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Long-range atmospheric transport (LRAT) plays a crucial role in the occurrence of persistent organic pollutants (POPs) in remote regions. When studying the LRAT of POPs on the Tibetan Plateau, westerly-controlled regions have received insufficient attention compared with regions influenced by the Indian monsoon or air flow from East Asia. We investigated the residual levels of POPs in soils from the eastern Pamirs and used air backward trajectory analysis to elucidate the influence of potential source regions via LRAT. Organochlorine pesticides (OCPs, mainly comprising DDTs, HCHs, and HCB), polychlorinated biphenyls (PCBs, mainly comprising penta- and hexa-CBs), and polycyclic aromatic hydrocarbons (PAHs, mainly comprising three- and four-ring) were detected at low concentrations of 40-1000,MDL-88, and 2100-34,000 pg/g, respectively. We elucidated three major geographical distribution patterns of POPs, which were influenced by (1) the distribution of total organic carbon and black carbon in soil, (2) historical use of pesticides in the Tarim Basin, and (3) continuous emissions. Central Asia and the Tarim Basin were major potential source regions of POPs reaching the eastern Pamirs via LRAT. Historical use of technical HCH or lindane and technical DDT in potential source regions may contribute to the accumulation of HCHs and DDTs in the eastern Pamirs, respectively. Local sources seem to play a more important role in the occurrence of PAHs in the study area. By being under the control of less contaminated westerly air flow, the eastern Pamirs are more pristine than the core of the Tibetan Plateau where the Indian and East Asia monsoons deliver contaminants from highly industrialized areas in East China and India.

The study was conducted in the landscapes of south-eastern Ukraine during the nesting seasons 1988–2018. Within the landscape system associated with the Molochny Estuary, the ten most important ecosystem types were investigated, including the following: agricultural land, vegetated strips, meadows, islands and spits, reedbeds, urban areas, salt marshes, steppe, cliffs, artificial forests. Bird species responded to temperature and precipitation gradients. The patterns of responses were presented using Huisman, Olff and Fresco expanded by the Jansen-Oksanen hierarchical models. The nature of species response in the gradient of temperature or precipitation conditions depends on the type of particular ecosystem and is not uniform for all populations inhabiting the different landscape types. The bird communities were revealed to demonstrate an abrupt dynamic over time. The continuous changes in community structure initiated by the external environmental factors are combined with modifications of internal biotic interactions, which may lead to abrupt reorganization of the community.

Despite frequent observations of high particulate matter (PM) concentrations in Seoul, Korea, the sulfate (SO42−) concentrations in PM with an aerodynamic diameter below or equal to 2.5 μm (PM2.5) in Seoul have been reduced during the 1990s. However, there has been no decreasing trend during the 2000s. Despite the very low ambient SO2 concentrations, high SO42− concentration episodes frequently occur in Seoul; however, the reasons for this remain poorly understood. In the present study, we sought to determine the major factors that enhance sulfur oxidation in Seoul by analyzing measurement data from an intensive air quality monitoring station in the Seoul metropolitan area acquired in 2015. Additionally, we aimed to distinguish the contributions of local sources and long-range transport to the elevated SO42− concentrations in PM2.5 in Seoul. In some cases in March and October 2015, the molar ratio of SO42− to SO2, which reflects sulfur partitioning between the particle and gas phases, showed an exponential increase with an increase of relative humidity (RH). However, despite the fact that the RH was high during August 2015, no statistically significant relationship was observed between RH and the molar ratio of SO42− to SO2 during this month. In August 2015, the molar ratio of SO42− to SO2 showed an exponential increase with increasing O3 concentration. Therefore, under sufficient RH, the concentrations of radical oxidants might be the most important factor that underlies the increase in ambient SO42− concentrations. No significant relationship was observed between the molar ratio of SO42− to SO2 and O3 in October. Furthermore, using Potential Source Density Function (PSDF) and backward trajectory analysis, the high SO42− concentrations in March 2015 were found to be caused by the transportation of air pollutants from China and local sources around Seoul. The high SO42− concentrations in August 2015 are concluded to have been greatly affected by these power plant emissions in the Taean area on the west coast of Korea. The high SO42− concentrations in October 2015 appear to have been caused by the transportation of air pollutants from North Korea. In summary, the high SO42− concentration in Seoul is affected by long-range transport from China and by the emissions from around the Seoul metropolitan area, such as Taean or North Korea.

An Attitude control system for a satellite in low earth orbit is designed in this project. As a reference, CARTOSAT-2 is selected to design the AOCS. CARTOSAT-2 is located in LEO so it suits the needs of the projects. It is mainly used for mapping of urban, rural areas and wetlands in India. To design a basic AOCS, a DC motor based model is considered. Transfer functions of DC motor and satellite dynamics model are calculated using Laplace transformation. Stability of the system is checked by plotting poles and zeroes of the systems. PID controller is used to improve the overall stability of the system by decreasing the errors in the output of the system. The systems are subjected to sine and step inputs and responses are plotted in the form of graphs. The plots are studied using SciLab as the tool to design the block diagram and the control system for the AOCS. Scilab along with FlightGear is used to visualize the response of the system.

Organophosphate esters (OPEs) are contaminants of emerging concern, and studies have concluded that urban areas are a significant source of OPEs. Samples were collected from six ground-based sites located in Chengdu, a typical rapidly developing metropolitan area in Southwest China, and were analyzed for seven OPEs in atmospheric PM 2.5 ( Σ7 OPEs). The concentrations of Σ7 OPEs in PM 2.5 ranged from 5.83 to 6.91 ng m −3 , with a mean of 6.6 ± 3.3 ng m −3 , and the primary pollutants were tris-(2-butoxyethyl) phosphate (TBEP), tri-n-butyl phosphate (TnBP), tris-(2-chloroethyl) phosphate (TCEP) and tris-(2-chloroisopropyl) phosphate (TCPP), which together made up more than 80 % of the Σ7 OPEs. The concentrations of Σ7 OPEs were higher in autumn and winter than in summer. Nonparametric tests showed that there was no significant difference in Σ7 OPE concentrations among the six sampling sites, but the occurrence of unexpectedly high levels of individual OPEs at different sites in autumn might indicate noteworthy emissions. A very strong correlation ( R2 = 0.98, p 0.01) between the OPEs in soil and in PM 2.5 was observed. Backward trajectory analysis indicated that the OPEs in PM 2.5 were mainly affected by local sources. Principal component analysis (PCA) revealed that the OPEs in PM 2.5 were largely sourced from the plastics industry, interior decoration and traffic emission (34.5 %) and the chemical, mechanical and electrical industries (27.8 %), while the positive matrix factorization (PMF) model revealed that the main sources were the plastics industry and indoor source emissions, the food and cosmetics industry and industrial emissions. In contrast to coastal cities, sustained and stable high local emissions in the studied inland city were identified, which is particularly noteworthy. Chlorinated phosphates, especially TCPP and TCEP, had a high content, and their usage and source emissions should be controlled.

