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1.
Nat Commun ; 15(1): 4146, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755123

RESUMEN

Sufficiently fast continuous measurements of the position of an oscillator approach measurements projective on position eigenstates. We evidence the transition into the projective regime for a spin oscillator within an ensemble of 2 × 1010 room-temperature atoms by observing correlations between the quadratures of the meter light field. These correlations squeeze the fluctuations of one light quadrature below the vacuum level. When the measurement is slower than the oscillation, we generate 11 . 5 - 1.5 + 2.5 dB and detect 8 . 5 - 0.1 + 0.1 dB of squeezing in a tunable band that is a fraction of the resonance frequency. When the measurement is as fast as the oscillation, we detect 4.7 dB of squeezing that spans more than one decade of frequencies below the resonance. Our results demonstrate a new regime of continuous quantum measurements on material oscillators, and set a new benchmark for the performance of a linear quantum sensor.

2.
Opt Lett ; 49(7): 1761-1764, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38560856

RESUMEN

We present a new, to the best of our knowledge, type of vector three-dimensional dissipative optical solitons with more extended degrees of freedom in a laser or laser medium with saturable absorption. These solitons are reconfigurable, include polarization singularities, and have various mutual orientations of nearly toroidal localization domains of polarization components. Numerical modeling confirms the stability of these solitons and breathers and reveals their symmetry and even "supersymmetry," as well as transformations when parameters leave the stability region. These solitons, which have no scalar analogs, are capable of carrying more than one bit of information. Our results expand the "alphabet" of solitons and can provide a route to breakthroughs in larger-capacity communication and information applications.

3.
Phys Chem Chem Phys ; 26(4): 2870-2876, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38206117

RESUMEN

Bubbles are extensively explored as gas and energy carriers. However, despite notable progress, the bubble transport mechanisms are still poorly understood. At the present time there is not sufficient understanding of whether the body or surface forces play a major role in bubble transport in liquid interfacial systems. This understanding is important to be able to drive oxygen bubble transport. Here, we show the crucial role of solutocapillary forces in oxygen bubble transport in the core of a diffusion-bubbling membrane with a high density of solid/liquid and gas/liquid interfaces that operates under the oxygen chemical potential gradient. In order to describe the transport of oxygen bubbles in the membrane core, we developed a mathematical model. Both the velocity of bubbles and oxygen flux through this membrane predicted by this model agree with experiments. An in-depth understanding of the bubble transport mechanism presented in this study could eventually lead the way to more efficient bubble membrane gas separation, bubble energy generation, and bubble-assisted therapy in the future.

4.
Phys Rev Lett ; 131(6): 060801, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37625068

RESUMEN

Regular measurements allow predicting the future and retrodicting the past of quantum systems. Time-nonlocal measurements can leave the future and the past uncertain, yet establish a relation between them. We show that continuous time-nonlocal measurements can be used to transfer a quantum state via teleportation or direct transmission. Considering two oscillators probed by traveling fields, we analytically identify strategies for performing the state transfer perfectly across a wide range of linear oscillator-field interactions beyond the pure beam-splitter and two-mode-squeezing types.

5.
Materials (Basel) ; 16(6)2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36984419

RESUMEN

Nickel alloy high-speed processing technology using ball-end mills is characterized by high contact temperature and leads to accelerated tool wear. One of the effective ways to increase its reliability and service life is to modify the surface by applying functional antifriction layers in addition to wear-resistant coatings. Diamond-like carbon is often used as the latter. However, at cutting speed, when a cutting-edge temperature exceeding 650 °C is reached, the material of this coating reacts actively with oxygen in the air, and the sharply increasing adhesive component of wear quickly incapacitates the milling tooth, limiting its performance. Applying a coating of titanium diboride as an antifriction layer on top of nanocrystalline composite nitride coatings with good resistance to abrasive wear can be a solution to this problem. Our experiments have shown that such technology makes it possible to obtain a twofold increase in durability compared to a tool with a diamond-like antifriction coating in conditions when the cutting edge of the tool is subjected to cyclic thermal shocks above 800 °C, and the durability period of the radius end mill is about 50 min.

