Phase Transformations and Mechanical Properties in In-Bi-Sn Alloys as a Result of Low-Temperature Storage.

The In-Bi-Sn low-temperature solder alloys are regarded as potential candidates for cryogenic and space exploration applications. This study investigates the variations in the mechanical properties and microstructures of two different compositions: In15wt%Bi35wt%Sn and In30wt%Bi20wt%Sn, after exposure to a low-temperature environment (-20 °C) for 10 months. An increase in the ultimate tensile strength was observed across all the tested samples and a decrease in elongation to failure was observed in In30wt%Bi20wt%Sn. Changes in the microstructure were identified through scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The impact of this low-temperature environment is described, considering the varying proportions and compositions of the three phases (BiIn2(Sn), γ-InSn4(Bi), and ß-In3Sn(Bi)) present within the alloys and their contribution to the mechanical properties.

Mechanical Properties and Microstructure of Binary In-Sn Alloys for Flexible Low Temperature Electronic Joints.

This research evaluates the mechanical properties of a variety of binary In-Sn alloys as potential candidates for low temperature electronic joints. The tensile and hardness tests of as-cast In-5Sn, In-12.5Sn, In-25Sn, In-30Sn, In-35Sn, In-40Sn, In-50Sn, In-60Sn, In-80Sn (wt.%) were assessed at room temperature and compared to those of pure In and Sn. The ultimate tensile strength (UTS) increased from 4.2 MPa to 37.8 MPa with increasing tin content in the alloys under the testing condition of 18 mm/min and the results showed little difference under a lower strain rate (1.8 mm/min). Most compositions showed good ductility in tensile testing with an average of 40% elongation. A melting point range of 119.3 °C to 194.9 °C for tested alloys was measured using differential scanning calorimetry (DSC). The microstructure investigated by scanning electron microscopy (SEM) was discussed with respect to the mechanical properties and it has been found that the presence of the Sn-rich γ-InSn4 phase in the microstructure has a significant impact on mechanical properties. The fundamental data from this study can be used for the development of new low temperature In-Sn alloys.

Design, synthesis and biological evaluation of novel osthole-based derivatives as potential neuroprotective agents.

A total of 26 compounds based on osthole skeleton were designed, synthesized. Their cytoprotective abilities of antioxidation, anti-inflammation and Aß42(Amyloid ß-protein 42)-induced neurotoxicity were evaluated by MTT assays. Mechanism of the action of selected compounds were investigated by molecular docking. AlogP, logS and blood-brain barrier (BBB) permeability of all these compounds were simulated by admetSAR. Most of the compounds showed better antioxidative and anti-inflammatory activities compared with osthole, especially OST7 and OST17. The compound OST7 showed relative high activity in neuroprotection against H2O2 (45.7 ± 5.5%), oxygen glucose deprivation (64.6 ± 4.8%) and Aß42 (61.4 ± 5.2%) at a low concentration of 10 µM. EC50 of selected compounds were measured in both H2O2 and OGD induced cytotoxicity models. Moreover, NO inhibiting ability of OST17(50.4 ± 7.1%) already surpassed the positive drug indomethacin. The structure activity relationship study indicated that introduction of piperazine group, tetrahydropyrrole group and aromatic amine group might be beneficial for enhancement of osthole neuroprotective properties. Molecular docking explained that the reason OST7 exhibited relatively stronger neuroprotection against Aß because of the greater area of interactions between molecule and target protein. OST7 and OST17 both provided novel methods to investigate osthole as anti-AD drugs.

ANK6, a mitochondrial ankyrin repeat protein, is required for male-female gamete recognition in Arabidopsis thaliana.

Double fertilization in angiosperms involves several successive steps, including guidance and reception of the pollen tube and male-female gamete recognition. Each step entails extensive communication and interaction between two different reproductive cell or tissue types. Extensive research has focused on the pollen tube, namely, its interaction with the stigma and reception by maternal cells. Little is known, however, about the mechanism by which the gametes recognize each other and interact to form a zygote. We report that an ankyrin repeat protein (ANK6) is essential for fertilization, specifically for gamete recognition. ANK6 (At5g61230) was highly expressed in the male and female gametophytes before and during but not after fertilization. Genetic analysis of a T-DNA insertional mutant suggested that loss of function of ANK6 results in embryonic lethality. Moreover, male-female gamete recognition was found to be impaired only when an ank6 male gamete reached an ank6 female gamete, thereby preventing formation of homozygous zygotes. ANK6 was localized to the mitochondria, where it interacted with SIG5, a transcription initiation factor previously found to be essential for fertility. These results show that ANK6 plays a central role in male-female gamete recognition, possibly by regulating mitochondrial gene expression.