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Fish assemblages are useful in evaluating the health of aquatic ecosystems. Over time, fish assemblages will respond to anthropogenic disturbances but may also simultaneously respond to conservation efforts in a watershed, shifting the taxonomic and functional structure of the assemblage. We quantified temporal changes in taxonomic and functional structure of fish assemblages in the Current River, Missouri, over an 80‐year time span and related these changes to forest regeneration and persistent pasture land use within the watershed. We found shifts in taxonomic and functional assemblage structure in two time‐steps from the 1940s to 2020 related to land use within the watershed. Reforested reaches exhibited increases in benthic species, rheophilic species and invertivorous feeding guilds. Higher pasture reaches exhibited decreases in benthic species and native centrarchid species while generalist centrarchid species increased. Ultimately, fish assemblage structure in the Current River appears to be shifting to an alternative state (i.e. increased presence/abundance of benthic species) in response to forest regeneration and persistent pasture land use. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Yang & Song (2022, https://doi.org/10.1029/2022GL098393) first claimed existence of Earth's inner core differential rotation based on the waveform similarity of two neighboring stations AAK and KZA across an earthquake doublet and then postulated a local velocity gradient at the top of the inner core based on the difference of PKiKP‐PKIKP differential times between the stations and inferred inner core differential rotation rate. In this comment, we collectively analyze the seismic data in the region and add the data of another nearby station HORS into analysis. HORS and KZA, located in an opposite direction away from AAK, consistently exhibit high waveform similarity. Collective analysis of seismic data demonstrates the invalidity of both their logic of claiming existence of inner core differential rotation and their postulation of “a local inner core gradient” to infer differential rotation. Localized and episodic inner core surface change provides a physically consistent explanation to the seismic data.

Based on the observations of hourly precipitation for 131 years from Hong Kong Observatory Headquarters, this study examined the long-term changes in the characteristics of hourly precipitation extremes in terms of intensity, total precipitation amount, duration, and frequency. Results show that the hourly precipitation extremes have significantly intensified by 29%–38% from 1885 to 2022. The 131-year observations evidence that the more extreme the hourly precipitation is (i.e. higher percentiles), the faster the increasing rate it has. Specifically, the magnitudes of hourly precipitation with the 95th, 97.5th, 99th, and 99.9th percentiles increased by rates of 0.03 mm, 0.05 mm, 0.07 mm, and 0.12 mm per year, respectively. Through the secular trend analysis, we found that only the maximum intensity of extreme precipitation events (i.e. events with maximum intensity exceeding the 95th percentiles) shows a significant increasing trend during 1885–2022, while the trends in the total precipitation amount, duration, and mean intensity are not significant. However, by comparing the percentile bin values between three sub-periods of the 131-year record, we found a significant rise over time in the total precipitation amount, mean intensity, and maximum intensity of extreme precipitation events with different intensities (i.e. 95th, 96th, 97th, 98th, and 99th percentiles), while the change in the duration is not significant. The analysis of the frequency of precipitation events shows significant increases in the proportion of extreme precipitation events during 1885–2022. The observations of 53 stations across Hong Kong from 1986 to 2022 show significant intensification and increasing frequency in the hourly precipitation extremes in most areas of Hong Kong. Meanwhile, the precipitation duration shows a decreasing tendency, which may explain the insignificant changes in the total precipitation amount. These findings provide important insights into the longer-term variations in the characteristics of hourly precipitation extremes.

Prenatal infection with the protozoan parasite Toxoplasma gondii can cause congenital toxoplasmosis (CT), an often fatal or lifelong-disabling condition. Several studies of human populations have reported temporal decreases in seroprevalence, suggesting declining CT incidence. However, the consistency of this trend among diverse populations remains unclear, as does its implication for prenatal screening programmes, the major intervention against CT. Using temporally resolved data on the seroprevalence of T. gondii in various countries, we discuss how the parasite's changing epidemiology may affect trends in CT incidence in varying and counterintuitive ways. We argue that parasite stage-specific serology could be helpful for understanding underlying causes of secular changes in seroprevalence. Furthermore, we highlight the importance of updating cost-effectiveness estimates of screening programmes, accounting for neuropsychiatric sequelae. An emerging body of evidence indicates that exposure to Toxoplasma gondii is decreasing among numerous human populations, though most data are from high-income countries. Considering this changing epidemiology, the cost-effectiveness of prenatal screening programmes should be re-examined while accounting for other (not currently considered) sequelae of congenital toxoplasmosis (CT), including possible neuropsychiatric effects. Parasite stage-specific serology should be further developed and applied to serum samples from animals and humans to understand the possible causative mechanisms underlying seroprevalence decreases. The effect of seroprevalence declines on the incidence of CT will be context specific, varying according to parasite genotype, population demographics, and the local epidemiology. [ABSTRACT FROM AUTHOR]

Siwa Oasis is of great historical, environmental, and scientific importance, as it contains unique archeological and geological features. Groundwater is the main source of freshwater in that oasis. The carbonate aquifer groundwater, used for irrigation, was sampled to evaluate factors controlling quality changes spatially and temporally by applying hydrochemical and statistical analyses. The salinity of the aquifer varied spatially from 1367 to 8645 mg/l based on one hydrogeological condition, with the highest TDS (> 5432.5 mg/l, 25% of samples) at the central part of the study area. Temporally, the salinity changed slightly from 3754.3 mg/l (in 2014) to 4222.4 mg/l (in 2020). The cession of illegal wells, pumping control, and excavation of formed salts have a noticeable impact on salinity (mediate the increase in salinity) and ions. However, about 61% of the studied samples can be considered unsuitable for irrigation owing to salinity and can harm plant yield. The heavy metals studied (Fe, Mn, Cu, Pb), except Cd, were within the permissible limit for irrigation water. Finally, it is proposed to construct desalination stations to enhance water quality for irrigation in the study area and set up many companies for salt extraction. [ABSTRACT FROM AUTHOR]

