Flexural Wrinkling Behaviour of Lightly Profiled Sandwich Panels

In Australia, sandwich panels are commonly made of flat or lightly profiled steel faces and expanded polystyrene foam cores. Flexural wrinkling is often the governing criterion in the design of these panels. The use of lightly profiled faces is expected to increase the flexural wrinkling stress considerably whereas the presence of joints between the polystyrene foam slabs in the transverse direction introduces a reduction to the flexural wrinkling stress. Therefore a series of full scale experiments and finite element analyses were conducted to evaluate the effects of lightly profiled faces and transverse joints on the flexural wrinkling stress of panels subjected to a lateral pressure loading. This paper presents the details of this investigation, the results and comparison with available theoretical and design solutions

Behaviour of LiteSteel Beams Subject to Combined Shear and Bending Actions

This paper presents the details of a numerical study of a cold-formed steel beam known as LiteSteel Beam (LSB) subject to combined shear and bending actions. The LSB sections are produced by a patented manufacturing process involving simultaneous cold-forming and electric resistance welding. They have a unique shape of a channel beam with two rectangular hollow flanges. To date, however, no investigation has been conducted into the strength of LSB sections under combined shear and bending actions. Hence a numerical study was undertaken to investigate the behaviour and strength of LSBs subject to combined shear and bending actions. In this research, finite element models of LSBs were developed to simulate the combined shear and bending behaviour and strength of LSBs. They were then validated by comparing their results with test results and used in a parametric study. Both experimental and finite element analysis results showed that the current design equations are not suitable for combined shear and bending capacities of LSBs. Hence improved design equations are proposed for the capacities of LSBs subject to combined shear and bending actions

Evaluation of spermatogenic, aphrodisiac and anti-oxidant activity of classical siddha drug Thathu Viruthi Chooranam in rodents

Herbal preparations in Siddha system of medicine always have a unique range of beneficial effect because of its wonderful therapeutic value without causing adverse effects. Here the drug Thathu Viruthi Chooranam was pharmacologically evaluated and scientifically validated and standardized. The ingredients of the drug was identified and authenticated by Gunapadam experts. The drug was prepared as per classical Siddha literary procedure and subjected to various studies to reveal its potency and efficacy of the drug. The organoleptic character and physicochemical studies were made into standardization of the drug TVC. From the above studies the TVC is standardized as per AYUSH guidelines. The biochemical and instrumental analysis was made to know the presence of active ingredients in the drug which is responsible for its activity. Here, the biochemical analysis showed the presence of Calcium, Magnesium, Zinc, Sulphate, Chloride by its synergistic effects, the drug as activity against the disease. In instrumental analysis, FTIR showed the OH group has higher potential towards inhibitory activity against microorganisms. Sometimes the presence of Phenols in medicinal plants possess highly Anti-Oxidant property which enhances the drug effect against the disease. SEM picture explained the particle size of the drug. In ICP-OES described about the absence of heavy metals and its permissible limits which showed the safety of the drug. TLC plate showed different colour phytoconstituents of chloroform extract of TVC. The bands revealed presence of seven violets, four reds, two greens, one blue, one white and one yellow showing the presence of alkaloids, glycosides, phenols, triterpenes, flavonoids and quinines. The drug Thathu Viruthi Chooranam was proved that it is free from toxicity through the acute and 28 days repeated oral toxicity study as per the OECD guidelines. In acute toxicity study there was no mortality of rats observed. In 28 days repeated oral toxicity study, the obtained results of haematological, biochemical, urinary parameters were normal. The histopathological findings did not show any abnormalities. And this herbal formulation possess more potent Aphrodisiac activity in ethanol treated male rats. This trial drug Thathu Viruthi Chooranam exhibits high range of Spermatogenic activity in ethanol induced male rats. Most of the research findings already reported that the role of antioxidant is essential to treat male infertility. Here the trial drug possess strong antioxidant activity. These results conclude that the drug Thathu Viruthi Chooranam is a best drug of choice for the treatment of male infertility. By analyzing all those findings, it is proved that the drug Thathu Viruthi Chooranam has high range of therapeutic value and the safety of the drug for clinical use is ensured. So, it is confirmed that the herbal formulation Thathu Viruthi Chooranam may never cause any adverse effects in clinical use. The preparation of the drug is cost effective too. So, the clinical trials have to be followed on the drug Thathu Viruthi Chooranam. Thus can treat the infertile males effectively and help them to achieve their dream of producing their own offspring. CONCLUSION: The drug “Thathu Viruthi Chooranam” was prepared as per the classical Siddha literature Sarabenthirar Vaithiya Rathnavali. It fulfills all the standardization parameters of Chooranam as mentioned in AYUSH guidelines. The results of biochemical analysis showed the presence of acid and basic radicals in the sample. The presence of alkaloids, flavonoids, glycosides, tannins, triterpenoids were identified in the choloroform and methanolic extract of Thathu Viruthi Chooranam through Phytochemical analysis. TLC plate showed different colour phytoconstituents of chloroform extract of TVC. FT-IR Study results exhibits the presence of some organic functional groups such as alcohols, phenols, alkenes, amines, aromatics, aliphatic amines, alkyl halides. SEM analysis showed the objects of sizes ranging from 3μm to5 μm. XRD pattern of the trial drug Thathu Viruthi Chooranam shows good crystalinity. Based on OECD 423 the trial drug Thathu Viruthi Chooranam is considered as non toxic up to the dose of 2000mg/kg. The drug Thathu Viruthi Chooranam possess the potent Aphrodisiac activity in ethanol treated male rats. The drug Thathu Viruthi Chooranam could be confirmed as no-observedadverse-effect level (NOAEL) drug as it acts harmlessly under the current normal usage and this phenomenon is considered to be of no toxicological concern. High antioxidant therapeutic nature was evaluated in the drug Thathu Viruthi Chooranam through DPPH Scavenging assay. Because of this anti-oxidant property, it can be used as a drug to treat the male infertility. Hence it is proved that the drug Thathu Viruthi Chooranam was pharamacollogicaly evaluated for the property of Spermatogenic, Aphrodisiac and Antioxidant activity

