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711.
Background: Infiltrations from cannulation result in significant morbidity including loss of hemodialysis (HD) vascular access (VA). Cannulation is dependent on personnel skill and VA characteristics. Surface marking of VA lacks real‐time information and traditional ultrasound (US) devices are large, expensive, requiring skilled operators. Sonic Window© (Analogic Ultrasound, Peabody, MA, USA) is a coronal mode ultrasound device (CMUD) approved for VA cannulation. Methods: Single center randomized, prospective pilot study comparing handheld US‐guided cannulation of new arteriovenous fistula (AVF) to standard cannulation practices. Patients with end stage renal disease (ESRD) on in‐center HD who had a new AVF cleared for cannulation and dialysis were enrolled. Patients with new AVF received either standard cannulation (control group) or image guidance using CMUD (study group) for 3 weeks. Ultrasound characteristics of VA, cannulation practices and complications end points were obtained. Results: An infiltration rate of 9.7% was noted during the study. Slightly lower odds ratio (OR) of infiltration was observed in the study group (OR 0.94, 95% CI: 0.26–3.41, P value = 0.93). Study group yielded longer time for assessment (101.8 ± 80.2 vs. 22.3 ± 22.5 seconds, P = < 0.001), increased cannulation time (41.1 ± 70.6 vs. 25.0 ± 27.9 seconds, P = 0.04), and increased patient satisfaction (94.6% vs. 82%, P = 0.04) compared to control group. Number of cannulation attempts, needle size, arterial or venous needle insertion, and tourniquet usage between groups were not statistically different. Conclusion: Handheld ultrasound is a safe and useful aid in cannulation of dialysis access.  相似文献   
712.
Silver nanoparticles (Ag NPs) were synthesised using the crude ethyl acetate extracts of Ulva lactuca and evaluated their bioefficacy against two crop‐damaging pathogens. The sets of lattice planes in the XRD spectrum for the Ag NPs were indexed to the 111, 200, 220 and 311 orientations and support the crystalline nature of the Ag NPs. The 3414 and 2968 cm−1 peaks were observed in crude algal thallus extract and they were characteristic of terpenoids. Further, a peak at 1389 cm−1 was observed as fatty acids. The marine macroalgae terpenoids and palmitic acid acted as reducing agent and stabiliser, respectively. The size (3 and 50 nm) and shape (spherical) of Ag NPs were recorded. The energy‐dispersive X‐ray spectroscopy analysis exemplified the presence of silver in its elemental nature. Moreover, U. lactuca Ag NPs were effective against two cotton phytopathogens namely Fusarium oxysporum f.sp. vasinfectum (FOV) and Xanthomonas campestris pv. malvacearum (XAM). The minimum inhibitory concentration was found to be 80.0 and 43.33 μg ml−1 against FOV and XAM, respectively. Results confirmed the anti‐microbial activity of green nanoparticles against select pathogens and suggest their possible usage in developing antifungal agents for controlling destructive pathogens in a cotton agroecosystem.Inspec keywords: nanoparticles, biotechnology, antibacterial activity, silver, microorganisms, X‐ray chemical analysis, crops, X‐ray diffraction, cottonOther keywords: crude ethyl acetate extracts, crop‐damaging pathogens, lattice planes, XRD spectrum, crystalline nature, crude algal thallus, fatty acids, marine macroalgae terpenoids, palmitic acid, energy‐dispersive X‐ray spectroscopy analysis, elemental nature, cotton phytopathogens, green nanoparticles, destructive pathogens, cotton agroecosystem, green preparation, seaweed‐based silver nanoliquid, cotton pathogenic fungi management, silver nanoparticles, Ag NP, Ag  相似文献   
713.
Microbial biofilm formation on implantable devices causes chronic infections that cannot be treated with existing antimicrobials. Quorum sensing inhibitors (QSIs) have recently emerged as novel antimicrobials for the prevention of biofilm formation. But blocking QS alone is insufficient to inhibit biofilm-associated chronic infections. Herein, chitosan hollow nanospheres are capped by bacteria-responsive β-casein to form a synergistic antifouling nanosystem consisting of a QSI and bactericide. β-casein is degraded by protease in a bacteria-colonized microenvironment in situ thus, QSI and bactericide are released sequentially. The release of QSI sensitises bacteria effectively through reduction of surface hydrophobicity, eDNA content, and lipopolysaccharide production in biofilms, amplifying the chemotherapeutic action of the bactericide. Compared to the uncoated surface, the coated surface inhibits biofilm formation and removes preformed biofilms of Pseudomonas aeruginosa PAO1 and methicillin-resistant Staphylococcus aureus by 1.8 logs and 1.9 logs of biomass inhibition, respectively. The coated catheters are found to stay clean for 30 days under artificial urine flow, while the uncoated catheters are clogged by bacterial biofilms within 5 days. Finally, the long term antifouling activity in vivo is confirmed. Overall, the nanosystem is devoted to making urinary catheters resistant to bacterial biofilm formation for the long term.  相似文献   
714.
