A comprehensive investigation into the hydrodynamic and capture/retention performance of a gross pollutant trap

A novel and comprehensive testing approach to examine the performance of gross pollutant traps (GPTs) was developed. A proprietary GPT with internal screens for capturing gross pollutants—organic matter and anthropogenic litter—was used as a case study. This work is the first investigation of its kind and provides valuable practical information for the design, selection and operation of GPTs and also the management of street waste in an urban environment. It used a combination of physical and theoretical models to examine in detail the hydrodynamic and capture/retention characteristics of the GPT. The results showed that the GPT operated efficiently until at least 68% of the screens were blocked, particularly at high flow rates. At lower flow rates, the high capture/retention performance trend was reversed. It was also found that a raised inlet GPT offered a better capture/retention performance. This finding indicates that cleaning operations could be more effectively planned in conjunction with the deterioration in GPT’s capture/retention performance

Outline of a Theory of non-Rankine-Hugoniot Shock Wave in Weak Mach Reflection

At the previous AFMC, the background for expecting a departure from Rankine-Hugoniot theory at the base of the reflected shock wave in weak Mach reflection was exposed. The results of some pertinent experiments performed in the supersonic wind tunnel were then presented. They confirmed the hypothesised irregular behaviour. In the present contribution, the elaboration of a theory of transgressed shock wave properties is presented. This concept enables to calculate the modified jump process. It fully accounts for the known experimental observations. It is the unyielding boundary conditions that prevail beyond regular reflection which force this remarkable deviation from the classical shock wave theory to take place

Study on Retrofitting of RC Column Using Ferrocement Full and Strip Wrapping

Ferrocement is one of the cement-based composites used for retrofitting and rehabilitation among many applications. Ferrocement is one of the reinforced concrete form with lightweight and thin composite with durability and environmental resistant that strengthen the conventional RC columns to increase its strength and serviceability. This paper examines the performance of the ferrocement wrapping in RC columns experimentally with numerical simulation using ANSYS19. Totally sixteen number of RC column of size 150 mm × 150 mm in cross section and 450 mm in length were cast and tested in laboratory. Twelve are retrofitted columns with respect to volume fraction and wrapping technique. Six columns were retrofitted by full wrapping technique and six columns of strip wrapping technique. The remaining four columns are control columns in virgin condition to compare with the retrofitted columns. Concerning the volume fraction of each specimen, the number of pre-woven mesh layers were single layer, double layer and three layers. C30 concrete grade adopted in all specimens as per ACI Committee 211-1.91 with 4H8 longitudinal reinforcement and H6 of 75mm c/c ties. As the previous researchers examined the ferrocement and proved its efficiency. This study aims to examine the ferrocement in full and strip wrapping technique to compare their efficiency to increase the strength. Finite element analysis using ANSYS19 adopted to compare the experimental data with the numerical simulation. The results are analyzed and observed that the ferrocement has increased the confinement and strength of the RC columns.

Synergistic Effects of d-Tocotrienol and Xanthorrhizol in Prostate Cancer Cells

Background: Approximately one in seven American men will be diagnosed with prostate cancer during their lifetime. The mevalonate pathway produces essential intermediates for the post-translational prenylation and dolichylation of growth-associated proteins including Ras, nuclear lamins and growth factor receptors. Dysregulation of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme of the mevalonate pathway, in prostate cancer cells supports tumor growth and therefore can be targeted for prostate cancer prevention and therapy. Previous studies have shown that isoprenoids including tocotrienols and xanthorrhizol suppress the growth of prostate cancer cells with concomitant downregulation of HMG CoA reductase. Objective: To determine the synergistic effects of d-δ-tocotrienol and xanthorrhizol on growth of human DU-145 prostate carcinoma cells. Methods: DU-145 cells were incubated with d-δ-tocotrienol and xanthorrhizol, individually and in blends, for 72 hours before viable cells were quantified by CellTiter 96® Aqueous One Solution. The impacts of these compounds, individually and in combination, on cell cycle distribution and the expression of cell cycle related proteins in DU-145 cells were evaluated by flow cytometry and Western-blot in follow-up studies. Statistical analysis: All experiments were repeated 3 times. One-way analysis of variance (ANOVA) was performed to assess the differences between groups using PrismⓇ 4.0 software (GraphPad Software Inc., San Diego, CA). Differences in means was assessed using Tukey’s test. Levels of significance are indicated as P \u3c 0.05. Results: Blends of d-δ-tocotrienol and xanthorrhizol showed greater inhibition of cell growth than those of individual compounds. Current results did not show a significant change in cell cycle distribution or down regulation of Cdk4 and cyclin D1 with the combination of compounds. The level of procaspase-3 for apoptosis initiation was also not altered. Conclusion: Further studies are warranted to confirm these initial findings and understand the mechanisms underlying the combined effect of d-δ-tocotrienol and xanthorrhizol on cell proliferation

snRNA Catalysts in the Spliceosome’s Ancient Core

The spliceosome, an assembly of snRNAs and proteins, catalyzes the removal of introns from premessenger RNAs. A new study identifies specific phosphates in the U2-U6 snRNA complex that position two catalytic metals. Remarkably, these correspond precisely to metal-binding phosphates in a homologous structure of Group II self-splicing introns, long proposed to be the ribozyme progenitor of spliceosome

