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Fast radio bursts are millisecond-duration, extragalactic radio flashes of unknown physical origin. The only known repeating fast radio burst source-FRB 121102-has been localized to a star-forming region in a dwarf galaxy at redshift 0.193 and is spatially coincident with a compact, persistent radio source. The origin of the bursts, the nature of the persistent source and the properties of the local environment are still unclear. Here we report observations of FRB 121102 that show almost 100 per cent linearly polarized emission at a very high and variable Faraday rotation measure in the source frame (varying from +1.46 × 105 radians per square metre to +1.33 × 105 radians per square metre at epochs separated by seven months) and narrow (below 30 microseconds) temporal structure. The large and variable rotation measure demonstrates that FRB 121102 is in an extreme and dynamic magneto-ionic environment, and the short durations of the bursts suggest a neutron star origin. Such large rotation measures have hitherto been observed only in the vicinities of massive black holes (larger than about 10,000 solar masses). Indeed, the properties of the persistent radio source are compatible with those of a low-luminosity, accreting massive black hole. The bursts may therefore come from a neutron star in such an environment or could be explained by other models, such as a highly magnetized wind nebula or supernova remnant surrounding a young neutron star.
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Fast radio bursts are astronomical radio flashes of unknown physical nature with durations of milliseconds. Their dispersive arrival times suggest an extragalactic origin and imply radio luminosities that are orders of magnitude larger than those of all known short-duration radio transients. So far all fast radio bursts have been detected with large single-dish telescopes with arcminute localizations, and attempts to identify their counterparts (source or host galaxy) have relied on the contemporaneous variability of field sources or the presence of peculiar field stars or galaxies. These attempts have not resulted in an unambiguous association with a host or multi-wavelength counterpart. Here we report the subarcsecond localization of the fast radio burst FRB 121102, the only known repeating burst source, using high-time-resolution radio interferometric observations that directly image the bursts. Our precise localization reveals that FRB 121102 originates within 100 milliarcseconds of a faint 180-microJansky persistent radio source with a continuum spectrum that is consistent with non-thermal emission, and a faint (twenty-fifth magnitude) optical counterpart. The flux density of the persistent radio source varies by around ten per cent on day timescales, and very long baseline radio interferometry yields an angular size of less than 1.7 milliarcseconds. Our observations are inconsistent with the fast radio burst having a Galactic origin or its source being located within a prominent star-forming galaxy. Instead, the source appears to be co-located with a low-luminosity active galactic nucleus or a previously unknown type of extragalactic source. Localization and identification of a host or counterpart has been essential to understanding the origins and physics of other kinds of transient events, including gamma-ray bursts and tidal disruption events. However, if other fast radio bursts have similarly faint radio and optical counterparts, our findings imply that direct subarcsecond localizations may be the only way to provide reliable associations.
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OBJECTIVES: Since Russia's full-scale invasion of Ukraine on 24 February 2022, millions of people have fled the country. Most people have gone to the neighbouring countries of Poland, Slovakia, Hungary, Romania, and Moldova. This vulnerable population has significant healthcare needs. Among the most challenging to address will be chronic non-communicable diseases (NCDs), including mental disorders, as these require long-term, continuous care and access to medicines. Host country health systems are faced with the challenge of ensuring accessible and affordable care for NCDs and mental disorders to this population. Our objectives were to review host country health system experiences and identify priorities for research to inform sustainable health system responses to the health care needs of refugees from Ukraine. STUDY DESIGN: In-person conference workshop. METHODS: A workshop on this subject was held in November 2022 at the European Public Health Conference in Berlin. RESULTS: The workshop included participants from academia and non-governmental organisations, health practitioners, and World Health Organisation regional and country offices. This short communication reports the main conclusions from the workshop. CONCLUSION: Addressing the challenges and research priorities identified will require international solidarity and co-operation.
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Refugiados , Humanos , Atención a la Salud , Polonia , Hungría , RumaníaRESUMEN
Fast radio bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of these bursts has led to the suggestion that they originate in cataclysmic events. Here we report observations of ten additional bursts from the direction of the fast radio burst FRB 121102. These bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast radio bursts, these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star.
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The tissue reaction of pig skin to implantation of decellularized and recellularized dermal matrices on a formed wound defect was evaluated by histological methods on days 2, 5, 8, 16, and 20 after surgery. Differences in tissue response to different matrices were identified. In experimental wounds coated with decellularized dermal matrices, we observed the formation of a scar tissue, which required autodermoplasty on day 12 of the experiment. In wounds coated with recellularized dermal matrices, all layers of the skin completely recovered by day 20 after surgery with the formation of full dermal and epidermal layers. Our findings suggest that reparative morphological changes in the wound depend on the presence of fibroblasts in the implanted dermal matrix.
