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1.
Proc Natl Acad Sci U S A ; 119(32): e2111726119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914162

RESUMO

A large number of neutrophils infiltrate the lymph node (LN) within 4 h after Staphylococcus aureus skin infection (4 h postinfection [hpi]) and prevent systemic S. aureus dissemination. It is not clear how infection in the skin can remotely and effectively recruit neutrophils to the LN. Here, we found that lymphatic vessel occlusion substantially reduced neutrophil recruitment to the LN. Lymphatic vessels effectively transported bacteria and proinflammatory chemokines (i.e., Chemokine [C-X-C motif] motif 1 [CXCL1] and CXCL2) to the LN. However, in the absence of lymph flow, S. aureus alone in the LN was insufficient to recruit neutrophils to the LN at 4 hpi. Instead, lymph flow facilitated the earliest neutrophil recruitment to the LN by delivering chemokines (i.e., CXCL1, CXCL2) from the site of infection. Lymphatic dysfunction is often found during inflammation. During oxazolone (OX)-induced skin inflammation, CXCL1/2 in the LN was reduced after infection. The interrupted LN conduits further disrupted the flow of lymph and impeded its communication with high endothelial venules (HEVs), resulting in impaired neutrophil migration. The impaired neutrophil interaction with bacteria contributed to persistent infection in the LN. Our studies showed that both the flow of lymph from lymphatic vessels to the LN and the distribution of lymph in the LN are critical to ensure optimal neutrophil migration and timely innate immune protection in S. aureus infection.


Assuntos
Quimiocinas , Infiltração de Neutrófilos , Dermatopatias Bacterianas , Infecções Estafilocócicas , Animais , Quimiocinas/imunologia , Imunidade Inata , Inflamação/patologia , Linfa/imunologia , Linfonodos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Neutrófilos/citologia , Dermatopatias Bacterianas/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus
2.
Opt Express ; 32(10): 18044-18054, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858970

RESUMO

As a combination of direct detection and coherent detection technologies, self-coherent detection has the advantages of low cost and optical field recovery ability. However, most of the self-coherent detection techniques are limited to single sideband (SSB) signals. Recently, carrier-assisted differential detection (CADD) has been proposed to realize complex-valued double sideband (DSB) signals, but it requires a high carrier-to-signal power ratio (CSPR) to mitigate the signal-to-signal beat interference (SSBI). Later, a more cost-effective symmetric CADD (S-CADD) has been proposed while the required CSPR is still high. In order to alleviate the high requirements of CSPR, we propose a scheme based on the joint of digital pre-distortion (DPD) at transmitter and clipping at receiver to further improve the S-CADD system performance. This joint processing can not only solve the problem of non-uniform distribution of subcarrier signal-to-noise ratio (SNR) caused by non-ideal transfer function, but also the error propagation problem caused by enhanced SSBI under low CSPR. After the validation of the 64 Gbaud 16-ary quadrature amplitude modulation (16-QAM) orthogonal frequency division multiplexing (OFDM) signal transmitted over 80 km standard single mode fiber (SSMF), the CSPR required by the proposed scheme to reach the 20% soft decision-forward error correction (SD-FEC) and 7% hard decision-forward error correction (HD-FEC) can be reduced by 1.3 dB and 2.8 dB, respectively, with a comparison of the conventional S-CADD. The results show the potential of the proposed scheme in the short-reach optical transmissions.

3.
Opt Lett ; 49(9): 2501-2504, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691754

RESUMO

The multi-eigenvalue multiplexing-based discrete spectrum-modulated nonlinear frequency-division multiplexing (DS-NFDM) system with higher-order modulation format has been demonstrated experimentally. After designing the coefficients of the eigenvalue set and the constellation point distribution of 16-amplitude phase shift keying (16-APSK), the realizations of 14-, 30-, and 46-eigenvalue multiplexed DS-NFDM signals have been implemented. The results show that 46-eigenvalue and 30-eigenvalue multiplexed DS-NFDM signals can transmit 50 km and 400 km over a nonzero dispersion-shifted fiber (NZDSF) under soft-decision forward error correction (SD-FEC) threshold of 2.4E-2, respectively. This demonstration shows for the first time, to the best of our knowledge, the record for multiplexed eigenvalue number and data rate of the multiple-eigenvalue-based DS-NFDM system.

