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1.
IOP Conference Series. Earth and Environmental Science ; 1114(1):012082, 2022.
Article in English | ProQuest Central | ID: covidwho-2160871

ABSTRACT

This study aim to improve the quality of Phyllanthus sp production by increasing the content of secondary metabolites as a bioactive compound. Phyllanthus sp contains various secondary metabolites that enhance immunity and treat diabetes, hypertension, antioxidants, anti-cancer, kidney disorders, and other illnesses. Since the Covid-19 pandemic, Phyllanthus sp widely used as a raw material for making herbal medicines. The trade value of Indonesian herbal medicines is estimated to increase in 2022, and the price will reach around the US $ 910 million, so it has very bright business prospects. These relatively limited phytopharmaceutical products constrain the supply of high-quality raw materials under the requirements of the herb medicine industry. Therefore, conducting a depth assessment related to efforts to improve the quality of Phyllanthus sp production by increasing the content of secondary metabolites is necessary. The efforts to enhance the quality of Phyllanthus sp as a source of herbal medicine raw materials can be made through plant breeding such as genetic mutations and in combination with the environmental arrangements of soil water content and solar radiation intensity. The efforts to increase the quality of herbal medicine raw materials are critical to support the development of the herbal medicine industry.

2.
Ecography ; 2022(12), 2022.
Article in English | ProQuest Central | ID: covidwho-2136814

ABSTRACT

The spatiotemporal variability of vegetation fires is essential for understanding changes in the climate and ecosystem in mountainous regions. MODIS Collection 6 active fire products indicate that the area burned by vegetation fires declined globally from over 4.27 million km2 to less than 3.52 million km2 annually during 2001–2021. In contrast, global high mountains higher than 3000 m have experienced an overall increase in their burned area and suffered record‐breaking wildfires from August to December 2020. Although high mountains accounted for less than 0.03% of the global burned area during 2001–2021, this proportion had more than tripled by 2020. This unprecedented wildfire record in 2020 could be mainly caused by favorable fire weather conditions such as low relative humidity, low soil water and high temperature.

3.
IOP Conference Series. Earth and Environmental Science ; 1098(1):012016, 2022.
Article in English | ProQuest Central | ID: covidwho-2118176

ABSTRACT

The abundance of plastic waste in Indonesia has increased due to the contribution of disposable masks waste during the COVID-19 pandemic. The improper waste management causes the habit of dumping waste in the soil system to still frequently occur. The secondary microplastics from disposable mask waste has the potential to damage soil quality and soil capillary water. Therefore, this study was conducted with the aim of understanding the effects of disposable mask waste in peat soil. The research was conducted by setting up 3 reactors containing peat soil with disposable mask waste buried in it and some plants being grown on it. For 45 days, observations and samples were taken, both filtrate water and soil for analysis. The analysis results showed significant changes in soil properties with changes in the concentration of inorganic matter, organic matter, porosity, bulk density, and water content. Further research needs to be done to see the effects of disposable mask waste in the soil system in real conditions where several confounding variables cannot be controlled.

4.
Sustainability ; 14(17):10862, 2022.
Article in English | ProQuest Central | ID: covidwho-2024206

ABSTRACT

The waste generated by small-scale ultra-fresh juice producers, such as bistros and restaurants, has been little studied so far, mainly because it is unevenly distributed and dissipated in the economic ecosystem and would require high costs associated with transportation and subsequent recovery of bio composites. The present article seeks to offer solutions by providing sustainable methods to reduce their waste losses to a minimum and transform them into valuable products, with affordable equipment and techniques. The study focuses on the preliminary phase of quantitative analysis of fruit and vegetable by-products generated on a small scale, the results showing a mean 55% productivity in fresh juices. Due to the high amount of remnant water content in waste, a new process of mechanically pressing the resulting squeezed pulp was introduced, generating an additional yield in juice, ranging from 3.98 to 51.4%. Due to the rising trend in healthier lifestyle, the by-products were frozen or airdried for conservation in each of the processing stages, and the total phenolic compounds and antioxidant activity were analyzed in order to assess the traceability of these bioactive compounds to help maximize their transfer into future final products. The polyphenols transferred into by-products varied between 7 and 23% in pulps and between 6 and 20% in flours. The highest DPPH potential was found in flours, up to three-fold in comparison with the raw material, but the high dry substance content must be accounted for. The results highlight the potential of reusing the processing waste as a reliable source of bioactive compounds.

