Covid-19: Is the placenta a safe space

Problem: Several large studies have demonstrated that COVID-19 pregnant individuals are at a significant risk for severe disease and adverse pregnancy outcomes. The mechanisms underlying these phenomena remain to be elucidated and are the focus of our project. Although fetal and placental infection is rare, placental abnormalities and adverse pregnancy outcomes associated with placental dysfunction in COVID-19 cases have been widely reported. In particular, placental thrombosis and lesions consistent with maternal vascular malperfusion (MVM) of the placenta are common in individuals with COVID-19. Since thrombotic complications have been associated with COVID-19, it is not surprising that pregnant individuals with COVID- 19 are at risk for placental thrombosis. Method of Study: Placentas were evaluated histologically. Extracellular vesicles were isolated by serial centrifugation. Result(s): Adverse pregnancy outcomes associated with these placental lesions, including hypertensive disorders of pregnancy (gestational hypertension and preeclampsia), small for gestational age (SGA, birthweight < 10th percentile for gestational age), and preterm birth (PTB, < 37 weeks) are significantly increased among pregnant individuals with COVID-19. Placental infection with SARSCoV- 2 is uncommon, but multiple inflammatory and metabolic factors are likely to affect the placenta, including circulating extracellular vesicles (EVs) derived from various organs that have been associated with COVID-19 pathology and disease severity.We have analyzed over 500 placentas from COVID-19 pregnancies and found marked changes in placental morphology, characterized by abnormal maternal and fetal vessels, intervillous thrombi, and fibrin deposition, even in the face of mild or asymptomatic disease. We detected increased levels of small EVs in maternal serum from COVID-19 cases compared to controls and increased levels of mitochondrial DNA in EVs from COVID-19 cases. In in vitro experiments, we found increased oxidative stress in uterine endothelial cells and primary trophoblasts. Syncytialization of trophoblast cells following exposure to EVs from pregnant COVID-19 patients was markedly reduced. RNAseq of trophoblast cells exposed to EVs from pregnant COVID-19 patients revealed disruption of multiple pathways related to mitochondria function, oxidative stress, coagulation defects, and inflammation. Timing of infection during pregnancy (first, second, and third trimester) altered EV size distribution, cargo content, and functional consequences of trophoblast EV exposure. Conclusion(s): Our studies show that COVID-19 infection during pregnancy has profound effects on placenta morphology and function. It remains to be determined what the long-term consequences are on the offspring.

Uniform Gold Nanostructure Formation via Weakly Adsorbed Gold Films and Thermal Annealing for Reliable Localized Surface Plasmon Resonance-Based Detection of DNase-I.

Deoxyribonuclease-I (DNase-I), a representative endonuclease, is an important biomarker for the diagnosis of infectious diseases and cancer progression. However, enzymatic activity decreases rapidly ex vivo, which highlights the need for precise on-site detection of DNase-I. Here, a localized surface plasmon resonance (LSPR) biosensor that enables the simple and rapid detection of DNase-I is reported. Moreover, a novel technique named electrochemical deposition and mild thermal annealing (EDMIT) is applied to overcome signal variations. By taking advantage of the low adhesion of gold clusters on indium tin oxide substrates, both the uniformity and sphericity of gold nanoparticles are increased under mild thermal annealing conditions via coalescence and Ostwald ripening. This ultimately results in an approximately 15-fold decrease in LSPR signal variations. The linear range of the fabricated sensor is 20-1000 ng mL-1 with a limit of detection (LOD) of 127.25 pg mL-1 , as demonstrated by spectral absorbance analyses. The fabricated LSPR sensor stably measured DNase-I concentrations from samples collected from both an inflammatory bowel disease (IBD) mouse model, as well as human patients with severe COVID-19 symptoms. Therefore, the proposed LSPR sensor fabricated via the EDMIT method can be used for early diagnosis of other infectious diseases.

