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Reproductive activities of six giant panda females (Ailuropoda melanoleuca) living in the Qinling Mountains of China (Shaanxi Province) were recorded from 1989 into early 1995. Data on mating and birth dates, litter size, cub sex and den use were collected for three of the pandas. At this site, pregnant females migrated to lower elevations in advance of other pandas to seek dens for birthing. One dam was videotaped in the den with her cub from birth to the end of the denning phase at 94 days of age. This cub was repeatedly handled during the dam's absences to obtain data on development and weight. During the early part of the denning phase, the cub was maintained on the dam's body virtually continuously. Postpartum fasting for up to 3 weeks was noted. Dams invariably moved cubs to new dens three or four times during the birth season. By the time cubs left the den at about 3± 4 months, they were fully furred and capable of surviving winter temperatures without further shelter. Reproductive parameters for the wild population fell within the range of values for captive pandas, based on information in the literature and in the giant panda studbook. The combined data on length of gestation, intervals between births, litter size and weight, infant development, and reproductive life span reveal a range of life-history variables that strongly resemble the Ursidae.

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of these perovskite-based photodetectors decreases to almost zero when the incident light wavelength is in the nearinfrared range due to the threshold of the material bandgap width at 760 nm. To improve the optical response of the perovskites in the near-infrared range, many chemical processings were explored, such as mixing of different perovskites [19][20][21][22] and doping of other materials. [23][24][25] Unfortunately, these chemical methods might induce the distortion of perovskite lattice and damage the device performance. [26] Metal nanostructures under light illumination can give rise to localized surface plasmon resonance (LSPR), [27,28] which induces strong light scattering and absorption. [29][30][31][32][33] Randomly inserting metal nanostructures into perovskite-based devices, such as solar cells [34][35][36][37] and photodetectors, [38,39] can improve photoresponse ability at the visible range. However, the response of these perovskite-based devices at the near-infrared range is still very weak.Here, we report a perovskite-based photodetector with high photoresponsivity in the near-infrared range that was fabricated on a well-defined plasmonic-functionalized multilayer substrate that was composed of arrays of Au nanosquares/SiO 2 spacer/ Au film. Due to the strong plasmonic coupling between the substrate and the incident light, a great amount of free carriers are generated in the perovskite film. As a consequence, a wider optical spectrum response and a better external quantum efficiency (EQE) in the near-infrared range were achieved, compared with the perovskite film on a usual Si/SiO 2 substrate. In addition, a sequentially tunable spectral response range of our device can be realized by varying the size of Au nanosquares.The schematic of our photodetector device is shown in Figure 1a, where the plasmonic substrate was designed to consist of three functional layers, arrays of Au nanosquares at the top, a SiO 2 dielectric spacer in the middle, and an Au film at the bottom. The perovskite (CH 3 NH 3 PbI 3 ) and hole-transporting medium (2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F 4 -TCNQ)-doped poly [bis(4-phenyl) (2,4,6-trimethylphenyl) amine] (PTAA) solution, abbreviated as HTM) were spin-coated onto the substrate. The HTM layer, incorporated between the substrate and CH 3 NH 3 PbI 3 layer, serves two functions: harvesting holes from the CH 3 NH 3 PbI 3 layer and insulating the transfer of hot electrons from the decay of LSPR. The incident Organic-inorganic hybrid perovskite photodetectors have been reported to possess superior optoelectronic properties, such as high sensitivity, ultrafast response, and capability of strongly absorbing the light in the visible range. While in the near-infrared range, the performances of these photodetectors deteriorate seriously, originating from the weak coupling of infrared light to the perovskites. In this study, an organic-inorganic hybrid perovskite photodetector on arrays of Au nanostructures is fabricated, which exhibits a remarkable photocur...