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1.
Nature ; 589(7840): 52-58, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408373

RESUMEN

With the proliferation of ultrahigh-speed mobile networks and internet-connected devices, along with the rise of artificial intelligence (AI)1, the world is generating exponentially increasing amounts of data that need to be processed in a fast and efficient way. Highly parallelized, fast and scalable hardware is therefore becoming progressively more important2. Here we demonstrate a computationally specific integrated photonic hardware accelerator (tensor core) that is capable of operating at speeds of trillions of multiply-accumulate operations per second (1012 MAC operations per second or tera-MACs per second). The tensor core can be considered as the optical analogue of an application-specific integrated circuit (ASIC). It achieves parallelized photonic in-memory computing using phase-change-material memory arrays and photonic chip-based optical frequency combs (soliton microcombs3). The computation is reduced to measuring the optical transmission of reconfigurable and non-resonant passive components and can operate at a bandwidth exceeding 14 gigahertz, limited only by the speed of the modulators and photodetectors. Given recent advances in hybrid integration of soliton microcombs at microwave line rates3-5, ultralow-loss silicon nitride waveguides6,7, and high-speed on-chip detectors and modulators, our approach provides a path towards full complementary metal-oxide-semiconductor (CMOS) wafer-scale integration of the photonic tensor core. Although we focus on convolutional processing, more generally our results indicate the potential of integrated photonics for parallel, fast, and efficient computational hardware in data-heavy AI applications such as autonomous driving, live video processing, and next-generation cloud computing services.

2.
Bull Exp Biol Med ; 174(3): 395-398, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36723750

RESUMEN

In adult Wistar rats, post-toxic liver cirrhosis was induced by intraperitoneal injection of 50% oil solution of CCl4 and peroral administration of 6.5% aqueous solution of ethyl alcohol over 60 days. Histological examination of the liver revealed vacuolar degeneration and necrosis of hepatocytes, formation of false lobules, expression of collagens I and III periportally and in interlobular spaces, ascites, and hydrothorax. Then, oxidized dextran with a molecular weight of 40 kDa (2 ml of a 5% aqueous solution) was intraperitoneally injected every fourth day over 30 days. Against the background of treatment with oxidized dextran, the volume density of collagens I and III decreased by more than 2 times, the "collagen-producing" activity of fibroblasts decreased by 47%, and the number of fibroblasts decreased, including by the mechanism of apoptosis. The decrease in the collagen content in the liver of rats treated with oxidized dextran was apparently associated with blockade of collagen assembly due to the aldehyde-aldehyde interaction of tropocollagens and oxidized dextran.


Asunto(s)
Dextranos , Hígado , Ratas , Animales , Dextranos/metabolismo , Ratas Wistar , Hígado/metabolismo , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Colágeno/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Tetracloruro de Carbono/toxicidad
3.
Arkh Patol ; 85(3): 71-74, 2023.
Artículo en Ruso | MEDLINE | ID: mdl-37272443

RESUMEN

Chronic gastric ulcer is a rare disease in childhood. The article presents data on the epidemiology and etiology of the disease in children, describes the case of a chronic gastric ulcer complicated by penetration into the liver, perforation, development of abdominal sepsis, with a fatal outcome in a 7-year-old girl.


Asunto(s)
Úlcera Gástrica , Femenino , Humanos , Niño , Úlcera Gástrica/diagnóstico , Úlcera Gástrica/complicaciones , Hígado
5.
Bull Exp Biol Med ; 171(4): 416-420, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34542744

RESUMEN

Adhesions in rat abdominal cavity were studied after laparotomy and subsequent single intraperitoneal injection of 2 ml of 5% aqueous solution of oxidized dextran (OD) with a molecular weight of 40 kDa (oxidation degree 10%). On days 7 and 21 after laparotomy, the number of adhesions in OD-treated rats was lower by 7.5 and 4 times than in animals not receiving OD. The number of neutrophils in adhesions on day 21 was manyfold lower in OD-treated rats. In 7 and 21 days after laparotomy, the number of fibroblasts in the adhesions of rats receiving and not receiving OD was similar, but 2-fold higher than in the peritoneum of non-operated rats. The content of collagen in adhesions on day 21 after laparotomy in OD-treated rats was 10-fold lower than in animals no receiving OD.


