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The coastal engineering of land reclamation is increasingly important for space retention and creation in the context of sea-level rise and limited land area in coastal regions. Meanwhile, a huge amount of marine dredged sediment (MDS) is generated annually and disposed of as waste, causing serious environmental problems. To minimize such disposal and turn waste into resources for coastal engineering, MDS can be upcycled for in-situ marine sediment concrete (MSC) production. As a major concern, the durability of MSC remains elusive with an inadequate scientific understanding. In this paper, the durability of concrete involving MDS was investigated comprehensively from three aspects: physical attack, chemical attack, and inner quality. The accessible porosity was identified as the key factor affecting the durability of MSC. Practical measures were explored for the durability design of MSC. This study can pave the way for the sustainable use of MDS for marine construction, coastal protection, and land reclamation.

In three adult patients, two with atrial septal defect and one with Ebstein's anomaly, chronic atrial fibrillation was documented for 13, 21, and 3 years, respectively. Atrial compartment surgery was performed for ablation of the atrial fibrillation concomitant with repair of the cardiac defects. The operation was performed with traditional cardiopulmonary bypass and crystalloid cardioplegia myocardial protection. A U-shaped incision was made in the right atrium: a longitudinal incision 1 cm lateral and parallel to the sulcus terminalis, extending along the borders of the atrial septum to 3 cm (upper margin) and 1 cm (lower margin) distant to the tricuspid anulus. Cryolesions of the atrial isthmus between the upper incision margin and the tricuspid valve anulus were created at -60@? C for 180 seconds at a time. After the operation, all three patients had restored and maintained normal sinus rhythm during follow-up periods of 32, 16, and 3 months. Doppler echocardiography detected the recovery of atrial contractility in all three patients. Atrial compartment surgery is a simple and effective method for elimination of chronic atrial fibrillation associated with congenital heart defects. (J THORAC CARDIOVASC SURG 1996;111:231-7)

The presence of Δ3,5,Δ2,4-dienoyl-CoA isomerase in peroxisomes was demonstrated by determining the subcellular distribution of this enzyme in rat liver. The peroxisomal and mitochondrial forms of the isomerase exhibit similar chain length specificities and they are homologous as indicated by the recognition of the peroxisomal 66-kDa enzyme by an antiserum raised against the mitochondrial 32-kDa isomerase. This report demonstrates that peroxisomes contain all enzymes required for the β oxidation of unsaturated fatty acids with odd-numbered double bonds by a novel pathway in which double bonds are reductively removed by the NADPH-dependent 2,4-dienoyl-CoA reductase.Copyright 1995, 1999 Academic Press,Inc.

In remote islands and coastal areas, where there are no freshwater and river sand, the use of locally available seawater and marine sediments in mortar and concrete for building construction may be a better solution. Moreover, if there are no local materials for fabricating the formwork, 3D mortar/concrete printing may be considered. However, study on 3D printing using mortar/concrete made of seawater and marine sediments is still lacking. In this study, a series of mortar mixes made of seawater, coral sand, and glass or basalt fibers were produced to test their fresh and hardened properties for the purpose of developing 3D printable glass/basalt fiber reinforced seawater coral sand mortars. It was found that by adjusting the water reducer dosage, all the mortar mixes exhibited good buildability. The addition of glass or basalt fibers improved the flexural strength to some extent but slightly reduced the compressive strength. However, the flexural and compressive strengths of the printed specimens were significantly lower than those of the standard un-printed specimens. Overall, the fiber reinforced seawater coral sand mortar exhibits great potential to be applied as 3D printable cement-based material for use in remote areas.

•Alkali-activated material is an innovative and environmentally friendly-engineered material.•Geocrete exhibited greater long-term durability properties such as acid, corrosion, sulphate, and fire resistance.•Future investigation to study the aggregate content effect and additives on the engineering properties of geocretes.•Investigations aimed at user friendly systems, particularly non-corrosive alkali activators.

•Extrudable high strength FRC (strength>120 MPa) was developed.•Conceptual model for design of extrudable mixtures was presented.•Addition of nano calcium carbonate and fibers improved rheology and strength.•Steel fibers more effectively improved the strength than carbon and glass fibers.•Carbon and glass fibers more effectively improved interlayer bond than steel fibers.

From July 1992 to May 1994, 31 cases of obstructive azoospermia-induced infertility underwent 35 epididymal sperm aspiration procedures and assisted reproductive techniques. These included in-vitro fertilization (IVF), zygote intra-Fallopian transfer (ZIFT), subzonal insemination (SUZI) and intracytoplasmic sperm injection (ICSI) with embryo transfer or tubal embryo transfer. The motile spermatozoa were retrieved using a gauge 24 Medicut cannula and flush medium. Total oocyte fertilization rate was 23.4% and the clinical pregnancy rate was 12.5% (four out of 32 treatment cycles). Congenital absence of the vas deferens was found in 16 cases (51.6%) and secondary genital duct obstruction was present in 15 cases (48.4%). In all, 29 aspirations were retrieved from the caput of the epididymis and six from the epididymal body or tail. The fertilization rate for the caput spermatozoa was much less than that for other areas of the epididymis (P < 0.05). Though there were no predictable differences in fertilization rates between the congenital and acquired groups, by using epididymal spermatozoa for assisted reproduction, the congenital group seemed to have a stronger tendency to achieve pregnancy (20 versus 5.9%).

To determine the possibility of finding motile spermatozoa and spermatids in patients with high serum follicle stimulating hormone (FSH) and spermatogenetic disorders proven by pathology, 100 cases of male infertility were reviewed. Of these, 71 patients were found to have non-obstructive azoospermia or severe primary spermatogenetic disorders, and 20 had obstructive azoospermia. A prospective study of the most recent 51 cases was conducted. Multiple testicular tissue biopsies were examined by a pathologist and a well-trained gynaecological technician. The findings of spermatozoa, spermatids and serum FSH concentrations were compared among six different histological groups. It was concluded that 51.2% of the non-obstructive azoo-spermic and failed spermatogenetic patients had spermatids and even motile ‘shaking’ spermatozoa and should be re-evaluated. In the non-obstructive azoospermic patients here, almost all the motile spermatozoa and spermatids were found in patients with a serum FSH concentration of <30 mIU/ml. It is suggested that a testicular biopsy should be conducted in every case of non-obstructive azoospermia and spermatogenetic disorder, even in those patients with elevated serum FSH concentrations.