Analysis Of Diurnal Variation Research Articles

Cng-term variations and trends of tropospheric and ground-level NO2 over typical coastal areas

Tropospheric and ground-level levels of nitrogen dioxide (NO2) may have changed due to environmental policies and technological changes. Here, multiyear ground-based measurement (2014–2022) and satellite-derived retrieval (October 2004 to May 2023) datasets of NO2 concentrations are used to study the long-term ground-level and tropospheric NO2 patterns and trends at four time scales (interannual, quarterly, monthly, and hourly) over the three regions with the highest global NO2 concentrations. Several tropospheric NO2 hotspots are observed over industrialized and highly populated coastal zone areas. Over the past 18 years, these hotpots have generally decreased due to the implementation of strong and effective environmental protection policies. A significant trend reversal was observed in 2011 in East-central China. The maximum values of tropospheric NO2 occurred in winter over East-central China, Western Europe and East-central USA, with concentrations of 13.010, 4.243 and 4.149 × 1015 molecules cm−2, respectively. The Bohai Sea exhibited disproportionately high tropospheric NO2 levels, suggesting it as a significant contributor to regional nitrogen pollution. Ground-level NO2 shows similar temporal patterns to tropospheric concentrations, with over 82.8 % of sites in East-central China exceeding 30 μg m−3, compared to 12.8 % in Western Europe and 3.8 % in East-central USA. The analysis of diurnal variations in ground-level NO2 concentrations shows a significantly decrease during the daytime compared to nighttime, reflecting that the peak occurs at approximately 08:00 and 20:00 LT, while the lowest concentrations at around 12:00 LT. These insights clarify the impacts of environmental policies on NO2 levels and identify critical areas for targeted pollution control, enhancing our understanding of NO2 dynamics in high-pollution regions globally.

Analysis of diurnal variation in serum testosterone levels in men with symptoms of testosterone deficiency.

Testosterone (T) plays a crucial role in various physiological functions in men, and understanding the variations in T levels during the day is essential for diagnosing and treating testosterone deficiency (TD). We sought to evaluate the reduction in serum total T (TT) levels throughout the day in men with symptoms of testosterone deficiency and to determine the variables having an impact on the extent of this decline. The study population consisted of a group of men who within 3months of each other had all undergone both early morning and afternoon TT level measurements. We did not include patients with a history of a prior orchiectomy, testosterone levels below 100ng/dL or above 1000ng/dL, a history of androgen deprivation therapy, or patients on T therapy. Statistical analyses were conducted using descriptive statistics, t-tests, chi-square tests, and correlation calculations. Liquid chromatography-tandem mass spectrometry was used to measure TT, and a change in TT levels greater than 100ng/dL was considered significant. Using multivariable and univariable analysis, we attempted to define predictors of a decrease in afternoon TT levels. The majority of men showed no significant difference in T levels between morning and afternoon. In total, 506 men with a median age of 65years were analyzed. The most common comorbidities were hypertension and hyperlipidemia. Levels of TT were measured in the morning and afternoon, and no significant differences in mean T levels based on the time of the test were found. Age was not significantly associated with T levels. There was a weak negative correlation between age and the difference between morning and afternoon T levels, with younger men showing more significant variations in T levels. The most considerable differences in T levels were observed in men younger than 30 years. There were no predictors of the magnitude of the T decrease in the afternoon. Strengths of the study include the number of subjects and the use of liquid chromatography-tandem mass spectrometry for T measurement. Limitations include failure to measure morning and afternoon T levels on the same day, the retrospective nature of the study, and a smaller sample size of patients younger than 30years. In this study we found no strong link between age and daily T fluctuation, but we observed a decrease in the magnitude of variation with aging. The group experiencing the most significant decline in daily T had higher morning and consistently normal afternoon T levels.

Analysis of diurnal variations in body weight of wean-to-finish pigs

Analysis of diurnal variations in body weight of wean-to-finish pigs

Analysis of Diurnal Variations in Heart Rate: Potential Applications for Chronobiology and Cardiovascular Medicine.

