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This study characterizes cancer and non-cancer risks due to inhalation exposure to volatile organic compounds (VOCs) in a border city of Windsor in southern Ontario, Canada, using hourly ambient concentrations collected from 17 November 2021 to 17 March 2023. The total incremental lifetime cancer risk (CR) due to benzene and ethylbenzene is 4.33 × 10−6, which is in the acceptable risk range of 1 × 10−6 to 1 × 10−4 used by the USEPA. The CR was higher in winter (5.20 × 10−6), followed by fall (4.32 × 10−6), spring (3.86 × 10−6), and summer (2.96 × 10−6), all in the acceptable range. The total chronic non-cancer risk (Hazard Quotient, HQ) of inhalation exposure to 16 VOCs was 0.0488, with a higher value in fall (0.0571), followed by winter (0.0464), and lower in spring (0.0454) and summer (0.0451), all in the safe level of below HQ = 1 used by the USEPA. The hazard index (HI) by organs was higher for the nervous system (0.0213), followed by the hematologic system and immune system (0.0165 each), but much lower for the other five target organs, i.e., the liver/kidney (1.52 × 10−4), developmental system (3.38 × 10−4), endocrine system and urinary system (2.82 × 10−4 each), and respiratory system (9.70 × 10−5). Similar hour-of-day trends were observed in the total CR, total HQ, and HI by organs with higher values in the early morning hours of 5:00–8:00 and lower values during 12:00 to 15:00. Benzene was the major contributor to both total CR (89%) and total HQ (34%) due to its high toxicity and high concentrations. Benzene, toluene, ethylbenzene, and xylenes (BTEX) contributed 100% of the total CR and 51% of the total HQ. Further, BTEX is the sole contributor to the HI for the hematologic system and immune system and the major contributor to the HI for the nervous system (39%) and developmental system (55%). Higher cancer and non-cancer risks were associated with the airmass from the east, southeast, and southwest of Windsor. [ABSTRACT FROM AUTHOR]

Abstract Background Studies suggest that cerebrospinal fluid (CSF) levels of amyloid-β (Aβ)42 and Aβ40 present a circadian rhythm. However sustained sampling of large volumes of CSF with indwelling intrathecal catheters used in most of these studies might have affected CSF dynamics and thereby confounded the observed fluctuations in the biomarker levels. Methods We included 38 individuals with either normal (N = 20) or abnormal (N = 18) CSF Aβ42/Aβ40 levels at baseline. CSF and plasma were collected at two visits separated by an average of 53 days with lumbar punctures and venipunctures performed either in the morning or evening. At the first visit, sample collection was performed in the morning for 17 participants and the order was reversed for the remaining 21 participants. CSF and plasma samples were analyzed for Alzheimer’ disease (AD) biomarkers, including Aβ42, Aβ40, GFAP, NfL p-tau181, p-tau217, p-tau231 and t-tau. CSF samples were also tested using mass spectrometry for 22 synaptic and endo-lysosomal proteins. Results CSF Aβ42 (mean difference [MD], 0.21 ng/mL; p = 0.038), CSF Aβ40 (MD, 1.85 ng/mL; p

Background: Studies suggest that cerebrospinal fluid (CSF) levels of amyloid-β (Aβ)42 and Aβ40 present a circadian rhythm. However sustained sampling of large volumes of CSF with indwelling intrathecal catheters used in most of these studies might have affected CSF dynamics and thereby confounded the observed fluctuations in the biomarker levels. Methods: We included 38 individuals with either normal (N = 20) or abnormal (N = 18) CSF Aβ42/Aβ40 levels at baseline. CSF and plasma were collected at two visits separated by an average of 53 days with lumbar punctures and venipunctures performed either in the morning or evening. At the first visit, sample collection was performed in the morning for 17 participants and the order was reversed for the remaining 21 participants. CSF and plasma samples were analyzed for Alzheimer' disease (AD) biomarkers, including Aβ42, Aβ40, GFAP, NfL p-tau181, p-tau217, p-tau231 and t-tau. CSF samples were also tested using mass spectrometry for 22 synaptic and endo-lysosomal proteins. Results: CSF Aβ42 (mean difference [MD], 0.21 ng/mL; p = 0.038), CSF Aβ40 (MD, 1.85 ng/mL; p < 0.001), plasma Aβ42 (MD, 1.65 pg/mL; p = 0.002) and plasma Aβ40 (MD, 0.01 ng/mL, p = 0.002) were increased by 4.2-17.0% in evening compared with morning samples. Further, CSF levels of 14 synaptic and endo-lysosomal proteins, including neurogranin and neuronal pentraxin-1, were increased by 4.5-13.3% in the evening samples (MDrange, 0.02-0.56 fmol/µl; p < 0.042). However, no significant differences were found between morning and evening levels for the Aβ42/Aβ40 ratio, different p-tau variants, GFAP and NfL. There were no significant interaction between sampling time and Aβ status for any of the biomarkers, except that CSF t-tau was increased (by 5.74%) in the evening samples compared to the morning samples in Aβ-positive (MD, 16.46 ng/ml; p = 0.009) but not Aβ-negative participants (MD, 1.89 ng/ml; p = 0.47). There were no significant interactions between sampling time and order in which samples were obtained. Discussion: Our findings provide evidence for diurnal fluctuations in Aβ peptide levels, both in CSF and plasma, while CSF and plasma p-tau, GFAP and NfL were unaffected. Importantly, Aβ42/Aβ40 ratio remained unaltered, suggesting that it is more suitable for implementation in clinical workup than individual Aβ peptides. Additionally, we show that CSF levels of many synaptic and endo-lysosomal proteins presented a diurnal rhythm, implying a build-up of neuronal activity markers during the day. These results will guide the development of unified sample collection procedures to avoid effects of diurnal variation for future implementation of AD biomarkers in clinical practice and drug trials. [ABSTRACT FROM AUTHOR]

The diurnal variability of mixed layer (ML) overturning instabilities remains poorly understood due to the challenge in capturing their rapid evolutions across large spatiotemporal ranges. Using high‐resolution data from 52 gliders in the South China Sea, we examine the diurnal modulations of ML overturning instabilities. The results of the 3‐month field observation show that negative potential vorticity occupies ∼16% of the ML and facilitates several types of forced overturning instabilities, especially symmetric instability (SI). Surface heat fluxes are identified to primarily modulate the diurnal variability of these overturning cells, where nighttime surface cooling is found to energize SI with an ∼2‐hr phase lag. As a result, over 60% of forced submesoscale overturning cells tend to restratify the ML at night. These findings quantitatively highlight the modulation of diabatic atmospheric forcing in submesoscale restratification, which should be considered in submesoscale parameterizations of ocean and climate models. Plain Language Summary: The diurnal cycle of submesoscale motions has been explored in high‐resolution simulations and observations, but the understanding for the variability of associated overturning instability remains limited. Here, we present new observational evidence of the diurnal variability of forced overturning instabilities using high‐resolution data from a 3‐month glider array observation. The results show that this diurnal variability is primarily modulated by surface heat fluxes rather than wind friction. Among the identified instabilities, symmetric instability is significantly energized by the surface cooling and tends to drive stronger submesoscale restratification at night. Given their frequent occurrence in the upper ocean, enhanced submesoscale vertical exchange due to nighttime surface cooling may play an important role in oceanic mixed layer restratification, potentially modulating the climate system and marine ecosystem. Key Points: New evidence for the diurnal variability of mixed layer (ML) overturning instabilities is provided by a glider array observationSurface heat fluxes are found to primarily modulate the diurnal variability of ML overturning cells in the realistic oceanMore than 60% of observed submesoscale overturning cells are energized by nighttime surface cooling and act to restratify the ML [ABSTRACT FROM AUTHOR]

The global expansion of photovoltaic (PV) power plants, especially in ecologically fragile regions like the Gobi Desert, highlights the suitability of such areas for large-scale PV development. The most direct impact of PV development in the Gobi Desert is temperature change that results from the land-use-induced albedo changes; however, the detailed and systemic understanding of the effects of PV expansion on land surface temperature remains limited. This study focuses on the 16 largest PV plants in the Chinese Gobi Desert, utilizing remote sensing data to assess their effects on land surface temperature. Our result showed a cooling effect during the daytime (−0.69 ± 0.10 °C), but a warming effect during the nighttime (0.23 ± 0.05 °C); the overall effect on the daily mean was a cooling effect (−0.22 ± 0.05 °C). Seasonal variations were observed, with the most significant cooling effect in autumn and the weakest in summer. The PV area was the most significant factor which influenced the temperature variation across PV plants. Our findings enrich our understanding of the environmental effects arising from the construction of PV plants and provide vital information for the design and management of increasingly renewable electricity systems globally. [ABSTRACT FROM AUTHOR]

