Changes In Carbon Dioxide Concentration Research Articles

Accelerating the Diagnosis of Pandemic Infection Based on Rapid Sampling Algorithm for Fast-Response Breath Gas Analyzers

This paper presents a novel technique for extracting the alveolar part of human breath. Gas exchange occurs between blood and inhaled air in the alveoli, which is helpful in medical diagnostics based on breath analysis. Consequently, the alveolar portion of the exhaled air contains specific concentrations of endogenous EVOC (exogenous volatile organic compound), which, among other factors, depend on the person’s health condition. As this part of the breath enables the screening for diseases, accurate sample collection for testing is crucial. Inaccurate sampling can significantly alter the composition of the specimen, alter the concentration of EVOC (biomarkers) and adversely affect the diagnosis. Furthermore, the volume of alveolar air is minimal (usually <350 mL), especially in the case of people affected by respiratory system problems. For these reasons, precise sampling is a key factor in the effectiveness of medical diagnostic systems. A new technique ensuring high accuracy and repeatability is presented in the article. It is based on analyzing the changes in carbon dioxide concentration in human breath using a fast and compensated non-dispersive infrared (NDIR) sensor and the simple moving adjacent average (SMAA) algorithm. Research has shown that this method accurately identifies exhalation phases with an uncertainty as low as 20 ms. This provides around 350 ms of breath duration for carrying out additional stages of the diagnostic process using various types of analyzers.

Multi-Parameter Prediction of Solar Greenhouse Environment Based on Multi-Source Data Fusion and Deep Learning

In the process of agricultural production in solar greenhouses, the key to the healthy growth of greenhouse crops lies in accurately predicting environmental conditions. However, there are complex couplings and nonlinear relationships among greenhouse environmental parameters. This study independently developed a greenhouse environmental acquisition system to achieve a comprehensive method for the monitoring of the greenhouse environment. Additionally, it proposed a multi-parameter and multi-node environmental prediction model for solar greenhouses based on the Golden Jackal Optimization-Convolutional Neural Network-Bidirectional Gated Recurrent Unit-Self-Attention Mechanism (GCBS). The GCBS model successfully captures the complex nonlinear relationships in the greenhouse environment and accurately predicts changes in carbon dioxide concentration, air temperature and humidity, and soil temperature at different location nodes. To validate the performance of this model, we employed multiple evaluation metrics and conducted a comparative analysis with four baseline models. The results indicate that, while the GCBS model exhibits slightly higher computational time compared to the traditional Long Short-Term Memory (LSTM) network for time series prediction, it significantly outperforms the LSTM in terms of prediction accuracy for four key parameters, achieving improvements of 76.89%, 69.37%, 59.83%, and 56.72%, respectively, as measured by the Mean Absolute Error (MAE) metric.

The co-promoting mechanism of EMEA/DEEA/PZ ternary water-lean solvent on CO2 capture- a study based on 13C-qNMR and DFT calculations

Amine based CO2 absorption is currently the most promising means of capturing CO2 in industry, and the water-lean amine solvent has received widespread attentions. The reaction mechanism of the EMEA/DEEA/PZ ternary water-lean amine solvent (WLS) during the process of CO2 capture was investigated theoretically to understand the synergistic effect between the different amine components. The concentrations of intermediate products were analyzed by 13C-qNMR (quantitative Nuclear Magnetic Resonance) spectroscopy, while the reaction mechanisms were calculated using gaussian 16. The NMR results showed that carbamate (EMEACOO-), HCO3–/CO32– were the main products in the carbon capture process of EMEA WLS. The protonated amine concentration varies according to the change of carbon dioxide concentration. The balance between deprotonation (forming carbamates) and CO2 removal (regenerating EMEA) depends largely on how ampholytes interact with nearby water molecules. The DFT result showed that EMEA is the key component of CO2 capture, while DEEA and PZ primarily assist in transferring protons, catalyzing the conversion of H2CO3 into HCO3– to accelerate the process of CO2 capture. Furthermore, they assist in the redaction of EMEAH+ to EMEA, allowing it continue to participate in capture reactions. DEEA, PZ and water could promote activating the protonated EMEA and enhanced its capacity of CO2 capture. Furthermore, the desorption process confirmed the proton transfer from DEEAH+, ultimately leading to the regeneration of EMEA, thereby demonstrating the effective performance of regeneration.

