Respiratory aerosol transmission represents an important pathway for the spread of infectious diseases in indoor educational environments. Real-time monitoring of respiratory droplets was performed using the AeroDrops respiratory droplet detector in multiple educational settings, including kindergarten and a primary school classroom, a university lecture hall, and experimental chemistry workshops. Measurements were conducted under different environmental conditions, including different ventilation regimes, seasonal conditions, and groups of preschool children, school children, and young adults. The detector selectively detected respiratory droplets while remaining insensitive to particulate matter and other non-respiratory aerosol sources. Distinct temporal variations in droplet concentrations were observed which correlated with participant activities, occupancy levels, vocalization, and movement. The results demonstrate that selective real-time monitoring of respiratory droplets provides information unavailable from conventional indoor air quality indicators and offers a promising approach for ventilation management and indoor air safety assessment.

Abstract Cryogenic transmission electron images of small cellular particles isolated from conditioned media of microalgae Dunaliellatertiolecta are presented Each image is supplemented by description of the preparation of the sample and the data on the imaging technique and equipment. Keywords: Extracellular vesicles, Extracellular particles, Nanoalgosomes, Exosomes

Abstract : Scanning electron microscope images of small cellular particles isolated from Phaeodactylum tricornutun conditoned media , light and dark phases are presented . Each image is supplemented by description of the preparation of the sample and the data on the imaging technique and equipment. Keywords: Extracellular vesicles, Extracellular particles, Nanoalgosomes, Exosomes

Abstract: Scanning electron microscope images of small cellular particles isolated from conditioned media of microalgae Dunaliella tertiolecta are presented . Each image is supplemented by description of the preparation of the sample and the data on the imaging technique and equipment. Keywords: Extracellular vesicles, Extracellular particles, Nanoalgosomes, Exosomes

Abstract:Scanning electron microscope images of small cellular particles isolated from conditioned media of microalgae Phaeodactylum tricornutum are presented Each image is supplemented by description of the preparation of the sample and the data on the imaging technique and equipment. Keywords: Extracellular vesicles, Extracellular particles, Nanoalgosomes, Exosomes

Abstract : Scanning electron microscope images of small cellular particles isolated from conditioned media of microalgae Phaeodactylum tricornutun are presented . Each image is supplemented by description of the preparation of the sample and the data on the imaging technique and equipment. Keywords: Extracellular vesicles, Extracellular particles, Nanoalgosomes, Exosomes

Small cellular particles (SCPs) are being considered for their role in cell-to-cell communication. We harvested and characterized SCPs from spruce needle homogenate. SCPs were isolated by differential ultracentrifugation. They were imaged by scanning electron microscope (SEM) and cryogenic transmission electron microscope (cryo TEM), assessed for their number density and hydrodynamic diameter by interferometric light microscopy (ILM) and flow cytometry (FCM), total phenolic content (TPC) by UV-vis spectroscopy, and terpene content by gas chromatography-mass spectrometry (GC-MS). The supernatant after ultracentrifugation at 50,000× g contained bilayer-enclosed vesicles whereas in the isolate we observed small particles of other types and only a few vesicles. The number density of cell-sized particles (CSPs) (larger than 2 μm) and meso-sized particles (MSPs) (cca 400 nm–2 µm) was about four orders of magnitude lower than the number density of SCPs (sized below 500 nm). The average hydrodynamic diameter of SCPs measured in 10,029 SCPs was 161 ± 133 nm. TCP decreased considerably due to 5-day aging. Volatile terpenoid content was found in the pellet after 300× g. The above results indicate that spruce needle homogenate is a source of vesicles to be explored for potential delivery use.

