Characterization of landfill leach ate from municipal solid wastes landfills in Sri Lanka

Open dumping of municipal solid waste (MSW) is the most common way of handling solid waste in Sri Lanka due to high cost involved with advanced technologies for landfilling, lack of technical capacity, lack of know-how to manage landfill sites, and so on. Landfill leachate generated from the MSW landfill sites must be treated before dispose into the environment as it creates many social and environmental problems. Characterization of landfill leachate is important to identify the most critical pollutants present in the leachate and thereby to introduce suitable and applicable treatment technologies such as in-situ permeable reactive barrier technologies for contaminant remediation. Therefore, the objective of this research is to characterize landfill leachate collected from several MSW landfills in Sri Lanka. The leachate samples were collected from 12 landfill sites located in Matale, Hambantota, Kataragama, Bandaragama, Kolonnawa, Gampola, Gohagoda, Wennappuwa, Rathnapura, Negombo, Galle, and Matara. For the collected samples, general water quality parameters (pH, EC, DO, ORP, and SS), organic pollutants (BOD5, COD, TOC, IC, TN, TP), typical anions and cations (Cl-, SO42-, NH4+, K+, Mg2+, Ca2+, etc), and heavy metals (Cr, Mn, Fe, Se, Pb, etc) were measured. The results showed that most of the pollutants (F-, Cl-, PO43-, NH4+, Fe, Se, Pb, BOD5, and COD) exceeded the maximum tolerance limits in Sri Lankan Standards. It was found that the BOD5/COD ratio ranged from 0.01 to 0.6 for the most samples and the highest value of 0.6 was observed in the Kolonnawa sample. Measured EC values for all samples were high and varied ranging from 4.5 to 38.3 mS/cm, indicating the biological treatment system alone would not be effective in reducing the pollutants especially for heavy metals. The results of this study will be used in developing site specific remediation technologies in landfill leachate treatment

Cyclooxygenase 2 and Prostaglandin E2 are not Involved in N-Nitrosodiethylamine-Initiated Early Rat Hepatocarcinogenesis

The present study was undertaken to investigate the effect of dietary supplementation with nimesulide or eugenol on N-nitrosodiethylamine (DEN)-initiated early hepatocarcinogenesis in F344 male rats. Both compounds did not alter the expression of cytochrome P450 (CYP) 2E1, the enzyme that plays a major role in the activation of DEN to genotoxic products; however, nimesulide induced the expression of CYP1A1. Western blot analysis revealed that COX-1 and COX-2 protein expressions were not modulated by DEN compared with normal controls. Furthermore, post-initiation feeding with nimesulide or eugenol did not modulate COX-2 protein expression in normal or DEN-treated rats, whereas eugenol significantly increased the liver prostaglandin E2 (PGE2) levels of DEN-injected animals compared with the DEN controls. Ultimately, nimesulide or eugenol did not modify DEN-induced hepatocarcinogenesis as evidenced by insignificant changes in the number and size of preneoplastic placental glutathione S-transferase (GST-P) positive liver foci compared with the DEN controls. These results suggest that COX-2, as well as prostaglandin E2, may play no role in the post-initiation development of DEN-induced rat hepatocarcinogenesis at an early stage

Prohibitins Are Required for Cancer Cell Proliferation and Adhesion

Prohibitin 1 (PHB1) is a highly conserved protein that together with its homologue prohibitin 2 (PHB2) mainly localizes to the inner mitochondrial membrane. Although it was originally identified by its ability to inhibit G1/S progression in human fibroblasts, its role as tumor suppressor is debated. To determine the function of prohibitins in maintaining cell homeostasis, we generated cancer cell lines expressing prohibitin-directed shRNAs. We show that prohibitin proteins are necessary for the proliferation of cancer cells. Down-regulation of prohibitin expression drastically reduced the rate of cell division. Furthermore, mitochondrial morphology was not affected, but loss of prohibitins did lead to the degradation of the fusion protein OPA1 and, in certain cancer cell lines, to a reduced capability to exhibit anchorage-independent growth. These cancer cells also exhibited reduced adhesion to the extracellular matrix. Taken together, these observations suggest prohibitins play a crucial role in adhesion processes in the cell and thereby sustaining cancer cell propagation and survival

Determination of relevance between surface free energy and adsorption capacity of cement particles

ABSTRACT The compatibility between superplasticizer and cement was influenced by the adsorption capacity of cement particles. This study investigated the relevance between the adsorption capability and surface free energy. Adsorption capacity and surface free energy of both sulphoaluminate cement and portland cement were measured. The adsorption capacity of cement particles was measured by ultraviolet spectrophotometry. The test showed that particles of sulphoaluminate cement adsorbed more molecules of superplasticizer than portland cement particles. The weight of superplasticizer adsorbed by 2g of sulphoaluminate cement and portland cement were 0.28mg and 0.159mg respectively. Surface free energy of cement particles was calculated by contact angle and the contact angles were determined by the thin-layer wicking technique and washburn equation which is theoretical basis of thin-layer wiching technique presented by Chibowski E. The sulphoaluminate cement, portland cement's surface free energy were 51.46 mJ·m-2 and 49.36 mJ·m-2 respectively. The results showed that the higher adsorption capacity of particles was usual accompanied by higher surface free energy. The fluidity of cement paste was influenced by the adsorption capacity of cement particles because the more molecules of superplasticizer was adsorbed by cement particles there were lacking superplasticizer in the paste. The macro-behaviour of higher adsorption capacity is that the cement paste need more superplasticizer to reach the needed fluidity

