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1.
Physiol Plant ; 174(4): e13733, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35699602

RESUMO

The influence of solar activity on plant growth has been studied for over 100 years, however, this phenomenon is still poorly understood on a daily scale. The data from extensive monitoring of the growth of peat moss Sphagnum riparium, which we are conducting in the mires of Karelia (Russia), may shed light on this issue. During the 6 years of observation, 161,190 shoots were measured, and 1075 growth rates were obtained. Considering together the growth rates with the sunspot number and involving data on seasonal temperature, we found previously unknown effects of daily-scale solar activity on plant growth. It was found that the sunspot number weakly but significantly inhibits the growth of Sphagnum. The extreme sunspot number in the 4 days before the growth rate values have a stronger influence. The involvement of temperature data showed that inhibition in growth is observed only in the temperature range from 6.7°C to 15.3°C and disappears beyond these limits. In addition, the data obtained showed that the influence of sunspot number on the growth of Sphagnum is progressively increasing along the gradient from the minimum to the maximum of the 11-year solar cycle. The study provides one of the first results on the effect of solar activity on plant growth on a daily scale. The results expand our knowledge of the biological effects of solar activity. Indirectly, they can also be useful to better our understanding of the ozone layer's involvement in this process.


Assuntos
Atividade Solar , Sphagnopsida , Desenvolvimento Vegetal , Federação Russa , Sphagnopsida/crescimento & desenvolvimento , Temperatura
2.
Sci Rep ; 12(1): 7631, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538243

RESUMO

The direct interaction between large-scale interplanetary disturbances emitted from the Sun and the Earth's magnetosphere can lead to geomagnetic storms representing the most severe space weather events. In general, the geomagnetic activity is measured by the Dst index. Consequently, its accurate prediction represents one of the main subjects in space weather studies. In this scenario, we try to predict the Dst index during quiet and disturbed geomagnetic conditions using the interplanetary magnetic field and the solar wind parameters. To accomplish this task, we analyzed the response of a newly developed neural network using interplanetary parameters as inputs. We strongly demonstrated that the training procedure strictly changes the capability of giving correct forecasting of stormy and disturbed geomagnetic periods. Indeed, the strategy proposed for creating datasets for training and validation plays a fundamental role in guaranteeing good performances of the proposed neural network architecture.


Assuntos
Atividade Solar , Tempo (Meteorologia) , Humanos , Campos Magnéticos , Redes Neurais de Computação , Vento
3.
Environ Res ; 212(Pt C): 113435, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35580666

RESUMO

Solar radiation is the external driving force of the Earth's climate system. In different spatial and temporal scales, meteorological elements have different responses and lag periods to solar activity (SA), climatic oscillation (CO), geographic factors (GF) and other influencing factors. However, such studies are not abundant and in-depth in the world. To further understand the "solar-climate-water resource" system, this study considers China as the study area and investigates the monthly data of temperature (T) and precipitation (P) during 1900-2020 that were obtained from 3836 grid stations. The strong interaction and lag distribution between T or P with SA and CO were studied and influence weights of SA, CO, and geographical factors (GF) of each grid station were calculated. A multivariate hysteretic decomposition model was established to simulate and quantitatively decompose the periodic lag considering the factors of the earth's revolution. It is found that the strong interaction/lag periods obtained in a long-time scale can be decomposed into several periods shorter than the SA period. The distribution of strong interaction/lag periods is nested with topography and echoes with cities. The underlying surface conditions and urbanization are also important factors affecting the T and P lag. There are two distinct dividing lines in the lag period and influencing factor pattern of T and P. The T dividing line moves through valleys where water or mountain ranges meet, where the gap facilitates monsoon movement across regions, while the P dividing line is a zone of dramatic terrain, where tall mountains block water vapor transport. In the lag trend of T, the northern region of China has the longest lag period, and the lag period of surrounding regions tends to converge to the northern region. The lag period caused by SN in southwest China is larger than that in northwest China, while the lag effect of CO is opposite in the above two regions. The lag trend of P also has the above characteristics, but the difference is that the lag period in central China is the longest.


