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During the 2019 Leonid meteor shower, the European Fireball Network recorded a bright fireball (meteor code: EN171119_041459) at 04:15:0.2 (UT) on 17 November 2019. The fireball appeared at coordinates 49.95°N 15.56°E at the height of 134.46 km, and disappeared at coordinates 50.23°N 15.26°E and at the height of 71.81 km. The ionization effect caused by the fireball appeared in the digisonde’s campaign measurements taken with a 2 ionogram/min time resolution at Průhonice station (50.00°N, 14.60°E). The trace appeared on the ionograms as a faint sporadic E-like layer, and the maximum ionization reached the upper limit of the measurement, 17 MHz. The trace persisted for 20 min on the ionograms, first appearing at 04:15:40 (UT) and finally disappearing at 04:35:40 (UT). The virtual height of the trace according to the ionograms appeared between 114 and 142 km, first it descended and then it ascended. Drift measurements were also taken with the digisonde every minute. Between 04:19:20 and 04:35:20 (UT), between altitudes of 122–142 km, 1-5 reflections were recorded on most SkyMaps. In addition, the Continuous Doppler Sounding developed by the Institute of Atmospheric Physics CAS also recorded the ionization signature of the fireball between 04:18 and 04:30 (UT) on 2 of the 3 sounding paths operating at 4.65 MHz. This is the first evidence that the plasma trail of a documented fireball can be detected by a DPS-4D digisonde (not only on ionograms, but also by drift measurements) and by the Continuous Doppler Sounding system.

A multi-instrumental analysis of the meridional ionospheric response is presented over Europe during the two largest ICME-driven geomagnetic storms of solar cycle #24 maximum. Data from 5 European digisonde stations, ground-based Global Navigation Satellite System, Total Electron Content (GNSS TEC), the ratio of the TEC difference (rTEC), as well as Swarm and Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) satellite observations have been used for the investigation of selected intervals (11–17 November, 2012, and 16–25 March, 2015). The storm evolution is monitored by digisonde foF2 critical frequency (related to the maximum electron density of F2-layer) and GNSS TEC data. Moreover, Global Ultraviolet Imager (GUVI) measurements from the TIMED satellite are used to investigate the changes in the thermospheric O/N2 ratio. Our main focus was on the main phase of the geomagnetic storms, when during the nighttime hours extremely depleted plasma was detected. The extreme depletion is observed in foF2, TEC and rTEC, which is found to be directly connected to the equatorward motion of the midlatitude ionospheric trough (MIT) on the nightside. We demonstrate a method (beside the existing ones) which allows the monitoring of the storm-time evolution of the disturbances (e.g., MIT, SAPS, SED) in the thermosphere-ionosphere-plasmasphere system by the combined analysis of the worldwide digisonde system data (with the drift measurements and the ionospheric layer parameters with 5–15 min cadence), with rTEC and GNSS TEC data, and with the satellite data like Swarm, TIMED/GUVI.

In 2003, a decreasing trend was reported in the long-term (1962–2001) fair weather atmospheric electric potential gradient (PG) measured in the Széchenyi István Geophysical Observatory (NCK; 47∘38′ N, 16∘43′ E), Hungary, Central Europe. The origin of this reduction has been the subject of a long-standing debate, due to a group of trees near the measurement site which reached significant height since the measurements have started. Those trees have contributed to the lowering of the ambient vertical electric field due to their electrostatic shielding effect. In the present study, we attempt to reconstruct the true long-term variation of the vertical atmospheric electric field at NCK. The time-dependent shielding effect of trees at the measurement site was calculated to remove the corresponding bias from the recorded time series. A numerical model based on electrostatic theory was set up to take into account the electrostatic shielding of the local environment. The validity of the model was verified by on-site measurement campaigns. The changing height of the trees between 1962 and 2017 was derived from national-average age–height diagrams for each year. Modelling the time-dependent electrical shielding effect of the trees at NCK revealed that local effects played a pivotal role in the long-term decrease. The results suggest that earlier attempts could not quantify the shielding effect of the trees at NCK accurately. In this work it is found that the reconstructed PG time series at NCK exhibits an increase between 1962 and 1997 followed by a decaying trend since 1997. It is pointed out that long-term variation in summertime and wintertime PG averages should be analysed separately as these may contribute to trends in the annual mean values rather differently.

