Filter List Generation for Underserved Regions

Filter lists play a large and growing role in protecting and assisting web users. The vast majority of popular filter lists are crowd-sourced, where a large number of people manually label resources related to undesirable web resources (e.g., ads, trackers, paywall libraries), so that they can be blocked by browsers and extensions. Because only a small percentage of web users participate in the generation of filter lists, a crowd-sourcing strategy works well for blocking either uncommon resources that appear on "popular" websites, or resources that appear on a large number of "unpopular" websites. A crowd-sourcing strategy will perform poorly for parts of the web with small "crowds", such as regions of the web serving languages with (relatively) few speakers. This work addresses this problem through the combination of two novel techniques: (i) deep browser instrumentation that allows for the accurate generation of request chains, in a way that is robust in situations that confuse existing measurement techniques, and (ii) an ad classifier that uniquely combines perceptual and page-context features to remain accurate across multiple languages. We apply our unique two-step filter list generation pipeline to three regions of the web that currently have poorly maintained filter lists: Sri Lanka, Hungary, and Albania. We generate new filter lists that complement existing filter lists. Our complementary lists block an additional 3,349 of ad and ad-related resources (1,771 unique) when applied to 6,475 pages targeting these three regions. We hope that this work can be part of an increased effort at ensuring that the security, privacy, and performance benefits of web resource blocking can be shared with all users, and not only those in dominant linguistic or economic regions

Is It Possible to Reverse the Storage-Induced Lesion of Red Blood Cells?

Cold-storage of packed red blood cells (PRBCs) in the blood bank is reportedly associated with alteration in a wide range of RBC features, which change cell storage each on its own timescale. Thus, some of the changes take place at an early stage of storage (during the first 7 days), while others occur later. We still do not have a clear understanding what happens to the damaged PRBC following their transfusion. We know that some portion (from a few to 10%) of transfused cells with a high degree of damage are removed from the bloodstream immediately or in the first hour(s) after the transfusion. The remaining cells partially restore their functionality and remain in the recipient’s blood for a longer time. Thus, the ability of transfused cells to recover is a significant factor in PRBC transfusion effectiveness. In the present review, we discuss publications that examined RBC lesions induced by the cold storage, aiming to offer a better understanding of the time frame in which these lesions occur, with particular emphasis on the question of their reversibility. We argue that transfused RBCs are capable (in a matter of a few hours) of restoring their pre-storage levels of ATP and 2,3-DPG, with subsequent restoration of cell functionality, especially of those properties having a more pronounced ATP-dependence. The extent of reversal is inversely proportional to the extent of damage, and some of the changes cannot be reversed

Sticking of H_2 on Oxygen-Covered Surface of Vanadium Doped with Oxygen to Various Bulk Concentrations

The sticking probability of Hz on the surface of polycrystalline V covered with oxygen was examined as a function of oxygen concentration in the bulk metal (0.4 to 3.3 at.%) at specimen temperatures from 200 to 1000℃. At all temperatures examined, the sticking probability was strongly dependent on the oxygen concentration in the bulk.Such correlation between the reaction rate of Hz on the surface and the oxygen concentration in the bulk was attributed to the dependence of concentration of oxygen vacancies (holes in surface oxygen coverage) on the oxygen bulk concentration. The values of sticking probability were relatively high even at the oxygen bulk concentration of 3.3 at.%; the oxygen coverage on vanadium was rather "holey" even at the oxygen concentration close to the solubility limit. The activation energy for H_2 dissociation on such holes in the coverage was evaluated to be 10 kJ/mol H_2

Determination of Young's modulus of Sb2S3 nanowires by in situ resonance and bending methods

Publisher Copyright: © 2016 Jasulaneca et al.In this study we address the mechanical properties of Sb2S3 nanowires and determine their Young's modulus using in situ electricfield- induced mechanical resonance and static bending tests on individual Sb2S3 nanowires with cross-sectional areas ranging from 1.1·104 nm2 to 7.8·104 nm2. Mutually orthogonal resonances are observed and their origin explained by asymmetric cross section of nanowires. The results obtained from the two methods are consistent and show that nanowires exhibit Young's moduli comparable to the value for macroscopic material. An increasing trend of measured values of Young's modulus is observed for smaller thickness samples.publishersversionPeer reviewe

Lumbar disc degeneration and genetic factors are the main risk factors for low back pain in women: the UK Twin Spine Study

