- Splitting droplets through coalescence of two different three-phase contact lines. [Journal Article]
- SMSoft Matter 2019 Jun 19
- Moving contact lines of more than two phases dictate a large number of interfacial phenomena. Despite their significance in fundamental and applied processes, the contact lines at a junction of four-…
Moving contact lines of more than two phases dictate a large number of interfacial phenomena. Despite their significance in fundamental and applied processes, the contact lines at a junction of four-phases (two immiscible liquids, a solid and gas) have been addressed only in a few investigations. Here, we report an intriguing phenomenon that follows after the four phases oil, water, solid and gas make contact through the coalescence of two different three-phase contact lines. We combine experimental studies and theoretical analyses to reveal and rationalize the dynamics exhibited upon the coalescence between the contact line of a micron-sized oil droplet and the receding contact line of a millimeter-sized water drop that covers the oil droplet on the substrate. We find that after the coalescence a four-phase contact line is formed for a brief period. However this quadruple contact line is not stable, leading to a 'droplet splitting' effect and eventually expulsion of the oil droplet from the water drop. We then show that the interfacial tension between the different phases and the viscosity of the oil droplet dictate the splitting dynamics. More viscous oils display higher resistance to the extreme deformations of the droplet induced by the instability of the quadruple contact line and no droplet expulsion is observed in such cases.
- Mst1 deletion reduces septic cardiomyopathy via activating Parkin-related mitophagy. [Journal Article]
- JCJ Cell Physiol 2019 Jun 18
- Cardiomyocyte function and viability are highly modulated by mammalian Ste20-like kinase 1 (Mst1)-Hippo pathway and mitochondria. Mitophagy, a kind of mitochondrial autophagy, is a protective program…
Cardiomyocyte function and viability are highly modulated by mammalian Ste20-like kinase 1 (Mst1)-Hippo pathway and mitochondria. Mitophagy, a kind of mitochondrial autophagy, is a protective program to attenuate mitochondrial damage. However, the relationship between Mst1 and mitophagy in septic cardiomyopathy has not been explored. In the present study, Mst1 knockout mice were used in a lipopolysaccharide (LPS)-induced septic cardiomyopathy model. Mitophagy activity was measured via immunofluorescence, Western blotting, and enzyme-linked immunosorbent assay. Pathway blocker and small interfering RNA were used to perform the loss-of-function assay. The results demonstrated that Mst1 was rapidly increased in response to LPS stress. Knockout of Mst1 attenuated LPS-mediated inflammation damage, reduced cardiomyocyte death, and improved cardiac function. At the molecular levels, LPS treatment activated mitochondrial damage, such as mitochondrial respiratory dysfunction, mitochondrial potential reduction, mitochondrial ATP depletion, and caspase family activation. Interestingly, in response to mitochondrial damage, Mst1 deletion activated mitophagy which attenuated LPS-mediated mitochondrial damage. However, inhibition of mitophagy via inhibiting parkin mitophagy abolished the protective influences of Mst1 deletion on mitochondrial homeostasis and cardiomyocyte viability. Overall, our results demonstrated that septic cardiomyopathy is linked to Mst1 upregulation which is followed by a drop in the protective mitophagy.
