Nylon Nets Research Articles

High-Throughput Screening System Evaluation of Andrographis paniculata (Burm.f.) Extracts and Their Fractions against Mosquito Vectors.

Infectious diseases that cause illness and/or death in humans can be contracted from mosquito bites. A viable and alternate method of personal protection that can lower the danger of human exposure to mosquito-borne diseases is the use of plant-based repellents. Using a high-throughput screening system, the current work examined the toxicity, contact irritancy, and spatial repellency of Andrographis paniculata crude extract and its fractions against Aedes aegypti, Anopheles minimus, and An. dirus. Five fractions (i.e., F1, F2, F3, F4, and F5) were separated from the crude extract by column and thin layer chromatography and analyzed using high-performance liquid chromatography and mass spectrometry. The major active compounds identified from F3 and F5 were 4-deoxy-11,12-didehydroandrographolide and andrographolide. Three concentrations (1.0, 2.5, and 5.0%) for each of the crude extracts and the five fractions were individually impregnated on nylon netting strips and evaluated against the three mosquito species. Results showed that the highest contact irritancy was elicited by the crude extract at 5% concentration against Ae. aegypti (43.70% escaped). Results of the spatial activity index (SAI) showed that fractions F3 and F5 at 2.5% demonstrated the strongest repellency against Ae. aegypti (SAI = 0.84) and An. minimus (SAI = 0.83), respectively. Both the crude extract and its components did not cause any knockdown or mortality. These findings suggest that fractionation of A. paniculata extracts is valuable in assessing their spatial repellent efficacy against mosquitoes. Fractions F3 and F5 hold promise as natural mosquito repellents and could contribute to developing effective mosquito control strategies.

Ion migration mechanism of electrochemical water softening in dual-chamber reactors and their performance for real circulating cooling water

Electrochemical water softening studies often use ion exchange membrane (IEM) reactors. However, their practical application is limited because of inevitable cathodic scaling. To overcome this challenge, one necessary approach is to understand the ion migration mechanism in the typical IEM reactor. In this study, we used operando visualization to reveal that the divider such as IEM or nylon nets was essential to confine the neutralization reaction between H+ and OH−. Ca2+ and Mg2+ may transfer from the anode chamber through the divider into the cathode chamber via electromigration. Using mesh electrodes instead of plate electrodes, the total hardness removal in the cathode chamber and anode chamber was 94.2% and 92.5%, respectively. The high removal rate was attributed to H2 microbubbles produced by cathodic water electrolysis, which drove OH− ions diffusion into solution and sequentially strengthened the nucleation of scale crystals in solution rather than on the cathode surface. On the basis of the above ion migration mechanism, the revolutionized reactor with mesh electrode module and nylon-net divider exhibited good performance in softening real circulating cooling water, and the total hardness removal exceeded 93.1% during 30 h running. These results open new horizons for improving the practicability of electrochemical water softening.

Ghost Fishing Threatens Biodiversity in an African Great Lake

We conducted an investigation into ghost fishing, a phenomenon in which abandoned fishing equipment remains operational for extended durations, in the southern region of Lake Tanganyika, Republic of Zambia. The perils associated with ghost fishing have achieved international recognition; however, there exists a conspicuous dearth of scholarly investigations in particular regions, notably inland aquatic environments and developing countries. Employing scuba diving for field observations, we discovered that ghost fishing was solely evident in monofilament nylon nets, despite the presence of four different net types in the littoral area of the lake. Notably, endemic crabs Platythelphusa armata and P. maculata from Lake Tanganyika constituted 65.2% of the organisms captured by abandoned nets, with the remainder comprising various fish species. The number of captured organisms exhibited a dependence on the interplay between the length and mesh size of the abandoned nets, indicating that the risk of ghost fishing is heightened when both net and mesh size are substantial. Furthermore, we encountered predatory Spiny Eels Mastacembelus moorii ensnared in nets around their jaws and teeth. Intriguingly, the digestive tract of one of the Spiny Eels contained a partially digested cichlid species entangled in the same nets, strongly suggesting the occurrence of secondary ghost fishing.

