bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Gravel-Sand Substrate on Sub-Surface Flow Constructed Wetland for Palm Oil Mill Effluent Treatment
Authors: Sa’at S K M , Yusoff M S , Zaman N Q , Ismail H A
Published: May 2021

Constructed wetland as one of technique in phytoremediation, combined and utilized green plants, soil and microorganism in reducing the pollutants in wastewater. Plant selection and types of a substrate are among the factors that contribute to the greater performance of pollutant removal. Gravel and sand are the commonly substrate used in sub-surface constructed wetland because they have acceptability with the hydraulic condition and capable to increase the removal of pollutants in wastewater treatment. In this study, the gravel and sand combination were used to increase pollutant removal. Three (3) sets of experiments were set up as treatment of palm oil mill effluent (POME) which is POME only (PO) as control and, POME with gravel (PG), and POME with gravel-sand (PGS) bed. The POME samples were recirculated through the sub-surface flow constructed wetland for 30 days of treatment. The PGS systems contributes higher performance rather than single gravel or sand with 66% COD, 97% suspended solid, 98% turbidity, 98% ammonia-nitrogen and 99% TN removal and 74% of TP removal. Therefore, the use of gravel-sand substrate is very promising for sub-surface flow constructed wetland treatment systems for POME.
Ethanol Production from Alkaline-treated Rice Straw via Separate Hydrolysis and Fermentation (SHF) using K. marxianus UniMAP 1-1
Authors: Rashid S E R A , Ishak M Z , Rahman K H A , Ismail K S K
Published: May 2021

The decreasing reserves of non-renewable energy especially fossil fuel has led to an urgent need to establish alternative fuels. Ethanol is one of the energies explored, which can be generated by fermentation method. The use of environmentally friendly material such as lignocellulosic biomass to develop a biofuel is significant. Ethanol production at high temperature was preferred as it will significantly reduce the cooling cost involved. Thus, the use of thermotolerant strain in the fermentation process was recommended. In this study, separate hydrolysis and fermentation (SHF) was employed to produce ethanol from 2% sodium hydroxide-treated rice straw using cellulase enzyme, and fermented by a thermotolerant K. marxianus UniMAP 1-1 strain. The fermentation process was done at two different temperatures, 37°C and 50°C, at pH 4.8. The ethanol yield from both 37°C and 50°C was 0.36 g/g and 0.38 g/g, respectively. K. marxianus UniMAP 1-1 showed a good production of ethanol at elevated temperature. This is the first study reporting ethanol production from rice straw using K. marxianus UniMAP 1-1. Thus, this study can improve our understanding of the development of thermotolerant yeast accountable to the SHF process for ethanol production.
Co-anaerobic Digestion of Chicken Manure and Selected Additives for Biogas Production
Authors: Hakimi M , Shamsudin M R , Pendyala R , Aminah S , Gunny A A N
Published: May 2021

Huge amount of chicken manure from poultry producers in Manjung, Perak has caused endemic flies problems across the region. The present study focused on co-anaerobic digestion of chicken manure (CM) with saw dust (SD) and local herbs such as serai wangi (SW), peppermint (PPM) and orange peel waste (OPW) as additives for potential biogas production. The aim of the study was to evaluate the effect of additives towards the biogas production and methane yield of co-anaerobic digestion of chicken manure with saw dust. The C/N ratio of chicken manure and saw dust is 30 and the ratio between feedstock to inoculum is 70:30. The concentration of additives were 10,20 and 30 part per hundred of feedstock (pph f). The operating temperature was 35°C and the experiment was conducted for 50 days. The results show that the co-anaerobic digestion of chicken manure and saw dust with the addition of 10pphf SW has the highest methane yield (59.30%) while the control produced the highest biogas yield (9734 mL). The presence of 10pphf SW for the co-anaerobic digestion of chicken manure and saw dust produced a better quality of biogas.
Continuous Subcritical Water Hydrolysis for Pre-treatment of Palm Oil Mill Effluent (POME)
Authors: Noh SNS , Najwa H , Nawawi N , Yoshida H , Izhar S
Published: May 2021

The pre-treatment of palm oil mill effluent (POME) was carried out using subcritical water (Sub-CW). Sub-CW has the potential as a clean and green method to extract, hydrolyze, gasifier, and carbonize biomass to produce valuable materials. The experiment was conducted continuously for 1 hour at 190, 220, and 260°C between 40 and 140 bars. The hydrolysate obtained was separated into liquid and solid phases. The continuous mode stability was investigated at 3 and 7 mL/min, corresponding to the reactor residence time (RT) of 7 and 3 min, respectively. The flowrate gave a steady trendline with less variation at lower temperatures and slight fluctuation for higher temperatures. The highest solid yield was 0.085 wt.% obtained at 260°C and RT=3 min. The highest sugar yield was 4.44 wt.% at 230°C and RT=3 min. The lowest COD value was 5,504 mg/L achieved at 230°C and RT=3 min. The COD was reduced by 78.9 % of the raw POME. High sugar yield paired with reduced COD reached at 230°C in only 3 min, which is significantly low compared to the ponding system. In conclusion, integrating Sub-CW in a continuous mode as a pre-treatment method offers a promising alternative and sustainable solution for POME treatment.
Extraction of Andrographis paniculata as Material for Developing Soap and Sanitizer
Authors: Bahari R , Kasim K F , Nasaruddin N F Najwa
Published: May 2021

