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1.
Nature ; 624(7992): 557-563, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37913815

RESUMO

Perovskite solar cells with the formula FA1-xCsxPbI3, where FA is formamidinium, provide an attractive option for integrating high efficiency, durable stability and compatibility with scaled-up fabrication. Despite the incorporation of Cs cations, which could potentially enable a perfect perovskite lattice1,2, the compositional inhomogeneity caused by A-site cation segregation is likely to be detrimental to the photovoltaic performance of the solar cells3,4. Here we visualized the out-of-plane compositional inhomogeneity along the vertical direction across perovskite films and identified the underlying reasons for the inhomogeneity and its potential impact for devices. We devised a strategy using 1-(phenylsulfonyl)pyrrole to homogenize the distribution of cation composition in perovskite films. The resultant p-i-n devices yielded a certified steady-state photon-to-electron conversion efficiency of 25.2% and durable stability.

2.
Proc Natl Acad Sci U S A ; 121(29): e2400898121, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38980900

RESUMO

Precise electrochemical synthesis of commodity chemicals and fuels from CO2 building blocks provides a promising route to close the anthropogenic carbon cycle, in which renewable but intermittent electricity could be stored within the greenhouse gas molecules. Here, we report state-of-the-art CO2-to-HCOOH valorization performance over a multiscale optimized Cu-Bi cathodic architecture, delivering a formate Faradaic efficiency exceeding 95% within an aqueous electrolyzer, a C-basis HCOOH purity above 99.8% within a solid-state electrolyzer operated at 100 mA cm-2 for 200 h and an energy efficiency of 39.2%, as well as a tunable aqueous HCOOH concentration ranging from 2.7 to 92.1 wt%. Via a combined two-dimensional reaction phase diagram and finite element analysis, we highlight the role of local geometries of Cu and Bi in branching the adsorption strength for key intermediates like *COOH and *OCHO for CO2 reduction, while the crystal orbital Hamiltonian population analysis rationalizes the vital contribution from moderate binding strength of η2(O,O)-OCHO on Cu-doped Bi surface in promoting HCOOH electrosynthesis. The findings of this study not only shed light on the tuning knobs for precise CO2 valorization, but also provide a different research paradigm for advancing the activity and selectivity optimization in a broad range of electrosynthetic systems.

3.
Chem Rev ; 124(5): 2839-2887, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38427022

RESUMO

The popularity of portable electronic devices and electric vehicles has led to the drastically increasing consumption of lithium-ion batteries recently, raising concerns about the disposal and recycling of spent lithium-ion batteries. However, the recycling rate of lithium-ion batteries worldwide at present is extremely low. Many factors limit the promotion of the battery recycling rate: outdated recycling technology is the most critical one. Existing metallurgy-based recycling methods rely on continuous decomposition and extraction steps with high-temperature roasting/acid leaching processes and many chemical reagents. These methods are tedious with worse economic feasibility, and the recycling products are mostly alloys or salts, which can only be used as precursors. To simplify the process and improve the economic benefits, novel recycling methods are in urgent demand, and direct recycling/regeneration is therefore proposed as a next-generation method. Herein, a comprehensive review of the origin, current status, and prospect of direct recycling methods is provided. We have systematically analyzed current recycling methods and summarized their limitations, pointing out the necessity of developing direct recycling methods. A detailed analysis for discussions of the advantages, limitations, and obstacles is conducted. Guidance for future direct recycling methods toward large-scale industrialization as well as green and efficient recycling systems is also provided.

