We propose an airborne ultrasound non-destructive testing method to visualize multiple defects in thin metal plates. Conventional amplitude-based imaging struggles to detect multiple defects due to signal attenuation caused by scattering at preceding defects. To address this, we investigated phase imaging and compared it with a method applying amplitude attenuation compensation to conventional imaging. Verification was conducted through finite element method analysis and experiments using a duralumin plate with three series-aligned wall-thinning defects. While conventional amplitude imaging identified only the defect closest to the excitation point, both investigated approaches successfully visualized all three defects, confirming the effectiveness of phase imaging. Furthermore, assuming practical field applications, phase imaging was evaluated at various incident angles (0 degrees, 45 degrees, and 90 degrees) relative to the defect alignment. Results demonstrated successful imaging across all angles, proving its robustness.
. The simplification of agricultural landscapes is a major factor in eroding the relational values connecting communities and their environments. Integrated landscape approaches help address these issues but struggle to balance conservation and production in agricultural systems. Globally Important Agricultural Heritage Sites (GIAHS) focus on preserving agricultural heritage in areas where traditional farming practices have maintained high agrobiodiversity and ensured food and livelihood security. These sites share features such as mosaic landscapes, community-based use of resources, and cultural traditions related to seasonal farming events, yet little is known about what sustains them today. This study aims to identify and classify key attributes of heritage farming systems to better understand their functioning as integrated landscape approaches. Using a Q-survey based on 34 statements and three open questions, we examined key features of heritage agricultural systems, the impacts of the GIAHS designation, and the challenges faced by local farming systems. We collected 31 responses from GIAHS community members, including experts and researchers, and identified four categories of GIAHS. Category 1 focused on product certification, category 2 was centered on producing staple foods with short marketing channels, and category 3 focused on exports. Category 4 was centered on traditions, cultural values, and reducing the impacts of climate change. Respondents shared that the designation was especially beneficial for creating awareness and stimulating policies for heritage and ecosystem preservation. It was also reported that land abandonment, the aging population, and climate change are common challenges faced by heritage farming systems. This study suggests that GIAHS share several elements with integrated landscape approaches, such as their focus on dynamic conservation, multifunctional land uses, and multi-level stakeholder engagement and their unique focus on heritage preservation may help to bridge conservation and production goals in agricultural systems.
Silicon (Si) is a promising anode material for lithium-ion batteries due to its high lithium storage capacity; however, severe volume expansion during charge-discharge cycling causes electrode degradation and rapid capacity fading. While binders are essential for maintaining electrode integrity, high-performance binders are often costly, complex to process, and dependent on organic solvents. Aqueous binders derived from natural polymers therefore represent attractive alternatives in terms of cost, sustainability, and environmental compatibility. Although chemically modified lignin binders are promising for Si electrodes, previous studies have only suggested the existence of two distinct thermal treatment approaches-low- and high-temperature processing-and no study has systematically compared these two methods. Herein, we report a modified kenaf-derived lignin copolymerized with polyacrylamide (KL-PAM) as an aqueous binder for Si electrodes and systematically investigate the effect of thermal treatment temperature on its stabilization mechanisms. Low-temperature-treated KL-PAM electrodes at 200 degrees C accommodated Si volume expansion through binder flexibility and adhesion, whereas high-temperature-treated electrodes were stabilized by carbonization-induced hardening of KL-PAM, which also enhanced electronic conductivity. As a result, high-temperature-treated electrodes at 600 degrees C exhibited superior rate capability, while capacity retention was comparable between the two regimes. Intermediate-temperature treatment was ineffective, leading to binder failure. This study clarifies thermally controlled dual stabilization mechanisms of lignin-based binders and provides guidance for the development of sustainable binders for Si electrodes in lithium-ion batteries.
Nurse plants can modify local microenvironments and influence the performance of co-occurring species in alpine ecosystems. While facilitative interactions between cushion plants and their beneficiaries have been widely studied, little is known about how alpine shrubs influence the balance between facilitation and competition across heterogeneous microhabitats. Such knowledge is increasingly important because shrub expansion is occurring in many alpine regions under climate warming. We examined how microhabitats formed by the creeping pine Pinus pumila affect the growth, leaf traits, and foliar chemistry of the dwarf shrub Vaccinium vitis-idaea on Mt. Norikura, Japan. We compared dense shrub thickets on slopes (MAT), isolated patchy shrubs on ridges (PATs), and open bare ridges without pine cover (OUTs). We quantified environmental conditions (light availability, wind velocity, soil moisture, and nutrient availability), leaf morphology (leaf mass per area; LMA), foliar chemistry (C, N, and P contents, δ13C, δ15N), and growth traits (shoot length and plant height) of V. vitis-idaea. MAT and PATs showed lower canopy openness and wind exposure than OUTs, while soil conditions were more strongly influenced by topography than by shrub presence. V. vitis-idaea exhibited greater shoot length, plant height, and foliar N under MAT, but higher LMA and δ13C in OUTs, indicating acclimation to high-irradiance and drier conditions. These results suggest that P. pumila simultaneously mitigates wind exposure and dry conditions while imposing light limitation, resulting in trait-specific responses of V. vitis-idaea. Growth traits reflected competitive responses to shading, whereas foliar δ13C indicated facilitative effects associated with improved water availability. Our findings highlight the ecological importance of non-cushion nurse plants in alpine ecosystems.
We present design guidelines for a sub-terahertz (THz) sensor based on a semiconductor microcavity probed by transmission using 1.5 mu m light. A 3 lambda cavity made of an InAs/GaAs quantum dot superlattice (QDSL) structure sandwiched between two GaAs/AlAs distributed Bragg reflectors is considered, and we predict a THz detection limit of similar to 10 kV/m for a cavity quality factor of similar to 1000 and an electro-optic coefficient of the cavity layer that is 20 times larger than that of GaAs. We show that such a sensor can provide relatively large phase-shift signals even when the QDSL structure does not extend over the entire cavity region; it is sufficient to form a relatively thin QDSL region at each antinode of the optical electric field inside the cavity.
