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Recently desertification of Alpine-cold semi-humid grassland has become increasingly serious on the eastern edge of the Qinghai-Tibet plateau. However, the restoration and control of desertified land in these areas have not received enough attention as in arid and semi-arid areas, and little is known about the vegetation community and soil microbiological properties during the ecological restoration in Alpine-cold semi-humid desertified areas. In this paper, the method of fencing, removing grazing and planting Tamarix ramosissima was taken as the measure for ecological restoration of Alpine-cold desertified land in Northwest Sichuan. The results showed ecological restoration resulted in significant improvement in the height, coverage, density, biomass, and diversity of vegetation communities, numbers of soil microorganisms (including bacteria, actinomycetes and fungi). Microbial biomass carbon and nitrogen, and urease, invertase and protease activities increased after the restoration, especially in the 0–20 cm layer. These trends increased with increasing restoration age but decreased with increasing soil depth. Ecological restoration by fencing, non-grazing and planting T. ramosissima is therefore considered an effective and applicable measure to restore vegetation and soil microbiological properties and control desertification in the Northwest Sichuan, and is recommended for adoption in Alpine-cold semi-humid sandy areas on a large scale.

In this work, an out-of-plane connection in an orthogonal assembly is demonstrated. The proposed method for the orthogonal connection will help to overcome critical issues faced in this type of connection, such as lead transfer and bonding plane mismatch. It proposed to utilize the laser assisted soldering technique to achieve the lead transfer in the connection. Being a highly flexible probe array, it is more conformal to the tissue, minimizing tissue damage after implantation. Compared to previous works, the proposed flexible probe array has excellent flexibility and can easily conform to the shape of tissue, preventing the micromotion of probe after implantation. The measured impedance at the typical frequency of action potential (1 kHz) is about 12.8 kΩ.

Traumatic brain injury (TBI) can be worsen by the secondary brain injury which will the major prognostic factor for the patient condition. The major parameters for monitoring the TBI are the intracranial pressure, partial brain oxygen level and the brain temperature. This leads to the development of an integrated intracranial microsystem which effectively monitored the condition of the TBI patient. This paper will present the biocompatible packaging and its in-vitro result for the microsytem.

In this work, an integration method of low profile probe array system is proposed for minimizing the tissue trauma after implantation. The planar neural probes was assembled with a Si platform to form a 3D probe array, which is then connected to the application-specific integrated circuit (ASIC) chip with a flexible polyimide cable by flip-chip bonding to complete the whole integration. The probe array and flexible polyimide cable have undergone electrical tests to prove to be highly stable and reliable. With the specially designed components, flexible assembly is achieved. The proposed integration method achieved a low profile of the probe array and the requirements for its applications. The impedance of the assembled probe electrode in artificial cerebrospinal fluid (aCSF) is measured to be about 1.1 MΩ at 1kHz.

Assembly methods with specially designed Si interposer and Si platform are described for low profile 3D neural probe array assembly in this paper. In this method, in order to assemble the probe array with low profile and connect the probe with ASIC chips, an interposer is designed to connect the electrical pads on the sidewall of the probe and the electrical pads on the surface of the Application-specific integrated circuit (ASIC) chip. To hold the probe array and ASIC chip, a Si platform is designed with through Si slot for insertion of probe and cavity for holding the interposer. The electrical interconnections between the probe and the ASIC chip are formed by conventional flip chip bonding method. Therefore the throughput for the 3D probe array can be improved. Another advantage of the developed assembly method is that the backbone of the probe can be embedded inside the cavity of the Si platform, as a results, the profile of the probe array on top of the Si platform is controlled lower than 1mm easily, which make sure it does not touch skull after implant into the brain.

This paper presented an integration method for biomedical implants by using solder bonding and highly flexible polyimide (PI) cable. The proposed integration method can overcame the problems in flexible cable assembly before. It can achieve a small form, and better reliability, and is easier for fragile MEMS device bonding by using solder bonding. Therefore, it is suitable for various MEMS devices integration. The effect of the metal materials and reliability of the flexible cable with thin metal trace were studied. SEM and TEM/EDX analysis were performed to evaluate the boning interface microstructures. Electrical tests were carried out to study the resistance of the interconnects. Thermal cycling test with temperature range of −40/+125ଌ with 15mins dwell for 500 cycles was used to evaluate the reliability properties of the interconnects. The results showed good bonding interface, low electrical resistance and there were no major changes in resistance during thermal cycling. Hence, it implied that the interconnections were highly stable and reliable by using the proposed bonding method.