4.
Proc Natl Acad Sci U S A ; 120(51): e2314264120, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38100418

RESUMO

The separator with high Young's modulus can avoid the danger of large-sized dendrites, but regulating the chemical behavior of lithium (Li) at the separator/anode interface can effectively eliminate the dendrite issue. Herein, a polyimine aerogel (PIA) with accurate nitrogen (N) functional design is used as the functional separator in Li metal batteries to promote uniform Li nucleation and suppress the dendrite growth. Specifically, the imine (N1) and protonated tertiary amine (N2) sites in the molecular structure of the PIA are significantly different in electron cloud density (ECD) distribution. The N1 site with higher ECD and the N2 site with lower ECD tend to attract and repulse Li+ through electrostatic interactions, respectively. This synergy effect of the PIA separator accelerates the interfacial Li+ diffusion on the Li anode to sustain a uniform two-dimensional Li nucleation behavior. Meanwhile, the well-defined nanochannels of the PIA separator show high affinity to electrolyte and bring uniform Li+ flux for Li plating/stripping. Consequently, the dendrites are effectively suppressed by the PIA separator in routine carbonate electrolyte, and the Li metal batteries with the PIA separator exhibit high Coulombic efficiency and stable high-rate cycling. These findings demonstrate that the ingenious marriage of special chemical structure designs and hierarchical pores can enable the separator to affect the interfacial Li nucleation behavior.

5.
Nano Lett ; 24(12): 3694-3701, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38411584

RESUMO

A functional coating layer (FCL) is widely applied in fast-charging lithium-ion batteries to improve the sluggish Li+ transport kinetics of traditional graphite anodes. However, blindly increasing the Li+ conductivity for FCL reduces the overall electron conductivity of the anodes. Herein, we decoupled the effect of La-doping on TiNb2O7 (TNO) in terms of the phase evolution, Li+/electron transport, and lithiation behavior, and then proposed a promising La0.1TNO FCL with balanced Li+/electron transport for a fast-charging graphite anode. By optimizing the doping concentration of La, more holes are introduced into the TNO as electron carriers without causing lattice distortion, thus maintaining the fast Li+ diffusion channel in TNO. As a result, the graphite with La0.1TNO FCL delivers an excellent capacity of 220.2 mAh g-1 (96.3% retention) after 450 cycles at 3 C, nearly twice that of the unmodified one.

6.
Small ; : e2402197, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38682612

RESUMO

The conjugation of terminal ammonium salt groups with perovskite surfaces is a frequently employed technique that aims to enhance the overall performance of perovskite materials, encompassing both bulk and surface properties. Particularly, it exhibits heightened efficacy when applied to surface modification, due to its ability to mitigate defect accumulation and facilitate facile binding with the receptive sites inherent to the perovskite structure. However, the interaction of the bulk ammonium group with PbI2 has the potential to form a low-dimensional phase of perovskite, which may obstruct carrier extraction at the interface. Therefore, the surface passivators (MeO-PFACl) are designed through intramolecular potential manipulation. The combinations of the electron-donating methoxy group and π-π conjugation of the phenyl ring reduce the local potential at the reactive site of formamidinium group, making it less likely to form a low-dimension phase with perovskite. This surface passivation strategy effectively suppresses the surface nonradiative recombination and promotes the interface carrier extraction. The devices treated with MeO-PFACl have demonstrated exceptional performance, achieving a peak power conversion efficiency (PCE) of 25.88%, with an average PCE of 25.37%. These works offer a novel principle for enhancing both the efficiency and stability of PSCs using ammonium-incorporated molecules without the induction of an additional phase layer.

