Wetland ecosystems act as natural freshwater purification systems, but their rich biodiversity is being threatened with the introduction of the non-native freshwater snail, Pomacea canaliculata. This ...study was conducted to measure the herbivory effects and growth rate of P. canaliculata on common macrophytes: Ipomoea aquatica, Ipomoea batatas, Pandanus amaryllifolius and Cucurma longa. In separate experiments, the macrophyte species were served as the snails’ food as individual species and simultaneously. In the individual treatment, the growth pattern and rate were based on the snails’ weight (mg/snail/day; n = 9) while the individual feeding consumption (mg/snail/day) was calculated from the leftover food. In the simultaneous treatment, the herbivory effects were evaluated as the feeding preference (%) from observations every two hours, while the total feeding consumption (mg) was calculated based on the food remaining after a 12-hour experiment (3 replicates: total n = 27). The results indicated that the growth pattern was significant for snails grazing on I. aquatica but not when other macrophyte species were eaten. The individual feeding consumption was higher when using I. aquatica than P. amaryllifolius but the growth rate for snails grazing on I. aquatica and P. amaryllifolius did not differ significantly. Meanwhile, the consumption of C. longa deterred the snails’ growth rate. Although the snails consumed all the macrophytes in the individual experiment, when given the species simultaneously, the feeding preference and total feeding consumption were directed significantly more toward I. aquatica than P. amaryfollius and C. longa. We conclude that P. canaliculata is a generalist feeder given a limited choice of food but tends to show a strong feeding preference after being introduced to more food choices. These findings indicate that the introduction of P. canaliculata into wetland ecosystems may increase the herbivory effects on macrophytes, making these ecosystems vulnerable to the impact of eutrophication and biodiversity reduction.
This study investigates the effect of Pleurotus spent mushroom compost as green supplementary nutrient in tissue culture. Different concentration of Pleurotus spent mushroom compost in powder (SMC) ...and activated carbon (SMCAC) were added into Murashige and Skoog media (MS) with 0.1 mg/L 6-benzylaminopurine (BAP). The shoot regeneration of Clinacantus nutans plant such as number of shoots, number of leaves and length of leaves were recorded for four weeks. Collected data was analyzed using one way analysis of variance (ANOVA) and Tukey test through the SPSS Statistics 21 software. The 0.1 g/L SMC recorded the highest leaves numbers. Meanwhile, 0.2 g/L SMC showed highest performance in length of shoot. The SMCAC showed a negative response in number of leaves and shoot as well as length of shoot. In summary, the SMC showed significant performance in number of leave and shoot length but less effective on number of shoot. In contradictory, the SMCAC reported poor performance in shoot regeneration but contribute in absorption of nutrient from environment and storage of the nutrient asfunction of biochar. Therefore, the SMC has a high potential as a green supplementary nutrient for tissue culture. The application of this material has contributes into the green technology via convert waste to product, which is in-line with zero waste concept.
Dragon fruit (Hylocereus polyrhizus) is a tropical fruit. Recently, it has gained interest from the public due to its potential beneficial effects on health. The acclimatization of micropropagated ...Hylocereus polyrhizus depends on the application of gibberellic acid (GA3) to increase plant growth. Eggshells are waste materials from industrial sectors, and they are composed of calcium source that is vital for the development of plant shoots and root. The objective of this research is to investigate the effect of different concentrations of GA3 and eggshell either added individually or in combination on the growth of shoot length and shoot diameter of H. polyrhizus. The result showed the shoot length of the H. polyrhizus increased by approximately 54.69%, from 0.64 ± 0.13 cm to 0.99 ± 0.26 cm, as the concentration of GA3 increased from 0 ppm to 10 ppm. Furthermore, this finding also reported that with eggshells, GA3 showed an adverse effect on the development of shoot diameter. The growth of shoot length and shoot diameter with the addition of eggshell was different, perhaps due to the gibberellic acid affecting the shoot length but not the shoot diameter. Generally, the growth of shoot length and shoot diameter with eggshells was higher in comparison with those without eggshells. With that, we can prove that eggshell is a good additive to promote the growth of H. polyrhizus.