Management Technique Against Spodoptera Exigua (Hübner) in the Different Elevation of Shallot

Spodoptera exigua (Hübner) (beet armyworm) as the destructive insect pest in shallot. The purpose of the research is to determine difference of S. exigua management techniques based elevation in two different plantation. The research was conducted by collected primary data from shallot farmers in Anggeraja District (Mataran 650 m asl and Pekalobean 840 m asl) and Baraka District (Perarian 1.014 m asl and Parinding 638 m asl). The two places used in research is the center of shallot plantation in Enrekang Regency, South Sulawesi. The data was obtained by survey used 15 shallot farmers in each village. The results showed the control techniques different according to the elevation. S. exigua controlled by nylon nets only in areas < 700 m asl (Mataran 53% and Parinding 27%). In areas with elevation > 700 m asl (result of light trap in Mataran by 87% and Parinding by 80%). In the elevation > 700 m asl (result of light trap in Pekalobean about 100% and Perangian 0%). The mechanical control techniques by squeezing insect pest eggs at elevation of > 700 m asl (Pekalobean 93% and Perangian 6%), elevation of < 700 m asl (Mataran and Parinding both showed 60%). Conclusion of research, the control techniques different based on the elevation of shallot plantation.

Use of nylon net packing to increase the survival time of cultured mussels

Mussels survive a few days after harvesting, limiting the trade of these animals when alive. The study evaluated the effect of nylon net packing on the survival and shelf life of Perna perna mussels farmed in Brazil. Thirty samples containing 10 or 11 market-size mussels were stored in an incubator at 4°C for four days, half packed with nylon netting and the other half maintained within opened containers. The experiment analyzed the following parameters daily: survivorship, intervalvar fluid loss, total volatile bases, pH, and mesophilic and psychrotrophic bacteria counts. By the end of the assay, chemical and microbiological parameters were all acceptable for human consumption. All packed mussels survived up to the second day of storage, while the control group recorded an average survival of 29.7% in the same period. Packed mussels survive longer, probably because the tight net prevents animals from losing liquid by maintaining their shell valves closed during storage. This packaging method extends the shelf life of live products and improves the potential trading live mussels to consumer centers far from marine farms.

Sinking Behavior of Netting Panels Made with Various Twine Materials, Solidity Ratios, Knot Types, and Leadline Weights in Flume Tank

Netting is an important component of fishing gear design, and its ability to sink determines the effectiveness of fishing gears such as purse seines, falling nets, and stick-held nets. Therefore, it is crucial to thoroughly investigate the sinking parameters (sinking depth and sinking speed) of the netting panel as a function of the leadline weights using various twine materials, knot types, and solidity ratios. In this study, a generalized additive model (GAM) was utilized to analyze the impact of each factor on the sinking performances of the netting. The results revealed that the sinking depth of the netting was positively correlated with sinking time and leadline weight. However, the netting featured a maximum sinking depth limit, indicating that the sinking depth would not increase beyond a leadline weight of 69.5 g. During the initial phase of the sinking process, the sinking velocity of each netting panel initially increased but gradually decreased over time. The incorporation of a leadline weight reduced sinking time. Thereby, polyester netting exhibited the shortest average sinking time. A comparison of netting types with similar solidity ratios showed that the maximum sinking depth of the nylon netting was 13.20% and 10.11% greater than that of polyethylene and polyester nettings, respectively. In addition, nylon nets’ time average sinking speed was 64.58% and 4.62% greater than that of polyethylene and polyester nettings, respectively. The analysis of the GAM model clearly showed that the leadline weight has a significant effect on the netting sinking speed and depth. To ensure that the netting can reach its maximum sinking speed, it is strongly recommended to use nylon and polyester nettings with a low solidity ratio, i.e., a lower twine diameter and greater mesh size with a higher leadline weight, when constructing fishing gear such as purse seines with higher net leadline weights.