In this paper, we focus on trajectories at intersections regulated by various regulation types such as traffic lights, priority/yield signs, and right-of-way rules. We test some methods to detect and recognize movement patterns from GPS trajectories, in terms of their geometrical and spatio-temporal components. In particular, we first find out the main paths that vehicles follow at such locations. We then investigate the way that vehicles follow these geometric paths (how do they move along them). For these scopes, machine learning methods are used and the performance of some known methods for trajectory similarity measurement (DTW, Hausdorff, and Fréchet distance) and clustering (Affinity propagation and Agglomerative clustering) are compared based on clustering accuracy. Afterward, the movement behavior observed at six different intersections is analyzed by identifying certain movement patterns in the speed- and time-profiles of trajectories. We show that depending on the regulation type, different movement patterns are observed at intersections. This finding can be useful for intersection categorization according to traffic regulations. The practicality of automatically identifying traffic rules from GPS tracks is the enrichment of modern maps with additional navigation-related information (traffic signs, traffic lights, etc.).

An analysis of the combustion process along gradient trajectories is presented for a set of Direct Numerical Simulations of turbulent premixed jet flames at different Reynolds numbers and approxima...

We present the observations of stratospheric aerosol at Rosgidromet lidar stations after the explosive eruption of the Raikoke volcano (Kuril Islands, 48.29° N, 153.25° E) in June 2019. The forward trajectory analysis and observations by the CALIOP lidar onboard the CALIPSO satellite were used to track how the aerosol trace in the stratosphere propagated from the volcano around the pole toward Western Siberia within a month after the eruption. We presented the lidar measurements of volcanic aerosol from late July 2019 at the Rosgidromet lidar stations in Obninsk, Znamensk, Novosibirsk, and Petropavlovsk-Kamchatsky. Volcanic aerosol was observed in the layer from 13 to 18 km. The integrated backscattering coefficient in the layer varied from a maximum of (0.8–1.6) × 10−3 sr−1 in August–September 2019 to (0.2–0.3) × 10−3 sr−1 toward the end of the year.

A four-stage collector system is developed for the experimental gyrotron at the Peter the Great St. Petersburg Polytechnic University based on spatial separation of electrons with different energies in crossed electric and magnetic fields. The conditions of use of this system for the efficient recuperation of electron residual energy in a spent beam are determined. The numerical simulation of the recuperator and the analysis of the electric and magnetic field distribution in the gyrotron collector region are accomplished. Theoretical estimations and trajectory analysis of the helical electron beam show that the system developed provides the electron residual energy recuperation necessary to achieve total gyrotron efficiency over 70%.

Trajectory analysis has been extensively applied to simulate the penetration and loading processes of electret filters. However, there is no available literature related to trajectory analysis simu...

Size-resolved trace metal concentrations at two background sites were assessed during a 1-year observation campaign, with the measurements performed in parallel at two mountain sites, where Mt. Dinghu (DHS) located in the rural region of Pearl River Delta (PRD) and Mt. Gongga (GGS) located in the Tibetan Plateau region. In total, 15 selected trace elements (Mg, Al, K, V, Mn, Fe, Cu, Zn, As, Mo, Ag, Cd, Ba, Tl, and Pb) in aerosol samples were determined using inductively coupled plasma mass spectrometry (ICPMS). The major metals in these two mountain sites were Fe, K, Mg, and Ca with concentrations ranging between 241 and 1452 ng/m3, 428 and 1351 ng/m3, 334 and 875 ng/m3, and 376 and 870 ng/m3, respectively, while the trace metals with the lowest concentrations were Mo, Ag, Cd, and Tl with concentrations lower than 4 ng/m3 in DHS and 2 ng/m3 in GGS. The pronounced seasonal variability in the trace elements was observed in DHS, with lower concentrations in spring and summer and relatively high in winter and autumn, whereas seasonal variance of trace elements is hardly observed in Mt. Gongga. The size distribution pattern of crustal elements of Al, Mg, K, Ba, and Fe was quite similar in DHS and GGS, which were mainly found in coarse particles peaked at 4.7–5.8 μm. In addition, V, Mo, Ag, and Tl were also concentrated in coarse particles, although the high enrichment factor (EF > 100) of which suggested anthropogenic origin, whereas trace metals of Cd, Mn, Zn, As, Cu, and Pb concentrated in fine mode particles. Specifically, these trace metals peak at approximately 1.5 μm in DHS, while those in GGS peaked at diameter smaller than 0.3 μm, indicating the responsible for long-range transport from the far urban and industrialized areas. Multivariate receptor model combined with the enrichment factor results demonstrated that the trace elemental components at these two background sites were largely contributed from the fossil fuel combustion (55.4% in DHS and 44.0% in GGS) and industrial emissions factors (20.1% vs. 26.5%), which are associated with long distance transport from the coastal area of Southeast China and the Northwestern India, respectively, as suggested by the backward air mass trajectory analysis. Local sources from soil dust contributed a minor variance for trace elements in DHS (9.7%) and GGS (13.8%), respectively.

The chemical composition of particulate matter impacts both human health and climate. In this study, the chemical characteristics of particulate matter was measured for four months (November 2016–February 2017) at Varanasi, which is located in the middle of the Indo-Gangetic Basin (IGB). The daily observed mean values of PM10 and PM2.5 are 134 ± 48 and 213 ± 80 μg/m3, respectively, which exceeds both national and international standards. The average value of PM2.5/PM10 ratio is 0.64 ± 0.16 which indicates a relatively higher fraction of fine particles that are attributed to anthropogenic emission sources (biomass/post-harvest burning) as corroborated by MODIS fire counts and back trajectory analysis. Ion chromatographic measurements showed that SO42−, Cl−, K+, NO3−, Na+, Ca2+, Mg2+ are the major ionic species present in the aerosol. Scanning Electron Microscopy with Energy Dispersive X-Ray (SEM–EDX) analysis shows the prevalence of carbon-rich particles at Varanasi which is likely due to biomass burning and other anthropogenic sources.

Observations of carbonaceous species [organic carbon (OC), elemental carbon (EC), water soluble organic carbon (WSOC), carbonaceous aerosols (CAs) and secondary organic carbon (SOC) ] and trace elements (As, Cr, Ni, Zn, Na, Mg, Al, P, K, Ca, Ti, Fe, and Mn) in PM10 are made over a high altitude site (ARIES, Nainital, 29.4° N, 79.5° E, ~1958 m amsl) in the central Himalayan region during October 2018−February 2019 to explore their possible sources. The average concentrations of PM10, OC, EC, WSOC, CA and SOC were recorded as 44±13 µg m-3, 3.66±1.26 µg m-3, 1.29±0.61 µg m-3, 2.28±0.76 µg m-3, 7.15±1.96 µg m-3 and 1.45±0.73 µg m-3, respectively during the study period. The concentrations of PM10, OC, EC, WSOC, CAs and SOC were significantly varied during autumn (October-November) and winter (December-February) seasons. During both the seasons, significant positive linear trend between OC & EC and OC & WSOC have been observed which is indicative of their common sources of carbonaceous aerosols at the study site. WSOC/OC ratio was estimated as 0.56 and 0.67 during autumn and winter, respectively suggested that the biomass burning could be one of the major sources of carbonaceous aerosols at Nainital. The significant positive correlation of PM10 with crustal elements (Al, Fe, Ca, Mg and Ti) as well as correlation of Al with other crustal elements (Fe, Ca, Mg and Ti) indicates the abundance of mineral dust at the sampling site. The observed Fe/Al ratio (1.07) also indicates mineral dust as a source at the sampling site, similarly, Ca/Al ratio (1.36) indicates that aerosols over this region is rich in Ca mineral as compared to average continental crust. Principal component analysis (PCA) identified the contribution of crustal/soil dust, biomass burning and industrial emissions to the PM10 over the central Himalayan region of India. Five days back trajectory analysis indicates that the air mass impacting the sampling site is from local surrounding area in Uttrakhand as well from Himachal Pradesh, Jammu & Kashmir, Ingo Gangetic Plain (IGP) region, Pakistan, Afghanistan region and Thar Desert.