ABS/AgZrP Nanocomposite Additive Manufacturing Filament for Antibacterial Applications

The emergence of COVID-19 raised awareness in hygiene practices and reminded us of the harm that microbes bring to our health. Incorporating antibacterial agents in polymeric materials would allow us to combat lingering bacteria on surfaces that we often use. The utilization of composite filaments with antibacterial activity would allow us to employ better precautions in reducing contact with harmful bacteria. Antibacterial acrylonitrile‐butadiene‐styrene (ABS) nanocomposites were prepared by incorporating silver zirconium phosphate (AgZrP) nanoparticles via twin screw extruder. The ABS/AgZrP nanocomposite filament with 5 wt % and 20 wt% of AgZrP were synthesized and characterized with Differential scanning calorimetry (DSC), Thermogravimetric Analysis (TGA), X-ray diffraction analysis (XRD), and Fourier transform infrared spectroscopy (FTIR). DSC and XRD data denote an increase in the presence of crystalline regions as the AgZrP content is increased. TGA data indicate that the addition of AgZrP has no effect on the thermal stability of the material. FTIR data indicate a decrease in transmission at higher AgZrP loading. The decreasing trend in tensile properties of the 3D-printed neat and AgZrP-filled ABS may have been due to particle agglomeration acting as stress concentrators. Antibacterial activity assessment via disk diffusion test showed a zone of inhibition within the sample indicating that there is no bacterial growth both for Escherichia coli and Staphylococcus aureus. © 2023 Trans Tech Publications Ltd, Switzerland.

Review of Motion Simulation of Particulate Matter in the Respiratory System and Further CFD Simulations on COVID-19

Respirable particulate matter (RSP) is currently very harmful to the human body, potentially causing pulmonary silicosis, allergic rhinitis, acute bronchitis, and pulmonary heart disease. Therefore, the study of the deposition pattern of RSP in the human respiratory system is key in the prevention, treatment, and research of related diseases, whereby the main methods are computer simulation, in vitro solid models, and theoretical analysis. This paper summarizes and analyzes past deposition of RSP in the respiratory tract and also describes them in specific case studies such as COPD and COVID-19 patients, based on the review of the evidence, direction, and focus of future research focusing on simulation, experimentation, and related applications of RSP deposition in the respiratory tract. © 2023 by the authors.

CASE REPORT: FETAL DEATH in UTERO COMPLICATED by DISSEMINATED INTRAVASCULAR COAGULATION in MATERNAL COVID-19 INFECTION

Background: COVID-19 infection during pregnancy is associated with an increased risk of stillbirth, likely due to placental insufficiency through the associated inflammatory response and hypoperfusion. A spectrum of associated placental changes has been reported. Whilst pregnancy alone is a hypercoagulable state, concurrent COVID-19 further increases the risk of coagulopathy. Disseminated intravascular coagulation (DIC) is uncommon in pregnancy but is increased in both COVID-19 infection and fetal death in utero (FDIU). Method(s): Case report. Informed written consent was obtained from the patient. Result(s): A 31-year-old G5P2 presented with a FDIU at 23 + 3 weeks gestation, in the setting of maternal COVID-19 infection without respiratory symptoms or oxygen requirements. The pregnancy had been uncomplicated, and her presenting issue was two days of reduced fetal movements, when FDIU was confirmed on ultrasound. On admission, the case was further complicated by disseminated intravascular coagulopathy (DIC). This DIC could have resulted from COVID-19 infection, FDIU or a combination of both. Placental histopathology showed evidence of inflammation, with chronic histiocytic intervillositis (CHI) and massive perivillous fibrin deposition (MPFD). The inflammatory response, evidenced by histopathological findings of CHI and MPFD, likely contributed to placental insufficiency and FDIU. Conclusion(s): COVID-19 infection is associated with increased risk of hematological abnormalities, placental inflammation and pregnancy loss. This case is the first to report both DIC and CHI in the context of FDIU in COVID-19 infection. We present this case to highlight the impact of COVID-19 infection on placental function, coagulation disturbances and subsequently adverse pregnancy outcomes.