Cross Pixel Optical Flow Similarity for Self-Supervised Learning

We propose a novel method for learning convolutional neural image representations without manual supervision. We use motion cues in the form of optical flow, to supervise representations of static images. The obvious approach of training a network to predict flow from a single image can be needlessly difficult due to intrinsic ambiguities in this prediction task. We instead propose a much simpler learning goal: embed pixels such that the similarity between their embeddings matches that between their optical flow vectors. At test time, the learned deep network can be used without access to video or flow information and transferred to tasks such as image classification, detection, and segmentation. Our method, which significantly simplifies previous attempts at using motion for self-supervision, achieves state-of-the-art results in self-supervision using motion cues, competitive results for self-supervision in general, and is overall state of the art in self-supervised pretraining for semantic image segmentation, as demonstrated on standard benchmarks

Endovascular Management of Traumatic Iliac Vessel Disruption—Report of Two Cases

AbstractVascular injuries in a multi-trauma patient are associated with significant cardiovascular instability and organ injury. Injuries with active bleeding are best treated with a quick, safe and the least less invasive procedure available to the trauma surgeon. We report two cases of blunt trauma induced common and external iliac vessel injury, managed by endovascular treatment. In the second case, endovascular treatment prevented histological examination of the artery, which would have revealed an alternative diagnosis

Thermal analysis of SUS 304 stainless steel using ethylene glycol/nanocellulose-based nanofluid coolant