This study characterizes the variability in different parameters using high-frequency ground-based instruments, i.e., ceilometer and Micro Rain Radar (MRR), on a diurnal scale installed at the Indian Institute of Technology Bhubaneswar, Odisha, India. The study evaluates cloud base height (CBH) and boundary layer height (BLH) to understand their role in influencing convection from liquid water content (LWC), rain rate, radar reflectivity, and fall velocity over a tropical location for different seasons on a diurnal scale. The data retrieved from these surface-based instruments are segregated into four different seasons, i.e., pre-monsoon, monsoon, post-monsoon, and winter, for 2019 and 2020. It is noted that the atmospheric processes influencing convection and associated rainfall over the study location differ for different seasons. The frequency distribution of different types of clouds depending on their vertical levels, i.e., low-level clouds (LLC), mid-level clouds (MLC), and high-level clouds (HLC), during different seasons revealed a high occurrence of low- to mid-level clouds in pre-monsoon and post-monsoon seasons, mid-level clouds in the monsoon season, and low-level clouds in the winter season. The results also illustrate that the rainfall during different seasons largely depends on the types of clouds, i.e., LLC, MLC, and HLC, as detected from the CBH layers, which contribute to convection and rainfall over the study location. It is also revealed that the boundary layer processes in convection and rainfall influence the evolution of BLH during different seasons. Further, the study compares model skills in verifying boundary layer height and rainfall against surface-based observations. Besides characterizing the diurnal variability in these parameters on a daily scale, the study also elucidates the relationship between the cloud types and BLH. The results indicate that LLC occurrences were positively related to BLH during the pre-monsoon and monsoon seasons in 2019 and 2020. In contrast, a negative correlation is observed for cloud types MLC and HLC with BLH for the rest of the seasons of 2019 and 2020. Also, during post-monsoon and monsoon, distinct signatures of deep convection are noted over the study region, suggesting the influence of the boundary layer on MLC and HLC. The results from radar reflectivity and fall velocity during the monsoon and post-monsoon season support the influence of MLC and HLC on deep convection over the region. The diurnal variation in the observed parameters on a seasonal scale will help in understanding the role of various atmospheric parameters and processes in convection and associated rainfall over a tropical location and can provide necessary verification skills for weather and climate regional models against observations. [ABSTRACT FROM AUTHOR]

Accurate and consistent observations of diurnal variability of sea surface temperature (SST DV) and its impact on air–sea heat fluxes over large areas for extended periods are challenging due to their short time scale and wide coverage. The hourly gap-free SSTs generated from Japan Aerospace Exploration Agency-Japan Agency for Marine–Earth Science and Technology (JAXA-JAMSTEC) are input to the COARE3.5 bulk flux algorithm to investigate the impact of SST DV on air–sea heat fluxes over the Northwest Pacific Ocean (NWPO). The main results are as follows. (1) The JAXA-JAMSTEC SSTs were found to be in good agreement with the buoy observations on SST DV with a very slight negative bias of −0.007 °C and a root mean square error of 0.018 °C. (2) The case study conducted on 26 June 2020 showed that the fluxes' diurnal amplitudes were about 30–50 W   m − 2 , and evolution was in agreement with SST DV. (3) The average impact of SST DV on heat fluxes was 2.93 W   m − 2 over the subtropical NWPO, decreasing from southeast to northwest and from low to high latitudes, and showing a clear seasonal cycle during 2019–2022. This research highlights the need to consider SST DV for accurate estimation of heat fluxes, which is crucial for climate and atmospheric studies. [ABSTRACT FROM AUTHOR]

Abstract The diurnal variability of mixed layer (ML) overturning instabilities remains poorly understood due to the challenge in capturing their rapid evolutions across large spatiotemporal ranges. Using high‐resolution data from 52 gliders in the South China Sea, we examine the diurnal modulations of ML overturning instabilities. The results of the 3‐month field observation show that negative potential vorticity occupies ∼16% of the ML and facilitates several types of forced overturning instabilities, especially symmetric instability (SI). Surface heat fluxes are identified to primarily modulate the diurnal variability of these overturning cells, where nighttime surface cooling is found to energize SI with an ∼2‐hr phase lag. As a result, over 60% of forced submesoscale overturning cells tend to restratify the ML at night. These findings quantitatively highlight the modulation of diabatic atmospheric forcing in submesoscale restratification, which should be considered in submesoscale parameterizations of ocean and climate models.

Projections of future climate are sensitive to the representation of upper-ocean diurnal variability, including the diurnal cycle of winds. Two different methods suitable for time series with missing data are used here to characterize how observed diurnal winds vary over the year. One is based on diurnal composites of mooring data, and the other is based on harmonic analysis via a least squares fit and is able to isolate annual (i.e., 1 cycle per year) modulation of diurnal variability. Results show that the diurnal amplitude in meridional winds is larger than in zonal winds and peaks in the tropical Pacific, where diurnal variability in zonal winds is overall weaker compared to other basins. Furthermore, the amplitude and phasing of diurnal winds in the tropical oceans are not uniform in time, with overall larger differences through the year in the meridional component of tropical winds. Estimating the annual modulation of the diurnal signal implies resolving both the diurnal energy peak and also the modulation of this peak by the annual cycle. This leads to a recommendation for sampling at least 6 times per day and for a duration of at least 3 years.

This study characterizes cancer and non-cancer risks due to inhalation exposure to volatile organic compounds (VOCs) in a border city of Windsor in southern Ontario, Canada, using hourly ambient concentrations collected from 17 November 2021 to 17 March 2023. The total incremental lifetime cancer risk (CR) due to benzene and ethylbenzene is 4.33 × 10−6, which is in the acceptable risk range of 1 × 10−6 to 1 × 10−4 used by the USEPA. The CR was higher in winter (5.20 × 10−6), followed by fall (4.32 × 10−6), spring (3.86 × 10−6), and summer (2.96 × 10−6), all in the acceptable range. The total chronic non-cancer risk (Hazard Quotient, HQ) of inhalation exposure to 16 VOCs was 0.0488, with a higher value in fall (0.0571), followed by winter (0.0464), and lower in spring (0.0454) and summer (0.0451), all in the safe level of below HQ = 1 used by the USEPA. The hazard index (HI) by organs was higher for the nervous system (0.0213), followed by the hematologic system and immune system (0.0165 each), but much lower for the other five target organs, i.e., the liver/kidney (1.52 × 10−4), developmental system (3.38 × 10−4), endocrine system and urinary system (2.82 × 10−4 each), and respiratory system (9.70 × 10−5). Similar hour-of-day trends were observed in the total CR, total HQ, and HI by organs with higher values in the early morning hours of 5:00–8:00 and lower values during 12:00 to 15:00. Benzene was the major contributor to both total CR (89%) and total HQ (34%) due to its high toxicity and high concentrations. Benzene, toluene, ethylbenzene, and xylenes (BTEX) contributed 100% of the total CR and 51% of the total HQ. Further, BTEX is the sole contributor to the HI for the hematologic system and immune system and the major contributor to the HI for the nervous system (39%) and developmental system (55%). Higher cancer and non-cancer risks were associated with the airmass from the east, southeast, and southwest of Windsor.