Preface

International Conference on Geospatial Science for Digital Earth Observation (GSDEO 2021)The international conference on "Geospatial Science for Digital Earth Observation” (GSDEO) 2021 was successfully held on a virtual platform of Zoom on March 26th and 27th, 2021. The conference was jointly organized by the Indian Society of Remote Sensing (ISRS), Kolkata chapter, and the Department of Geography, School of Basic and Applied Sciences, Adamas University. Due to the non-predictable behaviour of the COVID-19 second wave, which imposed restrictions on organizing offline events, the GSDEO (2021) organizing committee decided to organize the conference online, instead of postponing the event.Remotely sensed data and geographic information systems have been increasingly used together for a vast range of applications, which include land use/land cover mapping, water resource management, weather forecasting, environmental monitoring, agriculture, disaster management, etc. Currently, intensive research is being carried out using remotely sensed data on the geoinformatics platform. New developments have led to dynamic advances in recent years. The objective of the international conference on Geospatial Science for Digital Earth Observation (GSDEO 2021) was to bring the scientists, academicians, and researchers, in the field of geo-environmental sciences on a common platform to exchange ideas and their recent findings related to the latest advances and applications of geospatial science. The call for papers received an enthusiastic response from the academic community, and over 100+ participants from 50+ colleges, universities, and institutions participated in the conference. In total 50+ research papers had been presented through the virtual Zoom conference platform in GSDEO 2021.The conference witnessed the presentation of research papers from diverse applied fields of geospatial sciences, which include the application of geoinformatics in geomorphology, hydrology, urban science, land use planning, climate, and environmental studies. There were four sessions namely, TS 1: Geomorphology and Hydrology, TS 2: Urban Science, TS 3: Social Sustainability and Land Use Planning, and TS 4: Climate and Environment. Each session was further subdivided, into two parts, namely Technical Session 1-A and 1-B. Each sub-session had been designed with one keynote speech and 5 oral presentations. Oral sessions were organized in two parts and offered through live and pre-recorded components based on the preference of the presenters. The presentation session was followed by a live Q&A session. The session chairs moderated the discussions. Similarly, poster sessions were organized in three parts and offered e-poster, live, and pre-recorded components. The best presenter of each sub-session received the best paper award.Dr. Prithvish Nag, Ex-Director of NATMO & Ex Surveyor General of India delivered the inaugural speech, and Dr. P. Chakrabarti, Former Chief Scientist of the DST&B, Govt. of West Bengal delivered a special lecture after the inaugural session. Eight eminent keynote speakers, Prof. S.P. Agarwal from the Indian Institute of Remote Sensing, Prof. Ashis Kumar Paul from Vidyasagar University, Prof. Soumya Kanti Ghosh from the Indian Institute of Technology, Kharagpur, Prof. L. N. Satpati from the University of Calcutta, Prof. R.B. Singh from the University of Delhi, Dr. A.K. Raha, IFS (Retd), Prof. Gerald Mills from the University College Dublin and Prof. Sugata Hazra from Jadavpur University enriched the knowledge of participants in the field of geoinformatics by their informative lectures. The presentations and discussions widely covered the various spectrums of geoinformatics and its application in monitoring natural resources like vegetation mapping, agricultural resource monitoring, forest health assessment, water, and ocean resource management, disaster management, land resource management, water and climate studies, drought vulnerability assessment, groundwater quality monitoring, accretion mapping and the use of geospatial sci nce in studying morphological, hydrological, and other biophysical characteristics of a region etc. Application of geoinformatics in predicting urban expansion, urban climate, disaster management, healthcare accessibility, anthropogenic resource monitoring, spatial-interaction mapping, and, sustainable regional planning were well-discussed topics of the conference.List of Committees, photos are available in the pdf.