Green cooling system usage in machining is getting favors to minimize the environmental effect such as pollutions. Around 20% of the machining cost is about coolant usage in flooded cooling technique. Even though coolant has a reasonably low cost, their handling and disposing cost are very high and also, threatening toxic contents, disposal of used coolant is a big problem as it can lead to hazardous effect to the machining operates as well as to the environment. As an alternative, a cooling technique known as minimum quantity lubrication (MQL) was introduced in the machining operation. For MQL technique, the coolant should exhibit superior properties which are effective in machining operation when compared with the conventional machining coolant which is metal working fluid (MWF). Owing to the technology advancements by nanotechnology in nanomaterial, the nanofluid is a promising coolant that can replace the conventional machining coolant. In the present work, ethylene glycol/nanocellulose-based nanofluid is evaluated in terms of its thermo-physical properties and its effectiveness in machining performances which is temperature distribution in cutting tool and compare its effectiveness with MWF. Its effectiveness is tested in turning machining operation of SUS 304 stainless steel using cemented tungsten-cobalt (WC-Co)-coated carbide cutting insert. The turning operation by using ethylene glycol/nanocellulose-based nanofluid coolant with 0.5 vol% which exhibit a superior thermal conductivity of 0.449 W/m K than 0.267 W/m K thermal conductivity of MWF at 30 °C. The recorded lower amount of heat transfer to the cutting tool is 863 J compared with 1130 J when using MWF. On the other hand, the maximum temperature reading recorded at chip formed by using MWF is 225 °C whereas by using nanofluid is 154 °C which promises lower temperature distribution to chip formed during the machining operation. Also, the functionality of nanofluid as a thermal transport during machining is proven via chip formation observation analysis and scanning electron microscope (SEM) with energy-dispersive X-ray (EDX) spectrum analysis

Statistical model for impact and energy absorption of 3D printed coconut Wood-PLA

Fused deposition modeling (FDM)-3D printing has been the favored technology to build functional components in various industries. The present study investigates infill percentage and infill pattern effects on the printed parts’ impact properties through the 3D printing technique using coconut wood-filled PLA composites. Mathematical models are also proposed in the present study with the aim for future property prediction. According to the ASTM standard, fifteen specimens with different parameter combinations were printed using a low-cost FDM 3D printer to evaluate their impact properties. Statistical analysis was performed using MINITAB to validate the experimental data and model development. The experimental outcomes reveal the honeycomb pattern with 75% infill density achieves the highest energy absorption (0.837 J) and impact energy (5.1894 kJ/m2). The p-value from statistical analysis clearly shows that all the impact properties are less than the alpha value of 0.05, suggesting all the properties are vital to determine the impact properties. The validation process affirms that the generated mathematical model for the energy absorbed and the impact energy is reliable at an acceptable level to predict their respective properties. The errors between the experimental value and the predicted value are 3.98% for the energy absorbed and 4.06% for impact energy. The findings are expected to provide insights on the impact behavior of the coconut wood-filled PLA composites prepared by FDM-3D printing and a mathematical model to predict the impact properties

Green synthesis of ZnO nanoparticles and their photocatalyst degradation and antibacterial activity

The current study aimed to synthesize nanoparticles of Zinc oxide (ZnO) using the extract of Acalypha indica leaves and their photocatalyst degradation and antibacterial properties were also measured. The biosynthesized nanoparticles were analyzed using XRD, UV-visible, FT-IR, and SEM with EDAX, DLS, PL, and Zeta potential analysis. The synthesized nanoparticles had a mean size of 16 nm measured by XRD which was highly pure, and their spherical shape was confirmed by SEM. The UV-visible confirmed that ZnO nanoparticles have a direct band gap energy is 3.34 eV. The measured zeta size and potential of synthesized nanoparticles were 46 nm and -27 mV, respectively, determined by the DLS technique can be considered moderately stable colloidal solutions. The FT-IR analysis confirmed the presence of functional groups in the leaf extract and the ZnO nanoparticles. The biosynthesized ZnO nanoparticles have a homogeneous spherical morphology and the average particle is 35 nm. The PL analyses performed on synthesized nanoparticles showed a sharp blue band at 362 nm, which was attributed to the defects of structure in ZnO crystals. During natural sunlight illumination, ZnO nanoparticles demonstrated notable degradation of the dye methyl blue (MB). At 90 min of illumination, the degradation efficiency achieved was 96 %. Antibacterial properties were observed for synthesized nanoparticles against four bacterial strains, including Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The highest zone of inhibition was observed against Escherichia coli (25.2 mm). Overall, these studies indicate that Acalypha indica is a good sell for planting, and has the greatest chance of being used to develop nanoparticles for protection against environmental pollution and human health