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Abstract Background The negative effect of air pollution on human health is widely reported in recent literature. It typically involves urbanized areas where the population is concentrated and where most primary air pollutants are produced. A comprehensive health risk assessment is therefore of strategic importance for health authorities. Methods In this study we propose a methodology to perform an indirect and retrospective health risk assessment of all-cause mortality associated with long-term exposure to particulate matter less than 2.5 microns (PM2.5), nitrogen dioxide (NO2) and ozone (O3) in a typical Monday to Friday working week. A combination of satellite-based settlement data, model-based air pollution data, land use, demographics and regional scale mobility, allowed to examine the effect of population mobility and pollutants daily variations on the health risk. A Health Risk Increase (HRI) metric was derived on the basis of three components: hazard, exposure and vulnerability, utilizing the relative risk values from the World Health Organization. An additional metric, the Health Burden (HB) was formulated, which accounts for the total number of people exposed to a certain risk level. Results The effect of regional mobility patterns on the HRI metric was assessed, resulting in an increased HRI associated with all three stressors when considering a dynamic population compared to a static one. The effect of diurnal variation of pollutants was only observed for NO2 and O3. For both, the HRI metric resulted in significantly higher values during night. Concerning the HB parameter, we identified the commuting flows of the population as the main driver in the resulting metric. Conclusions This indirect exposure assessment methodology provides tools to support policy makers and health authorities in planning intervention and mitigation measures. The study was carried out in Lombardy, Italy, one of the most polluted regions in Europe, but the incorporation of satellite data makes our approach valuable for studying global health.

The global expansion of photovoltaic (PV) power plants, especially in ecologically fragile regions like the Gobi Desert, highlights the suitability of such areas for large-scale PV development. The most direct impact of PV development in the Gobi Desert is temperature change that results from the land-use-induced albedo changes; however, the detailed and systemic understanding of the effects of PV expansion on land surface temperature remains limited. This study focuses on the 16 largest PV plants in the Chinese Gobi Desert, utilizing remote sensing data to assess their effects on land surface temperature. Our result showed a cooling effect during the daytime (−0.69 ± 0.10 °C), but a warming effect during the nighttime (0.23 ± 0.05 °C); the overall effect on the daily mean was a cooling effect (−0.22 ± 0.05 °C). Seasonal variations were observed, with the most significant cooling effect in autumn and the weakest in summer. The PV area was the most significant factor which influenced the temperature variation across PV plants. Our findings enrich our understanding of the environmental effects arising from the construction of PV plants and provide vital information for the design and management of increasingly renewable electricity systems globally.

Background: The negative effect of air pollution on human health is widely reported in recent literature. It typically involves urbanized areas where the population is concentrated and where most primary air pollutants are produced. A comprehensive health risk assessment is therefore of strategic importance for health authorities. Methods: In this study we propose a methodology to perform an indirect and retrospective health risk assessment of all-cause mortality associated with long-term exposure to particulate matter less than 2.5 microns (PM2.5), nitrogen dioxide (NO2) and ozone (O3) in a typical Monday to Friday working week. A combination of satellite-based settlement data, model-based air pollution data, land use, demographics and regional scale mobility, allowed to examine the effect of population mobility and pollutants daily variations on the health risk. A Health Risk Increase (HRI) metric was derived on the basis of three components: hazard, exposure and vulnerability, utilizing the relative risk values from the World Health Organization. An additional metric, the Health Burden (HB) was formulated, which accounts for the total number of people exposed to a certain risk level. Results: The effect of regional mobility patterns on the HRI metric was assessed, resulting in an increased HRI associated with all three stressors when considering a dynamic population compared to a static one. The effect of diurnal variation of pollutants was only observed for NO2 and O3. For both, the HRI metric resulted in significantly higher values during night. Concerning the HB parameter, we identified the commuting flows of the population as the main driver in the resulting metric. Conclusions: This indirect exposure assessment methodology provides tools to support policy makers and health authorities in planning intervention and mitigation measures. The study was carried out in Lombardy, Italy, one of the most polluted regions in Europe, but the incorporation of satellite data makes our approach valuable for studying global health. [ABSTRACT FROM AUTHOR]

Introduction: Fatigue is the most common and debilitating symptom experienced by cancer patients undergoing chemotherapy (CTX). Prediction of symptom severity can assist clinicians to identify high-risk patients and provide education to decrease symptom severity. The purpose of this study was to predict the severity of morning fatigue in the week following the administration of CTX. Methods: Outpatients (n = 1217) completed questionnaires 1 week prior to and 1 week following administration of CTX. Morning fatigue was measured using the Lee Fatigue Scale (LFS). Separate prediction models for morning fatigue severity were created using 157 demographic, clinical, symptom, and psychosocial adjustment characteristics and either morning fatigue scores or individual fatigue item scores. Prediction models were created using two regression and five machine learning approaches. Results: Elastic net models provided the best fit across all models. For the EN model using individual LFS item scores, two of the 13 individual LFS items (i.e., “worn out,” “exhausted”) were the strongest predictors. Conclusions: This study is the first to use machine learning techniques to accurately predict the severity of morning fatigue from prior to through the week following the administration of CTX using total and individual item scores from the Lee Fatigue Scale (LFS). Our findings suggest that the language used to assess clinical fatigue in oncology patients is important and that two simple questions may be used to predict morning fatigue severity. [ABSTRACT FROM AUTHOR]

The main objective of the current study was to investigate the effect of time of day on visual and auditory, short-term memory (STM), and long-term memory (LTM) distortions using a hybrid Deese-Roediger-McDermott procedure. In Experiment 1, we used semantically related words, whereas in Experiment 2 – words were characterized by phonological similarity. The results showed a relationship between modality and types of stimuli. In STM, more semantic errors were found in the evening for items presented visually and more errors following auditory presentation for phonologically similar words. In LTM, the analysis revealed a higher rate of semantic distortions in the evening hours for auditorily presented words. For words with phonological similarity, we observed more errors in the evening without the effect of modality. The results support the hypothesis that more reliance is placed on elaborative processing in the evening and more on maintenance processing in the morning; however, this is not modality invariant. [ABSTRACT FROM AUTHOR]

Using measurements from the Geostationary Ocean Color Imager (GOCI) on the Communication, Ocean, and Meteorological Satellite (COMS), we characterize and quantify some advantages and applications of the satellite geostationary measurements, compared with those of the polar-orbiting satellites. With eight daily measurements in the western Pacific Ocean, the average GOCI daily coverage of ocean color retrievals reached ∼43.81%, compared to ∼21.77% from the Visible Infrared Imaging Radiometer Suite (VIIRS). The GOCI-measured ocean property data, such as normalized water-leaving radiance [nLw(λ)] and diffuse attenuation coefficient at 490 nm [Kd(490)], show significant diurnal variability over the region, particularly over highly turbid coastal regions. It is noted that GOCI-derived nLw(λ) spectra and Kd(490) in the region have been compared with those from VIIRS in 2012, 2016, and 2019, and shown consistent results (within ∼5–10%). Using the GOCI daily statistical results from its hourly data, i.e., standard deviations (STDs) and coefficient of variations (CVs) of nLw(λ) and Kd(490), the diurnal variability has been demonstrated and quantified. Over turbid coastal regions, STDs and CVs of nLw(λ) at GOCI 555 and 660 nm bands are important for characterizing diurnal variability, while for open oceans STDs and CVs of nLw(λ) at 412, 443, and 555 nm are useful. Specifically, using the four GOCI daily examples in 2019 on January 24, May 21, August 16, and November 15, we have carried out quantitative analyses for understanding regional diurnal variations. In addition, using the GOCI measurements from 2011 to 2020 in the region, hourly climatology Kd(490) data in four seasons and quantitative results are derived and presented. Results show important characteristics in ocean diurnal variabilities over this highly dynamic and complex western Pacific Ocean region. Indeed, the regional diurnal variability has strong spatial and temporal (seasonal) dependences, which are mostly related to regional ocean optical and bio-optical properties.

Accurate and consistent observations of diurnal variability of sea surface temperature (SST DV) and its impact on air–sea heat fluxes over large areas for extended periods are challenging due to their short time scale and wide coverage. The hourly gap-free SSTs generated from Japan Aerospace Exploration Agency-Japan Agency for Marine–Earth Science and Technology (JAXA-JAMSTEC) are input to the COARE3.5 bulk flux algorithm to investigate the impact of SST DV on air–sea heat fluxes over the Northwest Pacific Ocean (NWPO). The main results are as follows. (1) The JAXA-JAMSTEC SSTs were found to be in good agreement with the buoy observations on SST DV with a very slight negative bias of −0.007 °C and a root mean square error of 0.018 °C. (2) The case study conducted on 26 June 2020 showed that the fluxes’ diurnal amplitudes were about 30–50 W m−2, and evolution was in agreement with SST DV. (3) The average impact of SST DV on heat fluxes was 2.93 W m−2 over the subtropical NWPO, decreasing from southeast to northwest and from low to high latitudes, and showing a clear seasonal cycle during 2019–2022. This research highlights the need to consider SST DV for accurate estimation of heat fluxes, which is crucial for climate and atmospheric studies.

