ABSTRACT
BACKGROUND: Prevotella heparinolytica is a Gram-negative bacterium that is commonly found in the oral, intestinal, and urinary tracts. It has been extensively studied in lower respiratory tract infections in horses, which has heparinolytic activity and can secrete heparinase and further induces virulence factors in cells and causes disease. However, no such cases have been reported in humans. CASE PRESENTATION: A 58-year-old male patient from China presented to the respiratory clinic in Suzhou with a productive cough producing white sputum for 20 days and fever for 3 days. Prior to this visit, a chest computed tomography scan was conducted, which revealed multiple patchy nodular opacities in both lungs. On admission, the patient presented with a temperature of 38.1 °C and a pulse rate of 110 beats per minute. Despite routine anti-infective treatment with moxifloxacin, his temperature fluctuated and the treatment was ineffective. The patient was diagnosed with Prevotella heparinolytica infection through metagenomic next-generation sequencing. Therefore, the antibiotics were switched to piperacillin-tazobactam in combination with ornidazole, which alleviated his symptoms; 1 week after discharge, the patient returned to the clinic for a follow-up chest computed tomography, and the opacities on the lungs continued to be absorbed. CONCLUSION: Prevotella heparinolytica is an opportunistic pathogen. However, it has not been reported in human pneumonia. In refractory pneumonia, measures such as metagenomic next-generation sequencing can be used to identify pathogens and help guide antibiotic selection and early support.
Subject(s)
Anti-Bacterial Agents , Prevotella , Tomography, X-Ray Computed , Humans , Male , Middle Aged , Prevotella/isolation & purification , Anti-Bacterial Agents/therapeutic use , Bacteroidaceae Infections/drug therapy , Bacteroidaceae Infections/microbiology , Bacteroidaceae Infections/diagnosis , Pneumonia, Bacterial/drug therapy , Pneumonia, Bacterial/microbiology , Pneumonia, Bacterial/diagnosis , Piperacillin, Tazobactam Drug Combination/therapeutic useABSTRACT
In a chamber-based digital PCR (dPCR) chip fabricated with polydimethylsiloxane (PDMS), bubble generation in the chambers at high temperatures is a critical issue. Here, we found that the main reason for bubble formation in PDMS chips is the too-high saturated vapor pressure of water at an elevated temperature. The bubbles should be completely prevented by reducing the initial pressure of the system to under 13.6 kPa to eliminate the effects of increased-pressure water vapor. Then, a cavity was designed and fabricated above the PCR reaction layer, and Parylene C was used as a shell covering the chip. The cavity was used for the negative generator in sample loading, PDMS degassing, PCR solution degassing in the digitization process and water storage in the thermal reaction process. The analysis was confirmed and finally achieved a desirable bubble-free, fast-digitization, valve-free and no-tubing connection dPCR.
Subject(s)
Dimethylpolysiloxanes , Steam , Polymerase Chain ReactionABSTRACT
Most hexagonal boron nitride (hBN) single-photon emitters (SPEs) studied to date suffer from variable emission energy and unpredictable polarization, two crucial obstacles to their application in quantum technologies. Here, we report an SPE in hBN with an energy of 2.2444 ± 0.0013 eV created via carbon implantation that exhibits a small inhomogeneity of the emission energy. Polarization-resolved measurements reveal aligned absorption and emission dipole orientations with a 3-fold distribution, which follows the crystal symmetry. Photoluminescence excitation (PLE) spectroscopy results show the predictability of polarization is associated with a reproducible PLE band, in contrast with the non-reproducible bands found in previous hBN SPE species. Photon correlation measurements are consistent with a three-level model with weak coupling to a shelving state. Our ab initio excited-state calculations shed light on the atomic origin of this SPE defect, which consists of a pair of substitutional carbon atoms located at boron and nitrogen sites separated by a hexagonal unit cell.