Prediction of Atmospheric Carbon Dioxide Radiative Transfer Model based on Machine Learning

Global warming is caused by the increasing amount of greenhouse gases in the atmosphere. The Kyoto Protocol to the United Nations Framework Convention on Climate Change defines carbon dioxide (CO), methane (CH:), nitrous oxide (N0) fluorocarbons (HFC), holocarbon (PFC), and sulfur hexafluoride (SF.) Six gases are divided into the main greenhouse gases, of which CO, the largest proportion of emissions, is an important man-made greenhouse gas." As the main gas affecting the global greenhouse effect (75%), the amount of CO in the atmosphere has increased from 315 ppm in 1958 to 417 ppm in 2022, and global annual CO emissions have increased from 27 Pg to 49 Pg% over the past 40 years. Therefore, under the background of deep reinforcement learning, it is a problem that all countries pay more attention to predict the concentration emission of carbon dioxide to cope with the severe situation of climate warming. In order to obtain the radiative forcing value under the influence of carbon dioxide concentration, a simplified net radiative flux model is established. Based on the radiative transfer equation, this model can calculate the net radiative flux and radiative forcing of each layer of the atmosphere due to changes in carbon dioxide concentration. The results are compared with the RRTMG-LW long-wave radiative transfer model of American Center for Atmospheric and Environmental Research (AER) under the same factor, and the error is less than 1%.

교실 내 이산화탄소 농도와 소음 수준이 초등학생의 주의집중력과 문제행동에 미치는 영향

Objectives The purpose of this study is to examine changes in carbon dioxide concentration and noise levels in classrooms, and to analyze the effects of these changes on elementary school students' attention and problem behaviors. Methods First, To measure the change of carbon dioxide and noise levels in classrooms, theses levels were measured in general classroom, specific subject classroom, and specific subject classroom with ventilation system operating. Second, to analyze the effect of carbon dioxide and noise levels on students’ attention and problem behavior, situations where both carbon dioxide and noise levels are low (cLnL), only carbon dioxide levels are high (cHnL), and only noise levels are high (cLnH), and both carbon dioxide and noise levels are high (cHnH). Results The carbon dioxide concentration in each classroom ranged from 400 to 1951.8 ppm, and the noise level ranged from 12.6 to 96.6 db(A). As a result of analyzing the effects of carbon dioxide and noise levels on attention and problem behavior, it was resulted that the higher the noise level, the negatively correlated with Work instruction comprehension, Selective attention, and Sustained attention. In addition, problem behaviors occurred the least (3 times) in the cLnL group and the most (31 times) in the cHnH group. Conclusions Carbon dioxide concentration and noise levels in the school exceeded the standard. The learning environment can affect not only students' attention and problem behavior, but also their health. To improve this, physical environment improvement is required.

Cascading Impacts of Change in Carbon Dioxide Concentration, Temperature and Precipitation on Horticulture Crops: A Review

The impacts of an increase in carbon dioxide concentration, temperature and precipitation on physiology, yield and biochemical contents of horticulture crops including its mitigation measures are evident globally. This study mainly focuses on South-East Asia and Africa. We have reviewed crop-wise published literature mainly from 2000-2021 regarding the impacts of rising carbon dioxide concentration, temperature and precipitation on horticulture. Visible phenophase changes in horticultural crops such as budburst, leaf initiation, flowering, fruiting, seedling and the overall development stages of the crops are evident from the available literature. The prevalence of many diseases like blight, mildew, abaca, black sigatoka and Pierce’s disease are the results of climate change. Changes in the biochemical content of the horticulture crops such as tannins, flavonol, alcohol level, acidic content, starch, amino acids, lipids, chloroplasts, sugar, organic acids and antioxidants were observed. The recommended mitigation measures throughout the literature are delayed sowing dates, efficient seed varieties, controlled fertilizer use, soil moisture conservation and other biotechnological measures. Salinity, moisture and environmental stress-tolerant crops need to develop for better management of climate change. Breeding of short-duration and heat-tolerant varieties, vulnerability quantification and early warning disease forecasting are some of the important research areas.

