33 research outputs found
Gender differences in the structure of the cerebrospinal fluid system of pre-school children
Relevance Investigation of the cerebrospinal fluid system of children of different ages, especially pre-school and school periods of childhood, becomes essential, since the further development of the brain and its proper functioning depends on the way it functions. Considering the MRI indications of the elements of the cerebrospinal fluid system of children is important for the development of neurology and neurosurgery, it is necessary to consider gender differences in the brain size and structure.Objective To study the sex differences in the structure of the cerebrospinal fluid system in seven-year-old children.Material and Methods For the study, archival data on the sizes of the lateral ventricles of the brain of 120 children aged 7 (60 boys and 60 girls) were involved, in particular: 1) the length of the anterior horn; 2) the width of the anterior horn; 3) the length of the central part; 4) the width of the central part; 5) the length of the posterior horn; 6) the width of the posterior horn; 7) the length of the lower horn; 8) the anteroposterior size; 9) the distance between the anterior horns; 10) the distance between the posterior horns; 11) the length of the third ventricle; 12) the height of the third ventricle; 13) the length of the aqueduct; 14) the length of the fourth ventricle; 15) the height of the fourth ventricle. The studies were carried out using the method of magnetic resonance imaging. Quantitative indicators were assessed for compliance with the normal distribution using the KolmogorovSmirnov test. The accumulation, correction, systematization of the initial information were carried out in Microsoft Excel 2016. Statistical analysis was carried out using the Statistica 10.0 software (StatSoft Inc., USA). The results were considered statistically significant at p < 0.05.Results The data obtained in the study of the cerebrospinal fluid system in children during their pre-school period of childhood are indicators of the norm and can be used for diagnostic studies in the departments of radiation diagnostics. The bilateral asymmetry of the lateral ventricles of the brain in pre-school children, discovered during the work, is of crucial clinical significance. The morphometric indicators of the elements of the cerebrospinal fluid system should be considered by specialists in the study of brain neuroplasticity.Conclusion Analysis of the obtained in vivo encephalometric data indicates the presence of sexual variability of the brain and parameters of the structures of the cerebrospinal fluid
SOMATOTYPOLOGICAL CHARACTERISTIC OF THE REPRESENTATIVES OF DIFFERENT AGE PERIODS AND ITS IMPORTANCE IN SPORTS ORIENTATION
Aim. The study was designed for the theoretical analysis of the somatotypological characteristics of people of the second childhood, adolescent, youthful and mature age periods and their importance for sports orientation.Materials and methods. In course of the theoretical analysis, the search was performed in Scopus, eLIBRARY and PubMed databases using the keywords “somatotype”, “morphometry”, “somatometry”.Results. The presented materials are considered from the ecological, geographical, ethnical and territorial perspectives that have a significant impact on the constitutional heterogeneity of the population. The features of the somatotypological characteristics of boys and girls participating in various sports are being specified. Concluding the analysis of the literature, it can be stated that in a number of studies, certain ratios of the main body types were observed in healthy individuals of various ethnical and territorial groups. However, upon closer acquaintance with this material, significant contradictions are revealed regarding the nature and the degree of manifestation of these shifts, and, in some cases, even mutually exclusive statements are made.Conclusion. In view of the above, it is possible to conclude that further systematic study of these issues is needed
Temporal and spectral cloud screening of polar winter aerosol optical depth (AOD): impact of homogeneous and inhomogeneous clouds and crystal layers on climatological-scale AODs
We compared star-photometry-derived, polar winter aerosol optical depths
(AODs), acquired at Eureka, Nunavut, Canada, and Ny-Ă…lesund, Svalbard,
with GEOS-Chem (GC) simulations as well as ground-based lidar and
CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization)