Circadian factors likely influence the occurrence, development, therapy, and prognosis of cardiovascular diseases (CVDs). To determine the association between the heart rate (HR) diurnal parameters and CVD risks, we designed an analytical strategy to detect diurnal rhythms of HR using longitudinal data collected by clinically used Holter monitors and wearable devices. By combining in-house developed algorithms with existing analytical tools, we obtained trough phase and nocturnal variation in HR for different purposes. The analytical strategy is robust and also sensitive enough to identify variations in HR rhythms influenced by multiple effectors such as jet lag, geological location and altitude, and age from total 211 volunteers. A total of 10,094 sets of 24-h Holter ECG data were analyzed by stepwise partial correlation to determine the critical points of HR trough phase and nocturnal variation. The following HR diurnal patterns correlate with high CVD risk: arrhythmic pattern, anti-phase pattern, rhythmic patterns with trough phase less than 0 (extremely advanced diurnal pattern) or more than 5 (extremely delayed diurnal pattern), and nocturnal variation less than 2.75 (extremely low) or more than 26 (extremely high). In addition, HR trough phases from wearable devices were nearly identical to those from 24-h Holter monitoring from 12 volunteers by linear correlation and Bland-Altman analysis. Our analytical system provides useful information to identify functional diurnal patterns and parameters by monitoring personalized, HR-based diurnal changes. These findings have important implications for understanding how a regular heart diurnal pattern benefits cardiac function and raising the possibility of non-pharmacological intervention against circadian related CVDs. With the rapid expansion of wearable devices, public cardiovascular health can be promoted if the analytical strategy is widely applied.

Utilization of GOCI data to evaluate the diurnal vertical migration of Microcystis aeruginosa and the underlying driving factors

Cyanobacterial blooms are one of the most severe ecological problems affecting lakes. The vertical migration of cyanobacteria in the water column increases the uncertainty in the formation and disappearance of blooms, which may be closely associated with light, temperature, and wind speed. However, it is difficult to quantitatively evaluate the influencing factors of cyanobacteria vertical movement in natural environment compared to the laboratory experimental environment. Besides, both field survey and laboratory experiment method have the difficulties in determining the diurnal vertical migration of cyanobacteria at the synoptic lake scale. In this study, based on the diurnal dynamics of cyanobacterial bloom intensity (CBI) observed by the Geostationary Ocean Color Imager (GOCI) from 2011 to 2019, the daily variations, floating rate, and sinking rate of Microcystis aeruginosa were calculated in the natural environment. Then, the effects of light, temperature, and wind speed on the vertical migration of M. aeruginosa were analysed from the perspectives of day, night, and season. The results are as follows: the records of three typical patterns of diurnal CBI exhibited strong seasonal variability from the 9-year statistics; at night, the buoyancy recovery rate of cyanobacterial colonies increased with temperature, so that at temperature >15 °C and wind speed <3 m s−1, CBI reached the maximum of the whole day at 08:16; the sinking rate of M. aeruginosa was positively correlated with the cumulated light energy at both synoptic and pixel scale; the upward migration speed of M. aeruginosa was positively correlated with the maximum wind speed of the day before cyanobacterial bloom. Therefore, the severer cyanobacterial blooms were often observed by satellite images after strong winds. The analysis of diurnal variation, floating rate, and sinking rate of M. aeruginosa will expand our knowledge for further understanding the formation mechanism of cyanobacterial blooms and for improving the accuracy of model simulation to predict the hourly changes in cyanobacterial blooms in Lake Taihu.

Spatial and Temporal Variations of Airborne Poaceae Pollen along an Urbanization Gradient Assessed by Different Types of Pollen Traps

Grass pollen allergy is widespread all around the globe. With an increasing number of people living in cities, the examination of grass pollen levels within cities and their surroundings has increased in importance. The aim of this study was to examine different temporal and spatial scales of grass pollen concentration and deposition across urban and semi-rural environments in the years 2019 and 2020. We installed different types of pollen traps in the city of Ingolstadt (Bavaria, Germany) and its surroundings: volumetric pollen traps at roof level to assess background pollen concentration and gravimetric pollen traps and portable volumetric traps at street level. We considered grass pollen concentration and deposition in the context of land use and management. Our data showed that the grass pollen season in 2020 was longer and more intense than in 2019. Background grass pollen concentration was generally higher at the semi-rural site in both years: peak values were eight times (2019) and more than four times (2020) higher, and Seasonal Pollen Index was more than four times and almost three times higher in 2019 and 2020, respectively. Analyses of spatial variations measured at street level revealed higher numbers for pollen deposition and concentrations at semi-rural than at urban sites. Recorded values were linked to local vegetation and the management of grass areas surrounding the traps. Analyses of diurnal variations at street level in June 2019 showed that pollen concentration for all sites, independent of their degree of urbanization, were highest at noon (22.2 pollen grains/m³ vs. 8.5 pollen grains/m³ in the morning and 10.4 pollen grains/m³ in the evening). Diurnal variations at roof level showed similarities for the same days but differed when considering the whole season. Our data suggest the importance of the management of grass areas as areas cut earlier have a decreased amount of emitted pollen.

