Geotechnical Response Models for Steel Compliant Riser in Deepwater Clays

The touchdown zone (TDZ) often proves to be a spot where cyclic bending stresses are the largest and is therefore a critical location for fatigue. Catenary steel compliant pipelines or risers (SCRs) are subject of much ongoing research, particularly with respect to their fatigue life, which is strongly influenced by seabed soil conditions in the TDZ. This chapter reviews the recent publications that might have an impact on the SCR-seabed interaction. The review starts by looking at the SCR general arrangement. Thereafter, the focus moves to the review of the recent research that studied the interactions between deepwater SCRs and the seabed. In addition, the review went over the analysis techniques of the SCR, including the modelling philosophy and models for geotechnical response. The research gap and the need for future research are identified

Sustainable seabed mining: guidelines and a new concept for Atlantis II Deep

The feasibility of exploiting seabed resources is subject to the engineering solutions, and economic prospects. Due to rising metal prices, predicted mineral scarcities and unequal allocations of resources in the world, vast research programmes on the exploration and exploitation of seabed minerals are presented in 1970s. Very few studies have been published after the 1980s, when predictions were not fulfilled. The attention grew back in the last decade with marine mineral mining being in research and commercial focus again and the first seabed mining license for massive sulphides being granted in Papua New Guinea’s Exclusive Economic Zone.Research on seabed exploitation and seabed mining is a complex transdisciplinary field that demands for further attention and development. Since the field links engineering, economics, environmental, legal and supply chain research, it demands for research from a systems point of view. This implies the application of a holistic sustainability framework of to analyse the feasibility of engineering systems. The research at hand aims to close this gap by developing such a framework and providing a review of seabed resources. Based on this review it identifies a significant potential for massive sulphides in inactive hydrothermal vents and sediments to solve global resource scarcities. The research aims to provide background on seabed exploitation and to apply a holistic systems engineering approach to develop general guidelines for sustainable seabed mining of polymetallic sulphides and a new concept and solutions for the Atlantis II Deep deposit in the Red Sea.The research methodology will start with acquiring a broader academic and industrial view on sustainable seabed mining through an online survey and expert interviews on seabed mining. In addition, the Nautilus Minerals case is reviewed for lessons learned and identification of challenges. Thereafter, a new concept for Atlantis II Deep is developed that based on a site specific assessment.The research undertaken in this study provides a new perspective regarding sustainable seabed mining. The main contributions of this research are the development of extensive guidelines for key issues in sustainable seabed mining as well as a new concept for seabed mining involving engineering systems, environmental risk mitigation, economic feasibility, logistics and legal aspects

Cheiradone: a vascular endothelial cell growth factor receptor antagonist

<p>Abstract</p> <p>Background</p> <p>Angiogenesis, the growth of new blood vessels from the pre-existing vasculature is associated with physiological (for example wound healing) and pathological conditions (tumour development). Vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2) and epidermal growth factor (EGF) are the major angiogenic regulators. We have identified a natural product (cheiradone) isolated from a <it>Euphorbia </it>species which inhibited <it>in vivo </it>and <it>in vitro </it>VEGF- stimulated angiogenesis but had no effect on FGF-2 or EGF activity. Two primary cultures, bovine aortic and human dermal endothelial cells were used in <it>in vitro </it>(proliferation, wound healing, invasion in Matrigel and tube formation) and <it>in vivo </it>(the chick chorioallantoic membrane) models of angiogenesis in the presence of growth factors and cheiradone. In all cases, the concentration of cheiradone which caused 50% inhibition (IC₅₀) was determined. The effect of cheiradone on the binding of growth factors to their receptors was also investigated.</p> <p>Results</p> <p>Cheiradone inhibited all stages of VEGF-induced angiogenesis with IC₅₀values in the range 5.20–7.50 μM but did not inhibit FGF-2 or EGF-induced angiogenesis. It also inhibited VEGF binding to VEGF receptor-1 and 2 with IC₅₀values of 2.9 and 0.61 μM respectively.</p> <p>Conclusion</p> <p>Cheiradone inhibited VEGF-induced angiogenesis by binding to VEGF receptors -1 and -2 and may be a useful investigative tool to study the specific contribution of VEGF to angiogenesis and may have therapeutic potential.</p

