The emerging Ruddlesden−Popper two-dimensional perovskite (2D PVK) has recently joined the family of 2D semiconductors as a potential competitor for building van der Waals (vdW) heterostructures in future optoelectronics. However, to date, most of the reported heterostructures based on 2D PVKs suffer from poor spectral response that is caused by intrinsic wide bandgap of constituting materials. Herein, a direct heterointerface bandgap (∼0.4 eV) between 2D PVK and ReS 2 is demonstrated. The strong interlayer coupling reduces the energy interval at the heterojunction region so that the heterostructure shows high sensitivity with the spectral response expanding to 2000 nm. The large type-II band offsets exceeding 1.1 eV ensure fast photogenerated carriers separation at the heterointerface. When this heterostructure is used as a self-driven photodetector, it exhibits a record high detectivity up to 1.8 × 10 14 Jones, surpassing any reported 2D selfdriven devices, and an impressive external quantum efficiency of 68%.

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This study is aimed at definition of the safe and dangerous zone for screw placement with Stoppa approach for rapid identification during operation and a new way for the studies on the “safe zone.” Pelvic CT data of 84 human subjects were recruited to reconstruct the three-dimensional (3D) models. The distances between the edges of the “safe zone,” “dangerous zone,” and specific anatomic landmarks such as the obturator canal and the pelvic brim were precisely measured, respectively. The results show that the absolute “dangerous zone” was from the pelvic brim to 3.07 cm below it and within 2.86 cm of the obturator canal, while the region 3.56 cm below the pelvic brim or 3.85 cm away from the obturator canal was the absolute “safe zone” for screw placement. The region between the absolute “safe zone” and the absolute “dangerous zone” was the relatively “dangerous zone.” As a conclusion, application of computer-assisted 3D modeling techniques aids in the precise measurement of “safe zone” and “dangerous zone” in combination with Stoppa incision. It was not recommended to place screws on the absolute dangerous zone, while, for the relatively “dangerous zone,” it depends on the individual variations in bony anatomy and the fracture type.

A single device with switchable functions is highly attractive to the growing demands of complex optoelectronics. However, most of the currently reported devices either exhibit a lack of multifunction operation or require complex electrode configurations with limited performances. Here, a new concept of a functionalized‐black phosphorus (f‐BP)/MoS2 heterojunction is proposed, which enables the coexistence of an optoelectronic memory and a detector in a single device. The oxidation‐induced artificial‐traps on the BP surface result in a gate‐modulated photogating effect, so that the device can be freely switched between memory and detector by simply changing the back‐gate voltage. In the memory model, the device has an ultra‐long storage time (10 years), an ultra‐high on/off ratio (3.5 × 107), and outstanding multi‐bit storage (≈90 states), while in the detector model, the device still exhibits a fast response (130/260 µs), an impressive responsivity (22.2 A W−1), and self‐driven broadband detection (ultraviolet to near‐infrared). Most importantly, the highly anisotropic BP enables fast NIR polarization resolution with a maximum polarization ratio of 6.98 at 1064 nm.