4.
Opt Lett ; 49(11): 3218-3221, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824367

RESUMO

We propose a high-speed multimode fiber short-reach optical interconnect system based on a Kramers-Kronig (KK) field reconstruction with the mode division multiplexing (MDM) and polarization division multiplexing (PDM) technology. In this work, the LP01, LP21a, LP21b, and LP02 modes are selected as independent channels to carry information. The demonstration achieved the 800 Gb/s net data rate per wavelength with a bit-rate-distance-product (BDP) of 8 Tb/s·km. To the best of our knowledge, this is the highest experimental record of a single wavelength BDP over the SMMF with KK detection. In addition, we discuss the system performance after all multiple-input multiple-output (MIMO) and partial MIMO processing and give guidance on the trade-off between system performance and computational resource.

5.
Macromol Rapid Commun ; 45(9): e2300652, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38407457

RESUMO

Pyrrole-based polymers (PBPs), a type of fascinating functional polymers, play a crucial role in materials science. However, efficient synthetic strategies of PBPs with diverse structures are mainly focused on conjugated polypyrroles and still remain challenging. Herein, an atom and step economy protocol is described to access various 2,4-disubstituted PBPs by in situ formation of pyrrole core structure via copper-catalyzed [3+2] polycycloaddition of dialkynones and diisocyanoacetates. A series of PBPs is prepared with high molecular weight (Mw up to 18 200 Da) and moderate to good yield (up to 87%), which possesses a fluorescent emission located in the green to yellow light region. Blending the PBPs with polyvinyl alcohol, the stretchable composite films exhibit a significant strengthening of the mechanical properties (tensile stress up to 59 MPa, elongation at break >400%) and an unprecedented stress-responsive luminescence enhancement that over fourfold fluorescent emission intensity is maintained upon stretching up to 100%. On the basis of computational studies, the unique photophysical and mechanical properties are attributed to the substitution of carbonyl chromophores on the pyrrole unit.


Assuntos
Cobre , Polímeros , Pirróis , Pirróis/química , Cobre/química , Catálise , Polímeros/química , Polímeros/síntese química , Estrutura Molecular , Reação de Cicloadição
6.
Phys Chem Chem Phys ; 26(15): 12070-12083, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38586982

RESUMO

Development and fabrication of a novel gas sensor with superb performance are crucial for enabling real-time monitoring of ethylene (C2H4) and formaldehyde (H2CO) emissions from industrial manufacture. Herein, first-principles calculations and AIMD simulations were carried out to investigate the effect of the Fe-M dimer on the adsorption of C2H4 and H2CO on metal dimer phthalocyanine (FeMPc, M = Ti-Zn) monolayers, and the electronic structures and sensing properties of the above adsorption systems were systematically discussed. The results show that the FeMPc (M = Ti, V, Cr, Mn) monolayers interact with C2H4 and H2CO by chemisorption except for the FeMnPc/H2CO system, while the other adsorption systems are all characterized by physisorption. Interestingly, the adsorption strength of C2H4 and H2CO can be effectively regulated by the bimetallic synergy of the Fe-M dimer. Moreover, the FeCrPc and FeMnPc monolayers exhibit excellent sensitivity towards C2H4 and H2CO, and have short recovery time (4.69 ms-2.31 s) for these gases at room temperature due to the effective surface diffusion at 300 K. Consequently, the FeCrPc and FeMnPc materials can be utilized as high-performance, reusable gas sensors for detecting C2H4 and H2CO, and have promising applications in monitoring the release of ethylene and formaldehyde from industrial processes.