Three-Dimensional Printing Process for Musical Instruments: Sound Reflection Properties of Polymeric Materials for Enhanced Acoustical Performance.

Acoustical properties of various materials were analyzed in order to determine their potential for the utilization in the three-dimensional printing process of stringed musical instruments. Polylactic acid (PLA), polyethylene terephthalate with glycol modification (PET-G), and acrylonitrile styrene acrylate (ASA) filaments were studied in terms of sound reflection using the transfer function method. In addition, the surface geometry parameters (Sa, Sq, Sz, and Sdr) were measured, and their relation to the acoustic performance of three-dimensional-printed samples was investigated. It was found that a higher layer height, and thus a faster printing process, does not necessarily mean poor acoustical properties. The proposed methodology also proved to be a relatively easy and rapid way to test the acoustic performance of various materials and the effect of three-dimensional printing parameters to test such a combination at the very beginning of the production process.

High-Performance Flexible Humidity Sensor Based on MoOX Nanoparticle Films for Monitoring Human Respiration and Non-Contact Sensing

Flexible humidity sensors with high sensitivity, fast response time, and outstanding reliability have the potential to revolutionize electronic skin, healthcare, and non-contact sensing. In this study, we employed a straightforward nanocluster deposition technique to fabricate a resistive humidity sensor on a flexible substrate, using molybdenum oxide nanoparticles (MoOx NPs). We systematically evaluated the humidity-sensing behaviors of the MoOx NP film-based sensor and found that it exhibited exceptional sensing capabilities. Specifically, the sensor demonstrated high sensitivity (18.2 near zero humidity), a fast response/recovery time (1.7/2.2 s), and a wide relative humidity (RH) detection range (0-95%). The MoOx NP film, with its closely spaced granular nanostructure and high NP packing density, exhibited insensitivity to mechanical deformation, small hysteresis, good repeatability, and excellent stability. We also observed that the device exhibited distinct sensing kinetics in the range of high and low RH. Specifically, for RH > 43%, the response time showed a linear prolongation with increased RH. This behavior was attributed to two factors: the higher physical adsorption energy of H2O molecules and a multilayer physical adsorption process. In terms of applications, our sensor can be easily attached to a mask and has the potential to monitor human respiration owing to its high sensing performance. Additionally, the sensor was capable of dynamically tracking RH changes surrounding human skin, enabling a non-contact sensing capability. More significantly, we tested an integrated sensor array for its ability to detect moisture distribution in the external environment, demonstrating the potential of our sensor for contactless human-machine interaction. We believe that this innovation is particularly valuable during the COVID-19 epidemic, where cross-infection may be averted by the extensive use of contactless sensing. Overall, our findings demonstrate the tremendous potential of MoOx NP-based humidity sensors for a variety of applications, including healthcare, electronic skin, and non-contact sensing.

Effects of Precipitation on the Air Quality Index, PM2.5 Levels and on the Dry Deposition of PCDD/Fs in the Ambient Air

The effects of 9 precipitation events in Suzhou City in Anhui Province, China, on the air quality index (AQI), PM2.5, and dry deposition flux of PCDD/Fs (polydibenzo-p-dioxins and polydibenzofurans) were investigated. A total of 7 precipitation events were positive contributes to the reduction of AQI;among them, the AQI were between 23 and 216, with an average of 75, the PM2.5 concentrations were between 5.0 and 169 mu g m-3, with an average of 25 mu g m-3, while the total-PCDD/F-TEQ dry deposition flux ranged from 149 to 1034 pg WHO2005-TEQ m-2 day-1 and averaged 315 pg WHO2005-TEQ m-2 day-1. By comparing the average AQI and PM2.5, respectively, during and after rainfall with that before rainfall, the results indicated that the average reduction fractions of AQI were 26% and 44%, respectively, while those of PM2.5 were 58% and 43%. In addition, the effect of precipitation on the average reduction fraction of total PCDD/F-TEQ dry deposition flux was 31%. However, in the other 2 AQI elevation events, the AQI were between 23 and 100, and averaged 51;when comparing the average AQI and PM2.5 concentrations, during and after the rain with that before the rain, the increases in AQI were 42% and 49%, respectively, while the increases in PM2.5 concentration were 26% and 29%, respectively. The above results show that, on the whole, rain and snow improved the air quality. This is because rainwater removes particles or dissolved gaseous pollutants from the atmosphere and brings aerosols to the ground. However, in some cases, the increase of source emissions and atmospheric vertical convection, the effect of precipitation or air humidity increased the AQI and elevated the concentration of PM2.5, and dry deposition flux of PCDD/Fs. The results of this study provide useful information for both scientific communities and air quality management.