Assuntos
Clima , Atividade Solar , China , Cidades , Mudança Climática , Temperatura
4.
Nat Commun ; 13(1): 1196, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35256613

RESUMO

The Sun sporadically produces eruptive events leading to intense fluxes of solar energetic particles (SEPs) that dramatically disrupt the near-Earth radiation environment. Such events have been directly studied for the last decades but little is known about the occurrence and magnitude of rare, extreme SEP events. Presently, a few events that produced measurable signals in cosmogenic radionuclides such as 14C, 10Be and 36Cl have been found. Analyzing annual 14C concentrations in tree-rings from Switzerland, Germany, Ireland, Russia, and the USA we discovered two spikes in atmospheric 14C occurring in 7176 and 5259 BCE. The ~2% increases of atmospheric 14C recorded for both events exceed all previously known 14C peaks but after correction for the geomagnetic field, they are comparable to the largest event of this type discovered so far at 775 CE. These strong events serve as accurate time markers for the synchronization with floating tree-ring and ice core records and provide critical information on the previous occurrence of extreme solar events which may threaten modern infrastructure.


Assuntos
Prótons , Atividade Solar , Planeta Terra , Alemanha , Árvores
5.
Bull Exp Biol Med ; 172(5): 561-565, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35348958

RESUMO

The dynamics of proliferative activity of the L-929 cell culture of mouse fibroblast-like cells in the phase of logarithmic growth was compared with some heliogeophysical parameters (Ap and ULF indexes of geomagnetic activity, vertical component of the interplanetary magnetic field, and intensity of fluctuations of secondary cosmic radiation estimated by the neutron monitoring near the Earth's surface). Among the considered heliogeophysical parameters, only the magnitude of fluctuations of minute-to-minute changes in the neutron monitor indicator reliably and negatively correlates with the rate of cell culture reproduction. Considering that the amplitude of secondary cosmic fluctuations is about 5%, which is 0.1% of the total ray flux, and proliferative activity varies in the range of 30-50%, the probability of a direct biotrophic effect of this physical factor is extremely low. It seems likely that proliferative activity of L-929 cell culture is directly affected by another environmental factor, the marker of which is the intensity of neutron counting rate fluctuations.


Assuntos
Radiação Cósmica , Animais , Campos Magnéticos , Camundongos , Nêutrons , Atividade Solar
6.
Life Sci Space Res (Amst) ; 32: 79-95, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35065765

RESUMO

At present, human spaceflight is confined to low Earth orbit but, in future, will again go to the Moon and, beyond, to Mars. The provision of food during these extended missions will need to meet the special nutritional and psychosocial needs of the crew. Terrestrially grown and processed food products, currently provided for consumption by astronauts/cosmonauts, have not yet been systematically optimised to maintain their nutritional integrity and reach the shelf-life necessary for extended space voyages. Notably, space food provisions for Mars exploration will be subject to extended exposure to galactic cosmic radiation and solar particle events, the impact of which is not fully understood. In this review, we provide a summary of the existing knowledge about current space food products, the impact of radiation and storage on food composition, the identification of radiolytic biomarkers and identify gaps in our knowledge that are specific in relation to the effect of the cosmic radiation on food in space.


Assuntos
Radiação Cósmica , Voo Espacial , Astronautas , Radiação Cósmica/efeitos adversos , Humanos , Lua , Atividade Solar
7.
J Am Heart Assoc ; 10(21): e021006, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34713707

