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To evaluate the effectiveness of the Enhanced Primary Healthcare (EnPHC) interventions on process of care and intermediate clinical outcomes among type 2 diabetes patients. This was a quasi-experimental controlled study conducted in 20 intervention and 20 control public primary care clinics in Malaysia from November 2016 to June 2019. Type 2 diabetes patients aged 30 years and above were selected via systematic random sampling. Outcomes include process of care and intermediate clinical outcomes. Difference-in-differences analyses was conducted. We reviewed 12,017 medical records of patients with type 2 diabetes. Seven process of care measures improved: HbA1c tests (odds ratio (OR) 3.31, 95% CI 2.13, 5.13); lipid test (OR 4.59, 95% CI 2.64, 7.97), LDL (OR 4.33, 95% CI 2.16, 8.70), and urine albumin (OR 1.99, 95% CI 1.12, 3.55) tests; BMI measured (OR 15.80, 95% CI 4.78, 52.24); cardiovascular risk assessment (OR 174.65, 95% CI 16.84, 1810.80); and exercise counselling (OR 1.18, 95% CI 1.04, 1.33). We found no statistically significant changes in intermediate clinical outcomes (i.e. HbA1c, LDL, HDL and BP control). EnPHC interventions was successful in enhancing the quality of care, in terms of process of care, by changing healthcare providers behaviour. • EnPHC is a multifaceted intervention that exists as an integrated care mode. • It improved seven out of fourteen processes of care in diabetes management. • Intermediate clinical outcomes such as HbA1c, LDL, and HDL were also measured. • Targets were met for three out of four outcomes, but they were not statistically significant. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2010.03.021 Byline: Yi Jing Chan, Mei Fong Chong, Chung Lim Law Abstract: The production of highly polluting palm oil mill effluent (POME) has resulted in serious environmental hazards. While anaerobic digestion is widely accepted as an effective method for the treatment of POME, anaerobic treatment of POME alone has difficulty meeting discharge limits due to the high organic strength of POME. Hence, subsequent post-treatment following aerobic treatment is vital to meet the discharge limits. The objective of the present study is to investigate the aerobic treatment of anaerobically digested POME by using a sequencing batch reactor (SBR). The SBR performance was assessed by measuring Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD) and Total Suspended Solids (TSS) removal as well as Sludge Volume Index (SVI). The operating pH and dissolved oxygen concentrations were found to be 8.25-9.14 and 1.5-6.4mg/L, respectively, throughout the experiment. The experimental results demonstrate that MLVSS, OLR and sludge loading rate (SLR) play a significant role in the organic removal efficiency of SBR systems and therefore, further investigation on these parameters was conducted to attain optimum SBR performance. Maximum COD (95-96%), BOD (97-98%) and TSS (98-99%) removal efficiencies were achieved at optimum OLR, SLR and MLVSS concentration ranges of 1.8-4.2kgCOD/m.sup.3 day, 2.5-4.6kgTSS/m.sup.3 day and 22,000-25,000mg/L, respectively. The effluent quality remained stable and complied with the discharge limit. At the same time, the sludge showed good settling properties with average SVI of 65. It is envisaged that the SBR process could complement the anaerobic treatment to produce final treated effluent which meets the discharge limit. Author Affiliation: School of Chemical and Environmental Engineering, Faculty of Engineering, The University of Nottingham Malaysia Campus, Jalan Broga 43500, Semenyih, Selangor, Malaysia Article History: Received 23 July 2009; Revised 10 March 2010; Accepted 26 March 2010

This paper reports a techno-economic assessment for industrial scale bio-flocculant production with okra as biomass feedstock. The sludge dewatering ability of the bio-flocculant was evaluated prior to economic analysis. Several optimisation strategies were investigated in order to lower the bio-flocculant production cost. The results showed that continuous mode microwave extraction was more economically beneficial than conventional extraction in batch and continuous modes. Sensitivity analysis revealed that the production cost was significantly affected by annual production and extract yield, and moderately influenced by raw material price. The optimised scheme for bio-flocculant production was continuous mode microwave extraction at 90° C, a residence time of 10 minutes, a water loading of 3.5 w/w and production rate of 220 tonnes per year. The economic assessment showed that the gross margin was positive, return on investment was in the expected range of 20 to 30% and payback time was within 5 years. [ABSTRACT FROM AUTHOR]