Understanding habitat use and nursery areas of larval fish is a key component to managing and conserving riverine fishes. Yet, freshwater researchers often focus only on adult fishes, resulting in a limited understanding of the habitat requirements for the early life stages of freshwater fishes. The goal of this study was to quantify the larval fish microhabitat use of three fish families in Twelvemile Creek, a fifth-order tributary of Lake Hartwell (Savannah River basin) in the Piedmont ecoregion of South Carolina, USA. We used handheld dipnets to sample larval fishes along 20 equidistant transects spaced 10 m apart weekly from May to July 2021 along a 200 m stream reach. We also collected microhabitat data at each larval fish capture location. Most captured individuals were in the metalarval stage and were identified to the family level. A partial distance-based redundancy analysis indicated that water velocity contributed to changes in larval fish assemblage structure. Larval fishes occupied a subset of the available habitat that was characterized by low water velocity, non-Podostemum substrate, and shallow habitats close to the shore or bed rock structure. We also detected temporal patterns in larval fish counts, with peak Percidae and Leuciscidae counts in late July and the highest Catostomidae counts in late May–early June. Our results suggest that larval fishes select habitats with low water velocity and shallow habitats close to shore microhabitat characteristics, and that riffle-pool sequences may serve as a nursery habitat for Percidae, Catostomidae and Leuciscidae metalarvae. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Medical Imaging & Radiation Sciences is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Previous studies have shown continuous improved overall survival (OS) up to 2015 for young adults with acute lymphoblastic leukaemia (ALL). However, recently several important advances have been made justifying a more contemporary analysis of outcomes in adult with ALL. In this nationwide population-based cohort study, we included patients above 18 years of age diagnosed with ALL between January 1, 1998, and December 31, 2020. Patients were followed until December 31, 2022. By employing flexible parametric survival models, we quantified progress in OS using the key endpoint of 2-year age standardized OS for all patients and clinical subgroups of interest. This study includes 657 patients and demonstrates a significant improvement in OS over time with the 2-year age standardized OS increasing from 36·4 % (95 % CI, 27·0–45·8 %) for patients diagnosed in 1998 to 68·6 % (95 % CI, 60·2–76·9)for patients diagnosed in 2020, corresponding to an absolute increase in 2-year OS of 32·2 % points (95 % CI, 19·1–45·2). Stratified analysis revealed improvements for both Philadelphia chromosome positive and negative ALL, across cytogenetic risk groups, and for B- and T-cell ALL, whereas the latter did not reach statistical significance. Improvements were seen across all ages; however, most pronounced for Philadelphia chromosome positive ALL and patients below 60 years of age. These results show a universal and continuous improvement in the treatment of adult ALL. Currently, novel treatment combination and advances in cellular therapy occur rapidly, and we expect even further improvements in the years to come. Northern Region of Denmark • Previous studies have shown continuous improvement in OS for adult ALL up to 2015. • Since 2015, important novel therapies have been approved, justifying a more contemporary analysis. • In this study we found a 32·2 % points increase in 2-year age standardized OS. • Improvements were seen across all age and cytogenetic risk group, including Ph+ ALL. [ABSTRACT FROM AUTHOR]

The response of marine ammonia-oxidizing archaea (AOA) to environmental stress is reflected in changes in their membrane lipid composition, particularly the unique isoprenoid glycerol dialkyl glycerol tetraethers (iGDGTs). However, the influence of dissolved oxygen (DO) on the composition of iGDGTs in the ocean remains unclear. This study aims to investigate the link between DO levels and the fractional abundances of iGDGTs in the East China Sea (ECS) to establish a redox proxy. Results suggested that the absolute abundances of iGDGTs were influenced by Thaumarchaeota biomass when DO concentrations exceeded 2 mg/L. Vertical distributions of iGDGTs through the water column suggested their transport from bottom waters to sediments. Increasing proportions of iGDGT-0 and the sum of iGDGT-1, iGDGT-2 and iGDGT-3 from suspended particulate matters to surface sediments indicated their preferential preservation. DO concentrations (2–6 mg/L) in the water column showed a significant positive correlation with the relative abundance of crenarchaeol (cren%) but a negative correlation with iGDGT-0%, suggesting insufficient DO levels to promote AOA cyclization. However, bottom DO concentrations exhibited significant negative correlations with both cren% and iGDGT-0% in surface sediments, attributed to enhanced cyclization of iGDGTs and Euryarchaeota abundance within more reducing sediments, respectively. The consistent relationship between iGDGT-0% and DO in both water column and sediments enabled iGDGT-0% to be a potential redox proxy. Temporal variations in iGDGT-0% in the ECS in recent decades aligned well with in-situ DO monitoring data, further validating iGDGT-0% as a promising redox proxy. • Oxygen impact on iGDGTs in the East China Sea was studied to develop a redox proxy. • Thaumarchaeota determined the abundance of iGDGTs when oxygen was available. • Sediment iGDGTs showed preferential preservation of iGDGT-0, −1, −2, −3. • Correlations between iGDGT-0% and DO in water/sediments enabled it as a redox proxy. • iGDGT-0% was used to reconstruct DO changes in the East China Sea in past decades. [ABSTRACT FROM AUTHOR]

AimsTo examine the use of proton pump inhibitors (PPIs) in Scandinavian children with focus on the geographical variation, temporal changes and possible contributing factors to observed changes.MethodsAn observational population-based study of children and adolescents (1-17 years) in Norway, Sweden, and Denmark during the period 2007-2020. Information concerning dispensed PPIs was obtained from the national prescription databases of each country and presented as means per 1,000 children for each country and calendar year in four age categories (1-4, 5-9, 10-13 and 14-17 years).ResultsIn 2007, the PPI use in children was similar across Scandinavian countries. An increased PPI use was observed in all countries during the study period, with gradually increasing differences between the countries. In general, Norway showed both the largest total increase and the largest increase in each age category compared to Sweden and Denmark. In 2020 Norwegian children showed, on average, a 59% higher PPI use compared to Swedish children and a more than double the overall dispensation rate than Denmark. In Denmark there was a 19% reduction in dispensed PPIs from 2015 to 2020.ConclusionDespite being countries with similar health care systems and without indications of increased incidence of gastroesophageal reflux disease (GERD), we observed considerable geographical variation and temporal changes of PPI use in children. Although this study did not contain data on the indication for PPI use, these large differences across countries and time may indicate a current overtreatment.

