189 research outputs found
Analysis of global and regional CO burdens measured from space between 2000 and 2009 and validated by ground-based solar tracking spectrometers
Interannual variations in AIRS and MOPITT retrieved CO burdens are validated, corrected, and compared with CO emissions from wild fires from the Global Fire Emission Dataset (GFED2) inventory. Validation of daily mean CO total column (TC) retrievals from MOPITT version 3 and AIRS version 5 is performed through comparisons with archived TC data from the Network for Detection of Atmospheric Composition Change (NDACC) ground-based Fourier Transform Spectrometers (FTS) between March 2000 and December 2007. MOPITT V3 retrievals exhibit an increasing temporal bias with a rate of 1.4–1.8% per year; thus far, AIRS retrievals appear to be more stable. For the lowest CO values in the Southern Hemisphere (SH), AIRS TC retrievals overestimate FTS TC by 20%. MOPITT's bias and standard deviation do not depend on CO TC absolute values. Empirical corrections are derived for AIRS and MOPITT retrievals based on the observed annually averaged bias versus the FTS TC. Recently published MOPITT V4 is found to be in a good agreement with MOPITT V3 corrected by us (with exception of 2000–2001 period). With these corrections, CO burdens from AIRS V5 and MOPITT V3 (as well as MOPITT V4) come into good agreement in the mid-latitudes of the Northern Hemisphere (NH) and in the tropical belt. In the SH, agreement between AIRS and MOPITT CO burdens is better for the larger CO TC in austral winter and worse in austral summer when CO TC are smaller. Before July 2008, all variations in retrieved CO burden can be explained by changes in fire emissions. After July 2008, global and tropical CO burdens decreased until October before recovering by the beginning of 2009. The NH CO burden also decreased but reached a minimum in January 2009 before starting to recover. The decrease in tropical CO burdens is explained by lower than usual fire emissions in South America and Indonesia. This decrease in tropical emissions also accounts for most of the change in the global CO burden. However, no such diminution of NH biomass burning is indicated by GFED2. Thus, the CO burden decrease in the NH could result from a combination of lower fossil fuel emissions during the global economic recession and transport of CO-poor air from the tropics. More extensive modeling will be required to fully resolve this issue
Distinguishing different excitation pathways in two-dimensional terahertz-infrared-visible spectroscopy
РЕЗОНАНСНЫЕ ШИРОТНО-ИМПУЛЬСНЫЕ ПРЕОБРАЗОВАТЕЛИ
Circuit constructions of the DC-to-DC converter with an operated exchange of energy between reactive elements, namely the DC-to-DC converter of an output voltage step-up and step-down (buck-boost) type were described. In the case of the construction of the converter with an inductive storage element, DC-to-DC converter has half the number of reactive elements. Then in the environment of Simuling of the Matlab program a computer model for the specified DC-to-DC converter was created. With its help the operating characteristic was designed and analyzed. By measurements presented on screens of Display blocks, values of currents and voltages on the DC-to-DC converter elements and also all necessary power indicators on entrance and output clips of the converter were determined.Описаны схемные построения широтно-импульсных преобразователей (ШИП) с управляемым обменом энергии между реактивными элементами, а именно ШИП типа понижающе - повышающие выходное напряжение. Для случая построения преобразователя с индуктивным накопительным элементом, ШИП содержит вдвое меньшее число реактивных элементов. В дальнейшем в среде Simuling программы Matlab для указанного ШИП создана компьютерная модель. С её помощью построена и проанализирована регулировочная характеристика. По данным измерений, представленных на экранах блоков Display, определены величины токов и напряжений на элементах ШИП, а также все необходимые энергетические показатели на входных и выходных зажимах преобразователя
The 85<sup>th</sup> Anniversary of the V.A. Negovsky Research Institute of General Rehabilitology, Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology (Editorial)
Reanimatology (the science of resuscitation) represents the science of critical illness, terminal and postresuscitation conditions, originated within the walls of the V. A. Negovsky Research Institute of General Rean-imatology, Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, turns 85 years old on October 19, 2021. This editorial briefly describes the history of the development of the Institute, as well as the current scientific achievements of the Institute staff
Study of aversive and p38 mapk-inhibitory properties of kappa-agonist with analgesic activity-compound RU-1205
The clinical use of kappa-opioid agonists, despite their lack of significant drug potential, is limited by the development of severe sedation, dysphoria, depression, and anhedonia. To this date, there are kappa-opioid receptor agonists lacking these side effects due to the selective activation of intracellular signal transmission pathways without p38-MAPK-kinase activatio
Nueroprotection by Anesthetics in Brain Injury Models