Vessel monitoring system (VMS) is an effective tool for the quantified study of fishing. As the fishing vessels equipped with VMS clients, a large amount of trajectory data has been collected, which brings a new opportunity for fishing research. According to fishery safety production regulations, fishing vessels should perform grouping operations based on actual conditions, but the group information cannot be collected by the VMS. In this paper, we propose the Fishing Vessels Relationships Discovery system (FVRD) by calculating the interaction time among fishing vessels and then using it as a weight to generate a relationship network. The experiment of the proposed FVRD on the vessel dataset of Zhejiang Province reveals that the generated fishing community is consistent with the type of operation of the fishing vessels, which means the proposed method is effective. The experiment also indicates that the fishing vessel relationship network has the characteristics of small-world and scale-free that is similar to the human social network, Moreover, FVRD shows that 86.78% of vessels share the collaboration relationships over one week, 10.72% of vessels are in the long-term cooperation, confirming the regulation that most fishing vessels are sailing together for fishing.

A hotspot is an axis-aligned square of fixed side length s, where the amount of time a moving entity spends within it is maximised. An exact hotspot of a polygonal trajectory with n edges can be found with time complexity O(n 2). We define a c-approximate hotspot as an axis-aligned square of side length cs, in which the presence duration of the entity is no less than that of an exact hotspot. In this paper we present an algorithm to find a (1 + ϵ)-approximate hotspot of a polygonal trajectory with time complexity O ( n ϕ ϵ log n ϕ ϵ ) O\left( {{{n\phi } \over \varepsilon }\log {{n\phi } \over \varepsilon }} \right) , where ϕ is the ratio of average trajectory edge length to s.

Social vulnerability has been an important concept to characterize the extent to which human society is vulnerable to hazards. Although it is well known that social vulnerability varies across space and over time, there is only a paucity of studies to examine the basic patterns of the spatial and temporal dynamics of the social vulnerability in the United States. This study examines the spatial and temporal dynamics of social vulnerability of the U.S. counties from 1970 to 2010. For each decade, social vulnerability of counties is quantified by the social vulnerability index (SoVI) using county-level social, economic, demographic, and built environment characteristics. The SoVI is mainly designed to quantify the cross-sectional variation of social vulnerability and is not conducive to direct comparison over time. This study implements a methodology that integrates quantile standardization, sequence alignment analysis, and cluster analysis to investigate how social vulnerability of U.S. counties has changed over time. The authors find that U.S. counties exhibit distinctive spatial and longitudinal patterns, and there are counties/areas which have persistent high or low social vulnerability as well as frequent change in their social vulnerability over time. The results can be useful for policymakers, disaster managers, planning officials, and social scientists in general.

Power generation is associated with toxic emissions. Hydrogen sulfide (H2S) and ammonia (NH3) are toxic gases emitted from geothermal power generation that have negative impacts on health and the environment. Oxidation of H2S leads to formation of SO2 that also has health and environmental effects. The Cerro Prieto geothermal power plant (CP-GPP) is one of the largest in the world and is located 30 km south of Mexicali, a border city between Mexico and the US. Power from this plant is sold to both countries. In order to assess the potential effects of the emissions from the GPP on nearby low-income communities, H2S, SO2 and NH3 concentrations were measured at Nuevo Leon, El Chimi, and Estacion Delta, using passive samplers from November 2013 to June 2014. The highest concentrations of H2S were recorded during periods of high atmospheric stability, and exceeded the limit recommended by the WHO (150 μg m−3, 24-h) three times downwind from the GPP. Similarly, the mean SO2 concentrations at all three sites exceeded the limit established by the NOM-022-SSA1-2010 (288 μg m−3, 24-h), while NH3 concentrations exceeded the limits established by the OEHHA (100 μg m−3, 24-h) eight times at Nuevo Leon. A backward trajectory analysis indicated transport of air masses from the GPP to El Chimi and Estacion Delta sampling sites. The results indicate that GPP's emissions could affect the residents in the surrounding areas, warranting public health action to investigate exposures and risks.

Single-cell RNA-sequencing has greatly increased the spatiotemporal resolution of root transcriptomics data, but we are still only scratching the surface of its full potential. Despite the challenges that remain in the field, the orderly aligned structure of the Arabidopsis root meristem makes it specifically suitable for lineage tracing and trajectory analysis. These methods will become even more potent by increasing resolution and specificity using tissue-specific single-cell RNA-sequencing and spatial transcriptomics. Feeding multiple single-cell omics data sets into single-cell gene regulatory networks will accelerate the discovery of regulators of root development in multiple species. By providing transcriptome atlases for virtually any species, single-cell technologies could tempt many root developmental biologists to move beyond the comfort of the well-known Arabidopsis root meristem.

One of the challenging problems in robot navigation is efficient and safe planning in a highly dynamic environment, where the robot is required to understand pedestrian patterns in the environment, such as train station. The rapid movement of pedestrians makes the robot more difficult to solve the collision problem. In this paper, we propose a navigation probability map to solve the pedestrians&rsquo, rapid movement problem based on the influencer recognition model (IRM). The influencer recognition model (IRM) is a data-driven model to infer a distribution over possible causes of pedestrian&rsquo, s turning. With this model, we can obtain a navigation probability map by analyzing the changes in the effective pedestrian trajectory. Finally, we combined navigation probability map and artificial potential field (APF) method to propose a robot navigation method and verified it on our data-set, which is an unobstructed, overlooked pedestrians&rsquo, data-set collected by us.

The salamander vertebral column is largely undifferentiated with a series of more or less uniform rib-bearing presacral vertebrae traditionally designated as the trunk region. We explored regionalization of the salamander trunk in seven species and two subspecies of the salamander genus Lissotriton by the combination of microcomputed tomography scanning and geometric morphometrics. The detailed information on trunk vertebral shape was subjected to a multidimensional cluster analysis and a phenotypic trajectory analysis. With these complementary approaches, we observed a clear morphological regionalization. Clustering analysis showed that the anterior trunk vertebrae (T1 and T2) have distinct morphologies that are shared by all taxa, whereas the subsequent, more posterior vertebrae show significant disparity between species. The phenotypic trajectory analysis revealed that all taxa share a common pattern and amount of shape change along the trunk region. Altogether, our results support the hypothesis of a conserved anterior-posterior developmental patterning which can be associated with different functional demands, reflecting (sub)species' and, possibly, regional ecological divergences within species.

