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Advanced sensing technologies such as remote sensing and sensor networks, important for enhancing land use through soil condition monitoring, are facing issues including high machine learning costs, limited measurement point density, and environmental impact. This study introduces a remote sensing method that offers both direct and wide-area sensing of soil properties using a dispersible, biodegradable cuboid-shaped isotropic metamaterial equipped with a water-soluble Mg-based resonance antenna structure. The symmetrical metal patterns ensure isotropic reflectance within the 1.2–3.6-GHz range, enabling robust sensing even when the metamaterial is dispersed randomly on the soil. The degradation of the Mg antenna in the soil presents a significant reflection reduction from 80% to 20% at a 2.4-GHz resonant frequency on the soil, promoting the feasibility of combination with a simple wireless measurement system. Integration with functional coatings that dissolve in response to specific soil substances such as pH-sensitive hydroxyapatite leads to the development of biodegradable soil remote monitoring sensors, offering precise, sustainable land management.

Type 1 diabetes mellitus (T1DM) affects 8.4 million people worldwide, with patients primarily relying on exogenous insulin injections to maintain blood glucose levels. Islet transplantation via the portal vein has allowed for the direct internal release of insulin by glucose-sensitive islets. However, this method might not be desirable for future cell therapy transplanting pluripotent stem cell-derived β cells, facing challenges including difficulties in cell retrieval and graft loss due to the instant blood-mediated inflammatory reaction (IBMIR). Here, we established a subcutaneous transplantation protocol using an atelocollagen sponge as a scaffold. While the subcutaneous site has many advantages, the lack of a vascular bed limits its application. To address this issue, we performed angiogenesis stimulation at the transplantation site using bFGF absorbed in a gelatin sponge (Spongel), significantly improving the microvascular area. Our in vivo experiments also revealed angiogenesis stimulation is crucial for reversing hyperglycemia in streptozotocin (STZ)-induced diabetic mice. In addition to the angiogenic treatment, an atelocollagen sponge is used to carry the islets and helps avoid graft leakage. With 800 mouse islets delivered by the atelocollagen sponge, the STZ-induced diabetic mice showed a reversal of hyperglycemia and normalized glucose intolerance. Their normoglycemia was maintained until the graft was removed. Analysis of the harvested islet grafts exhibited a high vascularization and preserved morphologies, suggesting that using an atelocollagen sponge as a scaffold helps maintain the viability of the islet grafts.

Conventional methods for estimating 1D or 2D velocities were developed for the dynamic measurement of carotid walls. However, a carotid wall moves in 3D due to a heart pulsation, and the wall motion velocity in the longitudinal-axis cross-section is affected by out-of-plane displacements that cannot be measured with a 1D array probe. To estimate the out-of-plane displacement, we proposed the cross-shaped probe. The cross-shaped probe can estimate 3D velocity vector with 256 transmit-receive channels. Single or multiple focused beams were transmitted by the main array of the cross-shaped probe, and the RF signals received all the elements were used for 3D velocity vector estimation based on the multi-angle Doppler method. Numerical simulations and basic experiments showed that out-of-plane displacements in the longitudinal-axis cross section can be estimated. Furthermore, the in vivo experiments on a human common carotid artery showed that arterial wall motion during a cardiac cycle can be measured.

A phase-sensitive 2D motion estimator is useful for measurement of minute tissue motion. However, the effect of conditions for emission of ultrasonic waves on the accuracy of such an estimator has not been investigated thoroughly. In the present study, the accuracy of the phase-sensitive 2D motion estimator was evaluated under a variety of transmission conditions. Although plane wave imaging with a single emission per frame achieved an extremely high temporal resolution of 10417 Hz, the accuracy in estimation of lateral velocities was worse than compound-based method or focused-beam method. By contrast, the accuracy in estimation of axial velocities hardly depended on the transmission conditions. Also, the phase-sensitive 2D motion estimator was combined with the block matching method to estimate displacements larger than the ultrasonic wavelength. Furthermore, the results show that the correlation coefficient in block matching has potential to be used for evaluation of the reliability of the estimated velocity.

In order to study the combined nature of 2D and 3D superfluidity and the vortex state in thin4He films formed in porous glasses superflow properties are studied using effective thermal conductance measurements. Detailed study, though still preliminary, reveals quite different features from 2D superfluidity or that of bulk one. For the film with Tc=670 mK, we observe a change of the superflow properties, below 600 mK and when a critical flow velocity is exceeded. This transition is characterized by appearance of quite a long time constant and is indicative of formation of new vortex state. Films with Tc=1015, 1130, 1276 mK do not have this long time constant over the studied velocity, or dQ/dt range for the temperature above 500 mK

Possiblity to utilize thermal conductivity to study superfluid thin4He films on porous glass has been examined in temperature range T=(0.6–1.1)K. The datailed measurements performed for the film in normal state can be qualitatively described by the ideal gas conductance. In the superfluid state at T≈0.6K a sharp increase of the temperature gradient along the sample at a critical heating power has been observed below Tc. This feature is similar to that at T≈1K, where thermal conductivity technique is supposed to be applicable

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.