A comparative study between children and adults with bacterial neuroinfections

Abstract Introduction: Bacterial meningitis is an acute purulent infection of the meninges. There are significant differences in the etiological spectrum, clinical course and outcome of bacterial meningitis in the age groups, and their recognition is important for early diagnosis and adequate therapy. Aim: The study aims to determine the differences in the etiology and clinical presentation of bacterial meningitis between children and adults. Materials and methods: The study included 90 patients (25 children and 65 adults) with bacterial neuroinfection admitted to St George University Hospital, Plovdiv between January 1, 2016 and September 31, 2019. We applied epidemiological and clinical analysis, microbiological and statistical methods. Results: In adults, the most common etiological agent was Streptococcus pneumoniae (20%), followed by Staphylococcus spp. (18.5%), Listeria monocytogenes (12.3%), Streptococcus spp. (3.1%), Haemophilus influenzae (3.1%), Klebsiella pneumoniae (1.5%), and Mycobacterium tuberculosis (1.5%). The etiological structure in children was different: Neisseria meningitidis (20%), Streptococcus pneumoniae (16%), Klebsiella pneumoniae (8%), Enterococcus faecium (8%), Streptococcus salivarius (4%), and Mycobacterium tuberculosis (4%). In 40% of the cases, both children and adults, the causative agent was not identified. Conclusions: Regarding the clinical presentation, a statistical significance between the age groups was found with headache and alterations in consciousness, more commonly seen in adults, while vomiting, ear pain was more common in children (p<0.05). Concomitant otitis, sinusitis, pneumonia, and sepsis were often observed. The mortality rate was much higher in adults (43%) when compared with children (8%)

The indoor radon and thoron concentrations in schools of Skopje (Republic of North Macedonia) and Banja Luka (Republic of Srpska) cities measured by Raduet detectors

Radon (222Rn) and thoron (220Rn) are natural radioactive gases, generated in the terrestrial materials. They are the main sources of public exposure to ionising radiation in any of indoor environment worldwide. Differences in half-lives of 222Rn (T1/2 = 3.8 d) and 220Rn (T1/2 = 55.6 s) lead to its different indoor behavior. Several studies of indoor 222Rn and 220Rn in Northern Macedonia have been performed, starting with measurements in dwellings in 2008 and continuing with measurements in schools during 2012. The surveys in the Republic of Srpska began later (in 2011) with the simultaneous 222Rn and 220Rn measurements in the dwellings and schools of Banja Luka cities. This paper, as a result of our cooperation, summarizes the results and general conclusions obtained from 222Rn and 220Rn measurements in schools of capitals. In both cities, the measurements were made using Raduet - nuclear track detectors; deployed at distances: >0.5m (Skopje) and 0.2m (Banja Luka); and exposed in a period: March 2012 - May 2012 (Skopje) and April 2011 - May 2012 (Banja Luka). Results for 222Rn and 220Rn concentrations in both cities have a log-normal distribution. The 222Rn geometric mean value of 71 Bq/m3 in Skopje is higher than in Banja Luka city (GM = 50 Bq/m3 ). Among different radon potential in the cities, this difference could be related to the different exposure time of detectors. Furthermore, the dispersion of the 222Rn results in each city expressed through geometric standard deviation is relatively low: GSD = 2.13 (Skopje) and GSD = 2.11 (Banja Luka) indicating relatively homogeneous data sets. The 220Rn concentrations in Banja Luka (GM = 51 Bq/m3 ) were higher than in Skopje (GM = 11 Bq/m3 ). It is obvious that in the case of 220Rn, the exposure period did not play a significant role. One of the reasons for this difference could be the position of the detectors as well as the different building materials in the schools. On the contrary, the dispersion of the 220Rn results in Skopje (GSD = 3.38) was greater than in Banja Luka (GSD = 2.07)

Simultaneous Determination of long-term average Fluxes of CR Muons and Solar pp-Neutrinos