The Széchenyi István Geophysical Observatory, also known as the Nagycenk Geophysical Observatory (NCK), was established in 1957. It has been the only measurement site in Hungary where observations of various parameters of the atmospheric global electric circuit are made in the framework of organized research under the umbrella of the Hungarian Academy of Sciences (MTA). Measurements of the atmospheric electrical potential gradient (PG) and Schumann resonances (SRs) running quasi-continuously in the observatory for decades provide an invaluable source of information for geophysical research. This paper gives an overview on the history of the observatory and particularly on various atmospheric electricity (AE) measurements on-site to commemorate the efforts and excellence of the people who served atmospheric sciences by dedicating their lives to obtaining high-quality, reliable data and scientific achievements at the highest possible level.

We have investigated the solar flare effects on ionospheric absorption with the systematic analysis of ionograms measured at midlatitude and low-latitude ionosonde stations under different solar zenith angles. The lowest recorded ionosonde echo, the minimum frequency (fmin, a qualitative proxy for the “nondeviative” radio wave absorption occurring in the D-layer), and the dfmin parameter (difference between the value of the fmin and the mean fmin for reference days) have been considered. Data were provided by meridionally distributed ionosonde stations in Europe and South Africa during eight X- and M-class solar flares in solar cycle 23. Total and partial radio fade-out was experienced at every ionospheric station during intense solar flares (> M6). The duration of the total radio fade-out varied between 15 and 150 min and it was highly dependent on the solar zenith angle of the ionospheric stations. Furthermore, a solar-zenith-angle-dependent enhancement of the fmin (2–9 MHz) and dfmin (1–8 MHz) parameters was observed at almost every station. The fmin and dfmin parameters show an increasing trend with the enhancement of the X-ray flux. Based on our results, the dfmin parameter is a good qualitative measure for the relative variation of the “nondeviative” absorption, especially in the case of the less intense solar flares, which do not cause total radio fade-out in the ionosphere (class M6).