7.
Nano Lett ; 23(23): 10703-10709, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37846923

RESUMO

Ion transport in nanoconfined electrolytes exhibits nonlinear effects caused by large driving forces and pronounced boundary effects. An improved understanding of these impacts is urgently needed to guide the design of key components of the electrochemical energy systems. Herein, we employ a nonlinear Poisson-Nernst-Planck theory to describe ion transport in nanoconfined electrolytes coupled with two sets of boundary conditions to mimic different cell configurations in experiments. A peculiar nonmonotonic charging behavior is discovered when the electrolyte is placed between a blocking electrode and an electrolyte reservoir, while normal monotonic behaviors are seen when the electrolyte is placed between two blocking electrodes. We reveal that impedance shapes depend on the definition of surface charge and the electrode potential. Particularly, an additional arc can emerge in the intermediate-frequency range at potentials away from the potential of zero charge. The obtained insights are instrumental to experimental characterization of ion transport in nanoconfined electrolytes.

8.
Angew Chem Int Ed Engl ; 63(24): e202401388, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38589725

RESUMO

The development of site-selective functionalization of N-heteroarenes is highly desirable in streamlined synthesis. In this context, direct amination of pyridines stands as an important synthetic methodology, with particular emphasis on accessing 4-aminopyridines, a versatile pharmacophore in medicinal chemistry. Herein, we report a reaction manifold for the C4-selective amination of pyridines by employing nucleophilic substitution of hydrogen (SNH). Through 4-pyridyl pyridinium salt intermediates, 4-aminopyridine products are obtained in reaction with aqueous ammonia without intermediate isolation. The notable regioselectivity was achieved by the electronic tuning of the external pyridine reagents along with the maximization of polarizability in the proton elimination stage. Further mechanistic investigations provided a guiding principle for the selective C-H pyridination of additional N-heteroarenes, presenting a strategic avenue for installation of diverse functional groups.

9.
J Am Chem Soc ; 145(29): 16238-16248, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37462685

RESUMO

Controlling regio- and enantioselectivity in C-H functionalization reactions is of paramount importance due to their versatile synthetic utilities. Herein, we describe a new approach for the asymmetric δ-C(sp3)-H amidation catalysis of dioxazolones using a Cu(I) precursor with a chiral bisoxazoline ligand to access six-membered lactams with high to excellent regio- and enantioselectivity (up to >19:1 rr and >99:1 er). Combined experimental and computational mechanistic studies unveiled that the open-shell character of the postulated Cu-nitrenoids enables the regioselective hydrogen atom abstraction and subsequent enantio-determining radical rebound of the resulting carbon radical intermediates. The synthetic utility of this asymmetric cyclization was demonstrated in the diastereoselective introduction of additional functional groups into the chiral δ-lactam skeleton as well as in the rapid access to biorelevant azacyclic compounds.

10.
Cancer Immunol Immunother ; 72(6): 1835-1851, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36688997

RESUMO

Radioresistance and immunosuppression remain the major obstacles in the anti-cancer treatments. This work studies the functions of sialic acid binding Ig like lectin 9 (SIGLEC9) and its related molecules in radioresistance and immunosuppression in esophageal squamous cell carcinoma (ESCC). The single-cell analysis showed that SIGLEC9 was mainly expressed on tumor-associated macrophages (TAMs). Monocytes-derived macrophages were co-cultured with ESCC cells and subjected to radiotherapy. High or low doses of radiotherapy induced SIGLEC9 upregulation and M2 polarization of TAMs. Artificial inhibition of SIGLEC9 in TAMs suppressed the radioresistance and immunosuppressive tumor microenvironment (TME) in the co-cultured ESCC cells. Upstream molecules of SIGLEC9 were predicted via bioinformatics. LINC01004 recruited Spi-1 proto-oncogene (SPI1) in nucleus of TAMs to induce transcriptional activation of SIGLEC9. SIGLEC9 interacted with mucin 1 (MUC1). MUC1 overexpression in ESCCs induced M2 skewing of TAMs, enhanced radioresistance and immunosuppression, and promoted nuclear translocation of ß-catenin to suppress radiotherapy-induced ferroptosis of ESCC cells. These effects were blocked upon SIGLEC9 suppression. In vitro results were reproduced in the animal models with xenograft tumors. Taken together, this study demonstrates that the LINC01004-SPI1 axis-activated SIGLEC9 in TAMs induces radioresistance and the formation of immunosuppressive TME in ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Animais , Humanos , Antígenos CD , Linhagem Celular Tumoral , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/radioterapia , Carcinoma de Células Escamosas do Esôfago/patologia , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Microambiente Tumoral , Macrófagos Associados a Tumor/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
11.
J Transl Med ; 21(1): 472, 2023 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-37455316

