Analysis of middle-to-far wake behind floating offshore wind turbines in the presence of multiple platform motions

Understanding the unsteady characteristics of the mid-to-far wake and comprehension of the aerodynamic performance of floating offshore wind turbines is essential for the further development of offshore wind farms. In this perspective, a developed Actuator line model is utilized to analyze an offshore turbine on four different platforms. The model reliability was examined through three sets of validations involving turbine output in fixed and floating conditions and wake expansion in terms of size and rate. The affected relative velocity by the platform motion contributes to the wake deformation and temporal effects on induced velocity. Angular platform motions produce a non-axisymmetric helical wake that raises the chance of meandering wake patterns. It was founded although platform movement generally can boost the recovery of mean velocity value, it may amplify the amplitude of velocity deficit fluctuation at further downstream by encouraging interactions and merging vortex rings. Consequently, the wake propagates into a form of stronger circles whose period, strength, and center are functions of turbine movement and operation conditions. By providing a computationally efficient tool, the findings emphasize the importance of wake propagation in designing and assessing farm layouts that operate in the presence of significant multi-motions of floating offshore wind turbines

Curcuma purpurascens BI. rhizome accelerates rat excisional wound healing: involvement of Hsp70/Bax proteins, antioxidant defense, and angiogenesis activity

Elham Rouhollahi,1 Soheil Zorofchian Moghadamtousi,2 Fatemeh Hajiaghaalipour,3 Maryam Zahedifard,2 Faezeh Tayeby,2 Khalijah Awang,4 Mahmood Ameen Abdulla,3 Zahurin Mohamed1 1Pharmacogenomics Laboratory, Department of Pharmacology, Faculty of Medicine, 2Institute of Biological Sciences, Faculty of Science, 3Department of Biomedical Science, Faculty of Medicine, 4Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia Purpose: Curcuma purpurascens BI. is a member of Zingiberaceae family. The purpose of this study is to investigate the wound healing properties of hexane extract of C. purpurascens rhizome (HECP) against excisional wound healing in rats.Materials and methods: Twenty four rats were randomly divided into 4 groups: A) negative control (blank placebo, acacia gum), B) low dose of HECP, C) high dose of HECP, and D) positive control, with 6 rats in each group. Full-thickness incisions (approximately 2.00 cm) were made on the neck area of each rat. Groups 1–4 were treated two-times a day for 20 days with blank placebo, HECP (100 mg/kg), HECP (200 mg/kg), and intrasite gel as a positive control, respectively. After 20 days, hematoxylin and eosin and Masson’s trichrome stainings were employed to investigate the histopathological alterations. Protein expressions of Bax and Hsp70 were examined in the wound tissues using immunohistochemistry analysis. In addition, levels of enzymatic antioxidants and malondialdehyde representing lipid peroxidation were measured in wound tissue homogenates.Results: Macroscopic evaluation of wounds showed conspicuous elevation in wound contraction after topical administration of HECP at both doses. Moreover, histopathological analysis revealed noteworthy reduction in the scar width correlated with the enhanced collagen content and fibroblast cells, accompanied by a reduction of inflammatory cells in the granulation tissues. At the molecular level, HECP facilitates wound-healing process by downregulating Bax and upregulating Hsp70 protein at the wound site. The formation of new blood vessel was observed in Masson’s trichrome staining of wounds treated with HECP (100 and 200 mg/kg). In addition, HECP administration caused a significant surge in enzymatic antioxidant activities and a decline in lipid peroxidation.Conclusion: These findings suggested that HECP accelerated wound-healing process in rats via antioxidant activity, angiogenesis effect and anti-inflammatory responses involving Hsp70/Bax. Keywords: Zingiberaceae, wound closure, immunohistochemistry, antioxidant enzyme activity, inflammatory cell

The chemopreventive potential of Curcuma purpurascens rhizome in reducing azoxymethane-induced aberrant crypt foci in rats

