Min Of Exposure Research Articles

Effect of combination of UV-A light and chitosan-gallic acid coating on microbial safety and quality of fresh strawberries

Strawberries can be contaminated by foodborne pathogens or mold on farm or during postharvest handling. Photo-irradiation of edible chitosan coating containing gallic acid can be an innovative antimicrobial intervention to improve the safety and shelf-life of strawberries. This study investigated antimicrobial activity of chitosan-gallic acid coating under 360 nm UV-A light. The thin layer of coating material allowed 80% of UV-A light transmission while blocking the majority of UV-C (200–280 nm) light. The formation of the coating layer was visualized by light and confocal microscopes. After 180 min exposure to UV-A, a 2.3 ± 0.4 log reduction of E. coli O157:H7 on chitosan-gallic acid (CH-GA) coated strawberries was achieved, which were significantly (P < 0.05) higher than CH, GA, and CH-GA without UV-A (average 0.3–1.0 log reductions) and UV-A. This level of inactivation was also significantly (P < 0.05) higher than GA + UV-A treatment (1.2 ± 0.4 log reductions), but not significantly different from (P > 0.05) CH + UV-A (1.8 ± 1.0 log reductions) treatment. The photo-irradiated coating did not significantly (P > 0.05) alter the mold decay incidence (%) in strawberries. Additionally, the redness and yellowness values of CH-GA + UV-A treated berries (35.4 ± 0.9, 22.0 ± 1.0) were initially lower (P < 0.05) than the control (40.5 ± 0.3, 26.1 ± 2.6), and became comparable (P > 0.05) after 14 days of storage. Comparatively, their firmness values did not show differences (P > 0.05) throughout the storage. Findings demonstrated the potential for using photo-irradiated coatings to reduce food safety risk in strawberries.

Rapid Method to Quantify the Antiviral Potential of Porous and Nonporous Material Using the Enveloped Bacteriophage Phi6.

The pandemic revealed significant gaps in our understanding of the antiviral potential of porous textiles used for personal protective equipment and nonporous touch surfaces. What is the fate of a microbe when it encounters an abiotic surface? How can we change the microenvironment of materials to improve antimicrobial properties? Filling these gaps requires increasing data generation throughput. A method to accomplish this leverages the use of the enveloped bacteriophage ϕ6, an adjustable spacing multichannel pipette, and the statistical design opportunities inherent in the ordered array of the 24-well culture plate format, resulting in a semi-automated small drop assay. For 100 mm2 nonporous coupons of Cu and Zn, the reduction in ϕ6 infectivity fits first-order kinetics, resulting in half-lives (T50) of 4.2 ± 0.1 and 29.4 ± 1.6 min, respectively. In contrast, exposure to stainless steel has no significant effect on infectivity. For porous textiles, differences associated with composition, color, and surface treatment of samples are detected within 5 min of exposure. Half-lives for differently dyed Zn-containing fabrics from commercially available masks ranged from 2.1 ± 0.05 to 9.4 ± 0.2 min. A path toward full automation and the application of machine learning techniques to guide combinatorial material engineering is presented.

Switching on Cytotoxicity of Water-Soluble Diiron Organometallics by UV Irradiation.

The diiron compounds [Fe2Cp2(CO)2(μ-CO)(μ-CSEt)]CF3SO3, [1]CF3SO3, K[Fe2Cp2(CO)3(CNCH2CO2)], K[2], [Fe2Cp2(CO)2(μ-CO)(μ-CNMe2)]NO3, [3]NO3, [Fe2Cp2(CO)2(PTA){μ-CNMe(Xyl)}]CF3SO3, [4]CF3SO3, and [Fe2Cp2(CO)(μ-CO){μ-η:1η3-C(4-C6H4CO2H)CHCNMe2}]CF3SO3, [5]CF3SO3, containing a bridging carbyne, isocyanoacetate, or vinyliminium ligand, were investigated for their photoinduced cytotoxicity. Specifically, the novel water-soluble compounds K[2], [3]NO3, and [4]CF3SO3 were synthesized and characterized by elemental analysis and IR and multinuclear NMR spectroscopy. Stereochemical aspects concerning [4]CF3SO3 were elucidated by 1H NOESY NMR and single-crystal X-ray diffraction. Cell proliferation studies on human skin cancer (A431) and nontumoral embryonic kidney (HEK293) cells, with and without a 10-min exposure to low-power UV light (350 nm), highlighted the performance of the aminocarbyne [3]NO3, nicknamed NIRAC (Nitrate-Iron-Aminocarbyne), which is substantially nontoxic in the dark but shows a marked photoinduced cytotoxicity. Spectroscopic (IR, UV-vis, NMR) measurements and the myoglobin assay indicated that the release of one carbon monoxide ligand represents the first step of the photoactivation process of NIRAC, followed by an extensive disassembly of the organometallic scaffold.

