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In order to investigate the effect of wave processes on the geotechnical characteristics of topmost sediments, a Portable Free Fall Penetrometer (PFFP) was deployed in the energetic nearshore zone of the U.S. Army Corps of Engineers' Field Research Facility (FRF) in Duck, NC. A total of 335 deployments were conducted from the FRF's 560 m long pier over six non-consecutive days in September and October of 2016. During the surveying period, significant wave heights varied between Hs = 0.8–2.4 m measured at a water depth of 17.4 m. The results showed that the sediment strength is affected by the wave climate. The derived average maximum quasi-static bearing capacities (qsbc), which reflects sediment strength, during low energy wave periods (September 22–24 and 26; Hs = 0.8–1.3 m) ranged between 67 and 73 kPa with maximum qsbc values of 120–136 kPa, while the average values were 47–59 kPa with a maximum qsbc of 82–98 kPa during the high energy wave periods (October 5–6; Hs = 2.4 m). Results also showed that the sediment strength decreased in the shallow water depth regions in spite of the increase in the particle size distribution, due to the increasing wave impact on the seabed within the shallow water region. The area where seabed strength variations were affected by the wave action became wider in the cross-shore direction as the wave height increased. Results further showed that the strength of the topmost sediment layers varied spatially along the profile and temporarily with variations in significant wave height. This likely reflects the impact of waves on sediment strength.

Accurate estimates of cumulative N 2 O fluxes from agricultural soil are essential for quantifying global N 2 O emissions and for identifying effective mitigation strategies. This study focuses on the short term temporal variability of N 2 O fluxes, and on how the accuracy of annual cumulative estimates is affected by different (simulated) measuring frequencies of an automatic system based on the closed chamber method. Fluxes were measured with high temporal resolution (24 per day) for approximately one year on agricultural soil in the southwest of Sweden. The short-term temporal variability of N 2 O fluxes was considerable: the predictive power of measured fluxes decreased to negligible levels in a time frame of 4-5 h, and large intraday flux ranges were observed frequently, particularly in days with soil temperatures below 0 ∘ C. A time of day well suited for consistently providing good estimates of the mean daily flux could not be identified. Consequently, the accuracy of annual emission estimates strongly depended on the measuring frequency. Multiple measurements per day were necessary for consistently quantifying annual emission estimates with accuracy. Accuracy improved with measuring frequency increasing up to four times per day, and higher frequencies generated negligible further improvements. Based on this study the following recommendations are made with regard to measuring frequency: i) measure four times per day for maximum accuracy and ii) measure twice per day for a good compromise between accuracy and the number of plots that can be monitored.

Halocarbons are widely used in the Greater Pearl River Delta (PRD) region of China. To study the long-term trends, source changes and emissions of major halocarbons, a total of 1505 canister air samples were collected in the Greater PRD region during 2001–2018. Mixing ratios of CFCs decreased significantly over the past 18 years except for CFC-114, which significantly increased in the Greater PRD, consistent with the recent observations of significant CFC-114 emissions in East Asia. Declines in CFCs in the Greater PRD region were faster than those at the background Mauna Loa (MLO) site, indicating effective control regulations. Source apportionment simulations showed that refrigeration applications, including refrigeration industry and CFCs replacement, were the main sources of halocarbons. During the study period, refrigeration industry experienced a progressive decline in both mixing ratio and percentage, while the contribution of CFCs replacement remained increasing. Contribution of solvent use in electronic industry traced by C2Cl4 dramatically decreased during the study period, and stayed at a low level in recent years. Based on the measured ratios of halocarbons to CO, the estimated total halocarbon emissions in 2016 were 46.5 ± 16.7 Gg for the Greater PRD region. This study provides useful information for examining the evolving emission status of halocarbons in the Greater PRD region in response to control strategies and changing usage.

Disinfection by-products (DBPs) constitute a large family of compounds. Trihalomethanes and haloacetic acids are regulated in various countries, but most DBPs are not. Monitoring DBPs can be delicate, especially for small systems, because various factors influence their formation and speciation. Short-term variations of DBPs can be important and particularly difficult for small systems to handle because they require robust treatment and operation processes. According to our knowledge, for the first time, our study covers the short-term variability of regulated and non-regulated DBP occurrence in small systems in the summer. An intensive sampling program was carried out in six small systems in Canada. Systems in the provinces of Newfoundland and Labrador and Quebec were sampled daily at the water treatment plant and at six different locations along the distribution system. Five DBP families were studied: trihalomethanes, haloacetic acids, haloacetonitriles, halonitromethanes and haloketones. Results show that there were considerable variations in DBP levels from week to week during the month of study and even from day to day within the week. On a daily basis, DBP levels can fluctuate by 22% to 96%. Likewise, the large number of sampling locations served to observe DBP variations along the distribution system. Observations revealed some degradation and decomposition of non-regulated DBPs never before studied in small systems that are associated with the difficulty these systems experience in maintaining adequate levels of residual disinfectant. Finally, this study reveals that the short term temporal variability of DBPs is also influenced by spatial location along the distribution system. In the short term, DBP levels can fluctuate by 23% at the beginning of the system, compared to 40% at the end. Thus, spatial and temporal variations of DBPs in the short term may make it difficult to select representative locations and periods for DBP monitoring purposes in small systems.