Geostationary Ocean Colour Imager (GOCI) provides ocean colour products for monitoring ecosystem dynamics and assessing spatiotemporal changes. However, producing reliable satellite-based product estimates remains challenging in optically complex coastal waters, and bio-optics algorithms must be assessed. To date, assessments of satellite products have been analysed based on clear, natural waters. In this study, we assume stable waters that express little to no diurnal variability due to biological or physical processes in coastal water. Then, a suitable bio-optical algorithm with the lowest uncertainty is selected. The Tassan (MS) algorithm proposed in 2016 provided the appropriate representations of the temporal variation in chlorophyll in the results. The uncertainty of chlorophyll a estimated at the Mooring site located at the Yangtze River mouth and at the Ieodo site located off the coast of the Tsushima Strait were less than 14.5%, and the maximum uncertainty at the Socheongcho site, which was close to the Korean Peninsula, was 28.7%. [ABSTRACT FROM AUTHOR]

Ambient fine particulate matter (PM2.5) levels in Windsor, Ontario, Canada, are impacted by local emissions and regional/transboundary transport input and also attributable to secondary formation. PM2.5-bound elements were monitored hourly in Windsor from April to October 2021. Observed concentrations of the elements were generally comparable to historical measurements at urban sites in Ontario. A clear diurnal pattern was observed for most of the elements, i.e., high in the morning and low in the afternoon, mostly related to evolution of atmospheric mixing heights and local anthropogenic activities. Conversely, sulfur showed elevated levels in the afternoon, suggesting conversion of gaseous sulfur dioxide to particulate sulphate was enhanced by increased ambient temperatures. Five source factors were resolved using the US EPA positive matrix factorization model, including three traffic-related sources (i.e., vehicular exhaust, crustal dust, and vehicle tire and brake wear factors) and two industrial sources (i.e., coal/heavy oil burning and metal processing factors). Overall, the three traffic-related sources were mostly local and contributed to 47% of the total elemental concentrations, while the two industrial sources may originate from regional/transboundary sources and contributed to 53%. Measures to control both local traffic emissions and regional/transboundary industrial sources would help reduce levels of PM2.5-bound elements in Windsor. [ABSTRACT FROM AUTHOR]

First observations on the vertical structure of diurnal variability of water vapour in the lower and middle atmosphere using 13 years of COSMIC-1 and 18 years of SABER observations over the Asian summer monsoon region are presented in this paper. The most significant and new observation is that the middle stratospheric water vapour (SWV) enhancement is observed between 9 and 18 LT, whereas it is between 6 and 15 LT near tropopause in all the seasons. The diurnal amplitude of water vapour near tropopause is between 0.3 and 0.4 ppmv. Bimodal peaks are found in the diurnal amplitude of SWV, maximizing between 25 and 30 km (~ 0.4 ppmv), and between 45 and 50 km (~ 0.6 ppmv). The analysis reveals that the diurnal variability in the lower SWV is controlled by the tropical tropopause temperature, whereas the middle and upper SWV is primarily controlled by methane oxidation. The results are presented and discussed in the light of present understanding. [ABSTRACT FROM AUTHOR]

Ocean acidification (OA) is expected to modify the structure and function of coral reef ecosystems by reducing calcification, increasing bioerosion, and altering the physiology of many marine organisms. Much of our understanding of these relationships is based on experiments with static OA treatments, although evidence suggests that the magnitude of diurnal fluctuations in carbonate chemistry may modulate the calcification response to OA. These light‐mediated swings in seawater pH are projected to become more extreme with OA, yet their impact on bioerosion remains unknown. We evaluated the influence of diurnal carbonate chemistry variability on the bioerosion rates of two Caribbean sponges: the zooxanthellate Cliona varians and azooxanthellate Cliothosa delitrix. Replicate fragments from multiple colonies of each species were exposed to four precisely controlled pH treatments: contemporary static (8.05 ± 0.00; mean pH ± diurnal pH oscillation), contemporary variable (8.05 ± 0.10), future OA static (7.80 ± 0.00), and future OA variable (7.80 ± 0.10). Significantly enhanced bioerosion rates, determined using buoyant weight measurements, were observed under more variable conditions in both the contemporary and future OA scenarios for C. varians, whereas the same effect was only apparent under contemporary pH conditions for C. delitrix. These results indicate that variable carbonate chemistry has a stimulating influence on sponge bioerosion, and we hypothesize that bioerosion rates evolve non‐linearly as a function of pCO2 resulting in different magnitudes and directions of rate enhancement/reduction between day and night, even with an equal fluctuation around the mean. This response appeared to be intensified by photosymbionts, evident by the consistently higher percent increase in bioerosion rates for photosynthetic C. varians across all treatments. These findings further suggest that more variable natural ecosystems may presently experience elevated sponge bioerosion rates and that the heightened impact of OA enhanced bioerosion on reef habitat could occur sooner than prior predictions. [ABSTRACT FROM AUTHOR]

Water bodies that serve as sources of drinking or recreational water are routinely monitored for fecal indicator bacteria (FIB) by state and local agencies. Exceedances of monitoring thresholds set by those agencies signal likely elevated human health risk from exposure, but FIB give little information about the potential source of contamination. To improve our understanding of how within-day variation could impact monitoring data interpretation, we conducted a study at two sites along the Chattahoochee River that varied in their recreational usage and adjacent land-use (natural versus urban), collecting samples every 30 min over one 24-h period. We assayed for three types of microbial indicators: FIB (total coliforms and Escherichia coli); human fecal-associated microbial source tracking (MST) markers (crAssphage and HF183/BacR287); and a suite of clinically relevant antibiotic resistance genes (ARGs; blaCTX-M, blaCMY, MCR, KPC, VIM, NDM) and a gene associated with antibiotic resistance (intl1). Mean levels of FIB and clinically relevant ARGs (blaCMY and KPC) were similar across sites, while MST markers and intI1 occurred at higher mean levels at the natural site. The human-associated MST markers positively correlated with antibiotic resistant-associated genes at both sites, but no consistent associations were detected between culturable FIB and any molecular markers. For all microbial indicators, generalized additive mixed models were used to examine diurnal variability and whether this variability was associated with environmental factors (water temperature, turbidity, pH, and sunlight). We found that FIB peaked during morning and early afternoon hours and were not associated with environmental factors. With the exception of HF183/BacR287 at the urban site, molecular MST markers and intI1 exhibited diurnal variability, and water temperature, pH, and turbidity were significantly associated with this variability. For blaCMY and KPC, diurnal variability was present but was not correlated with environmental factors. These results suggest that differences in land use (natural or urban) both adjacent and upstream may impact overall levels of microbial contamination. Monitoring agencies should consider matching sample collection times with peak levels of target microbial indicators, which would be in the morning or early afternoon for the fecal associated indicators. Measuring multiple microbial indicators can lead to clearer interpretations of human health risk associated with exposure to contaminated water. [ABSTRACT FROM AUTHOR]

The article studies the data from a weekly campaign devoted to the study of the elemental composition of PM10 in a selected receptor, in a suburban area (Mazowieckie Voivodeship). The sampling point was located at the intersection of main roads and in the vicinity of a typical single-family housing, not far from the electrified Warsaw-Białystok railway line and a small heating plant. The research was carried out in the summer season, in order to minimize the impact of municipal emissions on the concentrations and elemental composition of PM10. A Horiba PX-375 X-ray fluorescence spectrometer was used to measure the one-hour concentrations of elements related to PM10. On the basis of the obtained results, the enrichment factors for PM10 in the analyzed elements (EF) were calculated and the principal components analysis (PCA) was performed. It was found that although the elemental composition of PM10 in all tested time intervals was noticeably influenced by the emissions from transport, the municipal emissions had a significant impact on the elemental composition, especially those related to coal combustion, and thus the concentration of PM10 during the study period. It seems that the possibility of observing the influence of all relevant sources on the composition and concentration of PM10 was possible owing to the use of hourly-averaged measurements of the elemental composition of PM10. In the case of daily averaged measurements, in a receptor with such PM10 elemental profile, it would be impossible to determine the periods, in which specific - qualitatively completely different - emission sources dominate. [ABSTRACT FROM AUTHOR]

