Development And Validation of An Eco-Friendly and High-Throughput HPLC Method To Quantify Pyrethroid and Pyriproxyfen in Long-Lasting Insecticide-Treated Nets

Long-lasting insecticide-treated nets (LLINs) are essential to preventing malaria transmission. The LLINs should last for at least three years, even after repeated washings. Currently, tracking insecticides in LLINs is cumbersome, costly, and requires specialized equipment and hazardous solvents. We therefore developed a low-resource, high-throughput method for detecting insecticides in LLINs. In order to extract insecticides from polyethylene, LLIN samples were heated for 45 minutes at 85oC in 1-propanol-heptane containing dicyclohexylphthalate as an internal standard. Sample size was reduced to ~0.2 g for reduced extraction volume, which is 10% less than what was recommended. We optimized HPLC chromatographic conditions to assess pyrethroid and pyriproxyfen content in polyethylene-based LLINs. The method is capable of quantifying levels ≥ 0.0015% permethrin, 0.00045% alpha-cypermethrin and 0.00025% pyriproxyfen (w/w) in polyethylene, allowing tracking the insecticides before and after LLINs use. A variety of LLINs can be evaluated with this method, including those with 1% pyriproxyfen (pyriproxyfen-LLIN) or 2% permethrin (Olyset® Net), 1% pyriproxyfen and 2% permethrin (Olyset® Duo), or 0.55% pyriproxyfen combined with 0.55% alpha-cypermethrin (Royal Gaurd®). Analysis of 120 samples (40 nets) per run can be done with high precision and accuracy, reducing labour time and costs whilst reducing the environmental impact of organic solvents.

Characteristics of Pressure Relief Gas Extraction in the Protected Layer by Surface Drilling in Huainan

To study the behavior of gas extraction from the protected layer by surface drilling, the common characteristics of gas extraction concentration and gas extraction quantity are summarized through the collection of key parameters of surface drilling and a combination of data and figures, with the background of 11−2 coal protection 13−1 coal in the Huainan mining area. The research results show that the flow of pressure relief gas extraction of the protected layer by surface drilling has three stages: a rising period, stable period, and decay period. When the extraction processes of multiple surface wells on the same working face are coordinated, the extraction flow is superimposed, and the extraction volume of surface drilling shows an increasing trend and fluctuates with the location of the drilling. The extraction flow rate before ground drilling is relatively small, and the extraction flow rate increases after ground drilling. This behavior is further confirmed by field observation of mining changes in the protective layer and the expansion and deformation of the protected layer. The periodic variation in the surface drilling and extraction quantity is affected primarily by the mining movement of the working face of the protective layer. Specifically, it is affected by factors such as the mining progress of the working face of the protective layer, mining height, degree of compacted goaf, degree of pressure relief of the protected layer, original gas content, and other measures taken to extract the protected layer.

ULTRASOUND ASSISTED BIO-DYEING OF SOME TEXTILE MATERIALS WITH BLACK CARROT (DAUCUS CAROTA L.) EXTRACT

"This study has been conducted to find out whether black carrot extract can be used as a dyestuff to dye textile materials. For this purpose, the two most widely used textiles (namely, cotton and wool) have been selected. The extractions from the black carrot were performed directly in the dyebath. An ultrasonic bath at 80 °C for 60 minutes was used to increase extraction efficiency. All the dyeing processes were carried out at 100 °C for 60 minutes, both with and without some metal salts, using two different dye concentrations in 1:1 and 1:10 ratios (material weight:dye extraction volume). Six different metal salts, i.e. K2Cr2O7, CuSO45H2O, FeSO47H2O, SnCl22H2O, ZnSO47H2O, KAl(SO4)2.12H2O, were used in the dyeing processes, according to pre- and simultaneous mordanting methods. After the dyeing processes, the dyed samples’ CIE L*a*b* and color efficiency K/S values were determined by spectrophotometry. The SEM and FTIR data of the fabrics were collected and evaluated at the end of the trials as well. At the same time, perspiration, rubbing, washing and light fastness values of the dyed materials were also assessed. Acceptable fastness test results were obtained for the dyed samples. The findings of the study indicated that the dyeability performance of wool and cotton fabrics with black carrot (Daucus carota L.) extract could be greatly influenced by the mordant used and its application method."