ON THE RESULTS OF A COMPARATIVE ANALYSIS OF THE CATCHABILITY OF TRADITIONAL NYLON NETS AND NETS MADE OF SYNTHETIC M ONOFILAM ENTS IN THE MIDDLE CASPIAN

The article highlights the problems associated with the restriction in the Republic of Kazakhstan of the use of synthetic nylon or other polyamide monofilaments and other synthetic monofilaments (hereinafter synthetic monofilaments) with a thread diameter of less than 0.5 millimeters [1]. The results of a comparative analysis of the catchability of traditional nylon nets and nets made of synthetic monofilament are presented.In order to increase the catches of underutilized fish stocks, including mullet in the Kazakh sector of the Caspian Sea, recommendations were given on the possibility of allowing the use of a network made of synthetic monofilaments in fixed fishing areas of the Caspian Sea within the Mangystau region in a pilot procedure.The study was funded by the Ministry of Ecology and Natural Resources of the Republic of Kazakhstan (Grant no. BR 10264205).

Red Seaweed Porphyra spp. (Bangiales) from Urimessing Waters of Ambon Island - Maluku

A study on the cultivation of Porphyra spp. has been carried out in the waters of Ambon Island. This plant is in great favor with local communities but has not been able to meet broader demands. The purpose of this research was to look into the future of mass culture. In the splashing zone, which is about 10 m above sea level, samples of gametophyte foliose or thalli were taken. The thallus was brought to the laboratory and maintained in a 100-liter container. During the rearing period, the thallus released spermatia and fertilized carpogonia. Carpogonia develop into carposporangia and release zygotospores outside the thallus. A small zygotospore develops into a large carpospore. Carpospores are the forerunners of new sporophytes if they find the correct substrate. In the laboratory, the nacre layer of pearl oyster shells was used to replace the natural substrates. Carpospores attached to the nacre layer germinated and grew into conchocelis. The conchocelis then develops the conchosporangia outward, followed by the release of the conchospores. Conchospores are a source of new thalli grown on polyethylene nylon nets. Conchospores that grew into new thalli on nylon nets were then moved to their natural environments so they could keep growing.

Spatial and temporal regulation of homogeneous nucleation and crystal growth for high-flux electrochemical water softening

Electrochemical softening is an effective technology for the treatment of circulating cooling water, but its hardness removal efficiency is limited because that nucleation and growth of scale crystals depended on cathode surface. In this study, a novel method was proposed to break through this limit via spatiotemporal management of nucleation and growth processes. A cube reactor was divided into cathodic chamber and anodic chamber via installing a sandwich structure module composed of mesh cathode, nylon nets, and mesh anode. Using this continuous-flowing electrochemical reactor, OH ̄ generated by water electrolysis was rapidly pushed away from cathode surface by water flow and hydrogen bubbles movement. As a result, a wide range of strongly alkaline regions was rapidly constructed in cathodic chamber to play a nucleation region, and homogeneous nucleation in liquid phase replaced heterogeneous nucleation on cathodic surface. Furthermore, the growth process of scale crystals in alkaline regions was monitored in situ. It took only 150 s of residence time to grow to 500 nm, which may be easily separated from water by a microfiltration membrane. With this new method, the precipitation rate was 290.8 g/(hˑm2) and corresponding energy consumption was 2.1 kW·h/kg CaCO3, both were superior to those reported values. Therefore, this study developed an efficient electrochemical softening method by spatial and temporal regulation of homogeneous nucleation and crystal growth processes.

Analysis of Environmentally Friendly Fishing Equipment in Pasar Bantal Village Teramang Jaya District Mukomuko Regency

Environmentally friendly fishing gear is a fishing gear that does not have a negative impact on the environment, such as not damaging the bottom of the water. There are 4 fishing gears that are often used by the people of Pasar Pillow Village, Teramang Jaya District, namely longline fishing rods, shrimp trawls, millennium nets and nylon nets. Research on the analysis of environmentally friendly fishing gear was carried out in April – May 2022 in Pasar Pillow Village, Teramang Jaya District, Mukomuko Regency. This study aims to analyze environmentally friendly fishing gear (API) in Pasar Pillow Village, Teramang Jaya District, Mukomuko City. The method used is the survey method. Collecting data using observation, interviews and documentation methods. The results of the research data were analyzed by descriptive method. The categories of environmentally friendly fishing gear used by Pillow Market fishermen are longline fishing rods, nylon nets, and millennium nets. The fishing gear that is not environmentally friendly is the shrimp trawl.Keywords: Fishing gear, environmentally friendly, Pasar Bantal Village, Mukomuko