6.
Sensors (Basel) ; 23(2)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36679551

RESUMEN

Creating systems for monitoring technology processes based on concentrated energy flows is an urgent and challenging task for automated production. Similar processes accompany such processing technologies: intensive thermal energy transfer to the substance, heating, development of the melting and evaporation or sublimation, ionization, and expansion of the released substance. It is accompanied by structural and phase rearrangements, local changes in volumes, chemical reactions that cause perturbations of the elastic medium, and the propagation of longitudinal and transverse waves in a wide frequency range. Vibrational energy propagates through the machine's elastic system, making it possible to register vibrations on surfaces remotely. Vibration parameters can be used in monitoring systems to prevent negative phenomena during processing and to be a tool for understanding the processes' kinetics. In some cases, it is the only source of information about the progress in the processing zone.


Asunto(s)
Reproducción , Vibración , Cinética
7.
Med Gas Res ; 13(2): 59-66, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36204784

RESUMEN

Molecular hydrogen (H2) has been considered a preventive and therapeutic medical gas in numerous diseases. The study aimed to investigate the potential role of molecular hydrogen as a component of anesthesia in surgical treatment with cardiopulmonary bypass (CPB) of acquired valve defects on the functional state of red blood cells (RBC) and functional indicators of cardiac activity. This clinical trial was conducted with 20 patients referring to the Specialized Cardiosurgical Clinical Hospital, Nizhny Novgorod, Russian Federation, who underwent elective surgery with CPB. Twenty-four patients were randomly assigned to two groups. First group included 12 patients (research group) who received H2 at a concentration of 1.5-2.0% through a facemask using a breathing circuit of the ventilator together with anesthesia immediately after tracheal intubation and throughout the operation. Second group (control group) included 12 patients who were not given H2. Blood samples were withdrawn from peripheral veins and radial artery at four stages: immediately after the introduction of anesthesia (stage 1), before the start of CPB (stage 2), immediately after its termination (stage 3) and 24 hours after the operation (the early postoperative period) (stage 4). An increase in electrophoretic mobility, an increase in the metabolism of red blood cells, and a decrease in the aggregation of red blood cells relative to the corresponding indicators of the control group were observed in the research group. Patients in the research group had a decrease in oxidative stress manifestations most pronounced one day after the operation. There was a statistically significant difference between the indicators of myocardial contractile function in the research and control group on the 1st and 3rd days after surgery. H2 inhalation leads to improvement of functional state of red blood cells, which is accompanied by a more favorable course of the early postoperative period. These data show the presence of protective properties of molecular hydrogen.


Asunto(s)
Anestesia , Puente Cardiopulmonar , Puente Cardiopulmonar/efectos adversos , Eritrocitos , Humanos , Hidrógeno/uso terapéutico , Periodo Posoperatorio
8.
Mar Drugs ; 20(7)2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35877702

RESUMEN

The cytotoxicity-bioassay-guided fractionation of the ethanol extract from the marine sponge Guitarra abbotti, whose 1-O-alkyl-sn-glycerol ethers (AGEs) have not been investigated so far, led to the isolation of a complex lipid fraction containing, along with previously known compounds, six new lipids of the AGE type. The composition of the AGE fraction as well as the structures of 6 new and 22 previously known compounds were established using 1H and 13C NMR, GC/MS, and chemical conversion methods. The new AGEs were identified as: 1-O-(Z-docos-15-enyl)-sn-glycerol (1), 1-O-(Z-docos-17-enyl)-sn-glycerol (2), 1-O-(Z-tricos-15-enyl)-sn-glycerol (3), 1-O-(Z-tricos-16-enyl)-sn-glycerol (4), 1-O-(Z-tricos-17-enyl)-sn-glycerol (5), and 1-O-(Z-tetracos-15-enyl)-sn-glycerol (6). The isolated AGEs show weak cytotoxic activity in THP-1, HL-60, HeLa, DLD-1, SNU C4, SK-MEL-28, and MDA-MB-231 human cancer cells. A further cytotoxicity analysis in JB6 P+ Cl41 cells bearing mutated MAP kinase genes revealed that ERK2 and JNK1 play a cytoprotective role in the cellular response to the AGE-induced cytotoxic effects.


