Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Algorithm for emergency deletion of files by voice command

The Currently, there is a growing interest in various methods and means of protecting information, which is due to the growing number of crimes related to the violation of confidentiality of information, including through physical access to a computer. There are many ways to protect information from unauthorized access, such as physical security measures, password protection, and so on. However, a situation may arise when all defense lines have already been overcome and there is no other way to quickly block or destroy confidential information in any other way than with the help of a voice command. Thus, the topic of the article is relevant. The object of research is an information system containing confidential information. The subject of the research is the methods of emergency deletion of confidential information. The purpose of this article is to develop an algorithm for urgent deletion of files by voice command. In the course of the work, the algorithm for the emergency deletion of files by voice command was developed, which allows blocking the means of inputting information (keyboard and mouse) and deleting files located in a predetermined folder. The algorithm provides protection against accidental pronunciation of a voice command: before deleting files, a timer is first started, the time of which is pre-set by the user. During the duration of the timer, it is possible to cancel the deletion of files by entering a password, however, there is no way to access the information until the appropriate password is entered

Enhanced optomechanical interaction in the unbalanced interferometer

Quantum optomechanical systems enable the study of fundamental questions on quantum nature of massive objects. For that a strong coupling between light and mechanical motion is required, which presents a challenge for massive objects. In particular large interferometric sensors with low frequency oscillators are difficult to bring into quantum regime. Here we propose a modification of the Michelson-Sagnac interferometer, which allows to boost the optomechanical coupling strength. This is done by unbalancing the central beam-splitter of the interferometer, allowing to balance two types of optomechanical coupling present in the system: dissipative and dispersive. We analyse two different configurations, when the optomechanical cavity is formed by the mirror for the laser pump field (power-recycling), and by the mirror for the signal field (signal-recycling). We show that the imbalance of the beam splitter allows to dramatically increase the optical cooling of the test mass motion. We also formulate the conditions for observing quantum radiation-pressure noise and ponderomotive squeezing. Our configuration can serve as the basis for more complex modifications of the interferometer that would utilize the enhanced coupling strength. This will allow to efficiently reach quantum state of large test masses, opening the way to studying fundamental aspects of quantum mechanics and experimental search for quantum gravity.Comment: 12 pages, 6 figure

Numerical simulation of a turbulent pipe flow: FluidX3D LBM validation

The validation of the computational LBM code FliudX3D is presented on the example of turbulent flow in a pipe at two Reynolds numbers: 5300 and 37700, built on the bulk velocity, pipe diameter and kinematic viscosity. Due to the LBM approach, the code performance allows massive calculations to be performed in a short period of time with a good agreement with the literature data for the lower Reynolds number. However, the lack of the possibility to refine the computational grid leads to insufficient resolution of the turbulent boundary layer for the higher Reynolds number

Thrombin generation test for evaluation of antiplatelet treatment in patients with coronary artery disease after percutaneous coronary intervention

To study the possibility of using thrombin generation tests in platelet-rich and platelet-poor plasma for evaluation of dual antiplatelet therapy efficacy in patients with coronary artery disease (CAD), following percutaneous coronary intervention. Venous blood was analyzed from CAD patients aged 53–75 years who had undergone percutaneous coronary intervention with stenting within one year and had been receiving standard doses of clopidogrel and aspirin (75 and 75–100 mg per day, respectively). The control group comprised age- and sex-matched subjects without clinical signs of CAD who were not receiving these drugs. Thrombin generation tests were performed in platelet-rich and platelet-poor plasma. Intravascular platelet activation, induced platelet aggregation, and routine coagulation were evaluated. Antiplatelet treatment did not influence results of routine coagulation tests or intravascular platelet activation. The dual antiplatelet therapy affects collagen-induced platelet aggregation (44 ± 2.5 vs. 7.9 ± 2.6%, р = 10−7) and leads to decreases in endogenous thrombin potential (1900 ± 85 vs. 1740 ± 95 nM∙min, p = 0.0045), maximum thrombin concentration (134 ± 9.5 vs. 106 ± 6.5 nM, p = 4∙10−6), and increases in time to peak thrombin (27 ± 1.5 vs. 31 ± 2 min, p = 0.0012). Decreases in thrombin generation rate showed the highest statistical significance (13 ± 2 vs. 7.9 ± 0.8 nM/min, p = 10−8). Antiplatelet treatment did not alter thrombogram parameters for platelet-poor plasma

Pathomorphologic evaluation of intra-articular injections of soluble platelet‑rich plasma for treatment of experimental osteoarthritis