Biomass burning episodes measured at 14 stations of the European Aerosol Research Lidar Network (EARLINET) over 2008–2017 were analysed using the methodology described in "Biomass burning events measured by lidars in EARLINET – Part 1: Data analysis methodology" (Adam et al., 2020, this issue). The smoke layers were identified in lidar optical properties profiles. A number of 795 layers for which we measured at least one intensive parameter was analysed. These layers were geographically distributed as follows: 399 layers observed in South-East Europe, 119 layers observed in South-West Europe, 243 layers observed in North-East Europe, and 34 layers observed in Central Europe. The mean layer intensive parameters are discussed following two research directions: (I) the long-range transport of smoke particles from North America, and (II) the smoke properties (fresh versus aged), separating the smoke events into four continental source regions (European, North American, African, Asian or a mixture of two), based on back trajectory analysis. The smoke detected in Central Europe (Cabauw, Leipzig, and Hohenpeißenberg) was mostly transported from North America (87 % of fires). In North-East Europe (Belsk, Minsk, Warsaw) smoke advected mostly from Eastern Europe (Ukraine and Russia), but there was a significant contribution (31 %) from North America. In South-West Europe (Barcelona, Evora, Granada) smoke originated mainly from the Iberian Peninsula and North Africa (while 9 % were originating in North America). In the South-East Europe (Athens, Bucharest, Potenza, Sofia, Thessaloniki) the origin of the smoke was mostly local (only 3 % represented North America smoke). The following features, correlated with the increased smoke travel time (corresponding to aging) were found: the colour ratio of the lidar ratio (i.e., the ratio of the lidar ratio at 532 nm to the lidar ratio at 355 nm) and the colour ratio of the backscatter Ångström exponent (i.e., the ratio of the backscatter-related Angstrom exponent for the pair 532 nm – 1064 nm to the one for the pair 355 nm – 532 nm) increase, while the extinction Ångström exponent and the colour ratio of the particle depolarization ratio (i.e., the ratio of the particle linear depolarization ratio at 532 nm to the particle depolarization ratio at 355 nm) decrease. The smoke originating from all continental regions can be characterized on average as aged smoke, with a very few exceptions. In general, the long range transported smoke shows higher lidar ratio and lower depolarization ratio compared to the local smoke.

Data prediction and imputation are important parts of marine animal movement trajectory analysis as they can help researchers understand animal movement patterns and address missing data issues. Compared with traditional methods, deep learning methods can usually provide enhanced pattern extraction capabilities, but their applications in marine data analysis are still limited. In this research, we propose a composite deep learning model to improve the accuracy of marine animal trajectory prediction and imputation. The model extracts patterns from the trajectories with an encoder network and reconstructs the trajectories using these patterns with a decoder network. We use attention mechanisms to highlight certain extracted patterns as well for the decoder. We also feed these patterns into a second decoder for prediction and imputation. Therefore, our approach is a coupling of unsupervised learning with the encoder and the first decoder and supervised learning with the encoder and the second decoder. Experimental results demonstrate that our approach can reduce errors by at least 10% on average comparing with other methods.

Protein–ligand interaction analysis is important for drug discovery and rational protein design. The existing online tools adopt only a single conformation of the complex structure for calculating and displaying the interactions, whereas both protein residues and ligand molecules are flexible to some extent. The interactions evolved with time in the trajectories are of greater interest. MolADI is a user-friendly online tool which analyzes the protein–ligand interactions in detail for either a single structure or a trajectory. Interactions can be viewed easily with both 2D graphs and 3D representations. MolADI is available as a web application.

International audience; Growth Hormone (GH) under its human recombinant homologue (rhGH), may be abused by athletes to take advantage of its well-known anabolic and lipolytic properties; hence it is prohibited in sports by the World Anti-Doping Agency. Due to the rapid turnover of rhGH, anti-doping screening tests have turned to monitor two endocrine biomarkers (IGF-I and P-III-NP), but unfortunately, they show population-wise variability, limiting the identification rate of rhGH users. Previous studies have evidenced the numerous effects of GH on human physiology, especially in hematopoiesis and steroidogenesis. In this work, aiming to discover novel physiological rhGH biomarkers, we analyzed the complete blood count and the steroidomics profile of healthy, physically active, young males treated either with EPO + rhGH or EPO + placebo. The time-trends of these two physiological routes have been analyzed through geometric trajectory analysis (GTA) and OPLS-DA. Individuals supplemented with micro-doses of rhGH exhibited different leukopoietic and steroidal profiles compared to the control population, suggesting a role of the rhGH in both pathways. In the article, hypotheses on the observed differences are discussed according to the most recent literature and compared to results in animal models. The use of leukopoietic and steroidal biomarkers together with endocrine biomarkers (IGF-1 and P-III-NP) allows to correctly classify over 98% of samples with no false positives, miss-classifying only one single sample (false negative) over a total of 56; a promising result, if compared to the current rhGH detection strategies.

Given the trajectories of one or several moving groups, we propose a new framework, the group diagram (GD) for representing these. Specifically, we seek a minimal GD as a concise representation of the groups maintaining the spatio-temporal structure of the groups’ movement. A GD is specified by three input values, namely a distance threshold, a similarity measure and a minimality criterion. For several variants of the GD, we give a comprehensive analysis of their computational complexity and present efficient approximation algorithms for their computation. Furthermore, we experimentally evaluate our algorithms on GPS data of migrating geese. Applying the proposed methods on these data sets reveals how the GD concisely represents the movement of the groups. This representation can be used for further analysis and for the formulation of new hypotheses for further ecological research, such as differences in movement patterns of groups on different surfaces or the shift of migration routes over several years. We use different similarity measures to summarize the migration routes of (i) a goose family for one migration period and to summarize (ii) the migration routes of one individual for several migration periods or (iii) the migration routes of several independent individuals for one migration period. published

New data on the black carbon (BC) content in the atmosphere are obtained during year-round daily monitoring of BC concentration in the near-surface air layer in a hard-to-reach region of the northern Urals (on the territory of Pechora-Ilych Nature Reserve) with the time resolution of 1 day. Results are analyzed for the cold half-year (from October 2017 to March 2018), when only BC of anthropogenic origin is present in the atmosphere and no fire effect is possible. Average BC concentrations (plus or minus standard deviation) are (296 ± 172) and (175 ± 82) ng/m3 in the near-surface air of Yaksha settlement and outside it, respectively. Comparison of monthly average BC concentrations in the near-surface air with those estimated from satellite observations ( https://giovanni.gsfc.nasa.gov/giovanni/ ) shows a satisfactory agreement, serving as a cross-check and confirming the reliability of results. Trajectory analysis of long-range transport of air masses and BC for the region of Pechora-Ilych nature reserve made it possible to identify the main anthropogenic BC sources in the atmosphere at distances less than 500 km on industrial territories of the central Urals, areas of carbon-containing fuel production in Yamalo-Nenets and Khanty-Mansiysk Autonomous Districts, in the cities and settlements of Perm oblast, Udmurtia, and the Komi Republic.