Globally, freshwater fish diversity is rapidly changing in response to land use change, including urbanization. Time series of freshwater fish communities can help elucidate the underlying mechanisms of species loss and gains, as well as promote conservation strategies. Traditional approaches to understand the dynamics of fish assemblages is traditionally focused on taxonomic diversity, one aspect among many dimensions of biodiversity. Thus, using complementary analytical methods, such as functional diversity, can help researchers to develop a stronger predictive framework on the effects of the species loss or gains in response to urbanization. We assessed temporal changes of fish assemblages in an urban stream in East Texas between four seasonal surveys of 1989–1990 and 2018–2019. We explored the similarities and differences in species richness, composition, and functional diversity of fishes. Although the species richness and functional richness between the two time periods were similar, we observed changes in species composition. We also observed higher functional dispersion and evenness in the 2018–2019 assemblage compared to 1989–1990 assemblage. Some fish species were locally extirpated, while others colonized the system, increasing the functional diversity of the current assemblage. Urbanization has commonly been associated with declines in diversity and richness, however, our findings suggest that the addition of a few invasive generalist species (e.g., blue tilapia) and native tolerant (e.g., redbreast sunfish, blacktail shiner) in this stream system could be associated with increased human activities in this small, urbanized area in East Texas. Streams in East Texas support very diverse fish assemblages, with some sentinel species (e.g., imperiled shiners: Sabine shiner, a habitat-affinity, broadcast spawner) rapidly responding to stream alterations. Multiple stressors can underlie the dynamics and composition of fish assemblages; thus, it is essential for more comparative studies of current and historical data of fish assemblages. Likewise, studies targeting sentinel fish species may have more utility for the evaluation of freshwater ecosystems.

Ransomware is a kind of virus that enciphers data on a victim's machine and only allows it to be decrypted when the user makes the payment. Understanding the strategies employed by cyber thieves is necessary to design effective protection against them. So, an active learning-based digital DNA sequencing engine called DNAact-Ran was developed to predict and identify ransomware data. But, it was not suitable for temporally changed DNA sequences. Hence, this article proposes a deep ensemble ransomware prediction (DeepERPred) model to handle the temporally changed DNA sequences and identify ransomware effectively. In this model, the raw data is converted into the required form. After that, the most relevant attributes are chosen from the preprocessed data using optimization algorithms. The selected attributes are classified by using the ensemble convolutional neural network and long short-term memory (CNN-LSTM) model. This ensemble classification is introduced to handle temporal changes in the DNA sequences by learning dependencies among present and previous occurrences of a sequence for identifying ransomware data. Finally, the investigational outcomes reveal that the DeepERPred model achieves a 90.67% of accuracy, whereas the classical models such as the modified decision tree (MDT), LightGBM, random forest (RF), artificial neural network (ANN), RansomDroid and DNAact-Ran attain 75.83%, 78.52%, 83.22%, 85.48%, 87.91% and 89.14%, respectively to identify ransomware. [ABSTRACT FROM AUTHOR]

Background: Vascular dysfunction is closely associated with the progression of Alzheimer's disease (AD). A critical research gap exists that no studies have explored the in vivo temporal changes of cerebrovascular alterations with AD progression in mouse models, encompassing both structure and flow dynamics at micron-scale resolution across the early, middle, and late stages of the disease., Methods: In this study, ultrasound localisation microscopy (ULM) was applied to image the cerebrovascular alterations of the transgenic female 5×FAD mouse model across different stages of disease progression: early (4 months), moderate (7 months), and late (12 months). Age-matched non-transgenic (non-Tg) littermates were used as controls. Immunohistology examinations were performed to evaluate the influence of disease progression on the β-amyloid (Aβ) load and microvascular alterations, including morphological changes and the blood-brain barrier (BBB) leakage., Findings: Our findings revealed a significant decline in both vascular density and flow velocity in the retrosplenial cortex of 5×FAD mice at an early stage, which subsequently became more pronounced in the visual cortex and hippocampus as the disease progressed. Additionally, we observed a reduction in vascular length preceding diminished flow velocities in cortical penetrating arterioles during the early stages. The quantification of vascular metrics derived from ULM imaging showed significant correlations with those obtained from vascular histological images. Immunofluorescence staining identified early vascular abnormalities in the retrosplenial cortex. As the disease advanced, there was an exacerbation of Aβ accumulation and BBB disruption in a regionally variable manner. The vascular changes observed through ULM imaging exhibited a negative correlation with amyloid load and were associated with the compromise of the BBB integrity., Interpretation: Through high-resolution, in vivo imaging of cerebrovasculature, this study reveals significant spatiotemporal dysfunction in cerebrovascular dynamics accompanying disease progression in a mouse model of AD, enhancing our understanding of its pathophysiology., Funding: This study is supported by grants from National Key Research and Development Program of China (2020YFA0908800), National Natural Science Foundation of China (12074269, 82272014, 82327804, 62071310), Shenzhen Basic Science Research (20220808185138001, JCYJ20220818095612027, JCYJ20210324093006017), STI 2030-Major Projects (2021ZD0200500) and Guangdong Natural Science Foundation (2024A1515012591, 2024A1515011342)., Competing Interests: Declaration of interests The authors declare that they have no conflict of interest., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

The Miyun Reservoir, located in the Miyun District of Beijing, China, is the largest comprehensive water conservancy project in northern China and an important ecological protection area. The combined effects of many factors produce ecosystem changes in the basin; thus, it is important to analyze the spatial and temporal changes that occur here. Based on multi-source satellite remote sensing data, we analyzed changes in water body area, water level height, and water storage in the Miyun Reservoir from 2013 to 2022 and determined whether these changes were natural or caused by human activity. As traditional water body area extraction methods can misidentify buildings and mountainous areas as water bodies, we fused multiple deep learning models (U-Net and SegNet) using the adboost method, which combined the advantages of the basic models and achieved an overall recognition accuracy of > 90 %. Using annual variations in water storage at the reservoir, we determined that the water body area increased to 157.58 km2 between 2013 and 2022, nearly doubling in size, which corresponded to decreases in cultivated land and vegetated areas. Cultivated land is the main land use type affected by water body erosion. The overall water level height exhibited an upward trend (cumulative increase of 14.8 %), eventually reaching 146.11 m. The water storage volume also increased over time, with a cumulative increase of approximately 436 million m3. On this basis, the influences of temperature, precipitation, and human activity on the spatial and temporal variability of the Miyun Reservoir basin were analyzed. The findings have important implications for global change research within and outside the ecosystem.