The aim of this work to analyse quantitative study of chemical properties of differentA. paniculataextracts obtained from different extraction methods which are methanol and ethanol extracts by maceration and Soxhlet extraction. This consists of antioxidant activity, total phenolic content (TPC) and total flavonoid content (TFC). This project also aims to study the chemical and physicochemical properties of the developed soap and sanitizer.in order to evaluate the quality of the products. The properties of original extracts were compared with the products in order to investigate the improvement of the antioxidant contents of the products upon addition of the A.paniculataextract to them. The antioxidant activity is evaluated using 2,2-diphenyl-1-picrylhdrazyl test. TPC is determined by using Folin-Ciocalteu calorimetric method where Folin-Ciocalteu reagent is used. TFC is quantified by following aluminium chloride calorimetric method. All the tests are quantified using spectrophotometric. Simple antimicrobial assay by hand printing method on agar plate media was also done to analyze the efficiency of the sanitizers against humans’ pathogens on hands. The results showed theA. paniculatamacerated methanol extract exhibited highest antioxidant activity with 76.027% as well as the highest TPC and TFC with 0.222 mg GAE/ml and 7.500 mg QE/ml. The results also showed both products were able to retain similar antioxidant content, higher TPC and lower TFC to that indicated by the original plant extract used to prepare the products. The result showed the improvement of antioxidant contents of soap and sanitizer upon the addition ofA. paniculataextracts. Therefore,A. paniculataextracts are potent natural ingredients for antioxidant properties purpose and can be used to replace the harmful synthetic ingredients on products formulations.
Investigation of Newly Isolated Methylobacterium sp. as Potential Biofertilizer
Authors: Rahim Ainihayati Abdul , Ibrahim Noor Azlina , Ishak Fatin Nabilah , Mean Lee Jia , Ayub Nur Amimi Muliana , Fazilah Nurul Najah
Published: May 2021

Methylobacterium sp. are pink-pigmented facultative methylotrophs (PPFMs) that can promote plant’s growth due to several physiological characteristics such as the ability to produce phytohormone namely indole acetic acid (IAA) and effective roles in phosphate solubilization and nitrogen fixation process. Members of this genus are ubiquitous in the environment and characterized by its ability to utilize single C compound such as methanol as its energy source. These characteristics made Methylobacterium sp. as potential candidates for biofertilizer. In this study, Methylobacterium sp. were isolated from the leaves of paddy and palm oil tree using Ammonia Mineral Salt (AMS) agar supplemented with methanol. Nine isolates were selected based on the appearance of pink colonies on AMS agar. Several analyses were conducted to evaluate plant growth-promoting activities of the selected isolates. The production of IAA was quantified spectrophotometrically using Salkowski’s reagent, and solubilization of inorganic phosphate was determined using vanadate molybdate assay. The results showed that, all the isolates are capable to produce IAA and solubilize inorganic phosphate. As for nitrogen fixation, the lack/poor growth of the isolates on two nitrogen-free media, namely Burks’s and Jensen media manifested the absence or weak nitrogen fixing activity. Findings from these qualitative and quantitative analyses are vital and it will serve as preliminary data for the future exploration of Methylobacterium sp. as biofertilizer.
Small Scale Bubbling Fluidized Bed Gasifier for Syngas Extraction from Napier grass
Authors: Atienza A H , Aceituna A , Samar X E
Published: May 2021

For some farmers, Napier grass is non-beneficial since it may compete for growth area and nutrients for common agricultural crops. However, this grass has the potential to become biomass energy source. It is known that Napier grass is a candidate source of syngas or synthetic gas which can be utilized in different applications. To extract synthetic gas, the Napier grass must undergo gasification process. This study focuses on the design and testing of a small-scale bubbling fluidized bed gasifier for Napier grass. The reactor chamber is made up of low carbon steel while the inert bed material used is silica. The materials for the gasifier were chosen by using the quantitative method of material selection. The temperatures at the inlet, sections of the reactor and exhaust of the reactor were monitored. The maximum furnace temperature of the gasifier was 473°C and observed after 170 minutes due to increased furnace and reactor heating surface area. The syngas extracted from the gasifier was tested and analyzed that there is 21.23 ppm of Carbon Monoxide (CO) and low Volatile Organic Compound (VOC) content. The composition of syngas conformed with the standards and can be used for cooking applications
Preliminary analysis of Endophytic Plant Growth Promoting (PGP) Methylobacterium sp. Isolated from Palm Oil (Elaeis guineensis) Leaves
Authors: Ishak Fatin Nabilah , Rahim Ainihayati Abdul , Mean Lee Jia , Ayub Nur Amimi Muliana , Fazilah Nurul Najah
Published: May 2021