- Nephroprotective Effect of Herbal Extract Eurycoma longifolia on Paracetamol-Induced Nephrotoxicity in Rats. [Journal Article]
- EBEvid Based Complement Alternat Med 2019; 2019:4916519
- Paracetamol (PCM) is a well-known drug widely used for its analgesic and antipyretic properties. PCM is generally considered as safe but overdose of PCM can cause nephrotoxicity. Traditionally, herbs…
Paracetamol (PCM) is a well-known drug widely used for its analgesic and antipyretic properties. PCM is generally considered as safe but overdose of PCM can cause nephrotoxicity. Traditionally, herbs have been used for the treatment of drug or toxin-induced renal disorders and numerous medicinal plants were tested for nephroprotection effect in PCM-induced nephrotoxicity model. The aim of the present study was to evaluate the protective effect of the herbal extract Eurycoma longifolia (EL) against PCM-induced nephrotoxicity rat model. Forty Wistar rats were randomly divided into five groups of eight rats each: control (vehicle 10 ml/kg), PCM alone (200 mg/kg PCM), EL 100 (EL 100 mg/kg+200 mg/kg PCM), EL 200 (EL 200 mg/kg+200 mg/kg PCM), and EL 400 (EL 400 mg/kg+200 mg/kg PCM). All animals from control group received vehicle daily and animals from groups PCM alone, EL 100, EL 200, and EL 400 received repeated dose of PCM and the assigned treatment of EL daily for a period of 14 days. On the 15th day, serum creatinine, blood urea nitrogen, protein, and albumin were measured in blood and creatinine clearance was measured in urine collected over 24 hours. Kidney sections of all experimental groups underwent histopathological analysis. There was a significant (p<0.05) increase in serum creatinine and blood urea levels in the PCM alone group compared to the treatment groups due to nephrotoxicity. In the treatment groups, there was a dose-dependent protection against PCM-induced changes observed in serum total protein, albumin, urea, and creatinine. Significant (p<0.05) drop was seen in serum creatinine and blood urea content in EL 200 and EL 400 groups. Creatinine clearance significantly increased for EL 200 (p<0.01) and EL 400 (p < 0.001) groups. Serum total protein and serum albumin content were significantly increased (p<0.05) in EL 200 and EL 400 groups compared to PCM alone group. Histopathological examination (H&E staining) of the rat kidneys revealed severe degeneration in the PCM alone group, while there was evidence of significant dose-dependent protection in the treatment groups against PCM-induced changes. The serum and urine biochemical results and histopathology analysis of the kidney indicate the nephroprotective potential of EL extract against PCM-induced nephrotoxicity.
- Deoxynivalenol, but not fumonisin B1, aflatoxin B1 or diesel exhaust particles disrupt integrity of the horse's respiratory epithelium and predispose it for equine herpesvirus type 1 infection. [Journal Article]
- VMVet Microbiol 2019; 234:17-24
- The horse's respiratory tract daily encounters a plethora of respirable hazards including air pollutants, mycotoxins and airborne pathogens. To date, the precise effect of air pollution and mycotoxin…
The horse's respiratory tract daily encounters a plethora of respirable hazards including air pollutants, mycotoxins and airborne pathogens. To date, the precise effect of air pollution and mycotoxins on respiratory epithelial integrity and subsequent pathogen invasion in the horse has not been studied. Here, diesel exhaust particles (DEP) and three major mycotoxins (deoxynivalenol [DON], aflatoxin B1 [AFB1] and fumonisin B1 [FB1]) were applied to the apical surfaces of both ex vivo respiratory mucosal explants and in vitro primary equine respiratory epithelial cells (EREC) cultivated at the air-liquid interface, prior to inoculation with equine herpesvirus type 1 (EHV1). DON, but not AFB1, FB1 and DEP affected epithelial integrity in both ex vivo and in vitro systems, as demonstrated by histological changes in respiratory epithelial morphology and a drop in transepithelial electrical resistance across the EREC monolayer. Further, DON-pretreated explants showed on average 6.5 ± 4.5-fold more EHV1 plaques and produced on average 1 log10 more extracellular virus particles compared to control diluent- and FB1-pretreated respiratory mucosal explants. Similarly, EHV1 infection was greatly enhanced in EREC upon pretreatment with DON. Based on our findings, we propose that inhalation of DON predisposes horses for EHV1 infection by affecting respiratory epithelial integrity.