Aim: Due to the importance of the relationship between air pollutants and the incidence of many diseases in polluted cities, in this study, we collected the data related to yearly, seasonally, monthly, daily, and hourly concentrations of particulate matter (PM) 2.5, PM10, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ozone (O3) recorded at four monitoring stations across Karaj city, Iran, to investigate the air pollutant trends based on air quality indexes (AQIs) in the city during 2012–2018. Materials and Methods: The correlations between PMs and gaseous pollutants were analyzed using the Pearson correlation coefficient. The concentrations of air pollutants indexes including O3, NO2, SO2, CO, PM10, and PM2.5 were recorded in four air pollution monitoring stations in Karaj obtained from the monitoring system of the environment department. Then, the data were analyzed using SPSS and Graph pad softwares. Results: The findings showed that in 20%–40% and 1%–5% of days during 2012–2018, higher concentrations of PM2.5 and PM10 were experienced than the national standard (NS) concentration, respectively. Furthermore, during this time, 0.3%–0.9% of days indicated the higher concentrations of CO and SO2 than the NS, respectively. Although the daily concentration of NO2 was lower than NS, 0.5%–5% of days were exposed to the higher concentration of O3 than NS. SO2 concentration showed a negative and positive correlation with PM10 (r = −0.69, P = 0.013) and O3(r = 0.58, P = 0.03), respectively. Conclusion: These results indicated that Karaj AQI was moderate and the most problem with air quality in Karaj city was attributed to the PM2.5 concentrations. To reduce health disorders related to this pollutant, it is necessary to control PM2.5 sources and sensitive groups should reduce outdoor activities.

This study used catch/effort (CPUE) and length-frequency (L/F) data to evaluate the status of 26 fish species in the mangroves of the Dongzhaigang National Reserve, Hainan Province, China, sampled in 2009 (16 species), 2014 (18 species) and 2020 (15 species) using CPUE and the length-based Bayesian biomass (LBB) method. The CPUE, both in number and weight, was lower in 2009 than in 2014 and lower again in 2020, with the 2009 low attributed to pollution due to shrimp, pig and duck farming within the reserve. Of the 26 fish species assessed, four experienced a large reduction of length from 2009 to 2020, and nine exhibited a decline in the ratio of current biomass to biomass at carrying capacity (B/B0), which is expressed as the 'biomass left'. This ratio was, for most species, below 0.5 in 2009, which suggests that overfishing occurred in 2009 and that it has since become worse. Thus, while the CPUE data provided ambiguous results, the L/F data analyzed by the LBB method demonstrated unambiguously that 'miniaturization' through overfishing is occurring among the exploited 26 fish species from the mangroves of the Dongzhaigang National Reserve. For the fisheries in the mangals of Dongzhaigang Bay to remain viable, fishing effort should be reduced by local governments working with the affected communities, just as they reduced pollution a decade ago. [ABSTRACT FROM AUTHOR]

Analysis of the distribution of abundance and activity of bacterioplankton in the estuary area of the Ob River in July 2016 and September 2013, as well as environmental factors, made it possible to distinguish between riverine, brackish water, and marine zones. In summer, the abundance of bacterioplankton varied from 2604 ± 436 × 103 cells/mL in brackish waters to 468 ± 91 × 103 cells/mL in seawater. The average values of bacterial production in waters with a salinity of less than 8 and more than 22 PSU were 17.43 and 4.91 mgC m–3 day–1, respectively. In autumn, the bacterial abundance decreased towards the sea from 1289 ± 385 × 103 cells/mL in freshwaters to 85 ± 37 × 103 cells/mL in the offshore part; the value of production decreased by more than an order of magnitude. With an increase in salinity, the proportion of cells with active electron transport chain in the abundance of bacterioplankton decreased from 5.8 to 0.6%. Thus, the distribution of river runoff, marked by salinity, proved to be the main factor affecting the spatial distribution and activity of bacterioplankton. However, the mechanism of such regulation remains unclear. [ABSTRACT FROM AUTHOR]

Abstract Background Intestinal parasitic infections are amongst the most common infections worldwide and have been identified as one of the most significant causes of morbidity and mortality among disadvantaged populations. This comparative cross-sectional study was conducted to assess the prevalence of intestinal protozoan infections and to identify the significant risk factors associated with intestinal parasitic infections in Laghouat province, Southern Algeria. Methods A comparative cross-sectional study was conducted, involving 623 symptomatic and 1654 asymptomatic subjects. Structured questionnaires were used to identify environmental, socio demographic and behavioral factors. Stool specimens were collected and examined using direct wet mount, formalin-ether concentration, xenic in vitro culture and staining methods. Results A highly significant difference of prevalence was found between symptomatic (82.3%) and asymptomatic subjects (14.9%), with the majority attributable to protozoan infection. The most common species in the symptomatic subjects were Blastocystis spp. (43.8%), E. histolytica/dispar (25.4%) and Giardia intestinalis (14.6%) and more rarely Enterobius vermicularis (02.1%), Teania spp. (0.6%) and Trichuris trichiura (0.2%), while in asymptomatic population Blastocystis spp. (8%), Entamoeba coli (3.3%) and Entamoeba histolytica/dispar (2.5%) were the most common parasites detected with no case of helminth infection. Multivariate log-linear analysis showed that contact with animals was the main risk factor for transmission of these protozoa in both populations. Furthermore, living in rural areas was significantly associated with combined protozoan infection in the asymptomatic population, whereas, in the symptomatic population an increasing trend of protozoan infection was detected in the hot season. In addition, Blastocystis spp. and G. intestinalis infection were found to be associated with host sex and contact with animals across the study period. Conclusions Based on these results, several strategies are recommended in order to effectively reduce these infections including good animal husbandry practices, health education focused on good personal hygiene practices and adequate sanitation.

Redfish (Sebastes mentella and S. fasciatus) are back at spectacular record high levels in the Gulf of St. Lawrence (GSL) and the effects of this massive resurgence on other components of the food web remain largely unknown. To better understand the trophic implications of the surging redfish biomass within the GSL ecosystem, 3,690 stomachs containing food were collected during two periods: one characterised by low redfish abundance (1993–1999) and the other during a period of record abundance (2015–2019). Taxonomical analysis of stomach contents from individuals of different sizes from three subareas of the GSL was carried out to determine diet composition during both periods. Zooplankton represented the main prey category for small redfish (< 20 cm), which was driven by a predation on amphipods, mostly Themisto sp. in North-East Gulf, in the 1990s and on copepods of the genus Calanus in the deep channels and euphausiids in North-West Gulf in the 2010s. Themisto sp. still dominated the diet of medium (20–30 cm) redfish in the 1990s while the copepods were predominant during the 2010s. Shrimp consumption increased with redfish size and two species were particularly important in large redfish diet (≥ 30 cm) during both periods: pink glass shrimp (Pasiphaea multidentata), mostly in the Laurentian Channel and northern shrimp (Pandalus borealis), especially in North-East Gulf. Redfish predation on shrimp represents a major concern for the dynamics of the northern shrimp which supports a valuable fishery in the GSL but has been declining in abundance since several years. Piscivory was observed in large redfish diet, with capelin (Mallotus villosus) being the major fish prey in the 1990s and redfish (cannibalism) in the 2010s, suggesting density-dependent control at high density of small redfish. By presenting a detailed overview into the redfish diet composition and its temporal variability, the present study offers a first look into the possible future trophic impacts of a resurging groundfish in the GSL ecosystem.