The aim of this article is to show how Human Factors and Ergonomics (HFE) methods can be used to improve urban public infrastructure systems in densely populated countries, such as India. In this case, we use Accimap analysis with crowd flow approaches to inform safety and policy. We demonstrate the need for sociotechnical systemic safety by a case study of accident analysis of the Elphinstone Road railway station stampede. On September 29, 2017, the Elphinstone Road, Mumbai, India, railway platform bridge stampede killed at least 23 and injured 39 other commuters who traveled through the Mumbai Suburban railway. In this study, we understand the accident as it is presented in newspaper articles. We analyze the accident by a sociotechnical accident analysis method called the Accimap. The Accimap method helps by identification of various stakeholders and their interactions in the different levels of hierarchy in a sociotechnical system. This ensures moving away from individualistic and blame-based accounts of media reporting to a coherent sociotechnical account based on understanding the dynamics of the situation. The findings from the Accimap analysis identify the problem areas in the commuter transit system and provide recommendations. These recommendations range from commuter flow management to enforcement of rules for supporting pedestrian flow. The article concludes with an emphasis on the development of the sociotechnical dimension of public safety and infrastructure from a human factors perspective, above and beyond what is currently practiced in India.  相似文献   
715.
The recent emergence of pandemic of coronavirus (COVID-19) caused by SARS-CoV-2 has raised significant global health concerns. More importantly, there is no specific therapeutics currently available to combat against this deadly infection. The enzyme 3-chymotrypsin-like cysteine protease (3CLpro) is known to be essential for viral life cycle as it controls the coronavirus replication. 3CLpro could be a potential drug target as established before in the case of severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). In the current study, we wanted to explore the potential of fused flavonoids as 3CLpro inhibitors. Fused flavonoids (5a,10a-dihydro-11H-benzofuro[3,2-b]chromene) are unexplored for their potential bioactivities due to their low natural occurrences. Their synthetic congeners are also rare due to unavailability of general synthetic methodology. Here we designed a simple strategy to synthesize 5a,10a-dihydro-11H-benzofuro[3,2-b]chromene skeleton and it's four novel derivatives. Our structural bioinformatics study clearly shows excellent potential of the synthesized compounds in comparison to experimentally validated inhibitor N3. Moreover, in-silico ADMET study displays excellent druggability and extremely low level of toxicity of the synthesized molecules. Further, for better understanding, the molecular dynamic approach was implemented to study the change in dynamicity after the compounds bind to the protein. A detailed investigation through clustering analysis and distance calculation gave us sound comprehensive data about their molecular interaction. In summary, we anticipate that the currently synthesized molecules could not only be a potential set of inhibitors against 3CLpro but also the insights acquired from the current study would be instrumental in further developing novel natural flavonoid based anti-COVID therapeutic spectrums.  相似文献   
716.
This article proposes a computational fluid dynamics approach to simulate binder infiltration in 3D printing of sand molds using OpenFOAM facilitating the identification of suitable levers for application-specific material and process developments. A method for randomly generating powder bulks of designated powder size distributions (PSD) and procedures for automated analysis of the infiltration profile and volume are introduced. Simulation is utilized to investigate binder infiltration using different droplet spacings, representing different printheads’ resolutions. The apparent particle size at the exact location of the droplets’ impact, the droplets’ landing position in relation to the respective surface topography, and thus the statistical appearance of particle formations appear to be influencing the infiltration profile. High-speed camera observations show the plausibility of the predicted infiltration kinetics. An exemplary use case compares the predicted infiltration profiles to the compressive strength of specimens printed from silica sand with low binder contents. Simulation predicts an average infiltration of 250 μm that presumably achieves reliable bonding for layer thicknesses up to 365 μm. A decrease in strength with increasing layer thickness at constant binder contents can be found in the experiment – at layer thicknesses above 350 μm, only minor strengths are achieved.  相似文献   
717.