ABSTRACT
Accurate sensing and responding to physical microenvironment are crucial for cell function and survival, but the underlying molecular mechanisms remain elusive. Pollen tube (PT) provides a perfect single-cell model for studying mechanobiology since it's naturally subjected to complex mechanical instructions from the pistil during invasive growth. Recent reports have revealed discrepant PT behaviors between in vivo and flat, two-dimensional in vitro cultures. Here, we established the Stigma-style-transmitting tract (TT) Physical microenvironment Assay (SPA) to recapitulate pressure changes in the pistil. This biomimetic assay has enabled us to swiftly identify highly redundant genes, GEF8/9/11/12/13, as new regulators for maintaining PTs integrity during style-to-TT emergence. In contrast to normal growth on solid medium, SPA successfully phenocopied gef8/9/11/12/13 PT in vivo growth-arrest deficiency. Our results suggest the existence of distinct signaling pathways regulating in vivo and in vitro PT integrity maintenance, underscoring the necessity of faithfully mimicking the physical microenvironment for studying plant cell biology.
Subject(s)
Pollen Tube , Pollen , Pollen Tube/metabolism , Pollen/metabolism , Flowers/genetics , Pollination , PhenotypeABSTRACT
Numerous studies have shown that miRNAs play a crucial role in the investigation of complex human diseases. Identifying the connection between miRNAs and diseases is crucial for advancing the treatment of complex diseases. However, traditional methods are frequently constrained by the small sample size and high cost, so computational simulations are urgently required to rapidly and accurately forecast the potential correlation between miRNA and disease. In this paper, the DEJKMDR, a graph convolutional network (GCN)-based miRNA-disease association prediction model is proposed. The novelty of this model lies in the fact that DEJKMDR integrates biomolecular information on miRNA and illness, including functional miRNA similarity, disease semantic similarity, and miRNA and disease similarity, according to their Gaussian interaction attribute. In order to minimize overfitting, some edges are randomly destroyed during the training phase after DropEdge has been used to regularize the edges. JK-Net, meanwhile, is employed to combine various domain scopes through the adaptive learning of nodes in various placements. The experimental results demonstrate that this strategy has superior accuracy and dependability than previous algorithms in terms of predicting an unknown miRNA-disease relationship. In a 10-fold cross-validation, the average AUC of DEJKMDR is determined to be 0.9772.
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OBJECTIVES: Pulmonary embolism (PE) is a life-threatening complication that can occur in patients with lung cancer. In this study, we aimed to identify risk factors and examine the clinical characteristics of advanced lung cancer patients with PE. METHODS: We conducted a retrospective review of patients admitted to our two hospitals between January 2020 and June 2022. The case group consisted of patients with lung cancer and PE, and a closely matched control group was included to identify risk factors. Statistical analysis was conducted using R language. RESULTS: A total of 4957 patients were reviewed, and 162 patients (comprising 54 cases and 108 controls) were included in this study. The prevalence of lung cancer with PE in the study population was 1.08%. The majority of patients were male, and the most common histological subtype was adenocarcinoma (67%), followed by squamous cell carcinoma, small cell carcinoma, and poorly differentiated non-small cell lung cancer. The majority of patients had a high performance status (PS) score, with 50% experiencing respiratory failure (mainly hypoxia) and 33% with deep vein thrombosis (DVT). Forty-eight percent of patients were diagnosed with concurrent PE. Further analysis showed that PE was an independent predictor of poor survival, and a PS score of >1 was an independent risk factor for PE in patients with lung cancer. CONCLUSION: Our study provides valuable insights into the epidemiology and prognosis of PE in lung cancer patients and suggests that a poor ECOG PS, which has not been previously reported, is an independent risk factor for PE.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Pulmonary Embolism , Humans , Male , Female , Lung Neoplasms/complications , Lung Neoplasms/epidemiology , Case-Control Studies , Carcinoma, Non-Small-Cell Lung/complications , Cross-Sectional Studies , Pulmonary Embolism/diagnosis , Risk Factors , Retrospective StudiesABSTRACT
The interplay of nontrivial topology and superconductivity in condensed matter physics gives rise to exotic phenomena. However, materials are extremely rare where it is possible to explore the full details of the superconducting pairing. Here, we investigate the momentum dependence of the superconducting gap distribution in a novel Dirac material PdTe. Using high resolution, low temperature photoemission spectroscopy, we establish it as a spin-orbit coupled Dirac semimetal with the topological Fermi arc crossing the Fermi level on the (010) surface. This spin-textured surface state exhibits a fully gapped superconducting Cooper pairing structure below T_{c}â¼4.5 K. Moreover, we find a node in the bulk near the Brillouin zone boundary, away from the topological Fermi arc. These observations not only demonstrate the band resolved electronic correlation between topological Fermi arc states and the way it induces Cooper pairing in PdTe, but also provide a rare case where surface and bulk states host a coexistence of nodeless and nodal gap structures enforced by spin-orbit coupling.