Water bodies that serve as sources of drinking or recreational water are routinely monitored for fecal indicator bacteria (FIB) by state and local agencies. Exceedances of monitoring thresholds set by those agencies signal likely elevated human health risk from exposure, but FIB give little information about the potential source of contamination. To improve our understanding of how within-day variation could impact monitoring data interpretation, we conducted a study at two sites along the Chattahoochee River that varied in their recreational usage and adjacent land-use (natural versus urban), collecting samples every 30 min over one 24-h period. We assayed for three types of microbial indicators: FIB (total coliforms and Escherichia coli); human fecal-associated microbial source tracking (MST) markers (crAssphage and HF183/BacR287); and a suite of clinically relevant antibiotic resistance genes (ARGs; blaCTX-M, blaCMY, MCR, KPC, VIM, NDM) and a gene associated with antibiotic resistance (intl1). Mean levels of FIB and clinically relevant ARGs (blaCMY and KPC) were similar across sites, while MST markers and intI1 occurred at higher mean levels at the natural site. The human-associated MST markers positively correlated with antibiotic resistant-associated genes at both sites, but no consistent associations were detected between culturable FIB and any molecular markers. For all microbial indicators, generalized additive mixed models were used to examine diurnal variability and whether this variability was associated with environmental factors (water temperature, turbidity, pH, and sunlight). We found that FIB peaked during morning and early afternoon hours and were not associated with environmental factors. With the exception of HF183/BacR287 at the urban site, molecular MST markers and intI1 exhibited diurnal variability, and water temperature, pH, and turbidity were significantly associated with this variability. For blaCMY and KPC, diurnal variability was present but was not correlated with environmental factors. These results suggest that differences in land use (natural or urban) both adjacent and upstream may impact overall levels of microbial contamination. Monitoring agencies should consider matching sample collection times with peak levels of target microbial indicators, which would be in the morning or early afternoon for the fecal associated indicators. Measuring multiple microbial indicators can lead to clearer interpretations of human health risk associated with exposure to contaminated water.

Coastal ecosystems are increasingly threatened by anthropogenic impacts, particularly from land-based activities that drive eutrophication. This research investigated eutrophication and the unique challenges facing southern hemisphere coastal ecosystems. We used a mesocosm study to measure the influence of a macroalga (Rhizoclonium riparium) and a floating macrophyte (Pistia stratiotes), on diurnal pH variability. Diurnal pH variability was more pronounced in the presence of macroalgae due to the direct release of metabolic byproducts into the water column during photosynthesis and respiration. In contrast, floating macrophyte treatments had lower diurnal pH variability, as metabolic byproducts are released into the atmosphere through floating foliage. Floating macrophytes influenced overall water column pH levels, resulting in an acidification effect, becoming more pronounced as macrophyte biomass increased. The study highlighted the importance of nutrient management and its association with macrophytes, to preserve the delicate balance of estuaries, and ensure the sustainable functioning of these critical ecosystems. Further in situ research is recommended to validate and expand on the mesocosm findings. [Display omitted] • Macrophytes influence estuary water column pH levels. • Floating macrophytes decrease pH and submerged macrophytes increase pH. • Diurnal pH variability is more pronounced in submerged macroalgae. • Floating macrophytes exhibit lower diurnal variability. [ABSTRACT FROM AUTHOR]

Upper ocean processes play a key role in air-sea coupling, with variability on both short and long time scales. The diurnal cycle associated with diurnal solar insolation and nighttime cooling, may act, along with stochastic wind variability, on upper ocean temperatures and stratification resulting in a diurnal warm layer and a nonlinear rectified effect on longer time scales. This study describes diurnal changes in upper ocean temperature for a location in the equatorial Indian Ocean, using observations from the Dynamics of the Madden-Julian Oscillation field campaign, a high vertical resolution 1-D process model, and a diurnal cycling scheme. Solar forcing is the main driver of diurnal variability in upper ocean temperature and stratification. Yet except during nighttime convection, winds with variability on the order of hours (here referred to as “wind gusts”) regulate how fast surface water is mixed to greater depths when daily mean winds are weak. Wind gusts are much stronger than diurnal winds. Even using stochastic wind gusts but no diurnal winds as input in a 1-D process model yields an estimate of diurnal temperature that compares well with observations. A new version of the Large and Caron (2015) scheme (LC2015) provides an estimate of upper ocean diurnal temperature that is consistent with observations. LC2015 has the advantage of being suitable for implementation in a climate model, with the goal to improve SST estimates, hence the simulated heat flux at the air-sea interface. Yet LC2015 is not very sensitive to the inclusion or omission of the high-frequency component of the wind.

Upper ocean processes play a key role in air-sea coupling, with variability on both short and long time scales. The diurnal cycle associated with diurnal solar insolation and nighttime cooling, may act, along with stochastic wind variability, on upper ocean temperatures and stratification resulting in a diurnal warm layer and a nonlinear rectified effect on longer time scales. This study describes diurnal changes in upper ocean temperature for a location in the equatorial Indian Ocean, using observations from the Dynamics of the Madden-Julian Oscillation field campaign, a high vertical resolution 1-D process model, and a diurnal cycling scheme. Solar forcing is the main driver of diurnal variability in upper ocean temperature and stratification. Yet except during nighttime convection, winds with variability on the order of hours (here referred to as “wind gusts”) regulate how fast surface water is mixed to greater depths when daily mean winds are weak. Wind gusts are much stronger than diurnal winds. Even using stochastic wind gusts but no diurnal winds as input in a 1-D process model yields an estimate of diurnal temperature that compares well with observations. A new version of the Large and Caron (2015) scheme (LC2015) provides an estimate of upper ocean diurnal temperature that is consistent with observations. LC2015 has the advantage of being suitable for implementation in a climate model, with the goal to improve SST estimates, hence the simulated heat flux at the air-sea interface. Yet LC2015 is not very sensitive to the inclusion or omission of the high-frequency component of the wind.

Fatigue, a highly prevalent and distressing symptom during chemotherapy (CTX), demonstrates diurnal and interindividual variability in severity. Little is known about the associations between variations in genes involved in inflammatory processes and morning and evening fatigue severity during CTX. The purposes of this study, in a sample of oncology patients (N=543) with breast, gastrointestinal (GI), gynecological (GYN), or lung cancer who received two cycles of CTX, were to determine whether variations in genes involved in inflammatory processes were associated with inter-individual variability in initial levels as well as in the trajectories of morning and evening fatigue. Patients completed the Lee Fatigue Scale to determine morning and evening fatigue severity a total of six times over two cycles of CTX. Using a whole exome array, 309 single nucleotide polymorphisms SNPs among the 64 candidate genes that passed all quality control filters were evaluated using hierarchical linear modeling (HLM). Based on the results of the HLM analyses, the final SNPs were evaluated for their potential impact on protein function using two bioinformational tools. The following inflammatory pathways were represented: chemokines (3 genes); cytokines (12 genes); inflammasome (11 genes); Janus kinase/signal transducers and activators of transcription (JAK/STAT, 10 genes); mitogen-activated protein kinase/jun amino-terminal kinases (MAPK/JNK, 3 genes); nuclear factor-kappa beta (NFkB, 18 genes); and NFkB and MAP/JNK (7 genes). After controlling for self-reported and genomic estimates of race and ethnicity, polymorphisms in six genes from the cytokine (2 genes); inflammasome (2 genes); and NFkB (2 genes) pathways were associated with both morning and evening fatigue. Polymorphisms in six genes from the inflammasome (1 gene); JAK/STAT (1 gene); and NFkB (4 genes) pathways were associated with only morning fatigue. Polymorphisms in three genes from the inflammasome (2 genes) and the NFkB (1 gene) pathways were associated with only evening fatigue. Taken together, these findings add to the growing body of evidence that suggests that morning and evening fatigue are distinct symptoms.