Continuous online measurements of fine particulate matter mass (PM2.5) and its chemical composition were carried out at an urban monitoring site in Wuhan from March 2017 to February 2018. The PM2.5 mass concentration ranged from 6.3 to 223 μg/m3, with the highest in winter and the lowest in summer. Water soluble ions (WSIs) were the most abundant component in PM2.5 (28.8 ± 22.9 μg/m3), followed by carbonaceous aerosol (11.9 ± 10.4 μg/m3) and elements (5.5 ± 6.7 μg/m3). It is noteworthy that six episodes of sustained high PM were observed during the study period. Five major contributors of PM2.5 were identified by positive matrix factorization (PMF) to be the iron and steel industry, fugitive dust, secondary photochemistry, traffic-related emission and biomass burning, contributing 26.3%, 5.5%, 29.5%, 29.2% and 9.6% to PM2.5, respectively. Furthermore, conditional probability function (CPF), trajectory analysis and potential source contribution function (PSCF) were used to identify the influences of local activities and regional source. Local sources mainly include Wuhan iron and steel group, construction sites and urban trunk roads, etc. Three pollution transport pathways of PM2.5 in Wuhan were identified to be northwest, east and south pathway, with the relative contribution of 40%, 17% and 43%, respectively. Western Henan, northern Shaanxi and southwestern Shanxi were identified to be the major potential source regions of PM2.5 in Wuhan.

We have measured black carbon (BC) concentrations at Syowa Station, Antarctica, since February 2005. The measured BC concentrations in 2005–2016 were corrected to equivalent BC (EBC) concentrations using Weingartner's method. Seasonal features of EBC concentrations, long-range transport from mid-latitudes to the Antarctic coast, and their origins were characterized. Results show that daily median EBC concentrations were below the detection limit (0.2 ng m−3) to 63.8 ng m−3 at Syowa Station (median, 1.8 ng m−3; mean, 2.7 ng m−3 during the measurement period of February 2005–December 2016). Although seasonal features and year-to-year variations in EBC concentrations were observed, no long-term trend of EBC concentrations was clear during our measurement period. Seasonal features of EBC concentrations showed a spring maximum during September–October at Syowa Station. To elucidate EBC transport processes, origins, and the potential source area (PSA), we compared EBC data to backward trajectory analysis and chemical transport model simulation. From comparison with backward trajectory, high EBC concentrations were found in air masses from the marine boundary layer. This finding implies that transport via the marine boundary layer was the most important transport pathway to EBC concentrations at Antarctic coasts. Some EBC was supplied to the Antarctic region by transport via the upper free troposphere. Chemical transport model simulation demonstrated that the most important origins and PSA of EBC at Syowa Station were biomass burning in South America and southern Africa. Fossil fuel combustion in South America and southern Africa also have important contributions. The absorption Ångström exponent (AAE) showed clear seasonal features with 0.5–1.0 during April–October and maximum (1.0–1.5) in December–February. The AAE features might be associated with organic aerosols and mixing states of EBC.

Combined Pb-Sr-Nd isotopes tracing technique with positive matrix factorization (PMF) analysis was used for source apportionment of metal elements in PM2.5 from Xiamen city, a coastal city in Southeast China. The results showed that the mean concentration of metal elements in PM2.5 in winter was 51.92% higher than that in summer. The air-mass backward trajectory analysis suggested that PM2.5 in Xiamen was significantly influenced by local sources during the sampling period. According to our study, metal elements in PM2.5 were mainly from plating and alloy industry and coal combustion, followed by soil and construction dusts, while traffic exhausts played a minor role. The carcinogenic risk value to human of Cr, Co, Ni and Cd, which mainly came from plating and alloy industry and soil and construction dusts, were exceeded the safe value (10−6), indicating the relative control measures should be taken for the above elements in PM2.5.

This paper estimates the regional contribution of high PM2.5 concentration and associated mortality using HYSPLIT back trajectory analysis in eight Indian cities during 2015–2016. Health risk and mortality estimation were carried out using the Integrated Exposure Response function (IER) which was verified using our previous time series study in Delhi. Risk estimates from IER were observed to be slightly over-predicted (2.14%) when compared to health risk from time series study in Delhi. Health risk in the eight cities across the four seasons indicated higher chronic obstructive pulmonary disease (COPD), lung cancer (LC), ischemic heart disease (IHD), and stroke in the northern (COPD = 1.35, LC = 1.50, IHD = 1.39, Stroke = 2.06) and eastern cities (COPD = 1.27, LC = 1.38, IHD = 1.35, Stroke = 1.93) as compared to in southern or western cities. Risk of stroke was observed to be the highest: North = 1.37–1.52, South = 1.20–1.31, East = 1.40–1.52, and West = 1.24–1.35 times to that of other diseases. Uttar Pradesh was observed to be a major contributor to premature mortality in Delhi, Lucknow, and Patna accounting for 30, 71, and 42% of total premature death due to high PM2.5 concentration during winter. Similarly, high PM2.5 concentration from West Bengal and Bangladesh was responsible for 52% of total premature mortality in Kolkata while the Indian Ocean was a major contributor to premature mortality in western and southern cities during winter. Reduction of both local and regional pollution is required to yield a significant reduction in pollution of all cities except Delhi and Lucknow where regional and local sources respectively are dominant.

Forty-eight PM2.5 samples were collected from June to August 2015 at the summit of Mount Tai. The samples were analyzed to determine the concentrations, potential sources and health risk of organochlorine pesticides (OCPs). Total OCPs concentration in PM2.5 ranged from 20.5 to 331 pg m–3. Hexachlorocyclohexane (HCHs) were the most abundant compounds. The sources of OCPs used potential source contribution function (PSCF), back trajectory analysis and principal component analysis suggested that the southwest agricultural areas and southeast regions of Mount Tai were the significant contributions regions of OCPs. Both old residual and new input were considered to the contribution of OCPs contamination. Human health risk assessment was carried out by non-carcinogenic health hazard quotient (HQ). The HQ values through inhalation and dermal contact ranged from 9.28 × 10–12 to 6.56 × 10–3, indicating a negligible risk of the study area.

In this paper, the emergence phenomenon in the assembly process was studied. First, we constructed the SIRS model of the assembly process and obtained the threshold condition of the extinction of defects through phase trajectory analysis. Second, we discretized the SIRS model and studied the emergence phenomenon during the assembly process. Third, the screening process was added to decrease the basic reproduction number in the SIRS model. It showed that the propagation of defects and emergence phenomenon could be suppressed to some extent through simulations. Finally, we found the relationship between the critical time point and other parameters during the assembly process, which is helpful for the assembly process.