Outfitting the P,P & PRIME;-distereogenic 2MeBigFUS ligand with the characteristic branched/functionalized-alkoxy feature of the R-SMS-Phos design furnished the 2RBigFUS family (Figure 2). Rhodium(I) complexes thereof exhibited a further boosted activity and superior enantioselectivity in the hydrogenation of various functionalized olefins, including the challenging & alpha;-arylacrylic acids. The application under practical conditions to enantiomeric active pharmaceutical ingredients (APIs) and relevant synthetic building blocks capped the outcome. Multipurpose hydrogenation catalysts, endowed with a top-performance under economical conditions, is the outcome of Knowles' DiPAMP evolved version. Bulky rather than super-thin Ligand models seem to fit better for a broader scope of Rh(I)-L catalysis. Application to enantiomeric & alpha;- or & beta;-amino acids, & alpha;-arylpropionic acids, & beta;-phenylbutanoic acid, methylsuccinic acid, and derivatives, is showcased.image

Transition-metal-complex-catalyzed asymmetric hydrogenation of archetypal beta-amido beta-(methyl or phenyl)-acrylates (and close derivatives) into the corresponding enantioenriched beta-amido propionates is reviewed. The literature reports (including patents) on efficient enantiopure P,P-ligand-enabled catalytic systems-wherein the P,P-ligand is a cis-chelating diphosphine-are juxtaposed under their disclosed testing conditions per substrate along with the scored enantioselectivity. Such a listing clearly reveals their relative performance and constitutes a practical guide to inspire future development.

Particulate matter (PM) is classified as one of the most dangerous air pollutants which cause numerous adverse health effects. Prolonged exposure to high PM concentrations can lead to se-rious health complications and severe chronic conditions. Our research work is focused on the concentration of PM particles in ambient air. We studied how the concentration changes with different seasons (summer and autumn). The results of our experimental work show that the concentration of PM in the air increased during the colder period of the year. In autumn, the av-erage daily mass concentration was determined at 0.85 μg/m3, which means it was over the daily limit set by the WHO. These results indicate that the level of air pollution has a detrimental im-pact on human health in Ljubljana, the capital city of Slovenia. Due to strong impacts of PM par-ticles on our body, we further studied the impact of PM10 particles on human blood erythrocytes, with the aim of interdisciplinary synthesis of knowledge from the scientific fields like environ-mental protection and medicine. The results of in vitro studies show that a prolonged exposure to increasing concentration of PM10 particles causes a decrease in erythrocyte population. We also observed changes in membrane shapes when erythrocytes were exposed to PM particles for a longer time. We also observed the transition from echinocyte to stomatocyte cell shape with help of a scanning electron microscope (SEM). The results of this research can be used as a basis for more extensive research on the systemic impact of inhaled PM particles on the human body.

Saccharin is an organic compound, which is often used as a calorie-free artificial sweetener. It salts are being produced for the market for over 80 years. Saccharin and its derivates are very applicatory oriented, therefore researchers synthesize more and more active ingredients, which could potentially show better performance. This work considers the effect of biological activity of a newly synthesized saccharin derivative Me- thyl 4-hydroxy-1,1-dioxo-2H-1,2-benzothiazine-3-carboxylate (6Sac) on yeast Saccharomyces cere-visiae. Qualitative comparison of the studied activity with the activity of the saccharine sodium salt is presented. Our results were gained by two different ways of viability detection: counting dead/live cells dyed with methylene blue and counting colony-forming units (CFU). The study has shown that the saccharine derivative with an ester functional group has negative effect on growth and repro-duction of yeast. The qualitative comparison of the activity of the tested substance with the already known activity of saccharine sodium salt is a convenient method for following the model organism Saccharomyces cerevisiae. Keywords: Saccharin, sodium saccharinate, Saccharomyces cerevisiae, Viability, Methylene blue, Col-ony-forming units (CFU), Medicine

Feline hyperthyroidism is a disorder resulting from excessive concentrations of thyroid hormones in the systemic circulation.Parenteral application of radioiodine 131 I is the treatment of choice, but it can cause iatrogenic hypothyroidism.To minimalize that risk, algorithms for individual doses and prognosis factors have been suggested.Treatment of hyperthyroidism can worsen a pre-existing renal condition, therefore, renal function should always be assessed pre-and post-treatment.To make this treatment more available and widespread, oral administration of 131 I has been suggested.This contribution reviews the latest contributions on this subject and compares them to what is already known about the treatment of feline hyperthyroidism with radioactive iodine.