Asunto(s)
Éteres , Poríferos , Animales , Éteres/farmacología , Cromatografía de Gases y Espectrometría de Masas , Glicerol/farmacología , Éteres de Glicerilo/farmacología , Humanos
9.
Nature ; 607(7918): 313-320, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35768506

RESUMEN

The grey wolf (Canis lupus) was the first species to give rise to a domestic population, and they remained widespread throughout the last Ice Age when many other large mammal species went extinct. Little is known, however, about the history and possible extinction of past wolf populations or when and where the wolf progenitors of the present-day dog lineage (Canis familiaris) lived1-8. Here we analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today. This population connectivity allowed us to detect natural selection across the time series, including rapid fixation of mutations in the gene IFT88 40,000-30,000 years ago. We show that dogs are overall more closely related to ancient wolves from eastern Eurasia than to those from western Eurasia, suggesting a domestication process in the east. However, we also found that dogs in the Near East and Africa derive up to half of their ancestry from a distinct population related to modern southwest Eurasian wolves, reflecting either an independent domestication process or admixture from local wolves. None of the analysed ancient wolf genomes is a direct match for either of these dog ancestries, meaning that the exact progenitor populations remain to be located.


Asunto(s)
Perros , Genoma , Genómica , Filogenia , Lobos , África , Animales , ADN Antiguo/análisis , Perros/genética , Domesticación , Europa (Continente) , Genoma/genética , Historia Antigua , Medio Oriente , Mutación , América del Norte , Selección Genética , Siberia , Proteínas Supresoras de Tumor/genética , Lobos/clasificación , Lobos/genética
10.
J Nat Prod ; 85(4): 1186-1191, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35377646

RESUMEN

Toporosides A-D (1-4), new ω-glycosylated fatty acid amides, were isolated from the sponge Stelodoryx toporoki. The structures of these compounds, including absolute configurations of stereogenic centers, were established using analysis of 1D and 2D NMR, ECD, and HR mass spectra as well as chemical transformations. Toporosides A (1) and B (2) are the first lipids containing a cyclopentenyl α,ß-unsaturated carbonyl moiety in the polymethylene chain. Toporoside C (3) is likely a precursor, which undergoes intramolecular aldol condensation to produce 1 and 2. Toporosides A, C, and D showed protective effects against TNF-α-induced injury in H9c2 cardiomyocytes.


Asunto(s)
Amidas , Poríferos , Amidas/química , Animales , Ácidos Grasos/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Poríferos/química
11.
Opt Lett ; 47(23): 6257-6260, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37219221

RESUMEN

We analyze the effect of frequency locking for polarization components of a semiconductor laser with fast gain, saturating absorption, and weak anisotropy. A mode of alternation of topological indices when leaving the locking area was found.

12.
Phys Chem Chem Phys ; 23(41): 24029-24038, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34664561

RESUMEN

Oxygen-selective membranes are likely to play a leading part in the future separation processes relevant to energy engineering. A newly developed molten copper and vanadium oxide-based diffusion-bubbling membrane with core-shell structure and fast combined oxygen mass transfer is a promising candidate for efficient oxygen separation. In this work, the oxygen bubble nucleation and transport properties of the diffusion-bubbling membrane were experimentally and theoretically studied. Bubble size distribution and cumulative oxygen flux have been plotted as functions of oxygen partial pressure. The relationship between the bubble density, oxygen partial pressure, and oxygen permeation flux was established. The oxygen flux and bubble density vary in the ranges of 3.2 × 10-8-1.4 × 10-7 mol cm-2 s-1 and 1.3 × 1013-5.8 × 1013 m-3 at ΔPO2 = 0.1-0.75 atm, respectively. The mechanisms of homogeneous, heterogeneous, pseudo-classical and non-classical nucleation are reviewed within the framework of the Cahn-Hilliard model. It is shown that the homogeneous nucleation mechanism is most likely in the membrane core. The estimated values of the interfacial tension, energy barrier, and rate nucleation are 0.02 J m-2, 5 kT, and 4 × 1029 m-3 s-1, respectively.

