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Bioactive peptides play important roles in various biological processes. However, the traditional methods for profiling the peptide-interacting proteins require modifications to the peptide molecules, often leading to false identifications. We found that the interaction between peptide ligands and protein receptors induced significant changes in the abundance of the interacting proteins, which is a signature indicating the interaction and providing complementary information for use in the classical thermal proteome profiling (TPP) technique. Herein, we developed a novel Peptide-ligand-induced Abundance Change of proTeinS (PACTS)-assisted TPP strategy for the identification of peptide-interacting proteins based on the peptide-ligand-induced change in protein abundance. The utility and efficacy of this approach were demonstrated by the identification of the interaction of the protein 3-phosphoinositide-dependent protein kinase 1 (PDPK1) and PDPK1-interacting fragment (PIF) pair and by large-scale profiling of the interacting proteins of PIF. The PACTS-assisted TPP approach was applied to describe the interactome of amyloid beta (Aβ) 1-42 in THP-1 cells and resulted in the identification of 103 interacting proteins. Validation experiments indicated that Aβ1-42 interacted directly with fatty acid synthase and inhibited its enzymatic activity, providing insights into fatty acid metabolic disorders in Alzheimer's disease (AD). Overall, PACTS-assisted TPP is an efficient approach, and the newly identified Aβ-interacting proteins provide rich resources for the research on AD.

In this paper, the influence of different opening ratios and different opening directions of the windows on the natural smoke exhaust was studied through a series of real fire experiments and simulation analysis. Increasing the open area of the window could effectively improve the overall smoke exhaust effect. When the top windows were open and the opening ratio increased from 19.2% to 24.3%, the optical density was decreased by 12.4%. The average smoke exhaust rate per unit area of the window did not change significantly. Increasing the area of the natural smoke exhaust window could effectively increase the smoke exhaust rate and improve the overall effect of smoke extraction. When the top windows were open, the temperature rise on the top floor was 30.8%–47.5% lower while the visibility was 16.8%–21.9% higher than that when the side windows were open.

Vertical shafts are common structures in buildings, which accelerate smoke spread in fires due to stack effect. In this study, fire smoke movement and distribution in a ventilation shaft were studi...

Complex brain circuitry with feedforward and feedback systems regulates neuronal activity, enabling neural networks to process and drive the entire spectrum of cognitive, behavioral, sensory, and motor functions. Simultaneous orchestration of distinct cells and interconnected neural circuits is underpinned by hundreds of synaptic adhesion molecules that span synaptic junctions. Dysfunction of a single molecule or molecular interaction at synapses can lead to disrupted circuit activity and brain disorders. Neuroligins, a family of cell adhesion molecules, were first identified as postsynaptic-binding partners of presynaptic neurexins and are essential for synapse specification and maturation. Here, we review recent advances in our understanding of how this family of adhesion molecules controls neuronal circuit assembly by acting in a synapse-specific manner.

Blasticidin S is a peptidyl nucleoside antibiotic. Its biosynthesis involves a cryptic leucylation and two leucylated intermediates, LDBS and LBS, have been found in previous studies. Leucylation has been proposed to be a new self-resistance mechanism during blasticidin S biosynthesis, and the leucyl group was found to be important for the methylation of β-amino group of the arginine side chain. However, the responsible enzyme and its associated mechanism of the leucyl transfer process remain to be elucidated. Here, we report results investigating the leucyl transfer step forming the intermediate LDBS in blasticidin biosynthesis. A hypothetical protein, BlsK, has been characterized by genetic and in vitro biochemical experiments. This enzyme catalyzes the leucyl transfer from leucyl-transfer RNA (leucyl-tRNA) to the β-amino group on the arginine side chain of DBS. Furthermore, BlsK was found to contain an iron-sulfur cluster that is necessary for activity. These findings provide an example of an iron-sulfur protein that catalyzes an aminoacyl-tRNA (aa-tRNA)-dependent amide bond formation in a natural product biosynthetic pathway.

Introduction: Coronavirus disease 2019 (COVID-19) was declared a global pandemic in March 2020. Since then, several studies have found COVID-19 patients with recurrent viral polymerase chain reaction (PCR) positivity. Methods: On May 6, 2021, an exhaustive literature search of the Web of Science, PubMed, Cochrane Library, Chinese National Knowledge Infrastructure databases, Embase, Wan Fang Data, VIP database, Sinomed database, BioRxiv, MedRxiv, and Research Square was conducted to find describing the laboratory indicators of recurrent and non-recurrent viral PCR positivity in patients with COVID-19. The data were statistically analyzed using STATA version 15.0. Results: In total, 22 studies—comprising 5154 laboratory-confirmed COVID-19 cases—were included in the analyses. Patients with less severe COVID-19 illness (i.e. those clinically classified as mild or common-type) seemed to exhibit recurrent PCR positivity more commonly than patients with more severe illness (i.e. those classified as severe or critical). There were also significant differences between the two groups in terms of the rates of headaches and dizziness, in addition to the levels of aspartate aminotransferase, C reactive protein, interleukin-6, and lactate dehydrogenase. Further, there were variations in the ratio of CD4+ T cells/CD8+ T cells on admission to the hospital. Conclusion: In comparison to COVID-19 patients with non-recurrent viral PCR positivity, patients with recurrent virus PCR positivity seem to experience more severe immune function suppression upon hospital admission.