The genus Methylobacterium is known for its pink-pigmented facultative methylotrophs (PPFMs). They are able to utilize methanol emitted from plants and in return produce plant growth promoting substances. The genus Methylobacterium can be found in diverse habitats and they are known particularly for their close association with plants. The aims of this study are to isolate and characterize endophythic Methylobacterium sp. from palm oil leaves. Isolation of Methylobacterium sp was conducted using Ammonia Mineral Salts (AMS) agar supplemented with methanol. Three isolates were selected namely ENPM1, ENPM2 and ENPM3. Production of IAA by the selected isolates was evaluated under different concentration of L-tryptophan as an inducer. It was observed that the amount of(IAA) produced increased when higher concentration of tryptophan was used and ENPM1 recorded the highest amount of IAA production (1.930 μg/mL) at the 1000 μg/mL concentration of L-tryptophan. The ability to solubilized inorganic phosphate was investigated using Solubilisation Index (SI) assay on phosphate solubilisation media (PSM). The largest clear zone formation on PSM agar was shown by ENPM3 with the SI 1.5. As for nitrogen fixation, the growth of the selected isolates on two nitrogen free media namely Burk’s and Jensen media indicates potential nitrogen fixing activity.
Methanolysis of Ceiba Petandra (Kapok) seed for high yield fatty acid methyl ester (FAME): A parametric study
Authors: Herman Indah Thuraya , Mukhrofun Faridah , Isa Khairuddin Md , Ibrahim Naimah , Abd Aziz Mohd Aizudin
Published: May 2021

The feedstock that has high potential for biodiesel production was investigated. The ceiba petandra (CP) seed was used in this study as the feedstock. The methanolysis of the CP seed to produce high yield of Fatty Acid Methyl Ester (FAME) was studied. Hydrothermal liquefaction (HTL) was used to produce the bio-crude from the CP with high ester yield. The gas chromatography-mass spectrometry was used to analyze the chemical content in the bio-crude. The highest oil yield was 44.68% which was obtained at 60 minutes reaction time, 300°C temperature and 4:1 methanol/oil mass ratio. The optimum parameters for the highest ester content (67.33%) was obtained at 60 minutes reaction time, 300°C temperature and 3:1 methanol/oil mass ratio. It is observed that CP seed has potential for the production of biodiesel.
Rapid and non-destructive leaf chlorophyll estimation of Fig (Ficus carica L.) cv. Iraqi grown on different root zone spatial limitation and controlled porosity level under greenhouse condition
Authors: Isa M M , Kasim K F , Muttalib M F A , Jaafar M N
Published: May 2021

The estimation of chlorophyll content in leaves by the chlorophyll meter (SPAD 502) is more favourable than by the extraction method for studies on photosynthesis or senescence where the total chlorophyll is estimated on the same leaf over time. However, till date there is lack of information available on leaf chlorophyll content of Fig (Ficus carica L.) cv. Iraqi grown in containers under different root zone spatial limitation and controlled porosity level. Hence, this study aim to determine the effect of both factors on leaf chlorophyll content of the crop. The experiment was design in randomized complete block design (RCBD) with four replications. The Soil-Plant Analyses Development (SPAD) chlorophyll meter (Minolta Camera Co., Ltd., Japan), has been used for instantly measuring the amount of chlorophyll present in plant leaves. Based on the results, the application of Mix 3 (50% sand: 50% clay) with high root zone spatial gave the highest chlorophyll content compared to other treatment. The application of the right root zone and porosity level may gave positive effect on leaf chlorophyll content of F. carica cv. Iraqi grown under greenhouse condition.
Investigation of Vortex-Induced Vibration with Different Width of Two Bluff Bodies in Tandem Arrangement for Energy Harvesting System
Authors: Aziz NA , Kazim MNFM , Amin NAM , Majid MSA , Rojan A , Nasir NFM
Published: May 2021

Due to imperative of enhancement on Vortex-induced vibration (VIV) energy harvesting as renewable energy sources, dual bluff bodies which are triangle and cylinder in tandem arrangement with different width from each other are studied in terms of total deformation, directional deformation and voltage generated in order to determine the better bluff bodies for the piezoelectric film. This is due to the unsymmetrical wakes pattern, low frequency vortices, and low energy output produced by the system. The length and height of the bluff bodies were fixed to 0.1m and airflow used for simulations was 1.46m/s. The spacing ratio was calculated from 1 to 6 to examine various width between two bluff bodies that will affect the formation of the vortex at the downstream area. From the results, it can be concluded that triangle bluff bodies in tandem arrangement 0.6m from each other have resulted in the highest total deformation and effective voltage generated of 0.47mm, and 3.05mV, respectively. These data indicated the highest ability of energy harnessing. Furthermore, this model results in a consistent flagging direction of the piezoelectric that implying a good energy harvesting system.
Prediction of Ionic Liquids Performance for Hydrogen Sulfide Absorption from Natural Gas using COSMO-RS
Authors: Mohd Khasiran Z , Johari K , Man Z , Bustam M A
Published: May 2021

The capability of ionic liquids (ILs) in various applications makes them attracted by many researchers. They have potential to be developed as “green” solvents for gas separation, especially hydrogen sulfide (H 2S) gas. In this work, it is attempted to predict the solubility of H 2S in ILs by COSMO-RS method. Since H 2S is a toxic pollutant, it is difficult to handle in the laboratory, therefore an appropriate model will be necessary in prior work. The COSMO-RS method is implemented to predict the Henry’s law constants and activity coefficient of H 2S in 140 ILs with various combinations of cations and anions. It is found by the screening that more H 2S can be absorbed in ILs with chloride ([Cl]-) and acetate ([Ac]-) anion. The solubility of H 2S in ILs with different alkyl chain at the cations not much affected and with different type of cations are slightly influence H 2S capture capacities. Even though the cations do not affect much in solubility of H 2S, the effectiveness of cation still need to be considered in different way. The prediction results only show their physical absorption ability, but the absorption of H 2S need to be consider chemically to get high capacity of absorption of H 2S.
Characteristics and carbon dioxide adsorption performance of candle soot-activated by potassium hydroxide
Authors: Fathihah M A , Khairunnisa M P
Published: May 2021