RESUMO

Background Since solar activity and related geomagnetic disturbances modulate autonomic nervous system activity, we hypothesized that these events would be associated with blood pressure (BP). Methods and Results We studied 675 elderly men from the Normative Aging Study (Boston, MA) with 1949 BP measurements between 2000 and 2017. Mixed-effects regression models were used to investigate the association of average 1-day (ie, day of BP measurement) to 28-day interplanetary magnetic field intensity, sunspot number, and a dichotomized measure of global geomagnetic activity (Kp index) in 4-day increments with diastolic and systolic BP. We adjusted for meteorological conditions and other covariates associated with BP, and in additional models adjusted for ambient air pollutants (particulate matter with an aerodynamic diameter ≤2.5 µm, black carbon, and particle number) and ambient particle radioactivity. There were positive associations between interplanetary magnetic field, sunspot number, and Kp index and BP that were greatest with these exposures averaged over 16 through 28 days before BP measurement. An interquartile range increase of 16-day interplanetary magnetic field and sunspot number and higher Kp index were associated with a 2.5 (95% CI, 1.7‒3.2), 2.8 (95% CI, 2.1‒3.4), and 1.7 (95% CI, 0.8‒2.5) mm Hg increase, respectively, for diastolic BP as well as a 2.1 (95% CI, 0.7‒3.6), 2.7 (95% CI, 1.5‒4.0), and 0.4 (95% CI, -1.2 to 2.1) mm Hg increase, respectively, for systolic BP. Associations remained after adjustment for ambient air pollutants and ambient particle radioactivity. Conclusions Solar activity and solar-driven geomagnetic disturbances were positively associated with BP, suggesting that these natural phenomena influence BP in elderly men.


Assuntos
Atividade Solar , Idoso , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pressão Sanguínea , Exposição Ambiental , Humanos , Masculino , Material Particulado/análise
8.
Life Sci Space Res (Amst) ; 31: 1-13, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34689941

RESUMO

The diverse near-Earth radiation environment due to cosmic rays and solar radiation has direct impact on human civilization. In the present and upcoming era of increasing air transfer, it is important to have precise idea of radiation dose effects on human body during air travel. Here, we calculate the radiation dose on the human body at the aviation altitude, also considering the shielding effect of the aircraft structure, using Monte Carlo simulation technique based on Geant4 toolkit. We consider proper 3D mathematical model of the atmosphere and geomagnetic field, updated profile of the incoming particle flux due to cosmic rays and appropriate physics processes. We use quasi-realistic computational phantoms to replicate the human body (male/female) for the effective dose calculation and develop a simplified mathematical model of the aircraft (taking Boeing 777-200LR as reference) for the shielding study. We simulate the radiation environment at the flying altitude (at 10 km and considering geomagnetic latitude in the range of 45-50°), as well as at various locations inside the fuselage of the aircraft. Then, we calculate the dose rates in the different organs for both male and female phantoms, based on latest recommendations of International Commission on Radio logical Protection. This calculation shows that the sex-averaged effective dose rate in human phantom is 5.46 µSv/h, whereas, if we calculate weighted sum of equivalent dose contributions separately in female and male body: total weighted sum of equivalent dose rate received by the female phantom is 5.72 µSv/h and that by the male phantom is 5.20 µSv/h. From the simulation, we also calculate the numerous cosmogenic radionuclides produced inside the phantoms through activation or spallation processes which may induce long-term biological effects.


Assuntos
Aviação , Radiação Cósmica , Exposição Ocupacional , Monitoramento de Radiação , Altitude , Radiação Cósmica/efeitos adversos , Feminino , Corpo Humano , Humanos , Masculino , Método de Monte Carlo , Doses de Radiação , Atividade Solar
9.
Life Sci Space Res (Amst) ; 30: 66-71, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34281666

RESUMO

The problem of full-scale ground-based modeling of cosmic radiation on heavy-ion accelerators for space radiobiology is very urgent. A new type of space radiation simulator at the 56Fe ion beam with energy 1 GeV/n is proposed. The simulator uses rotating converters consisting of segmented targets with varying thicknesses. When a flat uniform field of primary 56Fe ions is used, this design ensures the uniformity of the fields of all secondary particles behind the targets. The proposed setup with four replaceable converters makes it possible to simulate not only the distribution of linear energy transfers of cosmic radiation but also reproduce continuous energy spectra of all charged fragments of the projectile ion from protons to Co. The results of simulation of the internal radiation field inside the habitable module of a spacecraft with a shell of 15 g/cm2 Al, generated by particles of galactic cosmic rays in the solar activity range from 0 to 190 Wolf numbers, are presented.