Spermatological characteristics and effects of cryopreservation in Lebranche mullet spermatozoa (Mugil liza Valenciennes, 1836): First report of ultra-rapid freezing

The present study investigated the spermatological characteristics of raw semen of Lebranche mullet (Mugil liza), namely pH, and sperm density, and motility; and subsequently evaluated the effects of different times of exposure to cryoprotectants, and the application of an ultra-rapid freezing protocol, on sperm motility and plasma membrane integrity. Semen samples were analyzed undiluted (control) and diluted 1:50 v/v in CF-HBSS + 10% Dimethyl sulfoxide + 30% Ethylene glycol + 94.58 gL−1 Trehalose dehydrate (n = 15). Two treatments – diluted semen samples in cryoprotective medium without ultra-rapid freezing (T1), and diluted semen in cryoprotective medium with ultra-rapid freezing (T2) – were evaluated at 0, 2, 4, 6 and 8 min. The frozen samples were thawed at 37ºC for 60 s. The spermatological characteristics recorded for the semen were: pH: 7.57 ± 0.21; sperm density: 30.4 ± 2.9 × 109 sperm mL−1; motility: 82 ± 4.9%. Sperm motility presented differences after 2 min exposure to cryoprotectants (70.0 ± 2.7%) and ultra-rapid freezing (66.5 ± 5.8%) compared to the control group (98.5 ± 1.9% and 98.5 ± 2.1%, respectively; p < 0.05). On the other hand, the plasma membrane integrity of the spermatozoa after 2 min exposure to cryoprotectants (64.0 ± 8.6%) and ultra-rapid freezing (62.5 ± 5.2%) presented no differences compared to the control group (69.5 ± 3.9% and 70.0 ± 3.5%, respectively p > 0.05); however, differences were observed in the parameters evaluated after longer exposure and cryopreservation times. This is the first report evaluating the effects of different times of exposure to cryoprotectants and direct ultra-rapid freezing in liquid nitrogen on Mugil liza sperm. Our results demonstrated the protocol of sperm ultra-freezing is safe within a time´s window of 2 min of exposure to cryoprotectants, after which a toxicity effect on sperm can be observed.

Optimising the photothrombotic model of stroke in the C57BI/6 and FVB/N strains of mouse

The photothrombotic stroke model relies on the interaction between photosensitive-dye and light for clot formation. Interestingly, the relationship between the length of light exposure and stroke-outcome has never been examined. This model has yet to be established in the FVB/N strain, even though stroke-outcomes are strain-specific. Therefore, this study aimed to examine the effect of different lengths of light exposure in two strains of mice on photothrombotic stroke. Male FVB/N and C57Bl/6 mice were subjected to stroke using 15, 18, or 20-min light exposure. Mice underwent functional testing for up to 7 days. Infarct volume was assessed with thionin staining, and cellular responses to injury analysed via immunofluorescence at 7-days post-stroke. Blood brain barrier (BBB) breakdown was assessed using Evans blue dye at 4.5-h post-stroke. Increasing light exposure from 15 to 20-min increased infarct volume but not functional deficit. Interestingly, there were strain-specific differences in functional outcomes, with FVB/N mice having less deficit on the hanging wire test than C57BI/6 after 15-min of light exposure. The opposite was seen in the adhesive removal test. There was no difference in the number of neurons, astrocytes, microglia, macrophages, and T cells between the strains, despite FVB/N mice demonstrating greater BBB breakdown and an enlarged spleen post-stroke. Increasing light exposure systematically increases infarct volume but does not worsen functional outcomes. FVB/N and C57Bl/6 mice exhibit subtle differences in functional outcomes post stroke, which highlights the need to choose tests which are appropriate for the mouse strain being used.

Moisture Stability of Sulfide Solid-State Electrolytes

In this report we detail a comprehensive study on the moisture stability of sulfide solid-state electrolytes in dry room environments. Although sulfide SSEs have many favorable attributes, this class of materials suffers from poor stability with water. Sulfide SSEs react with water to form gaseous H2S and a variety of solid byproducts like Li3PO4 and LiOH, which go on to increase the interfacial impedance of solid-state batteries. Lab-scale research typically utilizes gloveboxes with &amp;lt;1 ppm water, however, the large-scale manufacturing of Li-ion batteries occurs in −40°C dewpoint dry rooms with around 126 ppm water. Consequently, the moisture stability of sulfide SSEs must be addressed if the manufacture of solid-state batteries based on sulfide SSEs is to be scaled up. Here, we are the first to characterize the moisture stability of sulfide SSEs according to both H2S and the degradation of ionic conductivity at different moisture setpoints ranging from −76°C to −40°C dewpoint. A variety of different SSE compositions are studied; namely, (Li2S)75(P2S5)25, (Li2S)70(P2S5)30, (Li2O)7(Li2S)68(P2S5)25, (Li2O)7(Li2S)63(P2S5)30, and (Li2S)75(P2S5)25 + 20 mol% LiI. We find that moisture stability improves with 75 mol% Li2S modifier content and the introduction of a Li2O co-modifier. After a 30 min exposure in a −40°C dewpoint dry room environment we found that (Li2S)75(P2S5)25 + 20 mol% LiI powder generated 0.1 cc/g H2S and its ionic conductivity decreased by over 50%. However, when SSE powder was exposed as a slurry in a dodecane carrier the same SSE composition generated 0 cc/g H2S and its ionic conductivity only dropped by 14%. Our results show that sulfide SSEs have acceptable moisture stability when appropriately processed in a dry room environment.