Epidemiology of athletic injuries in classic ballet practitioners

Specific overloads of ballet practice may represent risk factors for injuries. The objective of this study was to analyze the epidemiology of typical injuries of ballet, including factors associated with history of injury in ballet practitioners. Studied subjects integrated 124 dancers, of both genders, from nine ballet schools from Campo Grande, Mato Grosso do Sul State, Brazil. To obtain information about injuries, we used a morbidity survey. Participants were divided into two groups: G1 (with injuries) and G2 (without injuries). In relation to prevalence of injuries, 89 cases were registered, and 61 dancers (49%) reported damages incidence, with record of 1.48 cases per practitioner. Moreover, the G2 presented higher body weight (G1: 51±8 versus G2: 55±10 kg) and training time (G1: 4.0±2.0 versus G2: 5.0±4.1 years). With respect to injury type, joints (32%) and muscle affections (25%) were the main occurrences in the lower limbs (85%) due to specific exercises (30%). Weekly exposure time was the most important mechanism to injury installation. The more important causal circumstance to injury occurrence was constituted by specific training (49%) and choreographic performance (41%). In conclusion, evidences have showed that joint injuries in lower limbs are the main classical ballet injuries in ballet practitioners, and weekly exposure time is the most important factor associated with injuries in classical ballet.Demandas específicas da prática de ballet podem representar fatores de risco para lesões musculoesqueléticas. Este estudo teve por objetivo analisar a epidemiologia das lesões típicas do ballet, com fatores associados ao histórico de lesão em bailarinos. A casuística integrou 124 participantes de ambos os sexos, procedentes de nove escolas e companhias de ballet de Campo Grande, no Mato Grosso do Sul. Para registro de lesões, utilizou-se um inquérito de morbidade referida. Os participantes foram distribuídos em dois grupos: G1, sem lesão, e G2, com lesão. Em relação à presença de lesão, foram registrados 89 casos, sendo que 61 bailarinos (49%) relataram terem se lesionado, com registro de 1,48 casos por praticante. O G2 apresentou maior massa corporal (G1: 51±8 versus G2: 55±10 kg) e tempo de treinamento (G1: 4,0±2,0 versus G2: 5,0±4,1 anos). Houve predomínio de lesões articulares (32%) e musculares (25%) nos membros inferiores (85%), decorrentes de exercícios específicos (30%). O maior tempo semanal de prática configurou o principal fator de risco para lesão. A circunstância que mais provocou lesões foi o treino específico (49%), seguido pelo ensaio de coreografia (41%). Conclui-se que as lesões articulares em membros inferiores são as principais lesões do ballet clássico, e o tempo semanal de exposição constitui o principal fator associado a lesões no ballet clássico.Demandas específicas de la práctica de balé pueden representar factores de riesgo para lesiones musculoesqueleticas. Eso estudio tuvo como objetivo analizar la epidemiologia de lesiones típicas del balé, con factores asociados a la historia de lesión en bailarines. Hubo la integración de 124 participantes de los dos géneros, procedentes de nueve escuelas de balé de Campo Grande, Mato Grosso do Sul, Brasil. Se utilizó una averiguación de morbidad referida para registrar las lesiones. Los participantes fueron distribuidos en dos grupos: G1, sin lesión, y G2, con lesión. Con relación a la presencia de lesión, se registraron 89 casos, y 61 bailarines (un 49%) reportaron lesiones con registro de 1,48 casos por practicante. El G2 presentó mayor masa corporal (G1: 51±8 versus G2: 55±10 kg) y tiempo de entrenamiento (G1: 4,0±2,0 versus G2: 5,0±4,1 años). Hubo predominancia de lesiones articulares (32%) y musculares (25%) en las extremidades inferiores (85%) originarias de ejercicios específicos (30%). El mayor tiempo semanal de práctica se configuró como el principal factor de riesgo para lesión. La circunstancia que más causó lesiones fue el entrenamiento específico (49%), seguido por el ensayo de coreografía (41%). Se concluso que las lesiones articulares en extremidades inferiores son las principales lesiones del balé clásico, y el tiempo semanal de exposición se constituye el principal factor asociado a las lesiones en el balé clásico

Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro

Protein glycation involves formation of early (Amadori) and late advanced glycation endproducts (AGEs) together with free radicals via autoxidation of glucose and Amadori products. Glycation and increased free radical activity underlie the pathogenesis of diabetic complications. This study investigated whether aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro in a cell-free system. Proteins were glycated by incubation with sugars (glucose, methylglyoxal or ribose) ±5–15 mg/mL of aged and fresh garlic extracts. Advanced glycation endproducts were measured using SDS-PAGE gels and by ELISA whereas Amadori products were assessed by the fructosamine method. Colorimetric methods were used to assess antioxidant activity, free radical scavenging capacity, protein-bound carbonyl groups, thiol groups and metal chelation activities in addition to phenolic, total flavonoid and flavonol content of aged and fresh garlic extracts. Aged garlic inhibited AGEs by 56.4% compared to 33.5% for an equivalent concentration of fresh garlic extract. Similarly, aged garlic had a higher total phenolic content (129 ± 1.8 mg/g) compared to fresh garlic extract (56 ± 1.2 mg/g). Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract and is more suitable for use in future in vivo studies

Assessment of the roughness factor effect and the intrinsic catalytic activity for hydrogen evolution reaction on Ni-based electrodeposits

The hydrogen evolution reaction (HER) was studied in 30 wt.% KOH solution at temperatures ranging between 30 and 80 °C on three type of electrodes: (i) rough pure Ni electrodeposits, obtained by applying a large current density; (ii) smooth NiCo electrodeposits; (iii) smooth commercial Ni electrodes. By using steady-state polarization curves and electrochemical impedance spectroscopy (EIS) the surface roughness factor and the intrinsic activities of the catalytic layers were determined. These techniques also permitted us to determine the mechanism and kinetics of the HER on the investigated catalysts. Different AC models were tested and the appropriate one was selected. The overall experimental data indicated that the rough/porous Ni electrode yields the highest electrocatalytic activity in the HER. Nevertheless, when the effect of the surface roughness was taken into consideration, it was demonstrated that alloying Ni with Co results in an increased electrocatalytic activity in the HER when comparing to pure Ni. This is due to an improved intrinsic activity of the material, which was explained on the basis of the synergism among the catalytic properties of Ni (low hydrogen overpotential) and of Co (high hydrogen adsorption).Isaac Herraiz-Cardona is grateful to the Ministerio de Ciencia e Innovacion (Spain) for a postgraduate grant (Ref. AP2007-03737). This work was supported by Generalitat Valenciana (Project PROMETEO/2010/023)Herraiz Cardona, I.; Ortega Navarro, EM.; Garcia-Anton, J.; Pérez-Herranz, V. (2011). Assessment of the roughness factor effect and the intrinsic catalytic activity for hydrogen evolution reaction on Ni-based electrodeposits. International Journal of Hydrogen Energy. 36(16):9428-9438. https://doi.org/10.1016/j.ijhydene.2011.05.047S94289438361

In vitro inhibitory activities of selected Australian medicinal plant extracts against protein glycation, angiotensin converting enzyme (ACE) and digestive enzymes linked to type II diabetes