Litter decomposition in a remnant of Atlantic Rain Forest and bamboo dominance

Aim of study: We compared the decomposition rate of the accumulated litter, the stock, and the return of nutrients to the soil, between an area dominated by bamboos in the understory and an area where this dominance does not occur. Area of study: Fontes do Ipiranga State Park, an Urban Fragment of Atlantic Forest at the Municipality of São Paulo, Southeastern Brazil. Materials and methods: The decomposition rates were measured over one year (0, 3, 6, 9, and 12 months), avoiding litter addition through nylon nets over the soil. The collected material was separated into the following fractions: bamboo leaves and branches (bamboo material); other leaves and branches (other material); very decomposed material not identifiable (unidentifiable). The content of macro (N, P, K, Ca, Mg, and S) and micronutrients (B, Cu, Fe, Mn, and Zn) were determined. Main results: The litter accumulated was significantly higher in the mature area than in the bamboo area. The decomposition rates did not differ significantly between the two areas. Except for K and Mn, the concentrations of macro and micronutrients were equal to or greater in the mature forest. Research highlights: Unlike reported in other areas, there is no greater litter accumulation in the bamboo-dominated understory nor a slower decomposition rate. The nutrient content is lower in the bamboo-dominated disturbed area.

Experimental study of the behaviour of a circular gravity cage in linear waves

Experiments are conducted in a flume to study the motions and the wake behind a circular gravity cage under linear waves. The gravity cage model is built with high-density polyethylene pipes and nylon nets. Wave heights and periods are measured by wave gauges both upstream and downstream. Supports are used above the flume to fix the gauges and to connect the cage model. It is found that the cage behaves differently under short and long waves. The relative motion between the floating cage and the water surface is large under short waves. It can be observed clearly how the short waves pass over the collar. On the other hand, the collar just rides on long waves without apparent relative motion. The wave height is reduced when short waves pass the cage, while the wave height reduction under long waves is too small to be measured. The effect of the cage diameter, the collar cross-section, the bottom weight and biofouling is also studied. Generally speaking, larger and heavier cages have a greater impact on waves.

An in-situ approach to cyanobacterial harmful algal blooms degradation of microcystin-LR cyanotoxins using TiO2 photocatalysts coated on nylon mesh supports

Dispersed and immobilized photocatalytic titanium dioxide (TiO2) nanoparticles were investigated for the removal of microcystin-LR (MC-LR) cyanotoxin in water. Dispersed TiO2 concentrations (0.25 g/L, 0.025 g/L, 0.0025 g/L, and 0 g/L) were compared to TiO2 coated on nylon net supports and uncoated nylon nets to determine MC-LR degradation performance. Adsorption of MC-LR onto dispersed TiO2 was tested for 1 h prior to ultraviolet (UV) light exposure, and the maximum adsorption observed was 1%. With UV exposure, 0.25 g/L dispersed TiO2 degraded MC-LR by 99% over a 2-hour time period, while 0 g/L, 0.0025 g/L, and 0.025 g/L TiO2 did not cause significant MC-LR removal. TiO2 nets spray coated 2x, 5x, and 8x with Nafion-TiO2 composite were tested for stability, where the 2x and 8x spray coated nets lacked attachment and stability compared to the 5x coated net. MC-LR adsorption testing on uncoated and 5x coated TiO2 nets resulted in 0% and 13% adsorption, respectively. The 5x coated TiO2 net removed MC-LR by 96%, 64%, and 10% for UV, indirect UV, and no UV exposure over 2 h. MC-LR removal by dispersed 0.25 g/L TiO2 and 5x coated TiO2 nets fit pseudo first-order kinetics, where the rate constants were k = 0.0375 min-1 and k = 0.0264 min-1 for dispersed TiO2 and 5x coated TiO2 nets, respectively. Overall, the study indicated TiO2 photocatalysts coated on nylon supports are comparable to dispersed TiO2 and provide an immobilization approach for in-situ MC-LR removal by TiO2 nanoparticles.