Spread of flushing-generated fecal aerosols in a squat toilet cubicle: Implication for infection risk.

Toilet flushing generates and spread fecal aerosols, potentially leading to infection transmission risk. Squat toilets are widely used in public restrooms in some Asian countries including China and India, and remain to be studied. Aerosol dispersion while flushing squat toilet in cubicle was visualized, while the aerosol concentrations were measured on different surfaces by monitoring fluorescence intensity through seeding simulated fluorescence feces. Flushing-generated fecal aerosols could spread to the breathing zone, deposit on floor, and partitions in squat toilet cubicles, and spread even beyond to the restroom lobby. A total of 0.24 % and 0.17 % of seeded fecal waste deposits on the floor and partition (lower than 0.20 m) for each flush. Aerosol concentration decays rapidly, with 86.8 ± 2.2 % reduction in the second minute after a previous flush compared to that in the first minute. Public toilet users are recommended to wait for 2 min after the early flush before entering the cubicle.

Customizable Fabrication Process for Flexible Carbon-Based Electrochemical Biosensors

In recent research, 3D printing has become a powerful technique and has been applied in the last few years to carbon-based materials. A new generation of 3D-printed electrodes, more affordable and easier to obtain due to rapid prototyping techniques, has emerged. We propose a customizable fabrication process for flexible (and rigid) carbon-based biosensors, from biosensor design to printable conductive inks. The electrochemical biosensors were obtained on a 50 µm Kapton® (polyimide) substrate and transferred to a 500 µm PDMS substrate, using a 3D-extrusion-based printing method. The main features of our fabrication process consist of short-time customization implementation, fast small-to-medium batch production, ease of electrochemical spectroscopy measurements, and very good resolution for an extrusion-based printing method (100 µm). The sensors were designed for future integration into a smart wound dressing for wound monitoring and other biomedical applications. We increased their sensibility with electro-deposited gold nanoparticles. To assess the biosensors' functionality, we performed surface functionalization with specific anti-N-protein antibodies for SARS-CoV 2 virus, with promising preliminary results.

Changes of atmospheric metal(loid) deposition from 2017 to 2021 at Mount Emei under China's air pollution control strategy

Acid deposition and particulate matter (PM) pollution have declined considerably in China. Although metal(loid) and acid deposition and PM have many common sources, the changes of metal(loid) deposition in China in the recent decade have not been well explored by using long-term monitoring. Therefore, we analyzed the dry and wet deposition of eleven metal(loid)s (including Al, As, Ba, Cd, Cu, Cr, Fe, Mn, Pb, Sr, and Zn) from 2017 to 2021 at Mount Emei, which is adjacent to the most economic-developed region in western China (Sichuan Basin (SCB)). Anthropogenic emissions contributed to over 80% of the annual wet deposition fluxes of metal(loid)s and acids (SO4 2-, NO3 -, and NH4 +) at Mount Emei, and the major source regions were the SCB, the Yunnan-Guizhou Plateau, and Gansu Province. Metal(loid) and acid deposition had similar seasonal variations with higher wet deposition fluxes in summer but higher wet deposition concentrations and dry fluxes in winter. The seasonal variations were partially associated with higher precipitation but lower pH in summer (968 mm and 5.52, respectively) than in winter (47 mm and 4.73, respectively). From 2017 to 2021, metal(loid) deposition did not decline as substantially as acid deposition (5.6%-30.4%). Both the annual total deposition fluxes and concentrations of Cr, Cu, Sr, Ba, and Pb were even higher in 2020-2021 than in 2017-2018. The inter-annual and seasonal changes implied the responses of metal(loid) deposition to anthropogenic emission changes were buffered (e.g., transformation, dilution, and degradation) by precipitation rates, acidity, natural emissions, and chemical reactions in the atmosphere, among others.Copyright © 2023 Elsevier Ltd