In Vitro Corneal and Conjunctival Wound-Healing Assays as a Tool for Antiglaucoma Prostaglandin Formulation Characterization.

Benzalkonium chloride (BAK)-containing antiglaucoma therapies alter the ocular surface over the long term. We used an in vitro scraping model to compare the effects of preserved and unpreserved topical commercial prostaglandins (PGs) in a wound-healing model. Standardized mechanical scraping was performed in confluent immortalized human corneal/conjunctival epithelial cell layers. Cytotoxicity, cell migration and proliferation, as well as the percentage of closure, were analyzed 2 h and 1/2/3/6 days after a 30-min exposure to 1/10 dilutions in phosphate buffered saline (PBS) used also as control, BAK solutions at concentrations ranging from 0.0001% to 0.1%, latanoprost-0.02%BAK, travoprost-0.015%BAK, bimatoprost-0.005%BAK, BAK-free Tafluprost, latanoprost in cationic emulsion, and travoprost (Polyquad® and SofZia®). PG eyedrop preparations with BAK preservative delayed corneal healing, which is primarily related to the presence of BAK, in a dose-dependent manner, especially at day 1, as evidenced through actin disorganization and decreased Ki-67-positive cell numbers. The PGs (BAK-free tafluprost, latanoprost in cationic emulsion,travoprost (Polyquad® and SofZia®)) maintained a normal healing process with results similar to those of control. Conjunctiva-derived cell layers healed more slowly than corneal cell layers and were more sensitive in in vitro cytotoxicity tests. This novel in vitro scraping model mimics the damaged ocular surface epithelia observed in glaucoma patients affected by ocular surface disease, such as toxic-induced dry eye (TIDE) and offers a tool to assess the potential cytotoxic effects of PG formulations with or without BAK.

Fabrication of a holographic mask with high consistency for convex blazed grating

This study aimed to fabricate a holographic mask that can be developed to the bottom of the whole convex substrate and has the same groove depth, to meet the requirements of ion beam etching. The influence of light fields and exposure parameters on different positions of the photoresist substrate surface was studied. By comparing and analyzing the groove of holographic masks fabricated with different conditions, a holographic convex grating mask with high groove consistency can be obtained under the conditions of 40× light spot and 18 min exposure time. Finally, the high quality of the optimized holographic was verified by tests with ion beam etching.

Single Prolonged Stress Alters Vasopressin and Orexin System Expression in Sprague Dawley Rats