Assuntos
Radiação Cósmica , Voo Espacial , Transferência Linear de Energia , Radiobiologia , Atividade Solar , Astronave
10.
Sensors (Basel) ; 21(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34300557

RESUMO

This paper evaluates variations in solar activity and their impact on the human nervous system, including the manner in which human behavior and decision-making reflect such effects in the context of (symmetrical) social interactions. The relevant research showed that solar activity, manifesting itself through the exposure of the Earth to charged particles from the Sun, affects heart variability. The evaluation methods focused on examining the relationships between selected psychophysiological data and solar activity, which generally causes major alterations in the low-level electromagnetic field. The investigation within this paper revealed that low-level EMF changes are among the factors affecting heart rate variability and, thus, also variations at the spectral level of the rate, in the VLF, (f = 0.01-0.04 Hz), LF (f = 0.04-0.15 Hz), and HF (f = 0.15 az 0.40 Hz) bands. The results of the presented experiments can also be interpreted as an indirect explanation of sudden deaths and heart failures.


Assuntos
Eletrocardiografia , Insuficiência Cardíaca , Coração , Frequência Cardíaca , Humanos , Atividade Solar
11.
Environ Res ; 201: 111532, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34166658

RESUMO

Solar radiation plays a major role in atmospheric photochemistry, contributing to the formation and growth of ultrafine particles (PN). PN affect global Earth's radiation balance, climate system, and human health. However, the impact of solar activity on ambient PN remains unclear. In this study, we investigated the associations between daily ambient PN concentrations [particle number (PN)/cm3] and solar radio flux [solar activity index (F10.7 in sfu)] as a solar activity parameter, shortwave solar radiation (SWR), daylight time (DL), cosmic ray-induced ionization (CRII), and air pollution [PM2.5, black carbon (BC) and SO2] over a 19-year period in Boston, MA. We used generalized additive models adjusted for local environmental conditions. We found that F10.7 was the strongest predictor for daily PN concentrations over all time lags (0-28 days of lags) and seasons. The effects were higher in winter and fall. In winter, an interquartile (IQR) of 60 sfu F10.7 corresponded to an increase of 5770 PN/cm3 in the day of PN collection. In fall, an IQR of 75.5 sfu F10.7 was associated with an increase of 5429 PN/cm3. The effects of F10.7 on PN concentrations were slightly greater when the models were adjusted for air pollution. In summer, ambient PN concentrations were statistically significantly associated with F10.7, SWR, and BC, with the strongest association found for PN and BC in the day of PN collection. Unlike the effects of F10.7, SWR and local pollutants on PN concentrations, DL and CRII were negatively associated with ambient PN in the analyses. These findings suggest that solar activity may have a significant impact on daily ambient PN concentrations that affect the Earth's climate system and human health.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Boston , Humanos , Material Particulado/análise , Atividade Solar
12.
Artigo em Inglês | MEDLINE | ID: mdl-33902387

RESUMO

Staying longer in outer space will inevitably increase the health risks of astronauts due to the exposures to galactic cosmic rays and solar particle events. Exposure may pose a significant hazard to space flight crews not only during the mission but also later, when slow-developing adverse effects could finally become apparent. The body of literature examining ground-based outcomes in response to high-energy charged-particle radiation suggests differential effects in response to different particles and energies. Numerous animal and cellular models have repeatedly demonstrated the negative effects of high-energy charged-particle on the brain and cognitive function. However, research on the role of space radiation in potentiating cardiovascular dysfunction is still in its early stages. This review summarizes the available data from studies using ground-based animal models to evaluate the response of the brain and heart to the high-energy charged particles of GCR and SPE, addresses potential sex differences in these effects, and aims to highlight gaps in the current literature for future study.