Wetland ecosystems act as natural freshwater purification systems, but their rich biodiversity is being threatened with the introduction of the non-native freshwater snail, Pomacea canaliculata. This ...study was conducted to measure the herbivory effects and growth rate of P. canaliculata on common macrophytes: Ipomoea aquatica, Ipomoea batatas, Pandanus amaryllifolius and Cucurma longa. In separate experiments, the macrophyte species were served as the snails' food as individual species and simultaneously. In the individual treatment, the growth pattern and rate were based on the snails' weight (mg/snail/day; n = 9) while the individual feeding consumption (mg/snail/day) was calculated from the leftover food. In the simultaneous treatment, the herbivory effects were evaluated as the feeding preference (%) from observations every two hours, while the total feeding consumption (mg) was calculated based on the food remaining after a 12-hour experiment (3 replicates: total n = 27). The results indicated that the growth pattern was significant for snails grazing on I. aquatica but not when other macrophyte species were eaten. The individual feeding consumption was higher when using I. aquatica than P. amaryllifolius but the growth rate for snails grazing on I. aquatica and P. amaryllifolius did not differ significantly. Meanwhile, the consumption of C. longa deterred the snails' growth rate. Although the snails consumed all the macrophytes in the individual experiment, when given the species simultaneously, the feeding preference and total feeding consumption were directed significantly more toward I. aquatica than P. amaryfollius and C. longa. We conclude that P. canaliculata is a generalist feeder given a limited choice of food but tends to show a strong feeding preference after being introduced to more food choices. These findings indicate that the introduction of P. canaliculata into wetland ecosystems may increase the herbivory effects on macrophytes, making these ecosystems vulnerable to the impact of eutrophication and biodiversity reduction.
The excellent properties of graphene, such as its high thermal conductivity, high electrical conductivity, and high electron density, make it an ideal candidate as a detector material in high-energy ...physics applications. In this work, we demonstrate the feasibility of multi-layer graphene (MLG) as a detector material in a high-energy environment. The Geant4 software package was used to estimate the energy of the deposited electrons within various thicknesses of MLG, ranging from 3 to 20 nm. The efficiency of the MLG as a detector material was further analyzed from the scattering angle and the yield of the secondary particles produced from the electron interaction with the material. The incident electron’s kinetic energy used herein ranged between 30 keV and 1 GeV, at a particle fluence of 1×107 e/cm2. The results show that the deposited energy was relatively low for the interaction with 1 MeV electrons, and dramatically increased as the thickness increases beyond 15 nm. This result was further supported by the highest yield of gamma radiation recorded by the interaction with a kinetic energy larger than 1 MeV, for thickness larger than 15 nm. The results suggest that the MLG works best as a charged particle detector in low energy ranges, while for high energy ranges, a thickness over 15 nm is suggested. The findings demonstrate that a MLG with a thickness larger than 15 nm could potentially be used as a detector material in high-energy conditions.
This work demonstrated the effects of 1.2 GeV high-energy electron beam irradiation on a few-layers of graphene (FLG) and multi-layer graphene (MLG) films grown via an in-house hot wire chemical ...vapour deposition (HWCVD) system. The FLG and MLG films were grown on highly doped n-type c-Si (100) substrates which were pre-treated using argon plasma (50 W) for 1 min and 10 min, respectively. The as-prepared samples were then irradiated using a 1.2 GeV high-energy electron beam with a dosage of 1.2 × 109 e-/cm2 at atmospheric and room temperature ambient conditions. The effects of the irradiation-mediated defects on the carbon lattice structure of both graphene samples were validated from the decreased sp2 C=C carbon content, and the increase in the adventitious carbon contamination C-O-C content. Raman results showed an elevation of the ID/IG ratio and blue-shift of the 2D and G band peaks for both the irradiated samples, which validated the mediated defects due to the dislocation of carbon atoms in the graphene sheets. The blue-shifted of 2D and G peaks were much more significant in the MLG than FLG which may indicate a better self-reconstructing property for the MLG atomic network, compared to the FLG. The stability of the films against high-energy electron beam irradiation was validated by their conductivity and surface topography. In conclusion, HWCVD grown graphene nanoplatelet films have high potential for graphene-based high-energy charged particle detectors.
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