Hydrogeological Risk Assessment for Groundwater Conservation in the Northeastern Slope Area of Mount Arjuno, Pasuruan Regency, East Java, Indonesia

The northeastern slope of Mount Arjuno, Pasuruan district, East Java province, Indonesia represents a vast and good groundwater resource quality, generally be exploited by some companies for drinking water industries. Water unbalance and quality degradation is presumed to arise because groundwater extraction volume is getting bigger but less control by the regency authority. This study is to figure out the geologic condition and hydrogeological system, conduct groundwater exploitation risk assessment, and develop a conservation program. The study results show that the study area's geomorphological units can be divided into the volcanic summit, volcanic slope, fluvial plain, and anticlinal hills. The lithology comprises sandstone, breccia, and andesite lava of Mount Arjuno and Mount Welirang. The geological structures are anticline, normal fault, and lateral slip fault. Hydrologically, there are three watersheds, including Lumbangrejo, Ketanireng, and Prigen watersheds. The aquifers comprise unconfined to semi-confined aquifers with fissures and intergranular porosity. Based on risk assessment valuation, Pecalukan village of the Ketanireng watershed and Lumbangrejo village of the Lumbangrejo watershed are categorized as very high groundwater vulnerability zones, Karangrejo and Sukoreno villages of the Lumbangrejo watershed, Kedungringin, Kepulungan, and Gunungsari villages of the Ketanireng watershed are categorized as medium vulnerability zone. While, Ngorong village of the Lumbangrejo watershed, Gempeng, Oro-Ombo, Kalisat, and Dukuhsari villages of the Prigen watershed belong to the low vulnerability zone. The proposed conservation programs involve profitable water use safety campaigns, domestic waste, and industrial wastewater management, agricultural activities controlling, sandstone mining regulation, and reforestation.

Producing Drink like Grafted Milk from Chickpeas and Evaluation of its Qualitative Properties

The present study aimed to study the possibility of producing a drink that looks like grafted milk by using chickpeas and evaluate its physical, chemical, microbial, and sensory properties. The result showed the superiority of F treatment (soaking 100 grams of chickpeas at the refrigerator temperature 4ºC for 12 hours) over the rest seven treatments in extraction efficiency, which was 70%, while, it was 50.5% in H treatment (soaking 100 grams of chickpeas in the heated water at 60ºC for 30 minutes). The highest value of the product density was after water and flavorings addition in the D treatment (soaking 100 grams chickpeas in 0.05 soda solution at 60ºC for 30 minutes), and it was 0.97 g cm-3, compared with the lowest density 0.57 g cm-3 in A treatment (soaking 100 grams chickpeas in 0.05 soda solution at room temperature 25ºC for 12 hours). pH values were highest in A treatment compared with the other treatments, and its value was 7.66 in the 1st and 2nd day, after dissolving in a refrigerator at 4ºC, and then, for 5 minutes at room temperature 30ºC. The lowest value in the D treatment was 6.45 on the 1st day, and 6.87 on the 2nd day in the G treatment. On the 3rd day, the highest pH value was 7.13 in the D treatment, and the lowest value 6.79 was in the E treatment. pH highest value was 6.2 on the 4th day in A treatment. From the last results, it may be concluded that F treatment was the best in extraction efficiency, the final product density, and less total bacterial number, after dissolving for 5 days at refrigerator temperature 4ºC, and then, at room temperature 30ºC for 3 and 48 hours incubation. The best extraction volume and pH were in A treatment.