Incomplete combustion by fossil fuel has contributed to the increase in carbon dioxide (CO 2) emission as well as carbon soot production. Several methods have been done via carbon capture and storage (CCS) strategy to mitigate CO 2 emission such as via adsorption. However, a method to utilize the carbon soot production was still in question. Less discussion on utilizing soot as gas adsorbent up to this date. Therefore, this paper aimed to investigate the CO 2 adsorption performance from fresh candle soot (FS) and soot activated by potassium hydroxide (KOH) with mass ratio 2/1 KOH to soot (KOH-S1). The activation process was done by using muffle furnace at 700 °C for 1 h under vacuum condition. FTIR spectrum of the KOH-S1 appeared at 3500, 1639, 1048 and 1740 cm -1 due to KOH treatment before activation. The mean diameter for KOH-S1 particles was larger (22.328 μm) than FS (4.413 μm) due to agglomeration. The adsorption capacity obtained for KOH-S1 and FS were 24.4092 and 10.3052 mg/g respectively. It has been demonstrated that KOH-S1 has excellent potential to be used for CO2 adsorption and more studies need to conducted for its development.
Assessment of copper-iron catalyst supported on activated carbon for low-temperature nitric oxide reduction by hydrogen
Authors: Ibrahim Y , Hardyman B Mohamad , James McG
Published: May 2021

It is pertinent to assess the performance of a sustainable system that can treat nitrogen oxides (NO x) emissions from combusting biomass waste. Low-temperature selective catalytic reduction is attractive due to the longer catalyst lifetime and the possibility to use carbon-based catalysts. Hence, this study explores this system with the utilization of: (i) a cost-effective catalyst support, i.e. activated carbon derived from abundant biomass waste; (ii) a renewable reductant, i.e. hydrogen; and (iii) Earth-abundant metal catalysts, i.e. copper and iron. The catalyst was prepared by impregnating metal oxides (Cu and Fe) over palm kernel shell activated carbon (PKS). The catalyst was characterised by hydrogen-temperature programmed reduction (H 2-TPR) and nitric oxide-temperature programmed desorption (NO-TPD). H 2-TPR revealed an increase in the reducibility, attributed to the synergistic effects between Cu and Fe. However, these catalyst sites favour nitrous oxide (N 2O) formation as shown via NO-TPD. Meanwhile, the catalyst activity has also been investigated in a fixed-bed reactor. It showed that the 100% conversion can be achieved at 200°C, but the selectivity towards nitrogen formation is as low as 40%. Therefore, investigating the optimum design of PKSCuFe catalyst is justifiable to improve the performance of low-temperature selective catalytic reduction.
Lake Water Effect on the Performance of Concrete
Authors: Shamilah A A , Norfathin A A
Published: May 2021

This study was related to the application of lake water in the production of concrete samples as partial replacement to freshwater. The effect of the applications in terms of concrete properties were determined and compared with normal concrete samples that were cast with fresh water. The lake water was collected at Tasik Timah Tasoh, Perlis. In this study, the percentage of water replacement were 50%, 80% and 100%. A standard mix ratio of concrete was used. The main objective of this study was to investigate the compressive strength of concrete cube casting using lake water replacement. The test conducted in this laboratory works were compression, density, water absorption and Ultrasonic Pulse Velocity. Among the 3 different percentage of lake water replacement used in this study, it found that 100% amount of lake water indicates higher compressive strength as compared with the control sample. This indicates the good agreement between lake water and cement to be combined for concrete casting.
Oil-palm empty fruit bunch fiber reinforcement in concrete-foam application for floating platform
Authors: Somkeattikul Kreetha , Areeprasert Chinnathan , Kiatiwat Thanya
Published: May 2021

This paper focuses on fiber reinforcement of concrete-foam material (CFM) for floating platform. Oil-palm empty fruit bunch fiber (EFB-F) was selected to mix with CFM. Initially, three composition ratios of CFM were produced and tested to optimize the curing time. Then, the EFB-F was mixed with the optimized CFM. Several ratios of EFB-F and optimized CFM were used to study the effect of fiber reinforcement. Mechanical properties namely, compressive strength and tensile strength from flexural test were investigated. Several designs and compositions of the floating platform were studied to optimize strength and floatability (as composite material density). The research and testing results, it can be concluded that the cement-foam-EFB-F composite material has a higher density, resulting in higher compressive strength and tensile strength. Therefore, Oil-palm empty fruit bunch fiber, a waste material from manufacturing processes, can be utilized as an ingredient to improve the mechanical properties of foam cement for floating platforms.
Kinetics, isotherm and thermodynamic modeling of liquid phase saponin sorption in soils
Authors: Wahab W R A , Yusup S
Published: May 2021