IAQ in CCU units: an experimental and numerical investigation based on the outlet air height (case study: Namazi Hospital, Shiraz)

Indoor air quality (IAQ) is a significant concern that affects our health. Recent studies show how poor IAQ amplifies the effects of airborne viruses, which endanger the health of the population relative to the COVID-19. This study aims to find the relationship among IAQ, the location of the air outlet valve and the behavior of the IAQ indicators in the cardiac care unit (CCU) at Namazi Hospital, Shiraz, Iran. In this context, the condition of the air outlet valve can play an important part in preparing a better IAQ. To test the hypothesis, articles based on IAQ guidelines have been studied. Also, certain emissions (CO2, CO, PM2.5 and PM10) have been measured, and the relationship between IAQ, the location of the air outlet valve and the behavior of these emissions in the patient's room at Namazi Hospital. This room has been analyzed using computational fluid dynamics for the prediction of the specification of incoming air flow particles. Also, a Eulerian–Lagrangian model was used. In constant, the turbulence model (realizable k–ԑ) and discrete particle model were employed. The results show that when the outlet valve is placed on the wall at 20 cm, it decreased particle deposition in the room, and as a result, IAQ will be improved and at the same time, the chances of transmitting infectious diseases will be reduced. It is also indicated that a higher amount of particle deposition fraction (ca. 0.71) obtains when the outlet valve is located on the top of the wall. © 2023 Informa UK Limited, trading as Taylor & Francis Group.

A versatile 3D printed multi-electrode cell for determination of three COVID-19 biomarkers.

3D-printing has shown an outstanding performance for the production of versatile electrochemical devices. However, there is a lack of studies in the field of 3D-printed miniaturized settings for multiplex biosensing. In this work, we propose a fully 3D-printed micro-volume cell containing six working electrodes (WEs) that operates with 250 µL of sample. A polylactic acid/carbon black conductive filament (PLA/CB) was used to print the WEs and subsequently modified with graphene oxide (GO), to support protein binding. Cyclic voltammetry was employed to investigate the electrochemical behaviour of the novel multi-electrode cell. In the presence of K3[Fe(CN)6], PLA/CB/GO showed adequate peak resolution for subsequent label-free immunosensing. The innovative 3D-printed cell was applied for multiplex voltammetric detection of three COVID-19 biomarkers as a proof-of-concept. The multiple sensors showed a wide linear range with detection limits of 5, 1 and 1 pg mL-1 for N-protein, SRBD-protein, and anti-SRBD, respectively. The sensor performance enabled the selective sequential detection of N protein, SRBD protein, and anti-SRBD at biological levels in saliva and serum. In summary, the miniaturized six-electrode cell presents an alternative for the low-cost and fast production of customizable devices for multi-target sensing with promising application in the development of point-of-care sensors.