5.
Atmosphere ; 13(8):1272, 2022.
Article in English | ProQuest Central | ID: covidwho-2023117

ABSTRACT

This paper presents the results from field measurements and household surveys on the severity of indoor mold risk and its impact on respiratory health in a typical unplanned neighborhood of kampungs in Bandung, Indonesia. Mold risk was investigated using fungal risk detectors (n = 102), while air pollution levels were established with total suspended particulate (TSP) and particulate matter (PM2.5) (n = 38). The self-reported prevalence of respiratory diseases was obtained using a questionnaire form (ATS-DLD-78) (n = 599). The results showed that respiratory health problems were higher in the rainy season, particularly among children. Most houses suffered from severe mold risk, primarily due to extreme humid weather conditions, especially during rainy season (97%) where water leakage was prevalent (60%). In addition, the TSP and PM2.5 concentrations exceeded the WHO standards in most kampung houses, where around 58% of the houses recorded higher outdoor mean PM2.5 concentrations than indoors. Further, the path analysis showed that allergies followed by humidity rate and smell, which were affected by window-opening duration, directly impacted children’s respiratory health. Smoking behavior and building-related health problems, due to exposure to outdoor air pollution, affected the respiratory health of those aged 15 years old and over.

6.
Annals of the Faculty of Engineering Hunedoara ; 20(2):89-96, 2022.
Article in English | ProQuest Central | ID: covidwho-1998285

ABSTRACT

The quality of concrete in reinforced concrete structures can be tested either by destructive or non-destructive technique. For structures under use, non-destructive technique is preferred simply because the method affords little or no destruction of the structural elements under investigation. Schmidt Rebound Hammer test was used to assess the reinforced concrete structural elements of two University Hostels labelled A and B. From the investigation of the concrete quality according to IS 13311-2:1992, it was discovered that for the selected elements considered in Hostel A, 89% of the ground floor columns are of fair hard concrete and 11% are of good concrete layer;67% are of very good layer while 33% are of good layer for slab and 3% of the beams are of fair quality concrete while the rest are of good qualities. However, for Hostel B, 8% of the ground columns are of good hard concrete, 78% are of fair hard layer and 14% are of poor concrete layer, while 56% are of good hard layer and 44% are of very good layer for slab and 51% are of good hard layer and 49% are of very good layer for beams. Rapt attention is therefore needed on the columns of Hostel B and to those elements that gave low rebound values so that the structural integrity of the buildings can be sustained to a high degree. Also, because of the variability of the quality of concrete of the assessed structural elements, more non-destructive tests like ultrasonic pulse velocity test should be conducted.

7.
Sustainability ; 14(15):9071, 2022.
Article in English | ProQuest Central | ID: covidwho-1994154

ABSTRACT

The effects of hesperidin and different casings on pH, moisture content, water-holding capacity, and total viable count (TVC) of sausages stored for 171 days were evaluated by principal component analysis (PCA) and discriminant analysis (DA). Sausages stuffed in a modified casing with treatment B (soy lecithin concentration: 1:30, soy oil concentration: 2.5%, lactic acid concentration: 21 mL/kg NaCl [solid], treated time: 90 min) had a significantly lower pH value (6.89 ± 0.01) at d 31 but higher (6.55 ± 0.03) than that of control casings at d 171 (p < 0.05). Hesperidin plays an important role in antimicrobial property that renders the sausages with modified casing by treatment A (soy lecithin concentration: 1:27.5, soy oil concentration: 1.25%, lactic acid concentration: 19.5 mL/kg NaCl [solid], treated time: 75 min) stable (p > 0.05), with the final TVC of 5.03 ± 0.10 log cfu/g. According to the PCA results, water-holding capacity has a positive correlation to pH. Moisture content was the best discriminator for differentiating sausages with control and modified casings, whilst pH was able to discriminate sausages stored after 138 days from other days.