Experimental Analysis of Diurnal Variations in Humic-Like Fluorescent Dissolved Organic Matter in Surface Seawater

Humic-like fluorescent dissolved organic matter (FDOM) have been widely used as tracers for bio-refractory dissolved organic matter to understand its dynamics in the oceans. Vertical distributions of humic-like FDOM are controlled by microbial production in the ocean interiors and photobleaching in surface layers. Although humic-like FDOM is expected to be actively produced in surface layers with high bacterial activity, its production in surface seawater is not well understood. To examine the diurnal variations in humic-like FDOM due to microbial production and photobleaching in surface seawater, we conducted seven experiments from night to day using surface seawater in the subtropical Pacific and coastal regions. Parallel factor analysis determined that FDOM in the incubated seawater was composed of three components: two types of humic-like FDOM and a protein-like FDOM. The fluorescence intensity of humic-like FDOM increased to 104.0 ± 2.5% of the initial intensity during the night and decreased to 101.2 ± 2.5% under sunlight exposure during the day. Conversely, its intensity significantly increased to 114.0 ± 2.7% under dark conditions during the day. The turnover rates of humic-like FDOM by the increase and decrease in its intensity were estimated to be 0.14 and 0.11 d–1, respectively. These comparable turnover rates indicated that the production and photobleaching of humic-like FDOM were almost in equilibrium in the surface layer, with a low level of humic-like FDOM. Linear correlations between the intensity of humic-like FDOM and concentrations of dissolved oxygen in all experiments under dark conditions indicated that humic-like FDOM were produced as the by-products of microbial respiration processes in the surface seawater. Using global bacterial respiration rates, the net production rate of humic-like FDOM in the global photic layer was estimated as 4.2–5.5 x 1017 R.U. yr–1, contributing to 75% of its production in the entire ocean.

Worsening of Heat Stress Due To Global Warming in South Korea Based on Multi‐RCM Ensemble Projections

AbstractThis study assesses the future changes in summer (June–July–August; JJA) heat stress over South Korea under global warming. To better resolve the region‐specific changes in terms of geographical patterns and severity of heat stress in the Korean peninsula, four regional climate models (RCMs) are used for dynamical downscaling of Hadley Centre Global Environmental Model version 2—Atmosphere and Ocean global projections forced by two Representative Concentration Pathway (RCP4.5 and RCP8.5) scenarios. Dynamically downscaled simulations (horizontal resolution of 12.5 km and output interval of 3 h) facilitate in‐depth analysis of diurnal variation and extremes over South Korea, as well as focusing on the particular location, Daegu, that is characterized by high vulnerability to rising temperature. Both maximum temperature and heat stress indices such as wet bulb globe temperature and apparent temperature, which include the effect of humidity, are examined in order to comprehensively interpret the behaviors of heat stress in response to anthropogenic climate change. Ensemble projections reveal robust patterns of temperature and resultant humidity increases that are roughly constrained by the approximate 7%/K increase in the moisture holding capacity. The changes in temperature and humidity are directly transmitted to the heat stress indices, showing a significant increase. The heat stress is exacerbated in a differentiated way, with more intensification in diurnal variation at nighttime and in regional variation at low‐elevation basins. Both RCP4.5 and RCP8.5 scenarios project the statistical likelihood of a notable increase of extreme heat stress indices, much stronger and more extended heat waves, and the emergence of a long period of consecutive tropical nights.

Comparative analysis of diurnal variations of the lipid composition in perch (Perca fluviatilis L.) and tyulka (Clupeonella cultriventris Nordmann) from the Rybinsk Reservoir pelagial

Diurnal variations of the total content and fractional composition of lipids in the organisms of underyearlings of indigenous (perch) and nonindigenous (tyulka) species have been analyzed. These fish species form the basis of feeding aggregations of young fish in the Rybinsk Reservoir pelagial. Stable interspecific differences in mean daily and hourly values of the content of total lipids and in the level of three fractions-phospholipids (PLs), cholesterol (CS), and triacylglycerols (TAGs)—have been determined. It is shown that the level of adipose reserves and the content of TAG in the tyulka are higher than in perch, while the contents of PL and CS are lower. Diurnal variations of the level of each of the three fractions in both fish species are similar, but the ranges of variations are wider in tyulka than in perch. Possible mechanisms for the regulation of lipid metabolism (including the participation of neuroendocrinal centers) and their similarity in young fish of different species upon adaptation to short-term changes in the environment have been discussed. It is suggested that the modern state of the zooplankton community in the Rybinsk Reservoir pelagial negatively affects the feeding of perch underyearlings and parameters of lipid metabolism in their organisms.

