► We studied cadmium-by-mercury chemical substitution in CdSe nanocrystals. ► Zinc blende CdSe quantum dots can be easily converted to isostructural CdxHg1−xSe. ► Wurtzite CdSe QDs require longer ...time to convert to a zinc blende CdxHg1−xSe. ► Wurtzite CdSe nanorods transform to nanoheterogeneous luminescent CdxHg1−xSe rods.
The chemical substitution of cadmium by mercury in colloidal CdSe quantum dots (QDs) and nanorods has been examined by absorption, photoluminescence and Raman spectroscopy. The crystalline structure of original CdSe QDs used for Cd/Hg substitution (zinc blende versus wurtzite) shows a strong impact on the optical and structural properties of resultant CdxHg1−xSe nanocrystals. Substitution of Cd by Hg in isostructural zinc blende CdSe QDs converts them to ternary CdxHg1−xSe zinc blende nanocrystals with significant NIR emission. Whereas, the wurtzite CdSe QDs transformed first to ternary nanocrystals with almost no emission followed by slow structural reorganization to a NIR-emitting zinc blende CdxHg1−xSe QDs. CdSe nanorods with intrinsic wurtzite structure show unexpectedly intense NIR emission even at early Cd/Hg substitution stage with PL active zinc blende CdxHg1−xSe regions.
The article presents a study of the connection between the number and area of forest fires on the territory of the Amur Region from the area of forestries. the length of mineralized belts in each ...forestry. the natural class of fire hazard. and the class of fire hazard by weather conditions. A stable relationship between the number of forest fires and the fire hazard class by weather conditions has been revealed. This dependence is presented in the form of a model that makes it possible to predict the number of forest fires both on the territory of the forest fund of the entire Amur Region. and for individual forestries.
The aim of this study was to investigate the efficacy of etanercept treatment and to identify predictors of response to therapy within 12 months in patients with juvenile idiopathic arthritis (JIA) ...without systemic manifestations.
A total of 197 juvenile patients were enrolled in this study. Response to therapy was assessed using the ACRPedi 30/50/70/90 criteria, the Wallace criteria, and the Juvenile Arthritis Disease Activity Score 71 (JADAS-71). Univariate and multivariate logistic regression analyses were performed to identify potential baseline factors associated with treatment response in different JIA categories.
One year after treatment initiation, 179 (90.9%) patients achieved ACRPedi30; 177 (89.8%) patients achieved ACRPedi50; 168 (85.3%) patients achieved ACRPedi70; and 135 (68.5%) patients achieved ACRPedi90 response. A total of 132 (67.0%) and 92 (46.7%) patients achieved inactive disease according to the Wallace criteria and the JADAS-71 cut-off point, respectively. Excellent response (achieving ACRPedi90 and clinically inactive disease according both to the Wallace criteria and the JADAS71 cut-off point) was associated with persistent oligoarticular JIA category, shorter disease duration before the start of etanercept, a lower number of DMARDs used before the introduction of etanercept, a lower number of joints with limited motion, and lower C-reactive protein at baseline. Poor response (failure to achieve ACR 70 or active disease according to both the Wallace criteria and JADAS71 even when ACR 70 was achieved) was associated with the polyarticular or enthesitis-related JIA categories, higher disease duration before the start of etanercept, and older age at disease onset.
Almost half (45.7%) of the patients who initiated etanercept treatment achieved an excellent response (inactive disease and ACRPedi90) after 1 year. What may be novel is our finding that the response to etanercept therapy was strongly associated with the JIA category. The response to etanercept therapy was also associated with the disease duration before the start of etanercept treatment.
This research studies eff ects of technology factors on strength and durability of fi bre reinforced concrete. It theoretically proves the infl uence of elastic aftereff ect deformation values on fi ...bre reinforced concrete strength and durability. The paper proves that high-modulus fi ber reinforcement leads to lowering the eff ects of the infl uence of elastic aftereff ect deformation on fi bre reinforced concrete strength and durability. It also demonstrates that basalt fi bre and superplasticizing admixture C-3 integrated use in fi bre reinforced concrete reduces the deformation value of elastic aftereff ect to 25% and makes it possible to obtain a material with FI 400 and above frost resistance properties.
On April 26, 1986, an accident at the Chernobyl nuclear power station in the Soviet Union exposed about 200 people to large doses of total-body radiation. Thirteen persons exposed to estimated ...total-body doses of 5.6 to 13.4 Gy received bone marrow transplants. Two transplant recipients, who received estimated doses of radiation of 5.6 and 8.7 Gy, are alive more than three years after the accident. The others died of various causes, including burns (the cause of death in five), interstitial pneumonitis (three), graft-versus-host disease (two), and acute renal failure and adult respiratory distress syndrome (one). There was hematopoietic (granulocytic) recovery in nine transplant recipients who could be evaluated, six of whom had transient partial engraftment before the recovery of their own marrow. Graft-versus-host disease was diagnosed clinically in four persons and suspected in two others. Although the recovery of endogenous hematopoiesis may occur after exposure to radiation doses of 5.6 to 13.4 Gy, we do not know whether it is more likely after the transient engraftment of transplanted stem cells. Because large doses of radiation affect multiple systems, bone marrow recovery does not necessarily ensure survival. Furthermore, the risk of graft-versus-host disease must be considered when the benefits of this treatment are being weighed.
Considerable data suggest that very high doses of acute total body radiation destroy most hematopoietic stem cells and that recovery is possible only after a bone marrow transplant. We review data ...from a radiation accident victim exposed to about 10-Gy or more acute total body radiation. Total dose and uniformity of distribution were confirmed by physical measurements (paramagnetic resonance), computer simulation, and biologic dosimetry (granulocyte kinetics and cytogenetic abnormalities). Treatment consisted of supportive measures, transfusions, and hematopoietic growth factors (granulocyte-macrophage colony-stimulating factor and interleukin-3). Hematopoietic recovery occurred slowly. Granulocytes were detectable throughout the postexposure period, exceeding 0.5 x 10(9)/L by day 37. There was slower and incomplete recovery of red blood cells and platelets. Increases in blood cell production were paralleled by morphologic changes in bone marrow biopsies. Gastrointestinal toxicity was moderate. Death from a probable radiation pneumonitis infection occurred on day 130. These data indicate the possibility of hematopoietic recovery after approximately 10 Gy or more acute total body radiation without a transplant. They also suggest that lung rather than gastrointestinal toxicity may be dose-limiting under these circumstances.
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