ABSTRACT
Multi-walled carbon nanotubes (MWCNTs) with different oxygen functional groups were prepared from hot nitric acid reflux treatment. The acid-treated MWCNTs (a-MWCNTs) were introduced to negative active materials (NAMs) of lead-acid batteries (LABs) and the high-rate-partial-state-of-charge (HRPSoC) performance of the LABs was evaluated. A-MWCNTs with high quantities of carboxylic (COO-) and carbonyl (C[double bond, length as m-dash]O) functional groups significantly improve the lead sulfate (PbSO4) reduction to lead (Pb) and thereby improve HRPSoC cycle life. The addition of a-MWCNTs to NAMs is helpful for the formation of larger crystals of ternary lead sulfate (3BS). The improved LABs performance is due to the formation of a sponge crisscrossed rod-like structure at the negative plate in the presence of a-MWCNTs. This unique channels structure is conducive to the diffusion of the electrolyte into the negative plate and delays the PbSO4 accumulation during HRPSoC cycles. The HRPSoC cycle life with a-MWCNTs is significantly prolonged up to the longest cycles of 39 580 from 19 712. In conclusion, oxygen-containing groups on the a-MWCNTs showed significant influence on the curing process and forming process and then improved HRPSoC performance.
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BACKGROUND: Despite the obvious benefits of aerobic exercise for asthmatic patients, controversies persist. The current study evaluated the effectiveness of continuous aerobic exercise on lung function and quality of life of asthmatic patients. METHODS: We searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials databases up to May 2019 and included randomized controlled trials (RCTs) of asthmatic patients intervened with whole body continuous aerobic exercise (moderate intensity, at least 20 minutes and two times a week, over a minimum period of four weeks), in which the endpoint measures were lung function and asthma-related quality of life. A fixed-effects model (I2≤50%) or random-effects model (I2>50%) was applied to calculate the pooled effects according to the I2-and Chi-squared (χ2) test, funnel plots were quantified to present publication bias, and a P value <0.05 was statistically significant. RESULTS: Eventually, 22 trials conformed to the selection criteria. In the aerobic exercise group, the forced expiratory volume improved in one second (FEV1) (I2=10.2%, WMD: 0.12, P=0.011), peak expiratory flow (PEF) (I2=87.3%, WMD: 0.66, P=0.002), forced vital capacity (FVC) (I2=0.0%, WMD: 0.18, P<0.001), FVC/predict (I2=3.9%, WMD: 4.3, P=0.014), forced expiratory flow between 25% and 75% of vital capacity (FEF25-75%) (I2=0.0%, WMD: 9.6, P=0.005), Asthma Quality of Life Questionnaire (AQLQ) (I2=0.0%, WMD: 0.20, P=0.002), and Pediatric Asthma Quality of life Questionnaire (PAQLQ) (I2=72.1%, WMD: 0.81, P<0.001), respectively, while no statistical significance existed in FEV1%predict (I2=36.0%, WMD: 0.68, P=0.312) and FEV1/FVC ratio (I2=0.0%, WMD: 0.27, P=0.443) compared with the control group. When the exercise mode was taken into account, we observed significant improvement in FEV1, PEF, and FVC in the swimming (P<0.05) or indoor treadmill (P<0.05) training group. CONCLUSIONS: Our meta-analysis proved that regular continuous aerobic exercise benefits asthma patients on FEV1, PEF, FVC, FVC%pred, FEF25-75%, and quality of life, and was well tolerated, while there were no improvements in FEV1%pred and FEV1/FVC%. As such, swimming and treadmill training may be appropriate options.