Extracellular vesicles (EVs) are membrane-enclosed structures of nanometer dimensions. They are formed by cells and can be found in isolates from body fluids. It is indicated that they play important role in intercellular communication in health and disease. In this work we observed the morpholoical parameters of EVs isolated by differential centrifugation from washed erythrocytes, in which vesiculation was accelerated by addition of detergent (sodium dodecyl sulfate). Aliquots of the isolate were suspended medium of two different osmolarities. Isolates were imaged with a scan-ning electron microscope (SEM) and the images were analyzed by using the contours of EVs from which the volume V, surface area S, and relative volume v = (36S3/V2)1/2 were assessed by a geomet-rical model. EVs were considered as spheres or spheroids. The isolates were rich in erythrocyte EVs so that representative sets (86 vesicles at osmolarity of 50 mOsmol/L and 109 vesicles at osmolarity of 300 mOsmol/L) could be outlined. The EVs at osmolarity of 50 mOsmol/L had shapes close to a sphere, while at osmolarity of 300 mOsmol/L they had elongated shapes. The shapes were approxi-mated by prolate spheroids. The average volume/surface area of EVs at osmolarity 50 mOsmol/L were 3.18×105 nm3/2.20×104 nm2, and at osmolarity 300 mOsmol/L they were 4.3×105 nm3/2.79×104 nm2. The respective differences in favor of the values at 300 mOsmol/L were statistically significant and of sufficient power. The relative volume of EVs at 50 mOsmol/L and 300 mOsmol/L were 1 and 0.96, respectively. While the difference in v suggests that, similarly to erythrocytes, water enters EVs in order to attain the Donnan equilibrium, the differences in V and A suggest that selective popping of (larger) EVs in the hypoosmolar sample took place. Keywords: Extracellular vesicles; Erythrocytes; Osmolarity; Differential centrifugation; Scanning electron microscopy (SEM); Morphology; Interdisciplinary connection; Medicine

Background: Cells in general secrete nanoparticles (NPs) which are believed to mediate intercellular communication. Recently, great efforts have been made to utilize them as delivery vectors. We aimed to harvest and identify NPs from liquid cultures of two marine microalgae Dunaliella tertiolecta and Phaeodactyum tricornutum. Methods: NPs were isolated from the culture conditioned media by differential ultracentrifugation by the protocol used for the isolation of extracellular vesicles. Microalgae and isolated NPs were examined by scanning electron microscopy (SEM) while isolated NPs were examined also by cryogenic transmission electron microscopy (cryo-TEM). The Triton X-100 detergent and temperature sensitivity of NPs was assessed by dynamic light scattering (DLS) through monitoring the intensity of the scattered light (I) and the distribution of hydrodynamic radii of NPs (Rh). Results: Two mechanisms of formation of NPs with average Rh 200 nm were observed in the D. tertiolecta culture: a disintegration of tubular protrusions, and cell decay. A part of the imaged D. tertiolecta NPs were membrane-enclosed vesicles, but the isolates also contained electron-dense NPs and nanofilaments. P. tricornutum NPs in the culture and in the isolate were homogeneous in size and shape. Their average Rh was 104 nm. The addition of surfactant to isolates resulted in a change in Rh distribution and a decrease of I in samples from both species, indicating decay of a part of NPs. Changes in the width of the I(Rh) peaks were observed at temperatures above 45 °C. Conclusions: A part of NPs found in isolates from microalgae D. tertiolecta and P. tricornutum were membrane-enclosed vesicles. However, the isolates obtained by a standard protocol for extracellular vesicle isolation by ultracentrifugation contained also a significant amount of other similar-sized nanoparticles. The isolates were partly susceptible to the addition of detergent and to temperature up to 80 degrees.