Sand mining in the Mekong Delta revisited - current scales of local sediment deficits

The delta of the Mekong River in Vietnam has been heavily impacted by anthropogenic stresses in recent years, such as upstream dam construction and sand mining within the main and distributary channels, leading to riverbank and coastal erosion. Intensive bathymetric surveys, conducted within the Tien River branch during the dry and wet season 2018, reveal a high magnitude of sand mining activities. For the year 2018, an analysis of bathymetric maps and the local refilling processes leads to an estimated sand extraction volume of 4.64 $$\pm $$± 0.31 Mm$${}^{3}$$3/yr in the study area, which covered around 20 km. Reported statistics of sand mining for all of the Mekong’s channels within the delta, which have a cumulative length of several hundred kilometres, are 17.77 Mm$${}^{3}$$3/yr for this period. Results from this study highlight that these statistics are likely too conservative. It is also shown that natural sediment supplies from upper reaches of the Mekong are insufficient to compensate for the loss of extracted bed aggregates, illustrating the non-sustainable nature of the local sand mining practices.

Groundwater Flow Model and Statistical Comparisons Used in Sustainability of Aquifers in Arid Regions

Groundwater provides the most important of the water resources used in the maintenance of communities in arid and semi-arid regions. In these areas, the usage of deep wells with motorized pumps in combination with the lack of effective regulatory policies and high human population growth (increase the water demand) impact the quality of the groundwater. This is especially the case for the San José del Cabo aquifer, in Baja California Sur. In the present study the groundwater flow system is analyzed in order to recognize the impact from variations in groundwater extraction and recharge on the phreatic levels and discharge values. In order to achieve this goal, a groundwater model was generated using the MODFLOW program. Different scenarios of extraction and recharge were calculated, based on different estimations of population growth. All the scenarios result in decreasing groundwater levels. As an important result, a relationship between the phreatic level and the extraction volume was found for the middle zone of the aquifer, where an average annual decrease of 0.5 m was observed from every 5 × 106 m3 additional extraction volume. This zone is up to three times more susceptible to changes in extraction values than the southern zone. As the results show, the San José del Cabo aquifer is in a fragile state where an increment in extraction is not an option without the use of remediation technics or new sources for water supply.

The Carbon Benefit of Thinned Wood for Bioenergy in Taiwan

Forest thinning is a way to make room for the growth of remaining trees, and the thinned wood can serve as a fuel for bioenergy in order to combat climate change. Using thinned wood for bioenergy can substitute for fossil fuel energy, resulting in potential carbon benefit. Since not all thinned wood can be transported out of the forest for processing, the extraction ratio (extraction volume/thinning volume) is an important variable for determining the net carbon benefit. This study investigated 52 forest-thinning sites in Taiwan. The extraction ratio was estimated to explore the benefit of thinned wood used as bioenergy. Cross analysis was adopted to find the relationships between site/species attributes and extraction ratio. The factors included age class, thinning method, land use classification, and species. Key variables included thinning volume, extraction volume, and extraction ratio. Statistical analysis was then applied to identify the significant differences. The analysis shows that the extraction ratio of thinned wood is 57.12%. The research outcomes could provide valuable information for green-energy policy making in Taiwan.

Using Underwater Shockwaves for the Development of Processing Devices for Plant Materials

In this study, we have established a novel pretreatment system that improves the juice extraction volume and nutritional value of plant material using underwater shockwaves. The optimum treatment conditions for plant materials were obtained by conducting batch experiments using simple-structured underwater shockwave treatment equipment. From these results, a continuous underwater shockwave processing device was designed. Moreover, we have been demonstrated the applicability and reliability of underwater shockwave pretreatment in improving the yield of functional ingredients and fruit juice from plants. The instantaneous high-pressure dynamic control using underwater shockwaves is applicable to a wide range of extraction processes such as extraction of juices or ingredients from other naturally occurring foods and medicinal plants.