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Piel/citología , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Animales , Matriz Extracelular , Fibroblastos/citología , Porcinos , Cicatrización de Heridas/fisiologíaRESUMEN
The authors describe successful treatment of a patient with consequences of a mine-explosive wound of the right thigh and abdomen, including damage to the duodenum. Staged surgical treatment made it possible to identify and eliminate defects in primary surgical treatment in time. Thus, favorable treatment results were obtained.
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Traumatismos Abdominales , Traumatismos por Explosión , Abdomen , Traumatismos Abdominales/complicaciones , Traumatismos Abdominales/diagnóstico , Traumatismos Abdominales/cirugía , Traumatismos por Explosión/complicaciones , Traumatismos por Explosión/diagnóstico , Traumatismos por Explosión/cirugía , Duodeno/diagnóstico por imagen , Duodeno/cirugía , HumanosRESUMEN
BACKGROUND: There is mounting evidence supporting the effectiveness of task-shifted mental health interventions in low- and middle-income countries (LMIC). However, there has been limited systematic scale-up or sustainability of these programs, indicating a need to study implementation. One barrier to progress is a lack of locally relevant and valid implementation measures. We adapted an existing brief dissemination and implementation (D&I) measure which includes scales for acceptability, appropriateness, feasibility and accessibility for local use and studied its validity and reliability among a sample of consumers in Ukraine. METHODS: Local qualitative data informed adaptation of the measure and development of vignettes to test the reliability and validity. Participants were veterans and internally displaced persons (IDPs) recruited as part of a separate validity study of adapted mental health instruments. We examined internal consistency reliability, test-retest reliability, and construct and criterion validity for each scale on the measure. We randomly assigned half the participants to respond to a vignette depicting existing local psychiatric services which we knew were not well regarded, while the other half was randomized to a vignette describing a potentially more well-implemented mental health service. Criterion validity was assessed by comparing scores on each scale by vignette and by overall summary ratings of the programs described in the vignettes. RESULTS: N = 169 participated in the qualitative study and N = 153 participated in the validity study. Qualitative findings suggested the addition of several items to the measure and indicated the importance of addressing professionalism/competency of providers in both the scales and the vignettes. Internal consistency reliabilities ranged from α = 0.85 for feasibility to α = 0.91 for appropriateness. Test-rest reliabilities were acceptable to good for all scales (rho: 0.61-0.79). All scales demonstrated substantial and significant differences in average scores by vignette assignment (ORs: 2.21-5.6) and overall ratings (ORs: 5.1-14.47), supporting criterion validity. CONCLUSIONS: This study represents an innovative mixed-methods approach to testing an implementation science measure in contexts outside the United States. Results support the reliability and validity of most scales for consumers in Ukraine. Challenges included large amounts of missing data due to participants' difficulties responding to questions about a hypothetical program.
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Salud Global , Ciencia de la Implementación , Servicios de Salud Mental/organización & administración , Servicios de Salud Mental/normas , Humanos , Psicometría , Investigación Cualitativa , Reproducibilidad de los Resultados , Proyectos de Investigación , UcraniaRESUMEN
Solid-state quantum emitters are prime candidates for the realization of fast, on-demand single-photon sources. The improvement in photon emission rate and collection efficiency for point-like emitters can be achieved by using a near-field coupling to nanophotonic structures. Plasmonic metamaterials with hyperbolic dispersion have previously been demonstrated to significantly increase the fluorescence decay rates from dipolar emitters due to a large broadband density of plasmonic modes supported by such metamaterials. However, the emission coupled to the plasmonic modes must then be outcoupled into the far field before it succumbs to ohmic losses. We propose a nano-grooved hyperbolic metamaterial that improves the collection efficiency by several times compared to a conventional planar lamellar hyperbolic metamaterial. Our approach can be utilized to achieve broadband enhancement of emission for diverse types of quantum emitters.
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It was described the results of endosurgical treatment different technique of 170 children of both sexes aged 4 months to 14 years. Children had inguinal hernia. There were unilateral hernia in 148 patients and bilateral hernia in 22 patients. It was used such interventions as laparoscopic herniotomy with hernial sac extirpation (6 operations), laparoscopic suturing of deep inguinal ring (22 operations), dual-port laparoscopic extraperitoneal herniorrhaphy (46 operations), original single-port laparoscopic extraperitoneal herniorrhaphy (118 operations). The minimum duration of the operation (4.5-7.5 minutes) was observed in the last group. These patients did not need postoperative anesthesia. Relapse was detected in 2 (1.1%) cases. Developed single-port laparoscopic extraperitoneal herniorrhaphy may be alternative in children with inguinal hernia.