Posttraumatic stress disorder (PTSD) is a complex psychiatric disorder triggered by a terrifying event, causing severe anxiety and nightmares. Studies showed that patients with PTSD have increased risk of cardiovascular disease. However, the effect of PTSD on blood pressure remains unraveled. In this study, we test the hypothesis that PTSD alters expression of arginine vasopressin (AVP) and orexin system components and therefore increases blood pressure. Single prolonged stress (SPS) protocol including 2 hours of restraint, a 20‐min forced swimming and exposure to diethyl ether until loss of consciousness was used to create a PTSD model. Eight‐week‐old male Sprague Dawley (SD) rats were divided into two groups and treated with or without SPS, then all rats were single‐housed and remained undisturbed for 7 days. Their blood pressure (BP) and heart rates (HR) were recorded by radio telemetry transmitter system (Data Science International) prior to the treatment as baseline, and 1‐ day, and 7‐day post the treatment. The data showed that SPS significantly increased BP (ΔBP: 8.384 ± 1.187 mmHg, N=6 P&lt;0.05) and HR (ΔHR: 32.88 ± 9.149 beats/min, N=6 P&lt;0.05) compared to control rats (ΔBP: 2.346 ± 0.9324 mmHg, ΔHR: ‐1.503 ± 5.960 beats/min, N=8) on day 1 post treatment, but no significance difference was observed in BP and HR on day 7 compared to their own baseline and between SPS and control groups.To investigate whether AVP and orexin systems participate in PTSD development, we examined paraventricular nucleus (PVN) and adrenal gland AVP‐ and orexin receptor 1 (OX1R) and orexin receptor 2 (OX2R) expression in both SD male and female rats with or without SPS at day 7. Our data showed that PVN AVP mRNA levels were increased by 2‐fold in the SPS group compared to control in male rats (P&lt;0.05) but this change was not observed in female rats. No changes were observed in PVN OX1R and OX2R mRNA levels between SPS and control rats in both males and females. Peripheral orexin receptors’ protein levels were altered but showed inconsistency in male and female rats: western blot data showed that adrenal gland OX1R protein levels were increased in the SPS group (control: 1.000 ± 0.07424 N=5 vs SPS: 1.531 ± 0.2016 N=5; P&lt;0.05) in male rats, while OX2R protein levels were decreased in female rats in female rats (control: 1.000 ± 0.01025 N=5 vs SPS: 0.8840 ± 0.04533 N=6; P&lt;0.05). Renal OX1R was also increased (control: 1.000 ± 0.02794 N=3 vs SPS: 1.374 ± 0.1385 N=3; P&lt;0.06) in female rats under SPS. ELISA assay showed that plasma orexin A levels were increased in female rats under SPS (control: 1.000 ± 0.1600 pg/mL N=3 vs SPS: 1.561 ± 0.1262 pg/mL; N=3 P&lt;0.05) but not in male rats.These results suggested that the central AVP system and peripheral orexin system may play a role in PTSD‐related high blood pressure development, and the peripheral orexin system may mediate stress response of female rats more than male rats. These molecular differences between SD male and female rats may also help to answer why females and males showed different responses to trauma. Further study will continue to find the PTSD‐sensitized hypertensive model and investigate specific functions of AVP and orexin system in PTSD.

Identifying the vagal bronchopulmonary afferents responsible for eliciting the cough response to inhaled sulfur dioxide in mice

Among the three major types of vagal sensory nerves innervating the lung and airways, C‐fibers and rapidly adapting receptors (RARs or irritant receptors) are known to possess the properties and functions of “cough receptors”, but their relative roles in regulating cough reflex responses to inhaled irritants are not yet clearly defined. To address this question, we have recently carried out a series of studies in a mouse cough model, in which the intra‐pleural pressure was continuously recorded by a surgically implanted telemetry sensor. Sulfur dioxide (SO2), a common irritant gas, was chosen for the study because its widespread use as a chemical agent in various industrial operations has led to severe lung injuries in workers in numerous incidences resulting from accidental release of high concentrations of SO2 in industrial facilities. Inhalation of SO2 (300 and 600 ppm) consistently and reproducibly elicited coughs in a concentration‐dependent manner in awake mice moving freely in a recording chamber. The cough frequency increased rapidly after the onset of the SO2 inhalation challenge, which continued for the remaining duration of 8‐min exposure. In the current study, single‐fiber electrophysiological recording of vagal afferent activity in anesthetized mice showed that the high concentration of SO2 (600 ppm) evoked a sustained stimulatory effect on C‐fibers for the entire duration (8 min) of the inhalation challenge. However, in sharp contrast, inhalation of SO2 at the same concentration and duration generated a distinct and consistent inhibitory effect on both phasic RARs and slowly adapting receptors. Their respiratory cycle‐related phasic discharge declined progressively and/or ceased completely within 1‐3 min after the onset of the SO2 inhalation challenge, which gradually recovered after &gt;15 min following the termination of the SO2 inhalation. In a small percentage of RARs that displayed no phasic activity during eupneic breathing and often exhibited sensitivity to certain inhaled irritants, the same SO2 inhalation challenge did not evoke any significant stimulatory effect. Taken together, these observations suggest that stimulation of bronchopulmonary C‐fibers is primarily responsible for triggering airway irritation and coughing in response to the SO2 inhalation challenge.

Cardiomyocyte‐specific deletion of sarcoglycan‐δ leads to dilated cardiomyopathy, autonomic dysfunction, and exaggerated stress‐induced cardiovascular reactivity

