Channel Impulse Response-based Distributed Physical Layer Authentication

In this preliminary work, we study the problem of {\it distributed} authentication in wireless networks. Specifically, we consider a system where multiple Bob (sensor) nodes listen to a channel and report their {\it correlated} measurements to a Fusion Center (FC) which makes the ultimate authentication decision. For the feature-based authentication at the FC, channel impulse response has been utilized as the device fingerprint. Additionally, the {\it correlated} measurements by the Bob nodes allow us to invoke Compressed sensing to significantly reduce the reporting overhead to the FC. Numerical results show that: i) the detection performance of the FC is superior to that of a single Bob-node, ii) compressed sensing leads to at least $20\%$ overhead reduction on the reporting channel at the expense of a small ($<1$ dB) SNR margin to achieve the same detection performance.Comment: 6 pages, 5 figures, accepted for presentation at IEEE VTC 2017 Sprin

Unveiling the Connection Between Malware and Pirated Software in Southeast Asian Countries: A Case Study

Pirated software is an attractive choice for cybercriminals seeking to spread malicious software, known as malware. This paper attempts to quantify the occurrence of malware concealed within pirated software.We collected samples of pirated software from various sources from Southeast Asian countries, including hard disk drives, optical discs purchased in eight different countries, and online platforms using peerto- peer services. Our dataset comprises a total of 750 pirated software samples. To analyze these samples, we employed seven distinct antivirus (AV) engines. The malware identified by the AV engines was classified into four categories: adware, Trojans, viruses, and a miscellaneous category termed others. Our findings reveal that adware and Trojans are the most prevalent types of malware, with average infection rates of 34% and 35%, respectively, among our pirated software samples. Notably, our evaluation of AV detection performance highlights variations in sensitivity, ranging from a high of 132% to a low of 30% across all AV engines. Furthermore, upon installing pirated software, the most adversely affected operating system settings are the firewall and user account control configurations. Given the potential for malware to steal information or create malicious backdoors, its high prevalence within pirated software poses a substantial security risk to end users

Incoherent and Online Dictionary Learning Algorithm for Motion Prediction

Accurate model development and efficient representations of multivariate trajectories are crucial to understanding the behavioral patterns of pedestrian motion. Most of the existing algorithms use offline learning approaches to learn such motion behaviors. However, these approaches cannot take advantage of the streams of data that are available after training has concluded, and typically are not generalizable to data that they have not seen before. To solve this problem, this paper proposes two algorithms for learning incoherent dictionaries in an offline and online manner by extending the offline augmented semi-non-negative sparse coding (ASNSC) algorithm. We do this by adding a penalty into the objective function to promote dictionary incoherence. A trajectory-modeling application is studied, where we consider the learned atoms of the dictionary as local motion primitives. We use real-world datasets to show that the dictionaries trained by the proposed algorithms have enhanced representation ability and converge quickly as compared to ASNSC. Moreover, the trained dictionaries are well conditioned. In terms of pedestrian trajectory prediction, the proposed methods are shown to be on par (and often better) with the state-of-the-art algorithms in pedestrian trajectory prediction

Discriminatory dissolution testing for liquisolid compacts containing a poorly water-soluble drug (Hydrochlorothiazide)