This paper studied the stack effect in courtyards in buildings through the pressure difference between the top and the bottom in the courtyard through three-dimensional (3D) numerical simulations, which would provide engineering guidance for the fire protection design of courtyards in buildings. During the fire, the stronger the stack effect was, the pressure difference between the top and the bottom was more significant, the fire smoke reached the top of the courtyard more quickly, and the temperature and the smoke concentration at the top were influenced in a shorter time. The influence of the size of the courtyard in the stack effect was investigated. It was found that the stack effect was linearly negatively related to the width of the cross section W and the length of the cross section L, exponentially negatively related with the area of the cross section A, while it was exponentially positively related to the height of the courtyard H. The change in the walls without windows (W) affected ΔPmax and the stack effect more significantly compared with the change in walls with windows (L). When L/W ≤ 1, the stack effect was strengthened as L/W increased; when L/W > 1, the stack effect was weakened as L/W increased. The stack effect was the most significant when L/W = 1.

Background Severe fever with thrombocytopenia syndrome is caused by infection with the severe fever with thrombocytopenia syndrome virus. Methods Between April 2011 and December 2019, data on consecutive patients who were diagnosed with severe fever with thrombocytopenia syndrome were prospectively collected from five medical centers in China. The score of the death risk model was correlated with the platelet-to-lymphocyte ratio and the neutrophil-to-lymphocyte ratio. Multivariable Cox analyses were used to identify the independent factors associated with mortality. Results During the study period, 763 patients were diagnosed with severe fever with thrombocytopenia syndrome; 415 of these patients were enrolled in our study. We found that the neutrophil-to-lymphocyte ratio of the group that died was significantly higher on admission (P=0.007) than that of the group that survived, and the neutrophil-to-lymphocyte ratio showed a positive correlation with the score of the death risk model. Multivariate Cox regression suggested that a neutrophil-to-lymphocyte ratio greater than 5.4 was an independent risk factor for survival time (HR=6.767, P=0.011). Platelet-to-lymphocyte ratio did not show a special role in this study. Conclusions A neutrophil-to-lymphocyte ratio greater than 5.4 can increase the risk of death and decrease the survival time of patients. In summary, the neutrophil-to-lymphocyte ratio provides a supplementary means for effectively managing severe fever with thrombocytopenia syndrome (SFTS).

Severe hemorrhagic fever disease is caused by severe fever with thrombocytopenia syndrome virus (SFTSV) infection, which belongs to the Phlebovirus genus in the Bunyaviridae family. A comprehensive literature search of PubMed, Web of Science, Embase, Cochrane Library, Chinese National Knowledge Infrastructure databases, Wan Fang Data, Sinomed Database, and VIP database was conducted for articles which have described the clinical manifestation of deceased patients. Data from selected studies were pooled by using STATA VERSION 15.0 software. Finally, 29 articles comprising 4717 laboratory-confirmed SFTSV cases were included in this analysis. We found there were significant differences between the two groups for fatigue, headache, underlying disease, vomiting, diarrhea, skin bleeding, neurological symptoms, arrhythmia, diffuse intravascular coagulation, and multiple organ failure. There were some significant differences between the fatal and nonfatal groups, and we need to pay more attention to the above symptoms to distinguish between fatal and nonfatal patients.

Background Towards the end of December 2019, the Wuhan health commission declared an outbreak of clusters of pneumonia in patients. Sequencing indicated that this disease (COVID-19) was caused by a novel coronavirus (SARS-CoV-2). The outbreak of COVID-19 is currently still underway. Methods We recruited 75 SARS-CoV-2 infected patients admitted to the Center of Infectious Disease division 2 of Beijing Ditan Hospital from Jan 20 to Mar 20, 2020. Epidemiological, demographic, clinical, radiological features, laboratory data were analyzed. Results Of the 75 patients, 42(56%) patients were male and 33(44%) patients were female. The mean age of all patients was 41.5 ± 19.4 years. Male patients were more likely to become severe. There were 9 family clusters accounted for 44 patients. Patients classified as being severe had a higher frequency of fever upon admission than patients classified as moderate cases. For moderate patients, the median duration of viral shedding was 25(9.5, 42) days (range 1–63 days) from the first positive nucleic acid test compared to 14(9, 21.25) days (range 2–62 days) for severe cases. The difference between the two groups was statistically significant (p = 0.041). Cox regression analyses indicated that disease status and CRP were the factors that affect the duration of viral shedding. Virus clearance was significantly faster in severe patients compared to moderate patients(p = 0.011), and patients with CRP range in 2–10 times higher than upper limit of normal value had longer duration of viral shedding(p = 0.012). CRP and CD4 + T lymphocyte was negative correlated, and the relationship between CRP and CD4 + T lymphocyte was statistically significant (P = 0.003), with a correlation coefficient of -0.564. During the second week following the onset of illness, severe cases had higher WBC, NEU and CRP, but lower LYM, MON and EOS as compared with moderate cases (all P

