Chiang Mai Journal of Science

     Fusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (FOC), is a destructive disease that targets the vascular system of banana plants, resulting in wilting and eventual death. FOC can be divided into four physiological races 1, 2, 3, and 4 according to their ability to cause disease, the range of hosts infected, and their genetic traits. FOC Races 1 and 4 have been detected in Southeast Asia. This study used proteomic analysis to identify the stress response proteins involved in the interaction between banana plants and FOC Race 1. These proteins were compared with those previously reported in Race 4 to explore the similarities and differences in plant basal defense response mechanisms against FOC. A total of 758 proteins were identified including 401 in bananas infected with FOC Race 1 and 357 in the control group. Among these, 238 were unique to the control group, while 281 were specific to the FOC Race 1-infected samples. Key stress response-related proteins including β-1,3-glucanase, lipoxygenase, chiti nase, and leucine-rich repeat (LRR) disease resistance proteins exhibited expression patterns consistent with previously reported data. Notable differences were observed in the expression of heat shock proteins (HSPs), especially Hsp70, Hsp90, and stress-response A/B barrel domain-containing proteins. These proteins were predicted to functi on synergisti cally in response to FOC Race 1 infection but acted independently of the jasmonic acid signaling pathway. Our findings suggest that HSPs show potential as an alternative defense mechanism for developing strategies to manage FOC Race 1.

    Plant resistance to herbivores is a key component of integrated pest management (IPM). Silicon (Si) amendment in rice (Oryza sativa) influences multiple plant defense responses, particularly against phloemfeeding insects like the rusty plum aphid (Hysteroneura setariae). This greenhouse study examined the effects of Si supplementation (calcium silicate, Ca₂SiO₄) at 0%, 2%, and 4% per gram of soil on silicification and aphid infestation. Defense-related enzyme activities—including peroxidase (POD), polyphenol oxidase (PPO), and phenylalanine ammonia-lyase (PAL)—were measured in aphid-infested rice plants with and without Si amendment. Results showed that Si-treated plants exhibited increased silicification and larger silicon cell size in leaf sheaths than untreated plants. Aphid infestation was significantly lower in plants amended with 2% and 4% Si than in non-amended controls. Additionally, POD, PPO, and PAL activities were higher in Si-treated plants than in non-amended aphid-infested plants. These findings suggest that Si supplementation enhances rice resistance to aphids by inducing plant defense responses, offering a promising strategy for sustainable rice IPM.

     Plastic waste management in Thailand remains a major challenge, largely due to household waste. Most plasti c waste is currently managed through landfi lling. Implementi ng energy recovery methods by pyrolysis is crucial to miti gate this problem. This study investi gated the properti es and performance of pyrolysis oil from landfi lled plasti c waste and blended with diesel in diff erent rati os for applying diesel engine generators. The chemical analysis by FTIR technique showed that the pyrolysis oil had a compositi on close to that of diesel, with suitable C-H and C=C functi onal groups for combusti on. The results revealed that the blended oil’s fl ash and igniti on points increased with the proporti on of pyrolysis oil. The pyrolysis oil and diesel blending rati o of 40: 60 obtained the highest fl ash point at 88.67°C and igniti on point at 91.33°C, indicati ng enhanced combusti on effi ciency. Meanwhile, the 30:70 blending rati o demonstrated the opti mal specifi c fuel consumpti on (BSFC) and achieved the highest engine effi ciency at 84.94%. Regarding exhaust emissions, all blending rati os resulted in a slight increase in nitrogen oxide (NOx) emissions,while sulfur dioxide (SO₂) was not detected in any blend. Pyrolysis oil shows promising performance as an alternati ve fuel, parti cularly when uti lized in opti mal blend rati os, as it not only reduces the environmental burden of plasti c waste but also contributes to the preservati on of fossil fuel resources for future industrial applicati ons.

     This study aims to investigate the utilization of lightweight expanded clay aggregate (LECA) produced by combining clay with industrial waste as a planting material for soil moisture retenti on. Lightweight expanded clay aggregate is a growing media material composed of clay pellets subjected to high temperatures. This substance is created by combining clay with pore-forming elements, such as pulverized waste from the automotive sector. The compressed waste particles comprise polymer fiber, glass shards, lubricating oil, and various other components. This waste is imported from overseas to serve as a cost-effective fuel source for energy production. In order to further develop its potential applications, it is combined with clay to investigate the feasibility of developing a novel substrate to replace materials like perlite and vermiculite that are currently in use. The experiment entails molding a mixture of clay and waste fragments in different proportions and subjecting them to fire at temperatures ranging from 700 to 800 degrees Celsius. The research results indicated that 30% of clay with 70% of industrial waste is the most suitable combination and slip casting parameters. Examining the physical and chemical characteristics of the LECA reveals that they possess pores capable of efficiently retaining water and moisture. The bulk density was 1.05 g/cm³, the apparent porosity was 53.21%, and the water absorpti on was 50.60%, which indicates their high capacity to absorb water. The pH of LECA suited for plant growth commonly lies within the range of 6.5 to 8, which is close to the suitable pH value. The experiment has yielded a novel, highly permeable, lightweight expanded clay aggregate that efficiently retains moisture in the topsoil and is available in many forms. Furthermore, using industrial waste and employing low-forming temperatures enable this innovation to be ecologically sustainable.

     In this paper, a small, simple and compact bidirectional linear piezoelectric stick-slip actuator (PSSA) capable of realizing high-speed drive at low frequencies is proposed. Based on the stick-slip driving principle and the lever-type displacement amplification mechanism using asymmetric inertial driving foot structure to drive the slider to generate motion, the output performance of the piezoelectric actuator is improved. In this work, the structural design and working principle of the actuator are described in detail, and the amplification ratio of the flexible amplification mechanism is calculated and the structural parameters are optimized through theoretical analysis and finite element simulation analysis. Finally, a prototype is fabricated and tested to characterize the output performance in terms of driving voltage, driving frequency, output speed and load capacity. The test results show that the maximum output speed of the actuator is 5.01mm/s, the maximum horizontal load and resolution are 70g and 125nm, respectively, in addition, the actuator has a better bidirectional driving performance, the forward and reverse motion accuracy is 80nm. The comparison of the performance of the actuator with the existing bidirectional actuator reflects the advantages of the proposed actuator in output performance.

     Utilizing the inverse power transformation methodology, we introduce a novel continuous three-parameter probability distribution termed the inverse power generalized Maxwell distribution, which extends upon the existing Maxwell distribution. In this paper, we establish Key functions relevant to survival analysis and elucidate various statistical properties of the model. Our investigation delves into the estimation of model parameters by employing and rigorously evaluating six distinct estimation techniques through extensive numerical simulations. To assess the practical utility of the proposed model, we analyze two real-world engineering datasets. Empirically, the results demonstrate that the proposed model provides a superior goodness-of-fit compared to alternative models considered in this study.