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Mid-infrared absorption spectroscopy plays an important role in molecule identification and quantification for widespread applications. Integrated photonics provides opportunities to perform spectroscopic sensing on-chip for the minimization of device size, cost, and power consumption. The integration of waveguides and photodetectors is an indispensable step toward the realization of these on-chip sensing systems. It is desired to extend the operating wavelengths of these on-chip sensing systems to the long-wave infrared (LWIR) range to utilize more molecular absorption fingerprints. However, the development of LWIR waveguide-integrated photodetectors faces challenges from both waveguide platforms due to the bottom cladding material absorption and photodetection technologies due to the low LWIR photon energy. Here, we demonstrate LWIR waveguide-integrated photodetectors through heterogeneous integration of graphene photodetectors and Si waveguides on CaF2 substrates. A high-yield transfer printing method is developed for flexibly integrating the waveguide and substrate materials to solve the bottom cladding material absorption issue. [https://www.selleckchem.com/products/Rapamycin.html Rapamycin molecular weight] The fabricated Si-on-CaF2 waveguides show low losses in the broad LWIR wavelength range of 6.3-7.1 μm. The graphene photodetector achieves a broadband responsivity of ∼8 mA/W in these low-photon-energy LWIR wavelengths under zero-bias operation with the help of waveguide integration and plasmonic enhancement. We further integrate the graphene photodetector with a Si-on-CaF2 folded waveguide and demonstrate on-chip absorption sensing using toluene as an example. These results reveal the potential of our technology for the realization of chip-scale, low-cost, and low-power-consumption LWIR spectroscopic sensing systems.Hypertrophic cardiomyopathy (HCM) is a disease of the myocardium caused by mutations in sarcomeric proteins with mechanical roles, such as the molecular motor myosin. Around half of the HCM-causing genetic variants target contraction modulator cardiac myosin-binding protein C (cMyBP-C), although the underlying pathogenic mechanisms remain unclear since many of these mutations cause no alterations in protein structure and stability. As an alternative pathomechanism, here we have examined whether pathogenic mutations perturb the nanomechanics of cMyBP-C, which would compromise its modulatory mechanical tethers across sliding actomyosin filaments. Using single-molecule atomic force spectroscopy, we have quantified mechanical folding and unfolding transitions in cMyBP-C domains targeted by HCM mutations that do not induce RNA splicing alterations or protein thermodynamic destabilization. Our results show that domains containing mutation R495W are mechanically weaker than wild-type at forces below 40 pN and that R502Q mutant domains fold faster than wild-type. None of these alterations are found in control, nonpathogenic variants, suggesting that nanomechanical phenotypes induced by pathogenic cMyBP-C mutations contribute to HCM development. We propose that mutation-induced nanomechanical alterations may be common in mechanical proteins involved in human pathologies.The detection of analytes and the sequencing of DNA using biological nanopores have seen major advances over recent years. The analysis of proteins and peptides with nanopores, however, is complicated by the complex physicochemical structure of polypeptides and the lack of understanding of the mechanism of capture and recognition of polypeptides by nanopores. In this work, we show that introducing aromatic amino acids at precise positions within the lumen of α-helical fragaceatoxin C (FraC) nanopores increased the capture frequency of peptides and largely improved the discrimination among peptides of similar size. Molecular dynamics simulations determined the sensing region of the nanopore, elucidated the microscopic mechanism enabling accurate characterization of the peptides via ionic current blockades in FraC, and characterized the effect of the pore modification on peptide discrimination. This work provides insights to improve the recognition and to augment the capture of peptides by nanopores, which is important for developing a real-time and single-molecule size analyzer for peptide recognition and identification.The successful development of targeted nanoparticle (NP)-based therapeutics depends on the effective conjugation of targeting ligands to the NP. However, conventional methods based on chemical reactive groups such as N-hydroxysuccinimide, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide, and maleimide have several limitations, including low binding efficiency, complex reaction methods, long reaction times, and reduced activity of the targeting ligand. In this study, we developed a novel method for conjugating targeting ligands to albumin NPs using the recently developed bacterial superglue the SpyTag/SpyCatcher (ST/SC) ligation system. This method involves a rapid one-step conjugation process with almost 100% efficiency. Albumin NPs conjugated to human epidermal growth factor receptor 2 (HER2) affibody molecules using the ST/SC system showed strong binding to HER2-overexpressing cells. In addition, NPs encapsulated with indocyanine green accumulated in cells overexpressing HER2 and exhibited superior photothermal treatment effects. Thus, surface functionalization of NPs using the ST/SC reaction may be used to develop new nanosystems that exhibit improved therapeutic benefits.Depression has drawn increasing attention from the public around the world in recent years. Studies have shown that liver injury caused by chronic stress is relevant to depression and neurotransmitter changes. It is essential to clarify the relationship between neurotransmitter changes and hepatic gene expression in depression. In this study, we used the chronic unpredictable mild stress (CUMS) model combined with UHPLC-MS to explore the changes of neurotransmitters in serum and hippocampus and to decipher the differential gene expression in the liver by using the RNA-Seq combined with multivariate statistical analysis. Compared with the control group, the levels of neurotransmitters including 5-hydroxytryptamine (5-HT), acetylcholine, glutamate (Glu), and dopamine (DA) in the hippocampus and 5-HT, norepinephrine, γ-aminobutyric acid (GABA), and 5-hydroxyindoleacetic acid in serum were significantly changed in the CUMS rats. The results of liver transcriptomic analysis and correlation analysis showed that the Glu, DA, 5-HT, and GABA were impacted by 68 liver genes which were mainly enriched in three pathways including circadian rhythm, serotonergic synapse, and p53 signaling pathway.