Bidirectional co-morbidity between migraine and depression has been observed. Mood disorders are associated with an increased risk of both migraine and irritable bowel syndrome (IBS). The aim of this study was to evaluate the risk of developing IBS in patients with migraine and to compare the risks between those with and without anxiety or depression. This research used the data contained in the National Health Insurance Research Database (NHIRD). A total of 2859 subjects with migraine and 5718 age-, sex-, hypertension-, diabetes-, mood disorder-matched controls were identified. Both cohorts excluded subjects with pre-existing catastrophic illness and IBS diagnosed before the index visit or within 30 days after the index visit. All individuals of both cohorts were tracked until either having the diagnosis of IBS, loss of follow-up, or IBS free up to 7 years. During the 7-year follow-up period, 8.4% of patients with migraine and 5.4% of control cohort developed IBS. Migraine is associated with an increased risk of developing IBS (HR = 1.58, 95% CI: 1.33–1.87). When separating the cohort into those with mood disorder and without it, migraine is a significant risk factor of IBS in patients without mood disorders, but not in patients with co-existed mood disorders. The findings of this study suggest that migraine is a risk factor of future IBS development for those without comorbid anxiety or depression. However, migraine does not contribute significantly additional risk to IBS development in patients with comorbid anxiety or depression. [ABSTRACT FROM AUTHOR]

Summary The airway epithelium develops into a tree-like structure via branching morphogenesis. Here, we show a critical role for localized differentiation of airway smooth muscle during epithelial bifurcation in the embryonic mouse lung. We found that during terminal bifurcation, changes in the geometry of nascent buds coincided with patterned smooth muscle differentiation. Evaluating spatiotemporal dynamics of α-smooth muscle actin (αSMA) in reporter mice revealed that αSMA-expressing cells appear at the basal surface of the future epithelial cleft prior to bifurcation and then increase in density as they wrap around the bifurcating bud. Disrupting this stereotyped pattern of smooth muscle differentiation prevents terminal bifurcation. Our results reveal stereotyped differentiation of airway smooth muscle adjacent to nascent epithelial buds and suggest that localized smooth muscle wrapping at the cleft site is required for terminal bifurcation during airway branching morphogenesis. [ABSTRACT FROM AUTHOR]

Abstract: The chemical and phase equilibrium is important to be computed simultaneously in lipid transesterification which occurs in a two-phase system. Such analysis is highly desired to ease the reactor design and optimization problems. The objective of this study is to conduct a thorough investigation on lipid transesterification in a continuous stirred tank reactor (CSTR) with the consideration of chemical phase equilibrium (CPE) via modeling and simulation analysis. The transesterification of canola oil with methanol to fatty acid methyl ester was considered in this study. The UNIQUAC thermodynamic model was used to investigate the liquid–liquid equilibrium (LLE) behavior of the six-component system formed during the biodiesel production. By comparing the LLE behavior between ternary and six-component systems, the data shows that six-component system gave a better representation of the main phase variation in the transesterification process. In addition, the CPE model developed in this study was verified by comparing the simulated results with the results obtained from the transesterification reaction experiments in CSTR. The results obtained from the CPE model analysis show that the proposed CPE model is adequate to be used for the description of simultaneous chemical reaction and phase equilibrium during the transesterifcation process at an acceptable accuracy. The CPE investigation shows that if an efficient reaction needs to be achieved, the CPE needs to be controlled to obtain higher concentration gradients between the two reacting phases. [Copyright &y& Elsevier]