CO2 Emission from oligotrophic peatland soil of Western Siberia

В работе представлены результаты исследования суточной и сезонной динамики эмиссии СО2 с поверхности олиготрофного болота в южно-таежной подзоне Западной Сибири в 2005-2007 гг. В течение летнего периода происходит увеличение интенсивности эмиссии СО2 от весны к середине лета и последующее снижение к осени. Среднее значение эмиссии СО2 составило 118 мгСО2 ⋅м-2⋅ч-1. Анализ суточной динамики эмиссии СО2 показал, что максимальный поток СО2 наблюдается в 16 часов, а минимальный - в 7 часов утра. Средняя амплитуда суточных колебаний эмиссии СО2 составляет 74 мгСО2 ⋅м-2⋅ч-1. Выявленные зависимости между температурой воздуха и потоком СО2 позволили рассчитать эмиссию углекислого газа в периоды между измерениями. Было выявлено, что для оценки эмиссии СО2 камерным методом в летнее время, оптимальным является период с 10 часов утра до 13 часов.

Soil CO2 concentrations and their implications in conventional and no-tillage agricultural fields

Soil CO2 concentrations to a depth of 50 cm depth were monitored with Vaisala CO2 probes from June 2004 to May 2005 in conventionally plowed and no-tillage agricultural plots and found to be generally higher in the former than the latter. Soil CO2 concentrations were also higher in summer and lower in winter, but were modulated by harvesting and the application of crop residues. Analysis of diurnal variations in soil CO2 concentrations, soil CO2 effluxes, and soil temperatures revealed distinct differences between plots. The relative amplitudes of the variation in CO2 concentrations peaked at a soil depth of 5 cm. Soil CO2 concentrations were higher when there was higher soil water content after precipitation, while soil CO2 effluxes were lower under the same circumstances. These two results relate to the lower diffusivity at higher soil water content, which restricts CO2 efflux, leading to higher soil CO2 concentrations. Calculations reveal that in the shallower soil layer (0-5 cm), CO2 production was greater in no-tillage plots, whereas in the deeper layer (15-25 cm), it was greater in conventional plots.

Dynamics of Air Pollution Transport in Late Wintertime over Kathmandu Valley, Nepal: As Revealed with Numerical Simulation

Abstract Air pollution characteristics over the Kathmandu Valley in wintertime were numerically investigated by using a comprehensive transport–chemistry–deposition model of air pollutants together with the fifth-generation Pennsylvania State University–NCAR Mesoscale Model (MM5). In Kathmandu, Nepal, it is known that double-layered local flows, that is, the southwesterly and northwesterly winds, formed as combined valley wind and plain-to-plateau wind, develop every day in the afternoon. In this study, the effect of local flows on air pollution in Kathmandu has been clarified. Detailed analysis of diurnal variation of air pollution transport elucidated the basic nature of the air pollution: 1) the vertical spreading of the pollutants, accumulated during the nighttime, by mixing-layer activity in the late morning, before the intrusion of the two local flows; 2) the late afternoon redevelopment of a shallow polluted layer and the pollutant transport toward the eastern neighboring valley, caused by the doub...

An Arabidopsis thaliana knock-out mutant of the chloroplast triose phosphate/phosphate translocator is severely compromised only when starch synthesis, but not starch mobilisation is abolished.

The Arabidopsis thaliana tpt-1 mutant which is defective in the chloroplast triose phosphate/phosphate translocator (TPT) was isolated by reverse genetics. It contains a T-DNA insertion 24 bp upstream of the start ATG of the TPT gene. The mutant lacks TPT transcripts and triose phosphate (TP)-specific transport activities are reduced to below 5% of the wild type. Analyses of diurnal variations in the contents of starch, soluble sugars and phosphorylated intermediates combined with 14CO2 labelling studies showed, that the lack of TP export for cytosolic sucrose biosynthesis was almost fully compensated by both continuous accelerated starch turnover and export of neutral sugars from the stroma throughout the day. The utilisation of glucose 6-phosphate (generated from exported glucose) rather than TP for sucrose biosynthesis in the light bypasses the key regulatory step catalysed by cytosolic fructose 1,6-bisphosphatase. Despite its regulatory role in the feed-forward control of sucrose biosynthesis, variations in the fructose 2,6-bisphosphate content upon illumination were similar in the mutant and the wild type. Crosses of tpt-1 with mutants unable to mobilise starch (sex1) or to synthesise starch (adg1-1) revealed that growth and photosynthesis of the double mutants was severely impaired only when starch biosynthesis, but not its mobilisation, was affected. For tpt-1/sex1 combining a lack in the TPT with a deficiency in starch mobilisation, an additional compensatory mechanism emerged, i.e. the formation and (most likely) fast turnover of high molecular weight polysaccharides. Steady-state RNA levels and transport activities of other phosphate translocators capable of transporting TP remained unaffected in the mutants.