Small cellular particles are released into the surroundings of cells and are proposed to play an important role in intercellular communication and consequently the responses of microbial com-munities to environmental stressors. We studied the connection between the small cellular parti-cles and the efficiency of three culture series of the microalge Phaeodactylum tricornutum and bac-teria (axenic microalgae, bacterial culture and co-culture of the two) in removing bisphenols from their growth medium. The microorganism growth rate was determined by flow cytometry, protein profiles were examined by protein gel electrophoresis, cultures and small cellular particle isolates were imaged by scanning electron microscopy, and bisphenols were analyzed using gas chroma-tography coupled with tandem mass spectrometry (GC-MS/MS). Higher growth rates of microal-gae were observed in the co-culture than in the axenic microalgal culture, while the presence of bisphenols neither influenced the morphology of the microalgal cells, protein profiles, nor the small cellular particle isolates. Biotic removal of bisphenols ranged from 0% to 71% and differed among the culture series in a compound-specific manner. However, it remains unclear which mechanisms influenced algal growth and bisphenol removal. Further research on the mechanisms of interspecies communication is needed to advance our understanding of microbial communities at the nano-level.

Raw data on dynamic light scattering assessment of small cellular particles isolated from conditioned culture media of microalgae Dunaliella tertiolecta (D. tertiolecta) and Phaeodactylum tricurnutum (P. tricornutum) by dynamic light scattering are presented. The project contains spreadsheet files with the measured dependencies of g2 function on time. We collected several g2 functions for each setting (3 for D. tertiolecta samples, 5 for D. tertiolecta with added TX100, 3 for P. tricornutum samples, 3 for P. tricornutum with added TX100). Curves were analyzed independently and compared with the respective averaged curve fitted by the inverse Laplace transform program CONTIN (freely available at: http://s-provencher.com/index.shtml, the code was accessed 25. 1. 2011). The correlation curves were fitted with up to 50 exponents. For analysis of stability of small cellular particles with respect to temperature change, we have overall reports for each microalgae type and reports on the size distribution function, data for the g2 function and dependence of scattered light intensity on time for each temperature measured. There were 14 temperatures chosen for each type of microalgae. The files are marked with respective temperatures. The samples were prepared as described below: Cultivation of the algae: Cultures of D. tertiolecta CCAP 19/22 and P. tricornutum CCAP 1052/1A from the Culture Collection of Algae and Protozoa (CCAP) of SAMS (Oban, Scotland) were grown in artificial seawater (Reef Crystals, Aquarium Systems, France). 22 g of salt was dissolved in one litre of distilled water, sterile filtered (0.2-micron cellulose filters, ref. 11107-47-CAN, Sartorius Stedim Biotech GmbH, Germany), autoclaved, and supplemented with Guillard’s (F/2) Marine Water Enrichment Solution (ref. G0154, Sigma Aldrich, USA). Cultures were grown in a respirometer (Echo, Slovenia) in 0.5-L borosilicate bottles, at 20 °C and 20 % illumination (approximately 250 μmol/m2s) with a 14-hour light / 10-hour dark cycle, with aeration of 0.2 L/min. Isolation of small cellular nanoparticles: Small cellular particles were isolated by differential centrifugation, using a protocol widely used for the isolation of extracellular vesicles (Théry C, Amigorena S, Raposo G, Clayton A. Isolation and Characterization of Exosomes from Cell Culture Supernatants and Biological Fluids. Current Protocols in Cell Biology. 