- A Differential Pressure Sensor Coupled with Conductance Sensors to Evaluate Pressure Drop Prediction Models of Gas-Water Two-Phase Flow in a Vertical Small Pipe. [Journal Article]
- SSensors (Basel) 2019 Jun 17; 19(12)
- In the process of production logging to evaluate fluid flow inside pipe, logging tools that force all flow to pass through a small measuring pipe are commonly utilized for measuring mixture density. …
In the process of production logging to evaluate fluid flow inside pipe, logging tools that force all flow to pass through a small measuring pipe are commonly utilized for measuring mixture density. For these logging tools, studying the fluid flow phenomenon inside the small diameter pipe and improving the prediction accuracy of pressure drop are beneficial to accurately measure mixture density. In this paper, a pressure drop prediction system is designed based on a combination of an eight-electrode rotating electric field conductance sensor (REFCS), plug-in cross-correlation conductance sensor, and differential pressure sensor. This combination overcomes the limitation of the existing pressure drop prediction model that the inlet flow velocity needs to be known. An experiment is conducted in a flow loop facility with 20 mm inner diameter small pipe. The responses of the combination sensors are collected. The REFCS is used to identify flow pattern and measure water holdup. During which five flow patterns are identified by recurrence plot method, i.e., slug flow, bubble flow, churn flow, bubble-slug transitional flow, and slug-churn transitional flow. The mixture velocity of two-phase flow is determined by the plug-in conductance sensor. The differential pressure sensor provides a differential pressure fluctuation signal. Five models of prediction of pressure drop are evaluated. The mixture friction factor of gas-water two-phase flow is obtained by a fitting method based on the measured parameters and flow pattern identification using the optimal model. Then, the pressure drop can be predicted according to the measurement results of a conductance sensor and fitting relationship. The results of pressure drop prediction show that the model proposed by Ansari et al. presents a higher accuracy compared with the other four differential pressure models with the absolute average percentage deviation (AAPD) of less than 2.632%. Moreover, the accuracy of pressure drop prediction of the Zhang et al. model is improved by using the mixture friction factor.
- A Combined Barite-Ilmenite Weighting Material to Prevent Barite Sag in Water-Based Drilling Fluid. [Journal Article]
- MMaterials (Basel) 2019 Jun 17; 12(12)
- Barite sag is a serious problem encountered while drilling high-pressure/high-temperature (HPHT) wells. It occurs when barite particles separate from the base fluid leading to variations in drilling …
Barite sag is a serious problem encountered while drilling high-pressure/high-temperature (HPHT) wells. It occurs when barite particles separate from the base fluid leading to variations in drilling fluid density that may cause a serious well control issue. However, it occurs in vertical and inclined wells under both static and dynamic conditions. This study introduces a combined barite-ilmenite weighting material to prevent the barite sag problem in water-based drilling fluid. Different drilling fluid samples were prepared by adding different percentages of ilmenite (25, 50, and 75 wt.% from the total weight of the weighting agent) to the base drilling fluid (barite-weighted). Sag tendency of the drilling fluid samples was evaluated under static and dynamic conditions to determine the optimum concentration of ilmenite which was required to prevent the sag issue. A static sag test was conducted under both vertical and inclined conditions. The effect of adding ilmenite to the drilling fluid was evaluated by measuring fluid density and pH at room temperature, and rheological properties at 120 °F and 250 °F. Moreover, a filtration test was performed at 250 °F to study the impact of adding ilmenite on the drilling fluid filtration performance and sealing properties of the formed filter cake. The results of this study showed that adding ilmenite to barite-weighted drilling fluid increased fluid density and slightly reduced the pH within the acceptable pH range (9-11). Ilmenite maintained the rheology of the drilling fluid with a minimal drop in rheological properties due to the HPHT conditions, while a significant drop was observed for the base fluid (without ilmenite). Adding ilmenite to the base drilling fluid significantly reduced sag factor and 50 wt.% ilmenite was adequate to prevent solids sag in both dynamic and static conditions with sag factors of 0.33 and 0.51, respectively. Moreover, HPHT filtration results showed that adding ilmenite had no impact on filtration performance of the drilling fluid. The findings of this study show that the combined barite-ilmenite weighting material can be a good solution to prevent solids sag issues in water-based fluids; thus, drilling HPHT wells with such fluids would be safe and effective.
- Investigation of Polyurethane Matrix Membranes for Salivary Nitrate ISFETs to Prevent the Drift. [Journal Article]
- SSensors (Basel) 2019 Jun 17; 19(12)
- We have investigated human-stress monitoring by making use of salivary nitrate, which can be a candidate for stress markers, with ion-selective field-effect transistors (ISFETs). ISFETs are suitable …
We have investigated human-stress monitoring by making use of salivary nitrate, which can be a candidate for stress markers, with ion-selective field-effect transistors (ISFETs). ISFETs are suitable for on-site single-drop analysis of salivary nitrate within 10 s. However, when ISFETs are used for salivary nitrate, ISFETs have a problem that is called the initial drift. The initial drift makes accurate nitrate monitoring difficult. Thus, the purpose of this study is to prevent the initial drift and to search for a new, simple polymer to possess a better performance of sensor responses than conventional matrix membranes, such as PVC. In this research, we investigated ISFETs using specific matrix membranes, for example KP-13, Pellethane®--, and P7281-PU. The initial drift was evaluated from the fluctuations of the response values generated by the ISFETs when immersed in saliva or aqueous solution. As a result, P7281-PU showed a prevention effect on the initial drift, both in the whole saliva and in various solutions. Furthermore, the cause of drift may be H+ diffusion, and the drift prevention effect of P7281-PU may be affected by urethane bond capturing H+ in the ion-selective membrane. This result suggests that a continuous nitrate monitoring is feasible and may be applied to wearable sensors.