Effective on-road safety requires proper maintenance of vehicles. In the trucking sector in India, there is a need for supporting predictive maintenance to decrease downtime and improve safety. Improving maintenance in this sector involves certain challenges. First, most trucks are owned by small-scale fleet owners (trucks < 5). Second, maintenance is often handled by small-scale mechanic workshops. The fault diagnosis is very often limited to recognition by the driver and later reassessed by the mechanic by relying on the feel or the sound of the vehicle. Third, a majority of stakeholders in this sector—drivers, mechanics, and owners—have low levels of education. Despite these challenges, with the increase in the rate of digitalization, in the future, it will be easier to monitor the health of the parts of a truck. In addition, there is a developing trend of mobile phone and internet penetration in India that has leapfrogged a majority of Indians into becoming “emergent users” of information technology. Therefore, this article shows that sociotechnical approaches such as ecological interface design can be used to develop mobile interfaces for supporting predictive maintenance through health and usage monitoring of trucks for small-scale fleet owners in India. To develop the interface, a field study was conducted at several sites in the state of Tamil Nadu, India. The insights were used to develop scenarios and the abstraction hierarchy, which were later used creatively to develop the interface design for emergent users.  相似文献   
718.
Buffalo milk was utilised for preparing paneer samples after standardisation of protein:fat ratio to 0.68 with the addition of buffalo milk protein co-precipitates (BMPC). These paneer samples along with control paneer (from buffalo milk) were analysed for yield, composition, microstructure, sensory, texture profile and protein loss in whey during manufacture. Paneer prepared using BMPC was considerably higher in yield and recovery of total solids, protein and calcium content than control paneer and could withstand the frying conditions in terms of retention of shape and integrity. Texture profile analysis and microstructure evaluation revealed the differences in textural properties of paneer samples prepared using BMPC with control paneer.  相似文献   
719.
Liquid–liquid emulsions are used in many sectors such as personal care, home care, and food products. There is an increasing need for developing compact and modular devices for producing emulsions with desired droplet size distribution (DSD). In this work, we have experimentally and computationally investigated an application of vortex-based hydrodynamic cavitation (HC) device for producing emulsions. The focus is on understanding drop breakage occurring in a single-pass through the considered HC device. The experiments were performed for generating oil-in-water emulsion containing 1%–20% rapeseed oil. The effect of pressure drop across the HC device in the range of 50–250 kPa on drop breakage was examined. DSD of emulsions produced through a single pass was measured using the focussed beam reflectance measurements. Comprehensive computational fluid dynamics (CFD) model based on the Eulerian approach was developed to simulate multiphase cavitating flow. Using the simulated flow, population balance model (PBM) with appropriate breakage kernels was solved to simulate droplet breakage in a vortex-based HC device. The device showed an excellent drop breakage efficiency (nearly 1% which is much higher than other commercial devices such as rotor–stators or sonolators) and was able to reduce mean drop size from 66 to ~15 μm in a single pass. The CFD and PBM models were able to simulate DSD. The presented models and results will be useful for researchers and engineers interested in developing compact devices for producing emulsions of desired DSD.  相似文献   
720.
The porous and cellular architecture of scaffolds plays a significant role in mechanical strength and bone regeneration during the healing of fractured bones. In this present study, triply periodic minimal surface (TPMS)-based gyroid and primitive lattice structures were used to design the cellular porous biomimetic scaffolds with different unit cell sizes (4, 5, and 6). The fused filament fabrication-based 3D printing technology was used for the fabrication of polylactic acid scaffolds. The surface morphology and mechanical compressive strength of differently structured scaffolds were observed using scanning electron microscopy and a universal testing machine. The unit cell size of 4 showed higher compressive strength in both gyroid and primitive structured scaffolds compared to unit cell sizes 5 and 6. Moreover, the gyroid structured scaffolds have higher compressive strengths as compared to primitive structured scaffolds due to the higher bonding surface area at the intercalated layers of the scaffold. Hence, the mechanical strength of scaffolds can be tailored by varying the unit cell size and cellular structures to avoid stress shielding and ensure implant safety. These TPMS-based scaffolds are promising and can be used as bone substitute materials in tissue engineering and orthopedic applications.  相似文献   
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