Surface urban heat islands (SUHI) translate the difference in surface temperature between urban and surrounding rural regions. This study makes use of geostationary remote sensing data (Meteosat Second Generation) rather than polar orbiting satellites, taking advantage of its higher temporal resolution. Three cities were selected: Paris, Madrid and Milan. This allowed studying both the seasonal and diurnal cycles of SUHI. The SUHI is here computed with reference to the agricultural and forest rural land covers, and the two combined. We found that for a generic rural background, the SUHI maximum occurs at 12/20/12 UTC in spring/spring/summer with values of 3.1/1.6/4.0 °C for Paris/Madrid/Milan. Secondary peaks of SUHI are also sometimes found during the nighttime in the cities of Paris and Milan. Our results highlight the need for understanding the diurnal variability of SUHI throughout the year, considering the different city surroundings. It is found that for the same urban temperature, different SUHI intensities can occur when varying the rural cover reference. Also, for the same urban temperatures, neither SUHI intensity, nor its diurnal cycle is constant throughout the year, emphasizing the need for high temporal resolution datasets in SUHI studies. • Geostationary satellites allow the study of both seasonal and diurnal cycles of surface urban heat islands at an hourly rate. • Diurnal pattern of surface urban heat island is not constant throughout the year. • For the same urban temperature, different SUHI intensities can occur when varying the rural cover reference. [ABSTRACT FROM AUTHOR]

Ambient fine particulate matter (PM2.5) levels in Windsor, Ontario, Canada, are impacted by local emissions and regional/transboundary transport input and also attributable to secondary formation. PM2.5-bound elements were monitored hourly in Windsor from April to October 2021. Observed concentrations of the elements were generally comparable to historical measurements at urban sites in Ontario. A clear diurnal pattern was observed for most of the elements, i.e., high in the morning and low in the afternoon, mostly related to evolution of atmospheric mixing heights and local anthropogenic activities. Conversely, sulfur showed elevated levels in the afternoon, suggesting conversion of gaseous sulfur dioxide to particulate sulphate was enhanced by increased ambient temperatures. Five source factors were resolved using the US EPA positive matrix factorization model, including three traffic-related sources (i.e., vehicular exhaust, crustal dust, and vehicle tire and brake wear factors) and two industrial sources (i.e., coal/heavy oil burning and metal processing factors). Overall, the three traffic-related sources were mostly local and contributed to 47% of the total elemental concentrations, while the two industrial sources may originate from regional/transboundary sources and contributed to 53%. Measures to control both local traffic emissions and regional/transboundary industrial sources would help reduce levels of PM2.5-bound elements in Windsor.

Manual measurements of nitrous oxide (N2O) emissions with static chambers are commonly practised. However, they generally do not consider the diurnal variability of N2O flux, and little is known about the patterns and drivers of such variability. We systematically reviewed and analysed 286 diurnal data sets of N2O fluxes from published literature to (i) assess the prevalence and timing (day or night peaking) of diurnal N2O flux patterns in agricultural and forest soils, (ii) examine the relationship between N2O flux and soil temperature with different diurnal patterns, (iii) identify whether non‐diurnal factors (i.e. land management and soil properties) influence the occurrence of diurnal patterns and (iv) evaluate the accuracy of estimating cumulative N2O emissions with single‐daily flux measurements. Our synthesis demonstrates that diurnal N2O flux variability is a widespread phenomenon in agricultural and forest soils. Of the 286 data sets analysed, ~80% exhibited diurnal N2O patterns, with ~60% peaking during the day and ~20% at night. Contrary to many published observations, our analysis only found strong positive correlations (R > 0.7) between N2O flux and soil temperature in one‐third of the data sets. Soil drainage property, soil water‐filled pore space (WFPS) level and land use were also found to potentially influence the occurrence of certain diurnal patterns. Our work demonstrated that single‐daily flux measurements at mid‐morning yielded daily emission estimates with the smallest average bias compared to measurements made at other times of day, however, it could still lead to significant over‐ or underestimation due to inconsistent diurnal N2O patterns. This inconsistency also reflects the inaccuracy of using soil temperature to predict the time of daily average N2O flux. Future research should investigate the relationship between N2O flux and other diurnal parameters, such as photosynthetically active radiation (PAR) and root exudation, along with the consideration of the effects of soil moisture, drainage and land use on the diurnal patterns of N2O flux. The information could be incorporated in N2O emission prediction models to improve accuracy. [ABSTRACT FROM AUTHOR]

The sub-daily variability of aerosols affects the estimates of daily mean aerosol loading. However, large spatial scale estimates of their climate effects are mostly based on snapshots from low orbit satellites that may bias the mean estimate for daily, monthly, or annual timescales. In this study, an attempt is made to estimate the magnitude of such bias based on ground and satellite-based datasets. Using ground-based measurements, we show an apparent asymmetry (of the order of 10–50%) in the sub-daily variability of aerosol loading over the Indian region. For the first time, it is reported that this sub-daily variability has a spatial pattern with an increasing amplitude toward the east of the subcontinent. We also find this variability in aerosol loading is well-captured by the satellites but with a lower amplitude. Our study shows that such differences could alter the annual surface radiative forcing estimates by more than ∼15 W m−2 over this region. We find that NASA’s Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2), a state-of-the-art model-based chemical reanalysis, is unable to capture these sub-daily variabilities. This implies that both model and satellite-based radiative forcing estimates for large spatial scales should improve aerosol sub-daily information/variabilities for obtaining reliable radiative forcing estimates.

© 2014. American Geophysical Union. All Rights Reserved. Observations from 35 tropical moorings are used to characterize the diurnal cycle in salinity at 1 m depth. The amplitude of diurnal salinity anomalies is up to 0.01 psu and more typically ∼0.005 psu. Diurnal variations in precipitation and vertical entrainment appear to be the dominant drivers of diurnal salinity variability, with evaporation also contributing. Areas where these processes are strong are expected to have relatively strong salinity cycles: the eastern Atlantic and Pacific equatorial regions, the southwestern Bay of Bengal, the Amazon outflow region, and the Indo-Pacific warm pool. We hypothesize that salinity anomalies resulting from precipitation and evaporation are initially trapped very near the surface and may not be observed at the 1 m instrument depths until they are mixed downward. As a result, the pattern of diurnal salinity variations is not only dependent on the strength of the forcing terms, but also on the phasing of winds and convective overturning. A comparison of mixed-layer depth computed with hourly and with daily averaged salinity reveals that diurnal salinity variability can have a significant effect on upper ocean stratification, suggesting that representing diurnal salinity variability could potentially improve air-sea interaction in climate models. Comparisons between salinity observations from moorings and from the Aquarius satellite (level 2 version 3.0 data) reveal that the typical difference between ascending-node and descending-node Aquarius salinity is an order of magnitude greater than the observed diurnal salinity anomalies at 1 m depth. Key Points Diurnal salinity throughout the tropics up to 0.01 psu Diurnal entrainment and precipitation drive diurnal salinity Aquarius ascending-descending difference exceeds day-night salinity signal

© 2014. American Geophysical Union. All Rights Reserved. Observations from 35 tropical moorings are used to characterize the diurnal cycle in salinity at 1 m depth. The amplitude of diurnal salinity anomalies is up to 0.01 psu and more typically ∼0.005 psu. Diurnal variations in precipitation and vertical entrainment appear to be the dominant drivers of diurnal salinity variability, with evaporation also contributing. Areas where these processes are strong are expected to have relatively strong salinity cycles: the eastern Atlantic and Pacific equatorial regions, the southwestern Bay of Bengal, the Amazon outflow region, and the Indo-Pacific warm pool. We hypothesize that salinity anomalies resulting from precipitation and evaporation are initially trapped very near the surface and may not be observed at the 1 m instrument depths until they are mixed downward. As a result, the pattern of diurnal salinity variations is not only dependent on the strength of the forcing terms, but also on the phasing of winds and convective overturning. A comparison of mixed-layer depth computed with hourly and with daily averaged salinity reveals that diurnal salinity variability can have a significant effect on upper ocean stratification, suggesting that representing diurnal salinity variability could potentially improve air-sea interaction in climate models. Comparisons between salinity observations from moorings and from the Aquarius satellite (level 2 version 3.0 data) reveal that the typical difference between ascending-node and descending-node Aquarius salinity is an order of magnitude greater than the observed diurnal salinity anomalies at 1 m depth. Key Points Diurnal salinity throughout the tropics up to 0.01 psu Diurnal entrainment and precipitation drive diurnal salinity Aquarius ascending-descending difference exceeds day-night salinity signal