Assuntos
Encéfalo/efeitos da radiação , Sistema Cardiovascular/efeitos da radiação , Radiação Cósmica , Exposição à Radiação/estatística & dados numéricos , Voo Espacial , Astronautas , Cognição , Meio Ambiente Extraterreno , Feminino , Humanos , Masculino , Proteção Radiológica , Atividade Solar
13.
Artigo em Inglês | MEDLINE | ID: mdl-33902391

RESUMO

Both microgravity and radiation exposure in the spaceflight environment have been identified as hazards to astronaut health and performance. Substantial study has been focused on understanding the biology and risks associated with prolonged exposure to microgravity, and the hazards presented by radiation from galactic cosmic rays (GCR) and solar particle events (SPEs) outside of low earth orbit (LEO). To date, the majority of the ground-based analogues (e.g., rodent or cell culture studies) that investigate the biology of and risks associated with spaceflight hazards will focus on an individual hazard in isolation. However, astronauts will face these challenges simultaneously Combined hazard studies are necessary for understanding the risks astronauts face as they travel outside of LEO, and are also critical for countermeasure development. The focus of this review is to describe biologic and functional outcomes from ground-based analogue models for microgravity and radiation, specifically highlighting the combined effects of radiation and reduced weight-bearing from rodent ground-based tail suspension via hind limb unloading (HLU) and partial weight-bearing (PWB) models, although in vitro and spaceflight results are discussed as appropriate. The review focuses on the skeletal, ocular, central nervous system (CNS), cardiovascular, and stem cells responses.


Assuntos
Astronautas , Radiação Cósmica , Exposição à Radiação , Voo Espacial , Ausência de Peso , Elevação dos Membros Posteriores , Humanos , Atividade Solar , Suporte de Carga
14.
Life Sci Space Res (Amst) ; 29: 53-62, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33888288

RESUMO

In April 2001, Mars Odyssey spacecraft with the High Energy Neutron Detector (HEND) onboard was launched to Mars. HEND/Odyssey was switched on measurement mode for most of transit to Mars to monitor variations of spacecraft background and solar activity. Although HEND/Odyssey was originally designed to measure Martian neutron albedo and to search for Martian subsurface water/water ice, its measurements during cruise phase to Mars are applicable to evaluate spacecraft ambient radiation background. The biological impact of the neutron component of this radiation background should be understood, as it must be taken into account in planning future human missions to Mars. We have modeled the spacecraft neutron spectral density and compared it with HEND measurements to estimate neutron dose equivalent rates during Odyssey cruise phase, which occurred during the maximum period of solar cycle 23. We find that the Odyssey ambient neutron environment during May - September 2001 yields 10.6 ± 2.0 µSv per day in the energy range from 0 to 15 MeV, and about 29 µSv per day when extrapolated to the 0-1000 MeV energy range during solar quiet time (intervals without Solar Particle Events, SPEs). We have also extrapolated HEND/Odyssey measurements to different periods of solar cycle and find that during solar minimum (maximum of GCR flux), the neutron dose equivalent rate during cruise to Mars could be as high as 52 µSv per day with the same shielding. These values are in good agreement with results reported for a similar measurement made with an instrument aboard the Mars Science Laboratory during its cruise to Mars in 2011-2012.


Assuntos
Radiação Cósmica , Marte , Monitoramento de Radiação , Meio Ambiente Extraterreno , Humanos , Nêutrons , Doses de Radiação , Atividade Solar , Astronave
15.
PLoS One ; 16(4): e0250785, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33905449

