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101.
Maxim A. Scott B. Schneider E.M. Hagge M.L. Chacko S. Stiurca D. 《Solid-State Circuits, IEEE Journal of》2001,36(11):1673-1683
This paper describes a low-jitter phase-locked loop (PLL) implemented in a 0.18-μm CMOS process. A sample-reset loop filter architecture is used that averages the oscillator proportional control current which provides the feedforward zero over an entire update period and hence leads to a ripple-free control signal. The ripple-free control current eliminates the need for an additional filtering pole, leading to a nearly 90° phase margin which minimizes input jitter peaking and transient locking overshoot. The PLL damping factor is made insensitive to process variations by making it dependent only upon a bandgap voltage and ratios of circuit elements. This ensures tracking between the natural frequency and the stabilizing zero. The PLL has a frequency range of 125-1250 MHz, frequency resolution better than 500 kHz, and rms jitter less than 0.9% of the oscillator period 相似文献
102.
Alexander Kostyunin Tatiana Glushkova Alexander Stasev Rinat Mukhamadiyarov Elena Velikanova Leo Bogdanov Anna Sinitskaya Maxim Asanov Evgeny Ovcharenko Leonid Barbarash Anton Kutikhin 《International journal of molecular sciences》2022,23(12)
A 72-year-old female patient with mixed rheumatic mitral valve disease and persistent atrial fibrillation underwent mitral valve replacement and suffered from a combined thrombosis of the bioprosthetic valve and the left atrium as soon as 2 days post operation. The patient immediately underwent repeated valve replacement and left atrial thrombectomy. Yet, four days later the patient died due to the recurrent prosthetic valve and left atrial thrombosis which both resulted in an extremely low cardiac output. In this patient’s case, the thrombosis was notable for the resistance to anticoagulant therapy as well as for aggressive neutrophil infiltration and release of neutrophil extracellular traps (NETs) within the clot, as demonstrated by immunostaining. The reasons behind these phenomena remained unclear, as no signs of sepsis or contamination of the BHV were documented, although the patient was diagnosed with inherited thrombophilia that could impede the fibrinolysis. The described case highlights the hazard of immunothrombosis upon valve replacement and elucidates its mechanisms in this surgical setting. 相似文献
103.
Vadim E. Filatov Dmitrii A. Iuzabchuk Viktor A. Tafeenko Yuri K. Grishin Vitaly A. Roznyatovsky Dmitrii A. Lukianov Yulia A. Fedotova Maxim A. Sukonnikov Dmitry A. Skvortsov Nikolai V. Zyk Elena K. Beloglazkina 《International journal of molecular sciences》2022,23(12)
In this work, we present the first synthesis of dispirooxindole-β-lactams employing optimized methodology of one-pot Staudinger ketene-imine cycloaddition with N-aryl-2-oxo-pyrrolidine-3-carboxylic acids as the ketene source. Spiroconjugation of indoline-2-one with β-lactams ring is considered to be able to provide stabilization and wide scope of functionalization to resulting scaffolds. The dispipooxindoles obtained demonstrated medium cytotoxicity in the MTT test on A549, MCF7, HEK293, and VA13 cell lines, and one of the compounds demonstrated antibacterial activity against E. coli strain LPTD. 相似文献
104.
105.
Tao Hu Lixin Ning Yan Gao Jianwei Qiao Enhai Song Zitao Chen Yayun Zhou Jing Wang Maxim S.Molokeev Xiaoxing Ke Zhiguo Xia Qinyuan Zhang 《光:科学与应用(英文版)》2021,10(4):570-581
Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence, and especially relies on blue light p... 相似文献
106.
Olga Porembskaya Vsevolod Zinserling Vladimir Tomson Yana Toropova Eleonora A. Starikova Vitaliy V. Maslei Nika I. Bulavinova Olga V. Kirik Marina A. Syrtsova Leonid Laberko Maxim I. Galchenko Vyacheslav Kravchuk Sergey Saiganov Alexander Brill 《International journal of molecular sciences》2022,23(10)
Pulmonary embolism is a life-threatening condition, which can result in respiratory insufficiency and death. Blood clots occluding branches of the pulmonary artery (PA) are traditionally considered to originate from thrombi in deep veins (usually in legs). However, growing evidence suggests that occlusion of the vessels in the lungs can develop without preceding deep vein thrombosis (DVT). In this work, we used an inferior vena cava (IVC) complete ligation model of DVT in Wistar rats to explore the possibility and mechanisms of PA thrombosis under the conditions where all routes of thrombotic mass migration from peripheral veins are blocked. We demonstrate that rats both with normal and reduced neutrophil counts developed thrombi in the IVC, although, neutropenia caused a substantial decrease in thrombus size and a shift from fresh fibrin toward mature fibrin and connective tissue inside the thrombus. Massive fibrin deposition was found in the PA branches in the majority of DVT rats with normal neutrophil counts, but in none of the neutropenic animals. Neutrophil ablation also abolished macroscopic signs of lung damage. Altogether, the results demonstrate that thrombi in the lung vasculature can form in situ by mechanisms that require local neutrophil recruitment taking place in the DVT setting. 相似文献
107.
