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Reuse and recycling of non-hazardous construction and demolition waste and industrial byproducts in the construction industry is vital to promote environmentally sound waste management. In particular, the effective utilization of sludge and waste clay bricks is greatly required in developing countries. This paper studied compaction characteristics and the California bearing ratio (CBR) of water treatment sludge (WTS) blended with clay brick aggregates for the road subgrade application. Raw and waste clay bricks from Vietnam were used for preparing clay brick (CB) and recycled clay brick (RCB) aggregates of three different particle sizes, Coarse 10- 30 mm, Graded 2-30 mm, and Fine 2-10 mm. In addition, fine residues of clay bricks with a size of < 2 mm were tested. WTS sieved under 2.0 mm blended with CB/RCB aggregates with different mixing proportions (f) were used for compaction and CBR tests in the laboratory. Results showed that the measured maximum dry densities (MDD) were dependent solely on mixing proportion f and increased linearly with f irrespective of blended fractions of CB/RCB aggregates. Unlike MDD, the measured CBR was dependent on both f and blended fractions. Especially, the WTS blended with coarse and graded fractions with a range of 60 ≤ f ≤ 80% showed a significant improvement in CBR (>100%). Due to its limited particle breakage and high CBR, the WTS blended with graded CB/RCB aggregates was preferable for the road subgrade application. [ABSTRACT FROM AUTHOR]

Introduction: Aortic mural thrombosis associated with a malignant disease is rare, and whether anticoagulation therapy or surgical treatment is the more definitive primary treatment remains uncertain. This study aims to determine the best treatment strategy for aortic thrombosis in a patient with a malignant disease. Methods: We reviewed medical literature using the PubMed database and present a case of aortic thrombosis due to a hypercoagulable state related to sigmoid colon adenocarcinoma. Results: Of the 18 patients from 14 articles included in this study, 13 received simple anticoagulation as a primary treatment (anticoagulation group), while 5 underwent surgical treatment (surgical treatment group). Recurrence or exacerbation of embolism was found in 2 (15.4%) of the 13 patients and in 1 (20.0%) of the 5 patients (P = 1.0). Major complications were observed in 1 (7.7%) of the patients in the anticoagulation group and in 1 (20.0%) of the 5 patients in the surgical treatment group (P = .49). No significant differences between the groups were found. Conclusions: A simple anticoagulation therapy may be as effective as surgical treatment in patients with aortic thrombosis associated with malignancy. [ABSTRACT FROM AUTHOR]

It is well known that the resistance to liquefaction of a saturated sand decreases sharply when it has been presheared, either cyclically or quasi statically, beyond a threshold value. The possible mechanism is discussed in light of recent findings on the microstructural anisotropy developed in preshearing (induced anisotropy). A columnlike structure, through which applied stress is mainly transmitted, grows parallel to the major principal stress direction in the strain hardening process. Voids, randomly distributed at first, are also connected in series between the columnlike structures. The anisotropic structure can carry the increasing stress as long as the major stress is applied parallel to the elongation direction of the structure. However, it becomes extremely unstable when the major stress is rotated. The excess pore-water pressure increases markedly under undrained cyclic loading, particularly when the connected voids are stressed perpendicular to their elongation direction. This is the reason why once liquefied sand sharply loses liquefaction resistance in a subsequent reliquefaction test.

Removal of heavy metals from wastewater is of special concern due to the persistence of heavy metals in the environment. The industrial discharge of heavy metals adversely affects soil and water resources, aquatic organisms, and ecosystem integrity. In addition, high concentrations of heavy metals are detected in solid waste landfill leachate in many developing countries due to non-segregated waste dumping. At present, various kinds of adsorbents such as activated carbon, biomass resources, geomaterials, and industrial waste products are used to treat heavy metal-contaminated water. However, the use of construction and demolition waste (CDW) and its recycled materials to treat heavy metal-contaminated water has not been fully examined. Because the generation of CDW is increasing due to rapid urbanization and a high demand for construction, the wise use of CDW and its recycled materials is necessary. This paper reviews journal articles published from 2004 to 2016 that studied the applicability of low-cost CDW adsorbents to remove heavy metals from wastewater. In particular, it summarizes results on using CDW and recycled materials such as cement, concrete, and brick compared to those from various other adsorbents such as biosorbents, geomaterials, and their industrial products. The potential applicability of CDW and its recycled materials as heavy-metal adsorbents was examined based on a comparison table listing material properties, test conditions, and measured adsorption properties. [ABSTRACT FROM AUTHOR]