retrievals over a sampling period of two polar winters. The results indicate
significant cloud and/or low-altitude ice crystal (LIC) contamination which
is only partially corrected using temporal cloud screening. Spatially
homogeneous clouds and LICs that remain after temporal cloud screening
represent an inevitable systematic error in the estimation of AOD: this
error was estimated to vary from 78 to 210 % at Eureka and from 2
to 157 % at Ny-Ålesund. Lidar analysis indicated that LICs appeared to
have a disproportionately large influence on the homogeneous coarse-mode
optical depths that escape temporal cloud screening. In principle, spectral
cloud screening (to yield fine-mode or submicron AODs) reduces
pre-cloud-screened AODs to the aerosol contribution if one assumes that
coarse-mode (super-micron) aerosols are a minor part of the AOD. Large, low-frequency differences between these retrieved values and their GC analogue
appeared to be often linked to strong, spatially extensive planetary
boundary layer events whose presence at either site was inferred from CALIOP
profiles. These events were either not captured or significantly
underestimated by the GC simulations. High-frequency AOD variations of GC
fine-mode aerosols at Ny-Ă…lesund were attributed to sea salt, while low-frequency GC variations at Eureka and Ny-Ă…lesund were attributable to
sulfates. CALIOP profiles and AODs were invaluable as spatial and temporal
redundancy support (or, alternatively, as insightful points of contention)
for star photometry retrievals and GC estimates of AOD
Springtime Arctic aerosol: Smoke versus Haze, a case study for March 2008
During March 2008 photometer observations of Arctic aerosol were performed both at a Russian ice-floe drifting station (NP-35) at the central Arctic ocean (56.7e42.0 E, 85.5e84.2 N) and at Ny-Ålesund, Spitsbergen (78.9 N, 11.9 E). Next to a persistent increase of AOD over NP-35, two pronounced aerosol events have been recorded there, one originating from early season forest fires close to the city of Khabarovsk (“Arctic Smoke”), the other one showed trajectories from central Russia and resembled more the classical Arctic Haze. The latter event has also been recorded two days later over Ny-Ålesund, both in photometer and lidar. From these remote sensing instruments volume distribution functions are derived and discussed. Only subtle differences between the smoke and the haze event have been found in terms of particle microphysics. Different trajectory analysis, driven by NCEP and ECMWF have been performed and compared. For the data set presented here the meteorological field, due to sparseness of data in the central Arctic, mainly limits the precision of the air trajectories
Synchronous polar winter starphotometry and lidar measurements at a High Arctic station
We present recent progress on nighttime retrievals of aerosol and cloud
optical properties over the PEARL (Polar Environmental Atmospheric Research
Laboratory) station at Eureka (Nunavut, Canada) in the High Arctic
(80° N, 86° W). In the spring of 2011 and 2012, a
star photometer was employed to acquire aerosol optical depth (AOD) data, while
vertical aerosol and cloud backscatter profiles were measured using the
CANDAC Raman Lidar (CRL). We used a simple backscatter coefficient threshold
(β<sub>thr</sub>) to distinguish aerosols from clouds and, assuming that
aerosols were largely fine mode (FM)/sub-micron, to distinguish FM aerosols
from coarse mode (CM)/super-micron cloud or crystal particles. Using
prescribed lidar ratios, we computed FM and CM AODs that were compared with
analogous AODs estimated from spectral star photometry. We found
(β<sub>thr</sub> dependent) coherences between the lidar and
star photometer for both FM events and CM cloud and crystal events with
averaged, FM absolute differences being <∼0.03 when associated
<i>R</i><sup>2</sup> values were between 0.2 and 0.8. A β<sub>thr</sub> sensitivity
study demonstrated that zero crossing absolute differences and <i>R</i><sup>2</sup> peaks
were in comparable regions of the β<sub>thr</sub> range (or physical
reasons were given for their disparity). The utility of spectral vs.
temporal cloud screening of star photometer AODs was also illustrated. In
general our results are critical to building confidence in the physical
fidelity of derived, weak amplitude, star photometry AODs and, in turn,
towards the development of AOD climatologies and validation databases for
polar winter models and satellite sensors