2006;30(1). doi:10.1002/0471143030.cb0322s30). Microalgal cells were removed by low-speed centrifugation (300 g, 10 min, 4°C, centrifuge Centric 260R with rotor RA 6/50 (Domel, Slovenia)), using 50 mL conical centrifuge tubes (ref. S.078.02.008.050, Isolab Laborgeräte GmbH, Germany); and 2000 g, 10 min, 4°C (Centric 400R centrifuge with rotor RS4/100 (Domel, Slovenia)), using 15 mL conical centrifuge tubes (ref. S.078.02.001.050, Isolab Laborgeräte GmbH, Germany). Each step was repeated twice. Then, the cell-depleted medium was centrifuged twice at 10 000g and 4°C for 30 min (Beckman L8-70M ultracentrifuge, rotor SW55Ti (Beckman Coulter, USA)), using thin-wall polypropylene centrifuge tubes (ref. 326819, Beckman Coulter, USA) to remove larger cell debris. Finally, small cellular particles were pelleted by centrifugation at 118 000 g and 4°C, for 70 min in the same type of ultracentrifuge and ultracentrifuge tubes. The isolate obtained from about 30 mL of conditioned media was not visible to the eye. For treatment with Triton X-100, the sample was incubated with Triton X-100 at concentration of 0.1%. Dynamic light scattering (DLS): The average hydrodynamic radius (Rh) of NPs and the average intensity of scattered light (I) were assessed for characterization of small cellular particles by DLS. The value of I was interpreted as a measure of small cellular particles concentration (in the case of preserved particle size distribution) or as a topological change (in the case of altered particle size distribution)(Paterna A, Rao E, Adamo G, et al. Isolation of Extracellular Vesicles From Microalgae: A Renewable and Scalable Bioprocess. Front Bioeng Biotechnol. 2022;10:836747. doi:10.3389/fbioe.2022.836747; Brown W, ed. Dynamic Light Scattering: The Method and Some Applications. Clarendon Press ; Oxford University Press; 1993). For analysis of the samples we used Instrument 3D-DLS-SLS cross-correlation spectrometer from LS Instruments GmbH (Fribourg, Switzerla nd) with a 100 mW DPSS laser (Cobolt Flamenco, Cobolt AB, Sweden) having a wavelength λ0 = 660 nm. Before measurements, samples were equilibrated in a decalin bath at 25 °C for 15 min. The scattered light was measured at an angle θ = 90° for 120 s. The correlation functions and integral time-averaged intensities I(θ)≡ I(q) (where q is the scattering vector, defined as q =(4πn0/λ0)sin(θ/2), with n0 the refractive index of the medium, in our case estimated by the corresponding value for water, i.e. n0 = 1.33 at 25°C), were recorded simultaneously. The Rh values of small cellular particles were obtained from the diffusion coefficients (D) that were assessed from the correlation function of the scattered electric field (g1(t)). The g1(t) function was calculated from the measured correlation function of the scattered light intensity g2(t) by applying Siegert’s relation (Schärtl W. Light Scattering from Polymer Solutions and Nanoparticle Dispersions. Springer; 2007; Shurer CR, Kuo JCH, Roberts LM, et al. Physical Principles of Membrane Shape Regulation by the Glycocalyx. Cell. 2019;177(7):1757-1770.e21. doi:10.1016/j.cell.2019.04.017). To convert D to Rh, the Stokes-Einstein equation was used (Rh = kT6πηD, where k is the Boltzmann constant, T is the absolute temperature, and η is the viscosity of the medium in which the particles diffuse). It was assumed that particles have a spherical shape. The viscosity of the medium was not known. We approximated the viscosity value to that of of water at 25°C.To test the effect of Triton X-100 on the samples, 0.1% (V/V) of Triton X-100 was added to the sample before the measurement. The change in Rh distribution and the change of scattered light intensity (ΔI = Isample - Isample+0.1%.TX100) was determined. The analysis was made with an in-house created software based on the inverse Laplace transform program CONTIN (freely available at: http://s-provencher.com/index.shtml, the code was accessed 25. 1. 2011). We collected several intensity correlation functions for each setting. Curves were analyzed independently and compared with the averaged curve. The correlation curves were fitted with up to 50 exponents. To test the effect of Triton X-100 on NPs, 0.1% (V/V) of Triton X-100 was added to the sample before the measurement. The change in Rh distribution and the change of scattered light intensity (ΔI = Isample - Isample+0.1%.TritonX-100) was determined. Thermal stability analysis was performed using the LitesizerTM 500 instrument (Anton Paar GmbH). Samples were heated from 15 °C to 80 °C in 5 °C steps. When the target temperature was reached, the samples were equilibrated for another 5 minutes before 10 measurements of 20 s duration were performed. The size distributions were determined from the mean correlation function using the Anton Paar Kalliope Professional; Version 2.16.0. (Anton Paar GmbH), https://www.anton-paar.com/corp-en/products/details/software-for-particle-analysis-kalliopetm/, applying the CONTIN approach. A new version of KalliopeTM 4.12.0 https://www.kalliope.com/2021/05/03/versione-firmware-4-12-0/?lang=en is freely available online.