Deficiency of sarcoglycan‐δ (Sgcd) induces disruption of the dystrophin glycoprotein complex, resulting in loss of membrane stability. We have reported that angiotensin II (AngII)‐mediated autonomic dysfunction precedes and predicts development of dilated cardiomyopathy (DCM) in the global Sgcd‐deficient mice [Exp Physiol 2015].The relative contribution of cardiomyocyte‐targeted Sgcd on DCM and autonomic dysfunction remains unknown. Our goal is to determine whether cardiac remodeling in the Sgcd mutations is an intrinsic process of the cardiomyocytes. We have also observed that global Sgcd‐deficient mice with DCM exhibit anxiety‐like behaviors. AngII via type 1 receptors (AT1R) is well‐known to mediate anxiety‐related behaviors, while Ang‐(1‐7) via Mas receptors is anxiolytic. Thus, we hypothesize that Sgcd in the ventricular myocytes is essential for the progression of DCM, and to elicit emotional stress responses. Cardiac‐specific Sgcd‐deficient (cSgcd‐KO) and littermate control (WT) mice were generated by breeding male αMHCcre+(αmyosin‐heavy chain Myh6 promoter drives expression of the cre‐recombinase) withfemaleglobal Sgcd‐deficientmice. Absence of Sgcdin the cardiomyocytes was confirmed by immunohistochemistry and qPCR in the cSgcd‐KO mice. WT (n=11) and cSgcd‐KO (n=14) mice were echoed every month, from 8 weeks of age, to monitor progression of DCM. At ~35 weeks of age, telemeters (DSI) were implanted to measure changes in blood pressure (BP), heart rate (HR) and locomotor activity during acute emotional stress challenge (20 min exposure to predator odor). Autonomic indices including baroreflex sensitivity (BRS, sequence technique), and resting cardiac vagal and sympathetic tone (HR responses to atropine and propranolol, respectively) were calculated. At 36±1 weeks of age, cSgcd‐KO mice exhibit 62% increase in left ventricular (LV) end‐diastolic volume, 58% decrease in LV ejection fraction, and increased cardiac fibrosis (p&lt;0.05 vs. 10 weeks of age). At baseline, cSgcd‐KO mice exhibit lower BP (100±6 vs.121±1 mmHg), reduced BRS (0.72±0.08 vs.2.01±0.05 ms/mmHg) and vagal tone (∆HR= +32±6 vs. +151±18 bpm), and increased sympathetic tone (∆HR= ‐212±12 vs. ‐123±10 bpm) (p&lt;0.05 vs.WT). Paradoxically, given increased basal sympathetic tone and decreased basal vagal tone, stress caused hypotension in the cSgcd‐KO mice with DCM, likely due to reduced cardiac output. This is accompanied by profound increase in AT1R, and reduced expression of Mas and MrgD receptors (ligand for newly identified heptapeptide alamandine) in LV and brainstem (p&lt;0.0001‐0.01 vs. baseline and WT). We conclude ‐ (i) Sgcddeleted exclusively from the cardiac myocytes creates a novel transgenic mouse strain that develops DCM at ~35 weeks of age. (ii) Stress‐evoked profound changes in CNS and systemic hemodynamics occur directly or indirectly, and cannot be ascribed to Sgcd loss in vascular smooth muscle, endothelium, neurons, or astrocytes. (iii) Contributions of the renin‐angiotensin system is pivotal in pathophysiology of Sgcd deficiencies.

Neurosteroid Role in the Integration of Olfactory Immune Responses in Rainbow Trout (Oncorhynchus Mykiss)

The objective of this study is to unravel the integration of olfactory signals involved in the nasal detection of pathogens and the activation of associated physiological responses in Rainbow trout.The infectious pathogen Yersinia ruckeri causes enteric redmouth disease in aquaculture farms worldwide. Recent research shows that olfactory organ of rainbow trout is highly susceptible external tissue like gills or skin due to direct contact with the microbiome‐rich environment. Recent findings have demonstrated that olfactory sensory cells play a key role in early pathogen detection and immune cell activation along with their primary role in detecting environmental stimuli.We hypothesize that olfactory immune responses elicited by Y ruckeri are modulated by neurosteroids. To test our hypothesis, we nasally exposed rainbow trout to Y. ruckeri vaccine or saline and took nose and brain samples at four different time periods (4 hours, 24 hours, 7 days, and 14 days) after exposure. We analyzed fish neurosteroids (cortisol, estradiol, and progesterone) and gene expression of steroidogenic enzymes (p450, 3β HSD, 11β HSD, and 17 β HSD) in nose, olfactory bulb, and rest of the brain. Exposure to Y. rukeri vaccine caused significant changes in tissue neurosteroid production and steroidogenic enzyme expression at different times after exposure.Within the olfactory epithelium (OE), we detected a significant decrease (p = 0.003) in estradiol after 15 min exposure with 26.1 pg/mg tissue and 391.0 pg/mg tissue in treated and control individual respectively. Progesterone (174.83 pg/mg tissue) was significantly (p = 0.004) higher after 4 hours compared to the control (26.5 pg/mg of tissue) and cortisol (10.95 pg/mg of tissue) was significantly lower (p = 0.003) after 14 days in Y. ruckeri‐treated fish compared to the control (78.76 pg/mg of tissue). Within the olfactory bulb (OB), lower concentrations of cortisol and progesterone (5.65 pg/mg tissue and 1.6 pg/mg tissue respectively) were observed after 15 minutes in the Y. ruckeri‐treated fish compared to the control (22.8 pg/mg of tissue and 1.9 pg/mg of tissue, respectively). There was also a higher concentration of estradiol after 15 minutes and 4 hours compared to the control. Lastly, within the rest of brain cortisol (9.1 pg/mg tissue) was significantly higher after 4 hours in vaccine treated fish compared to the control (4.9 pg/mg tissue) and estradiol was significantly lower after 15 minutes in the vaccine group (5.5 pg/mg of tissue), compared to the control (55.9 pg/mg of tissue). However, neurosteroid concentration in the rest of brain was relatively low compared to the OE and OB. The neurosteroids: cortisol, estradiol, and progesterone play many important roles in fish physiology including stress response, cognitive behavioral modulation, and immunological response. Our preliminary results also show a significant differential expression of steroidogenic enzymes after exposure to the vaccine. Altogether, our results demonstrate that neurosteroids play a critical role in the integration of immune olfactory responses in vertebrates.