Drug release from liquisolid compacts is dependent on several variables and changes in experimental parameters, like drug loading and the type and quantity of the carrier material, which affect the dissolution rate, significantly. Therefore, a dissolution method is needed that can discriminate among in vitro release profiles of liquisolid compacts of varying nature. The objective of this study was to develop and validate a discriminatory dissolution testing method for liquisolid compacts of hydrochlorothiazide (HCTZ) to evaluate the effect of formulation and process variables on dissolution rate. Various experimental conditions were optimized, and the method was validated according to USP and ICH guidelines for different parameters like linearity, specificity, accuracy, precision, and stability of solution. Analysis of dissolution samples was carried out by high-performance liquid chromatography (HPLC). The discriminatory nature of the method was confirmed by determining dissolution rates of liquisolid compacts of HCTZ prepared with different load factors. A model-independent approach was applied for comparison of different dissolution profiles. Based on a screening study, USP apparatus I (basket method) was selected. The best in vitro dissolution profile was obtained using purified water containing Tween-80 (0.5% v/v) as the dissolution medium (900 mL), stirred at 75 rpm. Complete dissolution (99.83 ± 1.03%) was achieved within 60 min and dissolution media had no interference with sample analysis. HCTZ exhibited a linear response (r2 = 0.9974) in the selected dissolution medium and showed accurate results (98%–100%) in the concentration rage of 80%–120% of the dose. All validation parameters were found in acceptable range (%RSD > 2), and drug samples prepared in dissolution medium were stable for the specified period. Comparison of dissolution profiles in the official and developed media showed significant differences in f1 and f2 values. The developed dissolution test exhibited higher discriminative capacity in differentiating release profiles of HCTZ and can be applied during formulation development and quality control analysis of liquisolid compacts

Vitamin D Deficiency in HCV Antiviral Treatment Responders versus Non-Responders

Background: Hepatitis C virus (HCV) is a major cause of chronic liver disease (CLD). Pakistan has a high burden of infectious diseases, including HCV. Its prevalence varies according to geographic regions in the country from about 2·4% to 6·5%. The objective of the study was to compare the frequency of vitamin D deficiency in responders and non-responders of antiviral treatment for chronic hepatitis C.Material and Methods: This comparative cross-sectional study was conducted in Hepatitis Clinic, Jinnah hospital, Lahore from 20th May to 20th November 2013. After ethical approval, participants were selected by using purposive non-probability sampling, 52 responder patients i.e. who were labeled negative for HCV RNA by PCR after 12 weeks of antiviral treatment and 52 non-responder patients were included in this study. Data was collected by using pretested structured questionnaire. Vitamin D3 levels were measured by ELISA and a cut-off value of below 30ng/ml was labeled as Vitamin D deficiency. SPSS version 21 was used to analyze data with p value less than 0.05 taken as statistically significant.Results: Out of 104 patients (mean age 35±8.1 years), 61.5% were males and 38.5 % were females. There was a significant difference in frequency of vitamin D deficiency in treatment responder group when compared to non-responders (p = 0.016). Mean level of vitamin D was 21.8±10.8ng/ml in responders whereas it was 15.6±7.5 in non-responders with a statistically significant difference (p = 0.001).Conclusion: This study concludes that there is a significant vitamin D deficiency among treatment non-responders as compared to treatment responders in patients with chronic hepatitis C

A new sensitive HPLC/UV method for simultaneous determination of paclitaxel, sorafenib and omeprazole in standard solutions and spiked plasma: Application to in-vitro and in-vivo evaluation of paclitaxel polymeric nanoformulations

Purpose: To develop a simple, novel, sensitive and rapid reverse phase high performance liquid chromatographic method for simultaneous determination of paclitaxel, sorafenib and omeprazole in standard solutions and spiked human plasma and its application to the in-vitro and in-vivo evaluation of paclitaxel polymeric nanoparticle formulations.Methods: The method was tested for the assessment of paclitaxel, omeprazole and sorafenib using tamoxifen citrate as internal standard. The analysis was performed at a wavelength of 235 nm using Thermo HS C18 column, 40 °C column oven temperature, acetonitrile and water (70:30 v/v, pH 3.37 adjusted with phosphoric acid) as a mobile phase and at a flow rate of 0.8 ml/min. All analytes were extracted by simple protein precipitation method using acetonitrile. The linearity was assessed in the concentration range of 1 - 2000 ng/mL for paclitaxel, omeprazole and sorafenib.Results: The developed chromatographic method effectively separated omeprazole, paclitaxel, sorafenib and IS with retention time of 3.93, 5.18, 6.43 and 9.93 min, respectively. The chromatograms of the three target compounds and IS showed good resolution and peak separation. The LOD of the method was 1, 5 and. 5 ng/mL while the LOQ was 2, 7.5 and 10 ng/mL, for paclitaxel, sorafenib and omeprazole, respectively.Conclusion: The proposed RP-HPLC–UV method for the assessment of paclitaxel, sorafenib and omeprazole in standard solutions and spiked plasma is simple, economical, sensitive and robust. The method is also suitable for the analysis of paclitaxel in nanoformulations and for its pharmacokinetic studies in an animal model