The sorption behavior of saponin onto clay, paddy, silty loam and sandy soil was thoroughly evaluated in this study. The adsorption kinetic, isotherm and thermodynamic were conducted in batch analysis. Pseudo-first order, pseudo-second order and Elovich kinetic models were applied to evaluate the kinetics of the adsorption. Based on the models, the adsorption of saponin onto soils were mostly governed by physisorption while chemisorption also plays a role in the adsorption process in clay and paddy soil. Mechanism of adsorption was determined by adopting the intraparticle diffusion and Boyd models. The two models concluded that intraparticle diffusion is not the rate-limiting step in saponin uptake in all four soil types. Equilibrium isotherm was evaluated by using Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. The data obeys both Langmuir and Freundlich model, however, Langmuir model tends to overestimate the qe value of the given soil. Clay soil showed highest maximum adsorption, followed by paddy, silty loam and sandy soil. Effects of temperature variation is minimal while variation in pH value was significant where optimum adsorption was achieved at near-neutral pH range. The thermodynamic study showed that the adsorption process was exothermic and spontaneous.
The potential of water hyacinth in the phytoremediation of industrial wastewater
Authors: Chun L K , Saifuddin M N A A , Fauzi A H Mohammad
Published: May 2021

In this study, the potential of water hyacinth in the phytoremediation of simulated wastewater containing copper (Cu) and lead (Pb) was studied. Locally available water hyacinth was collected from an uncontrolled environment. The prepared samples were segregated into three different parts (i.e., leaf, stem, and root), ground into powder, and used as the adsorbent for heavy metal removal. Acid digestion method was utilized for the preparation of the samples prior to atomic absorption spectrometry (AAS), and AAS was performed to determine the heavy metal concentration for each plant part. Based on the baseline study for identifying the heavy metal content in raw water hyacinth, Cu and Pb mostly accumulated in the root. The pH of simulated wastewater dropped upon the addition of Cu, and the pH gradually increased to 7 after day 7 onward. The overall removal efficiency of Cu decreased from 98.7% to 91.6% as the Cu concentration increased from 1 mg/L to 5 mg/L. Meanwhile, the overall removal efficiency of Pb decreased from 73.6% to 31.3% as the Pb concentration increased from 250 mg/L to 750 mg/L. Thus, water hyacinth is useful for treating wastewater containing heavy metals, particularly Cu and Pb.
Mangosteen Peel-Derived Hydrochar Prepared via Hydrothermal Carbonization for Methylene Blue Removal
Authors: Hamid N A , You J J
Published: May 2021

Hydrothermal carbonization (HTC) arises as an improved carbonization step developed to enhance the carbon porosity and reduce the production cost by thermally treating feedstock under milder operating conditions. This work aimed to generate hydrochar from mangosteen peel (MPHTC) via hydrothermal carbonization for the removal of methylene blue from aqueous solution. In the study, hydrochar was synthesized at an optimized carbonization temperature (200 °C) with a production yield of 82.75% and a methylene blue removal of 75.93%. The adsorption capacity of adsorbent enhanced with the increasing initial dye concentration due to high driving force for efficient mass transfer. The hydrochar was capable of attaining its maximum adsorption capacity at 131.58 mg/g. The derived hydrochar performed a higher uptake of dye molecules under basic conditions rather than acidic conditions owing to the presence of OH group for the attachment of cationic dye. It was determined that Freundlich isotherm and pseudo second order kinetic models best fitted the experimental data. External film diffusion was found to be the rate-controlling step for the batch adsorption process. The results revealed that MPHTC is a promising adsorbent for treatment of cationic dye for effluent wastewater.
Electricity Generation by Locally Isolated Electroactive Bacteria in Microbial Fuel Cell
Authors: Jamlus N I I M , Masri M N , Wee S K , Shoparwe N F
Published: May 2021

Electroactive bacteria can transfer electrons to electrodes to generate electricity in the microbial fuel cell (MFC). Electroactive bacteria can generate energy for growth via the oxidation of organic compounds and transfer electrons to the electrodes that serve as the terminal electron acceptor. In this study, electricity generation in a double chamber evaluated MFC by four newly isolated electroactive bacteria strains (ESPK 22, ESPK 26, KP20, and KP22). ESPK22 and ESPK26 were previously identified as gram-positive Bacillus genera, while KP20 and KP22 belong to gram-negative Klebsiella genera. Among all the strains tested, the gramnegative KP20 strain shows the highest electricity generation value is 222.08 mV and the lowest electricity generation was ESPK26 of 44.82 mV.
Methomyl removal from synthetic water using natural and modified bentonite clays
Authors: León H , Almeida-Naranjo C , Aldás MB , Guerrero VH
Published: May 2021

The removal of methomyl from synthetic aqueous solutions by using Ecuadorian bentonite clays was studied. A natural clay was purified (P-C) and modified by three methods: thermal activation at 200°C for 2 h, acid activation with a 3N sulfuric acid solution for 1 h, and saline activation with hexadecyltrimethyl ammonium bromide (HDTMA) for 12 h. Clays were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and the BET method. The removal was performed with the natural and modified bentonites considering three particle size ranges and three operating temperatures (20, 30 and 40°C). For this purpose, 0.5 g of clay were added to 50 mL of a 100 µg L−1 synthetic methomyl wastewater. Pesticide removal was quantified using ultraperformance liquid chromatography - tandem mass spectrometry. It was found that the adsorption process can be relatively efficient, particularly with thermally activated clays being used at 40°C. In this case, removal efficiencies between 66 and 76% were achieved. The highest efficiency was observed for a relatively large particle size (106-150 µm). The adsorption curves obtained were fitted to the Langmuir model. The analysis of variance for the removal of methomyl showed a significant effect for the temperature x clay x particle size interaction with a confidence level of 95% (p = 0.004).
Sanitation inspection of household fecal containment in Bekasi, Indonesia
Authors: Septarini A , Islami B B , Putri G L , Pratama M A , Foster T , Willetts J , Priadi C R
Published: May 2021