7.
Brain Behav Immun ; 119: 84-95, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38552922

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that severely affects individuals' daily life and social development. Unfortunately, there are currently no effective treatments for ASD. Dexmedetomidine (DEX) is a selective agonist of α2 adrenergic receptor (α2AR) and is widely used as a first-line medication for sedation and hypnosis in clinical practice. In recent years, there have been reports suggesting its potential positive effects on improving emotional and cognitive functions. However, whether dexmedetomidine has therapeutic effects on the core symptoms of ASD, namely social deficits and repetitive behaviors, remains to be investigated. In the present study, we employed various behavioral tests to assess the phenotypes of animals, including the three-chamber, self-grooming, marble burying, open field, and elevated plus maze. Additionally, electrophysiological recordings, western blotting, qPCR were mainly used to investigate and validate the potential mechanisms underlying the role of dexmedetomidine. We found that intraperitoneal injection of dexmedetomidine in ASD model mice-BTBR T+ Itpr3tf/J (BTBR) mice could adaptively improve their social deficits. Further, we observed a significant reduction in c-Fos positive signals and interleukin-6 (IL-6) expression level in the prelimbic cortex (PrL) of the BTBR mice treated with dexmedetomidine. Enhancing or inhibiting the action of IL-6 directly affects the social behavior of BTBR mice. Mechanistically, we have found that NF-κB p65 is a key pathway regulating IL-6 expression in the PrL region. In addition, we have confirmed that the α2AR acts as a receptor switch mediating the beneficial effects of dexmedetomidine in improving social deficits. This study provides the first evidence of the beneficial effects of dexmedetomidine on core symptoms of ASD and offers a theoretical basis and potential therapeutic approach for the clinical treatment of ASD.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2 , Transtorno do Espectro Autista , Dexmedetomidina , Modelos Animais de Doenças , Interleucina-6 , NF-kappa B , Receptores Adrenérgicos alfa 2 , Comportamento Social , Animais , Dexmedetomidina/farmacologia , Camundongos , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno do Espectro Autista/metabolismo , Masculino , Receptores Adrenérgicos alfa 2/metabolismo , Receptores Adrenérgicos alfa 2/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , NF-kappa B/metabolismo , Interleucina-6/metabolismo , Transdução de Sinais/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Comportamento Animal/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/tratamento farmacológico
8.
Chemphyschem ; 25(13): e202400239, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38578164

RESUMO

Currently, lithium sulfur (Li-S) battery with high theoretical energy density has attracted great research interest. However, the diffusion and loss process of intermediate lithium polysulfide during charge-discharge hindered the application of the Li-S battery in modern life. To overcome this issue, metal organic frameworks (MOFs) and their composites have been regarded as effective additions to restrain the LiPS diffusion process for Li-S battery. Benefiting from the unique structure with rich active sites to adsorb LiPS and accelerate the LiPS redox, the Li-S batteries with MOFs modified exhibit superior electrochemical performance. Considering the rapid development of MOFs in Li-S battery, this review summarizes the recent studies of MOFs and their composites as the sulfur host materials, functional interlayer, separator coating layer, and separator/solid electrolyte for Li-S batteries in detail. In addition, the promising design strategies of functional MOF materials are proposed to improve the electrochemical performance of Li-S battery.

9.
Langmuir ; 40(27): 13984-13994, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38913777

RESUMO

Strong metal-support interaction (SMSI), which has drawn widespread attention in heterogeneous catalysis, is thought to significantly affect the catalytic performance for volatile organic chemical (VOC) abatement. In the present study, strong interactions between platinum and ceria are constructed by modulating the oxygen vacancy concentration of CeO2 through a NaBH4 reduction method. For a catalyst with higher content of oxygen vacancy, more electrons would transfer from ceria to Pt, which is attributed to the stronger effect of SMSI. The obtained electron-richer Pt sites exhibit higher ability for toluene activation, contributing to better performance for toluene oxidation. On the other hand, the stronger metal-support interaction would facilitate CeOx species migrating to the Pt nanoparticle surface and forming an encapsulated structure. Smaller Pt dispersion leads to fewer sites for toluene adsorption and activation, which is to the disadvantage of the reaction. Therefore, taking the negative and positive effects together, the Pt/CeO2-0.5 catalyst has the highest catalytic performance for toluene abatement. Our study provides new insights into strong metal-support interaction on toluene oxidation and contributes to designing noble metal catalysts for VOC abatement.

10.
J Gastroenterol Hepatol ; 39(7): 1256-1266, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38638082

RESUMO

Magnetic compression anastomosis (MCA) is a new method that provides sutureless passage construction for tubular organs. Due to the high recurrence rate of conventional endoscopic treatment and the high morbidity and mortality of surgical procedures, the MCA technique shows promise. The aim of this review is to comprehensively examine the literature related to the use of MCA in different gastrointestinal diseases over the past few years, categorizing them according to the anastomotic site and describing in detail the various methods of magnet delivery and the clinical outcomes of MCA. MCA is an innovative technique, and its use represents an advancement in the field of minimally invasive interventions. Comparison studies have shown that the anastomosis formed by MCA is comparable to or better than surgical sutures in terms of general appearance and histology. Although most of the current research has involved animal studies or studies with small populations, the safety and feasibility of MCA have been preliminarily demonstrated. Large prospective studies involving populations are still needed to guarantee the security of MCA. For technologies that have been initially used in clinical settings, effective measures should also be implemented to identify, even prevent, complications. Furthermore, specific commercial magnets must be created and optimized in this emerging area.