Abstract: Thermophilic treatment of palm oil mill effluent (POME) was studied in a novel integrated anaerobic–aerobic bioreactor (IAAB). The IAAB was subjected to a program of steady-state operation over a range of organic loading rate (OLR)s, up to 30g COD/Lday in order to evaluate its treatment capacity. The thermophilic IAAB achieved high chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) removal efficiencies of more than 99% for OLR up to 18.5g COD/Lday. High methane yield of 0.32LCH4 (STP)/g CODremoved with compliance of the final treated effluent to the discharge limit were achieved. This is higher than that of the mesophilic system due to the higher maximum specific growth rate (μ max) of the thermophilic microorganisms. Besides, coupling the model of Grau second order model (anaerobic system) with the model of Monod (aerobic system) will completely define the IAAB system. [Copyright &y& Elsevier]

Abstract: Palm oil mill effluent (POME) with average chemical oxygen demand (COD) and biochemical oxygen demand (BOD) of 70,000 and 30,000mg/L, respectively, can cause serious environmental hazards if discharged untreated. There are conventional palm oil mill effluent (POME) treatment systems that require large footprint, long HRT and fail to meet the Malaysian Department of Environment (DOE) discharge limit. Hence, the current research is aimed to design a novel integrated anaerobic–aerobic bioreactor (IAAB) for POME treatment in order to overcome these shortcomings of the conventional system. IAAB is a new bioreactor configuration which integrates anaerobic and aerobic digestion in one reactor. The overall removal efficiencies in steady state condition in terms of chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) were more than 99% at the organic loading rate (OLR) of 10.5g COD/Lday with methane yield of 0.24LCH4/g COD removed. The effluent quality remained stable (BOD<70mg/L) and complied with the discharge limit (BOD<100mg/L). Overall, the IAAB system exhibited good stability and pH adjustment was unnecessary. The results show that the IAAB achieves higher performance in terms of organic removal efficiency and methane yield at higher OLR and shorter HRT as compared to the conventional system. Further evaluations of its long-term performance are proposed for the subsequent study. [Copyright &y& Elsevier]

Abstract: Boron is extensively used in the ceramic industry for enhancing mechanical strength of the tiles. The discharge of boron containing wastewater to the environment causes severe pollution problems. Boron is also dangerous for human consumption and causes organisms'' reproductive impediments if the safe intake level is exceeded. Current methods to remove boron include ion-exchange, membrane filtration, precipitation–coagulation, biological and chemical treatment. These methods are costly to remove boron from the wastewater and hence infeasible for industrial wastewater treatment. In the present research, adsorption–flocculation mechanism is proposed for boron removal from ceramic wastewater by using Palm Oil Mill Boiler (POMB) bottom ash and long chain polymer or flocculant. Ceramic wastewater is turbid and milky in color which contains 15mg/L of boron and 2000mg/L of suspended solids. The optimum operating conditions for boron adsorption on POMB bottom ash and flocculation using polymer were investigated in the present research. Adsorption isotherm of boron on bottom ash was also investigated to evaluate the adsorption capacity. Adsorption isotherm modeling was conducted based on Langmuir and Freundlich isotherms. The results show that coarse POMB bottom ash with particle size larger than 2mm is a suitable adsorbent where boron is removed up to 80% under the optimum conditions (pH=8.0, dosage=40g bottom ash/300ml wastewater, residence time=1h). The results also show that KP 1200 B cationic polymer is effective in flocculating the suspended solids while AP 120 C anionic polymer is effective in flocculating the bottom ash. The combined cationic and anionic polymers are able to clarify the ceramic wastewater under the optimum conditions (dosage of KP 1200 B cationic polymer=100mg/L, dosage of AP 120 C anionic polymer=50mg/L, mixing speed=200rpm). Under the optimum operating conditions, the boron and suspended solids concentration of the treated wastewater were reduced to 3mg/L and 5mg/L respectively, satisfying the discharge requirement by Malaysia Department of Environment (DOE). The modeling study shows that the adsorption isotherm of boron onto POMB bottom ash conformed to the Freundlich Isotherm. The proposed method is suitable for boron removal in ceramic wastewater especially in regions where POMB bottom ash is abundant. [Copyright &y& Elsevier]