RESUMO

In the 1920s, during the first archaeological excavations at Uaxactún, Petén, Guatemala, an architectural complex named Group E was interpreted as an ancient Maya astronomical observatory, intended specifically for sighting the equinoctial and solstitial sunrises. In the following decades, a large number of architectural compounds with the same configuration have been found, most of them in the central lowlands of the Yucatan peninsula. The multiple hypotheses that have been proposed about the astronomical function of these complexes, commonly designated as E Groups, range from those attributing them a paramount role in astronomical observations to those that consider them merely allegorical or commemorative allusions to celestial cycles, without any observational use. This study, based on quantitative analyses of a reasonably large sample of alignment data, as well as on contextual evidence, shows that many of the previous hypotheses cannot be sustained. I argue that E Groups, although built primarily for ritual purposes, were astronomically functional, but also that they had no specific or particularly prominent role in astronomical observations. Their orientations belong to widespread alignment groups, mostly materialized in buildings of other types and explicable in terms of some fundamental concerns of the agriculturally-based Maya societies. I present the evidence demonstrating that the astronomical orientations initially embedded in E Groups, which represent the earliest standardized form of Maya monumental architecture and whose occurrence in practically all early cities in the central Yucatan peninsula attests to their socio-political significance, were later transferred to buildings and compounds of other types. Therefore, it is precisely the importance of the astronomically and cosmologically significant directions, first incorporated in E Groups, that allows us to understand some prominent aspects of ancient Maya architecture and urbanism.


Assuntos
Planejamento de Cidades/história , Civilização/história , Comportamento Ritualístico , Guatemala , História Antiga , Humanos , Atividade Solar
16.
Environ Sci Pollut Res Int ; 28(28): 38074-38084, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33725302

RESUMO

The number of sunspots shows the solar activity level. During the high solar activity, emissions of matter and electromagnetic fields from the Sun make it difficult for cosmic rays to penetrate the Earth. When solar energy is high, cosmic ray intensity is lower, so that the solar magnetic field and solar winds affect the Earth externally and originate new viruses. In this paper, we assess the possible effects of sunspot numbers on the world virus appearance. The literature has no sufficient results about these phenomena. Therefore, we try to relate solar ray extremum to virus generation and the history of pandemics. First, wavelet decomposition is used for smoothing the sunspot cycle to predict past pandemics and forecast the future time of possible virus generation. Finally, we investigate the geographical appearance of the virus in the world to show vulnerable places in the world. The result of the analysis of pandemics that occurred from 1750 to 2020 shows that world's great viral pandemics like COVID-19 coincide with the relative extrema of sunspot number. Based on our result, 27 pandemic (from 36) incidences are on sunspot extrema. Then, we forecast future pandemics in the world for about 110 years or 10 cycles using presented multi-step autoregression (MSAR). To confirm these phenomena and the generation of new viruses because of solar activity, researchers should carry out experimental studies.


Assuntos
COVID-19 , Atividade Solar , Humanos , Pandemias , SARS-CoV-2 , Luz Solar
17.
Environ Health ; 20(1): 28, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33722240

RESUMO

BACKGROUND: To examine the influence of solar cycle and geomagnetic effects on SLE disease activity. METHODS: The data used for the analysis consisted of 327 observations of 27-day Physician Global Assessment (PGA) averages from January 1996 to February 2020. The considered geomagnetic indices were the AP index (a daily average level for geomagnetic activity), sunspot number index R (measure of the area of solar surface covered by spots), the F10.7 index (measure of the noise level generated by the sun at a wavelength of 10.7 cm at the earth's orbit), the AU index (upper auroral electrojet index), and high energy (> 60 Mev) proton flux events. Geomagnetic data were obtained from the Goddard Space Flight Center Space Physics Data Facility. A time series decomposition of the PGA averages was performed as the first step. The linear relationships between the PGA and the geomagnetic indices were examined using parametric statistical methods such as Pearson correlation and linear regression, while the nonlinear relationships were examined using nonparametric statistical methods such as Spearman's rho and Kernel regression. RESULTS: After time series deconstruction of PGA averages, the seasonality explained a significant fraction of the variance of the time series (R2 = 38.7%) with one cycle completed every 16 years. The analysis of the short-term (27-day) relationships indicated that increases in geomagnetic activity Ap index (p < 0.1) and high energy proton fluxes (> 60 Mev) (p < 0.05) were associated with decreases in SLE disease activity, while increases in the sunspot number index R anticipated decreases in the SLE disease activity expressed as PGA (p < 0.05). The short-term correlations became statistically insignificant after adjusting for multiple comparisons using Bonferroni correction. The analysis of the long-term (297 day) relationships indicated stronger negative association between changes in the PGA and changes in the sunspot number index R (p < 0.01), AP index (p < 0.01), and the F10.7 index (p < 0.01). The long-term correlations remained statistically significant after adjusting for multiple comparisons using Bonferroni correction. CONCLUSION: The seasonality of the PGA averages (one cycle every 16 years) explains a significant fraction of the variance of the time series. Geomagnetic disturbances, including the level of geomagnetic activity, sunspot numbers, and high proton flux events may influence SLE disease activity. Studies of other geographic locales are needed to validate these findings.