Evaporation from the soil surface (E) can be a significant source of water loss in arid areas. In sparsely vegetated systems, E is expected to be a function of soil, climate, irrigation regime, precipitation patterns, and plant canopy development and will therefore change dynamically at both daily and seasonal time scales. The objectives of this research were to quantify E in an isolated, drip-irrigated vineyard in an arid environment and to simulate below canopy E using the HYDRUS (2-D/3-D) model. Specific focus was on variations of E both temporally and spatially across the inter-row. Continuous above canopy measurements, made in a commercial vineyard, included evapotranspiration, solar radiation, air temperature and humidity, and wind speed and direction. Short-term intensive measurements below the canopy included actual and potential E and solar radiation along transects between adjacent vine-rows. Potential and actual E below the canopy were highly variable, both diurnally and with distance from the vine-row, as a result of shading and distinct wetted areas typical to drip irrigation. While the magnitude of actual E was mostly determined by soil water content, diurnal patterns depended strongly on position relative to the vine-row due to variable shading patterns. HYDRUS (2-D/3-D) successfully simulated the magnitude, diurnal patterns, and spatial distribution of E, including expected deviations as a result of variability in soil saturated hydraulic conductivity. © 2014. American Geophysical Union.

Thymbra spicata var. spicata is known as “Zahter ”, “Sater” or “Karabaş thyme in the Southeastern Anatolia Region of Turkey and leaves and flowers are consumed as spices and tea, while young shoots are consumed as salads.This study was carried out to determine the change in essential oil content and chemical compositionduring the daytime of the Thymbra spicata plant in Ermenek district of Karaman.In order to determine the diurnal variation, the harvest was done at 5 different hours during the daytime (6:00, 9:00, 12:00, 15:00 and 18:00) in the flowering period. The harvested plants were dried in the shade and the essential oil contents were determined by Clevenger apparatus by hydro distillation and analyzed by GC-MS. The highest content of essential oil was obtained at 18.00 hours with 2.96% and the lowest one’s was obtained at 12.00 hours with 2.20%.The main components of the essential oil were determined as carvacrol (23.29% - 39.89%), thymol (16.24% - 21.52%) and γ-terpinene (18.01% - 20.90%).

Abstract An analysis of a satellite ocean surface turbulent flux product demonstrated that, as expected, the western boundary current regions dominate the seasonal cycle amplitude. Surprisingly, our analysis of the global ocean diurnal flux variability also demonstrated a regional maximum in the winter over the western boundary current regions. We conducted comparisons with in situ data from several buoys located in these regions. The buoy data were in general agreement with the relative magnitude, timing, and importance of each of the bulk parameters driving the latent and sensible heat fluxes. Further analysis demonstrated that the strength and timing of the diurnal signal is related to the location of the buoy relative to the region of maximum heat flux and sea surface temperature gradient. In both regions, the timing of the higher winds coincides with the moistest surface layer, indicating that surface fluxes rather than entrainment mixing play a key role in this phenomenon.

Long-term evidence shows an increased risk of cardiovascular events in the morning hours and recent studies in aspirin-treated patients have shown increased platelet reactivity at the end of the dosing interval. Similar pharmacodynamic analyses of adenosine-diphosphate (ADP) receptor inhibitors are scarce. We therefore investigated changes in clopidogrel-dependent platelet function and activation over 24 h and whether enhanced platelet turnover might explain diurnal variability of platelet function and activation. Twenty-one patients after acute coronary syndromes (ACS) on maintenance doses of clopidogrel (75 mg) and aspirin (100 mg) Once per day (OD) were included. Blood was collected at five time points in 24 h. Platelet function and activation was analyzed by vasodilator-stimulated phosphoprotein-phosphorylation (VASP-P), Verify Now, multiple electrode aggregometry (MEA), and platelet PAC-1 and P-selectin (P-sel) expression. Additionally, platelet count, mean platelet volume (MPV), and reticulated platelet fraction (RPF) were analyzed. There was significant diurnal variability of clopidogrel effects as documented with VASP-P, Verify Now, and PAC-1 and P-sel (all p

Objectives: This study aims to investigate the diurnal variability of heart rate (HR) increment after standing (ΔHR) in pediatric postural tachycardia syndrome (POTS) and explore appropriate cutoff values of ΔHR at different times for the POTS diagnosis.Materials and Methods: Seventy-eight patients (9–14 years) who presented with orthostatic intolerance symptoms were enrolled. Forty-three patients were diagnosed as POTS (ΔHR ≥40 bpm), and 35 patients were assigned to the non-POTS group (ΔHR

PURPOSE OF THE RESEARCH: To identify distinct latent classes of individuals based on ratings of morning and evening fatigue; evaluate for differences in phenotypic characteristics, as well as symptom and quality of life scores, among these latent classes; and evaluate for an overlap in morning and evening fatigue class membership. PATIENTS AND METHODS: In a sample of 167 oncology outpatients and 85 of their FCs, growth mixture modeling was used to identify distinct latent classes based on ratings of morning and evening fatigue obtained before, during, and after radiation therapy. Analyses of variance and Chi Square analyses were used to evaluate for differences among the morning and evening fatigue latent classes. RESULTS: Three distinct latent classes for morning fatigue were identified. Participants in the High Morning Fatigue class (47%) were younger and had lower functional status. Three distinct latent classes for evening fatigue were identified. Participants in the High Evening Fatigue class (61%) were younger, more likely to be female, more likely to have children at home, and more likely to be a FC. Only 10.3% of participants were classified in both the Very Low Morning and Low Evening Fatigue classes and 41.3% were classified in both the High Morning and High Evening Fatigue classes. CONCLUSIONS: Different characteristics were associated with morning and evening fatigue, which suggests that morning and evening fatigue may be distinct but related symptoms. Additional research is needed to elucidate the mechanisms that may underlie diurnal variability in fatigue.

Purpose of the researchTo identify distinct latent classes of individuals based on ratings of morning and evening fatigue; evaluate for differences in phenotypic characteristics, as well as symptom and quality of life scores, among these latent classes; and evaluate for an overlap in morning and evening fatigue class membership.Patients and methodsIn a sample of 167 oncology outpatients and 85 of their FCs, growth mixture modeling was used to identify distinct latent classes based on ratings of morning and evening fatigue obtained before, during, and after radiation therapy. Analyses of variance and Chi Square analyses were used to evaluate for differences among the morning and evening fatigue latent classes.ResultsThree distinct latent classes for morning fatigue were identified. Participants in the High Morning Fatigue class (47%) were younger and had lower functional status. Three distinct latent classes for evening fatigue were identified. Participants in the High Evening Fatigue class (61%) were younger, more likely to be female, more likely to have children at home, and more likely to be a FC. Only 10.3% of participants were classified in both the Very Low Morning and Low Evening Fatigue classes and 41.3% were classified in both the High Morning and High Evening Fatigue classes.ConclusionsDifferent characteristics were associated with morning and evening fatigue, which suggests that morning and evening fatigue may be distinct but related symptoms. Additional research is needed to elucidate the mechanisms that may underlie diurnal variability in fatigue.