Assuntos
Anastomose Cirúrgica , Imãs , Humanos , Anastomose Cirúrgica/métodos , Endoscopia Gastrointestinal/métodos , Gastroenteropatias/cirurgia , Animais , Magnetismo , Resultado do Tratamento , Procedimentos Cirúrgicos sem Sutura/métodos , Pressão
11.
Nano Lett ; 23(20): 9609-9617, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37843362

RESUMO

Lithium (Li) dendrite growth in a routine carbonate electrolyte (RCE) is the main culprit hindering the practical application of Li metal anodes. Herein, we realize the regulation of the LiPF6 decomposition pathway in RCE containing 1.0 M LiPF6 by introducing a "self-polymerizing" additive, ethyl isothiocyanate (EITC), resulting in a robust LiF-rich solid electrolyte interphase (SEI). The effect of 1 vol % EITC on the electrode/electrolyte interfacial chemistry slows the formation of the byproduct LixPOFy. Such a LiF-rich SEI with EITC polymer winding exhibits a high Young's modulus and a uniform Li-ion flux, which suppresses dendrite growth and interface fluctuation. The EITC-based Li metal cell using a Li4Ti5O12 cathode delivers a capacity retention of 81.4% over 1000 cycles at 10 C, outperforming its counterpart. The cycling stability of 1 Ah pouch cells was further evaluated under EITC. We believe that this work provides a new method for tuning the interfacial chemistry of Li metal through electrolyte additives.

12.
Angew Chem Int Ed Engl ; 63(3): e202316839, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38014862

RESUMO

Reasonably elevating the working voltage (≥4.4 V vs. Li/Li+ ) of the cathode is one of the efficient approaches to maximize the energy density of lithium-ion batteries (LIBs). As a preferred partner for high-voltage LIB systems, localized high-concentration electrolyte (LHCE), characterized by a stronger Li solvation structure, less free solvent, and robust electrode/electrolyte interphase has attracted much attention in academic circles. Herein, we systematically studied the role of the diluent in LHCE on the formation of the cathode electrolyte interphase (CEI) and elucidated that the existing anion-diluent pairing in the inner Helmholtz plane (IHP) results in an uneven CEI and subsequent battery degradation under high voltage. A m-fluorotoluene (mFT) diluent was further employed in the LHCE containing lithium difluoro(oxalato)borate (LiDFOB) to facilitate a uniform and rich-anion-derived CEI, since the weaker interaction of HmFT -BDFOB - , as compared to the HHhydrofluoroether -BDFOB - , reduces the influence of mFT in IHP or initial CEI formation. Consequently, the mFT-dominated LHCE propels the high-voltage performance of LIBs one step forward, endowing a 4.6 V-class 1.2-Ah graphite||LiNi0.8 Co0.1 Mn0.1 O2 pouch cells a 90.4 % capacity retention after 130 cycles. Our study thus describes a new index affecting the CEI formation and proposes novel strategies to deeply optimize the high-voltage LIBs.