Assessment and current dynamics of nutrients with reference to nitrogen attributes in subalpine forests of Western Himalaya, India.

Nitrogen is an essential macronutrient necessary for a variety of physiological processes in plants, available in numerous fractions, each of which has direct relationship with the area's environmental circumstances since it causes the formation of these fractions. Seasonal and altitudinal variations in nitrogen concentration were found to have a significant impact. The soil of the western Himalaya is rich in a variety of nutrients, notably nitrogen, which was a current source of worry. The study was conducted in north western Himalaya, and different fractions of nitrogen, viz., available nitrogen, total nitrogen, ammonical nitrogen, and nitrate nitrogen, were estimated with reference to different parameters. Annual retention potential was evaluated among various fractions, which yielded positive results, with Site 1 demonstrating the highest retention potential across all seasons. At various depths and seasons of the year, ammonical and nitrate nitrogen levels fluctuated. The findings revealed that the soil is rich in nitrogen fractions with variation directly related to changes in carbon dioxide concentration. Site 1 had the highest values of all the fractions and Site 4 the lowest, whereas the C/N ratio varied between sites. The study determined that nitrogen fractions were present in sufficient quantities and play an important role in the maintenance and growth of natural forests as well as in the reduction of carbon dioxide levels in the atmosphere.

Eficiência no uso de água e qualidade de cebola em cenários climáticos futuros

ABSTRACT Considering that changes in climatic parameters directly interfere in crop yields, this study aimed to evaluate the impact of changes in carbon dioxide concentrations, temperature and soil water availability on production, water-use efficiency and onion (Allium cepa L. cv. IPA 11) quality. Four levels of soil water availability (40, 60, 80 and 100 %) and two concentrations of atmospheric CO2 (770 and 390 ppm) were evaluated in three experiments with different temperature regimes (18-24-30, 22-28-34 and 26-32-38 ºC), in Phytotron growth chambers. The water-use efficiency, bulb diameter and weight, shoot dry weight, pulp frmness, soluble solids content, pH and titratable acidity were also evaluated. The increase in temperature reduces the production, and a higher soil water availability increases the production of IPA 11 onion bulbs. The temperature regime of 18-24-30 ºC and the water availability of 76.72 % provide the best water-use efficiency for the onion crop.

Investigating the Plastic Decomposing Ability of Tenebriomolitor Using Carbon Dioxide Sensors

According to a group of Stanford scientists, mealworms, the larva of darkling beetles, can digest Styrofoam, a type of polystyrene, and break it down into carbon dioxide. This paper investigates the plastic-digesting property of mealworms on different types of plastic, namely polystyrene (PS), low- density polyethylene (LDPE) and polyvinyl chloride (PVC). Since mealworms breathe in oxygen and exhale carbon dioxide. To measure the extent of plastic intake, we explored an alternative method to measure the extent of plastic digestion - using Arduino carbon dioxide sensors instead of calculating the difference in weight of plastic. As the increase in the exhalation of carbon dioxide is indicative of the amount of plastic consumed, the authors measured the change in carbon dioxide concentration of the mealworms' environment as they consume plastic. This is put into comparison with when the mealworms respire without food. The results show that mealworms consume Styrofoam to a certain extent. However, they are mostly unable to digest polyethylene and polyvinyl chloride, likely due to their elasticity and high density respectively.