The Jungfraujoch high‐alpine research station (3454 m) as a background clean continental site for the measurement of aerosol parameters

The first annual data set of climatically important aerosol parameters, measured at the Jungfraujoch (JFJ) high‐alpine research station (3454 m, Switzerland) from an ongoing field campaign since July 1995, is presented. Analysis of diurnal variations in continuous measurements of the total and backward hemispheric scattering coefficients (σSP, σBSP), the absorption coefficient (σAP, from aethalometer data), condensation nuclei (CN) concentration, and epiphaniometer signal (related to surface area (S) concentration) established the diurnal period 0300 – 0900 as being representative of the free tropospheric background aerosol. The annual data set was then edited to omit (1) the period 0900–0300 (i.e., 18 hours), taken to represent possible planetary boundary layer influenced conditions and (2) in‐cloud conditions using a cloud liquid‐water monitor. The seasonal aerosol cycle exhibited a July maximum and a December minimum in most aerosol parameters. Typical monthly median values for the free troposphere exhibit the following seasonal maxima and minima, respectively: σSP (550 nm) ∼ 16.1 and 0.43 × 10−6 m−1, σBSP (550 nm) ∼ 2.10 and 0.09 × 10−6 m−1, σAP (550 nm) ∼ 10.4 and 0.76 × 10−7 m−1 (≈ 104 and 7.6 ng m−3 black carbon), CN concentration ∼ 670 and 280 cm−3, and epiphaniometer signal ∼ 9.26 and 0.67 counts s−1 (S concentration ≈24.1 and 1.7 μm2 cm−3). Aerosol parameters were found to be comparable in magnitude to other NOAA baseline and regional stations and suggest that a clean continental designation for the JFJ site is applicable, when removing the planetary boundary layer influenced period.

Quantitative analysis of diurnal variation in volume and water content of lumbar intervertebral discs

Quantitative analysis of diurnal variation in volume and water content of lumbar intervertebral discs

担癌状態における血中コルチゾールレベル日内変動の解析

担癌状態における血中コルチゾールレベル日内変動の解析

Diurnal variations of upper winds in summer in Alberta

Abstract Analysis of diurnal variations of upper winds in summer in Alberta reveals features consistent with the hypothesis of a thermally‐induced wind system resulting from the juxtaposition of the Rocky Mountains and the Prairies. These include diurnal variation of flow that is most pronounced at two levels, one near the surface and one near the level of the mountain tops. Attempts to find a connection between such a system and occurrence of hail were unsuccessful.

Diurnal Variation of Radio Refractivity over India for Altitudes upto 3 km

Path loss trials indicate a high correlation between signal strength and radio refractivity at surface and aloft. Detailed studies have therefore been carried out in temperate latitudes to estimate diurnal variations of radio-refractivity and to assess their effects on tropospheric communications and radar ranges. Similar studies could not be attempted in the tropics due to lack of upper air data. Radio-sonde ascents are made in India only twice a day and twelve hourly data are not adequate for analysis of diurnal variation. However in 1960–1961, radio-sonde ascents were arranged at six hourly intervals at New Delhi, Calcutta, Bombay and Madras in four representative months July, October, January and April. Based on these data, six hourly refractive indices from surface to about 3 km have been compiled and diurnal variations of radio refractivity analysed. In view of their importance to system engineers, diurnal variations of the effective earth's radius factor (k) and radio horizon at these four places h...

Physicochemical treatment of an Australian municipal wastewater

Physicochemical treatment of wastewater from a typical Australian suburb is being investigated in a pilot plant facility near Melbourne, Victoria. Lime-coagulation at high pH, ammonia stripping and activated carbon treatment are being monitored. in various modes. Analyses of diurnal variations in incoming wastewater quality and typical resultant product waters are quoted. Experience has shown that the system can be operated in a simple practical manner to produce a high-quality water suitable for reuse by industry, or for discharge to a critical watercourse. The ease with which the system can be started up or adjusted for varying flow would be of benefit for holiday resorts or for temporary facilities in a rapidly expanding development.

The significance of the harmonic analysis of diurnal variation of pressure. A contribution to the discussion of Mr. E. G. Bilham's paper

The significance of the harmonic analysis of diurnal variation of pressure. A contribution to the discussion of Mr. E. G. Bilham's paper