Assembling nanostructures from DNA using a composite nanotweezers with a shape memory effect

The article demonstrates a technique for fabricating a structure with the inclusion of suspended DNA threads and manipulating them using composite nanotweezers with shape memory effect. This technique could be suitable for stretching of nanothin DNA-like conductive threads and for measuring their electrical conductivity, including the I-V characteristic directly in the electron microscope chamber, where the nanotweezers provide a two-sided clamping of the DNA tip, giving a stable nanocontact to the DNA bundle. Such contact, as a part of 1D nanostructure, is more reliable during manipulations with nanothreads than traditional measurements when a nanothread is touched by a thin needle, for example, in a scanning tunnel microscope.Comment: To be presented on IEEE 3M-NANO 201

Buy-out of pets because of their unproper treatment under civil legislation of Russia and post-soviet countries

The article deals with one of the compulsory methods of ownership right termination - the buy-out of pets if they are treated improperly. The authors draw attention to the specifics of this reason, which is associated with the buy-out subject, i.e. with an animal. They performed the comparative analysis of "pet improper treatment" and "cruel animal treatment" concepts, the problem of their differentiation is studie

Protein Dynamics Control of Electron Transfer in Photosynthetic Reaction Centers from Rps. Sulfoviridis

In the cycle of photosynthetic reaction centers, the initially oxidized special pair of bacteriochlorophyll molecules is subsequently reduced by an electron transferred over a chain of four hemes of the complex. Here, we examine the kinetics of electron transfer between the proximal heme c-559 of the chain and the oxidized special pair in the reaction center from Rps. sulfoviridis in the range of temperatures from 294 to 40 K. The experimental data were obtained for three redox states of the reaction center, in which one, two, or three nearest hemes of the chain are reduced prior to special pair oxidation. The experimental kinetic data are analyzed in terms of a Sumi–Marcus-type model developed in our previous paper,1 in which similar measurements were reported on the reaction centers from Rps. viridis. The model allows us to establish a connection between the observed nonexponential electron-transfer kinetics and the local structural relaxation dynamics of the reaction center protein on the microsecond time scale. The activation energy for relaxation dynamics of the protein medium has been found to be around 0.1 eV for all three redox states, which is in contrast to a value around 0.4–0.6 eV in Rps. viridis.1 The possible nature of the difference between the reaction centers from Rps. viridis and Rps. sulfoviridis, which are believed to be very similar, is discussed. The role of the protein glass transition at low temperatures and that of internal water molecules in the process are analyzed.España, Ministerio de Educación y Ciencia BFU2004-04914-C02-01/BMCJunta de Andalucía PAI CVI-26

Ti2NiCu Based Composite Nanotweezers with a Shape Memory Effect and its Use for DNA Bunches 3D Manipulation

The DNA molecules were controllable deposited on graphene and thin graphite films and visualized using AFM. The mechanical micro- and nanotools, such as nanotweezers with shape memory effect controlled by heating were designed and tested. A technique for fabricating a structure with the inclusion of suspended DNA threads and manipulating those using composite nanotweezers with shape memory effect was suggested.Comment: arXiv admin note: text overlap with arXiv:1811.0294

Potentiality of Charcoal as a Dendrochronological and Paleoclimatic Archive: Case Study of Archaeological Charcoal from Southeastern Altai, Russia

Archaeological charcoal from ancient nomad iron-smelting furnaces collected in the highland southeastern Russian Altai has great potential as a material for tree ring analysis. Dendrochronological dating was applied to 355 viable samples (>80% of the 448 collected ones), prepared using a new protocol. Individual tree ring series of 155 (~43%) samples were used to construct nine floating chronologies from 76 to 290 rings long. The archaeological and radiocarbon data on charcoal that fueled the hearths of the Kosh-Agach type bracket the floating tree ring chronologies between the second and tenth centuries AD. The results demonstrate that long tree ring “steppe” chronologies can be obtained for intermontane basins in the arid zone of Southern Siberia, using the analysis of charcoal samples. A strong climate signal imprinted in the annual growth of trees allowed for crossdating samples with relatively few rings. The revealed common climate signal for larches from different locations indicates similar paleoclimate conditions of their growth despite the strong modern southeastward aridization trend in the region, which was not so pronounced ca. 1.5 ka ago. The further matching of these chronologies to the calendar timeline will provide reference for the precise comparison of climatic conditions in the floors of intermontane basins and in the flanking mountains. © 2023 by the authors.Russian Science Foundation, RSFThe study was supported by grant 22-27-00454 from the Russian Science Foundation