Abstract Background Aedes japonicus japonicus has expanded beyond its native range and has established in multiple European countries, including Belgium. In addition to the population located at Natoye, Belgium, locally established since 2002, specimens were recently collected along the Belgian border. The first objective of this study was therefore to investigate the origin of these new introductions, which were assumed to be related to the expansion of the nearby population in western Germany. Also, an intensive elimination campaign was undertaken at Natoye between 2012 and 2015, after which the species was declared to be eradicated. This species was re-detected in 2017, and thus the second objective was to investigate if these specimens resulted from a new introduction event and/or from a few undetected specimens that escaped the elimination campaign. Methods Population genetic variation at nad4 and seven microsatellite loci was surveyed in 224 and 68 specimens collected in Belgium and Germany, respectively. German samples were included as reference to investigate putative introduction source(s). At Natoye, 52 and 135 specimens were collected before and after the elimination campaign, respectively, to investigate temporal changes in the genetic composition and diversity. Results At Natoye, the genotypic microsatellite make-up showed a clear difference before and after the elimination campaign. Also, the population after 2017 displayed an increased allelic richness and number of private alleles, indicative of new introduction(s). However, the Natoye population present before the elimination programme is believed to have survived at low density. At the Belgian border, clustering results suggest a relation with the western German population. Whether the introduction(s) occur via passive human-mediated ground transport or, alternatively, by natural spread cannot be determined yet from the dataset. Conclusion Further introductions within Belgium are expected to occur in the near future, especially along the eastern Belgian border, which is at the front of the invasion of Ae. japonicus towards the west. Our results also point to the complexity of controlling invasive species, since 4 years of intense control measures were found to be not completely successful at eliminating this exotic at Natoye.

Diatoms of the genus Pseudo-nitzschia are producers of the neurotoxin domoic acid that causes serious damage to marine fauna and aquaculture farms. These microalgae are known as the most abundant group of toxic phytoplankton in Peter the Great Bay, Northwestern Sea of Japan, during the bloom season, which, as was previously reported for members of this group in the study region, lasts in the autumn months. Autumnal blooms of toxic diatoms Pseudo-nitzschia spp. were studied in the period from 2017 to 2022 in Ussuri Bay, the largest body of water in Peter the Great Bay, which harbors numerous recreational area and aquaculture farms. As a result, the following changes in the composition of bloom-forming species were recorded: blooms were caused by the Pseudo-nitzschia delicatissima group in the period from 2017 to 2020 and by P. multistriata in 2021–2022. An assumption has been made that one of the factors responsible for blooms of P. multistriata, known as one of the most widespread species in Asian warm-water areas, is an abnormally high water temperature in the autumn of 2021 in the study area.

We provide evidence that the prior quarter earnings number is an important and informative benchmark that is relatively unexplored in the accounting literature. Our analyses suggest that managers appear to avoid negative earnings changes relative to the prior quarter. Moreover, we find that even after controlling for the information contained in other frequently used benchmarks (i.e., analysts' forecasts and earnings from the same quarter of the prior year), changes over the prior quarter's earnings are associated with stock returns. We find that this result is stronger post‐Regulation FD and XBRL, perhaps as a result of the improved information environment. We also find that the informativeness of prior quarter earnings is greater for firms with less volatile earnings and that meeting‐or‐beating prior quarter earnings are associated with future performance. [ABSTRACT FROM AUTHOR]

Background: The biomarker S100B is used for the rule-out of intracranial lesions in patients with mild traumatic brain injury (TBI) and is suggested for prehospital use in Europe. Early kinetics of S100B are not exhaustively investigated in human TBI. This post hoc descriptive study of the data from the PreTBI studies aimed to characterize the early temporal changes of S100B using two-sample timepoints. Materials and Methods: Two consecutive blood samples were taken prehospital and in-hospital after injury and assayed for S100B. The endpoint adjudication of the outcome intracranial lesion was done by the evaluation of electronic medical patient journals. The data were analyzed using descriptive statistics, scatterplots, and temporal changes estimated by the locally weighted scatterplot smoothing (LOWESS) regression line. Results: A total of 592 adult patients with TBI were included; 566 with Glasgow Coma Scale (GCS) 14-15, 20 with GCS 9-13, and 6 with GCS 3-8. Intracranial lesions were diagnosed in 44/566 (7.4%) of patients. In 90% of patients, S100B concentrations decreased from prehospital to in-hospital sampling. The mean decrease was−0.34 μg/L. S100B concentrations seem to decline already within 60 min. Patients sampled very close to trauma and patients suffering intracranial lesions may express a slight incline before this decline. Temporal changes of S100B did not differ in patients >65 years of age, in antiplatelet/-coagulant treatment, alcohol intoxicated, or suffering extra-cranial injuries. Conclusion: S100B concentrations may peak earlier than expected from previous studies of temporal changes in human TBI. Patterns of S100B stand robust to parameters stated as limiting factors to the use for early rule-out of intracranial lesions in the current guidelines. Further studies are needed to investigate the ultra-early temporal profiles of other novel TBI biomarkers to assess prehospital applicability and optimal diagnostic performance in TBI. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer, previously reported as relatively rare in Nigeria, is currently the leading cancer and leading cause of cancer-related death in men. Late presentation appears to persist despite higher incidence rates and instituted awareness programs. This study assesses current prostate cancer indices at presentation to a 3rd tier referral hospital in South-east Nigeria and compares these indices with reported indices from previous decades. Materials and Methods: Retrospectively, the medical records of men presenting with histologically confirmed prostate cancer from January 2009 to April 2018 were reviewed. Age, spectrum and duration of clinical features, serum total prostate-specific antigen (tPSA), and prostate biopsy specimen Gleason Score (GS) at presentation were retrieved for the analysis using the SPSS software version 21. Obtained mean values and proportions were compared to reports from previous decades for observable shifts. Results: The medical records of 331 men 51–90 years of age (mean: 69.8 ± 8.0 years) were retrieved. Six (1.8%) men (median tPSA = 28.0 ng/ml; range 10.0–121.4 ng/ml) had screening-detected prostate cancer. About 72.0%, 52.0%, and 30.3% of men present with symptoms after 3 months, 6 months, and 12 months, respectively, and about 55.1% had other clinical features of disease progression beyond lower urinary tract symptoms. Symptom duration, serum tPSA (median 31.4 ng/ml; range 4.0–710.0 ng/ml), and % fPSA (median 20.6%; range 57.1%–8.6%) at presentation, as well as prevalent poorly-differentiated tumor (GS ≥7 [4 + 3] 62.2%) are yet to shift from reports from previous decades. Conclusions: Prostate cancer indices at presentation in South-eastern Nigeria, a resource-poor community in sub-Saharan Africa are yet to positively shift despite efforts at prostate cancer awareness. [ABSTRACT FROM AUTHOR]