Although Japan has maintained the state of eradication of the oriental fruit fly, Bactrocera dorsalis Hendel complex (Diptera: Tephritidae) since 1986, B. dorsalis complex are occasionally trapped within a limited area and short time period on Japan's small south‐western islands. Trapping events occurred on Amamioshima Island, Kagoshima Prefecture, in 2015, and male adults were also caught in surveillance traps on neighbouring Tokunoshima (south of Amamioshima) and Yakushima (north of Amamioshima) islands as well as on several islands in Okinawa Prefecture (south of Amamioshima). To investigate possible domestic dispersal of the pest from Amamioshima Island, a trajectory analysis was performed to reveal the timing and flight distance of possible dispersal. Surveillance data indicated that the first trappings on Tokunoshima and Yakushima islands occurred in November, which was after the number of trapped male adults on Amamioshima Island peaked in late October. Backward trajectories from Tokunoshima Island beginning 14 days prior to the first trapping passed over Amamioshima Island, which suggested possible dispersal between the islands. Several backward trajectories from the islands in Okinawa Prefecture also passed Amamioshima Island. Moreover, forward trajectories from Amamioshima Island beginning during peak occurrence, from mid‐October to early November, arrived over Tokunoshima, Iheya and Okinawa islands where the flies were caught. Such circumstantial evidence suggests that domestic dispersal of B. dorsalis complex occurred on Amamioshima Island. A situation similar to that on Tokunoshima Island also occurred on Yakushima Island. However, since the number of traps has been limited until the first capture, it was not clear when and from where the immigrants arrived on the island.

Asian dust storms can increase the level of atmospheric pollution over regions downwind of dust storms and may have adverse health effects on residents along the sandstorm transmission route. This study was the first to report the concentration levels, properties and possible sources of environmentally persistent free radicals (EPFRs) and oxidative potential in atmospheric PM2.5 at the three sites of Erenhot, Zhangbei, and Jinan along the transport route of Asian dust storms during the occurrence of Asian dust storms in the spring of 2016. Under non-sandstorm weather conditions, the average EPFR concentrations at the three sites were Zhangbei>Jinan>Erenhot, while the PM-induced oxidative potential levels were Erenhot>Jinan>Zhangbei. The PM2.5 concentration increased significantly during dust storm events, and the total atmospheric concentration of EPFRs (spins/m3) and total oxidation potential (a.u./m3) of PM2.5 simultaneously increased. However, the EPFR concentration in PM2.5 (spins/g) and the unit mass of the PM oxidation potential (a.u./g) were significantly reduced. Electron paramagnetic resonance analysis combined with backward trajectory analysis and MODIS products showed that Asian dust storms can carry EPFRs over long distances. Correlation analysis showed that the atmospheric concentrations of EPFRs were positively correlated with elemental carbon (EC) for the Zhangbei and Jinan samples but were not significantly correlated with EC for the Erenhot samples, indicating that combustion may be an important source of EPFRs for the Zhangbei and Jinan samples. In contrast, the EPFRs in the Erenhot samples were more affected by dust/sand. The EPFR concentration levels showed a significant positive correlation with the oxidation potentials for the Erenhot and Zhangbei samples and showed negative correlations for the Jinan samples, suggesting that the EPFRs in the Erenhot and Zhangbei samples may provide an important contribution to the oxidative stress in PM2.5. In contrast, the oxidation potential for the Jinan samples was mainly caused by substances other than EPFRs. This study presents a basic understanding of the potential health effects of Asian dust storms, and this information can be used to assess the health risks of Asian dust storms in future studies. Keywords: Asian dust storms, EPFRs, Oxidative potential, Transport, Source

International audience; We present CHAMPION (Chalmers hierarchical atomic, molecular, polymeric, and ionic analysis toolkit): a software developed to automatically detect time-dependent bonds between atoms based on their dynamics, classify the local graph topology around them, and analyze the physicochemical properties of these topologies by statistical physics. In stark contrast to methodologies where bonds are detected based on static conditions such as cut-off distances, CHAMPION considers pairs of atoms to be bound only if they move together and act as a bound pair over time. Furthermore, the time-dependent global bond graph is possible to split into dynamically shifting connected components or subgraphs around a certain chemical motif and thereby allow the physicochemical properties of each such topology to be analyzed by statistical physics. Applicable to condensed matter and liquids in general, and electrolytes in particular, this allows both quantitative and qualitative descriptions of local structure, as well as dynamical processes such as speciation and diffusion. We present here a detailed overview of CHAMPION, including its underlying methodology, implementation, and capabilities.

Quasiclassical trajectory analysis is now a standard tool to analyze non-minimum energy pathway motion of organic reactions. However, due to the large amount of information associated with trajectories, quantitative analysis of the dynamic origin of reaction selectivity is complex. For the electrocyclic ring opening of cyclopropyl radical, more than 4000 trajectories were run showing that allyl radicals are formed through a mixture of disrotatory intrinsic reaction coordinate (IRC) motion as well as conrotatory non-IRC motion. Geometric, vibrational mode, and atomic velocity transition-state features from these trajectories were used for supervised machine learning analysis with classification algorithms. Accuracy >80% with a random forest model enabled quantitative and qualitative assessment of transition-state trajectory features controlling disrotatory IRC versus conrotatory non-IRC motion. This analysis revealed that there are two key vibrational modes where their directional combination provides prediction of IRC versus non-IRC motion.

While local anthropogenic emission sources contribute largely to deteriorate metro air quality, long range transport can also play a significant role in influencing levels of pollutants, particularly carbon monoxide (CO) that has a relatively long life span. A nationwide lockdown of two months imposed across India amid COVID-19 led to a dramatic decline in major sources of emissions except for household, mainly from cooking. This initially led to declined levels of CO in two of the largest megacities of India, Delhi and Mumbai under stable weather conditions, followed by a distinctly different variability under the influence of prevailing mesoscale circulation. We hereby trace the sources of CO from local emissions to transport pathways and interpret the observed variability in CO using the interactive WRF-Chem model and back trajectory analysis. For this purpose, COVID-19 emission inventory of CO has been estimated. Model results indicate a significant contribution from externally generated CO in Delhi from surrounding regions and an unusual peak on 17th May amid lockdown due to long range transport from the source region of biofuel emissions in central India. However, the oceanic winds played a larger role in keeping CO levels in check in a coastal megacity Mumbai which otherwise has high CO emissions from household sources due to a larger share of urban slums. Keeping track of evolving carbon-intensive pathways can help inform government responses to the COVID-19 pandemic to prioritize controls of emissions sources.

The pandemic of Coronavirus diseases occurred in the Republic of Korea from 19 January 2020. By March 2020, Korea had reported the second largest number of Coronavirus patients in the world. On the anniversary date (2021), however, with a 51.3 M population, Korea has had 73.115 K patients with 1.283 K deaths, and this stands at 86th in the world. On average, Korea has 14.3 patients per 10,000 people. Air-parcel trajectory analysis and airflows show that in the general westerly region, air parcels and pollutants could flow out and in all directions. This suggests initially that Coronaviruses from source areas in China could transmit to many sink regions and sectors including 228 subdivided counties in Korea. However, there were only relatively small numbers of Coronavirus patients in western sea sides of the Korean Peninsula in comparison with large numbers of Coronavirus disease patients in cities and in eastern sides. In particular, three counties in Korea, including Ong-jin, Mooju and Chang-heung, have zero patients of Coronavirus diseases. This suggests that a long-distance transmission of Coronavirus from Wuhan and other infected cities in China to western Korea likely did not occur. Moreover, there was no evidence on the potential transmission of Coronavirus from neighboring large cities to the above-mentioned isolated counties in Korea which are only 10 ~ 50 km away. In the biosphere, during the transmission stage, the inactivation of Coronavirus by UV rays appeared to occur effectively in 30 ~ 120 min, in agreement with the result of satellite and modeling studies. In turn, the air transmission of Coronaviruses and pollution from China and neighboring cities in Korea apparently had no impact to cause Coronavirus diseases at the 228 counties in Korea. The infection and spreading of Coronavirus diseases to other people in Korea mainly appeared to occur in confined indoor air environments. With the absence and lack of UV rays in indoor environments, Coronaviruses would be active there for hours or days longer than in the outdoor environments.

