37 research outputs found
Membrane hybrid systems in wastewater treatment
University of Technology Sydney. Faculty of Engineering and Information Technology.The production of fresh water and the disposal of wastewater are the major challenges for the last few decades. Reverse osmosis (RO) membrane plants are extensively used for industrial water purification. The large quantities of concentrate generated by RO plant have a disposal issue especially when the plant is located inland. Due to high disposal costs, there is need to reuse. RO reject concentrate is being increasingly processed to recover additional potable water. To achieve higher recoveries alternate processes are used.
Reverse osmosis concentrate (ROC) produced from water reclamation plant can threaten the environment, if it is not appropriately treated before discharge. Membrane bioreactor (MBR) is an attractive technology. Membrane bioreactor is an efficient, cost-effective and reliable treatment system to produce high-quality water from wastewater. This study examined the use of MBR with and without activated carbon such as granular activated carbon (GAC) or powdered activated carbon (PAC) for further treating wastewater and removal of organic micro-pollutants.
Fouling is an important and inevitable phenomenon in MBR. Lower membrane fouling implies more production of water, less cleaning of the membrane, long-term operation and longer membrane life, therefore, reducing operational and capital costs. Fouling can not fully reversed in MBR by physical cleaning alone. However, the combination of physical cleaning and chemical cleaning could almost fully restore the activity of the membrane. Thus, in this study, chemical cleaning in MBR was studied and the performance was compared with that of membrane adsorption hybrid system (MAHS). Synthetic wastewater was used in this study.
The composition of this wastewater was similar to reverse osmosis concentrate (ROC) from a wastewater reclamation plant. The influence of filtration flux and chemical cleaning was studied. The cleaning chemicals such as sodium hypochlorite (NaOCl) and nitric oxide (NO) was experimentally evaluated. Low concentration nitric oxide (NO) reduced the growth of biofilms in an MBR system. NO treatment could delay the formation of new biofilm on the membrane. NO also had the superiority over the traditionally used sodium hypochlorite (NaOCl) for backwashing as the later may have an adverse effect on the activated sludge and environment. NO treatment resulted in the reduction of the relative abundances of bacterial communities while might be encouraged in other bacterial communities.
⢠Submerged membrane adsorption hybrid system with granular activated carbon (GAC)
In this study, the effect of GAC on fouling reduction was studied in submerged MBR. The addition of GAC into the MBR system deferred TMP development. This is because of the mechanical scouring effect by GAC as well as by the pre-adsorption of organics before reaching the membrane surface. Also, it was observed that the addition of GAC in MBR system can effective for removing DOC by 94% throughout the experiment period for 120 days. These results further showed that the addition of GAC helped to reduce organic fouling.
⢠Membrane adsorption Bioreactor hybrid system
The operation of MBR resulted in the sudden rise of trans-membrane pressure (TMP). The sudden development of TMP was minimized by introducing activated carbon such as granular activated carbon (GAC) and powdered activated carbon (PAC) in MBR as a suspended medium. The incorporation of GAC and PAC prevented sudden TMP increase and also helped to remove an additional amount of dissolved organic matter.
⢠Submerged membrane adsorption hybrid system with powered activated carbon (PAC)
A detailed study was made with the real reverse osmosis concentrate (ROC) from a wastewater reclamation plant. Biologically activated carbon uptakes the soluble organics, therefore MBR-PAC hybrid system showed the superior removal of organic matter in this study. After the addition of PAC into the reactor, total organic carbon (TOC) removal increased sharply and went up to 91 %. The recovery of TOC removal was due to the adsorption of organic on PAC initially and then by bioadsorption. The addition of PAC was mostly responsible for the improved filtration performance in the MBR system by modifying the sludge characteristics and the cake layer on the membrane surface. Thus, the addition of PAC in the MBR led to a superior organic removal by a combination of bio flocculation and adsorption phenomena.
⢠Biofilter
Many wastewater treatment plants use MBR as their biological treatment step. MBR cannot remove persisting organic pollutants. Thus, in this study, the performance of granular activated carbon (GAC) biofilter and membrane adsorption hybrid system (MAHS) was evaluated for its ability to reduce effluent organic matter from MBR effluent collected from a decentralized MBR plant treating domestic wastewater. The up-flow biofilter column was packed with GAC to a height of 10 cm and 40 cm. The column was operated at a low velocity of 1.79 and 3.58 m/h and resulted in a high removal of dissolved organic carbon (DOC).
