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Numerous studies have demonstrated that plant species diversity enhances ecosystem functioning in terrestrial ecosystems, including diversity effects on insects (herbivores, predators and parasitoids) and plants. However, the effects of increased plant diversity across trophic levels in different ecosystems and biomes have not yet been explored on a global scale. Through a global meta-analysis of 2,914 observations from 351 studies, we found that increased plant species richness reduced herbivore abundance and damage but increased predator and parasitoid abundance, predation, parasitism and overall plant performance. Moreover, increased predator/parasitoid performance was correlated with reduced herbivore abundance and enhanced plant performance. We conclude that increasing plant species diversity promotes beneficial trophic interactions between insects and plants, ultimately contributing to increased ecosystem services.

It has been reported that the susceptibility of insect herbivores to entomoviruses is affected by phytochemicals ingested during the acquisition of viral inoculum on the foliage of host plants. However, the relationship between this susceptibility and phytochemicals is poorly understood. To test this hypothesis of plant‐mediated effects on this susceptibility, we measured the effects of foliage from three plants, soybeans (Glycine max), collards (Brassica oleracea) and water convolvuluses (Ipomoea aquatica), on the susceptibility of larval beet armyworm (Spodoptera exigua) to nucleopolyhedrovirus (NPV), and analysed six foliar chemicals (total phenolics, peroxidase [POD], catalase [CAT], superoxide dismutase [SOD], endochitinase and exochitinase) in the three plants, respectively. The results of exponential modelling indicated that the LD₅₀ₛ (median lethal dose) of NPV to larvae increased with the increase in both phenolics and POD but declined with the increase in four other foliar chemicals, while the opposite trend was found between median lethal time (LT₅₀) of NPV and the six foliar chemicals. This study reveals that phenolics and POD decrease host susceptibility to the entomoviruses and that CAT, SOD, endochitinase and exochitinase increase this susceptibility.

Three dimensions (natural, social and economic factors) in tradeoff analysis have not been focused in ecology. It is necessary to consider the multi-dimensions through a tradeoff analysis of disturbances to find their positive and negative effects (referred to as two-sidedness). We proposed an 11-step approach to integrate the concepts, methods and examples to understand ecological two-sidedness. We recommend that: (1) ecological complexity and large-scale systematic perspectives need to be integrated; (2) disparate disciplines should be integrated to classify the two-sidedness indicators; (3) models should be adopted to define the characteristic metrics of disturbed ecosystems; (4) researchers need to reconsider evaluation standards and for each indicator with marginal changes; and (5) initial decision-making should refer to the two-sidedness value and that final decision-making should be subject to debate. This approach has great significance for ecosystem management because decision-makers can obtain the superiority and inferiority of disturbance strategies and select optimal strategy.

Green technology a technology to mitigate the effects of human activity on the environment and power efficiency. The scope of this project is only for office or classroom application. The issue of the system in the classroom is the high consumption of energy due to the nonstop operation of the system even though there is no one in the classroom. The main objective of this project is to design. The main objective of this project is to design an autonomous lighting system that can minimize the electricity usage and improve its productivity on human life. The methodology of the system is by using sensors to detect the presence of human and control the intensity of the lamp. Three sensors which are the Infrared (IR), the passive infrared sensor (PIR) and light sensor work separately, but it operates simultaneously under a few conditions. This system can measure and analyze the brightness of light according to the surrounding exposure. The system is designed for easy installation. The outcome of the system is showing the potential application in real time.