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Hernia Inguinal , Herniorrafia , Conducto Inguinal/cirugía , Cuidados Intraoperatorios , Laparoscopía , Complicaciones Posoperatorias/prevención & control , Niño , Femenino , Hernia Inguinal/diagnóstico , Hernia Inguinal/cirugía , Herniorrafia/efectos adversos , Herniorrafia/métodos , Humanos , Cuidados Intraoperatorios/efectos adversos , Cuidados Intraoperatorios/métodos , Laparoscopios , Laparoscopía/efectos adversos , Laparoscopía/instrumentación , Laparoscopía/métodos , Masculino , Recurrencia/prevención & control , Estudios Retrospectivos , Técnicas de Sutura , Resultado del TratamientoRESUMEN
Due to its high carbohydrate content honey is an excellent energy source and possesses some functional effects. It is especially valuable for children and sportsmen. The glycemic index of honey varies from 32 to 91 depending on botanical origin. Honey contains also a great number of other constituents in small and trace amounts. This composition possesses numerous nutritional and biological effects: antimicrobial, antioxidant, prebiotic, immunomodulating activities. There is a suggestion on consumption rates.
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Alimentos Funcionales , Miel , Animales , Antiinfecciosos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Alimentos Funcionales/análisis , Alimentos Funcionales/clasificación , Miel/análisis , Miel/clasificación , Humanos , Factores Inmunológicos/aislamiento & purificación , Valor Nutritivo , Prebióticos , Probióticos/aislamiento & purificaciónRESUMEN
Two patients with cystic dystrophy of duodenum and chronic inflammation of duodenally ectopic pancreatic tissue were successfully operated on. Both cases clinically demonstrated abdominal pain and duodenal obstruction. Absence of substantial tissue changes in "main" pancreas allowed execution of pancreas-preserving operation. Thus, subtotal duodenectomy was performed in the first patient. The second patient had resection of vertical branch of the duodenum with intestinal fragment replacement. Extensive periorganic fibrosis in both cases substantially complicated verification of anatomic structures and dissection.
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Coristoma/cirugía , Conducto Colédoco/cirugía , Quistes/cirugía , Duodenitis/cirugía , Conductos Pancreáticos , Pancreaticoduodenectomía/métodos , Adulto , Quistes/diagnóstico por imagen , Duodenitis/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada por Rayos XRESUMEN
The amount of food necessary to cause within-session decreases in response rates was investigated by varying reinforcer duration (Experiment 1) and grain size (Experiment 2). Within-session response rates quickly increases to a peak, and the decrease throughout the rest of the session was greater for conditions with larger amounts of food. The decreases were greatest for the pigeons that ate the least when food was freely available. Previous studies of within-session changes in responding are reviewed and reinterpreted. It was concluded that satiation causes the decrease in responding and that this effect is not restricted to extreme manipulations of the amount of food consumed.
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Condicionamiento Operante , Saciedad , Animales , Columbidae , Ingestión de Alimentos , Esquema de RefuerzoRESUMEN
A study on the possible degradation of amitraz, bromopropylate, coumaphos, chlordimeform, cymiazole, flumethrin, and tau-fluvalinate during the storage of honey was carried out by HPLC. Except amitraz, the other acaricides are stable in this medium for at least 9 months. Degradation studies of amitraz in honey and beeswax were carried out; the degradation products detected in both matrices were 2,4-dimethylphenylformamide (DMF) and N-(2,4-dimethylphenyl)-N'-methylformamidine (DPMF). The reaction rate constants and the half-lives of the amitraz degradation in honey and wax were calculated. Amitraz was nearly completely degraded within 1 day in beeswax and within 10 days in honey. When amitraz-spiked combs are recycled into new beeswax, DMF was found to be the principal degradation product left in pure wax.
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Miel/análisis , Ceras/química , Animales , Abejas , Biodegradación Ambiental , Cromatografía Líquida de Alta Presión , Semivida , Insecticidas/farmacocinética , Cinética , Factores de Tiempo , Toluidinas/farmacocinéticaRESUMEN
A nuclear photographic emulsion method was used to study the charge-state, ionization, and angular characteristics of secondaries produced in inelastic interactions of 56Fe nuclei at 1.8 GeV/nucleon with H, CNO, and AgBr nuclei. The data obtained are compared with the results of calculations made in terms of the Dubna version of the cascade evaporation model (DCM). The DCM has been shown to satisfactorily describe most of the interaction characteristics for two nuclei in the studied reactions. At the same time, quantitative differences are observed in some cases.