GBSV Resource Guide and Review for The University of Western Ontario and Surrounding Area

During the 2021-2022 academic year, gender-based violence and sexual assault became a major topic of discussion due to a number of troubling incidents throughout the year. One of the largest calls to action by the student body was for more resources and trainings. This paper compiles the resources and trainings that can be found on campus of the University of Western Ontario and in the surrounding areas into a cohesive list of major relevant sources. The goal of this paper is to amplify the many different programs already in place that can be added to the training cohorts or made available for students to take apart in if desired

The hydrodynamic and capture/retention performance of a gross pollutant trap

This research shows that gross pollutant traps (GPTs) continue to play an important role in preventing visible street waste—gross pollutants—from contaminating the environment. The demand for these GPTs calls for stringent quality control and this research provides a foundation to rigorously examine the devices. A novel and comprehensive testing approach to examine a dry sump GPT was developed. The GPT is designed with internal screens to capture gross pollutants—organic matter and anthropogenic litter. This device has not been previously investigated. Apart from the review of GPTs and gross pollutant data, the testing approach includes four additional aspects to this research, which are: field work and an historical overview of street waste/stormwater pollution, calibration of equipment, hydrodynamic studies and gross pollutant capture/retention investigations. This work is the first comprehensive investigation of its kind and provides valuable practical information for the current research and any future work pertaining to the operations of GPTs and management of street waste in the urban environment. Gross pollutant traps—including patented and registered designs developed by industry—have specific internal configurations and hydrodynamic separation characteristics which demand individual testing and performance assessments. Stormwater devices are usually evaluated by environmental protection agencies (EPAs), professional bodies and water research centres. In the USA, the American Society of Civil Engineers (ASCE) and the Environmental Water Resource Institute (EWRI) are examples of professional and research organisations actively involved in these evaluation/verification programs. These programs largely rely on field evaluations alone that are limited in scope, mainly for cost and logistical reasons. In Australia, evaluation/verification programs of new devices in the stormwater industry are not well established. The current limitations in the evaluation methodologies of GPTs have been addressed in this research by establishing a new testing approach. This approach uses a combination of physical and theoretical models to examine in detail the hydrodynamic and capture/retention characteristics of the GPT. The physical model consisted of a 50% scale model GPT rig with screen blockages varying from 0 to 100%. This rig was placed in a 20 m flume and various inlet and outflow operating conditions were modelled on observations made during the field monitoring of GPTs. Due to infrequent cleaning, the retaining screens inside the GPTs were often observed to be blocked with organic matter. Blocked screens can radically change the hydrodynamic and gross pollutant capture/retention characteristics of a GPT as shown from this research. This research involved the use of equipment, such as acoustic Doppler velocimeters (ADVs) and dye concentration (Komori) probes, which were deployed for the first time in a dry sump GPT. Hence, it was necessary to rigorously evaluate the capability and performance of these devices, particularly in the case of the custom made Komori probes, about which little was known. The evaluation revealed that the Komori probes have a frequency response of up to 100 Hz —which is dependent upon fluid velocities—and this was adequate to measure the relevant fluctuations of dye introduced into the GPT flow domain. The outcome of this evaluation resulted in establishing methodologies for the hydrodynamic measurements and gross pollutant capture/retention experiments. The hydrodynamic measurements consisted of point-based acoustic Doppler velocimeter (ADV) measurements, flow field particle image velocimetry (PIV) capture, head loss experiments and computational fluid dynamics (CFD) simulation. The gross pollutant capture/retention experiments included the use of anthropogenic litter components, tracer dye and custom modified artificial gross pollutants. Anthropogenic litter was limited to tin cans, bottle caps and plastic bags, while the artificial pollutants consisted of 40 mm spheres with a range of four buoyancies. The hydrodynamic results led to the definition of global and local flow features. The gross pollutant capture/retention results showed that when the internal retaining screens are fully blocked, the capture/retention performance of the GPT rapidly deteriorates. The overall results showed that the GPT will operate efficiently until at least 70% of the screens are blocked, particularly at high flow rates. This important finding indicates that cleaning operations could be more effectively planned when the GPT capture/retention performance deteriorates. At lower flow rates, the capture/retention performance trends were reversed. There is little difference in the poor capture/retention performance between a fully blocked GPT and a partially filled or empty GPT with 100% screen blockages. The results also revealed that the GPT is designed with an efficient high flow bypass system to avoid upstream blockages. The capture/retention performance of the GPT at medium to high inlet flow rates is close to maximum efficiency (100%). With regard to the design appraisal of the GPT, a raised inlet offers a better capture/retention performance, particularly at lower flow rates. Further design appraisals of the GPT are recommended