Previous studies have shown that the infectivity of baculovirus to herbivores is affected by phytochemicals ingested during the acquisition of viral inoculum on the foliage of host plants. Here, we measured the effects of 14 host plant species on the infectivity of Spodoptera exigua nucleopolyhedrovirus (SeNPV) to its larvae. The order of the LD50 values of SeNPV among the host plants was Ipomoea aquatica > Brassica oleracea > Raphanus sativus > Amaranthus tricolor > Spinacia oleracea > Vigna unguiculata > Solanum melongena > Capsicum annuum > Apium graveolens > Allium fistulosum > Lactuca sativa > Brassica chinensis > Zea mays > Glycine max, with 940.1 ± 2.26, 424.0 ± 0.60, 295.2 ± 1.13, 147.3 ± 0.63, 138.6 ± 0.22, 119.9 ± 0.07, 119.8 ± 0.02, 109.2 ± 0.18, 104.8 ± 0.62, 102.1 ± 0.66, 97.9 ± 0.22, 89.9 ± 0.32, 79.0 ± 0.13 and 64.0 ± 0.38 OBs per larva, respectively, and the values of mean time to death of virus-infected larvae were 6.21 ± 0.11, 7.12 ± 0.10, 7.33 ± 0.21, 6.97 ± 0.02, 7.06 ± 0.01, 7.29 ± 0.03, 7.32 ± 0.05, 7.07 ± 0.08, 7.24 ± 0.11, 7.09 ± 0.13, 7.50 ± 0.06, 7.23 ± 0.01, 7.30 ± 0.02 and 7.19 ± 0.07 days, respectively. The mean time to death of larvae decreased with increasing viral dose, and corrected mortality decreased as the larval mean time to death increased. These findings have significance for understanding the effects of host plants on the infectivity of baculovirus to noctuids.

This study examined the physiological effects of joint and separate parasitism and infection by the endoparasitoid Microplitis pallidipes Szepligeti and the nucleopolyhedrovirus (NPV), respectively, on haemolymph 20-hydroxyecdysone (20-E) titre in Spodoptera exigua (Hubner) larvae. The results indicated that in parasitized larvae, virus-infected larvae (5.7 × 103 and 5.7 × 105 OB/ml) and parasitized larvae infected with virus at 5.7 × 105 OB/ml, compared to healthy larvae, the 20-E all declined during the first 3 days but began to increase from day 4 after treatment, while in jointly parasitized and infected larvae (5.7 × 103 OB/ml), the 20-E declined during the first 4 days but began to increase on day 5 after treatment. Meanwhile, compared to parasitized larvae, the 20-E declined during the first 4 days but significantly increased on day 5 in jointly parasitized and infected larvae (5.7 × 103 OB/ml), while significantly increased during the first 2 days but began to decrease from day 3 after treatment in jointly parasitized and infected larvae (5.7 × 105 OB/ml). Finally, in larvae that were both parasitized and virus infected (5.7 × 103 OB/ml), compared to just virus-infected larvae (5.7 × 103 OB/ml), the 20-E was lower on days 3 and 4 but higher on other days after treatment; in larvae that were both parasitized and virus infected (5.7 × 105 OB/ml), compared to just virus-infected larvae (5.7 × 105 OB/ml), the 20-E was significantly higher at the first 2 days but lower from day 3 after treatment. Our results revealed that 2nd instar larval M. pallidipes in host bodies may release 20-E into the haemolymph of S. exigua larvae and that NPV infection may stimulate S. exigua to release more 20-E during its third to fourth instar larval moulting. We found that this stimulatory effect was greater with higher virus concentrations.

In this study, the effect of acetic acid used as catalyst in promoting the decomposition rate of blowing agent (sodium bicarbonate) in epoxy foam was done. Hard epoxy foam was produced using mechanical mixing technique. Epoxy foam has been tested with adding acetic acid at 5 phr and different content of sodium bicarbonate which are 0, 5, 10, 15, and 20 phr, respectively. The effect of acetic acid on the viscosity, density, mechanical properties, and dielectric constant has been studied. The results were compared between with and without acetic acid in the system. Viscosity reading was increased with increasing the content of sodium bicarbonate due to the rapid production of bubbles that created porosity in the structure of epoxy foam. The addition of acetic acid is able to reduce the dielectric constant. In overall, the density, flexural strength and modulus dropped for the epoxy foam with acetic acid as compared to that of without acetic acid.