ИССЛЕДОВАНИЕ ИЗМЕНЕНИЙ ГЛОБАЛЬНОГО КЛИМАТА КАК СЛОЖНОЙ СИСТЕМЫ С ИСПОЛЬЗОВАНИЕМ ВЕЙВЛЕТНЫХ ФАЗО-ЧАСТОТНЫХ ФУНКЦИЙ, ФАЗО-ЧАСТОТНЫХ И ФАЗО-ВРЕМЕННЫХ ХАРАКТЕРИСТИК ГЕЛИОКОСМИЧЕСКИХ И КЛИМАТИЧЕСКИХ ПЕРЕМЕННЫХ ЧАСТЬ 1

Актуальность исследования обусловлена необходимостью установления истинных причин и закономерностей изменений глобального климата на Земле как сложной системы. Цель: разработать и предложить эффективный метод извлечения информации об изменчивости переменных, содержащейся в исходных данных изменений гелиокосмических и климатических переменных, заданных в виде временных рядов, и применить этот метод для обоснования климатических изменений на Земле. Объекты: временные ряды изменений гелиокосмических и климатических переменных. Методы: непрерывное прямое вейвлет-преобразование исходных данных с использованием комплексного вейвлета 'cgau5' с вычислением их временных вейвлетных фазо-частотных функций, фазо-частотных и фазо-временных характеристик; оценка спектра периодичностей функций по фазо-временным характеристикам переменных; оценка и анализ плотностей распределений фазо-частотных и фазо-временных характеристик; оценка и анализ коэффициентов корреляций между фазо-частотными и фазо-временными характеристиками переменных в равных интервалах времени. Результаты. Получены временные вейвлетные фазо-частотные функции и их изображения, позволяющие визуализировать и оценить спектры периодичностей исследуемых переменных; оценки вейвлетные фазо-частотные и фазо-временные характеристики переменных, позволяющие проводить весь комплекс сравнительных исследований переменных и установить закономерности их изменений. К этим исследованиям относятся: оценивание плотностей распределений этих характеристик, позволяющих идентифицировать факторы, влияющие на эти изменения; вычисление матриц корреляций между вейвлетными фазо-частотными и фазо-временными характеристиками переменных в заданных равных интервалах времени, позволяющие оценить степени согласованности изменений переменных в фазо-частотной области и в области фазо-временных изменений. Установлена тесная взаимосвязь между колебательными процессами гелиокосмических переменных, солнечной активностью и вулканическими процессами на Земле, изменениями концентрации двуокиси углерода CO2 в атмосфере. Показано, что движение Солнца относительно барицентра, обусловленное движением планет-гигантов Cолнечной системы, управляет cолнечной активностью, тектоническими процессами на Земле, в том числе вулканическими извержениями, климатом на Земле.

Study of Air Quality in the Office Building

This paper is devoted to assessment of air quality in an office space of a public building. Analysis of the results of researches made in this area by Russian and foreign authors showed that state of human health deteriorates at CO2 concentration level of 600-800 ppm and more and this can lead to decrease in performance and increased fatigue of office workers. Long-term human exposure to carbon dioxide can lead to chronic diseases. Results of experimental study of changes in carbon dioxide concentration in 30 m2 office space of a public building when 5 people are continually present in the office are given in this paper. CO2 concentration measurement was carried out during 24 hour period using MT 8057 portable carbon dioxide detector. According to the measurements results, a graph of CO2 concentration changes versus time was drawn. Conclusion that, in some periods of working day, air quality was unsatisfactory (from 10:40 to 13:30 and from 14:45 to 19:00: CO2 concentration exceeded 1000 ppm) indicates insufficiency of existing ventilation system and excessive room sealing (due to application of plastic windows). There is a need in technical solutions to improve efficiency of supply and exhaust ventilation.

A Sensitivity Study of the 4.8 µm Carbon Dioxide Absorption Band in the MWIR Spectral Range