RESUMO

BACKGROUND: Cell pyroptosis has a strong proinflammatory effect, but it is unclear whether pyroptosis of liver macrophages exacerbates liver tissue damage during liver ischemia‒reperfusion (I/R) injury. Maresin1 (MaR1) has a strong anti-inflammatory effect, and whether it can suppress liver macrophage pyroptosis needs further study. METHODS: This study aimed to investigate whether MaR1 can alleviate liver I/R injury by inhibiting macrophage pyroptosis. The effects of MaR1 on cell pyroptosis and mitochondrial damage were studied by dividing cells into control, hypoxia/reoxygenation, and hypoxia/reoxygenation + MaR1 groups. Knocking out RORa was used to study the mechanism by which MaR1 exert its protective effects. Transcriptome analysis, qRT‒PCR and Western blotting were used to analyze gene expression. Untargeted metabolomics techniques were used to analyze metabolite profiles in mice. Flow cytometry was used to assess cell death and mitochondrial damage. RESULTS: We first found that MaR1 significantly reduced liver I/R injury. We observed that MaR1 decreased liver I/R injury by inhibiting liver macrophage pyroptosis. Then, we discovered that MaR1 promotes mitochondrial oxidative phosphorylation, increases the synthesis of ATP, reduces the generation of ROS, decreases the impairment of mitochondrial membrane potential and inhibits the opening of mitochondrial membrane permeability transition pores. MaR1 inhibits liver macrophage pyroptosis by protecting mitochondria. Finally, we found that MaR1 exerts mitochondrial protective effects through activation of its nuclear receptor RORa and the PI3K/AKT signaling pathway. CONCLUSIONS: During liver I/R injury, MaR1 can reduce liver macrophage pyroptosis by reducing mitochondrial damage, thereby reducing liver damage.


Assuntos
Hepatopatias , Traumatismo por Reperfusão , Camundongos , Animais , Piroptose , Fosfatidilinositol 3-Quinases/metabolismo , Fígado/metabolismo , Traumatismo por Reperfusão/metabolismo , Macrófagos/metabolismo , Isquemia
12.
Opt Lett ; 48(12): 3259-3262, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319076

RESUMO

Mode-group-division multiplexing (MGDM)-based intensity modulation direct detection (IM/DD) transmission is an attractive approach to increase the capacity for short-reach optical communication. In this Letter, a simple but versatile scheme of mode group (MG) filtering for MGDM IM/DD transmission is proposed. The scheme is applicable to any mode basis in the fiber, and it satisfies the needs of low complexity, low power consumption, and high system performance. By employing the proposed MG filter scheme, a total raw bit rate of a 152-Gb/s multiple-input-multiple-output (MIMO)-free IM/DD co-channel simultaneous transmit and receive system based on two orbital angular momentum (OAM) MGs, each carrying a 38-GBaud four-level pulse amplitude modulation (PAM-4) signal, is experimentally demonstrated over a 5-km few-mode fiber (FMF). The bit error ratios (BERs) of the two MGs are below the 7% hard-decision forward error correction (HD-FEC) BER threshold at 3.8×10-3, using simple feedforward equalization (FFE). Furthermore, the dependability and robustness of such MGDM links are of great significance. Thus, the dynamic evaluation of BER and signal-to-noise ratio (SNR) for each MG is tested over 210 minutes under different conditions. In the dynamic cases, all the BER results using the proposed scheme can be below 1×10-3, which further confirms the stability and feasibility of our proposed MGDM transmission scheme.