Marianna A. Zolotovskaia Max A. Kovalenko Victor S. Tkachev Alexander M. Simonov Maxim I. Sorokin Ella Kim Denis V. Kuzmin Betul Karademir-Yilmaz Anton A. Buzdin 《International journal of molecular sciences》2022,23(13)
In gliomas, expression of certain marker genes is strongly associated with survival and tumor type and often exceeds histological assessments. Using a human interactome model, we algorithmically reconstructed 7494 new-type molecular pathways that are centered each on an individual protein. Each single-gene expression and gene-centric pathway activation was tested as a survival and tumor grade biomarker in gliomas and their diagnostic subgroups (IDH mutant or wild type, IDH mutant with 1p/19q co-deletion, MGMT promoter methylated or unmethylated), including the three major molecular subtypes of glioblastoma (proneural, mesenchymal, classical). We used three datasets from The Cancer Genome Atlas and the Chinese Glioma Genome Atlas, which in total include 527 glioblastoma and 1097 low grade glioma profiles. We identified 2724 such gene and 2418 pathway survival biomarkers out of total 17,717 genes and 7494 pathways analyzed. We then assessed tumor grade and molecular subtype biomarkers and with the threshold of AUC > 0.7 identified 1322/982 gene biomarkers and 472/537 pathway biomarkers. This suggests roughly two times greater efficacy of the reconstructed pathway approach compared to gene biomarkers. Thus, we conclude that activation levels of algorithmically reconstructed gene-centric pathways are a potent class of new-generation diagnostic and prognostic biomarkers for gliomas. 相似文献
108.
DIDS: rapidly prototyping configuration design systems 总被引:3,自引:0,他引:3
Alan Balkany William P. Birmingham Bruce Maxim Jay T. Runkel Iris D. Tommelein 《Journal of Intelligent Manufacturing》1994,5(1):33-45
The domain independent design system (DIDS) provides a set of tools for rapidly constructing new configuration design systems from a library of reusable software elements called mechanisms. A DIDS user begins by creating a model of the problem domain and the task to be automated. This includes describing a library of parts from which new artifacts could be configured, optimization and preference criteria, and functionality constraints. DIDS analyzes this input and automatically builds an operational prototype system by selecting and combining mechanisms. DIDS' ability to automate this process is derived from its model of configuration design, which enables reusable mechanisms to be identified and automatically selected based on a problem's characteristics. The use of DIDS is illustrated by showing how DIDS solved an elevator-configuration problem. 相似文献
109.
Anatolii S. Burlov Valery G. Vlasenko Maxim S. Milutka Yurii V. Koshchienko Nadezhda I. Makarova Vladimir A. Lazarenko Alexander L. Trigub Alexandra A. Kolodina Alexander A. Zubenko Anatoly V. Metelitsa Dmitrii A. Garnovskii Alexey N. Gusev Wolfgang Linert 《International journal of molecular sciences》2022,23(23)
New azomethine compounds of 2-(N-tosylamino)benzaldehyde or 5-chloro-2-(N-tosylamino)benzaldehyde and the corresponding chlorine-substituted anilines, zinc(II) complexes based on them have been synthesized. The structures of azomethines and their complexes were determined by elemental analysis, IR, 1H NMR, X-ray spectroscopy, and X-ray diffraction. It is found that all ZnL2 complexes have a tetrahedral structure according to XAFS and X-ray diffraction data. The photoluminescent properties of azomethines and zinc complexes in methylene chloride solution and in solid form have been studied. It is shown that the photoluminescence quantum yields of solid samples of the complexes are an order of magnitude higher compared to the solutions and range from 11.34% to 48.3%. The thermal properties of Zn(II) complexes were determined by thermal gravimetric analysis (TGA) and differential scanning calorimetry. The TGA curves of all the compounds suggest their high thermal stability up to temperatures higher than 290 °C. The electrochemical properties of all complexes were investigated by the cyclic voltammetry method. The multilayered devices ITO/PEDOT:PSS/NPD/Zn complex/ TPBI/LiF/Al with wide electroluminescence (EL) color range spanning the range from bluish-green (494 nm) to green (533 nm) and the high values of brightness, current and power efficiency were fabricated. The biological activity of azomethines and zinc complexes has been studied. In the case of complexes, the protistocidal activity of the zinc complex with azomethine of 5-chloro-2-(N-tosylamino)benzaldehyde with 4-chloroaniline was two times higher than the activity of the reference drug toltrazuril. 相似文献
110.
Polina Drozdova Alexandra Saranchina Ekaterina Madyarova Anton Gurkov Maxim Timofeyev 《International journal of molecular sciences》2022,23(18)
Ancient lakes are known speciation hotspots. One of the most speciose groups in the ancient Lake Baikal are gammaroid amphipods (Crustacea: Amphipoda: Gammaroidea). There are over 350 morphological species and subspecies of amphipods in Baikal, but the extent of cryptic variation is still unclear. One of the most common species in the littoral zone of the lake, Eulimnogammarus verrucosus (Gerstfeldt, 1858), was recently found to comprise at least three (pseudo)cryptic species based on molecular data. Here, we further explored these species by analyzing their mitogenome-based phylogeny, genome sizes with flow cytometry, and their reproductive compatibility. We found divergent times of millions of years and different genome sizes in the three species (6.1, 6.9 and 8 pg), further confirming their genetic separation. Experimental crossing of the western and southern species, which are morphologically indistinguishable and have adjacent ranges, showed their separation with a post-zygotic reproductive barrier, as hybrid embryos stopped developing roughly at the onset of gastrulation. Thus, the previously applied barcoding approach effectively indicated the separate biological species within E. verrucosus. These results provide new data for investigating genome evolution and highlight the need for precise tracking of the sample origin in any studies in this morphospecies. 相似文献