The measurements of gas concentrations in the atmosphere are recently developed thanks to the availability of gases absorbing spectral channels in space sensors and strictly depending on the instrument performances. In particular, measuring the sources of carbon dioxide is of high interest to know the distribution, both spatial and vertical, of this greenhouse gas and quantify the natural/anthropogenic sources. The present study aims to understand the sensitivity of the CO2 absorption band at 4.8 µm to possibly detect and measure the spatial distribution of emissions from point sources (i.e., degassing volcanic plumes, fires, and industrial emissions). With the aim to define the characteristics of future multispectral imaging space radiometers, the performance of the CO2 4.8 µm absorption band was investigated. Simulations of the “Top of Atmosphere” (TOA) radiance have been performed by using real input data to reproduce realistic scenarios on a volcanic high elevation point source (>2 km): actual atmospheric background of CO2 (~400 ppm) and vertical atmospheric profiles of pressure, temperature, and humidity obtained from probe balloons. The sensitivity of the channel to the CO2 concentration has been analyzed also varying surface temperatures as environmental conditions from standard to high temperature. Furthermore, response functions of operational imaging sensors in the middle wave infrared spectral region were used. The channel width values of 0.15 µm and 0.30 µm were tested in order to find changes in the gas concentration. Simulations provide results about the sensitivity necessary to appreciate carbon dioxide concentration changes considering a target variation of 10 ppm in gas column concentration. Moreover, the results show the strong dependence of at-sensor radiance on the surface temperature: radiances sharply increase, from 1 Wm−2sr−1µm−1 (in the “standard condition”) to >1200 Wm−2sr−1µm−1 (in the warmest case) when temperatures increase from 300 to 1000 K. The highest sensitivity has been obtained considering the channel width equal to 0.15 µm with noise equivalent delta temperature (NEDT) values in the range from 0.045 to 0.56 K at surface temperatures ranging from 300 to 1000 K.

Spatial and temporal variations of carbon dioxide and its influencing factors

The increase in carbon dioxide in the atmosphere is one of the main causes of global warming. Remote sensing technology has become an important means of monitoring the distribution of carbon dioxide gas. By remotely monitoring the temporal and spatial distributions of atmospheric carbon dioxide, people can further deepen their understanding of the global carbon process. The GOSAT (Greenhouse Gases Observing SATellite) CO2 L4B concentration data from 2010 to 2015 were validated using local station atmospheric data. The spatial and temporal distributions of the carbon dioxide concentration and its variation characteristics were analyzed. Based on the total primary productivity data and human emissions of carbon dioxide data, the influencing factors of spatial variations in carbon dioxide were analyzed. The results show that: (1) The correlation coefficient between GOSATL4B data and ground-measured data is above 0.95, which indicates that the remotely acquired data have high precision and stability. (2) The spatial distribution characteristics of carbon dioxide at different atmospheric pressure heights are quite different. The variation in the long-term series mean of carbon dioxide concentration levels at 17 vertical heights was studied. The fluctuations in concentration changes at different height levels vary, and the closer to the surface, the greater the fluctuation is. The near-surface carbon dioxide concentration (975 hPa) has the largest fluctuation. When the atmospheric pressure is low (for example, 150 or 100 hPa), the high carbon dioxide concentration region is banded and concentrated near the equator. The trends in carbon dioxide concentration over land and sea surfaces are similar, and the common pattern is that the concentration of carbon dioxide has been increasing. (3) The near-surface carbon dioxide concentration (975 hPa) has clearly different spatial characteristics. There are four high-value centers across the globe: East Asia, western Europe, the US East Coast, and Central Africa. The concentration of carbon dioxide in the Northern Hemisphere near the ground is higher than that in the Southern Hemisphere. The fluctuation in the Southern Hemisphere is relatively small, and the trend is opposite that in the Northern Hemisphere. (4) The concentration of carbon dioxide showed a significant growth trend during the study period. By studying the change characteristics of the monthly global average at the 975 hPa level (approximately 300 m above sea level) from January 2010 to October 2015, it can be seen that the global CO2 concentration has been above 400 ppm for most of the year, and it is increasing each year. (5) Compared with the Southern Hemisphere, the cyclical changes in carbon dioxide concentration in the Northern Hemisphere are obvious and large, while the trend in the Southern Hemisphere is relatively stable, and the change is small. There are opposite trends in the cyclical changes in the carbon dioxide concentration in the Northern and Southern Hemispheres. When the carbon concentration in the Northern Hemisphere resides over the annual high-value area, the Southern Hemisphere has a low-value area of carbon dioxide concentration every year. In addition, the change in carbon dioxide concentration during the year is obvious with seasonal changes. This should be related to changes in vegetation phenology and different seasons in the Northern and Southern Hemispheres. (6) Four countries in East Asia (Korea, Mongolia, Japan and China) from 2010 to 2014 were selected to analyze the relationship between GPP (gross primary production) and near-surface carbon dioxide concentration. These two factors have a significant inverse correlation. When carbon dioxide is at a minimum, the GPP is at its peak, and when carbon dioxide reaches its peak, the GPP reaches a minimum. The above relationship fully indicates that terrestrial ecosystems play an important role as carbon sink contributors in the carbon cycle. (7) The relationship between atmospheric carbon dioxide and carbon dioxide data from human activities from the Global Atmospheric Research Emissions Database was analyzed. The former is significantly and positively correlated with carbon dioxide emissions caused by human activities, indicating that human activities are an important factor in the increase in carbon dioxide.