Assuntos
Frequência Cardíaca , Movimento (Física) , Razão Sinal-Ruído
13.
Cerebrovasc Dis ; 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38154454

RESUMO

OBJECTIVE: This study aimed to investigate whether Functional Electrical Stimulation (FES) and Transcranial Direct Current Stimulation (tDCS) enhanced the effect of Occupational Therapy (OT) on post-stroke limb functional recovery and quality of life, using direct and network meta-analysis. METHODS: A computerized search was conducted in databases such as Medline, Web of Science, Embase, CNKI (China National Knowledge Infrastructure), Wanfang Data, and VIP Information for prospective randomized controlled trials on OT, FES, and tDCS for improving post-stroke limb motor function and quality of life, with the search cutoff date of July 1, 2023. RESULTS: Following the screening process, a total of 8 research articles were incorporated, encompassing 358 participants. Among these, 177 individuals underwent OT exclusively, while 181 individuals underwent a combined regimen of OT alongside electromagnetic therapy. In terms of the intervention methods, the control group received OT treatment only, while the experimental group employed tDCS in 5 studies and FES in 3 studies. Within these investigations, Fugl-Meyer Assessment (FMA) scores were reported in 8 studies. The aggregated mean difference (MD) for FMA scores was 5.08 (95% CI: 2.46, 7.71), with a specific MD of 2.77 (95% CI: 1.46, 4.09) for the tDCS subgroup and 9.04 (95% CI: 5.34, 12.73) for the FES subgroup. Notably, FES combined with OT exhibited significant advantages in enhancing FMA scores when compared to the combination of tDCS and OT. Furthermore, four studies provided data on modified Barthel Index (MBI) scores, yielding a collective MD of 7.20 (95% CI: 4.44, 9.95). CONCLUSION: In patients with stroke, both FES combined with OT and tDCS combined with OT exhibit substantial enhancements in limb function and quality of life compared to OT alone. Notably, FES combined with OT yields superior clinical benefits when compared to the amalgamation of tDCS and OT.

14.
Environ Sci Technol ; 57(23): 8650-8659, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37235871

RESUMO

Hydrofluoroolefins (HFOs) are being used as substitutes for potent greenhouse gas hydrofluorocarbons (HFCs). However, the use and environmental impacts of HFOs are of great concern due to the rapid degradation of HFOs to produce persistent and phytotoxic trifluoroacetic acid (TFA). Here, we provide a comprehensive projection of HFO emissions in China during 2024-2060 for the first time. Under the Kigali Amendment to the Montreal Protocol, China's HFO emissions are estimated to increase from 1.7 (1.3-2.3) to 148.8 (111.4-185.4) kt in 2024-2060 with cumulative emissions of 2.8 (2.0-3.5) Gt, and cumulative reduced HFCs emissions are evaluated to be 5.4 Gt CO2-equivalent. High HFO emissions would be distributed mainly in the North China Plain and the eastern and coastal areas. HFO-1234yf (2,3,3,3-tetrafluoropropene) contributes most of HFO emissions with a cumulative emission of 1.7 Gt in 2024-2060, while the cumulative increment of TFA deposition from HFO-1234yf emissions would reach 0.4-1.0 Gt. The long-term national-gridded HFO emission inventories can provide scientific support for evaluating the environmental risks of HFOs and developing HFC phase-out pathways for addressing climate change.


Assuntos
Fluorocarbonos , Hidrocarbonetos Fluorados , Ruanda , Fluorocarbonos/análise , Mudança Climática
15.
Eur Neurol ; 86(2): 107-115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36724752