Special purpose acquisition companies (SPAC) have become an increasingly popular way for private companies to go public due to their flexibility and ease in regulatory procedures. SPAC is in essence a blank check company with no business operations and assets (apart from cash and cash equivalents after the initial public offering (IPO)) that is formed with a purpose of acquiring a certain private company or companies. SPAC’s initial public offering proceeds in the United States in 2021 have surpassed those of 2020 and have just passed 160 billion dollars. Merger activity of SPACs and target companies has been especially intense in sectors of technology and healthcare. This scientific con-tribution analyzes IPO proceedings and total enterprise values (TEV) data for SPACs in the healthcare sector in the US and portrays a comparison with the technology sector.

In this contribution, we present the findings of our research on informal economic activity in the service sector during the pandemics of COVID-19. We found that approximately 28% of respondents were engaged in informal economic activity, while the most commonly purchased services were accommodation and food service activities and administrative and support service activities. Our results show that the primary reasons for such engagement were directly linked to the pandemics of COVID-19, which is an important finding for decision-makers. Based on the results of the research we believe that consumer habits have not shifted towards regular engagement in informal economic activities. Respondents also showed a general supportiveness of informal economic activities of ser-vice providers during the pandemics and lockdowns, which might indicate a dissatisfaction with the government restrictions on business activities. With the use of the Pearson chi-squared test, we found no association between the sex of the respondents and their engagement in the informal economic activity or their opinion on the legitimacy of service providers' activities during the pandemics and lockdowns. Keywords: Informal economic activity; Grey economy; Service sector; Survey; Association

We studied the efficiency of three culture series of the microalgae Phaeodactylum tricornutum (P. tricornutum) and bacteria Thalassospira sp. (axenic microalgae, bacterial culture and co-culture of the two) in removing bisphenols (BPs) from their growth medium. Bacteria were identified by 16S ribosomal RNA polymerase chain reaction (16S rRNA PCR). The microorganism growth rate was determined by flow cytometry. Cultures and isolates of their small cellular particles (SCPs) were imaged by scanning electron microscopy (SEM) and cryogenic transmission electron microscopy (Cryo-TEM). BPs were analyzed by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). Our results indicate that some organisms may have the ability to remove a specific pollutant with high efficiency. P. tricornutum in axenic culture and in mixed culture removed almost all (more than 99%) of BPC2. Notable differences in the removal of 8 out of 18 BPs between the axenic, mixed and bacterial cultures were found. The overall removals of BPs in axenic P. tricornutum, mixed and bacterial cultures were 11%, 18% and 10%, respectively. Finding the respective organisms and creating microbe societies seems to be key for the improvement of wastewater treatment. As a possible mediating factor, numerous small cellular particles from all three cultures were detected by electron microscopy. Further research on the mechanisms of interspecies communication is needed to advance the understanding of microbial communities at the nano-level.