The aim of this study was to investigate factors influencing nursing students' intention to use a simulated web-application 'Integrated Nursing Education System' for practicing electronic health documentation. The cross-sectional study was conducted at a Malaysian University that provides undergraduate nursing degree program. A total of 133 undergraduate nursing students in their year 2 to year 4 of the program were recruited. They had accessed the simulated web-application as part of the teaching-learning activities during the academic year 2016/2017. Technology Acceptance Model was used to guide the study. Validated questionnaires were used to measure the students' perceived ease of use, perceived usefulness, attitudes and intention to use the application. Data collection was done at the end of the semester. Data analysis was done using SPSS (19.0) and AMOS (23.0). Perceived usefulness was the most influential factor of the students' intention to use the simulated web-application. Perceived ease of use influenced their perceived usefulness significantly. Nurse educators should explain the usefulness of the simulated web-application before assigning students to access it to practice electronic health documentation. The availability of a stable internet access and IT support is important to influence students' perceived ease of use and intention to use the application. • Perceived usefulness was the most influential factor of students' intention to use. • Perceived ease of use influenced their perceived usefulness significantly. • Nurse educators should explain the usefulness of the web-application to students. • The availability of a stable internet access and IT support is important. [ABSTRACT FROM AUTHOR]

Patients with severe asthma that remain uncontrolled incur significant medical burden and healthcare costs. Severe asthma is a heterogeneous airway disorder with complex pathophysiological mechanisms which can be broadly divided into type 2 (T2)-high and T2-low inflammatory pathways. Recent advances in asthma therapeutics with the advent of biologics have heralded an era of promising targeted therapy in this group of patients. The current available biologics, including anti-IgE mAb, anti-IL-5/IL-5R mAb and anti-IL-4Rα mAb, mainly target patients with an asthma endotype characterised by T2-high inflammation. While they have delivered positive outcomes in terms of reduction in exacerbations, improving lung function and quality of life, as well as reducing the dependence on oral corticosteroids, they have not functioned as the "panacea" as a significant proportion of patients do not respond completely to these targeted therapies. In addition, there is a lack of markers that can predict treatment response and clinicians are guided only by subjective asthma symptom scores. Suboptimal treatment response is common for individual patients. There has also been a dearth of effective targeted therapy for patients with T2-low asthma and treatment options remain limited for these patients. There is a pipeline of newer biologics targeting cytokines that operate at the interface between innate and adaptive immunity (e.g. IL-17A, thymic stromal lymphopoietin (TSLP), IL-25, IL-33, IL-32 and IL-36γ) with potential of modifying and reducing the severity of asthma. This commentary provides an overview of treatment with the current biologics and highlights the limitations, challenges and unmet needs in clinical management. We also summarise up-and-coming potential targets and therapeutic biologics for severe asthma. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editors discuss various reports within the issue on topics including the development of advanced waste treatment technologies, boron removal using electrocoagulation, and work on process integration.

Flocculation is an essential phenomenon in industrial wastewater treatment. Inorganic coagulants (salts of multivalent metals) are being commonly used due to its low cost and ease of use. However, their application is constrained with low flocculating efficiency and the presence of residue metal concentration in the treated water. Organic polymeric flocculants are widely used nowadays due to its remarkable ability to flocculate efficiently with low dosage. However, its application is associated with lack of biodegradability and dispersion of monomers residue in water that may represent a health hazard. Therefore, biopolymers based flocculants have been attracting wide interest of researchers because they have the advantages of biodegradability and environmental friendly. But, natural flocculants are needed in large dosage due to its moderate flocculating efficiency and shorter shelf life. Thus, in order to combine the best properties of both, synthetic polymers are grafted onto the backbone of natural polymers to obtain tailor-made grafted flocculants. This paper gives an overview of the development of different types of flocculants that were being investigated for treatment of industrial wastewater. Furthermore, their flocculation performance will be reviewed and the flocculation mechanism will be discussed. [ABSTRACT FROM AUTHOR]