RESUMO

INTRODUCTION: Brain arteriovenous malformations (BAVMs) are high-flow intracranial vascular malformations characterized by the direct connection of arteries to veins without an intervening capillary bed. They are one of the main causes of intracranial hemorrhage and epilepsy, although morbidity is low. Angiogenesis, heredity, inflammation, and arteriovenous malformation syndromes play important roles in BAVM formation. Animal experiments and previous studies have confirmed that NOTCH4 may be associated with BAVM development. Our study identifies a connection between NOTCH4 gene polymorphisms and BAVM in a Chinese Han population. METHODS: We enrolled 150 patients with BAVMs confirmed by digital subtraction angiography (DSA) in the Department of Neurosurgery, Zhujiang Hospital, Southern Medical University from June 2017 to July 2019. Simultaneously, 150 patients without cerebrovascular disease were confirmed by computed tomography angiography/magnetic resonance angiography/DSA. DNA was extracted from peripheral blood and NOTCH4 genotypes were identified by PCR-ligase detection reaction. The χ2 test or Fisher's exact test was used to evaluate the differences in allele and genotype frequencies between the BAVM group, control group, bleeding group, and other complications. RESULTS: Two single-nucleotide polymorphisms (SNPs), rs443198 and rs438475, were significantly associated with BAVM. No SNP genotypes were significantly associated with hemorrhage or epilepsy. SNPs rs443198_AA-SNP and rs438475_AA-SNP may be associated with a lower risk of BAVM (p = 0.011, odds ratio (OR) = 0.459, 95% confidence interval (CI): 0.250-0.845; p = 0.033, OR = 0.759, 95% CI: 0.479-1.204). CONCLUSION: NOTCH4 gene polymorphisms were associated with BAVM and may be a risk factor in a Chinese Han population.


Assuntos
Epilepsia , Malformações Arteriovenosas Intracranianas , Humanos , Polimorfismo de Nucleotídeo Único , População do Leste Asiático , Encéfalo/patologia , Malformações Arteriovenosas Intracranianas/cirurgia , Receptor Notch4/genética
16.
Chaos ; 33(1): 013108, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36725659

RESUMO

Gas-liquid two-phase flow is polymorphic and unstable, and characterizing its flow behavior is a major challenge in the study of multiphase flow. We first conduct dynamic experiments on gas-liquid two-phase flow in a vertical tube and obtain multi-channel signals using a self-designed four-sector distributed conductivity sensor. In order to characterize the evolution of gas-liquid two-phase flow, we transform the obtained signals using the adaptive optimal kernel time-frequency representation and build a complex network based on the time-frequency energy distribution. As quantitative indicators, global clustering coefficients of the complex network at various sparsity levels are computed to analyze the dynamic behavior of various flow structures. The results demonstrate that the proposed approach enables effective analysis of multi-channel measurement information for revealing the evolutionary mechanisms of gas-liquid two-phase flow. Furthermore, for the purpose of flow structure recognition, we propose a temporal-spatio convolutional neural network and achieve a classification accuracy of 95.83%.

17.
Int J Mol Sci ; 24(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36674780

RESUMO

Low temperature is an important limiting factor in the environment that affects the distribution, growth and development of warm-season grasses. Transcriptome sequencing has been widely used to mine candidate genes under low-temperature stress and other abiotic stresses. However, the molecular mechanism of centipedegrass in response to low-temperature stress was rarely reported. To understand the molecular mechanism of centipedegrass in response to low-temperature stress, we measured physiological indicators and sequenced the transcriptome of centipedegrass under different stress durations. Under cold stress, the SS content and APX activity of centipedegrass increased while the SOD activity decreased; the CAT activity, POD activity and flavonoid content first increased and then decreased; and the GSH-Px activity first decreased and then increased. Using full-length transcriptome and second-generation sequencing, we obtained 38.76 G subreads. These reads were integrated into 177,178 isoforms, and 885 differentially expressed transcripts were obtained. The expression of AUX_IAA and WRKY transcription factors and HSF transcription-influencing factors increased during cold stress. Through KEGG enrichment analysis, we determined that arginine and proline metabolism, plant circadian rhythm, plant hormone signal transduction and the flavonoid biosynthesis pathways played important roles in the cold stress resistance of centipedegrass. In addition, by using weighted gene coexpression network analysis (WGCNA), we determined that the turquoise module was significantly correlated with SS content and APX activity, while the blue module was significantly negatively correlated with POD and CAT activity. This paper is the first to report the response of centipedegrass to cold stress at the transcriptome level. Our results help to clarify the molecular mechanisms underlying the cold tolerance of warm-season grasses.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Resposta ao Choque Frio/genética , Poaceae/genética , Poaceae/metabolismo , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas , Temperatura Baixa
18.
J Environ Manage ; 347: 119107, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37801947