Siliceous marine microfossils were unexpectedly discovered during the analysis of flower honey samples from Poland and Tunisia. The microfossils were represented by protist with siliceous skeletons: silicoflagellates, diatoms, and endoskeletal dinoflagellates. This is the first record of such microfossils in honeys. Based on the high percent of anemophilous pollen grains and spores in the sample, it was hypothesized that silicoflagellates were deposited from the air onto the nectariferous flowers, then bees harvested them with the nectar. Based on the comparison of pollen content of honeys and flowering calendar of Tunisia, the harvest time of honey was identified as a period between 1 April and 31 May 2011. Trajectory analysis of air masses in this period confirmed that siliceous microfossils could be aerosolized by wind from the rocks of the so-called Tripoli Formation of Messinian age (6–7 Ma). Similar to the Tunisian case, the Polish trajectory simulation also supports the hypothesis of atmospheric transport of silicoflagellates from outcrops of Oligocene age in the Polish Outer Carpathians. In the case of diatom content of honey, however, the source can be both natural (wind) and artificial (diatomaceous earth filters). For a correct determination, natural sources of siliceous bioparticles, such as wind transport from nearby outcrops should be also considered. Silicoflagellates could be used as complementary indicators of the geographical origin of honeys collected in areas characterized by diatomite outcrops, supporting the results obtained with other methods, thus, such indicators merit further studies within the area of honey authenticity.

The Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in March 2011 emitted a considerable amount of radioactive materials. This study isolated radiocesium-bearing microparticles (CsMPs), a form of radioactive materials emitted from the FDNPP at the early stage of the accident, from aerosols collected hourly on filter tapes at seven monitoring stations at the greater Kanto Region, including the Tokyo metropolitan area, on 15 March 2011. The aerosols had a spherical shape ~ 1 μm in diameter with activity of less than 1 Bq of 137Cs per particle. Their physical and chemical characteristics, including radioactivity ratio 134Cs/137Cs as well as chemical composition and state, are essentially the same as previously reported CsMPs. This study demonstrated that air parcels containing CsMPs emitted from the FDNPP were widespread over the greater Kanto Region, more than 250 km away from the FDNPP, during the daytime of 15 March. Trajectory analysis indicated that these particles were emitted from the reactor No. 2 of FDNPP between 14 March evening and 15 March early morning. The information obtained on the widespread distribution of CsMPs can be useful for assessing the actual impacts of radioactive contamination from the FDNPP accident on the environment and human health.

We analyzed the effect of the North American monsoon anticyclone (NAMA) on the meridional transport of summertime cross‐tropopause convective outflow by applying a trajectory analysis to a climatology of convective overshooting tops (OTs) identified in GOES satellite images, which covers the domain from 29°S to 68°N and from 205°W to 1.25°W for the time period of May to September, 2013. From this analysis, we identify seasonal development of geographically distinct outflow regions of convectively influenced air masses (CIAMs) from the NAMA circulation to the global stratosphere and quantify the associated meridional displacement of CIAMs. We find that prior to the development of the NAMA, the majority of CIAMs exit the study area in a southeastern region between 5°N and 35°N at 45°W (75.5% in May). During July and August, when the NAMA is strongest, two additional outflow regions develop that constitute the majority of outflow: 68.1% in a northeastern region between 35°N and 60°N at 45°W and 13.4% in a southwestern region between 5°N and 35°N at 145°W. The shift in the location of most CIAM outflow from the pre‐NAMA southeastern region to NAMA‐dependent northeastern and southwestern regions corresponds to a change in average meridional displacement of CIAMs from 3.3° northward in May to 24.5° northward in July and August. Meridional transport of CIAMs through persistent outflow regions from the NAMA circulation to the global stratosphere has the potential to impact global stratospheric composition beyond convective source regions., Key Points Trajectory analysis of overshooting tops identified by GOES satellite is used to evaluate meridional transport of cross‐tropopause convective outflowThe North American monsoon anticyclone (NAMA) circulation and its seasonality dictates the extent of meridional transport that occurs in the lower stratosphereDuring July and August, when the NAMA is strongest, the average convectively influenced air mass is transported 22.0° northward

The aim of this work is to study precipitation chemistry in the cross-border region between Turkey and Bulgaria, situated on the south-eastern part of the Balkan Peninsula. A total of 115 wet deposition samples were collected and analysed for pH values and major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, and SO42-) throughout the summer and autumn seasons of 2014. The enrichment factor analysis and non-sea salt estimates were conducted to determine the possible sources of ions in the wet deposition for the sampling period. The trajectories of the cyclones affecting the area during the study period were also analysed by separating them in different groups. The minimum, average and maximum pH values for the first group of cyclones (CG1) are 4.30, 6.04, 7.40, and 4.00, 6.14, 7.43 for the second group cyclones (CG2), respectively. The non-sea salt fractions of the K+ ion were found to be 0.94 in CG1 and 0.90 in CG2. Also, the Mg2+ ion in CG1 and CG2 is 44% and 60% of the sea salt source. Bulgaria-Turkey IPA Cross-Border Programme, CCI [2007CB16IPO008-2013-3-025] This study has been carried out within the framework of the Bulgaria-Turkey IPA Cross-Border Programme, CCI Number 2007CB16IPO008-2013-3-025 (SAAP4FUTURE). Special thanks also to Headquarters of Kirklareli Chamber of Agriculture for providing logistic support for the activities in Turkey.

WOS:000614806200005; Ecological research focuses on the spatio-temporal patterns of ecosystems and communities. The recently proposed framework of Community Trajectory Analysis considers community dynamics as trajectories in a chosen space of community resemblance and utilizes geometrical properties of trajectories to compare and analyse temporal changes. Here, we extend the initial framework, which focused on consecutive trajectory segments, by considering additional metrics with respect to initial or baseline states. Addressing questions about community dynamics and more generally temporal and spatial ecological variability requires synthetic and efficient modes of representation. Hence, we propose a set of innovative maps, charts and trajectory roses to represent trajectory properties and complement the panel of traditional modes of representation used in community ecology. We use four case studies to highlight the complementarity and the ability of the new metrics and innovative figures to illustrate ecological trajectories and to facilitate their interpretation. Finally, we encourage ecologists skilled in multivariate analysis to integrate CTA into their toolbox in order to quantitatively evaluate spatio-temporal changes.