The surface freshwater volume discharged into the Gorgan Bay is a significant part of its ecological processes. The Ghareh-Sou River is the most crucial source of surface freshwater in the Gorgan Bay watershed. It is necessary to investigate the temporal changes of surface freshwater volume series at this river's outlet to the bay. In this study, changes in surface runoff volume discharged by the Ghareh-Sou River into the Gorgan Bay (seasonal and annual time series in 1971–2018) were studied using generalized additive models for location, scale and shape (GAMLSS). Probability distribution functions, including normal, gamma, Gumbel, Weibull, and log-normal as well as six different models were applied to estimate variance and mean changes. This study indicated that the dominant probability distribution function of the studied series was gamma. All annual and seasonal series showed significant non-stationary behavior. The magnitudes of the upper quantiles' changes were more powerful than the lower ones, indicating the importance of investigating the different quantiles' changes. The differences between different quantiles of annual, spring, autumn, and winter series of surface freshwater volume series were increasing. Moreover, the GAMLSS showed the suitable ability to estimate the variation over time, contributing to a deeper understanding of changes in surface freshwater volume time series discharged into the Gorgan Bay. Moreover, changes in climatic variables and human activities were driving factors of the revealed trends in freshwater volume series. [ABSTRACT FROM AUTHOR]

Understanding the degree to which deterministic and stochastic processes drive community assembly is an ongoing focus of research in community ecology. This effort is strongly biased towards ground‐rooted plants, resulting in a limited understanding of communities of other life‐forms, such as structurally dependent plants. Vascular epiphytes are sessile organisms growing non‐parasitically on three‐dimensional dynamic patches, their host plants. Since negative biotic interactions are thought to play a minor role in vascular epiphyte assembly, in some forests, epiphytes are fascinating model organisms to understand the prevalence of environmental filtering in shaping community assembly.We assessed the contribution of deterministic processes on the temporal dynamics of vascular epiphyte assemblages by tracking the direction of changes in composition, species richness and abundance in time at different ecological and spatial scales. We made use of a globally unique dataset from a lowland forest in Panama. We predict that if niche‐based mechanisms dominate, (a) temporal changes will be directional and (b) differences in the species composition of epiphyte assemblages will be primarily related to host plant characteristics and, to a lesser degree, to the distance between host trees.We show that temporal changes in vascular epiphyte assemblages were directional at different ecological scales, such as the forest patch, host species or individual tree assemblages. Epiphyte assemblages on host trees became more similar in their composition over time than expected by chance, and these changes were not due to homogenisation. While host characteristics were related to these directional changes, host structure rather than host identity was more strongly related to variation in assemblage dissimilarity, while spatial distance among trees was of minor importance. The observed directionality was primarily due to environmental filtering.This study provides the first evidence that niche‐based mechanisms dominate the dynamics of vascular epiphyte assemblages. Analysing temporal patterns of vascular epiphyte assemblages is a first important step towards understanding the relative importance of deterministic processes for diversity maintenance of one of the most diverse plant groups in the tropics.Synthesis. Directionality in the temporal changes of epiphyte assemblages suggests that niche‐based mechanisms dominate these temporal changes. Host size over host identity is the most important environmental filter for epiphyte assemblages establishment. [ABSTRACT FROM AUTHOR]

One of the most intriguing features of the Earth's inner core is its temporal variability over decadal time scale. Time-varying sesismic waves traversing the inner core, from high-quality repeating earthquakes, provide unequivocal evidence for the feature. However, the mechanism of the temporal change remains in debate. There have been two competing models, differential rotation of the inner core shifting its lateral heterogeneities and the rapid localized changes of the inner core boundary (ICB). Recent studies suggest that the time-varying seismic waves originate from the interior of the inner core, rather than the ICB. Consequently, the model of differential rotation provides so far the simplest and most reasonable explanation. Inner core is inferred to rotate at the rate of 0.05～0.1 degree per year, with the possibility of decadal fluctuation. The model can reconcile all the time-varying signals observed in previous studies. The investigations on the temporal change of the inner core and its mechanism shed lights on understanding the inner workings of our planet, especially the operation of the geodynamo.

Abstract Background Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2, and outbreaks have occurred worldwide. Laboratory test results are an important basis for clinicians to determine patient condition and formulate treatment plans. Methods Fifty-two thousand six hundred forty-four laboratory test results with continuous values of adult inpatients who were diagnosed with COVID-19 and hospitalized in the Fifth Hospital in Wuhan between 16 January 2020 and 18 March 2020 were compiled. The first and last test results were compared between survivors and non-survivors with variance test or Welch test. Laboratory test variables with significant differences were then included in the temporal change analysis. Results Among 94 laboratory test variables in 82 survivors and 25 non-survivors with COVID-19, white blood cell count, neutrophil count/percentage, mean platelet volume, platelet distribution width, platelet-large cell percentage, hypersensitive C-reactive protein, procalcitonin, D-dimer, fibrin (ogen) degradation product, middle fluorescent reticulocyte percentage, immature reticulocyte fraction, lactate dehydrogenase were significantly increased (P