Asunto(s)
Dextranos/farmacología , Laparotomía/efectos adversos , Complicaciones Posoperatorias/prevención & control , Adherencias Tisulares/prevención & control , Cavidad Abdominal/patología , Cavidad Abdominal/cirugía , Animales , Dextranos/administración & dosificación , Modelos Animales de Enfermedad , Inyecciones Intraperitoneales , Masculino , Peritoneo/efectos de los fármacos , Peritoneo/patología , Ratas , Ratas Wistar , Resultado del Tratamiento
6.
Arkh Patol ; 80(2): 7-10, 2018.
Artículo en Ruso | MEDLINE | ID: mdl-29697665

RESUMEN

Perinatal mortality rate is an indicator that characterizes the quality of medical care, as well as the social and economic situation in the region. OBJECTIVE: to audit perinatal losses in large regional centers of the Russian Federation with a population of over 1 million inhabitants, such as Chelyabinsk and Novosibirsk. MATERIAL AND METHODS: A comprehensive postmortem examination of 309 cases of perinatal losses in 2016 was made, which was supplemented with an assessment of preventability according to the Scandinavian-Baltic classification. RESULTS: The rate of preventable deaths in Chelyabinsk and Novosibirsk amounted to 91 and 81.5% of cases, respectively; the deaths were due to stillbirths at more than 28 weeks' gestation and to dead newborns in almost half of cases. The proportion of intranatal deaths was shown to increase in Chelyabinsk; the number of neonatal deaths at more than 33 weeks' gestation rose in Novosibirsk. CONCLUSION: Supplementing the traditional clinical and postmortem analysis with an assessment of the preventability of perinatal loss makes it possible to ensure a unified approach to evaluating these conditions and the comparability of autopsy results in different subjects of the Russian Federation and to determine regional reserves for reducing perinatal mortality rates.


Asunto(s)
Mortalidad Infantil , Mortalidad Perinatal , Mortinato , Ciudades , Femenino , Humanos , Lactante , Mortalidad Infantil/tendencias , Recién Nacido , Mortalidad Perinatal/tendencias , Embarazo , Federación de Rusia/epidemiología
7.
Opt Lett ; 42(3): 514-517, 2017 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28146515

RESUMEN

We present a novel compact dual-comb source based on a monolithic optical crystalline MgF2 multi-resonator stack. The coherent soliton combs generated in the two microresonators of the stack with the repetition rate of 12.1 GHz and difference of 1.62 MHz provided after heterodyning a 300 MHz wide radio frequency comb. An analogous system can be used for dual-comb spectroscopy, coherent LIDAR applications, and massively parallel optical communications.

8.
Bull Exp Biol Med ; 159(3): 398-401, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26212815

RESUMEN

The effects of nanosized particles (4-6 nm) of synthetic diamonds on mouse macrophage expression and secretion of lysosomal cathepsins (B and D) and MMP-1 and MMP-9 were studied in vitro. Culturing of peritoneal macrophages in medium with diamond nanoparticles led to an increase in the counts of macrophages expressing the above enzymes and to stimulation of their secretion. However, the manifestations of these effects varied significantly for various enzymes. The data indicate modulation of macrophage functions by nanodiamonds. These results help better understand the possible role of the "corpuscular" xenobiotic factors in the pathogenesis of diseases associated with macrophage capturing of these factors irrespective of their chemical "activity".


Asunto(s)
Diamante/química , Macrófagos/metabolismo , Nanopartículas/química , Animales , Catepsinas/metabolismo , Hidrólisis , Macrófagos/efectos de los fármacos , Masculino , Metaloproteasas/metabolismo , Ratones , Ratones Endogámicos BALB C
9.
Bull Exp Biol Med ; 158(5): 628-31, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25778648

RESUMEN

Grade IIIB skin burns were treated with a composition based on oxidized dextran with a molecular weight of 40 kDa (oxidation of 7% glucose residues). On day 32 after burn infliction and from the start of the treatment, the area of skin defect in rats was 30% less than in the group without treatment and by 2.3 times less than in rats treated with panthenol. In rats treated with dextran-based composition or panthenol, the eschar was absent on day 21 after the start of the treatment; by day 32, we found cells of surface epithelium, hair follicles, and sebaceous glands above the scar tissue that were absent in untreated animals; in rats treated with the composition, their number was higher by 2.5 times than in animals treated with panthenol. Treatment with the composition increased volume density (by 2.5 times) and numerical density (by more than 3 times) of blood vessels in the wound and reduced signs of inflammation and fibroplastic activity of fibroblasts in comparison with the corresponding parameters in untreated animals or animals treated with panthenol.


