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Accurately reconstructing 3D hand poses is a pivotal element for numerous Human-Computer Interaction applications. In this work, we propose SonicHand, the first smartphone-based 3D hand pose reconstruction system using purely inaudible acoustic signals. SonicHand incorporates signal processing techniques and a deep learning framework to address a series of challenges. First, it encodes the topological information of the hand skeleton as prior knowledge and utilizes a deep learning model to realistically and smoothly reconstruct the hand poses. Second, the system employs adversarial training to enhance the generalization ability of our system to be deployed in a new environment or for a new user. Third, we adopt a hand tracking method based on channel impulse response estimation. It enables our system to handle the scenario where the hand performs gestures while moving arbitrarily as a whole. We conduct extensive experiments on a smartphone testbed to demonstrate the effectiveness and robustness of our system from various dimensions. The experiments involve 10 subjects performing up to 12 different hand gestures in three distinctive environments. When the phone is held in one of the user's hands, the proposed system can track joints with an average error of 18.64 mm. [ABSTRACT FROM AUTHOR]

Ni‐catalyzed activation of C(sp2)−H bond remains an elusive challenge. Herein, we realized a Ni‐catalyzed selective activation of C(sp2)−H bond of formamides, which underwent addition reaction with internal alkynes to provide α,β‐unsaturated amide compounds in high yields. The protocol was featured by the cheap and nontoxic catalyst system. Preliminary mechanistic studies shed light on the reaction pathways. [ABSTRACT FROM AUTHOR]

In this study, the third-generation rhenium containing single crystal superalloy was brazed by mixed powder filler, in which the mixed powder filler was consisted of nickel-based powder filler and the superalloy powder with the same composition of the base metal. SEM and EPMA were used to analyze the influence of the proportion of the third-generation single crystal superalloy powder in the mixed filler on the microstructure of the joint, and the high temperature stress rupture properties of the brazed joint with four kinds of solder were tested. The result indicates that the microstructures and phase compositions of the Ni-based powder filler and mixed powder filler are both consisted of γ-Ni, γ′, CrB, Ni3B and M3B2 type boride, but the residue of the mixed powder filler is molten ball-type superalloy. With the thickness of brazing gap constant and increasing the ratio of the third-generation single crystal superalloy powder in the mixed filler, the precipitation of M3B2 type boride and low-melting point phases in the joint can be inhibited, and the distribution of borides becomes more uniform and the size becomes smaller, thus improving the uniformity of the composition and microstructure of the joint. When the proportion of alloy powder increased from 0% to 50%, the endurance life of the joint increased from 15 min to 34 hours. However, when the proportion of alloy powder increased to 60%, there are a lot of void defects in the joint, resulting in the endurance life of the joint decreased to 4 hours.

In the absence of directing auxiliaries, catalytic addition of nucleophiles to unactivated alkynes with accurate control of regioselectivity remains an ongoing challenge in organic chemistry. Herein, we realized a Ag‐catalysed regiospecific hydration process of unactivated alkynes. Computational investigations offered insights into the origin of the regiochemical outcome. The practicability and efficacy of the protocol was exemplified by its simple reaction conditions without incorporation of acidic additives, as well as the tolerance of a wide range of alkynes equipped with various functional groups, leading to the ketone products in up to 98 % yield. Direct modification of bioactive organic molecules and gram‐scale experiments further showcased the application potential of the strategy. The catalyst control principles are expected to advance efforts towards the development of general site‐selective addition of nucleophile to unsaturated substrates, removing the requirement for neighboring activating groups. [ABSTRACT FROM AUTHOR]

The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is attribute to the aggressive local invasion, distant metastasis and drug resistance of PDAC patients, which was strongly accelerated by epithelial–mesenchymal transition (EMT). In current study, we systematically investigate the role of ZNF263/RNF126 axis in the initiation of EMT in PDAC in vitro and vivo. ZNF263 is firstly identified as a novel transactivation factor of RNF126. Both ZNF263 and RNF126 were overexpressed in PDAC tissues, which were associated with multiple advanced clinical stages and poor prognosis of PDAC patients. ZNF263 overexpression promoted cell proliferation, drug resistance and EMT in vitro via activating RNF126 following by the upregulation of Cyclin D1, N‐cad, and MMP9, and the downregulation of E‐cad, p21, and p27. ZNF263 silencing contributed to the opposite phenotype. Mechanistically, ZNF263 transactivated RNF126 via binding to its promoter. Further investigations revealed that ZNF263 interacted with ZNF31 to coregulate the transcription of RNF126, which in turn promoted ubiquitination‐mediated degradation of PTEN. The downregulation of PTEN activated AKT/Cyclin D1 and AKT/GSK‐3β/β‐catenin signaling, thereby promoting the malignant phenotype of PDAC. Finally, the coordination of ZNF263 and RNF126 promotes subcutaneous tumor size and distant liver metastasis in vivo. ZNF263, as an oncogene, promotes proliferation, drug resistance and EMT of PDAC through transactivating RNF126. [ABSTRACT FROM AUTHOR]

[Objectives] Propeller noise and hydrodynamic noise are the key and difficult points of submarine noise control. Therefore,it is necessary to carry out propeller excitation force and hydrodynamic noise prediction research.[Methods] With the SUBOFF submarine and DTMB 4383 propeller as the calculation object,combined with the large eddy simulation turbulence model and the infinite element method,the change rule of the propeller excitation force in the non-uniform accompanying flow field of the submarine and the influence of the propeller on the surface pressure field of the submarine are analyzed. The ACTRAN acoustic calculation software is used to numerically predict the hydrodynamic noise performance of the integrated boat.[Results] The calculation results show that the components of the propeller excitation force have the same pulsation frequency,the pulsation peak is mainly the first-order leaf frequency,and the horizontal force pulsation and vertical force pulsation are greater than the thrust pulsation. The high pressure area exists at the bow,command station,tail and blade tip of submarine, which is the main contribution point of hydrodynamic noise. The hydrodynamic noise of the boat and propeller is mainly concentrated in the low frequency band,and the butterfly distribution is more obvious as the frequency increases. Compared with the propeller's full-body submarine,the sound pressure value of the submarine's characteristic point increases sharply due to the rotation of the propeller,and the variation of the radiated sound field is also large.[Conclusions] The research results can provide reference for the propeller design of the propeller.