Background Takotsubo cardiomyopathy (TC) is an acute heart failure syndrome. Despite an often rapid recovery in left ventricular ejection fraction (LVEF), TC is associated with morbidity and mortality in select patients which may be due to persistent abnormalities in myocardial mechanics. Strain echocardiography quantifies myocardial deformation and is a sensitive marker of myocardial dysfunction. The aim of this study was to evaluate the short-term temporal changes in LVEF and myocardial deformation between presentation and close follow-up. Hypothesis Improvement in LVEF will occur prior to improvement in myocardial strain at short-term follow-up. Methods Patients with an ICD9/10 diagnosis code of TC were identified using the Northwestern University Enterprise Data Warehouse. All TC patients with echocardiograms at presentation and within 21 days of presentation were included. Two-dimensional speckle-tracking echocardiography (2DSTE) was performed using Tomtec Arena 2.21 software to assess LVEF, LV peak global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS), as well as RV fractional area change (FAC) and peak free wall strain (FWS). Statistical analysis was performed using a paired samples Student's t-test with a p-value Results The study cohort included 80 patients with 80% females and mean age 65.6 ± 15.4 yrs. Patients were grouped by timing of follow-up echocardiogram: within 3 days, between 4-10 days, and between 11-21 days from presentation. Compared to baseline echocardiogram, there was significant improvement in LVEF (29.0% vs 37.6%, p = 0.001) and GLS (−10.6% vs −12.7%, p = 0.022) in patients with follow up echocardiograms within 3 days ( Table 1 ). Significant improvement in GCS (−15.3% vs −21.7%, p = 0.005) and GRS (24.2% vs 32.0%, p = 0.035) was not seen until 4-10 day follow up. At 21 day follow-up, significant improvement in RV FAC (27.5% vs 34.5%, p = 0.008) and RV FWS (−13.6% vs −18.4%, p = 0.002) was noted. Conclusion In our single-center cohort of TC patients, improvement in LVEF and GLS was noted relatively early after initial presentation. The improvement in GCS and GRS occurred later, indicating persistent cardiac dysfunction despite improved but not fully recovered LVEF. Furthermore, recovery in RV dysfunction occurred after improvement in all LV parameters. These persistent abnormalities in myocardial mechanics provide further insight into myocardial recovery in TC and the potential for improvements in risk stratification and management of these patients.

This paper focused on the temporal and spatial variability of sulphur dioxide (SO2) from 2004 to 2013 over 36 ground-based (GB) stations located in Gauteng and Mpumalanga provinces of South Africa. The assessment was based on the in situ SO2 data, where the GB stations were sorted into different groups and in addition, kriging-based analysis and OMI SO2 data (2004–2013) were deployed to study their seasonal spatial variability. It was observed that Pretoria west, Witbank and Randwater had high SO2 levels and standard deviations. Although, winter played a major role in having peak SO2 values in most of the stations, it was surpassing that in spring the SO2 levels of Witbank and Pretoria west stations dropped and Randwater had the highest standard deviation of 11.2 ppbv in October. A prominent seasonal variation was seen in all the groups, excluding Mpumalanga power stations (MP) group. This was particularly evident in the Vaal Triangle group. Highveld group ranked topmost level with elevated SO2 values proceeded by the MP group in all the temporal time scales. The spatial based analysis further proved that the highest SO2 levels were centred around major industrial regions of Mpumalanga, regardless of all the seasons.

Images of wide-angle visible standard CCD cameras contain information on in-vessel dusts such as dust creation events (DCEs) that occur during plasma operations, and their velocity. Analyzing the straight line-like dust traces in the shallow cylindrical shell-structured scrape-off layer along the vacuum vessel, a database on the short/long term temporal evolutions, spatial locations of DCEs caused by plasma–dust interaction, and the dust velocity distribution are built. We have studied DCEs of 2010 and 2011 KSTAR campaign.

Dissolved organic carbon (DOC) plays an important role in both terrestrial and aquatic ecosystems. In-stream DOC concentration is an important indicator of water quality, because high in-stream DOC concentrations naturally lead to reductions in dissolved oxygen. Recent studies indicate that DOC is responsible in transferring toxic metals (e.g., mercury, Hg) from terrestrial sources to aquatic ecosystems. However, assessing DOC or Hg dynamics is fairly challenging as a result of extreme spatiotemporal variation. Typically, process-based models with short-to-medium term temporal resolutions are required to model DOC and Hg dynamics. The objective of this research is to develop a watershed-based monthly DOC production and export model that integrates the treatment of (i) forest-litter decomposition (DOC production), (ii) wetland-to-watershed area ratio (DOC storage), and (iii) relevant hydrological processes (DOC export) in the simulation of in-stream concentrations. Model results are compared against DOC concentrations collected at the stream outlets of two separate forested watersheds in Kejimkujik National Park, Atlantic Canada. Comparisons for the two watersheds show that predicted monthly DOC concentrations are generally in good agreement with field-based concentrations, giving R2-values of 0.61 and 0.63 for Pine Marten Brook watershed and 0.72 and 0.75 for Moose Pit Brook watershed for model calibration and validation, respectively.