13.
J Am Chem Soc ; 145(13): 7288-7300, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36876987

RESUMO

Recycling spent lithium-ion batteries (LIBs) has become an urgent task to address the issues of resource shortage and potential environmental pollution. However, direct recycling of the spent LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode is challenging because the strong electrostatic repulsion from a transition metal octahedron in the lithium layer provided by the rock salt/spinel phase that is formed on the surface of the cycled cathode severely disrupts Li+ transport, which restrains lithium replenishment during regeneration, resulting in the regenerated cathode with inferior capacity and cycling performance. Here, we propose the topotactic transformation of the stable rock salt/spinel phase into Ni0.5Co0.2Mn0.3(OH)2 and then back to the NCM523 cathode. As a result, a topotactic relithiation reaction with low migration barriers occurs with facile Li+ transport in a channel (from one octahedral site to another, passing through a tetrahedral intermediate) with weakened electrostatic repulsion, which greatly improves lithium replenishment during regeneration. In addition, the proposed method can be extended to repair spent NCM523 black mass, spent LiNi0.6Co0.2Mn0.2O2, and spent LiCoO2 cathodes, whose electrochemical performance after regeneration is comparable to that of the commercial pristine cathodes. This work demonstrates a fast topotactic relithiation process during regeneration by modifying Li+ transport channels, providing a unique perspective on the regeneration of spent LIB cathodes.

14.
Small ; 19(20): e2207480, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36840656

RESUMO

Mixed lead-tin (PbSn) perovskite solar cells (PSCs) possess low toxicity and adjustable bandgap for both single-junction and all-perovskite tandem solar cells. However, the performance of mixed PbSn PSCs still lags behind the theoretical efficiency. The uncontrollable crystallization and the resulting structural defect are important reasons. Here, the bidirectional anions gathering strategy (BAG) is reported by using Methylammonium acetate (MAAc) and Methylammonium thiocyanate (MASCN) as perovskite bulk additives, which Ac- escapes from the perovskite film top surface while SCN- gathers at the perovskite film bottom in the crystallization process. After the optoelectronic techniques, the bidirectional anions movement caused by the top-down gradient crystallization is demonstrated. The layer-by-layer crystallization can collect anions in the next layer and gather at the broader, enabling a controllable crystallization process, thus getting a high-quality perovskite film with better phase crystallinity and lower defect concentration. As a result, PSCs treated by the BAG strategy exhibit outstanding photovoltaic and electroluminescent performance with a champion efficiency of 22.14%. Additionally, it demonstrates excellent long-term stability, which retains ≈92.8% of its initial efficiency after 4000 h aging test in the N2 glove box.

15.
Plant Cell ; 32(9): 2823-2841, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32699171

RESUMO

Zeins are the predominant storage proteins in maize (Zea mays) seeds, while Opaque2 (O2) is a master transcription factor for zein-encoding genes. How the activity of O2 is regulated and responds to external signals is yet largely unknown. Here, we show that the E3 ubiquitin ligase ZmRFWD3 interacts with O2 and positively regulates its activity by enhancing its nuclear localization. Ubiquitination of O2 enhances its interaction with maize importin1, the α-subunit of Importin-1 in maize, thus enhancing its nuclear localization ability. We further show that ZmRFWD3 can be phosphorylated by a Suc-responsive protein kinase, ZmSnRK1, which leads to its degradation. We demonstrated that the activity of O2 responds to Suc levels through the ZmSnRK1-ZmRFWD3-O2 signaling axis. Intriguingly, we found that Suc levels, as well as ZmRFWD3 levels and the cytonuclear distribution of O2, exhibit diurnal patterns in developing endosperm, leading to the diurnal transcription of O2-regulated zein genes. Loss of function in ZmRFWD3 disrupts the diurnal patterns of O2 cytonuclear distribution and zein biosynthesis, and consequently changes the C/N ratio in mature seeds. We therefore identify a SnRK1-ZmRFWD3-O2 signaling axis that transduces source-to-sink signals and coordinates C and N assimilation in developing maize seeds.