Experimental investigation of innovative hybrid composite girders with GFRP and CFRP

This paper focuses on flexural behavior of innovative hybrid I-shaped girders consisting of Glass Fiber Reinforced Plastics and Carbon Fiber Reinforced Plastics. The experimental investigation revealed that the delamination at the interface of glass and carbon fibers in the compressive flange caused a sudden failure and lead to smaller loading capacity than the expected in the case of girders with smaller flange width. In the case of wider flange width, the local buckling of flange in compressive side was observed. It was experimentally found that the appropriate installation of web stiffeners is an effective way to prevent the local buckling of wide flange sections but that FRP materials cannot also exhibit their intrinsic material strength due to the delamination. In order to utilize the materials properties of FRP effectively, it is recommended that further study is conducted with a section having neutral axis towards the upper side of the section

Orbital septum attachment sites on the levator aponeurosis in Asians and whites

Purpose: To characterize the attachment site of the orbital septum on the levator aponeurosis and the anatomic level of the inferior end of the preaponeurotic fat pad, both in Asians and whites. Materials and Methods: Full-thickness sagittal sections of upper eyelids, fixed in 10% buffered formalin, were microscopically examined in 18 postmortem upper eyelids of 10 Asian cadavers (mean death age, 78 years; age range, 68–89 years) and 11 postmortem upper eyelids of 7 whites (mean death age, 88 years; age range, 78–101 years). We measured the distance from the superior tarsal border to the attachment site of the orbital septum on the levator aponeurosis based on the position of the distal end of the anterior layer of the levator aponeurosis. In addition, the position of the inferior end of the preaponeurotic fat pad was simultaneously measured from the superior tarsal border. Results: The average distance from the superior tarsal border to the distal end of the anterior layer of the levator aponeurosis was 4.44 mm in Asians and 3.71 mm in whites (p = 0.412). The average distance from the superior tarsal plate border to the preaponeurotic fat pad was 1.90 mm in Asians and 3.17 mm in whites (p = 0.173). Conclusions: The distance from the orbital septum attachment site on the levator aponeurosis to the superior tarsal border is similar in Asians and whites. However, there is some tendency, although not statistically significant, to a lower extension of the preaponeurotic fat pad in Asians.Hirohiko Kakizaki, Dinesh Selv, Ken Asamoto, Takashi Nakano and Igal Leibovitc

Orbital Septum Attachment on the Levator Aponeurosis in Asians. In Vivo and Cadaver Study

Copyright © 2009 American Academy of Ophthalmology Published by Elsevier Inc. Original articlePurpose To examine the anatomic relationships between the preaponeurotic fat pad, orbital septum, and the distal end of the anterior layer of the levator aponeurosis (DEALLA) in relation to the superior tarsal plate border. Design Prospective, clinical case series and experimental anatomic study. Participants Twenty-two upper eyelids in 11 Asian patients (average age, 76.5 years) and 10 postmortem upper eyelid specimens of 7 Asians (average age, 81 years). Methods The relationships between the orbital septum, DEALLA, preaponeurotic fat pad, and the superior tarsal plate border were examined in vivo, during upper blepharoplasty. In cadavers, the orbital septum was exposed and excised from the DEALLA, and the distance from the superior tarsal plate border to the DEALLA was measured at 3 points: the center of the palpebral width, and 2 points located 7 mm medial and lateral to the center. Main Outcome Measures The anatomic relationships of the orbital septum, DEALLA, and the preaponeurotic fat pad with the superior tarsal plate border. Results In vivo, the DEALLA was always located above the superior tarsal plate border, and the lower margin of the preaponeurotic fat was always positioned below the DEALLA and around the superior tarsal plate border. The lateral preaponeurotic fat in 4 eyelids showed extension beyond the superior tarsal border. In cadavers, the average distance from the superior tarsal plate border to the DEALLA was 3.7 mm centrally, 3.0 mm medially, and 0.9 mm laterally. In 3 specimens, the confluent part of the orbital septum and the levator aponeurosis reached the tarsus in the lateral area. Conclusions Orbital septum attachment on the levator aponeurosis in Asians seems to be situated above the superior tarsal plate border in vivo, but the preaponeurotic fat extends beyond the DEALLA, sometimes reaching the tarsal plate. In some cadavers, the confluent part was found to be situated on the tarsus laterally.Hirohiko Kakizaki, Igal Leibovitch, Dinesh Selva, Ken Asamoto and Takashi Nakan