Abstract: Objective:: To evaluate the use of the Laryngeal Mask Airway (LMA), the oesophageal-tracheal combitube (ETC) and the tracheal tube (TT) by medical students, with a view to recommend changes to the medical school curriculum. Methods:: A prospective cohort study of 93 third-year medical students were taught the use of LMA, ETC and TT on manikins and had their skills tested at 0 and 6 months. Results:: Overall, LMA insertion was the fastest technique with a mean time taken for successful insertion of 32.2s, compared to that for ETC (55.0s, P = 0.000) and TT (71.5s, P = 0.000). There was a significant delay in the time taken for insertion at 6 months for all three devices: 13.5s for the LMA (P = 0.000), 29.6s for the ETC (P = 0.000) and 31.8s for the TT (P = 0.001). Both the ETC and the TT had a significantly lower first-attempt success rate at 6 months (ETC: 91% versus 63%, P = 0.000 and TT: 80% versus 55%, P = 0.003) but not the LMA (96% versus 92%, P = 0.549). At 6 months, the overall success rate was 99% for the LMA, 100% for the ETC and 93% for the TT. Complication rate was higher for the ETC (9% versus 46%, P = 0.000) and the TT (38% versus 78%, P = 0.005) but not for the LMA (3% versus 10%, P = 0.688). Conclusions:: The use of the TT is difficult and the skills acquired by the medical students deteriorate significantly over time. The LMA and the ETC seem to have an advantage over the TT in that they are more easily learnt and the skills better retained. It is recommended that these alternative devices be included in the medical school curriculum for airway management. [Copyright &y& Elsevier]

The development of a blood-stage malaria vaccine has largely focused on the subunit approach. However, the limited success of this strategy, mainly due to antigenic polymorphism and the failure to maintain potent parasite-specific immune responses, indicates that other approaches must be considered. Whole parasite (WP) vaccines offer many advantages over sub-units; they represent every antigen on the organism, thus limiting the effects of antigenic polymorphism, and similarly they compensate for individual Immune-Response (Ir) gene-regulated non-responsiveness to any particular antigen. From a development perspective, they negate the need to identify and compare the relative efficacies of individual candidate antigens. WP vaccines induce protective immunity that is largely cell-mediated. However, WP blood-stage vaccines present a number of challenges for the development pathway. Key issues are cryopreservation and storage and the possible induction of antibodies against red blood cell surface antigens, even if the parasites are grown in blood group O, Rh negative blood. Here, we used a novel adaptation of an immunomagnetic method from STEMCELL™ Technologies to remove the red cell membranes from human red blood cells parasitized with P. falciparum. We then used these antigens to construct liposomes which were modified to present mannose on their membrane to target the liposome to antigen presenting cells. We then compared the immunogenicity of freshly prepared and lyophilized liposome vaccines. Following vaccination of mice, liposomes induced significantly lower antibody responses to human red cells but potent strain- and species-transcending cell-mediated immune responses to parasite antigens. These data support transitioning the P. falciparum liposomal vaccine into clinical studies. [ABSTRACT FROM AUTHOR]

Summary: Angiogenesis, the process by which new blood vessels arise from preexisting ones, is critical for embryonic development and is an integral part of many disease processes. Recent studies have provided detailed information on how angiogenic sprouts initiate, elongate, and branch, but less is known about how these processes cease. Here, we show that S1PR1, a receptor for the blood-borne bioactive lipid sphingosine-1-phosphate (S1P), is critical for inhibition of angiogenesis and acquisition of vascular stability. Loss of S1PR1 leads to increased endothelial cell sprouting and the formation of ectopic vessel branches. Conversely, S1PR1 signaling inhibits angiogenic sprouting and enhances cell-to-cell adhesion. This correlates with inhibition of vascular endothelial growth factor-A (VEGF-A)-induced signaling and stabilization of vascular endothelial (VE)-cadherin localization at endothelial junctions. Our data suggest that S1PR1 signaling acts as a vascular-intrinsic stabilization mechanism, protecting developing blood vessels against aberrant angiogenic responses. [Copyright &y& Elsevier]