Several air pollution episodes occurred in Beijing before and after the 2014 Asia-Pacific Economic Cooperation (APEC) summit, during which air-pollution control measures were implemented. Within this autumn-winter transit season, domestic heating started. Such interesting period merits comprehensive chemical characterization, particularly the organic species, to look into the influence of additional heating sources and the control measures on air pollution. Therefore, this study performed daily and 6h time resolved PM2.5 sampling from the 24th October to 7th December, 2014, followed by comprehensive chemical analyses including water-soluble ions, elements and organic source-markers. Apparent alterations of chemical profiles were observed with the initiation of domestic heating. Through positive matrix factorization (PMF) source apportionment modeling, six PM2.5 sources including secondary inorganic aerosol (SIA), traffic emission, coal combustion, industry emission, biomass burning and dust were separated and identified. Coal combustion was successfully distinguished from traffic emission by hopane diagnostic ratio. The result of this study reveals a gradual shift of dominating sources for PM pollution episodes from SIA to primary sources after starting heating. BaPeq toxicity from coal combustion increased on average by several to dozens of times in the heating period, causing both long-term and short-term health risk. Air mass trajectory analysis highlights the regional influence of the industry emissions from the area south to Beijing. Control measures taken during APEC were found to be effective for reducing industry source, but less effective in reducing the overall PM2.5 level. These results provide implications for policy making regarding appropriate air pollution control measures.

Black carbon (BC) particles being emitted from mobile and stationary emission sources as a result of combustion activities have significant impacts on human health and climate change. A lot of social activities have been halted during the COVID-19 lockdowns, which has evidently enhanced the ambient and indoor air quality. This paper investigates the possible emission sources and evaluates the meteorological conditions that may affect the dispersion and transport of BC locally and regionally. Ground-level equivalent BC (eBC) measurements were performed between January 2020 and July 2020 at a university campus located in Dammam city of the Kingdom of Saudi Arabia (KSA). The fossil fuel (eBCff) and biomass burning (eBCbb) fractions of total eBC (eBCt) concentrations were estimated as 84% and 16%, respectively, during the entire study period. The mean eBCbb, eBCff, and eBCt concentrations during the lockdown reduced by 14%, 24%, and 23%, respectively. The results of statistical analyses indicated that local fossil fuel burning emissions and atmospheric conditions apparently affected the observed eBC levels. Long-range potential source locations, including Iraq, Kuwait, Iran, distributed zones in the Arabian Gulf, and United Arab Emirates and regional source areas, such as the Arabian Gulf coastline of the KSA, Bahrain, and Qatar, were associated with moderate to high concentrations observed at the receptor site as a result of cluster analysis and concentration-weighted trajectory analysis methods.

Anthropogenic pollution from marine microplastic particles is a growing concern, both as a source of toxic compounds, and because they can transport pathogens and other pollutants. Airborne microplastic particles were previously observed over terrestrial and coastal locations, but not in the remote ocean. Here, we collected ambient aerosol samples in the North Atlantic Ocean, including the remote marine atmosphere, during the Tara Pacific expedition in May-June 2016, and chemically characterized them using micro-Raman spectroscopy. We detected a range of airborne microplastics, including polystyrene, polyethylene, polypropylene, and poly-silicone compounds. Polyethylene and polypropylene were also found in seawater, suggesting local production of airborne microplastic particles. Terminal velocity estimations and back trajectory analysis support this conclusion. For technical reasons, only particles larger than 5 µm, at the upper end of a typical marine atmospheric size distribution, were analyzed, suggesting that our analyses underestimate the presence of airborne microplastic particles in the remote marine atmosphere. Airborne microplastic particles with a possible oceanic origin were identified in the marine atmosphere, far from the coast, using micro-Raman spectroscopy analyses of air samples, during a transect across the North Atlantic Ocean in 2016.

The COVID-19 pandemic has drastically affected the economic and social activities, leading to large reductions in anthropogenic emissions on a global scale. Despite the reduction of primary emissions during the lockdown period, heavy haze pollution was observed unexpectedly in megacities in North and East China. In this study, we conducted online measurements of organic aerosol in a background site before and during the lockdown in Guanzhong basin, Northwest China. The oxygenated organic aerosol (OOA) increased from 24% of total OA (3.2 ± 1.6 μg m−3) before lockdown to 54% of total OA (4.5 ± 1.3 μg m−3) during lockdown, likely due to substantial decrease of NOx emissions during lockdown which resulted in large increase of O3 and thus atmospheric oxidizing capacity. OOA showed higher mass concentrations and fractional contributions during lockdown than before lockdown, and increased with the increase of Ox in both periods. In comparison, aqueous secondary organic aerosol (aqSOA) showed high mass concentrations and fractional contributions in both polluted periods before and during lockdown with the increase of aerosol liquid water content (ALWC). The increase of aqSOA under high ALWC conditions is very likely the reason of pollution events during lockdown. Combined with trajectory analysis, the absence of Guanzhong cluster in polluted period during lockdown may play a key role in the OA variations between two polluted periods. In addition, when comparing the clusters from the same transmission directions between before lockdown and during lockdown, the OA fractions showed similar variations during lockdown in all clusters, suggesting the OA variations are widespread in northwest China., Graphical abstract Unlabelled Image

It is a tough challenge for many decades to decipher the complex relationships between cell behaviors and cellular physical properties. Single particle tracking (SPT) with high spatial and temporal resolution has been applied extensively in cell research to understand physicochemical properties of cells and their bio-functions by tracking endogenous or exogenous probes. This review describes the fundamental principles of SPT as well as its applications in intracellular mechanics, membrane dynamics, organelles distribution, and processes of internalization and transport. Finally, challenges and future directions of SPT are also discussed.

This paper introduces novel minimum-deviation control methods to improve step-load transient responses in non-inverting (four-switch) buck-boost dc-dc converters. The approach utilizes all possible switching states to achieve sub-stantial transient response improvements compared to buck-only or boost-only minimum-deviation or time-optimal control (TOC) methods. Using state-plane trajectory analysis, analytical solutions with necessary conditions are developed for step-up and step-down load transient scenarios in both buck and boost modes of operation. An experimental low-voltage prototype intended for mobile applications is used for experimental verification. High effectiveness of the proposed solution is verified by circuit simulations and experiments.

A vessel must navigate along designated routes within a harbor area to ensure navigation safety. The impact of strong currents is one of the most dangerous factors in coastal navigation. However, it is challenging to determine the deviation of a ship in advance from the ship&rsquo, s position data in the case of a marine accident. In this study, to support the decision-making of ship navigators and vessel traffic service (VTS) operators in track monitoring tasks, tracks were classified according to the tidal stream, and the track distribution was analyzed according to the tidal current situations. Marine accident analysis was performed to investigate the tidal influence on ship tracks. Track data were collected for 12 months from a VTS center in Korea, and tidal information was collected through a meteorological observation buoy. Representative tracks were extracted from the track data using the support vector regression (SVR) seaway model. K-fold cross-validation and a grid search were performed to determine the optimal parameters. The ship tracks appeared in specific patterns according to the forces and directions of tidal currents, and specific deviation patterns were observed. This study is expected to contribute to the reduction of marine accidents by predicting ship trajectories according to the tidal situations in advance.