8.
International Journal of Agricultural and Biological Engineering ; 15(3):55-61, 2022.
Article in English | ProQuest Central | ID: covidwho-1934919

ABSTRACT

Food security is one of the key global challenges in this century. In Singapore, our research team has been using novel aeroponic technology to produce fresh vegetables since 1997. Aeroponic systems allow for year-round production of not only tropical, but also sub-tropical and temperate fresh vegetables, by simply cooling the roots suspended in aeroponic systems while the aerial parts grow under tropical ambient environments. It has also been used to investigate the impacts of root-zone CO2 on vegetables by enriching root-zone CO2 while their aerial portions were subjected to constant atmospheric CO2. To compensate for the lack of available land, Singapore also needs to develop a farming system that can increase productivity per unit land area by many-fold. Over the past 10 years, my research team has established a commercially viable LED integrated vertical aeroponic farming system to grow different leafy vegetables under different LED spectra, intensities, and durations in the tropical greenhouse. The results demonstrate that it is possible to increase shoot production and rate of shoot production of leafy vegetables by increasing light intensity and extending the photoperiod under effective LED lighting. Furthermore, temperate vegetable crops such as lettuce were able to acclimate to high light intensity under supplementary LED lights to natural sunlight in the greenhouse. Supplementary LED lightings promote both leaf initiation and expansion with increased photo synthetic pigments, higher Cyt b6f and Rubisco protein contents on a per area basis and thus improve photosynthetic capacity and enhance productivity. Plants sense and respond to changes in their immediate environments (microclimate), manipulating the root zone temperature (RZT) and water supply will impact not only their growth and development but also their nutritional quality. Our on-going research aims to investigate if the nutritional quality of leafy vegetables could be improved under suboptimal RZT and mild water deficit through deficit irrigation. If substantial energy and water savings in urban farming can be achieved without substantial yield penalty but with higher nutritional quality, the amount of water and energy saved can bring substantial benefits to society.

9.
Forests ; 13(5):636, 2022.
Article in English | ProQuest Central | ID: covidwho-1871503

ABSTRACT

The aim of this research was to determine the resistance of acetylated wood against marine biodeterioration in use class 5 for use in temperate waters. The resistance of acetylated radiata pine (Pinus radiata D. Don) on solid and medium-density fiberboard (MDF) panels was compared with untreated wood of European species, such as European beech (Fagus sylvatica L.), sweet chestnut (Castanea sativa Mill.), European oak (Quercus robur L.), and marine plywood. As a reference control, untreated Scots pine (Pinus sylvestris L.) sapwood was used. The field tests were carried out in accordance with EN 275, and started in April 2015. The three Italian exposure sites were Marine of Scarlino private harbor, Port of Genoa, and the Venice Lagoon. Final evaluation in 2021 showed a greater resistance to marine borers of acetylated wood, radiata pine, and beech and MDF panels. However, the untreated European species showed low resistance against marine organisms, with complete decay after the first year of exposure.