ABSTRACT
CuCo2O4 was synthesized via a relatively simple method, and innovatively supported onto the activated carbon (AC) by calcination to obtain a novel heterogeneous catalyst (AC-CuCo2O4). Brilliant red 3BF (3BF) was selected as the probe compound to investigate the catalytic activity of AC-CuCo2O4 in the presence of peroxymonosulfate (PMS). The results showed that 98% removal rate could be achieved and the reaction rate constant (0.476 min-1) was 5.2 times greater than that of CuCo2O4 alone (0.091min-1), suggesting that the introduction of AC could greatly enhance the catalytic activity of pure CuCo2O4. Typically, the 3BF removal was as high as 96% after five cycles, showing the good stability of catalyst reuse. Additionally, the effects of the initial pH, catalyst dosage, PMS concentration and reaction temperature on the 3BF removal were investigated, demonstrating that AC-CuCo2O4 effectively remove 3BF over a wide pH range (5.0-10.0) and possessed temperature-tolerant performance. To further explore the 3BF removal mechanism, electron paramagnetic resonance technology combining with trapping agents was employed to confirm the involvement of reactive oxygen species including SO4â¢-, â¢OH, O2â¢- and 1O2, which distinctly differed from the reported CuCo2O4 for PMS activation. These findings provided an addition promising strategy in environmental remediation.
Subject(s)
Charcoal , Environmental Pollutants , Peroxides , CatalysisABSTRACT
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
ABSTRACT
Understanding the remarkable excitonic effects and controlling the exciton binding energies in two-dimensional (2D) semiconductors are crucial in unlocking their full potential for use in future photonic and optoelectronic devices. Here, we demonstrate large excitonic effects and gate-tunable exciton binding energies in single-layer rhenium diselenide (ReSe2) on a back-gated graphene device. We used scanning tunneling spectroscopy and differential reflectance spectroscopy to measure the quasiparticle electronic and optical bandgap of single-layer ReSe2, respectively, yielding a large exciton binding energy of 520 meV. Further, we achieved continuous tuning of the electronic bandgap and exciton binding energy of monolayer ReSe2 by hundreds of milli-electron volts through electrostatic gating, attributed to tunable Coulomb interactions arising from the gate-controlled free carriers in graphene. Our findings open a new avenue for controlling the bandgap renormalization and exciton binding energies in 2D semiconductors for a wide range of technological applications.
ABSTRACT
The exploitation of highly efficient and reusable catalysts based on peroxymonosulfate (PMS) activation has attracted considerable attention in the environmental catalysis field. Herein, Co-doped graphitic carbon (Co-GC) on nitrogen-doped carbon (NC@Co-GC) was constructed and first employed as an efficient heterogeneous catalyst to activate PMS for the removal of organic contaminants. Coupled with only 0.5 mM PMS, NC@Co-GC could achieve 96.7% removal of reactive brilliant red within 14 min. Most importantly, the rate constant of NC@Co-GC was 7 times higher than that of commercial Co3O4. Additionally, NC@Co-GC with PMS could also exhibit high elimination rates of other dyes and organic contaminants including 8-hydroxy-quinoline, ciprofloxacin and phenol for the same condition. Benefiting from the magnetic properties, the catalyst could be separated and recycled by a magnet. Through the combination of the electron paramagnetic resonance (EPR) technology and the radical quenching experiments, it could be concluded that four types of ROS including 1O2, SO4Ë-, ËOH and O2Ë- were involved and 1O2 played a dominant role in 3BF elimination. Interestingly, the catalytic efficiency remarkably improved and the rate constant increased by 3-fold in the presence of Cl-, which always played a negative role and functioned as a ROS scavenger in a previous study. This report will inspire new studies for the development of a Co-based catalyst with both high efficiency and extraordinary reusability.