The MBR effluent consisted of eleven pharmaceuticals and personal care products (PPCPs). After a post-treatment of MF membrane-GAC adsorption hybrid system (MAHS), most of the micro pollutants were removed except for three compounds with very low concentrations. However, bisphenol A was found at the concentration of 316 ng/L at the end of the experiment
Constructing a Knowledge-Based Database for Dermatological Integrative Medical Information
Recently, overuse of steroids and immunosuppressive drugs has produced incurable dermatological health problems. Traditional medical approaches have been studied for alternative solutions. However,
accessing relevant information is difficult given the differences in information for western medicine (WM) and traditional medicine (TM). Therefore, an integrated medical information infrastructure must be utilized to bridge western and traditional treatments. In this study, WM and TM information was collected based on literature searches and information from internet databases on dermatological issues. Additionally, definitions for unified terminology and disease categorization based on individual cases were generated. Also a searchable database system was established that may be a possible model system for integrating both WM and TM medical information on dermatological conditions. Such a system will yield benefits for researchers and facilitate the best possible medical solutions for patients. The DIMI is freely available online
Artificialâintelligenceâdriven discovery of prognostic biomarker for sarcopenia
Abstract Background Sarcopenia is defined as muscle wasting, characterized by a progressive loss of muscle mass and function due to ageing. Diagnosis of sarcopenia typically involves both muscle imaging and the physical performance of people exhibiting signs of muscle weakness. Despite its worldwide prevalence, a molecular method for accurately diagnosing sarcopenia has not been established. Methods We develop an artificial intelligence (AI) diagnosis model of sarcopenia using a published transcriptome dataset comprising patients from multiple ethnicities. For the AI model for sarcopenia diagnosis, we use a transcriptome database comprising 17Â 339 genes from 118 subjects. Among the 17Â 339 genes, we select 27 features as the model inputs. For feature selection, we use a random forest, extreme gradient boosting and adaptive boosting. Using the top 27 features, we propose a fourâlayer deep neural network, named DSnetâv1, for sarcopenia diagnosis. Results Among isolated testing datasets, DSnetâv1 provides high sensitivity (100%), specificity (94.12%), accuracy (95.83%), balanced accuracy (97.06%) and area under receiver operating characteristics (0.99). To extend the number of patient data, we develop a web application (http://sarcopeniaAI.ml/), where the model can be accessed unrestrictedly to diagnose sarcopenia if the transcriptome is available. A focused analysis of the top 27 genes for their differential or coâexpression with other genes implied the potential existence of raceâspecific factors for sarcopenia, suggesting the possibility of identifying causal factors of sarcopenia when a more extended dataset is provided. Conclusions Our new AI model, DSnetâv1, accurately diagnoses sarcopenia and is currently available publicly to assist healthcare providers in diagnosing and treating sarcopenia
Bio-printing of aligned GelMa-based cell-laden structure for muscle tissue regeneration
Volumetric muscle loss (VML) is associated with a severe loss of muscle tissue that overwhelms the regenerative potential of skeletal muscles. Tissue engineering has shown promise for the treatment of VML injuries, as evidenced by various preclinical trials. The present study describes the fabrication of a cell-laden GelMa muscle construct using an in situ crosslinking (ISC) strategy to improve muscle functionality. To obtain optimal biophysical properties of the muscle construct, two UV exposure sources, UV exposure dose, and wall shear stress were evaluated using C2C12 myoblasts. Additionally, the ISC system showed a significantly higher degree of uniaxial alignment and myogenesis compared to the conventional crosslinking strategy (post-crosslinking). To evaluate the in vivo regenerative potential, muscle constructs laden with human adipose stem cells were used. The VML defect group implanted with the bio-printed muscle construct showed significant restoration of functionality and muscular volume. The data presented in this study suggest that stem cell-based therapies combined with the modified bioprinting process could potentially be effective against VML injuries
Topical Application of Galgeunhwanggeumhwangryeon-Tang Recovers Skin-Lipid Barrier and Ameliorates Inflammation via Filaggrin-Thymic Stromal Lymphopoietin-Interleukin 4 Pathway
Background and objectives: The purpose of this study was to confirm the effect of Galgeunhwanggeumhwangryeon-tang (GGRT) on the skin barrier integrity and inflammation in an atopic dermatitis-like animal model. Materials and Methods: The model was established using lipid barrier elimination (LBE) in BALB/c mice. Ceramide 3B, a control drug, and GGRT were applied to the skin of LBE mice. Gross observation and histological examination were combined with measurement of skin score, trans-epidermal water loss, and pH. The expression of filaggrin, kallikrein-related peptidase 7 (KLK7), protease-activated receptor-2 (PAR-2), thymic stromal lymphopoietin (TSLP), and interleukin 4 (IL-4) was examined. Results: The effect of GGRT on atopic dermatitis was estimated in silico using two individual gene sets of human atopic dermatitis. In animal experiments, GGRT treatment reduced atopic dermatitis-like symptoms, as confirmed via gross and histological observations, skin score, pH change, and trans-epidermal water loss. The expression level of filaggrin increased in the skin of GGRT-treated mice compared to that in the LBE group. The expression levels of KLK7, PAR2, TSLP, and IL-4 were decreased in GGRT-treated mice skin compared to those in LBE mice. Conclusions: We demonstrated that GGRT restored the skin barrier and reduced inflammatory reactions in a murine model of atopic dermatitis