Asunto(s)
Quemaduras/tratamiento farmacológico , Dextranos/química , Dextranos/uso terapéutico , Piel/lesiones , Animales , Macrófagos/metabolismo , Masculino , Neutrófilos/metabolismo , Ratas , Ratas Wistar , Piel/efectos de los fármacos
10.
Sud Med Ekspert ; 58(6): 44-45, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26856060

RESUMEN

This article reports the case of death of a puerperal woman resulting from amniotic fluid embolism. The diagnosis was established based on the results of the pathohistological study that revealed the presence of mucoproteides and epithelial scales in pulmonary blood vessels and capillaries.


Asunto(s)
Embolia de Líquido Amniótico , Adulto , Embolia de Líquido Amniótico/diagnóstico , Embolia de Líquido Amniótico/etiología , Embolia de Líquido Amniótico/fisiopatología , Embolia de Líquido Amniótico/terapia , Femenino , Patologia Forense/métodos , Humanos , Muerte Materna , Embarazo , Resucitación/métodos
11.
Arkh Patol ; 76(3): 33-6, 2014.
Artículo en Ruso | MEDLINE | ID: mdl-25306608

RESUMEN

OBJECTIVE: To study placental morphological changes in inherited thrombophilia. SUBJECT AND METHODS: A morphometric method was used to examine placentas from 37 patients divided into 3 groups: 1) 13 pregnant women with verified inherited thrombophilia; 2) 14 pregnant women with inherited thrombophilia and signs of placental inflammatory manifestations (basal deciduitis, intervillositis, placentitis); 3) 10 women with normal pregnancy (a control group). RESULTS: In inherited thrombophilia, the placentas exhibited morphological manifestations of chronic placental insufficiency as pathological immaturity with a predominance of intermediate differentiated villi and as dissociated maturity of cotyledones, with a substantial reduction in the specialized terminal villi, excessive intervillous fibrinoid formation and villous immuring, evolving pseudoinfarctions, fewer capillaries in the terminal villi, and their increased stromal proportion. At the same time, no significant differences were found in the morphological pattern in inherited thrombophilia concurrent with placental inflammatory changes. CONCLUSION: In inherited thrombophilia, there is chronic placental insufficiency caused by delayed development of the shaggy chorion.


Asunto(s)
Placenta/patología , Insuficiencia Placentaria/patología , Complicaciones Hematológicas del Embarazo/patología , Trombofilia/patología , Adulto , Vellosidades Coriónicas/patología , Femenino , Humanos , Embarazo , Complicaciones del Embarazo/patología
12.
Bull Exp Biol Med ; 153(5): 647-50, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23113247

RESUMEN

In adult Wistar rats, a 3B degree skin burn was modeled and treated by daily application of 5% aqueous solution of oxidized dextran (molecular weight of 60 kDa) on the wound surface. In animals treated with oxidized dextran, neutrophil count in the connective tissue adjacent to the wound increased by day 5 and then decreased by day 21 after burn infliction; proliferation of fibroblasts was observed later than in untreated animals, in whom inflammation run a subacute course. Oxidized dextran increased the content of macrophages in the wound and surrounding connective tissue from days 14 to 21 after burn infliction and promoted effective and complete healing of the skin defect. Regeneration was realized mainly due to proliferation of keratinocytes at the wound edges and was completed by 7 days earlier than in untreated animals, in whom the area of injury by day 21 decreased by only 2 times (vs. 10 times in treated rats).