NYLON REINFORCEMENT CEMENT SHEET ON INDUSTRIAL BUILDING

This paper investigated the study of Nylon Reinforced Cement sheets in civil engineering. Nylon has many exclusive properties that it makes suitable for combination with cement mortar. In this, nylon-reinforced cement sheet properties, nylon nets, specifications and construction procedures are studied. The purpose of this paper was to investigate the comparative study between sheets reinforced with nylon cement and regular asbestos sheeting. Because of its wide variety of unusual structures, nylon is excellent cement mortar additive. Nylon material has a high melting point, is chemically resistant, and is stable an alkaline area of mud. It also has a low price. In this process, nylon-reinforced cement sheets are cast, then under various tests, your results compared to those obtained using regular asbestos sheets. Nylon is a readily available non-reactive material that can be used in cement concrete as fiber amplification. This study shows a comparison of the effect of OPC and PCC as well as the use of nylon fiber on the improved durable condition, which was ultimately reflected in the lifetime of the structure. Have supplementary cementations materials, nylon-reinforced PCC exhibits better properties. In addition, electrical induction from the Rapid Chloride Penetration Test (RCPT) and chloride migration coefficient The Rapid Migration Test (RMT) is designed to obtain the optimum nylon fiber content.

Seasonality of the feeding behavior and condition factor of Anchovia surinamensis in the floodplains of the Madeira River (Rondônia, Brazil)

The Anchovia surinamensis (Clupeiformes: Engraulidae) is known in Brazil as "sardinha-do-gato” and exists in the floodplains throughout Latin-America. It is highly appreciated by the Amazonian riverine communities as a source of animal protein. In this study, we analyzed the dietary preferences and abiotic parameters that influence the condition factor of A. surinamensis that inhabit Cujubim Lake during periods of drought and flood. A total of 105 specimens were captured using three batteries of monofilament nylon nets (measuring 20 m long, 2.5 m high, 40, 60, 80 and 100 mm mesh, measured between opposite knots). The nets were arranged in pre-established positions within the lake and inspected at the times of 18:00, 00:00, 06:00 and 12:00 h. This methodology was utilized to obtain the largest range of fish sizes and to avoid the influence of the nictimeral factor. The results of the analysis of the stomach contents of the individuals confirmed that the species is planktivorous and consumes mainly cladocera and bivalves in the Cujubim Lake, which indicates that there is good food availability in the lake. Our results also demonstrate that, among the physicochemical parameters of the water in Cujubim Lake, pH was the one that most affected the condition factor of A. surinamensis.

The Fishmeal Revolution: The Industrialization of the Humboldt Current by Kristin A. Wintersteen

