An investigation into the efficiency of forensic data erasure tools for removable usb flash memory storage devices

Securely erasing data is of key importance to anyone that is concerned with the security of their sensitive information, whether an individual or an organization. Simply deleting the data in question or formatting the storage device is not enough to ensure that the data cannot be recovered. Furthermore, with the uptake of Universal Serial Bus drives (USBs) flash memory based storage devices have replaced previous portable secondary storage media. Therefore, it is of a major concern whether these tools and products developed for securely erasing data secondary storage Hard Disk Drives (HDDs) would be as efficient when targeting the USB flash memory storage devices. With a wide range of open source and commercial products available on the market, all claiming, among other things, to be able to securely delete your data, it is quite a difficult task for the consumer to pick the most efficient product. This paper therefore discusses the results of experiments conducted with both the open source and commercial tools which claim to securely delete data off USB flash memory storage devices

An Investigation Into The Efficiency Of Forensic Data Erasure Tools For Removable Usb Flash Memory Storage Devices

Securely erasing data is of key importance to anyone that is concerned with the security of their sensitive information, whether an individual or an organization. Simply deleting the data in question or formatting the storage device is not enough to ensure that the data cannot be recovered. Furthermore, with the uptake of Universal Serial Bus drives (USBs) flash memory based storage devices have replaced previous portable secondary storage media. Therefore, it is of a major concern whether these tools and products developed for securely erasing data secondary storage Hard Disk Drives (HDDs) would be as efficient when targeting the USB flash memory storage devices. With a wide range of open source and commercial products available on the market, all claiming, among other things, to be able to securely delete your data, it is quite a difficult task for the consumer to pick the most efficient product. This paper therefore discusses the results of experiments conducted with both the open source and commercial tools which claim to securely delete data off USB flash memory storage devices

Measurement of the complex polar magneto-optical Kerr effect using weak measurement

Polar magneto-optical Kerr effect (PMOKE) is one of the most widely being applied magneto-optical Kerr effects (MOKE) due to the induced complex MOKE signal, consisting of the Kerr rotation angle and the ellipticity, is very sensitive to the magnetization component perpendicular to the magnetic surface. However, the Kerr rotation angle and the ellipticity invariably coexist and pose a challenge in their separation. This dual presence plays a pivotal role in defining the light intensity detected, ultimately restricting the advancements in the measurement precision. In this paper, we propose a weak measurement (WM) scheme to measure the complex MOKE in the pure polar configuration. Unlike the traditional MOKE or WM method using a quarter-wave-plate to measure the Kerr rotation angle and the ellipticity separately, we realize the simultaneous measurement of these two parameters in a single WM process using two new pointers, which possesses a larger linear response region compared with the previous amplified shift pointer. The measurement precision for the complex PMOKE angle reaches to $10^{-4}$ deg in our experiment. Besides, the complex magneto-optical constant Q is also calculated. This work is of great significance for the measurement of the complex PMOKE with high efficiency, ultra-precision, low cost, and is an important attempt to obtain complex physical quantities using WM

Characterization of memory cytotoxic t lymphocyte responses in chronic hiv-1 infected individuals

The three stages of untreated human immune deficiency virus type 1 (HIV-1) infection are acute HIV infection, chronic HIV infection, and acquired immunodeficiency syndrome (AIDS). Combination antiretroviral therapy (cART) is effective in treating chronic HIV infection but fails to completely clear the virus. Mutations in HIV epitopes recognized by cytotoxic T lymphocytes (CTL) could be a major contributing factor because they result in T cell mediated immune responses with limited effectiveness. In the absence of cART, it is the viral evolution within an individual during the course of infection under the pressure of host immune response that allows the virus to persist. To better understand viral pathogenesis and develop an effective HIV treatment, it is important to identify and characterize the evolution of mutations occurring within HIV CTL epitopes. Here I mapped the evolution of HIV CTL epitopes in chronically infected HIV-1 donors. Specifically, I fist 1) identified memory HIV CTL epitopes to HIV gag antigens p17/p24 from contemporaneous viral isolates obtained from long term HIV infected individuals and then 2) compared CTL responses to epitope sequences from the early stages of infection versus sequences after over 10 years of treatment and viral evolution. Using MHC class-1 binding predictive algorithm, the viral mutation was found to exhibit an unexpected pattern, that the reservoir variants has a higher binding affinity than its founder variant. Making use of an IFN- ELISpot Assay, the fact that the MHC class-1 binding affinity does not equal to the actual elicited CTL response has been noticed. Overall, this study has a significance in public health as it provided important information on the ability of HIV to escape CD8+ T lymphocyte detection and potentially contribute to the cure of the disease

The Effect of Vegetation Enhancement on Particulate Pollution Reduction: CFD Simulations in an Urban Park