Foam core sandwich materials are being widely used in structural engineering due to their advantages such as lightweight, high strength, and corrosion resistance. But the interfacial bond strength of foam core sandwich materials is weakened at elevated temperatures. In practice, the influence of high temperature cannot be ignored since the composites with foam are sensitive to the change in the environment. In this study, a series of sandwich double cantilever beams were tested at different temperatures to evaluate the effect of high temperatures on the interfacial fracture of the foam core sandwich materials. The temperature range studied was from 30 to 90℃, noting the glass transition temperatures are 85.7℃ for the composites and 72.1℃ for the foam core, respectively. In the meantime, the mode I interfacial crack propagation and its corresponding interfacial strain energy release rate were analyzed. Furthermore, an analytical model, considering the change in temperature, was proposed to predict the strain energy release rate of mode I interfacial facture of the foam core sandwich materials. The analytical results were found to be well matched with the experimental results.

U-shaped facade structure exists in a lot of high-rise buildings. A numerical simulation study on vertical fire spread in u-shaped structure was carried out. Influence of area and the width-depth ratio of the u-shaped structure on the fire spread was analyzed through fire spreading speed, stack effect and heat release rate. It was found that the fire spreading speed and stack effect in the u-shaped structure decreased as $A^{\ast}$ increased. When $A^{\ast}$ is larger than 0.0069, the influence of $A^{\ast}$ on the fire spreading speed and stack effect become very small. The maximum HRR was positively related with $A^{\ast}$ except for the case when $A^{\ast}$ is very small. As $K$ increased, the fire spreading speed and the maximum HRR first sharply decreased and then slowly decreased except for the case when K = 1. The relationship between stack effect and $K$ was very similar with the relationship between stack effect and $A^{\ast}$ , but in an opposite direction. When $K$ is larger than 2.25, the fire spreading speed, the stack effect and the maximum HRR did not change obviously with K.

A simple and convenient method for the preparation of hydrophilic polyurethane (PU) modified poly(vinylidene fluoride) (PVDF) membranes was developed. First, PU with hydroxyl functional end-groups was synthesized in one-step from polyethylene glycol 400(PEG 400) and isophorone diisocyanate (IPDI), and the raw product was directly added into casting solution without further purification to modify the PVDF membrane. The properties and performance of the prepared PU/PVDF membranes were characterized with Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), contact angle measurement, protein adsorption and filtration test. FTIR and XPS analyses indicate that PU with hydroxyl functional end-groups was successfully incorporated and enriched onto the membrane surface, while filtration test and SEM analysis show that more and larger pores were formed on the blended membranes, which significantly improves the permeation performance of the modified membranes, compared with the unmodified PVDF membrane. Results from protein adsorption and flux recovery experiment reveal that hydrophilic PU modification substantially improves the fouling resistant ability of the modified membranes. In addition, the effects of the molar ratio of PEG 400 to IPDI and the content of the PU additive on the properties and performance of the PU/PVDF membranes were also investigated.

The peptidyl nucleoside blasticidin S (BS) produced by Streptomyces griseochromogenes was the first non-mercurial fungicide used to prevent rice blast and increasingly used as a selection reagent in transgenic study. Acylation by addition of a leucine residue at the beta amine group of arginine side chain of demethylblasticidin S (DBS) has been proposed as a novel self-resistance to the cytotoxic biosynthetic intermediate. But the resultant product leucyldemethylblasticidin S (LDBS) has not been isolated as a metabolite, and LDBS synthetase activity remained to be demonstrated in S. griseochromogenes. In this study, we isolated LDBS in a BS heterologous producer S. lividans WJ2 upon the deletion of blsL, which encodes a S-Adenosyl methionine-dependent methyltransferase. Purified BlsL efficiently methylated LDBS at the delta N of beta-arginine to generate the ultimate intermediate LBS, but nearly didn't methylate DBS to final product BS. Above experiments demonstrated that LDBS is indeed an intermediate in BS biosynthetic pathway, and acylation of beta-amino group of arginine side chain is prerequisite for efficient guanidine N-methylation in addition to being a self-resistance mechanism.