Reviewed by: The Fishmeal Revolution: The Industrialization of the Humboldt Current by Kristin A. Wintersteen Kellen Backer (bio) The Fishmeal Revolution: The Industrialization of the Humboldt Current By Kristin A. Wintersteen. Berkeley: University of California Press, 2021. Pp. 246. Kristin Wintersteen's The Fishmeal Revolution tells a transnational story linking the fish of the Humboldt Current to the global food supply. Situated in the Pacific, off the western coast of South America, the Humboldt Current's constant churn of nutrients sustains fish that served as fodder for industrialized meat production in the second half of the twentieth century. Wintersteen's monograph gives both a very broad overview, looking into the longer history of the current from "deep time" to the present, as well as a narrower history of fishing boom towns in Chile and Peru. The story is both local, national, and international, as Wintersteen follows science, capital, regulations, and fishmeal across the world. The Humboldt Current supports a plethora of fish, particularly anchovetas and sardines, small fish that can be made into fishmeal and fish oil. At times, the current supports enormous schools of fish, something naturalists and the people living in the region have long noticed, though climactic events like El Niño dramatically shape fish availability. While many aquatic creatures thrive in the current, the smaller species of fish, which were less desirable as food, became useful in creating products that provided nutrients for the industrialized production of chickens, hogs, and even farmed fish. And yet, few consumers know of the linkages between the ocean and their dinner. After providing a long history of the Humboldt Current and a background to the industrial uses of fish products from 1840–1930, Wintersteen looks closer at the history of the region's fishing industries. Starting in the 1950s, the fishmeal industry exploded in Chile and Peru, and fish from the Humboldt Current likely supplied over half of the world's fish-meal from 1950–2010 (p. 5). Wintersteen follows the rise of fishmeal and fish oil production in Chile and Peru, focusing on how local and global science, capital, regulations, and cultures shaped the nascent fishing and fish processing industries. The differing histories of fishmeal production in Peru and Chile offer a compelling story of the impact of state regulations, technology, and the environment. The Peruvian industry focused on fishing for anchoveta, particularly in the boom town of Chimbote, while Chile's fishing industry utilized several species of fish. The transnational comparison between Peru and Chile is highly useful [End Page 589] for understanding the rise of local industry, the role of national governments in shaping fishing industries, and how various places responded to ecological crises. In many ways, Wintersteen's story bears a remarkable resemblance to histories of mining, with its boom and bust towns. The fish-meal trade, however, dependent on fish, faced very different challenges in predicting outputs and managing resources, particularly in a region where events like El Niño altered ecosystems. The dramatic changes in oceanic life and differing responses in Chile and Peru, also under various governments, offer lessons for dealing with environmental crises. To tell this story, Wintersteen draws on an impressive array of evidence from archives in eight countries, including corporate, government, and scientific sources that paint a multi-level, transnational picture of fishing, regulations, and industry. Wintersteen argues that the story of the region is "translocal," and by utilizing such diverse sources, the monograph highlights many interconnections between different places. With such a broad focus, many topics are left out, including a close analysis of fish processing and the uses of fishmeal in industrialized food production. Technology's role in the story is mentioned briefly, such as in the histories of nylon nets or the use of steam to create fishmeal. While the focus on multiple sites helps to make the story translocal, many parts of the history are therefore very short. The Fishmeal Revolution will appeal to many scholars, particularly those interested in envirotechnical history and transnational history. Scholars interested in scientific uncertainty, particularly around the environment, will learn much from this volume. By telling a story that includes businesses, fishers, scientific researchers, and government officials across the globe...

폐어구 발생 저감을 위한 어업규제 개선방안에 관한 연구 - 통발어업 및 문어단지어업 중심으로 -

Until recently, illegal fishing in the coastal fishing industry in Korea has been occurring in many different ways in most industries. Among the types of illegal fishing, it is said that the problem of political and trap fishing, octopus jar fishing, and gill net fishing, which are for fishery regulation measures under the fisheries related laws and regulations, is causingwaste fishing gear. In particular, most of these fisheries, trap fishing and octopus jar fishing, are illegal fishing that violates the rules of operation, and many occurrence wast fishing gear are generated during fishing, whether intentionally or fruitfully. Therefore, it destroys the fragile marine ecosystem environment and causes ghost fishing. And it is leading to the decrease of fishery resources, and many problems are raised in terms of protection and management of fishery resources, and the damage is enormous. In other words, about 380 billion won of fishery damage, which is 10% of the annual catch, is occurring due to the waste fish. In addition, when waste fishes made of styrofoam, plastic, and nylon nets for wast fishing gear are left in the sea for a long time, microplastics are generated, and when marine organisms ingest them and eventually come to our table, human beings finally ingest substances that are very harmful to the human body. For this reason, advanced countries including the World Food and Agriculture Organization and the United Nations Environment Program are seeking active management measures to reduce the occurrence of waste fishing gear, which is caused by marine ecosystem environmental pollution and ghost fishing due to the occurrence of waste fish. This study sought ways to reduce the occurrence of waste fishing gear by eradicating violations of fishing regulations on trap fishing and octopus jar fishery which are reducing fishery resources by marine ecosystem contamination and ghost fishing by illegal fishing Therefore, the present laws and regulations related to fishery regulation are reviewed and the problems are considered to suggest legal improvement measures to reduce the occurrence of waste fishing gear

Nylon nets: a simple pest exclusion barrier technique to manage rhinoceros beetle menace in coconut plantations