The level of psychological stress in children and adolescents has increased rapidly over the past decade. The aim of the present meta-analysis was to evaluate the effectiveness of school-based intervention programs targeting stress management and coping/resilience in school-aged children. The present study used more rigorous selection criteria than previous meta-analyses by only including randomized controlled trials to increase the validity of the meta-analysis. Fifty-five studies were selected for the analysis, including 66 comparisons in the case of stress and 47 comparisons in the case of coping/resilience outcomes. A meta-regression with robust variance estimation was used. Effects were calculated as the standardized mean difference (Hedges' g) between the intervention and control conditions at posttest. The results highlighted important methodological issues and the influence of outliers. Without outliers, the results indicated a small significant overall effect on stress (g = -0.15, p < .01) and coping/resilience (g = 0.14, p = .01). When outliers were included, the effect sizes markedly increased in both cases (g stress  = -0.26, p = .022; g coping/resilience  = 0.30, p = .009). Stress management interventions were more effective if they were delivered by mental health professionals or researchers than by teachers. Coping/resilience interventions were more effective in older age groups, in selective samples, and if they included cognitive behavioral therapy. An explanation of the results and a detailed discussion of the limitations of the study and its implications for practice are considered., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Survival and hospitalization are critically important outcomes considered when choosing between intensive hemodialysis (HD), conventional HD, and peritoneal dialysis (PD). However, the comparative effectiveness of these modalities is unclear., Objective: We had the following aims: (1) to compare the association of mortality and hospitalization in patients undergoing intensive HD, compared with conventional HD or PD and (2) to appraise the methodological quality of the supporting evidence., Data Sources: MEDLINE, Embase, ISI Web of Science, CENTRAL, and nephrology conference abstracts., Study Eligibility Participants and Interventions: We included cohort studies with comparator arm, and randomized controlled trials (RCTs) with >50% of adult patients (≥18 years) comparing any form of intensive HD (>4 sessions/wk or >5.5 h/session) with any form of chronic dialysis (PD, HD ≤4 sessions/wk or ≤5.5 h/session), that reported at least 1 predefined outcome (mortality or hospitalization)., Methods: We used the GRADE approach to systematic reviews and quality appraisal. Two reviewers screened citations and full-text articles, and extracted study-level data independently, with discrepancies resolved by consensus. We pooled effect estimates of randomized and observational studies separately using generic inverse variance with random effects models, and used fixed-effects models when only 2 studies were available for pooling. Predefined subgroups for the intensive HD cohorts were classified by nocturnal versus short daily HD and home versus in-center HD., Results: Twenty-three studies with a total of 70 506 patients were included. Of the observational studies, compared with PD, intensive HD had a significantly lower mortality risk (hazard ratio [HR]: 0.67; 95% confidence interval [CI]: 0.53-0.84; I 2 = 91%). Compared with conventional HD, home nocturnal (HR: 0.46; 95% CI: 0.38-0.55; I 2 = 0%), in-center nocturnal (HR: 0.73; 95% CI: 0.60-0.90; I 2 = 57%) and home short daily (HR: 0.54; 95% CI: 0.31-0.95; I 2 = 82%) intensive regimens had lower mortality. Of the 2 RCTs assessing mortality, in-center short daily HD had lower mortality (HR: 0.54; 95% CI: 0.31-0.93), while home nocturnal HD had higher mortality (HR: 3.88; 95% CI: 1.27-11.79) in long-term observational follow-up. Hospitalization days per patient-year (mean difference: -1.98; 95% CI: -2.37 to -1.59; I 2 = 6%) were lower in nocturnal compared with conventional HD. Quality of evidence was similarly low or very low in RCTs (due to imprecision) and observational studies (due to residual confounding and selection bias)., Limitations: The overall quality of evidence was low or very low for critical outcomes. Outcomes such as quality of life, transplantation, and vascular access outcomes were not included in our review., Conclusions: Intensive HD regimens may be associated with reduced mortality and hospitalization compared with conventional HD or PD. As the quality of supporting evidence is low, patients who place a high value on survival must be adequately advised and counseled of risks and benefits when choosing intensive dialysis. Practice guidelines that promote shared decision-making are likely to be helpful., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background. Pregnancy occurs among 1-7% of women on chronic dialysis. Experience regarding pregnancy and dialysis originates from anecdotal reports, case series and surveys. This survey updates the US nephrologists' experience with pregnancy on hemodialysis (HD) over the past 5 years. We evaluated maternal and fetal outcomes, certain practice patterns such as dialysis regimens utilized and nephrologist knowledge and comfort level when caring for a pregnant patient on HD. Methods. An anonymous Internet-based 23-question survey was e-mailed to end-stage renal disease Networks of America program directors for forwarding to practicing nephrologists. Results. A total of 196 nephrologists responded to the survey, reporting >187 pregnancies. Of the respondents, 45% had cared for pregnant females on HD and 78% of pregnancies resulted in live births. In 44% of the pregnancies a diagnosis of preeclampsia was made. There were no maternal deaths. Nephrologists most commonly prescribe 4-4.5 h of HD 6 days/week for pregnant women on dialysis. Women dialyzed cumulatively for >20 h/week were 2.2 times more likely to develop preeclampsia than those who received ≤20 h of HD per week. Conclusion. Providing intensive HD is a common treatment approach when dialyzing pregnant women. Maternal and fetal outcomes can be improved. There is a trend toward better live birthrates with more intense HD. Whether more cumulative hours of dialysis per week increases the risk of preeclampsia needs to be further investigated.

A new series of beta amino acids, which act as CXCR3 antagonists, has been identified. The formerly optimized N,N-disubstituted benzylamine derivatives with carboxylic acid function on the N-atom was used as starting point and compounds with carboxyl function not attached to the N-atom were investigated. Affinity, metabolic stability in human and mouse liver microsomes and Caco-2 permeability were optimized. Compounds with double-digit nanomolar CXCR3 affinity, favourable microsomal stability and Caco-2 permeability have been identified., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

N,N-Disubstituted benzylamine derivatives have been identified as CXCR3 antagonists. Compounds were optimized to improve affinity and selectivity, to increase metabolic stability in human and mouse liver microsomes, to increase Caco-2 permeability. Optimization was supported by monitoring physico-chemical properties using both experimental and computational means. Several compounds with double-digit nanomolar CXCR3 affinity, favorable selectivity, microsomal stability, Caco-2 permeability and human hepatocyte clearance have been identified., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Optimum conditions for chicken (Gallus gallus) lymphocyte transformation tests were determined. Thrice-washed chicken buffy-coat cells obtained after slow centrifugation (40 x g for 10 minutes) responded substantially better to mitogenic stimulation than lymphocytes isolated on separation media containing Ficoll. Maximum responses were obtained with 2 x 10(7) lymphoid cells/ml. Responses to the mitogens were greatest when fetal bovine serum was used at a 5% concentration or pooled chicken serum and autologous plasma were used at a 1.25% concentration. Optimum mitogen concentrations varied with individual birds, timing of the culture, temperature of incubation, and serum concentration in the cultures. When 1.25% chicken serum was used in the cultures, responses were usually greatest with final concentrations of 30-50 micrograms/ml of concanavalin A (Con A) and 30-50 micrograms/ml of phytohemagglutinin-P (PHA-P). The optimum concentration of pokeweed mitogen (PWM) varied from 1 to 40 micrograms/ml among the birds and was practically impossible to establish in general. The incubation in humidified air with 5% CO2 was significantly better at 40 C than at 37 C. The total culture time of 40 hours including pulsing with 3H-thymidine during the final 16 hours of incubation was the best for Con A- and PHA-P-stimulated cells, whereas a longer incubation of 64 hours gave the highest results with PWM stimulations.