10.
Communications Materials ; 3(1), 2022.
Article in English | ProQuest Central | ID: covidwho-1857501

ABSTRACT

The airborne nature of coronavirus transmission makes it critical to develop new barrier technologies that can simultaneously reduce aerosol and viral spread. Here, we report nanostructured membranes with tunable thickness and porosity for filtering coronavirus-sized aerosols, combined with antiviral enzyme functionalization that can denature spike glycoproteins of the SARS-CoV-2 virus in low-hydration environments. Thin, asymmetric membranes with subtilisin enzyme and methacrylic functionalization show more than 98.90% filtration efficiency for 100-nm unfunctionalized and protein-functionalized polystyrene latex aerosol particles. Unfunctionalized membranes provided a protection factor of 540 ± 380 for coronavirus-sized particle, above the Occupational Safety and Health Administration’s standard of 10 for N95 masks. SARS-CoV-2 spike glycoprotein on the surface of coronavirus-sized particles was denatured in 30 s by subtilisin enzyme-functionalized membranes with 0.02-0.2% water content on the membrane surface.The COVID-19 pandemic highlights the importance of materials that block airborne virus transmission. Here, a nanostructured membrane is shown to filter coronavirus-sized particles, while the membrane surface incorporates enzymes that denature the SARS-CoV-2 spike protein within 30 s.

11.
Sustainability ; 14(8):4675, 2022.
Article in English | ProQuest Central | ID: covidwho-1810152

ABSTRACT

The article presents an analysis of the impact of bio-based materials on the environment, with a special focus on polylactic acid (PLA), as it is considered one of the most popular bioplastics in the market. The results show that there are several factors that must be taken into account when choosing the best end-of-life option for this type of material, in agreement with the newly introduced concept of the circular economy, according to the physical–chemical analysis obtained at the end of this study. The ecotoxicity tests showed that all tested materials (PLA spoon, PLA filament, b2w technology bag and cocoa paper tray) could be suitable for incineration with energy recovery without producing dioxines during combustion (chlorine content in all tested materials was below 1.00% w/w). It was also determined that PLA was the material with the highest potential for energy recovery since it presented the highest calorific value and highest carbon content (18.73 MJ/kg and 52.23%, respectively). The biodegradation rate of the different bio-based materials was also tested under different environments during three months, with Baltic Sea water and medium-grain sand being the environments in which the majority of the bio-based materials showed the lowest degradation rates. An additional test in a small-scale electric composter with microbe technology was carried out in order to evaluate the degradation of the studied materials in an environment with controlled conditions, and results showed high values of weight loss for the majority of the bio-based materials (all above 80% weight loss) due to the high temperature that the device could reach during the composting process. Finally, a strategy for providing guidance in selecting routes for the waste management of bioplastics, depending mainly on the available infrastructure and material properties, was proposed as a result of this work. For the case of low- and medium-income countries, an Extended Producer Responsibility (EPR) policy is proposed as a provisional solution to control plastic waste pollution, which should be complemented by regulations and systems aimed at the successful introduction of bioplastics.

12.
Applied Sciences ; 12(8):4001, 2022.
Article in English | ProQuest Central | ID: covidwho-1809671

ABSTRACT

Given recent worldwide environmental concerns, biodegradability, antibacterial activity, and healing properties around the wound area are vital features that should be taken into consideration while preparing biomedical materials such as wound dressings. Some of the available wound dressings present some major disadvantages. For example, low water vapor transmission rate (WVTR), inadequate exudates absorption, and the complex and high environmental cost of the disposal/recycling processes represent such drawbacks. In this paper, starch/polyvinyl alcohol (PVA) material with inserted nano-sized zinc-oxide particles (nZnO) (average size ≤ 100 nm) was made and altered using citric acid (CA). Both ensure an efficient antibacterial environment for wound-dressing materials. The film properties were assessed by UV–Vis spectrometry and were validated against the UV light transmission percentage of the starch/ polyvinyl alcohol (PVA)/ zinc-oxide nanoparticles (nZnO) composites. Analyses were conducted using X-ray Spectroscopy (EDX) and scanning electron microscopy (SEM) to investigate the structure and surface morphology of the materials. Moreover, to validate an ideal moisture content around the wound area, which is necessary for an optimum wound-healing process, the water vapor transmission rate of the film was measured. The new starch-based materials exhibited suitable physical and chemical properties, including solubility, gel fraction, fluid absorption, biodegradability, surface morphology (scanning electron microscopy imaging), and mechanical properties. Additionally, the pH level of the starch-based/nZnO film was measured to study the prospect of bacterial growth on this wound-dressing material. Furthermore, the in vitro antibacterial activity demonstrated that the dressings material effectively inhibited the growth and penetration of bacteria (Escherichia coli, Staphylococcus aureus).