Assuntos
Nitrogênio/metabolismo , Proteínas de Plantas/metabolismo , Zea mays/metabolismo , Núcleo Celular/metabolismo , Ritmo Circadiano/fisiologia , Endosperma/crescimento & desenvolvimento , Endosperma/metabolismo , Regulação da Expressão Gênica de Plantas , Lisina/metabolismo , Fosforilação , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Estabilidade Proteica , Serina/metabolismo , Transdução de Sinais , Sacarose/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zeína/genética , Zeína/metabolismo
16.
Neurochem Res ; 48(8): 2350-2359, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36947308

RESUMO

Sympathetic axonal sprouting into dorsal root ganglia is a major phenomenon implicated in neuropathic pain, and sympathetic ganglia blockage may relieve some intractable chronic pain in animal pain models and clinical conditions. These suggest that sympathetic ganglia participated in the maintenance of chronic pain. However, the molecular mechanism underlying sympathetic ganglia-mediated chronic pain is not clear. Here, we found that spared nerve injury treatment upregulated the expression of ADAMTS4 and AP-2α protein and mRNA in the noradrenergic neurons of sympathetic ganglia during neuropathic pain maintenance. Knockdown the ADAMTS4 or AP-2α by injecting specific retro scAAV-TH (Tyrosine Hydroxylase)-shRNA ameliorated the mechanical allodynia induced by spared nerve injury on day 21 and 28. Furthermore, chromatin immunoprecipitation and coimmunoprecipitation assays found that spared nerve injury increased the recruitment of AP-2α to the ADAMTS4 gene promoter, the interaction between AP-2α and histone acetyltransferase p300 and the histone H4 acetylation on day 28. Finally, knockdown the AP-2α reduced the acetylation of H4 on the promoter region of ADAMTS4 gene and suppressed the increase of ADAMTS4 expression induced by spared nerve injury. Together, these results suggested that the enhanced interaction between AP-2α and p300 mediated the epigenetic upregulation of ADAMTS4 in sympathetic ganglia noradrenergic neurons, which contributed to the maintenance of spared nerve injury induced neuropathic pain.


Assuntos
Dor Crônica , Neuralgia , Traumatismos do Sistema Nervoso , Ratos , Animais , Regulação para Cima , Dor Crônica/metabolismo , Ratos Sprague-Dawley , Neuralgia/genética , Neuralgia/metabolismo , Gânglios Simpáticos , Gânglios Espinais/metabolismo , Traumatismos do Sistema Nervoso/metabolismo , Epigênese Genética
17.
Langmuir ; 39(44): 15756-15765, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37883782

RESUMO

Owing to the advantages of organic field-effect transistors (OFETs) in the versatility of organic synthesis, multiparameter measurement, and signal amplification, sensors based on OFETs have received increasing attention for detecting volatile organic compounds (VOCs). However, false device operation and gas-sensing measurements often occur to vitiate the advantages of OFETs and even output error gas-sensing signals. In this work, by experimentally and theoretically studying the effects of VOC adsorption on the operational characteristics of the OFET, the proper operations of OFETs in gas-sensing measurements were clarified. The multiparameter measurements of OFETs showed that the source-drain current was the optimized parameter for achieving high responsivity, and other OFET parameters could be used for fingerprint analysis. By operating OFETs in the near-threshold region, the amplification effect was switched to enhance the responsivity by orders of magnitude to VOCs, while in the overthreshold region, the OFETs had a low signal-to-noise ratio. Besides, a counteraction effect and an uncertainty effect were discovered, leading to error gas-sensing signals. A theoretical study was carried out to reveal the dependency of the gas-sensing properties of OFETs on VOC adsorption. A series of rules were proposed for guiding the measurements of OFET sensors by taking full advantage of transistors in gas-sensing applications.

18.
J Org Chem ; 88(3): 1836-1843, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36696583

RESUMO

A new synthesis of functionalized 2H-pyran-2-ones has been developed through N-heterocyclic carbene-catalyzed formal [3 + 3] annulation of alkynyl esters with enolizable ketones. The key to the success of this protocol relies on the use of an NHC instead of a tertiary amine as the catalyst. This protocol also features a broad substrate scope and mild metal-free conditions, offering simple and rapid access to the target molecules in a highly regioselective manner.