Strongly localized polaritons in an array of trapped two-level atoms interacting with a light field

We propose a new type of spatially periodic structure, i.e. polaritonic crystal (PolC), to observe a "slow"/"stopped" light phenomenon due to coupled atom-field states (polaritons) in a lattice. Under the tightbinding approximation, such a system realizes an array of weakly coupled trapped two-component atomic ensembles interacting with optical field in a tunnel-coupled one dimensional cavity array. We have shown that the phase transition to the superfluid Bardeen-Cooper-Schrieffer state, a so-called (BCS)-type state of low branch polaritons, occurs under the strong coupling condition. Such a transition results in the appearance of a macroscopic polarization of the atomic medium at non-zero frequency. The principal result is that the group velocity of polaritons depends essentially on the order parameter of the system, i.e. on the average photon number in the cavity array.Comment: 16 pages, 6 figure

NOVEL APPROACHES TO TREATING NONSPECIFIC LOW BACK PAIN

Objective: to evaluate the impact of therapy with chondroitin sulfate (CS) and glucosamine (GA) on the clinical manifestations of low back pain (LBP).Subjects and methods. A multicenter open-label observational prospective study was conducted in 22 cities of Russia (46 centers) to investigate the efficacy of a combination of CS and GA in the outpatient treatment of nonspecific LBP. A total of 9761 patients were enrolled in the study that was completed by 8546 patients. Therapeutic efficiency was evaluated from changes in pain intensity during movement and at rest, by using the visual analogue scale. The Oswestry disability index, an global physician and patient assessment of therapeutic efficiency, and a daily need for nonsteroidal anti-inflammatory drugs (NSAIDs) were taken into account as additional criteria for efficiency evaluation.Results and discussion. The multicenter open-label observational study established the efficacy of a combination of CS and GA in treating nonspecific LBP: relief in pain during movement and at rest, functional improvement, and a reduction in the daily need for NSAIDs. The patients and physicians highly assessed therapeutic efficiency. The combination of CS and GA was also noted to be well tolerated. The findings may suggest that this combination may be a promising tool to treat LBP and gives proof to the expediency of its use in randomized placebo-controlled studies

The role of obstetric pessary and micronized progesteron in early preterm birth prevention in patients with multiple pregnancy

Background. Multiple pregnancy is a well-established risk factor for preterm birth. Prevention of early termination of pregnancy is a priority problem in obstetric practice.The aim. To evaluate the role of an obstetric pessary and micronized progesterone in the prevention of early preterm labor in patients with multiple pregnancies.Materials and methods. A prospective controlled study was conducted with the inclusion of 146 pregnant women with multiple pregnancies, which, depending on the methods of treatment, were divided into three groups: Group I (n = 67) – pregnant women who received micronized progesterone in combination with an obstetric pessary; Group II (n = 57) included women who received micronized progesterone; Group III (n = 22) consisted of patients with multiple pregnancies without therapy.Results. In Group I, the complex of an obstetric pessary and micronized progesterone allowed to reduce the frequency of preterm birth by 2.3 times (p = 0.008) in comparison with Group III, the frequency of births at gestational age ≤ 34 weeks – by 8.1 times (p = 0.005) in compared with Group III and 2.7 times (p < 0.01) compared with Group II. In 70.4 % of pregnant women, the use of a complex of an obstetric pessary with micronized progesterone made it possible to prevent the formation of isthmiccervical insufficiency, which, according to sonography, was expressed in the dynamics of the utero-cervical angle towards a more obtuse one.Conclusion. The use of an obstetric pessary with micronized progesterone made it possible to reduce the risks of isthmic-cervical insufficiency by 7.7 % compared with patients who received only micronized progesterone therapy, and by 17.1 % compared with pregnant women who did not receive therapy