We have achieved a tubular microcavity embedded InAs quantum dots by rolling the U-shaped InGaAs/GaAs strained bilayer based on GaAs substrate. Subsequently, micro-photoluminescence spectra were investigated at room temperature. Four sharp and equidistant peaks can be obviously observed, which are recognized as whispering gallery modes. Besides, the maximum value of quality factor is ∼1200 at 6.59 pW excitation power.

We have synthesized two low molecular weight organic molecules, PY and IN successfully, which selectively stain nucleolus and cytoplasm of living cells in 30 min, with a much lower uptake in the nucleus. Nucleic acids electrophoresis and digest test of ribonuclease indicate their markedly higher affinity for RNA, especially PY. Moreover their RNA localization in cells is further supported by digest test of ribonuclease, namely, the nucleolar fluorescence signal is distinctly lost upon treatment with RNase. And, the fact that live cells stained by PY and IN still possess physiological function can be confirmed: 1) MTT assay demonstrates that the mitochondria of cells stained remains its electron mediating ability, 2) Double assay of PY/IN and propidium iodide as well as trypan blue testing show that the membrane of cells stained still is intact. Importantly, compared with the only commercial RNA probe, SYTO RNA-Select, PY and IN exhibit much better photostability when continuously illuminated with 488 nm laser and mercury lamp. These results prove that PY and IN are very attractive staining reagents for visualizing RNA in living cells.

Reliable and accurate geolocation is essential for airborne and land-based remote sensing applications. The detection, discrimination, and remediation of unexploded ordnance (UXO) and other munitions and explosives of concern (MEC) using the currently available detection and geolocation technologies often yield unsatisfactory results, failing to detect all MEC present at a site or to discriminate between MEC and nonhazardous items. Thus, the goal of this paper is to design and demonstrate a high-accuracy geolocation methodology that will address centimeter-level relative accuracy requirements of a man-portable electromagnetic (EM) sensor system in open and impeded environments. The proposed system design is based on the tight quadruple integration of the Global Positioning System (GPS), the inertial measurement unit (IMU) system, the terrestrial radio-frequency (RF) system pseudolite (PL), and terrestrial laser scanning (TLS) to support high-accuracy geolocation for a noncontact EM mapping system in GPS-challenged environments. The key novel component of the proposed multisensor system is the integration of TLS that can provide centimeter-level positioning accuracy in a local frame and thus enables a GPS/IMU/PL-based navigation system to achieve both high absolute and relative positioning accuracy in GPS-impeded environments. This paper presents the concept design of the quadruple integration system, the algorithmic approach to data integration with a special emphasis on TLS integration with GPS/IMU/PL, and the performance assessment based on real data, where centimeter-level relative geolocation accuracy is demonstrated during the GPS signal blockage.

The micro-Raman spectra of as-grown area SQW GaAs/AlGaAs shows 281, 378 cm−1 for GaAs-like LO, AlAs-like LO of AlGaAs barrier, demonstrating two-mode behavior. For rolled-up microtubes, all LO modes shifted to lower frequencies.

Poor visibility had a great influence on the safety of the ship navigation, data shows more than 60% of ship collisions are caused by poor visibility, while radar is avoidance, collision avoidance an indispensable tool in particular the fog. Using radar we can get early warning collision risk by, so that we have more time for the give way vessel, collision avoidance, at the same time, we use VHF, AIS have dangerous ship on radar can also be identified and contact, coordination of lien, better collision effects can be achieved. In order to make the ship pilots to effective use of these instruments for collision avoidance, this article describes using these instruments under poor visibility conditions for some commonly-used method of collision avoidance. For ship pilots have drills boat collision reference in poor visibility conditions, with a view to preventing collisions to achieve a good effect, ensure the safety of maritime navigation.

In GPS-impeded environments, due to cumulative error characteristics of inertial sensors, a GPS/IMU system is unable to maintain high navigation accuracy during extended GPS outages. In particular, vegetated and urban environments present unique challenges in applications where high absolute and/or relative navigation accuracy is required. To remedy this deficiency, a method that integrates 3D laser ranging to deployable spherical targets with an inertial system to enable centimeter-level navigation accuracy of a mobile unit under heavy canopy is discussed here. This paper is focused on the requirements for geometry and spatial distribution of the spherical targets and their impact on the achievable navigation accuracy. The sensitivity analysis is performed based on simulations as well as the actual field test data.

In order to improve the market competitiveness of mobile phone manufacture companies in aspects of TQCS, based on the principle of virtual prototyping technology (VPT), a platform for developing the virtual prototype of mobile phone is put forward in this paper. The function model and the architecture of the platform are also described in detail. The ideas and some key technologies for implementing the platform are discussed in this paper. Finally, the validity of the development platform is demonstrated with a design example.