Spatiotemporal dispersal study of mangrove Avicennia marina and Rhizophora apiculata propagules

The propagule dispersal pattern of the two common mangrove species, Avicennia marina (Forsk.) Vierh. and Rhizophora apiculata Blume at a mangrove fringed coast, in the southwest tip of Penang Island was examined. Propagule dispersal study of both species were carried out by release and recapture method, while early developments of propagule were observed by an on-site tethering system. A. marina propagules recorded higher dispersal rate as compared to R. apiculata. After 60 tidal cycles, almost all propagules had moved away from the initial release site under the influence of strong wave current. The A. marina propagules were observed to grow better and faster than the R. apiculata propagules. However, the propagules of both species eventually failed to establish at the study site due to strong wave effect as well as unfavourable soil condition. A. marina and R. apiculata were found to adopt different strategies in propagule dispersal and early growth. A. marina was notably better adapted to thrive in the coastal environment. In a similar open coastal area, wave current and soil condition are suggested to be the most critical factors affecting the mangrove propagule dispersal and early establishment

Asian venous thromboembolism guidelines: updated recommendations for the prevention of venous thromboembolism

The Asian venous thromboembolism (VTE) prophylaxis guidelines were first published in 2012. Since its first edition, the Asian Venous Thrombosis Forum (AVTF) working group have updated the Asian VTE epidemiology and reviewed issues that were not addressed in the previous guidelines. The authors noted that the rising incidence of VTE across Asia may be attributable to aging population, dietary changes, and increasing incidence of obesity and diabetes. The new additions in the guideline include role of thrombophilia in VTE, bleeding risk in Asians, individual risk assessment, updates in the prevention of VTE in medically ill, bariatric surgery, cancer, orthopedic and trauma patients. The influence of primary thrombophilia in perioperative VTE is still unclear. The secondary risk factors, however, are similar between Asians and Caucasians. The group found no evidence of increased risk of bleeding while using pharmacological agents, including the use of novel anti-coagulants. At present, Caprini risk assessment model is widely used for individual risk assessment. Further validation of this model is needed in Asia. In medically ill patients, pharmacological agents are preferred if there is no bleeding risk. Intermittent pneumatic compression device (IPC) is recommended in patients with bleeding risk but we do not recommend using graduated compressive stockings. In bariatric patients, data on VTE is lacking in Asia. We recommend following current international guidelines. A high index of suspicion should be maintained during postbariatric surgery to detect and promptly treat portomesenteric venous thrombosis. Different cancer types have different thrombotic risks and the types of surgery influence to a large extent the overall VTE risk. Cancer patients should receive further risk assessment. In patients with higher thrombotic risk, either due to predisposing risk or concomitant surgery, low molecular weight heparin is indicated. Different countries appear to have different incidence of VTE following trauma and major orthopedic surgery. We recommend mechanical prophylaxis using IPC as the main method and additional pharmacological prophylaxis if the thrombotic risk is high. As for obstetric practice, we propose adherence to the UK Greentop guideline that is widely accepted and utilized across Asia. To improve VTE thromboprophylaxis implementation in the region, we propose that there should be better health education, establishment of hospital-based guidelines and multidisciplinary collaboration

RETRACTED ARTICLE: Removal of heavy metals from plating wastewater by using complexation-ultrafiltration process

Complexation-ultrafiltration process was employed to remove Ni( II ), Cu( II ), Zn( II ) and Cr( III ) from plating wastewater. Polyacrylic acid sodium (PAASS) as a water-soluble polymer was used for complexing the cationic forms of the heavy metals before filtration. The size of the complex has to be larger than the selected membranes so the complex can be retained. Permeate water is then purified from the heavy metals. Filtration experiments were performed with ultrafiltration membrane system, equipped with a polysulfone memebrane with a 10,000 Da cut-off. Different parameters, affecting the percentage rejection of the metals, such as pH, loading ratio, and permeate flux (FVC) have been investigated. The concentrated retentates were used further for the decomplexation, after the decomplexation, diafiltration experiments were carried out at pH 1.5 using dilute H2SO4 solution. All the four metals were found to be extracted from the metal-PAASS complexes with satisfaction. It was also found that the complexing performance of the PAASS regenerated did not change compared with the fresh PAASS. ? 2011 IEEE