13.
Opt Lett ; 46(16): 4076-4079, 2021 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-34388815

RESUMEN

We analyze, to the best of our knowledge, a new type of topological optical solitons in lasers with fast saturable absorption, which is intermediate between 2D and 3D ones. Being generated by 2D laser solitons, such 3D dissipative solitons in a laser cavity of length L have a number of vortex lines, which are straight for under-critical values L and spiral for larger L. For supercritical L, a vortex with multiple topological charges m>1 in generating 2D solitons transforms into m separate vortex lines. Taking into account weak non-paraxiality reveals polarization singularities in the form of lines, on which the elliptical polarization turns into linear in the cross section of the structures.

14.
Materials (Basel) ; 14(12)2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34207860

RESUMEN

The mechanism of the material destruction under discharge pulses and material removal mechanism based on the thermochemical nature of the electrical erosion during electrical discharge machining of conductive materials were researched. The experiments were conducted for two structural materials used in the aerospace industry, namely austenite anticorrosion X10CrNiTi18-10 (12kH18N10T) steel and 2024 (D16) duralumin, machined by a brass tool of 0.25 mm in diameter in a deionized water medium. The optimized wire electrical discharge machining factors, measured discharge gaps (recommended offset is 170-175 µm and 195-199 µm, respectively), X-ray photoelectron spectroscopy for both types of materials are reported. Elemental analysis showed the presence of metallic Zn, CuO, iron oxides, chromium oxides, and 58.07% carbides (precipitation and normal atmospheric contamination) for steel and the presence of metallic Zn, CuO, ZnO, aluminum oxide, and 40.37% carbides (contamination) for duralumin. For the first time, calculating the thermochemistry parameters for reactions of Zn(OH)2, ZnO, and NiO formation was produced. The ability of Ni of chrome-nickel steel to interact with Zn of brass electrode was thermochemically proved. The standard enthalpy of the Ni5Zn21 intermetallic compound formation (erosion dust) ΔH0298 is -225.96 kJ/mol; the entropy of the crystalline phase Scint is 424.64 J/(mol·K).

15.
Langmuir ; 37(28): 8370-8381, 2021 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-34236866

RESUMEN

Oxygen is the second-largest-volume industrial gas that is mainly produced using cryogenic air separation. However, the state-of-the-art cryogenic technology thermodynamic efficiency has approached a theoretical limit as near as is practicable. Therefore, there is stimulus to develop an alternative technology for efficient oxygen separation from air. Mixed ionic electronic-conducting (MIEC) ceramic membrane-based oxygen separation technology could become this alternative, but commercialization aspects, including cost, have revealed inadequacies in ceramic membrane materials. Currently, diffusion-bubbling molten oxide membrane-based oxygen separation technology is being developed. It is a potentially disruptive technology that would propose an improvement in oxygen purity and a reduction in capital costs. Bubbles play an important role in ensuring the oxygen mass transfer in diffusion-bubbling membranes. However, there is not sufficient understanding of the bubble dynamics. This understanding is important to be able to control transport properties of these membranes and assess their potential for technological application. The aim of this feature article is to highlight the progress made in developing this understanding and specify the directions for future research.