Novel SARS‐CoV‐2 Inactivation Formulation Supports Extended COVID‐19 Testing/Surveillance

BackgroundWith the spread of highly infectious strains such as the Delta variant of SARS‐CoV‐2, rapid antigen testing and variant tracking are gaining more attention from infectious disease specialists and the general public as essentials for disease control and prevention amidst the COVID‐19 pandemic. The lateral flow based antigen tests provide fast turnaround of results within minutes, but it’s open ‐faced assay format means that the test operators are more prone to accidental exposure to pathogen‐containing samples. The viral inactivation transport media (ITMs) provide much needed protection against exposure to highly transmissive live viruses during sample collection, transport, and storage. However, the current ITMs were designed for PCR tests and share a harsh chemical formulation that denatures protein analytes, making them incompatible with antigen tests.We developed an innovative viral transport media that is designed for a variety of tests, such as antigen testing and PCR. The new formulation can be used to safely inactivate SARS‐CoV‐2 virus while maintaining compatibility with many different formats beyond rt‐PCR.DesignTo evaluate the viral inactivation performance of the novel inactivation transport media formulation, a cytopathic effect assay was conducted using VERO E6 cells in presence of SARS‐CoV‐2 samples incubated in our novel formulation and log reduction were reported.To assess its compatibility with different SARS‐CoV‐2 related assays, the novel formulation was used as inactivation transport media in antigen, PCR, and NGS based Swab‐Seq tests with known controls.ResultsThe results for the inactivation study confirmed > 3.0 log reduction in viral titer after 30 min exposure in novel transport media formulation and demonstrated 99.5% effectiveness in SARS‐CoV‐2 inactivation. The results for the PCR and antigen test compatibility studies showed comparable and/or superior performance in detection limits for the novel formulation when compared to other sample media. The Swab‐Seq result offers preliminary support on the novel formulation’s compatibility with NGS based assays.ConclusionUsing a novel viral transport medium, we were able to completely inactivate the SARS‐CoV‐2 virus. The new formulation was compatible with both nucleic acid and protein assays while protecting cells from infection. This viral transport media could allow more test types to be done from a single specimen, resulting in safer and reliable outcomes. Additionally, it would reduce the need for multiple samples collected from patients while supporting SARS‐CoV‐2 variant tracking via NGS.

Surface activity of biomolecules released from microalgae harvested by ozone-flotation

This paper evaluates the relation between the efficiency of harvesting microalgae biomass or biomolecules (proteins, lipids and carbohydrates) and the surface activity of the amphiphiles released during the harvesting process. Microalgae cultivated in wastewater was evaluated using a laboratory scale ozone-flotation reactor. Applying the highest biomass concentration (1800 mg/L) and a flow ratio gas–liquid of 3, recovered 79% biomass with a maximum yield of 7.6 mg biomass/mg O 3 and a release of biomolecules greater than 70%. Adjusting surface pressures of the harvested samples to integrated Gibbs model indicated that longer ozone than 19 min exposure times caused a decrease in the hydrophobic region of the molecules. This affected the efficiency of the amphiphiles present in the sample, requiring a higher concentration (from 534.72 ± 9.63 mg/L to 1542.45 ± 5.66 mg/L) to reduce the surface tension to the minimum values obtained (45.26 ± 0.73 mN/m). In conclusion, ozone exposure needs be closely monitored to ensure effective biomass and biomolecules separation. • Harvesting of biomass and biomolecules by ozone-flotation was higher than 70%. • Integrated Gibbs model described changes in microalgae’s amphiphiles. • Longer exposure to ozone caused a decrease in biomolecules’ hydrophobic region. • Ozone exposition must be controlled to ensure separation of biomolecules.