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Tungsten-based monolayer transition metal dichalcogenides host a long-lived "dark" exciton, an electron-hole pair in a spin-triplet configuration. The long lifetime and unique spin properties of the dark exciton provide exciting opportunities to explore light-matter interactions beyond electric dipole transitions. Here we demonstrate that the coupling of the dark exciton and an optically silent chiral phonon enables the intrinsic photoluminescence of the dark-exciton replica in monolayer WSe2. Gate and magnetic-field dependent PL measurements unveil a circularly-polarized replica peak located below the dark exciton by 21.6 meV, equal to Eâ³ phonon energy from Se vibrations. First-principles calculations show that the exciton-phonon interaction selectively couples the spin-forbidden dark exciton to the intravalley spin-allowed bright exciton, permitting the simultaneous emission of a chiral phonon and a circularly-polarized photon. Our discovery and understanding of the phonon replica reveals a chirality dictated emission channel of the phonons and photons, unveiling a new route of manipulating valley-spin.
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Organic phase change materials (PCMs) have great potential in thermal protection applications but they suffer from high volumetric change and easy leakage, which require "leak-proof" packaging materials with low thermal conductivity. Herein, we successfully modify SiO2 through a simple 2-step method consisting of n-hexane activation followed by short-chain alkane silanization. The modified SiO2 (M-SiO2) exhibits superior hydrophobic property while maintaining the intrinsic high porosity of SiO2. The surface modification significantly improves the absorption rate of RT60 in SiO2 by 38%. The M-SiO2/RT60 composite shows high latent heat of 180 J·g-1, low thermal conductivity of 0.178 W·m-1·K-1, and great heat capacity behavior in a high-power thermal circuit with low penetrated heating flow. Our results provide a simple approach for preparing hydrophobic SiO2 with high absorption of organic PCM for thermal protection applications.
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Realizing magnetism in graphene nanostructures is a decade-long challenge. The magnetic edge state and half metallicity in zigzag graphene nanoribbons are particularly promising (Son et al 2006 Nature 444 347). However, its experimental realization has been hindered by the stringent requirement of the mono-hydrogenated zigzag edge. Using first-principle calculations, we predict that free-carrier doping can overcome this challenge and realize ferromagnetism and half-metallicity in narrow graphene nanoribbons of general types of edge structures. This magnetism exists within the density range of gate-doping experiments (~1013 cm-2) and has large spin polarization energy up to 17 meV per carrier, which induces a Zeeman splitting equivalent to an external magnetic field of a few hundred Tesla. Moreover, we trace the formation of this edge-insensitive magnetism to the quantum confinement of the electronic state near the band edge and reveal the scaling law of magnetism versus the ribbon width. Our findings suggest that combining doping with quantum confinement could be a general tool to realize transition-metal-free magnetism in light-element nanostructures.
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Amorphous molybdenum sulfides (a-MoSx) have been demonstrated as economic and efficient hydrogen evolution catalysts for water splitting. Further improvements of their hydrogen evolution reaction (HER) activities could be achieved by coupling them with appropriate electron transfer intermediates via interfacial engineering. In this study, a novel ternary composite electrode comprising PbTe quantum dots (QDs), a-MoSx and TiO2 nanotube arrays (TNAs) was successfully fabricated by a facile combination of successive ionic layer adsorption and reaction (SILAR) and electrodeposition routes. Investigation of the microstructures and electrocatalytic properties of the a-MoSx/PbTe QD/TNA hybrid material show that PbTe QDs can work as electron temporary storage and electron transfer intermediates between the electrocatalyst a-MoSx and electrode-based material TiO2 that significantly lower the impedance of electrode process, enhance the energy band bending at the interface between the electrolyte and electrode surface, and increase the electrochemically active surface area. The electron interphase crossing from a-MoSx to electrolyte and electron transport inside the electrode are greatly strengthened. The ternary PbTe@MoSx/TNA electrode demonstrates lowered onset potential and Tafel slope and superior electrocatalytic activity and cyclic stability towards HER.
