states. We tested five types of different functionals to study the band structure and density of states of a single-layer h-BN. Small differences have been noticed regarding band structure and density of state details. Nevertheless, HSE03 deduced the band gap accurately within a 3.4% deviation from the experimental value compared with LDA which showed a 24.4% error

Effect of serum cystatin C in early diabetic nephropathy in type 2 Iraqi diabetic patients

Objective This study aimed to find the effect of serum Cystatin C in early diabetic nephropathy. Method This study was conducted in Al Kindy Teaching Hospital during the period from December, 2015 to June, 2016. The study included 90 subjects (30 males and 30 females) with diabetic type 2 and 30 healthy control. Age is between 30 and 70 years. Patients were with no history of liver disease, thyroid or other endocrine diseases through clinical interviewing. They were divided in to three groups. 30 healthy controls, 30 patients with type 2 diabetes mellitus with no albuminuria (albumin excretion in urine 30 μg/ml ). Results There were no significant differences in age, body mass index (BMI) among the studied groups (p > 0.05). Serum Cystatin C levels showed significant difference (p < 0.001) among studied groups, it was significantly higher in micro albuminuria than the other two groups. There was highly significant positive correlation between Cystatin C and serum creatinine (r = 0.697, p < 0.001), and a significant negative correlation between Cystatin C and GFR (r = − 0.455, p = 0.011) and show significant positive correlation between Cystatin C and urine albumin (r = 0.526, p = 0.003 ) in type 2 diabetic patients with micro albuminuria. Conclusion Cystatin C is negatively correlated with the amount of GFR, so that Cystatin C considered reliable and sensitive marker for identifying changes in GFR. In type 2 diabetes mellitus with micro albuminuria serum Cystatin C level considered predict marker for renal failure

Challenges, alternatives, and paths to sustainability: Better public health promotion using social networking pages as key tools

This paper discusses the possibility of promoting public health and implementing educational health services using Facebook. We discuss the challenges and strengths of using such a platform as a tool for public health care systems from two different perspectives, namely, the view of IT developers and that of physicians. We present a new way of evaluating user interactivity in health care systems from tools provided by Facebook that measure statistical traffic in the Internet. Findings show that Facebook is a very promising tool in promoting e-health services in Web 2.0. Results from statistical traffic show that a Facebook page is more efficient than other pages in promoting public health

Randomly Partitioned Encryption for Cloud Databases

International audienceWith the current advances in Cloud Computing, outsourcing data has never been so tempting. Along with outsourcing a database comes the privacy versus performance discussion. Order-Preserving Encryption (OPE) is one of the most attractive techniques for database encryption since it allows to execute range and rank queries efficiently without decrypting the data. On the other hand, people are reluctant to use OPE-based techniques in practice because of their vulnerability against adversaries with knowledge of the domain, its frequency distribution and query logs. This paper formally defines three real world driven attacks, called Domain Attack, Frequency Attack and Query Log Attack, typically launched by an honest-but-curious database or systems administrator. We also introduce measures to capture the probability distribution of the adversary’s advantage under each attacker model. Most importantly, we present a novel technique called Randomly Partitioned Encryption (RPE) to minimize the adversary’s advantage. Finally, we show that RPE not only withstands real world database adversaries, but also shows good performance that is close to state-of-art OPE schemes for both, read- and write-intensive workloads

Enforcing Privacy in Cloud Databases

Outsourcing databases, i.e., resorting to Database-as-a-Service (DBaaS), is nowadays a popular choice due to the elasticity, availability, scalability and pay-as-you-go features of cloud computing. However, most data are sensitive to some extent, and data privacy remains one of the top concerns to DBaaS users, for obvious legal and competitive reasons.In this paper, we survey the mechanisms that aim at making databases secure in a cloud environment, and discuss current pitfalls and related research challenges