Ovocidal action of disinfectants against eggs of Passalurus ambiguus

Successful elimination of helminthic diseases, as well as their further prevention, is possible only under the condition of carrying out a complex of organizational and economic, veterinary and sanitary, and special anti-parasitic measures, which must necessarily include disinfestation of places where animals are kept, as well as environmental objects. It is necessary to establish the ability of modern chemical agents to harm certain types of parasites. The research aimed to determine the ovocidal efficiency of disinfectants in different concentrations and exposures against Passalurus ambiguus eggs isolated from domestic rabbits. An experimental test was carried out in laboratory conditions on chemical products of domestic production “Virosan”. (AS – alkyldimethylbenzylammonium chloride, glutaraldehyde) and “Hermecid-VS” (AS – didecyldimethylammonium chloride, glutaraldehyde, benzalkonium chloride). The leading indicator of the effect of disinfectants on the eggs of pasaluris was the value of their disinfestation efficiency. The results of the conducted studies established a high level of ovocidal efficiency of “Virosan” (OE – 100 %) against P. ambiguus eggs at 0.25 % concentration for exposures of 30–60 minutes and 0.5 % concentration for exposures of 10–60 minutes. A satisfactory level of the ovocidal efficiency of “Virosan” was established when using the agent in 0.1 % (30–60 min exposure) and 0.25 % (10 min exposure) concentrations, OE ranges from 62.36 to 82.20 %. An unsatisfactory level of the ovocidal efficiency of “Virosan” was established at 0.1 % of the concentration after exposure for 10 minutes (AS – 47.30 %). Disinfectant “Hermecid-VS” showed a high level of ovocidal efficiency concerning the eggs of pasaluris in 0.1 % concentration for 60 min exposure (OE – 91.45 %) and in 0.25–0.5 % concentration for 10–60 min exposure (AS – 100 %). A satisfactory ovocidal efficiency of “Hermecid-VS” was established when using the product at a concentration of 0.1 % (10 and 30-minute exposures), where OE indicators were 76.25 and 81.91 %, respectively. The obtained data make it possible to recommend disinfectants of domestic production “Virosan” and “Hermecid-VS” in specified concentrations and exposures to control and prevent pasalurosis in rabbits in order to effectively carry out the deinvasion of environmental objects and places where animals are kept.

Influence of an Acute Exposure to a Moderate Real Altitude on Motoneuron Pool Excitability and Jumping Performance.

The aim of the study was to test whether ascending to a moderate real altitude affects motoneuron pool excitability at rest, as expressed by a change in the H-reflex amplitude, and also to elucidate whether a possible alteration in the motoneuron pool excitability could be reflected in the execution of lower-body concentric explosive (squat jump; SJ) and fast eccentric-concentric (drop jump; DJ) muscle actions. Fifteen participants performed four experimental sessions that consisted of the combination of two real altitude conditions [low altitude (low altitude, 690 m), high altitude (higher altitude, 2,320 m)] and two testing procedures (H-reflex and vertical jumps). Participants were tested on each testing day at 8, 11, 14 and 17 h. The only significant difference (p < 0.05) detected for the H-reflex was the higher H-reflex response (25.6%) obtained 15 min after arrival at altitude compared to baseline measurement. In terms of motor behavior, DJ height was the only variable that showed a significant interaction between altitude conditions (LA and HA) and time of measurement (8, 11, 14 and 17 h) as DJ height increased more during successive measurements at HA compared to LA. The only significant difference between the LA and HA conditions was observed for DJ height at 17 h which was higher for the HA condition (p = 0.04, ES = 0.41). Although an increased H-reflex response was detected after a brief (15–20 min) exposure to real altitude, the effect on motorneuron pool excitability could not be confirmed since no significant changes in the H-reflex were detected when comparing LA and HA. On the other hand, the positive effect of altitude on DJ performance was accentuated after 6 h of exposure.

Solid particle erosion, water absorption and thickness swelling behavior of intra ply Kevlar/PALF fiber epoxy hybrid composites

AbstractIn this investigation, the different weaving pattern of intra ply Kevlar and pineapple leaf fiber (PALF) reinforced with epoxy hybrid composites was fabricated using the compression molding method. Solid particle erosion wear properties, water absorption, and thickness swelling behavior were tested. Solid particle erosion wear properties were tested using an air‐jet erosion tester. The various factors for solid particle erosion test were taken as impingement angle, exposure time, and weaving pattern. The weaving pattern was varied as plain type, twill type, basket type. The result showed that basket weave type and pure Kevlar fiber reinforced epoxy composites have better water absorption and thickness swelling properties. The results from the solid particle erosion test indicated that twill type and pure Kevlar fiber reinforced epoxy composites showed superior erosion wear resistance compared to other composites. Further, the statistical analysis was carried out using Taguchi analysis and their results showed that twill type Kevlar/PALF reinforced with epoxy composite was a minimum erosion wear rate at 90° of impingement angle and 6 min exposure time. The erosion mechanism of the surface eroded composite specimens was investigated using scanning electron microscopy.

Novel aerosol treatment of airway hyper-reactivity and inflammation in a murine model of asthma with a soluble epoxide hydrolase inhibitor.