Abstract: Biodiesel is commonly produced from lipid feedstock, animal fats and waste cooking oil by transesterification reaction. Considering the depletion of fossil fuel, biodiesel is gaining more attention as a renewable and environmental friendly fuel. The rapid growth of biodiesel industry thereafter has raised concerns to many existing commercial biodiesel enterprises. The major issues like feedstock flexibility, yield productivity and environmental impact are always the challenges to the continuous growth of conventional biodiesel processing technology. The processing of biodiesel is greatly hinged on the rich scientific background and technology development for better process advancement. The present paper reviews various concerns raised from the commercial biodiesel processing technology. It also addresses some innovative process intensification (PI) technologies, which likely bring appropriate technological improvement for biodiesel production. [Copyright &y& Elsevier]

Abstract: Petunia (Petunia × hybrida Hort. Vilm.-Andr.) plants were transformed by Agrobacterium with antisense BoACS1 (broccoli ACC synthase) and antisense BoACO1 (broccoli ACC oxidase) coding sequences of enzymes involved in biosynthesis of ethylene in broccoli plants. The integration of these genes with an antisense orientation was verified by PCR analyses of kanamycin-resistant regenerants. The expression of transgenes and endogenous genes was further confirmed by RT-PCR analysis. Production of ethylene in shoot tissues was reduced among most transgenic plants. Flowers of transformants, especially excised flowers, generally remained fresh longer than those of untransformed controls. The delayed flower senescence was more pronounced with the antisense BoACO1 than the antisense BoACS1. Transgenic tissues were, nevertheless, still responsive to ethylene. We conclude that the antisense BoACO1 gene from Brassica oleracea is able to reduce ethylene biosynthesis and delay flower senescence of Petunia hybrida more efficiently than the antisense BoACS1 gene. [Copyright &y& Elsevier]

Three main parameters of palm oil mill effluent (POME) i.e. biological oxygen demand (BOD), total suspended solids (TSS) and oil and grease (O&G), at high concentrations, have hindered efficient anaerobic digestion (AD) due to sludge flotation and scum formation. In this study, Moringa Oleifera extract was co-digested with POME to allow TSS and O&G to be coagulated and settled, and hence, an immobilisation media formed for better digestibility. Mono-digestion (POME, T1 and M. oleifera extract, T2, separately) served as control while co-digestion involved dosing 50 mL of M. oleifera extract (500 mg/L) into a fixed volume of POME (450 mL) at two feeding modes: daily, day 1 to day 30 (T3) and one-time, day 1 (T4). Treatments T1-T4 were conducted in an enclosed AD system for 30 days and the undesirable organic materials removal efficiencies i.e. BOD removal , TSS removal and O&G removal were compared. POME co-digestion, T4, showed an improved 92% TSS removal , 94% BOD removal and methane yield of 24.3 mL CH 4 /g COD removed. The results suggested that the nitrogen-fixing capabilities of anoxic microbial cells enhanced proliferation and growth encapsulated within the immobilisation media. Methanogen bacterial DNAs isolated from POME, granular sludge and anaerobically-treated POME were identified as Methanoculleus spp., Methanolinea spp. and Methanoculleus spp., respectively. Two-step complementary DNA (cDNA) and quantitative polymerase chain reaction (qPCR) confirmed the highest methanogen DNA concentration in T4. Therefore, the naturally occurring underutilised M. oleifera can be an organic coagulant for efficient POME co-digestion with an overall 69% and 59.5% higher methane yield and TSS removal than mono-digestion. Image 1 • Organic materials (TSS and O&G) are inhibitory during AD of POME for biogas. • Protein in Moringa oleifera extract shows coagulating effect in co-digestion of POME. • POME pH is maintained after M. oleifera addition for effective coagulation. • 500 mg/L diluted extract, fed once, perform >90% organics and solids removal. • POME- M. oleifera co-digestion accommodate highest methanogen species via cDNA-qPCR. [ABSTRACT FROM AUTHOR]