BackgroundThe biomarker S100B is used for the rule-out of intracranial lesions in patients with mild traumatic brain injury (TBI) and is suggested for prehospital use in Europe. Early kinetics of S100B are not exhaustively investigated in human TBI. This post hoc descriptive study of the data from the PreTBI studies aimed to characterize the early temporal changes of S100B using two-sample timepoints.Materials and MethodsTwo consecutive blood samples were taken prehospital and in-hospital after injury and assayed for S100B. The endpoint adjudication of the outcome intracranial lesion was done by the evaluation of electronic medical patient journals. The data were analyzed using descriptive statistics, scatterplots, and temporal changes estimated by the locally weighted scatterplot smoothing (LOWESS) regression line.ResultsA total of 592 adult patients with TBI were included; 566 with Glasgow Coma Scale (GCS) 14-15, 20 with GCS 9-13, and 6 with GCS 3-8. Intracranial lesions were diagnosed in 44/566 (7.4%) of patients. In 90% of patients, S100B concentrations decreased from prehospital to in-hospital sampling. The mean decrease was−0.34 μg/L. S100B concentrations seem to decline already within 60 min. Patients sampled very close to trauma and patients suffering intracranial lesions may express a slight incline before this decline. Temporal changes of S100B did not differ in patients >65 years of age, in antiplatelet/-coagulant treatment, alcohol intoxicated, or suffering extra-cranial injuries.ConclusionS100B concentrations may peak earlier than expected from previous studies of temporal changes in human TBI. Patterns of S100B stand robust to parameters stated as limiting factors to the use for early rule-out of intracranial lesions in the current guidelines. Further studies are needed to investigate the ultra-early temporal profiles of other novel TBI biomarkers to assess prehospital applicability and optimal diagnostic performance in TBI.

Ciliates are pivotal components of the marine microbial food web, exerting profound impacts on oceanic biogeochemical cycling. However, the temporal dynamics of ciliate assemblages on a short time scale in the highly fluctuating estuarine ecosystem remain largely unexplored. We studied changes in the ciliate community during a short time frame in the high salinity waters (>26) of a subtropical estuary. Ciliate abundance, biomass, size and oral diameter structure, and community composition fluctuated considerably and irregularly over a few days or even a few hours. Spearman correlations and the generalized linear model revealed that heterotrophic prokaryotes (HPs) and viral abundances drove the dynamics of ciliate abundance and biomass. The structural equation model further identified a major path from the high-fluorescence content virus (HFV) to HPs and then ciliates. Given the substantial correlation between salinity and HPs/HFV, we proposed that the response of HPs and HFV to salinity drives the dynamics of ciliate biomass. Additionally, the Mantel test showed that phytoplankton pigments such as Lutein and Neoxanthin, phosphate, and pigmented picoeukaryotes were key covariates of the ciliate community composition. This study demonstrated the highly changing patterns of ciliate assemblages and identified potential processes regulating ciliate biomass and community composition on short timescales in a subtropical, hydrographically complex estuary. [ABSTRACT FROM AUTHOR]

The research of European urban flora is still based on the study of Western and Central European settlements, while relatively few data are available from the southern and eastern parts of Europe. This paper presents the first grid-based approach that surveyed the spontaneous and sub-spontaneous flora and its temporal changes of a Hungarian city located in this latter region of Europe. The changes during 70 years in the flora of a Hungarian county seat, Pécs were investigated. The contemporary city areas were used as two different study areas in the analyses. Changes in species richness, proportions of dispersal types, life form traits and alien statuses were examined during the mentioned period. With 1641 vascular plant species found at 232.88 km2 in the last 70 years, the flora of Pécs represents a diversity hotspot within Europe. In contrast with other European cities we found significant (19.37%) increase in the number of species over the last 70 years. As a result of temporal changes in the city flora, differnces were found only in the case of neophytes' life forms regardless of the spatial approach. Similar to the other cities globally the number of woody species neophytes and short-lived alien plants increased. [ABSTRACT FROM AUTHOR]

Summary: Although new learning is known to reappear in later dream scenarios, the timing of such reappearances remains unclear. Sometimes, references to new learning occur relatively quickly, 1 day post‐learning (day‐residue effect); at other times there may be a substantive delay, 5–7 days, before such references appear (dream‐lag effect). We studied temporal delays in dream reactivation following the learning of a virtual reality (VR) flying task using 10‐day home sleep/dream logs, and how these might be influenced by targeted memory reactivation (TMR). Participants were exposed twice to a VR task in the sleep laboratory; once before and once after a 2‐hr opportunity to nap (n = 65) or to read (n = 32). Auditory cues associated with the VR task were replayed in either wake, rapid eye movement (REM) sleep, slow‐wave sleep (SWS) or were not replayed. Although we previously showed that TMR cueing did not have an immediate effect on dream content, in the present study we extend these results by showing that TMR in sleep has instead a delayed effect on task–dream reactivations: participants dreamed more about the task 1–2 days later when TMR was applied in REM sleep and 5–6 days later when it was applied in SWS sleep, compared to participants with no cueing. Findings may help explain the temporal relationships between dream and memory reactivations and clarify the occurrence of day‐residue and dream‐lag phenomena. [ABSTRACT FROM AUTHOR]

The amount of time we spend online has been increasing dramatically, influencing our daily travel and activity patterns. However, empirical studies on changes in the extent to which the amount of time spent online are related to changes in our activity and travel patterns are scarce, mainly due to a lack of available longitudinal or quasi-longitudinal data. This paper explores how the relationships between the time spent using the Internet, and the time spent on non-mandatory maintenance and leisure activities, have evolved over a decade. Maintenance activities include out-of-home activities such as shopping, banking, and doctor visits, while leisure activities include entertainment activities, visiting friends, sporting activities, and so forth. Our approach uses two datasets from two major cross-sectional surveys in Scotland, i.e. the 2005/06 Scottish Household Survey (SHS) and the 2015 Integrated Multimedia City Data (iMCD) Survey, which were similarly structured and formed. The multiple discrete–continuous extreme value (MDCEV) model and difference-in-differences (DD) estimation are applied and integrated to examine how the relationships between the time spent on the Internet and travel have changed over time and the direction and magnitude of the changes. Our findings suggest that the complementary associations between Internet use and individuals' non-mandatory activity-travel time use are diminishing over time, whereas their substitutive associations are increasing. We additionally find that such temporal changes are significant in the case of those who spent moderate to high levels of time on the Internet (5 h or more online) per week. [ABSTRACT FROM AUTHOR]