On-site sanitation (OSS) is widely known as the preferred system in Indonesia, providing low-cost wastewater treatment. The majority of households use pour-flush latrines coupled with containment in the form of cubluks or septic tanks, but compliance with relevant technical and maintenance standards is low. Poorly designed and unmanaged containment may not treat fecal waste effectively, potentially contaminating the groundwater and the soil and threatening human health. This study aimed to determine the condition and effluent quality of household fecal containment in Bekasi City. A social and technical survey was conducted through questionnaires and observations of 260 households in three poor urban villages of Jatiluhur, Sumur Batu, and Jatirangga, to obtain data on containment design, construction, operation, and maintenance. Effluent samples were collected from eight households, and laboratory tests were conducted to determine the chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), ammonia, and E. coli levels. The data was analyzed with descriptive statistics, and the sanitation facilities in the three villages were categorized as safely managed (0.8%); basic (66%); limited (2.3%); unimproved (29%); and open defecation (1.5%) based on JMP sanitation ladder. On average, the effluent samples exceeded relevant quality standards, except regarding BOD (10.9 ± 4.14 mg/L) and pH (7 ± 0.3). The results of this study can be used as a baseline to improve the conditions of sanitation facilities in poor areas.
Development of a complex system models in mixed municipal waste bales
Authors: Dmitrovic Lovorka Gotal
Published: May 2021

The development of the organic matter decomposition model in mixed municipal waste is presented in the paper. The decomposition takes place in two main processes: aerobic and anaerobic. The whole system, according to system theory, belongs to complex ecosystems. Model development begins with conceptualisation. Because the process belongs to hybrid systems (continuous and discrete states are changing) for conceptualization, the model for discrete simulation (the Activity Cycle Diagram (ACD)), but also for systems dynamics (Flow Chart) was used. To evaluate the simulation model, the Rank Sum Test (or Mann-Whitney U-test) was used. The research conducted for the purposes of this paper is reflected in an interdisciplinary field covering information science and ecology and environmental protection (eco-informatics), which enables the systematic study and proposing of measures for environmental protection, by transferring environmental testing to the simulation model. The developed model is adaptive and portable, in terms of the application of such systems at other locations, that is, with different values of input pollution concentrations. Methods of modelling and conceptualizing such situations contribute significantly to environmental protection and human health.
Socially engaged Buddhism: cattle-breeding initiative of the Buryat Buddhist sangha and its ecological significance in the Baikal region, Russia
Authors: Dondukov B , Dorzhigushaeva O , Dondukova G
Published: May 2021

The article focuses on the environmental consequences of abandoning rural life, increasing urbanization and the problem of deforestation in the Baikal region, Russia. Specifically, it analyzes a recently proposed “Social Flock” project of the Buryat Buddhist community for the revival of nomadic cattle breeding in the districts of Buryatia, and its potential impact on the environment. We argue that taking into consideration the global value of the Lake Baikal, the “Social Flock” project can not only satisfy the practical needs of people and reduce the social aspects of environmental problems in Buryatia, but also potentially contribute to dealing with environmental problems of global importance.
Techno-economic comparison between photovoltaic systems with solar trackers and fixed structure in “El Valle de Sula”, Honduras
Authors: Andino García H , Reyes Duke A , Villatoro Flores H
Published: May 2021

Solar energy has the greatest energy potential among all types of renewable energies. In 2018, the annual demand for electricity worldwide was 22,964 TWh. Daily, earth receives about 174 PW in the form of solar irradiance. This means that, if all this radiation could be harnessed, in approximately 8 minutes the electricity needed to meet the global annual electricity demand could be generated. Therefore, the need arises to implement photovoltaic systems that take better advantage of the solar resource, but in turn provide greater economic profitability. This article aims to evaluate the technical and economic feasibility of photovoltaic systems with solar trackers and compare them with fixed structure systems in “El Valle de Sula”, Honduras, Central America. The research was able to determine the levelized cost of electricity (LCOE) of each type of photovoltaic system from the generation of electricity in municipalities comprising the study area and the costs associated with initial investment, and operation and maintenance of each photovoltaic system. This research was carried out by implementing a methodology with a quantitative approach, using data collection to test hypotheses, based on numerical measurement and statistical analysis. Considering the value of the land, the photovoltaic system with a horizontal axis tracker has the lowest LCOE in 14 of the 18 municipalities of “El Valle de Sula”. Without taking into account the value of the land, the system with the lowest LCOE in all municipalities of this region is the system with a horizontal axis tracker, then the system with a dual-axis tracker and finally the system with fixed structure.
Design of a vertical axis wind turbine for pedagogical purpose using solidworks CAD
Authors: Jiménez H F , Carrasco A M , Ordoñez Avila J L
Published: May 2021

This project was based on the design and simulation of a vertical axis wind turbine for pedagogical purposes. It must operate at low speeds without the implementation of expensive technology. In order to achieve this, the V methodology was used because it provides a practical tool for the development of projects, allowing the researcher to carry out the integration of the three subsystems of mechatronics engineering: mechanics, electronics, and computer. The final design of the wind turbine has a rotation diameter of 1.2 m and a 2.4 m height and an average flow of 1.5 m/s.
Technical and economic review of the reconversion of refrigerants in an air conditioner: HFCF to HC in Honduras
Authors: Leiva Carvajal D , Reyes Duke A , Carrasco Bardales A , Amador Iscoa P
Published: May 2021