RESUMO

Spent selective catalytic reduction (SCR) catalysts are environmentally hazardous and resource-enriching. In this work, V, W, and As in a spent SCR catalyst was extracted by alkali pressure leaching. Results showed that the V, W, and As were loaded on the anatase TiO2 crystal grains as amorphous oxides. The optimum pressure leaching conditions were NaOH concentration of 20 wt%, reaction temperature of 180 °C, reaction time of 120 min, L/S of 10 mL/g, and stirring speed of 300 rpm. The leaching efficiency of W, V, and As reached 98.83%, 100%, and 100%, respectively. The experiment revealed the preferential leaching of V and As rather than W, and the leaching mechanisms of V, W, and As were studied through experiment and density functional theory (DFT). The leaching kinetics of W conformed to a variant of the shrinking core model and the leaching process of W is controlled by both chemical reactions and diffusion processes. During the leaching process, Na2Ti2O4(OH)2 product powder layer was generated, which affects the mass transfer of W. The destruction of the TiO2 skeleton in the spent SCR catalyst is essential for adequate W extraction, especially for the extraction of W embedded in the TiO2 lattice. The DFT simulation result indicated that the V and As loaded onto the TiO2 support are easier to absorb hydroxide ions rather than W, and the leaching reaction energy of V and As was lower than W, As, and V has leaching priority over the leaching of W. Furthermore, an anatase TiO2 photocatalyst with the {001} crystal surface exposed was successfully prepared from the alkali pressure leaching residue. This work provides theoretical support for the metal leaching and utilization of spent SCR catalysts via alkali pressure leaching.


Assuntos
Álcalis , Titânio , Álcalis/química , Titânio/química , Metais , Óxidos/química , Catálise
19.
Pak J Med Sci ; 39(6): 1774-1778, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936771

RESUMO

Objective: To investigate the analgesic effect of thoracic paravertebral block (TPVB) in patients undergoing thoracoscopic lobectomy under general anesthesia (GA). Methods: Clinical records of 82 patients who underwent thoracoscopic lobectomy under GA from October 2021 to October 2022 in the General Hospital of Southern Theater Command were retrospectively analyzed. The patients were divided into two groups according to the method of anesthesia used: general anesthesia group (Group-G, n=37), and TPVB plus GA group (Group-T, n=45). The analgesic effect, mean arterial pressure (MAP), heart rate (HR) and the rate of adverse events in both groups were compared. Results: Visual analogue scale (VAS) scores of patients in Group-T at 12h, 24h and 48h after the operation were significantly lower compared to Group-G (P<0.05). MAP and HR the time of tracheal intubation induction (T1), single lung ventilation (T2), skin incision (T3), operation completion (T4), and 20 minutes after the extubation (T5) were lower in both groups compared to T0, and were significantly higher in Group-T compared to Group-G (P<0.05). The rate of adverse events in Group-T was 6.67%, significantly lower compared to Group-G (24.32%) (P<0.05). Conclusions: TPVB combined with GA can improve the analgesic effect, improve MAP and HR during the operation, and reduce the incidence of adverse events in patients undergoing thoracoscopic lobectomy.

20.
J Am Chem Soc ; 144(7): 2885-2892, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138104

RESUMO

Synthesis of heteroaryl amines has been an important topic in organic chemistry because of their importance in small-molecule discovery. In particular, 2-aminopyrimidines represent a highly privileged structural motif that is prevalent in bioactive molecules, but a general strategy to introduce the pyrimidine C2-N bonds via direct functionalization is elusive. Here we describe a synthetic platform for site-selective C-H functionalization that affords pyrimidinyl iminium salt intermediates, which then can be transformed into various amine products in situ. Mechanism-based reagent design allowed for the C2-selective amination of pyrimidines, opening the new scope of site-selective heteroaryl C-H functionalization. Our method is compatible with a broad range of pyrimidines with sensitive functional groups and can access complex aminopyrimidines with high selectivity.

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