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This study investigates the effects of the ubiquitin-proteasome pathway (UPP) on porcine sperm capacitation and its interactions with the cAMP-PKA pathway. The semen of adult Landrace boars was divided into four groups: non-capacitated, capacitated, 10 μM/mL MG132, and 10 μM/mL DMSO groups. We characterized the parameters related to sperm dynamics using a computer-assisted sperm analysis system. The level of sperm protein tyrosine phosphorylation was detected using Western blotting, and the change of zinc ion signal was detected via flow cytometry. The relationship between A-kinase-anchor protein 3 (AKAP3), ubiquitin (Ub), and protein kinase A (PKA) was assessed by co-precipitation assays; to evaluate the interactions between the UPP and cAMP-PKA pathway, threonine, serine, and tyrosine phosphorylation were detected using Western blotting to evaluate the interaction between the UPP and cAMP-PKA pathway; Hoechst staining was used to detect the sperm-egg binding state and evaluate the effects of UPP inhibition. During capacitation, the levels of protein tyrosine, serine, and threonine phosphorylation and ubiquitination of porcine sperm increased, and sperm-egg binding was inhibited (P 0.05). AKAP3 was degraded by UPP, and after inhibiting the 26 S proteasome, ubiquitinated AKAP3 accumulated in large quantities. Our findings indicate that, after the 26 S proteasome was inhibited, PKA was uncoupled from AKAP3 and degraded by UPP; the level of tyrosine phosphorylation induced by PKA-AKAP3 was reduced, the level of serine threonine phosphorylation increased, and the ubiquitination pathway interacted with the phosphorylation pathway and was involved in sperm capacitation.

Thermal mismatch problems can trigger the cracking of the InSb photosensitive layer, the local delamination and the performance degradation of the InSb infrared detector arrays (IDAs). We preferred the balanced composite structure (BCS) proposed by Jeffrey Barton to eliminate these typical failure phenomena. In the BCS, the silicon readout integrated circuit (Si-ROIC) was thinned to make its effective coefficient of thermal expansion (CTE) match the CTE of the InSb photosensitive layer. In order to assess the efficacy of the thinner Si-ROIC in the BCS, with the help of the established InSb IDAs assembly equivalent structure model, we quantitatively analyzed the effectivity of the thinned Si-ROIC in the elimination of the tensile stress (causing the InSb photosensitive layer to crack), the interfacial shear stress (leading to the local delamination of the InSb IDAs), and the peeling stress (giving rise to the edge delamination of the InSb IDAs). We observed that the tensile stress in the InSb photosensitive layer decreases linearly with the thinned Si-ROIC, besides, the interfacial shear stress and the peeling stress also decrease linearly with the thinned Si-ROIC in the range of 300–50 μm. When the Si-ROIC is thinner than 50 μm, the location, in which the local maximal shear stress or the maximal peeling stress appears, moves inward and deviates from its preceding location. All these simulation results clearly confirm that the thinner Si-ROIC in the BCS is an effective approach to concurrently reducing the three main failure stress components in the InSb IDAs assembly, and this major characteristic of concurrently decreasing the three main failure stress components contributes to completely solve the thermal mismatch problems in the InSb IDAs assembly.

Both the local delamination and the local fracture, appearing in the InSb infrared focal plane arrays (IRFPAs) detectors in liquid nitrogen shock tests, restrict the final yield of the InSb IRFPAs detectors. To explore the mechanism of the local delamination appearing in the region of the negative electrode of the InSb IRFPAs detectors, basing on the created structural modeling of the InSb IRFPAs detectors, we obtain the distributions of the interfacial stresses in the different interfaces of the InSb IRFPAs detectors. After comparing the distributions of the simulated interfacial stresses with the measured local delamination region in the InSb IRFPAs detectors, we think that the local delamination originates from the interfacial shear stresses, and the crack extension is the typical sliding mode. Besides, the weakened gluing strength between the InSb chip and the underfill in the negative electrode region also causes this region to be prone to the local delamination. All these findings provide the theoretical references for both the structure design and the structure optimization of the InSb IRFPAs detectors assembly in the future.

An empirical expression for the energy bandgap as a function of alloy composition x and temperature for In1−xAlxSb was reported. The In1−xAlxSb epitaxial layers were grown by molecular beam epitaxy (MBE) on InSb(1 0 0) substrate, utilizing a p+–p+–n–n+ structure. High resolution X-ray diffraction was used to characterize the epitaxial layers. The Al composition of 2.8% was obtained by assuming the Bragg’s formula and Vegard’s law. Spectral response measurement of the diodes has been employed to investigate the temperature dependence of the band gap of In1−xAlxSb alloys in the range between 77 K and 260 K. The calculated results for energy gap of InAlSb were in good agreement with the available data and our experimental observation.