Vegetation in parks is regarded as a valuable way to reduce particulate pollution in urban environments but there is little quantitative information on its effectiveness. The aim of this study was to conduct on-site measurements and computational fluid dynamic (CFD) simulations to determine the aerodynamic and deposition effects of vegetation enhancement on particulate matter (PM) dispersions in an urban park in Xi’an, China. Initially, the airflow characteristics and deposition effects of vegetation were predicted and compared with measured air velocities and particulate pollution data to validate the numerical modeling. Then, associated coverage ratios and supplementary green areas (tree coverage ratio, crown volume coverage (CVC), and roof greening) were added to numerical simulations. After a series of numerical simulations and comparisons, results indicated that: (1) Numerical models with simplified vegetation method could reproduce the distribution of particulate matter concentrations in the real park environment; (2) with a tree coverage ratio >37.8% (or CVC > 1.8 m3/m2), the pedestrian-level PM2.5 could meet the World Health Organization’s air quality guidelines (IT-1) standards in the park; (3) roof greening on leeward buildings produced greater PM removal effects compared with windward buildings; and (4) the most economical and reasonable tree coverage ratio and CVC to reduce atmospheric PM in urban parks should be 30% and 1.8 m3/m2, respectively. These results are useful guidelines for urban planners towards a sustainable design of vegetation in urban parks

Challenges and Future Perspectives of Promising Biotechnologies for Lignocellulosic Biorefinery

Lignocellulose is a kind of renewable bioresource containing abundant polysaccharides, which can be used for biochemicals and biofuels production. However, the complex structure hinders the final efficiency of lignocellulosic biorefinery. This review comprehensively summarizes the hydrolases and typical microorganisms for lignocellulosic degradation. Moreover, the commonly used bioprocesses for lignocellulosic biorefinery are also discussed, including separated hydrolysis and fermentation, simultaneous saccharification and fermentation and consolidated bioprocessing. Among these methods, construction of microbial co-culturing systems via consolidated bioprocessing is regarded as a potential strategy to efficiently produce biochemicals and biofuels, providing theoretical direction for constructing efficient and stable biorefinery process system in the future

In Vitro and In Vivo Comparative Evaluation of a Shellac-Ammonium Paclitaxel-Coated Balloon versus a Benchmark Device

Objectives. The present study was designed to compare the characteristics and performance regarding drug delivery of a novel drug-coated balloon (DCB) to a benchmark device (Restore® versus SeQuent® Please) in an in vitro and in vivo model. Background. Although Restore® and SeQuent® are both paclitaxel-coated, they use different coating excipient, shellac-ammonium salt and iopromide, respectively. Preclinical study comparing these two different commercial DCBs regarding their characteristics and effects on early vascular response is sparse. Methods. Restore® and SeQuent® DCBs were scanned with electron microscopy for surface characteristic assessment. Both DCBs were transported in an in vitro vessel model for the evaluation of drug wash-off rate and particulate formation. Eighteen coronary angioplasties with either Restore® or SeQuent® DCBs were conducted in 6 swine (three coronary vessels each). Histopathological images of each vessel were evaluated for vessel injury. Results. The surface of Restore® DCB was smooth and evenly distributed with hardly visible crystal, while SeQuent® DCB showed a rougher surface with relatively larger apparent crystals. Restore® DCB had a lower drug wash-off rate and fewer large visible particles, compared to the SeQuent® DCB. No significant difference in mean injure score was found between Restore® and SeQuent® group. Conclusion. Our results suggest that Restore® is better in preclinical performance regarding less release of particles and lower drug wash-off rate as compared to SeQuent® Please. The Restore® DCB, using stable amorphous coating and shellac-ammonium salt as an excipient, appears to provide an advantage in drug delivery efficacy; however, further clinical studies are warranted

SAR Study and Molecular Mechanism Investigation of Novel Naphthoquinone-furan-2-cyanoacryloyl Hybrids with Antitumor Activity

A series of novel naphthoquinone-furan-2-cyanoacryloyl hybrids were designed; they were synthesized and preliminarily evaluated for their anti-proliferative activities in vitro against several cancer cell lines and normal cells. The most potent compound, 5c, inhibited the proliferation of HeLa cells (IC50 value of 3.10 ± 0.02 μM) and colony survival, and it induced apoptosis while having relatively weaker effects on normal cells. Compound 5c also triggered ROS generation and accumulation, thus partially contributing to the observed cell apoptosis. A Western blotting analysis demonstrated that compound 5c inhibited the phosphorylation of STAT3. Furthermore, a biolayer interferometry (BLI) analysis confirmed that compound 5c had a direct effect on STAT3, with a KD value of 13.0 μM. Molecular docking showed that 5c specifically occupied the subpockets in the SH2 domain, thereby blocking the whole transmission signaling process. Overall, this study provides an important structural reference for the development of effective antitumor agents