Introduction Non-surgical treatment of osteoarthritis is aimed at managing joint degeneration and inflammation to prolong the life of the original joint and delay total joint replacement. The objective was to pathomorphologically substantiate preclinical effectiveness of PRP in OA using comparative analysis of depleted plasma and serum. Material and methods The experiment was performed in 120 Wistar rats, divided into 4 groups. Osteoarthritis was simulated using an original method. Knee joint injection given to the animals after skin dissection under inhalation anesthesia and visual control two weeks later contained 0.05 ml PRP in group 1, 0.05 ml plasma in groups 2 and 0.05 ml blood serum in groups 3. The same volume of physiological saline solution was used for the injections produced for control animals. Injections were administered three times at 2-week intervals. Animals were sacrificed in groups of 10 at 2 weeks of each injection. Results The median MANKIN value scored 2.0 (1.0; 2.0) in group 1, 6.0 (5.0; 7.0) in group 2 and 7.0 (6.0; 7.0) in group 3 at 6 weeks. The median MANKIN value scored 7.5 (7.0, 8.0) in the control group. Statistically significant differences were determined between the groups at p < 0.001. Discussion Literature data on preclinical evaluation of the effectiveness of PRP therapy in biological models of OA are controversial. An original, low-traumatic functional method was used for simulating knee OA to reproduce major pathogenetic mechanisms in rats. Conclusion The findings suggested a pronounced therapeutic effect with improved morphofunctional features of the hyaline cartilage and MANKIN score of 2 at 6 days of intra-articular administration of modified PRP as compared with plasma and serum

Vorontsovite, (Hg5cu)\u3a36TLAs4S12, and ferrovorontsovite, (Fe5Cu)\u3a36TlAs4S12: The Tl- and Tl-Fe-analogues of galkhaite from the vorontsovskoe gold deposit, northern Urals, Russia

Two new mineral species, vorontsovite, ideally (Hg5Cu)TlAs4S12, and ferrovorontsovite, ideally (Fe5Cu)TlAs4S12, the Tl- and Tl&ndash;Fe-analogues of galkhaite, respectively, have been discovered at the Vorontsovskoe gold deposit, Northern Urals, Russia. They occur as anhedral grains up to 0.5 mm (vorontsovite) and 0.2 mm (ferrovorontsovite) embedded in a calcite-dolomite matrix. The chemical composition of vorontsovite (wt %) is: Hg 35.70, Fe 5.36, Zn 1.26, Cu 3.42, Ag 0.64, Tl 11.53, Cs 0.35, Pb 0.04, As 15.98, Sb 2.35, Te 0.41, S 22.70, Se 0.02, total 99.76. The empirical formula, calculated on the basis of 23 atoms pfu, is: [(Hg3.02Fe1.63Zn0.33)&Sigma;4.98(Cu0.91Ag0.10)&Sigma;1.01](Tl0.96Cs0.04)&Sigma;1.00(As3.62Sb0.33Te0.05)&Sigma;4.00S12.01. The composition of ferrovorontsovite (wt %) is: Hg 25.13, Fe 9.89, Zn 1.16, Cu 3.95, Ag 0.45, Tl 12.93, Cs 0.44, Pb 0.04, As 17.83, Sb 2.15, Te 0.40, S 24.91, total 99.28. The empirical formula, calculated on the basis of 23 atoms pfu, is: [(Fe2.74Hg1.94Zn0.27)&Sigma;4.95(Cu0.96Ag0.06)&Sigma;1.02](Tl0.98Cs0.05)&Sigma;1.03(As3.68Sb0.27Te0.05)&Sigma;4.00S12.00. Both minerals are cubic, space group I-43m, with a = 10.2956(6) &Aring;, V = 1091.3(1) &Aring;3, Z = 2 (vorontsovite); and a = 10.2390(7) &Aring;, V = 1073.43(22) &Aring;3, Z = 2 (ferrovorontsovite). The crystal structures of both minerals were refined to R = 0.0376 (vorontsovite) and R = 0.0576 (ferrovorontsovite). Vorontsovite and ferrovorontsovite have been approved by the IMA-CNMNC under the numbers 2016-076 and 2017-007, respectively. The first one is named after the type locality, but also honors the mining engineer Vladimir Vasilyevich Vorontsov. The second is named for its chemical composition, as the Fe-analogue of the first. Both species are isostructural with galkhaite, being its Tl- and Tl&ndash;Fe analogues, respectively, and forming altogether the galkhaite group

Successful Charge–Discharge Experiments of Anthraquinone-Bromate Flow Battery: First Report

The proposed anthraquinone-bromate cell combines the advantages of anthraquinone-bromine redox flow batteries and novel hybrid hydrogen-bromate flow batteries. The anthraquinone-2,7-disulfonic acid is of interest as a promising organic negolyte due its high solubility, rapid kinetics of electrode reactions and suitable redox potentials combined with a high chemical stability during redox reactions. Lithium or sodium bromates as posolytes provide an anomalously high discharge current density of order ~A cm−2 due to a novel autocatalytic mechanism. Combining these two systems, we developed a single cell of novel anthraquinone-bromate flow battery, which showed a power density of 1.08 W cm−2, energy density of 16.1 W h L−1 and energy efficiency of 72% after 10 charge–discharge cycles