Palm oil mill effluent has been extensively researched via three different technologies, namely chemical, physicochemical and biological treatment methods. Biological treatment by anaerobic and aerobic means is currently the most commonly used method for palm oil mill effluent. However, the greatest challenge posed by them is the inconsistent biological oxygen demand of 20 mg/L for the final treated effluent. Large amount of investment for additional polishing plant prior to the final discharge has been utilised intentionally to further reduce the biochemical oxygen demand values, but the problem remains unresolved. The performance of current palm oil mill effluent treatment system deployed by the industry was evaluated by comparing two different types of anaerobic treatments: open ponding and covered lagoon systems (with hydraulic and gas mixing). The covered lagoon with hydraulic mixing achieved the highest chemical oxygen demand, total suspended solids, total volatile solids and lignin removal efficiencies of >80% compared to other systems which showed <50% removal. Sufficient hydraulic retention time, extended aeration system coupled with presence of pure aerobic microbial cells in the stabilisation pond were able to produce effluent that abided the final discharge limit of biochemical oxygen demand 20 mg/L. Stover-Kincannon, Monod Contois and Grau second-order kinetic models were applied to the chemical oxygen demand data obtained to gauge the performance of anaerobic treatment of covered lagoon system with hydraulic mixing. The modified Stover-Kincannon model was found to define the system most appropriately with R2 of 0.9767. This work provided an up-to-date and representative palm oil mill effluent characteristics and contaminants degradation performance of the three commonly used palm oil mill effluent treatment methods in Malaysia. It helps in method selection and equipment sizing for palm oil mill effluent as well as other industrial-scale wastewater treatment and management. • Comparison of different industrial scale of POME treatment was carried out for the first time. • Kinetic analysis on different industrial scale of POME treatment was carried out for the first time. • Modified Stover-Kincannon model is the best-suited kinetic model for the covered lagoon system with hydraulic mixing. [ABSTRACT FROM AUTHOR]

Oil and grease, carbohydrate, protein, and lignin are the main constituents of high strength wastewaters such as dairy wastewater, cheese whey wastewater, distillery wastewater, pulp and paper mill wastewater, and slaughterhouse wastewaters. These constituents have contributed to various operational problems faced by the high-rate anaerobic bioreactor (HRAB). During the hydrolysis stage of anaerobic digestion (AD), these constituents can be hydrolyzed. Since hydrolysis is known to be the rate-limiting step of AD, the overall AD can be enhanced by improving the hydrolysis stage. This can be done by introducing pretreatment that targets the degradation of these constituents. This review mainly focuses on the biological pretreatment on various high-strength wastewaters by using different types of enzymes namely lipase, amylase, protease, and ligninolytic enzymes which are responsible for catalyzing the degradation of oil and grease, carbohydrate, protein, and lignin respectively. This review provides a summary of enzymatic systems involved in enhancing the hydrolysis stage and consequently improve biogas production. The results show that the use of enzymes improves the biogas production in the range of 7 to 76%. Though these improvements are highly dependent on the operating conditions of pretreatment and the types of substrates. Therefore, the critical parameters that would affect the effectiveness of pretreatment are also discussed. This review paper will serve as a useful piece of information to those industries that face difficulties in treating their high-strength wastewaters for the appropriate process, equipment selection, and design of an anaerobic enzymatic system. However, more intensive studies on the optimum operating conditions of pretreatment in a larger-scale and synergistic effects between enzymes are necessary to make the enzymatic pretreatment economically feasible. Unlabelled Image • Lignin, carbohydrate, protein, oil and grease cause operational problems in high-rate anaerobic bioreactor. • Improving hydrolysis stage using enzymes could enhance overall anaerobic digestion. • Usage of enzymes improved biogas production by 7–76%. • pH (7–8), temperature (30–55 °C), and enzyme dosage (1–2%w/w) are optimum conditions for pretreatment. [ABSTRACT FROM AUTHOR]