Engineering of silk fibroin bio-nanocomposites: A glimpse of advanced research on innovative formulations for potential applications

Silk Fibroin is widely used as a green biomaterial in various fields of research like textiles, biomedical engineering biotechnology, electronics, photonics and energy research. This is because SF can be reconstituted in numerous forms by physical and chemical processes in numbers of studies have attempted to incorporate addition to its unique functional aspects that can be incorporated into SF while maintaining its beneficial natural characters. This new area of biotechnology with bio-nanocomposites is the result of breakthroughs in nanoscience and nanotechnology. SF bio-nanocomposites and their innovative applications for the use of these SF bio-nanocomposites materials have been developed in recent years and these are documented in previous chapters of this book. In this chapter, we report on the advanced research of the engineering of silk fibroin bio-nanocomposites suitable for emerging technologies. Though the formulation of silk fibroin is a natural process, carried out with silkworms, it can be modified with the mulberry leaves which are the silkworm feed. Further, silk fibroin can be changed by doping rare earth elements or by incorporating their nanoparticles at different stages of its formulations. Thus, the properties of silk fibroin are engineered suitably to meet the requirements of various devices with different methods reported recently in the literature. Lastly, the hypothetical applications of silk fibroin in protecting healthcare buildings (hospitals) from pathogenic infections specifically with photocatalytic disinfection of pathogens have been reported in this chapter. This innovative emerging potential application of silk fibroin seems to be an attractive solution to control the spread of communicable diseases like COVID-19. The chapter ends with a report on a recent method based on microwave applications in which formulation of time SF bio-nanocomposites. This modification is reduced synthesis time from 52 hours to 4 hours. This alteration is predicted as a significant step towards commercialization of formulation of SF bio-nanocomposites technologies newly developed in recent years. © 2023 Nova Science Publishers, Inc.

CFD STUDY OF THE INFLUENCE OF SARS-COV-2 DEPOSITION ON HUMAN LUNG DYNAMIC: A COMPARISON BETWEEN HEALTHY AND DISEASED CONDITION

This paper presents a numerical approach to analyze the influence of SARS-CoV-2 deposition on human lung dynamics under real conditions. A comparison is made between a healthy and a diseased lung. A multiphase three-dimensional computational fluid dynamics (CFD) study is performed for the dispersion of covid-19 virus particles throughout the alveolar tree. Then, fully coupled fluid-structure interaction (FSI) is used to evaluate the expansion properties of the alveolar wall. The mesh morphing technique with solid displacement characteristics is used to obtain a realistic wall displacement during the inspiratory and expiratory phases corresponding to the expansion and retraction of the alveolar sac, respectively. These phases are studied under steady-state conditions. The main objective of this study is to evaluate how particle deposition alters the displacement of alveoli exposed to a Sars-Cov-2 and to compare the obtained simulation results with the healthy case. The novelty of this analysis is that it examines where the virus is most deposited and how the presence of Sars-Cov-2 can affect the mechanical properties of the alveolar sac and worsen the respiratory capacity of a sick person at an advanced stage of infection. Copyright © 2022 by ASME.

Positive Matrix Factorization as Source Apportionment of Paddy Soil Heavy Metals in Black Shale Areas in Western Zhejiang Province, China

The source apportionment of pollutants is the key to preventing and controlling the pollution caused by heavy metals in soils. The aim of this study was to investigate the main sources of heavy metals in the soils of black shale areas in western Zhejiang, China. Based on geostatistical spatial analysis, this research employed positive matrix factorization (PMF) for the source apportionment of heavy metals in paddy soil. The results showed that contaminated arable soils were concentrated in the western and southern study areas. At least five major sources of heavy metals were screened in this study: natural sources (39.66%), traffic emissions (32.85%), industrial emissions (9.23%), agricultural activities (9.17%), and mining (9.10%). To be specific, Cd was mainly from mining;As originated from agricultural inputs such as fertilizers and pesticides;and Hg, as an industrial pollutant, was transported by atmospheric deposition in the study area. The accumulation of Pb, Zn, and Cu was mainly influenced by natural sources and anthropogenic sources, i.e., traffic emissions, while that of Cr and Ni was controlled by natural sources.