Asunto(s)
Quemaduras/tratamiento farmacológico , Dextranos/farmacología , Regeneración/efectos de los fármacos , Fenómenos Fisiológicos de la Piel/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Animales , Recuento de Células , Proliferación Celular/efectos de los fármacos , Queratinocitos/fisiología , Macrófagos/efectos de los fármacos , Masculino , Activación Neutrófila/efectos de los fármacos , Ratas , Ratas Wistar
13.
Sci Rep ; 11(1): 7682, 2021 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-33833349

RESUMEN

The development of new methods for generating pulsed electromagnetic microwave radiation is currently an actively developing area of research. Schemes for microwave radiation generation with optical pumping are of great interest. In this paper we propose and experimentally demonstrate principally new method for photonic generation of microwave electromagnetic radiation. This method is based on the use of radiation of charged submicron particles oscillating at their own acoustic frequency. Laser radiation of the optical range implements an effective buildup of acoustic vibrations of submicron particles forming the system under study, according to the Raman mechanism.

14.
Bull Exp Biol Med ; 149(5): 659-62, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21165412

RESUMEN

The stimulating effect of silicon dioxide on fibroblast proliferation in granulomas of male CBA mice surpasses that of BCG vaccine mycobacteria. The number of fibroblasts in granulomas after combined treatment with BCG and SiO2 increased by more than 3 times compared to individual treatment with BCG and by 2 times compared to treatment with SiO2 alone. In silicosis and silicotuberculosis, collagen and argyrophilic fibers in granulomas during the period from 4 to 6 months after administration of granulomogenic factors occupied more than 90% granuloma volume, which 3-fold surpassed the corresponding parameter in mice infected with BCG vaccine alone. In silicosis, pronounced fibrosis was determined by relatively high proliferative and synthetic activities of fibroblasts, while in silicotuberculosis it was achieved due to significantly higher proliferative activity against the background of lower synthetic activity.


Asunto(s)
Granuloma/patología , Silicosis/patología , Silicotuberculosis/patología , Animales , Vacuna BCG , Colágeno/metabolismo , Fibroblastos/patología , Fibrosis , Granuloma/inducido químicamente , Hígado/patología , Masculino , Ratones , Ratones Endogámicos CBA , Dióxido de Silicio
15.
Bull Exp Biol Med ; 149(6): 685-8, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21165418

RESUMEN

Experimental silicosis and silicotuberculosis induced by intravenous injection of silicon dioxide particles are characterized by extensive degenerative and necrotic processes in the liver parenchyma. After 6 months, fibrosis of portal tracts in silicotuberculosis and silicosis was 2.8- and 1.4-fold more pronounced that in BCG granulomatosis and silicosis, respectively. Depression of cellular and intracellular regeneration processes in the liver parenchyma was also observed.


Asunto(s)
Granuloma/etiología , Hígado/patología , Silicosis/patología , Tuberculosis/patología , Animales , Enfermedad Crónica , Masculino , Ratones , Ratones Endogámicos CBA , Silicosis/complicaciones , Tuberculosis/complicaciones
16.
Bull Exp Biol Med ; 149(4): 462-5, 2010 Oct.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-21234444

RESUMEN

Silicon dioxide in combination with Mycobacterium tuberculosis in BCG vaccine is characterized by a significantly higher granuloma-inducing activity than BCG or silicon dioxide alone. Cell "dissociation" from granulomas is not characteristic of granulomas induced by silicon dioxide or its combination with BCG (in contrast to BCG-induced granulomas). A steady increase in the counts and size, particularly on days 120-180, mainly at the expense of fibroblast accumulation and subtotal fibrosis, are intrinsic to these granulomas. Monocyte retention in the bone marrow is characteristic starting from day 56 until day 180 after injection of both granulomatous factors alone or in combination, particularly so in BCG granulomatosis.


Asunto(s)
Granuloma/inmunología , Sistema Mononuclear Fagocítico/inmunología , Silicotuberculosis/inmunología , Animales , Vacuna BCG , Granuloma/etiología , Hígado/patología , Masculino , Ratones , Ratones Endogámicos CBA , Silicosis/inmunología , Silicotuberculosis/patología
17.
Arkh Patol ; 72(1): 16-9, 2010.
Artículo en Ruso | MEDLINE | ID: mdl-20369578

RESUMEN

The authors comparatively studied the nosological structure of congenital malformations (CM) in 395 fetuses at 22-27 weeks post-conception age and the efficiency of prenatal diagnosis in Novosibirsk. They analyzed 227 and 168 autopsy protocols of fetuses with CM over the periods from 2000 to 2002 and from 2006 to 2008, respectively. In the nosological structure of mortality among low-weight fetuses, CM ranked third in 2000-2002 and second in 2006-2008. During all the observation periods, the structure of CM showed 4 major systemic CMs: multiple anomalies of development, the central nervous and urogenital systems, heart, and vessels; multiple CMs occupying a prominent place. There was a preponderance of hydrocephalus and spinal hernias among central nervous system CMs, that of hydronephrosis with megaureter among urogenital CMs, and that of ventricular septal defect among CMs of the heart and vessels. The efficiency of prenatal diagnosis in the above observation periods was 46-75%.


