Status, prospects and potentials of echinoid sea urchins in Malaysia

Among the bottom-dwelling invertebrates, sea urchins have been considered as the high-valued new marine bioresource in Asia. They inhabit the depths of coral reefs and rocky shores that are covered with coralline algae and seaweeds. They are usually spherical in shape, and their whole body is covered by numerous thorns or spines that act as defense mechanism against predators. The sea urchin gonad has been used as luxury food and folk medicine by the peoples of certain countries. For this reason, sea urchin became an important product and fetches high price in international markets. It also plays an important role towards providing employment opportunity and income source to the coastal communities in many Pacific island countries including Malaysia. Sea urchin gonad is very rich in essential proteins, lipids and bioactive compounds having profound nutraceutical and pharmaceutical importance. Nowadays, sea urchins have been harvested for trade with Asia and are perhaps one of the worthy exports from the Indo-Pacific islands. Unluckily, owing to increasing demand and prices, combined with the development of cash economies and growing coastal populations, it has led to extensive overfishing of the resource across much of this region, especially in Pulau Bum Bum near Semporna between Philippines and Eastern Malaysia. Nevertheless, some Pacific island countries have completed research trials on breeding, nursing and culture techniques, but such types of research works are yet to be completely explored and determined in Malaysia. In the recent years, undiscriminating catching and over-exploitation of sea urchin turns out to be excessive and disrupts its sustainability. Because of this prevalent situation, aquaculture of sea urchins through the appropriate breeding, seed production and culture techniques in captivity should be the best alternative to solve these problems in a worthwhile and sustainable manner

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

A New Generalized Step-Down Single-Stage AC/AC Power Converter

Most traditional AC/AC power converters suffer from power quality problems and multi-stage power conversion losses. The rectifier and inverter-based AC/AC converter topology not only increases multi-stage power conversion losses, but also increases the volume, weight, and cost, and decreases the longevity of the converter due to the DC-link capacitor, line filter and electromagnetic interference (EMI) filter. High-frequency (about 10 kHz) switching advanced pulse width modulation techniques are generally used in order to compensate the power quality problems, which increase the switching losses and introduce the EMI problems. In this paper, a new generalized step-down single-stage line-frequency switching AC/AC power converter topology is proposed. The proposed converter uses line-frequency switching, and does not require any pulse width modulation techniques. The proposed topology offers promising performances in terms of lower order harmonics, total harmonic distortion, the elimination of DC-link capacitors and EMI filters, and switching losses. The circuit was designed and simulated in a MATLAB/Simulink environment. A scaled-down laboratory prototype of the proposed topology was developed in order to validate the feasibility. The experimental and simulation results reveal the feasibility of the proposed generalized step-down single-stage converter topology, and its excellent features