16.
Curr Biol ; 31(1): 198-206.e8, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33125870

RESUMEN

Extant Canis lupus genetic diversity can be grouped into three phylogenetically distinct clades: Eurasian and American wolves and domestic dogs.1 Genetic studies have suggested these groups trace their origins to a wolf population that expanded during the last glacial maximum (LGM)1-3 and replaced local wolf populations.4 Moreover, ancient genomes from the Yana basin and the Taimyr peninsula provided evidence of at least one extinct wolf lineage that dwelled in Siberia during the Pleistocene.35 Previous studies have suggested that Pleistocene Siberian canids can be classified into two groups based on cranial morphology. Wolves in the first group are most similar to present-day populations, although those in the second group possess intermediate features between dogs and wolves.67 However, whether this morphological classification represents distinct genetic groups remains unknown. To investigate this question and the relationships between Pleistocene canids, present-day wolves, and dogs, we resequenced the genomes of four Pleistocene canids from Northeast Siberia dated between >50 and 14 ka old, including samples from the two morphological categories. We found these specimens cluster with the two previously sequenced Pleistocene wolves, which are genetically more similar to Eurasian wolves. Our results show that, though the four specimens represent extinct wolf lineages, they do not form a monophyletic group. Instead, each Pleistocene Siberian canid branched off the lineage that gave rise to present-day wolves and dogs. Finally, our results suggest the two previously described morphological groups could represent independent lineages similarly related to present-day wolves and dogs.


Asunto(s)
ADN Antiguo , Perros/genética , Genoma , Lobos/genética , Animales , Biodiversidad , ADN Mitocondrial/genética , Perros/anatomía & histología , Extinción Biológica , Asia Oriental , Fósiles , Geografía , Filogenia , Siberia , Cráneo/anatomía & histología , Lobos/anatomía & histología
17.
Science ; 370(6516): 557-564, 2020 10 30.
Artículo en Inglés | MEDLINE | ID: mdl-33122379

RESUMEN

Dogs were the first domestic animal, but little is known about their population history and to what extent it was linked to humans. We sequenced 27 ancient dog genomes and found that all dogs share a common ancestry distinct from present-day wolves, with limited gene flow from wolves since domestication but substantial dog-to-wolf gene flow. By 11,000 years ago, at least five major ancestry lineages had diversified, demonstrating a deep genetic history of dogs during the Paleolithic. Coanalysis with human genomes reveals aspects of dog population history that mirror humans, including Levant-related ancestry in Africa and early agricultural Europe. Other aspects differ, including the impacts of steppe pastoralist expansions in West and East Eurasia and a near-complete turnover of Neolithic European dog ancestry.


Asunto(s)
Animales Domésticos/genética , Perros/genética , Lobos/genética , África , Animales , Domesticación , Europa (Continente) , Genómica , Población
18.
Curr Biol ; 30(19): 3871-3879.e7, 2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-32795436

RESUMEN

Ancient DNA has significantly improved our understanding of the evolution and population history of extinct megafauna. However, few studies have used complete ancient genomes to examine species responses to climate change prior to extinction. The woolly rhinoceros (Coelodonta antiquitatis) was a cold-adapted megaherbivore widely distributed across northern Eurasia during the Late Pleistocene and became extinct approximately 14 thousand years before present (ka BP). While humans and climate change have been proposed as potential causes of extinction [1-3], knowledge is limited on how the woolly rhinoceros was impacted by human arrival and climatic fluctuations [2]. Here, we use one complete nuclear genome and 14 mitogenomes to investigate the demographic history of woolly rhinoceros leading up to its extinction. Unlike other northern megafauna, the effective population size of woolly rhinoceros likely increased at 29.7 ka BP and subsequently remained stable until close to the species' extinction. Analysis of the nuclear genome from a ∼18.5-ka-old specimen did not indicate any increased inbreeding or reduced genetic diversity, suggesting that the population size remained steady for more than 13 ka following the arrival of humans [4]. The population contraction leading to extinction of the woolly rhinoceros may have thus been sudden and mostly driven by rapid warming in the Bølling-Allerød interstadial. Furthermore, we identify woolly rhinoceros-specific adaptations to arctic climate, similar to those of the woolly mammoth. This study highlights how species respond differently to climatic fluctuations and further illustrates the potential of palaeogenomics to study the evolutionary history of extinct species.