The Allchar mine of southern FYR Macedonia contains the world's largest known concentration of thallium bearing minerals. LOREX (acronym for the geochemical LORandite EXperiment) is an international collaboration exploring the opportunity to use the rare mineral lorandite (TlAsS2) for the simultaneous determination of both the average cosmic ray (CR) muon flux and the average pp-solar neutrino flux, over the 4.3 million year age of the deposit. Both fluxes will be determined by counting the extremely small number of atoms of the long-lived 205 Pb present in the mineral, produced by both muons and neutrinos in the reactions with the most abundant stable isotope, 205 Tl. CR muons participate in the reaction 205 Tl(μp,n) 205 Pb, whereas the neutrinos induce the capture reaction 205 Tl(νe,e) 205 Pb*→205 Pb. Assuming a constant solar luminosity and using the currently favoured LMA WSM neutrino oscillation scenario and the estimated neutrino capture cross-section, the expected concentration of neutrinogenic 205 Pb is ~23 atoms per gram of lorandite. In contrast with the production of 205 Pb by solar neutrinos, which is independent of depth, cosmogenic 205 Pb production is strongly depth-dependent and, therefore, very sensitive to the long-term erosion history of the field area. The neutrinogenic 205 Pb component will be estimated by measuring, at the GSI, the total (neutrinogenic + muogenic) 205 Pb concentration at different depths in the Allchar mine, and extrapolating the downwards decreasing trend. The muogenic component is then obtained by subtracting the neutrinogenic, and the small depth-independent background concentration, from the total 205 Pb. The average CR muon flux is henceforth deduced by taking into account the experimentally determined erosion rate at the mining field, while the average solar neutrino flux is obtained from the knowledge of the experimentally determined neutrino capture cross section (to be hopefully measured at the GSI in near future). The best expected resolution of the proposed method is at present of the order of 30% at the 68%CL, i.e. we will be able to detect long-term departures from the modern neutrino and/or fast muon fluxes if they were bigger than 30%. Current status of this complex experiment will be discussed in some detail

Insoluble Particles in the Snowpack of the Ob River Basin (Western Siberia) a 2800 km Submeridional Profile

Snowpack exhibits properties that make it a unique natural archive of airborne pollution. The data on insoluble particles in the Ob River catchment (Western Siberia) snowpack are limited. Insoluble particles in the snowpack of Western Siberia were studied at 36 sites on a 2800 km submeridional profile from the city of Barnaul to Salekhard in February 2020. Snow samples were collected over the full depth of the snow core, from the surface of the snow cover to the boundary with soil, except for the lower 1–2 cm. After the filtration of melted snow through a 0.45-µm membrane, the particle composition was studied using a scanning electron microscope with an energy microprobe. In the background areas, the concentration of insoluble particles in the snow was below 2 mg/L. Significantly higher particle concentrations were encountered near cities and hydrocarbon production areas. Particulate matter in snow mainly consists of biogenic and lithogenic particles mixed with anthropogenic particles (ash and black carbon aggregates). The proportion of anthropogenic particles increases near cities and areas of active hydrocarbon production

Status and new data of the geochemical determination pp-neutrino flux by LOREX

LOREX, the acronym of LORandite EXperiment, is the only long-time solar neutrino experiment still actively pursued. It addresses the long-time detection of the solar neutrino flux with the thallium-bearing mineral lorandite, TlAsS2 from the mine of Allchar, FYR Mazedonia, via the neutrino-capture reaction

Status of the geochemical determination of the solar pp-neutrino flux by LOREX

LOREX, the acronym for LORandite EXperiment, is the only geochemical solar neutrino experiment still actively pursued. It addresses the determination of the long-time average of the solar neutrino flux with the thallium-bearing mineral lorandite, TlAsS2, from the mine of Allchar, FYR Macedonia, via the neutrino-capture reaction 205Tl + ν(e) → 205Pb + e-. The final step of LOREX would be the extraction of lorandite and the quantitative determination of the ratio of 205Pb / 205Tl atoms, thus providing the product of solar neutrino flux and neutrino-capture cross section, integrated over the age of lorandite of 4.31 ∙ 10^6 yr. Moreover, the detector offers the lowest threshold among all the detectors of only 52 keV for solar ppneutrinos. This paper presents new data on accurate geological age of the minerals at Allchar, as well as the recent results for erosion rates at two lorandite rich locations. These are based on Accelerator Mass Spectrometry (AMS) determination of 10Be, 26Al and 53Mn in characteristic samples and on the independent geomorphological investigations. Reliable erosion rates are of paramount importance for the proper determination of background of 205Pb induced by cosmic-ray muons. Provided that these satisfactorily high values of erosion rates are corroborated by more measurements of additional probes, the experiment is expected to reach an acceptable signal-to-background ratio. Finally, it is discussed how to obtain the still unknown capture probability of solar pp-neutrinos from 205Tl into 205Pb via the measurement of the lifetime for the bound beta decay of the completely ionised 205Tl, as well as how to count by Schottky mass spectrometry the extremely small number of 205Pb atoms found within the few kilograms of the mineral, needed to attain the accuracy of the final result of the order of some 30%. Both crucial measurements are planned to be carried out at the GSI