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1.
Nature ; 600(7887): 54-58, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34666338

RESUMO

The Moon has a magmatic and thermal history that is distinct from that of the terrestrial planets1. Radioisotope dating of lunar samples suggests that most lunar basaltic magmatism ceased by around 2.9-2.8 billion years ago (Ga)2,3, although younger basalts between 3 Ga and 1 Ga have been suggested by crater-counting chronology, which has large uncertainties owing to the lack of returned samples for calibration4,5. Here we report a precise lead-lead age of 2,030 ± 4 million years ago for basalt clasts returned by the Chang'e-5 mission, and a 238U/204Pb ratio (µ value)6 of about 680 for a source that evolved through two stages of differentiation. This is the youngest crystallization age reported so far for lunar basalts by radiometric dating, extending the duration of lunar volcanism by approximately 800-900 million years. The µ value of the Chang'e-5 basalt mantle source is within the range of low-titanium and high-titanium basalts from Apollo sites (µ value of about 300-1,000), but notably lower than those of potassium, rare-earth elements and phosphorus (KREEP) and high-aluminium basalts7 (µ value of about 2,600-3,700), indicating that the Chang'e-5 basalts were produced by melting of a KREEP-poor source. This age provides a pivotal calibration point for crater-counting chronology in the inner Solar System and provides insight on the volcanic and thermal history of the Moon.

2.
Altern Ther Health Med ; 29(7): 335-339, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37499156

RESUMO

Objective: This study aimed to evaluate the effectiveness of three-dimensional CT bronchial angiography (3D-CTBA) in facilitating precise lung segmental resection. Methods: A total of 80 patients with peripheral lung nodules undergoing anatomical lung segmentectomy were randomly divided into two groups: a control group (n = 40) and a study group (n = 40). The control group received surgical treatment based on chest CT prompts and traditional lung segmentation, while the study group's chest CT imaging data were reconstructed into 3D images before surgery, followed by lung segmentectomy. Surgical parameters and complication rates were compared between the two groups. Results: The study group exhibited significantly shorter operation time, drainage time, and hospitalization time, as well as reduced intraoperative bleeding, lung tissue resection size, and drainage volume, compared to the control group (P < .05). Hospitalization costs did not differ significantly between the two groups (P > .05). The incidence of lung infection, pulmonary atelectasis, and arrhythmia showed no significant difference between the groups (P > .05). However, the study group demonstrated significantly lower rates of hemoptysis and lung leakage compared to the control group (P < .05). There was no significant difference in the composition of postoperative pathological staging between the two groups (χ2 = 0.721, P > .05). Conclusions: The application of 3D-CTBA technology provides clear visualization of the lung's anatomical structure and contributes to enhanced safety and effectiveness in thoracoscopic lung segmental precision resection.


Assuntos
Neoplasias Pulmonares , Pneumonectomia , Humanos , Pneumonectomia/métodos , Pulmão/diagnóstico por imagem , Pulmão/cirurgia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Tomografia Computadorizada por Raios X , Angiografia , Estudos Retrospectivos
3.
Pak J Med Sci ; 39(5): 1451-1455, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37680844

RESUMO

Objective: To compare the effect of percutaneous balloon compression (PBC) and microvascular decompression (MVD) in the treatment of trigeminal neuralgia (TN). Methods: Data of 98 patients with TN, admitted to Chenzhou First People's Hospital from May 2020 to May 2022, were retrospectively collected. Patients were divided into two groups based on the surgical method. A total of 53 patients treated with PBC comprised the PBC-group and 45 patients treated with MVD comprised the MVD-group. The immediate pain relief, long-term efficacy, surgical complications, and masticatory muscle strength of the two groups were compared and analyzed. Results: There was no significant difference in the immediate pain relief and long-term e efficacy, between the two groups (P>0.05). Complication rate in the PBC-group was significantly lower than that in the MVD-group (3.77% vs 17.78%, P<0.05). Medical records within 14 days after the operation showed that the incidence of facial numbness and masticatory muscle weakness in the PBC-group were 37.74% and 28.30% respectively, significantly higher than those in MVD-group (4.44% and 2.22%) (P<0.05). These symptoms gradually improved three months after the surgery, and were almost completely resolved after six months. Conclusions: Compared with MVD, PBC has the same effect in the treatment of TN. PBC is a minimally invasive, safe, and effective method with a low complication rate. Although masticatory muscle strength is slightly impacted by PBC, it gradually recovers within six months after the operation.