Low back pain (LBP) is a common musculoskeletal disorder, but it is still unclear which individuals develop it. The authors examined the contribution of genetic factors, lumbar disc degeneration (LDD) and other risk factors in a female sample of the general population. Material an

Sputtering of Oxygen on Nb Surface by Hydrogen Ions

The rate of oxygen removal from an oxygen-doped Nb membrane by hydrogen ion sputtering was examined by measuring the change in the sticking coefficient of H2, α. First, the temperature dependence of α was measured at various oxygen concentrations to investigate correlation between bulk oxygen concentration and α. Then the oxygen concentration in the membrane was adjusted to 1.5 at%, and the surface of the membrane was irradiated by hydrogen ions of 600 eV at 1113 K. The change in α with sputtering time was measured, and the reduction in bulk oxygen concentration was estimated from the extent of change in α. The oxygen concentration decreased with increasing sputtering time by continuous surface segregation of oxygen and sputtering. The sputtering yield of oxygen on the Nb membrane surface was evaluated to range from 0.012 to 0.036

Fabrication and Characterization of Double- and Single-Clamped CuO Nanowire Based Nanoelectromechanical Switches

Funding Information: This research was funded by the European Regional Development Fund (project no. 1.1.1.1/16/A/256, ?Creation of nanoelectromechanical switches?). Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Electrostatically actuated nanoelectromechanical (NEM) switches hold promise for operation with sharply defined ON/OFF states, high ON/OFF current ratio, low OFF state power consumption, and a compact design. The present challenge for the development of nanoelectromechanical system (NEMS) technology is fabrication of single nanowire based NEM switches. In this work, we demonstrate the first application of CuO nanowires as NEM switch active elements. We develop bottom-up and top-down approaches for NEM switch fabrication, such as CuO nanowire synthesis, lithography, etching, dielectrophoretic alignment of nanowires on electrodes, and nanomanipulations for building devices that are suitable for scalable production. Theoretical modelling finds the device geometry that is necessary for volatile switching. The modelling results are validated by constructing gateless double-clamped and single-clamped devices on-chip that show robust and repeatable switching. The proposed design and fabrication route enable the scalable integration of bottom-up synthesized nanowires in NEMS.publishersversionPeer reviewe

Construction and Performance Test of Apparatus for Permeation Experiments with Controlled Surfaces

A new apparatus was constructed to examine gas-, atom- and Plasma-driven permeation of hydrogen isotopes through group VA metal membranes with precisely controlled surface states. Absorption and desorption experiments are also possible. The new apparatus consists of two vacuum chambers, an upstream chamber and a downstream chamber, separated by a specimen membrane. Both chambers are evacuated by turbo-molecular pumps and sputter-ion pumps. The upstream chamber is equipped with Ta filaments serving as atomizers in atom-driven permeation experiments and cathodes in plasma-driven permeation experiments. The specimen membrane is formed into a tubular and electrically isolated from the chamber. Hence, ohmic heating of the membrane is possible, and this feature of the membrane is suitable for surface cleaning by high-temperature heating and impurity doping for the control of surface chemical composition through surface segregation. Both chambers were evacuated to 1x10-7 Pa after baking. The main component of residual gas was H2, and the partial pressures of impurity gases other than H2 were ca. 1x10-8 Pa. Gas- and atom-driven permeation experiments were successfully carried out with hydrogen gas for Nb membrane activated by heating in vacuum at 1173K. Superpermeation was observed in the atom-driven permeation experiments. Absorption experiments with a clean surface were also carried out. The surface was, however, cleaned only partially, because the temperature distribution was not uniform during high-temperature heating. Nevertheless, surface cleanliness was retained during absorption experiments under the present vacuum conditions. A new membrane assembly that will enable a uniform temperature distribution is now under construction

Extra tension at electrode-nanowire adhesive contacts in nano-electromechanical devices

We report a strong tangential component of the reaction force at electrode to nanowire adhesive contact which was previously established using electrostatic attraction. The reaction force tangential component absolute value was found to be comparable to or even bigger than the corresponding normal component. This effect is important for understanding of the mechanics of nano-electromechanical devices. Both the experiment and the corresponding theory are presented. Fitting of the obtained analytical solutions to experimental data was used to measure the reaction force acting at the contact for several nanowire-electrode configurations