This paper presents the result of a non-experimental investigation on the reconversion of an air conditioner replacing its refrigerant R22 for R290 to achieve a more environmentally sustainable system. First a cooling load analysis was conducted to determine the thermal power that must be extracted from the working area. An ideal thermodynamic cycle was designed based on the usual performance of this system; Engineering Equation Solver was used to analyze the system performance. To study R290 implementation in the original system two cases were proposed: maintaining the same cooling capacity and using 50% of the original mass for the new refrigerant. In the first case capacity flow mass rate, mass charge, compression ratio and refrigerant effect was better for R290, but COP and EER was higher in R22 systems determining a better performance overall. In the second analysis a better performance for the system was obtained. Also, an economic overview of the reconversion is offered, resulting in a cost benefit higher than 1 which indicates a project where the inversion made turns in benefits in long term. To end the emissions of each refrigerant was calculated and R290, as expected, showed considerably lower emissions compared to R22.
Periodic solutions of partial functional differential equations
Authors: Su Qiuyi , Ruan Shigui
Published: May 2021

In this paper we study the existence of periodic solutions to the partial functional differential equation
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="StartLayout Enlarged left-brace 1st Row StartFraction d y left-parenthesis t right-parenthesis Over d t EndFraction equals upper B y left-parenthesis t right-parenthesis plus ModifyingAbove upper L With caret left-parenthesis y Subscript t Baseline right-parenthesis plus f left-parenthesis t comma y Subscript t Baseline right-parenthesis comma for-all t greater-than-or-equal-to 0 comma 2nd Row y 0 equals phi element-of upper C Subscript upper B Baseline period EndLayout">

{

d
y
(
t
)

d
t

=
B
y
(
t
)
+

L
^

(

y

t

)
+
f
(
t
,

y

t

)
,

∀
t
≥
0
,

y

0

=
φ
∈

C

B

.

\begin{equation*} \left \{ \begin {array}{l} \frac {dy(t)}{dt}=By(t)+\hat {L}(y_{t})+f(t,y_{t}), \;\forall t\geq 0,\\ y_{0}=\varphi \in C_{B}. \end{array} \right . \end{equation*}

where

B
:
Y
→
Y

B: Y \rightarrow Y

is a Hille-Yosida operator on a Banach space

Y
Y

. For
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" alttext="upper C Subscript upper B Baseline colon-equal StartSet phi element-of upper C left-parenthesis left-bracket negative r comma 0 right-bracket semicolon upper Y right-parenthesis colon phi left-parenthesis 0 right-parenthesis element-of ModifyingAbove upper D left-parenthesis upper B right-parenthesis With bar EndSet">

C

B

≔
{
φ
∈
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(
[
−
r
,
0
]
;
Y
)
:
φ
(
0
)
∈

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(
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)

¯

}

C_{B}≔\{\varphi \in C([-r,0];Y): \varphi (0)\in \overline {D(B)}\}

,

y

t

∈

C

B

y_{t}\in C_{B}

is defined by

y

t

(
θ
)
=
y
(
t
+
θ
)

y_{t}(\theta )=y(t+\theta )

,

θ
∈
[
−
r
,
0
]

\theta \in [-r,0]

,

L
^

:

C

B

→
Y

\hat {L}: C_{B}\rightarrow Y

is a bounded linear operator, and

f
:

R

×

C

B

→
Y

f:\mathbb {R}\times C_{B}\rightarrow Y

is a continuous map and is

T
T

-periodic in the time variable

t
t

. Sufficient conditions on

B
B

,

L
^

\hat {L}

and

f
(
t
,

y

t

)

f(t,y_{t})

are given to ensure the existence of

T
T

-periodic solutions. The results then are applied to establish the existence of periodic solutions in a reaction-diffusion equation with time delay and the diffusive Nicholson’s blowflies equation.
A Novel Peptide Ameliorates TNFα- and LPS-Induced Endothelia Dysfunction in Preeclampsia
Authors: Ji Xiaohong , Li Chanjuan , Lv Yan , Miao Zhijing , Wu Lan , Long Wei , Wang Xing , Ding Hongjuan
Published: May 2021

Background

To investigate the protective effects of the novel peptide antiendothelial dysfunction peptide in preeclampsia (AEDPPE) on tumor necrosis factor α (TNFα)- and lipopolysaccharide (LPS)-induced injury in the vascular endothelium in preeclampsia.

Methods

The effects of AEDPPE on TNFα-induced vascular endothelial injury were assessed by enzyme-linked immunosorbent assay, quantitative real-time PCR, mitochondrial membrane potential assay, Cell Counting Kit-8 assay, THP-1 monocyte–human umbilical vein endothelial cell (HUVEC) adhesion assay, endothelial tube-forming assay, transcriptomic analysis, preeclamptic symptom analysis, and histological analysis in preeclampsia-like rat models induced by LPS.

Results

AEDPPE alleviated the upregulation of antiangiogenic factors including soluble fms-like tyrosine kinase-1, endothelin-1, and tissue plasminogen activator and attenuated the reduction in mitochondrial potential induced by TNFα in HUVECs. In addition, AEDPPE treatment counteracted the decrease in tube formation and decreased the numbers of THP-1 monocytes attached to HUVECs caused by TNFα. Mechanistically, cytokine–cytokine receptor interactions enriched many genes and the TNF signaling pathway may be involved in this phenomenon. Moreover, cotreatment with LPS and AEDPPE significantly reversed the preeclampsia-like phenotype including hypertension and proteinuria and improved the functions of the kidney and placenta.

