Publications by authors named "Shihao Cheng"

Although powered prosthetic legs have enabled more biomimetic joint kinematics during steady-state activities like walking and stair climbing, transitions between these activities are usually handled by discretely switching controllers without considering biomimicry or the distinct role of the leading leg. This study introduces two data-driven, phase-based kinematic control approaches for seamless inter-leg transitions (i.e.

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Annual net ecosystem productivity (NEP), the amount of net carbon sequestration during a year, serves as the basis of terrestrial carbon sink. Quantifying the spatial variations of NEP and its trend would enhance our understandings on the response and adaption of ecosystems to environmental change, which also serves for the regional carbon management targeting at carbon neutrality. Based on process-based model and data-driven model simulating NEP, we selected the optimal simulating NEP mostly representing NEP spatial variations with multiple site eddy covariance measurements to develop the spatial downscaling method and generate high resolution NEP data of China, which was used to examine the spatial variations of NEP and its trend and driving factors during 2000-2017.

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This paper presents a transfer learning method to enhance locomotion intent prediction in novel transfemoral amputee subjects, particularly in data-sparse scenarios. Transfer learning is done with three pre-trained models trained on separate datasets: transfemoral amputees, able-bodied individuals, and a mixed dataset of both groups. Each model is subsequently fine-tuned using data from a new transfemoral amputee subject.

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The skeletal transformations of diterpenoid forskolin were achieved by employing an oxidative rearrangement strategy. A library of 36 forskolin analogues with structural diversity was effectively generated. Computational analysis shows that 12 CTD compounds with unique scaffolds and ring systems were produced during the course of this work.

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Article Synopsis
  • The FGFR signaling pathway is crucial for processes like cell growth and movement, and targeting it with inhibitors may provide treatment options for cancers with FGFR mutations.
  • The study identified a promising compound that showed strong anti-cancer effects against various cancer cell lines carrying FGFR mutations, with effective concentrations ranging from 6.4-10.4 nM.
  • In animal models, this compound demonstrated excellent anti-tumor activity, achieving a tumor growth inhibition of 99.1% at a low dosage, indicating its potential as a therapeutic agent for FGFR mutant tumors.
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Robotic knee-ankle prostheses have often fallen short relative to passive microprocessor prostheses in time-based clinical outcome tests. User ambulation endurance is an alternative clinical outcome metric that may better highlight the benefits of robotic prostheses. However, previous studies were unable to show endurance benefits due to inaccurate high-level classification, discretized mid-level control, and insufficiently difficult ambulation tasks.

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One of the primary benefits of emerging powered prosthetic legs is their ability to facilitate step-over-step stair ascent by providing positive mechanical work. Existing control methods typically have distinct steady-state activity modes for walking and stair ascent, where activity transitions involve discretely switching between controllers and often must be initiated with a particular leg. However, these discrete transitions do not necessarily replicate able-bodied joint biomechanics, which have been shown to continuously adjust over a transition stride.

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Passive prosthetic legs require undesirable compensations from amputee users to avoid stubbing obstacles and stairsteps. Powered prostheses can reduce those compensations by restoring normative joint biomechanics, but the absence of user proprioception and volitional control combined with the absence of environmental awareness by the prosthesis increases the risk of collisions. This article presents a novel stub avoidance controller that automatically adjusts prosthetic knee/ankle kinematics based on suprasensory measurements of environmental distance from a small, lightweight, low-power, low-cost ultrasonic sensor mounted above the prosthetic ankle.

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Mycobacterium tuberculosis infections still pose a serious threat to human health. Combination therapies are effective medical solutions to the problem. Mycobacterium tuberculosis is an intracellular pathogen that mainly depends on a virulence factor (Mycobacterium tuberculosis protein tyrosine phosphatase B, MptpB) for its survival in the host.

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A ring distortion strategy was applied to the synthesis of a series of intramolecular cross-coupled analogues of forskolin 1. Treatment with palladium acetate, forskolin underwent an intramolecular cross-coupling reaction to generate a novel cycloalkene ether 2 in 85% yield. Under the same conditions, a series of forskolin ester analogues 4a-4d were prepared from 1-OH ester derivatives of forskolin 3a-3d in 85-93% yields.

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Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) is an important virulence factor that blocks the host immune response and facilitates M. tuberculosis growth in host cells. MptpB inhibitors are potential components of tuberculosis combination treatment.

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ABCA3 (ATP-binding cassette class A3) is a transmembrane transporter that plays a positive role in chronic pulmonary inflammation by regulating lipid metabolism. However, it is not completely clear whether ABCA3 and its signaling factors are involved in chronic pulmonary inflammation induced by the combination of CSE (cigarette smoke extract) and LPS (lipopolysaccharide). In this study, we used the method of combining CSE and LPS which was widely used to study lung inflammation-related diseases and has been proven effective in our group's studies to create in vivo and in vitro pulmonary inflammation models.

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Although emerging powered prostheses can enable people with lower-limb amputation to walk and climb stairs over different task conditions (e.g., speeds and inclines), the control architecture typically uses a finite-state machine to switch between activity-specific controllers.

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Covering: 2013-2022.Chemical diversification of natural products is an efficient way to generate natural product-like compounds for modern drug discovery programs. Utilizing ring-distortion reactions for diversifying natural products would directly alter the core ring systems of small molecules and lead to the production of structurally complex and diverse compounds for high-throughput screening.

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RhoA protein is a small GTPase that acts as a molecular switch. When bound to guanosine triphosphate (GTP), RhoA can activate several key signal pathways. Recently, nanobody Rh57 specific binding with GTP bound active RhoA was discovered and developed as a BRET biosensor without cytotoxicity.

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Red fluorescent proteins (RFPs) are powerful tools used in molecular biology research. Although RFP can be easily monitored in vivo, manipulation of RFP by suitable nanobodies binding to different epitopes of RFP is still desired. Thus, it is crucial to obtain structural information on how the different nanobodies interact with RFP.

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Current supervised learning or deep learning-based activity recognition classifiers can achieve high accuracy in recognizing locomotion activities. Most available techniques use a high-dimensional space of features, e.g.

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Green fluorescent protein (GFP) and its derivatives are widely used in biomedical research, and the manipulation of GFP-tagged proteins by GFP-specific binders is highly desired. However, structural information on how these binders bind with GFP is still lacking. In this study, we determined the crystal structure of the nanobody Nb2 complexed with superfolder GFP (sfGFP) at a resolution of 2.

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An efficient and mild one-pot convergent synthesis protocol has been developed for benzo[]oxazolo[3,4-][1,4]oxazin-1-one derivatives through the Mitsunobu reaction and sequential cyclization. Various tricyclic fused benzoxazinyl-oxazolidinones (20 examples) were obtained in good to excellent yields and high enantioselectivities with facile operation. Furthermore, four stereoisomers were afforded respectively in high ee values (>97.

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Modification of platinum (II) into lipophilic platinum (IV) compounds by introducing biologically active molecules were widely employed to develop new platinum-based prodrugs in the past decade. In this paper, two chlorambucil platinum (IV) complexes, CLB-Pt and CLB-Pt-CLB, were synthesized and displayed very potent antiproliferative activity against all the tested cancer cell lines, such as A549, HeLa and MCF-7, especially to treat the well-known refractory triple-negative breast cancer. CLB-Pt-CLB significantly improved cell-killing effect in triple-negative subtype MDA-MB-231 cells, and showed much stronger cytotoxicity than either monotherapy or combination of cisplatin and chlorambucil.

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