Optimum conditions for turkey lymphocyte transformation tests were determined. Thrice-washed turkey buffy-coat cells obtained after slow centrifugation (40 x g, 10 minutes) responded well to mitogenic stimulation. Turkey lymphocytes isolated on Ficoll-containing separation media largely lost their ability to respond to mitogens. Maximum responses were obtained with 2 x 10(7) lymphoid cells/ml. Responses to the mitogens were greatest when bovine fetal serum was used at a 2.5% concentration or pooled turkey serum and autologous plasma were used at a 1.25% concentration. Higher concentrations of turkey serum or plasma decreased the responses when sub-optimum doses of concanavalin-A (Con A) or phytohemagglutinin-P (PHA-P) were used. Serum-free cultures gave higher stimulation indices than cultures with serum only when sub-optimum doses of Con A or PHA-P were used. Optimum mitogen concentrations varied with individual birds, timing of the culture, temperature of incubation, and serum concentration in the cultures. Responses were usually greatest with final concentrations of 5 micrograms Con A/ml, 10 micrograms PHA-P/ml, and 20 micrograms pokeweed mitogen (PWM)/ml and when the cultures were incubated in 96-well microplates at 40 C in humidified air with 5% CO2 for 40-42 hours with pulsing with 3H-thymidine during the final 16 hours of incubation.

Two avian and seven mammalian cell lines were evaluated for their application in propagating avian reovirus WVU 2937. Cultures were compared for monolayer-formation time, support of viral replication, passages and postinfection time required for expression of cytopathic effect (CPE), type of CPE, and virus yield. CPE was observed on the first passage with infected egg yolk in primary chicken embryo kidney cells, primary through tertiary chicken embryo liver (CEL) cells, and African green monkey kidney (VERO) cells; on the third blind passage of infected supernatant in Georgia bovine kidney cells, Crandall feline kidney cells, and baby hamster cells; on the fifth blind passage in rabbit kidney cells; and on the tenth blind passage in porcine kidney cells. CPE was not observed after 10 viral passages in rabbit bone-marrow cells. Monolayer formation time and postinfection time for CPE expression occurred sooner, and virus yield was greater, with CEL and VERO cells than with other cell lines.

The effect of pH, ionic strength, cation concentration, ethylenediaminetetraacetic acid trisodium salt (Na3EDTA), time and temperature were studied to determine the optimal conditions for titrating the hemolytic complement (C) activity in sera of chicken (Gallus gallus). Swine erythrocytes (E) sensitized with rabbit antibodies were the most sensitive, while chicken serum had a smaller amount of "natural" antibody against them than against red blood cells from other five species tested. The highest titers of chicken C, when tested with swine sensitized E, were detected when isotonic NaCl-barbital buffer was used as diluent, having the ionic strength of 0.15, conductance of 11 millimhos/cm at 20 degrees C. However, maximal chicken C titers detected with sensitized rabbit E were obtained at ionic strength of 0.07 to 0.11 depending on pH. A final concentration of 1 X 10(-3) M of Mg2+ and 3 X 10(-4) M of Ca2+ and pH 8 were optimal in both cases. The temperature of 30 degrees C and time of 60 minutes were appropriate to reveal the maximal titers..

A simple method for preparation of highly specific antisera against equine infectious anemia virus proteins p26 and p16 is described. Viral proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The motility of the viral proteins in the gel was compared with standards. Unstained portions of the slab gel were sliced into 5-mm bands, emulsified with Freund's complete adjuvant, and injected into rabbits to produce specific antisera.