Oryctes rhinoceros (L.) is a major pest of palms worldwide. Seedlings and juvenile palms are more vulnerable to beetle damage and in severe cases, inflicting palm death. The present study was to develop a physical pest control technique for juvenile palms using nylon nets as a pest exclusion barrier. The unopened spear leaf with –two to four adjacent leaf bases were loosely wrapped with the nylon nets of different mesh size during June - December 2017 (N = 40). Results revealed that the damaged leaves were reduced from 61.02 to 7.53% (t = 17.23; p < 0.001). Further experiment was up scaled in 120 palms during June – December 2018 and the beetles trapped in nylon nets were recorded at weekly intervals. Nylon nets entrapped 618 adult beetles that comprised 61.80% females and 38.18% males with corresponding sex ratio of 1.61: 1. Thus, use of nylon nets as a pest exclusion barrier guarded the young palms from beetle attack and additionally acted as passive trap by entrapping 20.6 beetles/week/120 palms without any insecticidal intervention.

Comparing the efficiency of monofilament and regular nets for capturing bats.

Regular nylon or polyester mist nets used for capturing bats have several drawbacks, particularly that they are inefficient at sampling insectivorous species. One possible alternative is to use monofilament nets, whose netting is made of single strands of yarn instead of several as regular nets, making them less detectable. To date, only one study has quantified the differences in capture rates between monofilament and regular mist nets for the study of bats, yet surprisingly, its findings suggest that the latter are more efficient than the former. Here, we provide further evidence of the differences in sampling efficiency between these two nets. We captured 90 individuals and 14 species in regular nets and 125 individuals and 20 species in monofilament nets. The use of monofilament nets increased overall capture rates, particularly for insectivorous species. Species accumulation curves indicate that samples based on regular nets are significantly underestimating species diversity, most notably as these nets fail at sampling rare species. We show that incorporating monofilament nets into bat studies offers an opportunity to expand records of different guilds and rare bat species and to improve our understanding of poorly known bat assemblages while using a popular, relatively cheap and portable sampling method.

Bio-efficacy and wash-fastness of a lambda-cyhalothrin long-lasting insecticide treatment kit (ICON\xae Maxx) against mosquitoes on various polymer materials

BackgroundLong-lasting efficacy of insecticide-treated nets is a balance between adhesion, retention and migration of insecticide to the surface of netting fibres. ICON® Maxx is a twin-sachet ‘home-treatment kit’ of pyrethroid plus binding agent, recommended by the World Health Organization (WHO) for long-lasting, wash-fast treatment of polyester nets. While knitted polyester netting is widely used, fine woven polyethylene netting is increasingly available and nets made of cotton and nylon are common in Africa and Asia. It is important to investigate whether ICON Maxx is able to fulfill the WHO criteria of long-lasting treatment on a range of domestic fabrics to widen the scope for malaria protection.MethodsThis study was a controlled comparison of the bio-efficacy and wash-fastness of lambda-cyhalothrin CS, with or without binder, on nets made of cotton, polyethylene, nylon, dyed and undyed polyester. Evaluation compared an array of bioassays: WHO cone and cylinder, median time to knockdown and WHO tunnel tests using Anopheles mosquitoes. Chemical assay revealed further insight.ResultsICON Maxx treated polyethylene and polyester netting met the WHO cone and tunnel test bio-efficacy criteria for LLIN after 20 standardized washes. Although nylon and cotton netting failed to meet the WHO cone and cylinder criteria, both materials passed the WHO tunnel test criterion of 80% mortality after 20 washes. All materials treated with standard lambda-cyhalothrin CS without binder failed to meet any of the WHO bio-efficacy criteria within 5 washes.ConclusionThe bio-efficacy of ICON Maxx against mosquitoes on netting washed up to 20 times demonstrated wash durability on a range of synthetic polymer and natural fibres: polyester, polyethylene, nylon and cotton. This raises the prospect of making insecticide-binder kits into an effective approach for turning untreated nets, curtains, military clothing, blankets—and tents and tarpaulins as used in disasters and humanitarian emergencies—into effective malaria prevention products. It may provide a solution to the problem of reduced LLIN coverage between campaigns by converting commercially sourced untreated nets into LLINs through community or home treatment. It may also open the door to binding of non-pyrethroid insecticides to nets and textiles for control of pyrethroid resistant vectors.