19.
J Gastroenterol Hepatol ; 38(11): 1892-1899, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37608577

RESUMO

BACKGROUND AND AIM: Neoplastic polyp removal is important for colorectal cancer prevention. Endoscopists have proposed cold snare endoscopic mucosal resection (CS-EMR) as a solution to solve positive cutting edges and postoperative bleeding. However, many controversies regarding its specific performance in practice have been reported. The aim of this pooled analysis was to report the efficacy and safety of CS-EMR. METHODS: PubMed/Medline, Embase, Google Scholar, and the Cochrane Library searched up to January 2022 to identify studies in which CS-EMR was performed for the removal of colorectal polyps measuring less than 20 mm. The primary outcome was the complete resection rate (CRR), and the secondary outcome was the rate of adverse events. RESULTS: Eleven studies were included in the final analysis, which included 861 colorectal polyps. The overall CRR with CS-EMR was 96.3% (95% CI, 93.9-98.2%). The early and delayed bleeding rates of CS-EMR were 3.1% (95% CI, 1.2-5.5%) and 1.4% (95% CI, 0.6-2.4%), respectively. There were no statistical significances between CS-EMR and cold snare polypectomy (CSP) in terms of the CRR and adverse events, as well as CS-EMR and hot snare endoscopic mucosal resection (HS-EMR). CONCLUSIONS: For resecting colorectal polyps measuring ≤20 mm, CS-EMR is an effective attempt. However, compared with CSP and HS-EMR, CS-EMR did not improve the efficiency and safety of polypectomy as expected. Multicenter randomized controlled trials are needed to compare CSP with CS-EMR in the resection of <10 mm polyps and HSP with CS-EMR in the resection of ≥10 mm polyps.


Assuntos
Pólipos do Colo , Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Pólipos do Colo/cirurgia , Pólipos do Colo/etiologia , Colonoscopia/efeitos adversos , Hemorragia Pós-Operatória/etiologia , Hemorragia Pós-Operatória/prevenção & controle , Neoplasias Colorretais/cirurgia , Neoplasias Colorretais/etiologia , Ressecção Endoscópica de Mucosa/efeitos adversos , Estudos Multicêntricos como Assunto
20.
BMC Cardiovasc Disord ; 23(1): 69, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36740681

RESUMO

BACKGROUND: Inflammatory factors are well-established indicators for vascular disease, but the D-dimer to lymphocyte count ratio (DLR) is not measured in routine clinical care. Screening of DLR in individuals may identify individuals at in-hopital mortality of acute aortic dissection (AD). METHODS: A retrospective analysis of clinical data from 2013 to 2020 was conducted to identify which factors were related to in-hospital mortality risk of AD. Baseline clinical features, cardiovascular risk factors, and laboratory parameters were obtained from the hospital database. The end point was in-hospital mortality. Forward conditional logistic regression was performed to identify independent risk factors for AA in-hospital death. The cutoff value of the DLR should be ideally calculated by receiver operating characteristic (ROC) analysis. RESULTS: The in-hospital mortality rate was 15% (48 of 320 patients). Patients with in-hospital mortality had a higher admission mean DLR level than the alive group (1740 vs. 1010, P < .05). The cutoff point of DLR was 907. The in-hospital mortality rate in the high-level DLR group was significantly higher than that in the low-level DLR group (P < .05). Univariate analysis showed that 8 of 38 factors were associated with in-hospital mortality (P < .05), including admission WBC, neutrophils, lymphocytes, neutrophils/lymphocytes (NLR), prothrombin time (PT), heart rate (HR), D-dimer, and DLR. In multivariate analysis, DLR (odds ratio [OR] 2.127, 95% CI 1.034-4.373, P = 0.040), HR (odds ratio [OR] 1.016, 95% CI 1.002-1.030, P = 0.029) and PT (odds ratio [OR] 1.231, 95% CI 1.018-1.189, P = 0.032) were determined to be independent predictors of in-hospital mortality (P < .05). CONCLUSION: Compared with the common clinical parameters PT and HR, serum DLR level on admission is an uncommon but independent parameter that can be used to assess in-hospital mortality in patients with acute AD.


Assuntos
Dissecção Aórtica , Mortalidade Hospitalar , Humanos , Dissecção Aórtica/diagnóstico , Biomarcadores , Contagem de Linfócitos , Linfócitos , Neutrófilos , Prognóstico , Estudos Retrospectivos , Curva ROC
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