13.
Atmospheric Chemistry and Physics ; 22(7):4355-4374, 2022.
Article in English | ProQuest Central | ID: covidwho-1776521

ABSTRACT

Nitrate aerosol plays an increasingly important role in wintertime haze pollution in China. Despite intensive research on wintertime nitrate chemistry in recent years, quantitative constraints on the formation mechanisms of nitrate aerosol in the Yangtze River Delta (YRD), one of the most developed and densely populated regions in eastern China, remain inadequate. In this study, we identify the major nitrate formation pathways and their key controlling factors during the winter haze pollution period in the eastern YRD using 2-year (2018–2019) field observations and detailed observation-constrained model simulations. We find that the high atmospheric oxidation capacity, coupled with high aerosol liquid water content (ALWC), made both the heterogeneous hydrolysis of dinitrogen pentoxide (N2O5) and the gas-phase OH oxidation of nitrogen dioxide (NO2) important pathways for wintertime nitrate formation in this region, with contribution percentages of 69 % and 29 % in urban areas and 63 % and 35 % in suburban areas during the haze pollution episodes, respectively. We further find that the gas-to-particle partitioning of nitric acid (HNO3) was very efficient so that the rate-determining step in the overall formation process of nitrate aerosol was the oxidation of NOx to HNO3 through both heterogeneous and gas-phase processes. The atmospheric oxidation capacity (i.e., the availability of O3 and OH radicals) was the key factor controlling the production rate of HNO3 from both processes. During the COVID-19 lockdown (January–February 2020), the enhanced atmospheric oxidation capacity greatly promoted the oxidation of NOx to nitrate and hence weakened the response of nitrate aerosol to the emission reductions in urban areas. Our study sheds light on the detailed formation mechanisms of wintertime nitrate aerosol in the eastern YRD and highlights the demand for the synergetic regulation of atmospheric oxidation capacity and NOx emissions to mitigate wintertime nitrate and haze pollution in eastern China.

14.
Energies ; 15(5):1936, 2022.
Article in English | ProQuest Central | ID: covidwho-1736870

ABSTRACT

The climate crisis is one of the most important problems today. In the process of human building, the use of cement, steel, and other industrial materials in the process of building construction and recycling has brought a huge burden to the natural environment. Earth is one of the oldest building materials, its availability and insulation make it an excellent constructive solution in human history. Among several existing earth construction techniques, rammed earth is one of the most relevant. In this paper, a numerical model of the rammed earth folk house in Mianyang was established, and an experimental device was built to verify it. With the typical meteorological year data of Mianyang in northwest Sichuan, the heat and moisture transfer in rammed earth wall, as well as the indoor thermal and moisture environment were numerically simulated. The results show that the rammed earth wall weakens the temperature fluctuation of the inner surface of the wall and makes the peak temperature of the inner surface of the wall lag the outer surface. The relative humidity in the center of the rammed earth wall can be maintained at about 60%, both in winter and summer. The moisture absorption and desorption capacity of rammed earth walls without inner decorative materials is about three times that of gypsum board, and the use of a waterproof coating will render the rammed earth wall almost unable to adjust the indoor relative humidity. Additionally, the use of decorative materials will increase the fluctuation range of indoor relative humidity and the risk of mold breeding.