Diurnal variability of ocean CO2 system variables is poorly constrained. Here, this variability and its drivers are assessed using 3‐h observations collected over 8–140 months at 37 stations located in diverse marine environments. Extreme diurnal variability, that is, when the daily amplitude exceeds the 99th percentile of diurnal variability, is comparable in magnitude to the seasonal amplitude and can surpass projected changes in mean states of pCO2 and [H+] over the twenty‐first century. At coastal sites and near coral reefs, extremes in diurnal amplitudes reach 187 ± 85 and 149 ± 106 μatm for pCO2, 0.21 ± 0.08 and 0.11 ± 0.07 for pH, and 1.2 ± 0.5 and 0.8 ± 0.4 for Ωarag, respectively. Extreme diurnal variability is weaker in the open ocean, but still reaches 47 ± 18 μatm for pCO2, 0.04 ± 0.01 for pH, and 0.25 ± 0.11 for Ωarag. Diurnal variability of the ocean CO2 system is considerable and likely to respond to increasing CO2. Therefore, it should be represented in Earth system models. Plain Language Summary: Our understanding of how ocean pH and related chemical variables vary during the day (known as diurnal variability) is not well established. Here, we use a recent data set of such observations collected every 3 h during 8–140 months from 37 buoys located across the oceans to assess these diurnal variations and what drives them. In extreme cases, observed changes over 24 h were found to be greater than those observed between seasons. Diurnal variations in these chemical variables are particularly large in coastal waters and near coral reefs and are not negligible further offshore. Along with the more gradual, long‐term acidification of the ocean from atmospheric CO2 increases year after year, diurnal and seasonal variability of ocean chemistry is also expected to change dramatically. Understanding how this diurnal variability will change in the future is important because it modulates the levels of acidification experienced by marine organisms from long‐term yearly changes. Key Points: Multi‐year 3‐h observations of CO2 system variables are used to assess diurnal and seasonal variability across marine environmentsAmplitudes of extreme diurnal variations in pCO2, pH, and Ωarag are often comparable to those of seasonal cyclesThe balance between different drivers of diurnal and seasonal CO2 system variability differs across timescales and environments [ABSTRACT FROM AUTHOR]

The sub-daily variability of latent (LHF) and sensible heat flux (SHF) in the Bay of Bengal (BoB) during the summer (May–September) is examined using moored buoys data at 8° N (2008 and 2011), 12° N (2010, 2011, 2012, 2013, 2014, and 2015), and 15° N (2009, 2013, 2014, and 2015) along 90° E. In the weak wind regime (< 6 ms−1), LHF loss from the ocean shows semi-diurnal variability with a higher range at 8° N (~ 21 Wm−2) than at 12° N (~ 13 Wm−2) and 15° N (~ 8 Wm−2). However, LHF depicts a diurnal variability in the strong wind regime (> 6 ms−1) with a range of ~ 13 Wm−2 at 8° N and ~ 17 Wm−2 at 12° N and 15° N. In the strong wind regime, SHF shows heat gain by the ocean with a maximum (minimum) value during the daytime (night), while it shows heat loss from the ocean in the weak wind regime with maximum (minimum) value during the night (daytime). The diurnal range of SHF does not show significant meridional variation in the strong (~ 3.5 Wm−2) and weak (~ 2 Wm−2) wind regime. The difference in sub-daily evolution of air-temperature, air-specific humidity, and wind speed determines distinct evolutions of LHF and SHF in different wind regimes, which appears to be driven by atmospheric boundary layer processes and eastward propagating land-sea breeze signals over the BoB. Finally, we also establish the relationship between sub-daily evolutions of turbulent heat fluxes in the different wind regimes with synoptic conditions associated with the active and break phases of the Indian summer monsoon. [ABSTRACT FROM AUTHOR]

This study developed a new atmospheric correction algorithm, GeoNEX-AC, that is independent from the traditional use of spectral band ratios but dedicated to exploiting information from the diurnal variability in the hypertemporal geostationary observations. The algorithm starts by evaluating smooth segments of the diurnal time series of the top-of-atmosphere (TOA) reflectance to identify clear-sky and snow-free observations. It then attempts to retrieve the Ross-Thick–Li-Sparse (RTLS) surface bi-directional reflectance distribution function (BRDF) parameters and the daily mean atmospheric optical depth (AOD) with an atmospheric radiative transfer model (RTM) to optimally simulate the observed diurnal variability in the clear-sky TOA reflectance. Once the initial RTLS parameters are retrieved after the algorithm’s burn-in period, they serve as the prior information to estimate the AOD levels for the following days and update the surface BRDF information with the new clear-sky observations. This process is iterated through the full time span of the observations, skipping only totally cloudy days or when surface snow is detected. We tested the algorithm over various Aerosol Robotic Network (AERONET) sites and the retrieved results well agree with the ground-based measurements. This study demonstrates that the high-frequency diurnal geostationary observations contain unique information that can help to address the atmospheric correction problem from new directions.

Projections of future climate are sensitive to the representation of upper-ocean diurnal variability, including the diurnal cycle of winds. Two different methods suitable for time series with missing data are used here to characterize how observed diurnal winds vary over the year. One is based on diurnal composites of mooring data, and the other is based on harmonic analysis via a least squares fit and is able to isolate annual (i.e., 1 cycle per year) modulation of diurnal variability. Results show that the diurnal amplitude in meridional winds is larger than in zonal winds and peaks in the tropical Pacific, where diurnal variability in zonal winds is overall weaker compared to other basins. Furthermore, the amplitude and phasing of diurnal winds in the tropical oceans are not uniform in time, with overall larger differences through the year in the meridional component of tropical winds. Estimating the annual modulation of the diurnal signal implies resolving both the diurnal energy peak and also the modulation of this peak by the annual cycle. This leads to a recommendation for sampling at least 6 times per day and for a duration of at least 3 years.

Isoflavones and soyasaponins are major specialized metabolites accumulated in soybean roots and secreted into the rhizosphere. Unlike the biosynthetic pathway, the transporters involved in metabolite secretion remain unknown. The developmental regulation of isoflavone and soyasaponin secretions has been recently reported, but the diurnal regulation of their biosynthesis and secretion still needs to be further studied. To address these challenges, we conducted transcriptome and metabolite analysis using hydroponically grown soybean plants at 6‐hr intervals for 48 hr in a 12‐hr‐light/12‐hr‐dark condition. Isoflavone and soyasaponin biosynthetic genes showed opposite patterns in the root tissues; that is, the former genes are highly expressed in the daytime, while the latter ones are strongly induced at nighttime. GmMYB176 encoding a transcription factor of isoflavone biosynthesis was upregulated from ZT0 (6:00 a.m.) to ZT6 (12:00 a.m.), followed by the induction of isoflavone biosynthetic genes at ZT6. The isoflavone aglycone content in the roots accordingly increased from ZT6 to ZT18 (0:00 a.m.). The isoflavone aglycone content in root exudates was kept consistent throughout the day, whereas that of glucosides increased at ZT6, which reflected the decreased expression of the gene encoding beta‐glucosidase involved in the hydrolysis of apoplast‐localized isoflavone conjugates. Co‐expression analysis revealed that those isoflavone and soyasaponin biosynthetic genes formed separate clusters, which exhibited a correlation to ABC and MATE transporter genes. In summary, the results in this study indicated the diurnal regulation of isoflavone biosynthesis in soybean roots and the putative transporter genes responsible for isoflavone and soyasaponin transport. [ABSTRACT FROM AUTHOR]

Eastern India is characterized by high aerosol loading of primarily anthropogenic origin due to both local emissions and long-range transport and hence outflow of air mass from the Indo-Gangetic Plains. Using a year-long measurement of atmospheric aerosol optical properties over Bhubaneswar, one of the fastest growing tier-two cities in the Eastern India, we show that the aerosol optical depth (AOD) varied between 0.39 and 0.96 with high loading during February and low during July. The Angstrom exponent (AE) was found to be mostly higher than unity indicating large dominance of fine mode particles with a larger AE. Further analysis using spectral curvature of AOD and satellite-based estimates indicates that more than 80% of the time, fine mode aerosols dominate the region. It is observed that there is a large diurnal variability in AOD (AE) of the order of 15% (5%) indicating a large change in loading (spectral characteristics) over a short period of within a day. The aerosols types inferred from spectral curvature method match reasonably well with those from MERRA-2 chemical reanalysis. Further, it is found that satellite-derived AOD's are low biased with respect to ground measurements and are unable to capture seasonality consistently. These findings show that additional research is required to assess the causes for such inconsistency especially during the monsoon period. [ABSTRACT FROM AUTHOR]

The objective of this study is to examine the diurnal variability of C-reactive protein (CRP) in obstructive sleep apnea (OSA).Participants included 44 women and men with untreated OSA (mean apnea/hypopnea index = 37.5, SD ± 28) and 23 healthy adults with no OSA. Sleep was monitored with polysomnography in the University of California San Diego General Clinical Research Center. Over a 24-h period, blood was collected every 2 h, and CRP levels were determined.Adjusting for age, gender, and body mass index, a significant group by time interaction showed that patients with OSA had higher CRP levels during the daytime (8:00 a.m.–8:00 p.m.) versus the nighttime (10:00 p.m. until 6:00 p.m.; p