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Partículas Elementales , Emulsiones/química , Hierro/química , Modelos Teóricos , Bromuros/química , Carbono/química , Radiación Cósmica , Transferencia de Energía , Hidrógeno/química , Matemática , Nitrógeno/química , Física Nuclear , Oxígeno/química , Compuestos de Plata/químicaRESUMEN
Nuclear photographic emulsion is used to study the dependence of the characteristics of target-nucleus fragments on the masses and impact parameters of interacting nuclei. The data obtained are compared in all details with the calculation results made in terms of the Dubna version of the cascade-evaporation model (DCM).
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Partículas Elementales , Emulsiones/química , Hierro/química , Modelos Teóricos , Partículas alfa , Bromuros/química , Carbono/química , Transferencia de Energía , Matemática , Nitrógeno/química , Física Nuclear , Oxígeno/química , Protones , Compuestos de Plata/químicaRESUMEN
A method is proposed for finding the dependence of mean multiplicities of secondaries on the nucleus-collision impact parameter from the data on the total interaction ensemble. The impact parameter has been shown to completely define the mean characteristics of an individual interaction event. A difference has been found between experimental results and the data calculated in terms of the cascade-evaporation model at impact-parameter values below 3 fm.
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Hierro , Neón , Física Nuclear , Partículas Elementales , Emulsiones , Matemática , Modelos Teóricos , ProtonesRESUMEN
Multiplicities of various species of charged secondaries produced in inelastic interactions of 20Ne, 40Ar and 56Fe nuclei with emulsion nuclei at 0.1-0.5 GeV/nucleon have been measured. The data obtained are compared with the results for interactions of higher energy nuclei with emulsion nuclei. The dependences of the nucleus-nucleus interaction parameters on masses and energies of colliding nuclei are examined.
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Argón , Hierro , Neón , Física Nuclear , Dispersión de Radiación , Partículas Elementales , Iones , Matemática , Modelos TeóricosRESUMEN
The article gives an account of material concerning treatment of 60 patients with pigmented lesions of the skin (capillary hemangiomas, pigmented nevus, tattoos) by exposure to argon laser radiation. The optimal regimens and doses of laser radiation for discoloration of pigmented skin lesions are stated. Methodological recommendations for applying three methods fo laser treatment of extensive capillary hemangiomas are suggested. The method used by the authors for treating pigmented skin lesions produced good and satisfactory cosmetic results in 95% of cases.
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Terapia por Láser , Enfermedades de la Piel/cirugía , Hemangioma/cirugía , Humanos , Queratosis/cirugía , Nevo Pigmentado/cirugía , Neoplasias Cutáneas/cirugía , Tatuaje , Telangiectasia/cirugíaRESUMEN
During 10 years there were 94 patients aged 16-68 years with injuries of the duodenum. Their case histories were studied in order to establish the causes of complications and lethality. Among them there were 48 patients with knife wounds, 5 patients with gunshot wounds, closed trauma of the abdomen was diagnosed in 40 patients, 1 patient had a iatrogenic wound of the duodenum. There were 17 isolated injuries of the gut and 77 combined and multiple injuries. Patients with traumatic perforations in the duodenum made up 89.4%, 31% of them died. In 70 patients suture of the duodenum was put during operation, 10 patients had sutures and intubation of the duodenum, in 6 patients the injured gut was excluded, in 1 patient resection of the duodenum was made and primary anastomosis was formed. 28 patients (29.8%) died. Among the causes of the deaths were non-compensated blood loss resulting from hemorrhage from the vessels of the liver and other organs, combined and multiple injuries. Pyo-septic complications led to death of 12 patients, duodenal fistula was found in 4 patients. An analysis of the material has shown that most patients with traumas of the duodenum could be cured by suturing the incised or lacerated wound of the duodenum. Exclusion of the duodenum is thought to be a helpful addition to operation on the injured duodenum, especially on large wounds. Pancreatoduodenectomy is necessary but seldom in surgery of such traumas.
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Duodeno/lesiones , Perforación Intestinal/etiología , Heridas por Arma de Fuego/cirugía , Heridas no Penetrantes/cirugía , Heridas Punzantes/cirugía , Adolescente , Adulto , Anciano , Enfermedades Duodenales/etiología , Humanos , Fístula Intestinal/etiología , Perforación Intestinal/mortalidad , Perforación Intestinal/cirugía , Persona de Mediana Edad , Complicaciones Posoperatorias , Factores de Tiempo , Heridas por Arma de Fuego/mortalidad , Heridas no Penetrantes/mortalidad , Heridas Punzantes/mortalidadRESUMEN
Complex prophylactics of pyo-septic complications was used in 46 patients with acute destructive pancreatitis. It resulted in 11% less frequency of the complications, postoperative lethality became 28% lower. In 35 patients with the preserved spleen resection of the pancreas was followed by less lethality as compared with similar operations including splenectomy. The immune stimulating therapy in combination with antibiotics ++ is most effective after radical operations on the pancreas.