Asunto(s)
Anomalías Congénitas/epidemiología , Anomalías Congénitas/patología , Enfermedades Fetales/epidemiología , Enfermedades Fetales/patología , Anomalías Congénitas/diagnóstico , Femenino , Enfermedades Fetales/diagnóstico , Humanos , Masculino , Embarazo , Diagnóstico Prenatal , Estudios Retrospectivos , Siberia
18.
Arkh Patol ; 72(1): 14-6, 2010.
Artículo en Ruso | MEDLINE | ID: mdl-20369577

RESUMEN

The nosological structure of mortality was studied among low-weight fetuses, by analyzing 667 autopsy protocols over 2006-2008. There were 255 cases of spontaneous miscarriage and 412 cases of medically indicated abortion. Spontaneous and artificial abortions most frequently occur in repeated pregnant women at 26-27 weeks gestational age. In the nosological structure of fetal mortality, intrauterine fetal asphyxia was most commonly in spontaneous miscarriage; intrauterine pneumonias and generalized infection ranked second; in artificial abortion, the number of congenital malformations doubled and that of intrauterine fetal asphyxia reduced. In spontaneous and artificial abortions, the incidence of decompensated chronic placental insufficiency increased by twice.


Asunto(s)
Aborto Legal/efectos adversos , Muerte Fetal/epidemiología , Peso Fetal , Número de Embarazos , Complicaciones Infecciosas del Embarazo/mortalidad , Adulto , Femenino , Humanos , Masculino , Embarazo , Estudios Retrospectivos , Siberia/epidemiología
19.
Science ; 359(6378): 887-891, 2018 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-29472477

RESUMEN

Light detection and ranging is widely used in science and industry. Over the past decade, optical frequency combs were shown to offer advantages in optical ranging, enabling fast distance acquisition with high accuracy. Driven by emerging high-volume applications such as industrial sensing, drone navigation, or autonomous driving, there is now a growing demand for compact ranging systems. Here, we show that soliton Kerr comb generation in integrated silicon nitride microresonators provides a route to high-performance chip-scale ranging systems. We demonstrate dual-comb distance measurements with Allan deviations down to 12 nanometers at averaging times of 13 microseconds along with ultrafast ranging at acquisition rates of 100 megahertz, allowing for in-flight sampling of gun projectiles moving at 150 meters per second. Combining integrated soliton-comb ranging systems with chip-scale nanophotonic phased arrays could enable compact ultrafast ranging systems for emerging mass applications.

20.
Nat Commun ; 8(1): 736, 2017 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-28963496

RESUMEN

Dissipative solitons are self-localised structures resulting from the double balance of dispersion by nonlinearity and dissipation by a driving force arising in numerous systems. In Kerr-nonlinear optical resonators, temporal solitons permit the formation of light pulses in the cavity and the generation of coherent optical frequency combs. Apart from shape-invariant stationary solitons, these systems can support breathing dissipative solitons exhibiting a periodic oscillatory behaviour. Here, we generate and study single and multiple breathing solitons in coherently driven microresonators. We present a deterministic route to induce soliton breathing, allowing a detailed exploration of the breathing dynamics in two microresonator platforms. We measure the relation between the breathing frequency and two control parameters-pump laser power and effective-detuning-and observe transitions to higher periodicity, irregular oscillations and switching, in agreement with numerical predictions. Using a fast detection, we directly observe the spatiotemporal dynamics of individual solitons, which provides evidence of breather synchronisation.Dissipative Kerr solitons enable optical frequency comb generation in microresonators, but these solitons can undergo a breathing transition which impacts the stability of such microcombs. Here, Lucas et al. deterministically induce soliton breathing and directly observe the spatiotemporal dynamics.

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