New sensor measures biological activity in soil at field scale in real time

New sensor measures biological activity in soil at field scale in real time

Effects of Transport Duration and Water Quality on Age‐0 Walleye Stress and Survival

AbstractAge‐0 Walleye Sander vitreus are stocked to achieve several management objectives. However, stocked Walleye are exposed to numerous handling‐ and transport‐related stressors that can negatively influence disease resistance, survival, year‐class strength, and fisheries management objectives. The objective of this study was to evaluate relationships between Walleye transport duration with changes in water chemistry, whole‐blood glucose and plasma cortisol concentrations, and short‐term (48‐h) mortality. Walleye were transported between 3.5 and 6.0 h and stocked into holding cages located at one of seven sites. Water quality and stress (via whole‐blood glucose and plasma cortisol) and mortality were evaluated prior to, during, and at 0, 2, 24, and 48 h posttransportation. During transport, water temperatures generally decreased, while carbon dioxide concentrations fluctuated between 2.7 and 22.5 mg/L. Walleye whole‐blood glucose and plasma cortisol concentrations varied by site and time since transport. Changes in carbon dioxide concentrations were associated with changes in whole‐blood glucose concentrations. However, cumulative survival rates and plasma cortisol concentrations were not associated with water quality or transportation duration. Understanding Walleye tolerance to transportation‐induced stress has the potential to enhance stocking programs by providing the opportunity for managers to make informed transport decisions.

The measurement of soil gases and shallow temperature for determination of active faults in a geothermal area: a case study from Ömer–Gecek, Afyonkarahisar (West Anatolia)

Afyonkarahisar is a very important geothermal province of western Anatolia and has low and medium enthalpy geothermal areas. This study has been carried out for the preparation of distribution maps of soil gases (radon and carbon dioxide) and shallow soil temperature and the exploration of permeable tectonic regions associated with geothermal systems and reveal the origins of radon and carbon dioxide gases. The western district of the study area is characterized by the high radon concentration (168.30 kBq/m3), carbon dioxide ratio (0.30%), and soil temperature (21.0 °C) values. Fethibey and Demircevre faults, which allow the circulation of geothermal fluids, have been detected in the distribution maps of radon, carbon dioxide, and shallow depth temperature and the directions of the curves in these maps correspond to the strikes of Demircevre faults. The effect of the fault plays an important role in the change of carbon dioxide concentration along the W-E directional geological section prepared to determine the change of soil gas and shallow depth temperature values depending on lithological differences, fault existence, and geothermal reservoir depth. On the other hand, it was determined that Rn222 concentration and soil temperature changed as a function of geothermal reservoir depth or lithological difference. Tuffs in Koprulu volcano-sedimentary units are the main source of radon due to their higher uranium contents. Besides, the carbon dioxide in Omer–Gecek soils has geothermal origin because of the highest carbon dioxide content (99.3%) in non-condense gas. The similarities in patterns of soil temperature, radon, and carbon dioxide indicate that the variation in soil temperatures is related to radon and carbon dioxide emissions. It is concluded that soil gas and temperature measurements can be used to determine the active faults in the initial stage of geothermal exploration successfully.