Elham Rouhollahi,1 Soheil Zorofchian Moghadamtousi,2 Nawal Al-Henhena,3 Thubasni Kunasegaran,1 Mohadeseh Hasanpourghadi,4 Chung Yeng Looi,4 Sri Nurestri Abd Malek,2 Khalijah Awang,5 Mahmood Ameen Abdulla,3 Zahurin Mohamed1 1Pharmacogenomics Laboratory, Department of Pharmacology, Faculty of Medicine, 2Institute of Biological Sciences, Faculty of Science, 3Department of Biomedical Science, 4Cell Biology and Drug Discovery Laboratory, Department of Pharmacology, Faculty of Medicine, 5Department of Chemistry, University of Malaya, Kuala Lumpur, Malaysia Abstract: Curcuma purpurascens BI. rhizome, a member of the Zingiberaceae family, is a popular spice in Indonesia that is traditionally used in assorted remedies. Dichloromethane extract of C. purpurascens BI. rhizome (DECPR) has previously been shown to have an apoptosis-inducing effect on colon cancer cells. In the present study, we examined the potential of DECPR to prevent colon cancer development in rats treated with azoxymethane (AOM) (15 mg/kg) by determining the percentage inhibition in incidence of aberrant crypt foci (ACF). Starting from the day immediately after AOM treatment, three groups of rats were orally administered once a day for 2 months either 10% Tween 20 (5 mL/kg, cancer control), DECPR (250 mg/kg, low dose), or DECPR (500 mg/kg, high dose). Meanwhile, the control group was intraperitoneally injected with 5-fluorouracil (35 mg/kg) for 5 consecutive days. After euthanizing the rats, the number of ACF was enumerated in colon tissues. Bax, Bcl-2, and proliferating cell nuclear antigen (PCNA) protein expressions were examined using immunohistochemical and Western blot analyses. Antioxidant enzymatic activity was measured in colon tissue homogenates and associated with malondialdehyde level. The percentage inhibition of ACF was 56.04% and 68.68% in the low- and high-dose DECPR-treated groups, respectively. The ACF inhibition in the treatment control group was 74.17%. Results revealed that DECPR exposure at both doses significantly decreased AOM-induced ACF formation, which was accompanied by reduced expression of PCNA. Upregulation of Bax and downregulation of Bcl-2 suggested the involvement of apoptosis in the chemopreventive effect of DECPR. In addition, the oxidative stress resulting from AOM treatment was significantly attenuated after administration of DECPR, which was shown by the elevated antioxidant enzymatic activity and reduced malondialdehyde level. Taken together, the present data clearly indicate that DECPR significantly inhibits ACF formation in AOM-treated rats and may offer protection against colon cancer development. Keywords: colon cancer, PCNA, Zingiberacea

Chemopreventive evaluation of a Schiff base derived copper (II) complex against Azoxymethane-induced colorectal cancer in rats

Background: Based on the potential of Schiff base compounds to act as sources for the development of cancer chemotherapeutic agents, this in vivo study was performed to investigate the inhibitory properties of the synthetic Schiff base compound Cu(BrHAP)2 on colonic aberrant crypt foci (ACF). Methodology: This study involved five groups of male rats. The negative control group was injected with normal saline once a week for 2 weeks and fed 10% Tween 20 for 10 weeks, the cancer control group was subcutaneously injected with 15 mg/kg azoxymethane once per week for two consecutive weeks, the positive control group was injected with 15 mg/kg azoxymethane once per week for two consecutive weeks and 35 mg/kg 5-fluorouracil (injected intra-peritoneally) for 4 weeks, and the experimental groups were first injected with 15 mg/kg azoxymethane once per week for two consecutive weeks and then fed 2.5 or 5 mg/kg of the Schiff base compound once a day for 10 weeks. Application of the Schiff base compound suppressed total colonic ACF formation by up to 72% to 74% (P,0.05) when compared with the cancer control group. Analysis of colorectal specimens revealed that treatments with the Schiff base compound decreased the mean crypt scores in azoxymethane-treated rats. Significant elevations of superoxide dismutase, glutathione peroxidase and catalase activities and a reduction in the level of malondialdehyde were also observed. Histologically, all treatment groups exhibited significant decreases in dysplasia compared to the cancer control group (P,0.05). Immunohistochemical staining demonstrated down-regulation of the PCNA protein. Comparative western blot analysis revealed that COX-2 and Bcl2 were up-regulated and Bax was down-regulated compared with the AOM control group. Conclusion: The current study demonstrated that the Cu(BrHAP)2 compound has promising chemoprotective activities that are evidenced by significant decreases in the numbers of ACFs in azoxymethane-induced colon cancer