Conclusions

AEDPPE effectively ameliorated the vascular endothelial injury induced by TNFα and LPS in preeclampsia. We suggest that AEDPPE may be a novel therapeutic candidate for preeclampsia treatment. These findings demonstrate that AEDPPE may play an effective role in ameliorating vascular endothelial dysfunction and be a potential therapeutic agent for preeclampsia.
SimText: a text mining framework for interactive analysis and visualization of similarities among biomedical entities
Authors: Macnee Marie , Pérez-Palma Eduardo , Schumacher-Bass Sarah , Dalton Jarrod , Leu Costin , Blankenberg Daniel , Lal Dennis
Published: May 2021

Literature exploration in PubMed on a large number of biomedical entities (e.g. genes, diseases or experiments) can be time-consuming and challenging, especially when assessing associations between entities. Here, we describe SimText, a user-friendly toolset that provides customizable and systematic workflows for the analysis of similarities among a set of entities based on text. SimText can be used for (i) text collection from PubMed and extraction of words with different text mining approaches, and (ii) interactive analysis and visualization of data using unsupervised learning techniques in an interactive app.

Availability and implementation

We developed SimText as an open-source R software and integrated it into Galaxy (https://usegalaxy.eu), an online data analysis platform with supporting self-learning training material available at https://training.galaxyproject.org. A command-line version of the toolset is available for download from GitHub (https://github.com/dlal-group/simtext) or as Docker image (https://hub.docker.com/r/dlalgroup/simtext/tags.).

Supplementary information

Supplementary data are available at Bioinformatics online.
LevioSAM: fast lift-over of variant-aware reference alignments
Authors: Mun Taher , Chen Nae-Chyun , Langmead Ben
Published: May 2021

Motivation

As more population genetics datasets and population-specific references become available, the task of translating (‘lifting’) read alignments from one reference coordinate system to another is becoming more common. Existing tools generally require a chain file, whereas VCF files are the more common way to represent variation. Existing tools also do not make effective use of threads, creating a post-alignment bottleneck.

Results

LevioSAM is a tool for lifting SAM/BAM alignments from one reference to another using a VCF file containing population variants. LevioSAM uses succinct data structures and scales efficiently to many threads. When run downstream of a read aligner, levioSAM is more than 7 times faster than an aligner when both are run with 16 threads.

Availability and implementation

Software Package: https://github.com/alshai/levioSAM, Experiments: https://github.com/langmead-lab/levioSAM-experiments

Supplementary information

Supplementary data are available at Bioinformatics online.
White Matter Structural and Network Topological Changes Underlying the Behavioral Phenotype of MECP2 Mutant Monkeys
Authors: Wang Jiaojian , Wang Zhengbo , Zhang Hongjiang , Feng Shufei , Lu Yi , Wang Shuang , Wang Hong , Sun Yi Eve , Chen Yongchang
Published: May 2021

To explore the brain structural basis underlying the behavioral abnormalities associated with Rett syndrome (RTT), we carried out detailed longitudinal noninvasive magnetic resonance imaging analyses of RTT monkey models created by gene-editing, from weaning, through adolescence, till sexual maturation. Here, we report abnormal developmental dynamics of brain white matter (WM) microstructures and network topological organizations via diffusion tensor imaging. Specifically, disrupted WM microstructural integrity was observed at 9 months, but recovered thereafter, whereas WM network topological properties showed persistent abnormal dynamics from 9 to 37 months. Changes in the WM microstructure and WM network topology were correlated well with RTT-associated behavioral abnormalities including sleep latency, environmental exploration, and conflict encounters. Deleterious and protracted early WM myelination process likely lead to abnormal synaptic pruning, resulting in poor functional segregations. Together, this study provides initial evidence for changes in WM microstructure and network topological organization, which may underlie the neuro-patho-etilogy of RTT.
A Fully Validated UHPLC–MS/MS Method for the Estimation of Pimavanserin in Human (K2EDTA) Plasma and its Application to a Clinical Pharmacokinetic Study
Authors: Aalapati Kiran Kumar , Singh Amit , Patnaik Ranjana S
Published: May 2021

A simple, fast and extremely sensitive for estimating Pimavanserin in human (K2EDTA) plasma using ultra high-performance liquid chromatography combined with tandem mass spectrometry (UHPLC–MS/MS) was newly developed and validated. Sample extraction was accomplished using a partition liquid extraction (LLE—liquid–liquid extraction) procedure utilizing extraction solvent, methyl tertiary butyl ether. Separation of the components, chromatography, was done using a C18 chromatographic analytical column employing acetonitrile:methanol: 0.1% formic acid solution (40:40:20 volume by volume) pumped with 0.800 mL/min as the flow rate. For Pimavanserin, the established methodology was linear throughout the calibration curve range from 0.25ng/mL till 50.0 ng/mL. Results of intraday and interday accuracy and precision of Pimavanserin met recent regulatory requirements. This methodology was effectively used to estimate Pimavanserin in vivo human (K2EDTA) plasma concentration for a clinical pharmacokinetic study.