Reported herein are the results of eight soil CO2 efflux surveys performed from 2006 to 2011 at Timanfaya Volcanic Field (TVF), Lanzarote Island with the aim of evaluating the long- and short-term temporal variations of the diffuse CO2 emission. Soil CO2 efflux values ranged from non-detectable up to 34.2 g m−2 d−1, with the highest values measured in September 2008. Conditional sequential Gaussian simulations (sGs) were applied to construct soil CO2 efflux distribution maps and to estimate the total CO2 output from the studied area at the TVF. Soil CO2 efflux maps showed a high spatial and temporal variability. Total CO2 emission rates ranged between 41 and 518 t d−1, February 2011 (winter) being the season when maximum diffuse CO2 emission rates were observed. To investigate the influence of external variables on the soil CO2 efflux, a geochemical station (LZT01) was installed at TVF to measure continuously the soil CO2 efflux between July 2010 and March 2012 Since external factors such as barometric pressure, rainfall, soil water content, soil and air temperatures, and wind speed influence strongly the observed soil CO2 effluxes, multiple regression analysis was applied to the time series recorded by the automatic geochemical station LZT01 to remove the contribution of these external factors. The influence of meteorological variables on soil CO2 efflux oscillations accounts for 13% of total variance, with barometric pressure, rainfall and/or soil water content having the most influence in the control of the soil CO2 efflux. These observations along with the results from the eight soil gas surveys performed at TVF indicate that the short and long-term trends in the diffuse CO2 degassing are mainly controlled by environmental factors.

In this paper we examine the long-term temporal characteristics of palaeomonsoon dynamics in equatorial Africa from a continuous lacustrine sequence retrieved from Sacred Lake, Mount Kenya (0°03′N, 37°32′E, 2350 m a.s.l.), covering the last interglacial–glacial transition to the present. The trends in mineral magnetics and stable carbon isotopes are proxy indicators of changes in precipitation on the mountain over the last glacial–interglacial cycle. Spectral analysis by a fast fourier transform method revealed that the stable carbon isotope trend (δ 13 C) has strong signals at the 23,000 and 11,500 year frequencies. The mineral magnetic signature does not register the 23,000 year cycle observed in the δ 13 C signature. It has, however, a strong signal at an 11,500 year frequency, and sharp but relatively weak peaks at ca. 7500 and 5000 year frequencies are recorded. The dominant 23,000 year frequency recorded in the δ 13 C signature reflects the strong effect of the precessional cycle on tropical climate and ecosystems, and is most probably effected via global atmospheric pCO 2 and temperature changes. The shorter cycles at 11,500 year (indicated by both mineral magnetics and δ 13 C trends), and 7500 and 5000 years BP (apparent in the mineral magnetic record) are attributed to precipitation variations, whose temporal cycles are dominated by the higher precessional harmonics.

The results of measurements of absolute flux values and long term temporal evolution of the spatial distribution of trapped He ions in the energy range 1.2 – 9.2 MeV/nucleon below L = 4 are reported. The observations were made with ion counter on board the Japanese OHZORA satellite during the period of January 1984 through March 1987.

The decay time of stereoscopic depth sensation after the occlusion of one eye is measured for well suprathreshold disparities and for binocular inspection times ranging from 5 to 30 sec. In a dark environment, devoid of any cue, the decay time may attain even 10 sec.This long-term effect is tentatively ascribed to a possible facilitatory interaction between information gained through spontaneous fluctuation of accommodation and that due to binocular disparity. Last, the suggestion is made that the decay time might represent an estimate of stereoscopic depth sensation.

A brief clinical and pathologic summary of the syndrome of temporal arteritis is made, with a report of three new cases, one of which was fatal and in which an autopsy was performed. This condition, first reported in 1932 by Horton, Magath and Brown, is characterized by severe headaches, pain in the temporal region and the presence of inflamed, thickened and tortuous temporal arteries. Constitutional symptoms of a generalized infection are also present. The characteristic pathologic lesion consists of proliferation of inflamed fibrous tissue of all layers of the affected vessel, together with focal necrosis and granulomatous lesions associated with foreign body giant cell formation in the media. Good therapeutic results are obtained by procaine injection, surgical excision of a portion of the diseased vessel and, in at least one instance, antihistaminic therapy. The disorder is usually self-limited and non-fatal. Although generally a localized vascular disease of the temporal arteries, other cranial arteries, as well as arteries in other parts of the body, may show the same type of lesion. We believe the term temporal arteritis should be restricted to instances in which the affected vessel has undergone the characteristic granulomatous change associated with foreign body giant cells. We also suggest changing the regional designation temporal arteritis to that of a pathologic entity, such as non-specific granulomatous arteritis or, more simply, granulomatous arteritis.