Visible light driven doped CeO2 for the treatment of pharmaceuticals in wastewater: A review

The high-level contamination of pharmaceuticals in aquatic environment, and their toxicities is a serious issue. This review highlights the use of ceria photocatalyst for treatment of pharmaceuticals. Cerium oxide (CeO2) with high oxygen storage, ecofriendly properties, reusability, and photostability contrary to other metal oxides photocatalysts is reportedly a better choice. However, ceria with high band gap energy show photoactivity mainly under UV light. This review highlights pharmaceuticals contamination in water, their contamination level, and toxicities and properties of CeO2 and different approaches used for extending photoactivity of CeO2 under visible irradiation. Metals and non-metals doping is found to promote greatly photoactivity of CeO2 under visible irradiation by narrowing band gap, shift in absorption edge to visible region, crystal defects and yield of oxygen vacancy, lower recombination of conduction band electrons and valence band holes and increasing surface area. The visible irradiation of CeO2 is found to produce hydroxyl radical (OH) and superoxide radical (O2 –) which contribute in pharmaceuticals degradation. The electron paramagnetic resonance spectroscopy and radical scavenger studies confirmed the formation of reactive oxygen species from CeO2 photoactivation. Doping was found to incorporate into the lattice of CeO2 and improve reusability and stability of CeO2 photocatalyst. The suggested mechanisms involved in the treatment of pharmaceuticals through OH and O2 – is discussed. Furthermore, the outlook and future challenges in the use CeO2 for photocatalytic degradation of pharmaceuticals and other organic pollutants are evaluated

Validated and optimized RP-HPLC method for the simultaneous quantification of meloxicam and its major metabolites in biological fluids with liquid liquid and solid phase extraction technique

Meloxicam is the most commonly prescribed non-steroidal anti-inflammatory drug. In this study, a simple, rapid and cost-effective method for the analysis of meloxicam and its major metabolites (5-hydroxy meloxicam and 5-carboxy meloxicam) in biological fluids (human plasma, urine and saliva) was developed and validated using RP-HPLC coupled with UV detector. The samples were analyzed by injecting 20 μl into the HPLC system using supelco analytical C18 (150 mm ×4.6 mm, 5 μm) column, protected by a C18 (30 mm×4.6 mm, 10 μm) Perkin Elmer, guard column. The mobile phase methanol: TFA (0.05% aqueous solution) in 60:40%v/v was pumped with a flow rate of 1.3 mL/min at ambient temperature and the eluents were checked at 353nm using Piroxicam as internal standard. Meloxicam and the metabolites were extracted from biological fluids using dichloromethane and the percent recovery for meloxicam, 5-hydroxy meloxicam and 5- carboxy meloxicam were 98.8%, 97.3%, 97% in plasma, 99%, 98.6%, 95.1% in urine and 95.8%, 92.9%, 92.7% in saliva, respectively. The limits of detection of meloxicam, 5-hydroxy meloxicam and 5-carboxy meloxicam were 3 ng, 10 ng and 8 ng, whereas limit of quantification were 9 ng, 30 ng and 25 ng, respectively. The method was linear over the concentration range of 10 - 2000 ng/mL for meloxicam, 30 - 1000 ng/mL, 25 - 1000 ng/mL for 5-hydroxy meloxicam and 5-carboxy meloxicam, respectively. The developed method was validated according to standard guidelines, various experimental parameters and chromatographic conditions such as mobile phase composition, flow rate, linearity, accuracy, precision, sensitivity etc. were optimized and were successfully applied for the pharmacokinetic studies in the plasma samples of the healthy human volunteers