Asunto(s)
Arqueología/métodos , ADN Antiguo/análisis , Perisodáctilos/genética , Animales , Cambio Climático , Extinción Biológica , Fósiles , Genoma/genética , Genómica/métodos , Densidad de Población , Dinámica Poblacional
19.
Sci Rep ; 10(1): 12621, 2020 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-32724178

RESUMEN

The cave lion is an extinct felid that was widespread across the Holarctic throughout the Late Pleistocene. Its closest extant relative is the lion (Panthera leo), but the timing of the divergence between these two taxa, as well as their taxonomic ranking are contentious. In this study we analyse 31 mitochondrial genome sequences from cave lion individuals that, through a combination of 14C and genetic tip dating, are estimated to be from dates extending well into the mid-Pleistocene. We identified two deeply diverged and well-supported reciprocally monophyletic mitogenome clades in the cave lion, and an additional third distinct lineage represented by a single individual. One of these clades was restricted to Beringia while the other was prevalent across western Eurasia. These observed clade distributions are in line with previous observations that Beringian and European cave lions were morphologically distinct. The divergence dates for these lineages are estimated to be far older than those between extant lions subspecies. By combining our radiocarbon tip-dates with a split time prior that takes into account the most up-to-date fossil stem calibrations, we estimated the mitochondrial DNA divergence between cave lions and lions to be 1.85 Million ya (95% 0.52- 2.91 Mya). Taken together, these results support previous hypotheses that cave lions existed as at least two subspecies during the Pleistocene, and that lions and cave lions were distinct species.


Asunto(s)
Biodiversidad , Cuevas , Leones/genética , Animales , Genoma Mitocondrial , Geografía , Filogenia , Especificidad de la Especie , Manejo de Especímenes , Factores de Tiempo
20.
Sci Rep ; 10(1): 9764, 2020 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-32555282

RESUMEN

New bicyclic guanidine alkaloid, urupocidin C (Ur-C) along with the previously known urupocidin A (Ur-A) were isolated from the rare deep-sea marine sponge Monanchora pulchra, harvested in Northwestern Pacific waters. The unique structure of Ur-C was elucidated using 1D and 2D NMR spectroscopy as well as mass spectra. We discovered a promising selectivity of both alkaloids for human prostate cancer (PCa) cells, including highly drug-resistant lines, compared to non-malignant cells. In cancer cells, marine derived compounds were able to induce G1- and S-cell cycle arrest as well as caspase-mediated cell death. For the first time we have identified mitochondrial targeting as a central mechanism of anticancer action for these and similar molecules. Thus, treatment with the isolated alkaloids resulted in mitochondrial membrane permeabilization consequently leading to the release of cytotoxic mitochondrial proteins to cellular cytoplasm, ROS upregulation, consequent activation of caspase-9 and -3, followed by PARP cleavage, DNA fragmentation, and apoptosis. Moreover, synergistic effects were observed when Ur-A and Ur-C were combined with clinically approved PARP inhibitor olaparib. Finally, these alkaloids exhibited additive effects in combination with docetaxel and androgen receptor inhibitor enzalutamide, both applied in PCa therapy. In conclusion, urupocidin-like compounds are promising lead molecules for the development of new drugs for the treatment of advanced PCa.


Asunto(s)
Alcaloides/farmacología , Antineoplásicos/farmacología , Apoptosis , Guanidinas/farmacología , Mitocondrias/efectos de los fármacos , Poríferos/química , Neoplasias de la Próstata/patología , Animales , Puntos de Control del Ciclo Celular , Muerte Celular , Masculino , Mitocondrias/patología , Neoplasias de la Próstata/tratamiento farmacológico , Células Tumorales Cultivadas
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