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BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pleiotropic pro-inflammatory mediator that is involved in the progression of rheumatoid arthritis (RA). Previously, we demonstrated a small molecule compound 3-[(biphenyl-4-ylcarbonyl) carbamothioyl] amino benzoic acid (Z-590) could inhibit MIF activity with docking-based virtual screening and experimental evaluation. METHODS: The LPS activated RAW264.7 macrophage cells were used to determine the anti-inflammatory effects of Z-590 in vitro. A rat adjuvant-induced arthritis (AIA) model was used to determine the anti-arthritic effects of Z-590 in vivo. RESULTS: MIF inhibitor Z-590 significantly inhibited the production of NO, TNF-α and IL-6 in LPS-activated RAW 264.7 macrophage cells and markedly inhibited LPS-induced expression of TNF-α, IL-6, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Z-590 also significantly reduced paw edema, serum level of TNF-α, IL-6 and spleen index in the adjuvant-induced arthritis (AIA) rat model. Furthermore, Z-590 markedly ameliorated joint inflammation and articular cartilage damage in AIA rat model. CONCLUSION: MIF inhibitor Z-590 possesses potent anti-arthritic activity through suppression of macrophage activation, and could be a potential therapeutic treatment for RA.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Arthritis, Experimental/metabolism , Intramolecular Oxidoreductases/antagonists & inhibitors , Macrophage Activation/drug effects , Macrophage Migration-Inhibitory Factors/antagonists & inhibitors , Macrophages/metabolism , Animals , Arthritis, Experimental/drug therapy , Arthritis, Experimental/pathology , Interleukin-6/metabolism , Intramolecular Oxidoreductases/metabolism , Macrophage Migration-Inhibitory Factors/metabolism , Macrophages/pathology , Mice , RAW 264.7 Cells , Tumor Necrosis Factor-alpha/metabolismABSTRACT
Bilayer van der Waals (vdW) heterostructures such as MoS2/WS2 and MoSe2/WSe2 have attracted much attention recently, particularly because of their type II band alignments and the formation of interlayer exciton as the lowest-energy excitonic state. In this work, we calculate the electronic and optical properties of such heterostructures with the first-principles GW+Bethe-Salpeter Equation (BSE) method and reveal the important role of interlayer coupling in deciding the excited-state properties, including the band alignment and excitonic properties. Our calculation shows that due to the interlayer coupling, the low energy excitons can be widely tuned by a vertical gate field. In particular, the dipole oscillator strength and radiative lifetime of the lowest energy exciton in these bilayer heterostructures is varied by over an order of magnitude within a practical external gate field. We also build a simple model that captures the essential physics behind this tunability and allows the extension of the ab initio results to a large range of electric fields. Our work clarifies the physical picture of interlayer excitons in bilayer vdW heterostructures and predicts a wide range of gate-tunable excited-state properties of 2D optoelectronic devices.
ABSTRACT
Vertical dielectric screening is a fundamental parameter of few-layer van der Waals two-dimensional (2D) semiconductors. However, unlike the widely-accepted wisdom claiming that the vertical dielectric screening is sensitive to the thickness, our first-principles calculation based on the linear response theory (within the weak field limit) reveals that this screening is independent of the thickness and, in fact, it is the same as the corresponding bulk value. This conclusion is verified in a wide range of 2D paraelectric semiconductors, covering narrow-gap ones and wide-gap ones with different crystal symmetries, providing an efficient and reliable way to calculate and predict static dielectric screening of reduced-dimensional materials. Employing this conclusion, we satisfactorily explain the tunable band gap in gated 2D semiconductors. We further propose to engineer the vertical dielectric screening by changing the interlayer distance via vertical pressure or hybrid structures. Our predicted vertical dielectric screening can substantially simplify the understanding of a wide range of measurements and it is crucial for designing 2D functional devices.