- Modelling the Temperature Dependent Biaxial Response of Poly(ether-ether-ketone) Above and Below the Glass Transition for Thermoforming Applications. [Journal Article]
- PPolymers (Basel) 2019 Jun 12; 11(6)
- Desire to accurately predict the deformation behaviour throughout industrial forming processes, such as thermoforming and stretch blow moulding, has led to the development of mathematical models of m…
Desire to accurately predict the deformation behaviour throughout industrial forming processes, such as thermoforming and stretch blow moulding, has led to the development of mathematical models of material behaviour, with the ultimate aim of embedding into forming simulations enabling process and product optimization. Through the use of modern material characterisation techniques, biaxial data obtained at conditions comparable to the thermoforming process was used to calibrate the Buckley material model to the observed non-linear viscoelastic stress/strain behaviour. The material model was modified to account for the inherent anisotropy observed between the principal directions through the inclusion of a Holazapfel-Gasser-Ogden hyperelastic element. Variations in the post-yield drop in stress values associated with deformation rate and specimen temperature below the glass transition were observable, and facilitated in the modified model through time-temperature superposition creating a linear relationship capable of accurately modelling this change in yield stress behaviour. The modelling of the region of observed flow stress noted when above the glass transition temperature was also facilitated through adoption of the same principal. Comparison of the material model prediction was in excellent agreement with experiments at strain rates and temperatures of 1-16 s-1 and 130-155 °C respectively, for equal-biaxial mode of deformation. Temperature dependency of the material model was well replicated with across the broad temperature range in principal directions, at the reference strain rate of 1 s-1. When concerning larger rates of deformation, minimum and maximum average error levels of 6.20% and 10.77% were noted. The formulation, and appropriate characterization, of the modified Buckley material model allows for a stable basis in which future implementation into representative forming simulations of poly-aryl-ether-ketones, poly(ether-ether-ketone) (PEEK) and many other post-yield anisotropic polymers.
- Powerful harmonic charging in a quantum battery. [Journal Article]
- PRPhys Rev E 2019; 99(5-1):052106
- We consider a harmonic charging field as an energy charger for the quantum battery, which consists of an ensemble of two-level atoms. The charging of noninteracting atoms is completely fulfilled, whi…
We consider a harmonic charging field as an energy charger for the quantum battery, which consists of an ensemble of two-level atoms. The charging of noninteracting atoms is completely fulfilled, which exhibits a substantial improvement over previous static charging fields. Involving the repulsive interactions of atoms, the fully charging is achieved with shorter charged period over the noninteracting case, yielding an advantage for the charging. Excluding the charging field, a quantum phase transition is induced by the attractive atom-atom interactions, and the interacting atoms become degenerate in the ground state. We find that the degenerate states play a negative role in the charging due to the gapless energies. The atoms with strong attractive interactions can not be charged completely, which is accompanied by a drop of the maximum stored energy.
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- Survival of Herpes Simplex Virus Type 1 on Some Common Foods Routinely Touched before Consumption. [Journal Article]
- JFJ Food Prot 1997; 60(10):1259-1261
- Droplets of saliva containing herpes simplex virus type 1 were placed on the skin of tomatoes and the upper surface of lettuce leaves. There was no loss of virus infectivity titer at refrigerator tem…
Droplets of saliva containing herpes simplex virus type 1 were placed on the skin of tomatoes and the upper surface of lettuce leaves. There was no loss of virus infectivity titer at refrigerator temperature (2°C) at any time examined up to 1 h, the longest period tested. At room temperature (22 to 24°C) there was a 2-log drop in titer between 30 and 60 min, but some infectious virus was still present at 1 h. The virus-containing saliva remained in a liquid state at 2°C. At 22 to 24°C the droplets became dry at approximately 50 min. Implications of the findings are discussed.