The aim of the study was to compare the effect of sevoflurane and chloral hydrate on the neurological status and volume of brain damage after trauma and ischemia in experimental models of traumatic brain injury (TBI) and focal ischemic stroke (IS) induced by photothrombosis (PT).Materials and methods. The experiments were performed on mongrel Wistar rats weighing 250–300 g (N=43). There were 4 groups: the Ischemia + Sevoflurane group (ISSEV) (N=10), the Ischemia + Chloral hydrate group (ISCH) (N=10), TBI + Sevoflurane group (TBISEV) (N=13), and TBI+Chloral hydrate group (TBICH) (N=10). Ischemic brain damage was modelled using Rose Bengal (RB) dye-induced PT, and TBI was modelled using mechanical force-induced concussion.Results. MRI findings indicate lower volumes of brain damage (mm³) in rats from TBISEV group compared with the TBICH group (19±5 vs. 60±5, P<0.0001), and in the ISSEV group compared with the ISCH group (9.8±1.5 vs. 21.5±2, P=0.0016). Moreover, there was a significant difference between ISSEV and ISCH groups based on the protocol assessment of neurological status on day 14 with higher scores in ISSEV (11.4±1.8 vs. 4.9±2.6, P<0.0001).Conclusion. Taking into account the data obtained, we recommend a careful choice of anesthesia when modeling ischemic stroke and traumatic brain injury in animals. In particular, the neuroprotective effect of sevoflurane should be taken into account in the PT and TBI models
Comparative Characterization of Candidate Molecular Markers in Ischemic and Hemorrhagic Stroke
According to epidemiological studies, the leading cause of morbidity, disability and mortality are cerebrovascular diseases, in particular ischemic and hemorrhagic strokes. In recent years considerable attention has been given to the study of molecular markers of ischemic and hemorrhagic strokes. These studies are relevant because brain-specific protein biomarkers of neurons and glial cells can provide valuable and timely diagnostic information necessary for clinical decision-making.The aim of the study was to reveal the differences in the serum level of molecular markers in acute, subacute and early recovery periods of ischemic and hemorrhagic strokes.Material and methods. The study included 59 patients. Twenty patients were diagnosed with hemorrhagic stroke and 39 had ischemic stroke. The control group included 20 volunteers. Serum levels of molecular CNS markers were determined in acute, subacute, and early recovery stages of stroke. The serum levels of CNS molecular markers of patients with ischemic and hemorrhagic stroke was measured quantitatively by enzyme immunoassay. Statistical analysis was performed by nonparametric Mann-Whitney method.Results. The level of brain-derived neurotrophic factor (BDNF) in the control volunteers was 574.5 [455.5; 615] pg/ml. Significant differences were found for acute and subacute periods of hemorrhagic stroke: it was 674 [560; 749] pg/ml (P=0.003) and 664 [616; 762] pg/ml (P=0.0001).The level of neuron-specific enolase was significantly increased in all periods of the study: it was 4.15 [3.53; 4.8] ng/ml in the control group, 5.4 [4.4; 6.4] ng/ml in acute period of ischemic stroke (P<0.001), 5.4 [4.4; 6.4] ng/ml in early recovery period of ischemic stroke (P=0.001), 5.1 [4.6; 6.4] ng/ml in acute period of hemorrhagic stroke (P=0.014), 664 [616; 762] ng/ml in subacute period of hemorrhagic stroke (P=0.003).In the control group, the serum S-100 protein level was 4.5 [3.8; 5.4] ng/ml. In the acute and early recovery periods of ischemic stroke, S-100 protein level has significantly fallen down to 4.1 [3.4; 4.6] ng/ml (P<0.031) and 3.9 [3.4; 6] ng/ml (P=0.014), respectively. Glial-cell derived neurotrophic factor level was 1.98 [1.64; 2.1] ng/ml in the controls and increased up to 2.4 [2.2; 5] ng/ml (P=0.002) in the acute period and 2.4 [2.3; 2.6] ng/ml (P<0.001) in the subacute period of hemorrhagic stroke.The vascular endothelial growth factor receptor-1 (VEGFR-1) was significantly lower in the subacute period of hemorrhagic stroke: 485 [211; 945] pg/ml in the subacute period vs 903.5 [626; 1115] pg/ml in the controls (P=0.001).Conclusion. We found differences in the serum level of molecular markers in patients with ischemic and hemorrhagic strokes. In the acute period, early recovery period of ischemic stroke, and subacute period of hemorrhagic stroke, there was an increase in the serum level of neuron-specific enolase. The level of brain-derived neurotrophic factor increased significantly in the acute and subacute periods of hemorrhagic stroke. In the acute and early recovery periods of ischemic stroke, the level of S-100 protein decreased. The level of glial cell-derived neurotrophic factor increased in the acute and subacute periods of hemorrhagic stroke. In the subacute period of hemorrhagic stroke, the level of endothelial growth factor receptor-1 significantly decreased. Moreover, there was significant difference between values of this parameter in the subacute period of hemorrhagic stroke and in the early recovery period of ischemic stroke
Validation of five years (2003–2007) of SCIAMACHY CO total column measurements using ground-based spectrometer observations
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