In light of the proposed equivalent method, a three-dimensional structural modeling of InSb infrared focal plane arrays (IRFPAs) is created, and the simulated strain distribution is identical to the deformation distribution on the top surface of InSb IRFPAs. After comparing the deformation features at different regions with the structural characteristics of IRFPAs, we infer that the flatness of InSb IRFPAs will be improved with a thinner indium bump array, and this inference is verified by subsequent simulation results. That is, when the diameter of indium bump is smaller than 20 μm, the simulated Z-components of strain on the whole top surface of InSb IRFPAs is uniform, and the deformation amplitude is small. When the diameter of indium bump is larger than 28 μm, the simulated Z-components of strain increases rapidly with the thicker indium bump, and the flatness of InSb IRFPAs is worsened rapidly. According to the changing trend of deformation amplitude with diameters of indium bump, and employing element pitches normalization method, a design rule of indium bump is proposed. That is, when the diameter of indium bump is shorter than 0.4 times the element pitch, the flatness of InSb IRFPAs is in an acceptable range. This design rule was supported by different IRFPAs with different formats delivered by several main research groups for achieving a longer cycling life.

A higher fracture probability appearing in indium antimonide (InSb) infrared focal plane arrays (IRFPAs) subjected to the thermal shock test, restricts its final yield. In light of the proposed equivalent method, where a 32 × 32 array is employed to replace the real 128 × 128 array, a three-dimensional modeling of InSb IRFPAs is developed to explore its deformation rules. To research the damage degree to the mechanical properties of InSb chip from the back surface thinning process, the elastic modulus of InSb chip along the normal direction is lessened. Simulation results show when the out-of-plane elastic modulus of InSb chip is set with 30% of its Young’s modulus, the simulated Z-components of strain distribution agrees well with the top surface deformation features in 128 × 128 InSb IRFPAs fracture photographs, especially with the crack origination sites, the crack distribution and the global square checkerboard buckling pattern. Thus the Z-components of strain are selected to explore the deformation rules in the layered structure of InSb IRFPAs. Analyzing results show the top surface deformation of InSb IRFPAs originates from the thermal mismatch between the silicon readout integrated circuits (ROIC) and the intermediate layer above, made up of the alternating indium bump array and the reticular underfill. After passing through both the intermediate layer and the InSb chip, the deformation amplitude is reduced firstly from 2.23 μm to 0.24 μm, finally to 0.09 μm. Finally, von Mises stress criterion is employed to explain the causes that cracks always appear in the InSb chip.

Higher fracture probability, appearing in large format InSb infrared focal plane arrays detector under thermal shock loadings, limits its applicability and suitability for large format equipment, and has been an urgent problem to be solved. In order to understand the fracture mechanism and improve the reliability, three dimensional modeling and stress analysis of large format InSb detector is necessary. However, there are few reports on three dimensional modeling and simulation of large format InSb detector, due to huge meshing numbers and time-consuming operation to solve. To solve the problems, basing on the thermal mismatch displacement formula, an equivalent modeling method is proposed in this paper. With the proposed equivalent modeling method, employing the ANSYS software, three dimensional large format InSb detector is modeled, and the maximum Von Mises stress appearing in InSb chip dependent on array format is researched. According to the maximum Von Mises stress location shift and stress increasing tendency, the adaptability range of the proposed equivalent method is also derived, that is, for 16 × 16, 32 × 32 and 64 × 64 format, its adaptability ranges are not larger than 64 × 64, 256 × 256 and 1024 × 1024 format, respectively. Taking 1024 × 1024 InSb detector as an example, the Von Mises stress distribution appearing in InSb chip, Si readout integrated circuits and indium bump arrays are described, and the causes are discussed in detail. All these will provide a feasible research plan to identify the fracture origins of InSb chip and reduce fracture probability for large format InSb detector.

We have successfully grown a new ordered langasite structure piezoelectric single crystal Ca3TaGa3Si2O14 (CTGS) using the Czochralski (CZ) method. The single crystal structure was investigated by X-ray powder diffraction (XRPD) experiments and showed that the CTGS single crystals had a single phase and had the same structure as the La3Ga5SiO14 (LGS) crystal. The transmittance spectra from 190 to 3200 nm were measured and the transmittance of CTGS crystal was about 85% above 350 nm. The specific heat of the crystal has been measured to be 0.52 J/g K at room temperature. The thermal expansion coefficients perpendicular and parallel to Z direction has been measured to be 5.2×10−6 and 3.7×10−6/K between 298.15 and 450 K by a thermomechanical analyzer (TMA).