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background There is a need to develop potential new therapies for the management of diabetes and hypertension. Australian medicinal plants collected from the Kuuku I’yu (Northern Kaanju) homelands, Cape York Peninsula, Queensland, Australia were investigated to determine their therapeutic potential. Extracts were tested for inhibition of protein glycation and key enzymes relevant to the management of hyperglycaemia and hypertension. The inhibitory activities were further correlated with the antioxidant activities. Methods Extracts of five selected plant species were investigated: Petalostigma pubescens, Petalostigma banksii, Memecylon pauciflorum, Millettia pinnata and Grewia mesomischa. Enzyme inhibitory activity of the plant extracts was assessed against α-amylase, α-glucosidase and angiotensin converting enzyme (ACE). Antiglycation activity was determined using glucose-induced protein glycation models and formation of protein-bound fluorescent advanced glycation endproducts (AGEs). Antioxidant activity was determined by measuring the scavenging effect of plant extracts against 1, 1-diphenyl-2-picryl hydrazyl (DPPH) and using the ferric reducing anti-oxidant potential assay (FRAP). Total phenolic and flavonoid contents were also determined. Results Extracts of the leaves of Petalostigma banksii and P. pubescens showed the strongest inhibition of α-amylase with IC50 values of 166.50 ± 5.50 μg/mL and 160.20 ± 27.92 μg/mL, respectively. The P. pubescens leaf extract was also the strongest inhibitor of α-glucosidase with an IC50 of 167.83 ± 23.82 μg/mL. Testing for the antiglycation potential of the extracts, measured as inhibition of formation of protein-bound fluorescent AGEs, showed that P. banksii root and fruit extracts had IC50 values of 34.49 ± 4.31 μg/mL and 47.72 ± 1.65 μg/mL, respectively, which were significantly lower (p < 0.05) than other extracts. The inhibitory effect on α-amylase, α-glucosidase and the antiglycation potential of the extracts did not correlate with the total phenolic, total flavonoid, FRAP or DPPH. For ACE inhibition, IC50 values ranged between 266.27 ± 6.91 to 695.17 ± 15.38 μg/mL. Conclusions The tested Australian medicinal plant extracts inhibit glucose-induced fluorescent AGEs, α-amylase, α-glucosidase and ACE with extracts of Petalostigma species showing the most promising activity. These medicinal plants could potentially be further developed as therapeutic agents in the treatment of hyperglycaemia and hypertension

Antiglycation and antioxidant properties of Momordica charantia

The accumulation of advanced glycation endproducts (AGEs) and oxidative stress underlie the pathogenesis of diabetic complications. In many developing countries, diabetes treatment is unaffordable, and plants such as bitter gourd (or bitter melon; Momordica charantia) are used as traditional remedies because they exhibit hypoglycaemic properties. This study compared the antiglycation and antioxidant properties of aqueous extracts of M. charantia pulp (MCP), flesh (MCF) and charantin in vitro. Lysozyme was mixed with methylglyoxal and 0–15 mg/ml of M. charantia extracts in a pH 7.4 buffer and incubated at 37°C for 3 days. Crosslinked AGEs were assessed using gel electrophoresis, and the carboxymethyllysine (CML) content was analyzed by enzyme-linked immunosorbent assays. The antioxidant activities of the extracts were evaluated using assays to assess DPPH (1,1-diphenyl-2-picryl-hydrazyl) and hydroxyl radical scavenging activities, metal-chelating activity and reducing power of the extracts. The phenolic, flavonol and flavonoid content of the extracts were also determined. All extracts inhibited the formation of crosslinked AGEs and CML in a dose-dependent manner, with MCF being the most potent. The antioxidant activity of MCF was higher than that of MCP, but MCP showed the highest metal-chelating activity. MCF had the highest phenolic and flavonoid contents, whereas MCP had the highest flavonol content. M. charantia has hypoglycaemic effects, but this study shows that M. charantia extracts are also capable of preventing AGE formation in vitro. This activity may be due to the antioxidant properties, particularly the total phenolic content of the extracts. Thus, the use of M. charantia deserves more attention, as it may not only reduce hyperglycaemia but also protect against the build-up of tissue AGEs and reduce oxidative stress in patients with diabetes