15.
IOP Conference Series. Earth and Environmental Science ; 980(1):012037, 2022.
Article in English | ProQuest Central | ID: covidwho-1730602

ABSTRACT

The fishing communities in Sungai Rasau village, South Kalimantan, Indonesia, have several joint business groups that mostly process their fish catch into salted fish products and shrimp paste for sale in the market. The fish drying technique still uses traditional methods that rely on sunny weather, this is not effective because the weather is difficult to predict due to climate change globally. This means that high rainfall affects fish drying production activities. If left unchecked, this certainly results in a decrease in the quantity and quality of salted fish production and affects their income and welfare. To maintain and improve the quality of raw materials for fisheries production, the solution is the use of appropriate technology, namely making salted fish processing equipment or dryers that are energy efficient and not influenced by weather factors such as rain. Using this tool can improve the quality and quantity of production. The form of activity methods carried out includes (1) coordination with related parties to foster local fishing groups;(2) identifying problems and determining solutions;(3) solar fish dryer design;(4) making efficient technology fish dryers that effectively and efficiently utilize solar energy. At the time of implementation of the dryer, the measurement of water content using TDS obtained results that the water content of mackerel has been reduced to about 10%

16.
Horticulturae ; 7(12):517, 2021.
Article in English | ProQuest Central | ID: covidwho-1598761

ABSTRACT

Effects of drought and aerosol stresses were studied in a factorial experiment based on a Randomized Complete Design with triplicates on two ornamental shrubs. Treatments consisted of four levels of water container (40%, 30%, 20%, and 10% of water volumetric content of the substrate) and, after 30 days from experiment onset, three aerosol treatments (distilled water and 50% and 100% salt sea water concentrations). The trial was contextually replicated on two species: Callistemon citrinus (Curtis) Skeels and Viburnum tinus L. ‘Lucidum’. In both species, increasing drought stress negatively affected dry biomass, leaf area, net photosynthesis, chlorophyll a fluorescence, and relative water content. The added saline aerosol stress induced a further physiological water deficit in plants of both species, with more emphasis on Callistemon. The interaction between the two stress conditions was found to be additive for almost all the physiological parameters, resulting in enhanced damage on plants under stress combination. Total biomass, for effect of combined stresses, ranged from 120.1 to 86.4 g plant−1 in Callistemon and from 122.3 to 94.6 g plant−1 in Viburnum. The net photosynthesis in Callistemon declined by the 70% after 30 days in WC 10% and by the 45% and 53% in WC 20% and WC 10% respectively after 60 days. In Viburnum plants, since the first measurement (7 days), a decrease of net photosynthesis was observed for the more stressed treatments (WC 20% and WC 10%), by 57%. The overall data suggested that Viburnum was more tolerant compared the Callistemon under the experimental conditions studied.

17.
Fermentation ; 7(4):265, 2021.
Article in English | ProQuest Central | ID: covidwho-1594433

ABSTRACT

The primary objective of this research is to study ways to increase the potential of energy production from food waste by co-production of bioethanol and biomethane. In the first step, the food waste was hydrolysed with an enzyme at different concentrations. By increasing the concentration of enzyme, the amount of reducing sugar produced increased, reaching a maximum amount of 0.49 g/g food waste. After 120 h of fermentation with Saccharomyces cerevisiae, nearly all reducing sugars in the hydrolysate were converted to ethanol, yielding 0.43–0.50 g ethanol/g reducing sugar, or 84.3–99.6% of theoretical yield. The solid residue from fermentation was subsequently subjected to anaerobic digestion, allowing the production of biomethane, which reached a maximum yield of 264.53 ± 2.3 mL/g VS. This results in a gross energy output of 9.57 GJ, which is considered a nearly 58% increase in total energy obtained, compared to ethanol production alone. This study shows that food waste is a raw material with high energy production potential that could be further developed into a promising energy source. Not only does this benefit energy production, but it also lowers the cost of food waste disposal, reduces greenhouse gas emissions, and is a sustainable energy production approach.

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