Asthma currently affects more than 339 million people worldwide. In the present preliminary study, we examined the efficacy of a new, inhalable soluble epoxide hydrolase inhibitor (sEHI), 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU), to attenuate airway inflammation, mucin secretion, and hyper-responsiveness (AHR) in an ovalbumin (OVA)-sensitized murine model. Male BALB/c mice were divided into phosphate-buffered saline (PBS), OVA, and OVA+TPPU (2- or 6-h) exposure groups. On days 0 and 14, the mice were administered PBS or sensitized to OVA in PBS. From days 26-38, seven challenge exposures were performed with 30 min inhalation of filtered air or OVA alone. In the OVA+TPPU groups, a 2- or 6-h TPPU inhalation preceded each 30-min OVA exposure. On day 39, pulmonary function tests (PFTs) were performed, and biological samples were collected. Lung tissues were used to semi-quantitatively evaluate the severity of inflammation and airway constriction and the volume of stored intracellular mucosubstances. Bronchoalveolar lavage (BAL) and blood samples were used to analyze regulatory lipid mediator profiles. Significantly (p < 0.05) attenuated alveolar, bronchiolar, and pleural inflammation; airway resistance and constriction; mucosubstance volume; and inflammatory lipid mediator levels were observed with OVA+TPPU relative to OVA alone. Cumulative findings indicated TPPU inhalation effectively inhibited inflammation, suppressed AHR, and prevented mucosubstance accumulation in the murine asthmatic model. Future studies should determine the pharmacokinetics (i.e., absorption, distribution, metabolism, and excretion) and pharmacodynamics (i.e., concentration/dose responses) of inhaled TPPU to explore its potential as an asthma-preventative or -rescue treatment.

Short-Term Biodegradation of Crude Petroleum Oil in Water by Photostimulated Janibacter terrae Strain S1N1.

Biodegradation is a sustainable green strategy that gives the opportunity for remediation of water contaminated with petroleum products. In this study, 12 bacterial isolates were recovered from River Nile, Egypt and screened for their potential to degrade a mixture of paraffinic petroleum crude oil. The most promising isolate was identified according to 16S rRNA sequencing as Janibacter terrae strain S1N1 (GenBank accession No. KX570955.1). In order to boost the biodegradation efficiency, the bacterial suspension was photostimulated by exposure to different irradiation doses using a low-power helium–neon (He–Ne) laser (λ = 632.8 nm). Maximum biodegradation was achieved after 4 min of exposure (134.07 J cm–2) at optimized pH value (6) and temperature (35 °C). The gas chromatography–mass spectrometry (GC-MS) analysis revealed the biodegradation of 96.5% of the substrate after only 48 h of incubation. The n-C17/Pr and n-C18/Ph ratios indicated a preferential biodegradation of iso-paraffines over normal ones. Meanwhile, pristane/phytane (Pr/Ph) ratios were indicative of selective biodegradation for pristane. The carbon preference index (CPI) was nearly around unity indicating the ability of Janibacter terrae to attack the odd and even n-alkanes simultaneously. These results support the superiority of irradiated bacteria in optimizing the biodegradation efficiency and shortening the time of treatment, thus proposing an eco-friendly technique in water bioremediation programs.

UV inactivation of Semliki Forest virus andE. colibacteria by alternative light sources

The quick spreading of the SARS-CoV-2 virus, initiating the global pandemic with a significant impact on economics and health, highlighted an urgent need for effective and sustainable restriction mechanisms of pathogenic microorganisms. UV-C radiation, causing inactivation of many viruses and bacteria, is one of the tools for disinfection of different surfaces, liquids, and air; however, mainly mercury 254 nm line is commonly used for it. In this paper, we report our results of the experiments with newly elaborated special type polychromatic non-mercury UV light sources, having spectral lines in the spectral region from 190 nm to 280 nm. Inactivation tests were performed with both Escherichia coli (E.coli) bacteria and Semliki Forest virus (SFV) as a representative of human enveloped RNA viruses. In addition, the effect of prepared lamps on virus samples in liquid and dry form (dried virus-containing solution) was tested. Reduction of 4 log10 of E.coli was obtained after 10 min of irradiation with both thallium-antimony and arsenic high-frequency electrodeless lamps. High reduction results for the arsenic light source demonstrated sensitivity of E. coli to wavelengths below 230 nm, including spectral lines around 200 nm. For the Semliki Forest virus, the thallium-antimony light source showed virus inactivation efficiency with a high virus reduction rate in the range of 3.10 to > 4.99 log10 within 5 min of exposure. Thus, the new thallium-antimony light source showed the most promising disinfection effect in bacteria and viruses, and arsenic light sources for bacteria inactivation, opening doors for many applications in disinfection systems, including for pathogenic human RNA viruses.