A Gas Chromatographic Method for the Determination of Bicarbonate and Dissolved Gases

A gas chromatographic method for the rapid determination of aqueous carbon dioxide and its speciation into solvated carbon dioxide and bicarbonate is presented. One-half mL samples are injected through a rubber septum into 20-mL vials that are filled with 9.5 mL of 0.1 N HCl. A one mL portion of the headspace is withdrawn and injected onto a gas chromatograph equipped with a thermal conductivity detector. Using the dimensionless Henry’s constant for carbon dioxide and an adaptation of the Henderson-Hasselbalch equation, carbon dioxide in the samples can be categorized among solvated, bicarbonate, and carbonate forms. Natural water samples as well as wastewater from a municipal sewage treatment plant and a swine rearing operation were analyzed by this method and the results compared favorably to those obtained by titration. Samples stored for up to five weeks showed no significant changes in carbon dioxide concentrations. In addition, using flame ionization and electron capture detectors, methane and nitrous oxide concentrations in the samples were also measured.

Is cerebral vasomotor reactivity impaired in Parkinson disease?

The ability of a blood vessel to change diameter in response to a change in carbon dioxide concentration is often referred to as vasomotor reactivity. This study aimed to determine whether vasomotor reactivity is impaired in patients with idiopathic Parkinson's Disease in comparison to healthy controls. Transcranial Doppler was used to measure cerebral blood flow velocity in the middle cerebral arteries at baseline and under hypocapnic conditions in 40 patients with idiopathic Parkinson's disease and 50 healthy controls. Vasomotor reactivity, assessed under hypocapnic conditions, is not impaired in patients with idiopathic Parkinson's Disease in comparison to healthy controls.

Volcanic Eruptions in South Europe and the Change of Carbon Dioxide Concentration – Case Study: "Moussala" Basic Environmental Observatory

Volcanic Eruptions in South Europe and the Change of Carbon Dioxide Concentration – Case Study: "Moussala" Basic Environmental Observatory

A study of different‑scale relationship between changes of the surface air temperature and the СО2 concentration in the atmosphere

A concept of the anthropogenic origin of the current global climate warming assumes that growth of concentration of the atmospheric carbon dioxide and other greenhouse gases is of great concern in this process. However, all earlier performed analyses of the Antarctic ice cores, covering the time interval of several glacial cycles for about 1 000 000 years, have demonstrated that the carbon dioxide concentration changes had a certain lag relative to the air temperature changes by several hundred years during every beginning of the glacial terminations as well as at endings of interglacials. In contrast to these findings, a recently published careful analysis of Antarctic ice cores (Parrenin et al., 2013) had shown that both, the carbon dioxide concentration and global temperature, varied almost synchronously during the transition from the last glacial maximum to the Holocene. To resolve this dilemma, a special technique for analysis of the paleoclimatic time series, based on the wavelets, had been developed and applied to the same carbon dioxide concentration and temperature time series which were used in the above paper of Parrenin et al., 2013. Specifically, a stack of the Antarctic δ18O time series (designated as ATS) and the deuterium Dome C – EPICA ones (dD) were compared to one another in order to: firstly, to quantitatively estimate differences between time scales of these series; and, secondly, to clear up the lead–lag relationships between different scales variations within these time series. It was found that accuracy of the mutual ATS and dD time series dating lay within the range of 80–160 years. Perhaps, the mutual dating of the temperature and carbon dioxide concentration series was even worse due to the assumed displacement of air bubbles within the ice. It made us to limit our analysis by the time scales of approximately from 800 to 6000 years. But it should be taken into account that any air bubble movement changes the time scale of the carbon dioxide series as a whole. Therefore, if a difference between variations in any temperature and the carbon dioxide time series is found to be longer than 80–160 years, and if these variations are timescale‑dependent, it means that the bubble displacements are not essential, and so these advancing and delays are characteristic of the time series being compared. Our wavelet‑based comparative and different‑scale analysis confirms that the relationships between the carbon dioxide concentration and temperature variations were essentially timescale‑dependent during the transition from the last glacial maximum to the Holocene. The carbon dioxide concentration variations were ahead of the temperature ones during transition from the glacial maximum to the Boelling – Alleroud warming as well as from the Young Drias cooling to the Holocene optimum. However, the temperature variations were ahead during the transition from the Boelling – Alleroud warming to the Young Drias cooling and during the transition from the Holocene optimum to the present‑day climate.