The spatiotemporal reflectance fusion method is used to blend high-temporal and low-spatial resolution images with their low-temporal and high-spatial resolution counterparts that were previously acquired by various satellite sensors. Recently, a wide variety of learning-based solutions have been developed, but challenges remain. These solutions usually require two sets of data acquired before and after the prediction time, making them unsuitable for near-real-time predicting. The solutions are always trained band by band and thus do not consider the spectral correlation. High-resolution temporal changes are difficult to reconstruct accurately with the network structure used, which lowers the accuracy of the fusion result. To address these problems, this study proposes a novel spatiotemporal adaptive reflectance fusion model using a generative adversarial network (GASTFN). In GASTFN, an end-to-end network, including a generative and discriminative network, is simultaneously trained for all spectral bands. The proposed model can be applied to the one-pair case, consider the spectral correlation of each band, and improve the process of producing super-resolution imagery by adopting the discriminative network for image reflectance values rather than temporal changes in reflectance. The proposed model has been verified with two actual satellite data sets acquired in heterogeneous landscapes and areas with abrupt changes, with a comparison of the state-of-art methods. The results show that GASTFN can generate the most accurate fusion images with more detailed textures, more realistic spatial shapes, and higher accuracy, demonstrating that the GASTFN is effective for predicting near-real-time changes in image reflectance and preserves the most valuable spatial information. [ABSTRACT FROM AUTHOR]

This paper evaluates the seasonal changes of microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) contents as an indicator of urban soil health. Our research was conducted in six horticultural urban soils in Krakow that have been cultivated for centuries. We investigated the temporal dynamics of microbial biomass C and N in soil samples from 0 to 20 cm depth taken in spring, summer and autumn. The study plots were placed in suburban areas as well as in the centre of the city to distinguish whether the detected effect of altered soil properties is similar to suburban areas. Soil microbial biomass was determined by the chloroform fumigation–extraction (CFE) method. The concentrations of MBC and MBN were measured in the field‐moist soil samples. MBC in the soil ranged from 226.5 to 742.7 mg kg−1 and MBN from 62.7 to 359.6 mg kg−1 expressed in dry mass. Repeated‐measures analysis of variance (ANOVAR, match‐model) was performed to test the main effects and interactions of temporal changes for MBC and MBN. There were significant differences only between MBN concentration in summer and autumn (p <.05). Principle component analysis (PCA) gave insightful results for the whole soil profile. Detrended canonical correspondence analysis (DCCA) indicated that the most explanatory variables in the studied time period were concentration of silt, total nitrogen, MBN and MBC content in the surface layer. Molar ratios of total organic carbon and total nitrogen (TOC:TN) indicated that microbial activity for C and N is enhanced by stoichiometry demands and therefore may be important for vegetation. [ABSTRACT FROM AUTHOR]

One complex task involving sequence of movements and movement refinement in the rat is the single‐pellet reaching task, comprising orientation, transport and withdrawal in sequence. In turn, orientation comprises front wall detection, slot localization and nose poke until reach start. Video recordings of a rat in the reaching box highlighted three stages of temporal training: start of training (ST), forepaw dominance appearance (D) and fully trained (T). Regarding orientation, ST versus D and T presented a significant smaller frequency of approach to the front wall and a significant higher number of whisker cycles and nose touches during slot localization, involving a significant longer Orientation. At the ST stage, 44% of the trials were interrupted after nose poke, and poke took place at significant higher level from the shelf. The shelf was identified only when short whiskers contacted it, but the tongue and both forepaws were used without distinction to reach and grasp the pellet until a forepaw emerged as dominant at D stage. Regarding the temporal features of transport and withdrawal, comparing the D versus T stage revealed a significant longer duration. Finally, successes were significantly higher in T respect to D, meaning that after dominance emergence, more training was still necessary to improve reaching/grasping performance. This study provides evidence that, during training, the rats develop a strategy to obtain the pellets and then refine their movement pattern. [ABSTRACT FROM AUTHOR]

Changes in vegetation cover affects local climatic conditions and brings changes surface biomass. Vegetation change studies became significant indicators for global climate change, drought conditions and to study crop health. The normalized difference vegetation index (NDVI), which is anexcellent indicator for measuring vegetation health, stressed vegetation anddeforestation and droughtconditions. Time series of NDVI will give crop growth profiles. Satellite observations are used to produce global scale vegetation cover statistics. These NDVI based statistics bring comprehensive geographical and seasonal patternsof vegetation and surface energy balance. NDVI derived from remote-sensing data by measuring reflectance values in RED and Infrared regions, using Google Earth Engine. Sentinel-1(ESA) and Landsat8 data used to derive temporal variability of Normalized Difference Vegetation Index (NDVI). The study was carried out for a period of 2008, 2013 and 2019 in VMRDA region. Studybrings out vegetation statistics like vegetation cover changes, deforestation, and crop health in the study area. Thus, NDVI has a multidimensional indicator and has also been used for land cover classification, drought monitoring, vegetation health, crop stress, land degradation and forest carbon dynamics. [ABSTRACT FROM AUTHOR]

Abstract Background COVID-19 has become a national and an international pre-occupation to all doctors. Dealing with patients with clinical suspicion of COVID-19 is a daily markedly growing professional issue for radiologists. The number of COVID-19 cases we deal with is peaking since last March and so is our experience in recognizing the disease patterns and in assessing its severity. The purpose of this study is to assess the role of CT chest in the diagnosis of COVID-19 based on our experience with 220 Egyptian cases. Results A cross-sectional multicenter study involving 220 patients; 68 (30.9%) females and 152 (69.1%) males, their age range was 10-92 years (average 49.198 years). Non-contrast MSCT chest was done to patients with clinically suspected COVID-19. Data assessment and analysis for lesions probability, pattern, localization, and severity were done. Bilateral affection was seen in 168/220 cases (76.36%). Multilobar affection was noted in 186/220 cases (84.54%). Lower lobes affection was noted in 179/220 cases (81.36%). Peripheral/subpleural affection was noted in 203/220 cases (92.27%). The common CT patterns (ground-glass opacities, consolidation, crazy paving, vascular thickening, traction bronchiectasis, vacuolar sign, architectural distortion signs, and reversed halo sign) and the uncommon CT patterns (halo sign, masses, nodules, lobar affection, tree in-bud-pattern and cysts) were discussed. Associated extra-pulmonary lesions described. Temporal changes, severity scoring, reporting, and possible pitfalls were all assessed. Conclusion In our experience, CT plays a basic essential role in diagnosing COVID-19 in the current declared pandemic.