Study on bioaerosol diffusion and deposition in a mobile BSL-4 laboratory based on air age analysis

Biosafety issues have aroused global concern, especially after the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron strain of corona virus disease 2019 (COVID-19) caused incalculable human and property losses. Laboratory-acquired infections (LAIs) caused by improper operations or accidents are frequently reported. Research is urgently needed for a mobile biosafety level-4 (BSL-4) laboratory with a high risk for exposure. Deposition characteristics and the spatial distribution of bioaerosols under two typical cases were studied in this paper. Based on the age of air and simulation of airflow pattern, a detailed analysis of infection risk and the distribution of bioaerosols was conducted. The deposition characteristics of particles on different surfaces were analyzed based on particle tracking technology. The results showed that the removal rate of bioaerosols was lower in the space area of the laboratory from 1.6 m above the ground. The distribution of high-risk areas is affected by the coupling of equipment layout and pollution sources, mainly located downstream of the main airflow in the laboratory, and the particle concentration was eight times that of the low-risk areas. More than half of bioaerosol particles are deposited on laboratory equipment and walls. The number of particles deposited on the wall was the largest, accounting for 25.02% of the total. The unit area deposition ratio of the experimental table was the highest, which was 6.14 %/m2. The main deposition area of each surface was determined, which could be of guiding significance to the determination of the key disinfection location of the mobile BSL-4 laboratory. © 2023 Elsevier Ltd

PERICARDIAL INVOLVEMENT ASSOCIATED WITH SARS-COV-2 INFECTION. PROSPECTIVE OBSERVATION IN THE COVID- WARD.

Purpose. To identify the occurrence and structure of changes in the pericardium ultrasonography among patients who have undergone COVID-19 and have cardiological symptoms, as well as to compare these changes with the pericarditis aspects and the infection time duration in a prospective cohort observational study. Methods. Inclusion/exclusion criteria: current or transferred COVID-19, new symptoms that occurred during or after infection and forced to consult a cardiologist, the absence of other prerequisites for pericarditis and vaccination against SARS-CoV-2. Echocardiography was performed with an emphasis on the pericardium and an assessment of the echogenicity amplification, the area of the hyperechoic zone, thickness and artifacts, as well as a questionnaire. Results. From 05.2020 to On 10.2020, 335 patients from the covid ward and 284 patients from the out-patient clinic were included. 86% of patients had transient chest discomfort. The peaks of treatment accrued to 4-5 and 10-11 weeks (Me 10[2-36] (1 to 64) weeks) from SARS-CoV-2 infection occurred. Typical ECG changes were registered in 3%, pericardial friction noise - in 7% of patients. In 20% of patients discomfort in the heart area was the first, in 27% - the dominant, in 14% - the only symptom of COVID-19. According to EchoCG data, 96% of the examined patients had ultrasound signs of different changes in the pericardium: slight effusion in 65%, signs of tamponade in 2%, thickening in 12%, local hyperechogenicity in 83%, local adhesion in 8% of patients. The group without pericardial changes was distinguished by the presence of epicardial fat >7 mm. A combination of the echo-cardiography criteria with the second symptom recorded at the visit or earlier was present in 76% of the applicants. Comparison of the recorded ultrasound patterns with the time elapsed since infection allowed us to distinguish ultrasound phases: 1) the phase of damage (pattern of initial edema) occurred at 1 week, 2) the phase of edema /exudation (pattern of visible effusion) - at 3 weeks, 3) fibrosis (pattern of pericardial compaction) - at 11 weeks, 4) regression of inflammatory changes (pattern of local fibrin deposition) - on week 22, 5) residual signs of transferred inflammation may be visualized in patients with symptoms 44 weeks after COVID-19. Conclusions. Consideration of the infectious process triggered by SARS-CoV-2, as a systemic inflammation, allows us to interpret the phenomenon of pericardial involvement as a reactive serositis having ultrasound phases. It was possible to trace some patterns of echocardiography at different stages of the infectious and post-infectious period. Clinical data of 76% of patients can be interpreted as pericarditis, changes in 20% - as an increase in echogenicity of the pericardium.Copyright © 2022 Russian Electronic Journal of Radiology. All rights reserved.