Assuntos
Fenômenos Geológicos , Lúpus Eritematoso Sistêmico , Fenômenos Magnéticos , Humanos , Prótons , Índice de Gravidade de Doença , Atividade Solar
19.
Arh Hig Rada Toksikol ; 72(1): 23-28, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33787183

RESUMO

Ambient dose equivalent H*(10) is measured to assess general population exposure to ionising radiation. From its spatial and time variations it is possible to identify sources of exposure. In Slovenia, semi-annual H*(10) is measured routinely with thermoluminescence dosimeters at 66 locations around the Nuclear Power Plant (NPP) Krsko and at 50 other locations covering the rest of Slovenian territory. Since the Chernobyl accident contamination had ceased to contribute to ambient dose equivalents, we have been calculating correlation coefficients between annual mean number of sunspots and annual H*(10). These correlation coefficients were calculated for five locations in western Slovenia and for five annual H*(10) extracted from measurements around NPP Krsko. Their ranges between -0.64 and -0.38 suggest a clear negative correlation between solar activity and H*(10). Mean annual H*(10) averted by solar activity in the past two solar maxima reached 0.070 mSv around NPP Krsko (155 m.a.s.l.) and 0.132 mSv and 0.180 mSv at Kredarica (2515 m.a.s.l.). Quantifying the influence of the solar activity on the ambient dose equivalent helps us to better understand exposure of the general population to ionising radiation.


Assuntos
Dosímetros de Radiação , Atividade Solar , Humanos , Eslovênia
20.
Commun Biol ; 4(1): 124, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33504914

RESUMO

Bioregenerative life-support systems (BLSS) involving plants will be required to realize self-sustaining human settlements beyond Earth. To improve plant productivity in BLSS, the quality of the solar spectrum can be modified by lightweight, luminescent films. CuInS2/ZnS quantum dot (QD) films were used to down-convert ultraviolet/blue photons to red emissions centered at 600 and 660 nm, resulting in increased biomass accumulation in red romaine lettuce. All plant growth parameters, except for spectral quality, were uniform across three production environments. Lettuce grown under the 600 and 660 nm-emitting QD films respectively increased edible dry mass (13 and 9%), edible fresh mass (11% each), and total leaf area (8 and 13%) compared with under a control film containing no QDs. Spectral modifications by the luminescent QD films improved photosynthetic efficiency in lettuce and could enhance productivity in greenhouses on Earth, or in space where, further conversion is expected from greater availability of ultraviolet photons.


Assuntos
Produtos Agrícolas , Ambiente Controlado , Alface , Pontos Quânticos , Espectro de Ação/métodos , Espectro de Ação/normas , Biofortificação/métodos , Calibragem , Cobre/química , Produtos Agrícolas/química , Produtos Agrícolas/efeitos da radiação , Radiação Eletromagnética , Humanos , Alface/crescimento & desenvolvimento , Alface/metabolismo , Alface/efeitos da radiação , Luz , Fotossíntese/efeitos da radiação , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos da radiação , Melhoria de Qualidade , Pontos Quânticos/química , Atividade Solar , Sulfetos/química , Compostos de Zinco/química
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