4.
Anal Chem ; 94(22): 7944-7951, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35616317

RESUMO

High-quality oxygen isotope analysis of composition-variable minerals (e.g., ubiquitous carbonates) using secondary ion mass spectrometry (SIMS) is extremely challenging. The classical off-line procedure, which requires additional electron probe microanalyzer (EPMA) chemical compositions for calibrating instrumental mass fractionation (IMF), is inherently inaccurate and analytically inefficient. In this study, the first accurate and paired SIMS analysis of δ18O and Fe# [molar Fe/(Mg + Fe)] in dolomite is reported. Based on five newly developed dolomite O-isotopic standards with an Fe# range of 0.01-0.35 obtained by SIMS, a novel accurate and rapid online matrix effect calibration method for dolomite O-isotope analysis was developed using concurrent SIMS 18O-16O-56Fe16O-24Mg16O measurements without additional chemical electron probe microanalysis. A logistic equation was proposed as the best-fit curve to represent the δ18O matrix effect based on the 56Fe16O/24Mg16O ratios. For CTD-4 carbonatitic dolomite with variable Fe# but homogeneous oxygen isotopes, the off-line method exhibited highly variable apparent δ18O values in the range of 5.74-10.11‰. The online method yielded a homogeneous δ18O value of 7.94 ± 0.34‰ (2SD, n = 40), which is comparable with that of bulk analysis (7.94 ± 0.20‰; 2SD). Comprehensive analyses validated the online method as the best strategy for performing accurate δ18O analysis of samples with highly heterogeneous compositions. Based on its accuracy, simplicity, and economic feasibility, this method has potential applications in the analysis of composition-complex dolomites, detrital dolomites, and other precious terrestrial and extraterrestrial materials.


Assuntos
Carbonato de Cálcio , Minerais , Carbonato de Cálcio/química , Calibragem , Magnésio , Isótopos de Oxigênio/química
5.
J Chem Phys ; 156(21): 214304, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35676127

RESUMO

We present a joint experimental and theoretical study of rotationally inelastic collisions between NO (X2Π1/2, ν = 0, j = 1/2, f) radicals and CO (X1Σ+, ν = 0, j = 0) molecules at a collision energy of 220 cm-1. State-to-state scattering images for excitation of NO radicals into various final states were measured with high resolution by combining the Stark deceleration and velocity map imaging techniques. The high image resolution afforded the observation of correlated rotational excitations of NO-CO pairs, which revealed a number of striking scattering phenomena. The so-called "parity-pair" transitions in NO are found to have similar differential cross sections, independent of the concurrent excitation of CO, extending this well-known effect for collisions between NO and rare gas atoms into the realm of bimolecular collisions. Forward scattering is found for collisions that induce a large amount of rotational energy transfer (in either NO, CO, or both), which require low impact parameters to induce sufficient energy transfer. This observation is interpreted in terms of the recently discovered hard collision glory scattering mechanism, which predicts the forward bending of initially backward receding trajectories if the energy uptake in the collision is substantial in relation to the collision energy. The experimental results are in good agreement with the predictions from coupled-channels quantum scattering calculations based on an ab initio NO-CO potential energy surface.

6.
Langmuir ; 37(45): 13187-13193, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34726927

RESUMO

Blue-emitting room-temperature phosphorescence (RTP) materials have always been one of the major challenges in the field of RTP materials. Deep-blue (430 nm) RTP emitting silica microparticles were prepared via a one-step hydrothermal reaction from a single raw material of 3-aminopropyltriethoxysilane (APTES). APTES provided amino groups and ethyl groups as a nitrogen and carbon source, which was further condensed to be nitrogen-contained carbon dots (CDs). Besides, the siloxane side of APTES was hydrolyzed and formed silica microparticles. The CDs with the potential chromophores (C═O and C-N etc.) were connected to SiO2 via Si-C bonds of APTES. The covalent bonds and the rigid silica network effectively restricted the motions of potential chromophores of the CDs and reduced the energy gap between the singlet state and triplet state, which was favorable to the RTP. It was believed that this work will guide researchers to realize other blue or deep-blue RTP materials.

7.
J Chem Phys ; 153(6): 064301, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287454

RESUMO

We present a combined experimental and theoretical study of state-to-state inelastic collisions between NO (X 2Π1/2, j = 1/2, f) radicals and D2 (j = 0, 1, 2, 3) molecules at collision energies of 100 cm-1 and 750 cm-1. Using the combination of Stark deceleration and velocity map imaging, we fully resolve pair-correlated excitations in the scattered molecules. Both spin-orbit conserving and spin-orbit changing transitions in the NO radical are measured, while the coincident rotational excitation (j = 0 → j = 2) and rotational de-excitation (j = 2 → j = 0 and j = 3 → j = 1) in D2 are observed. De-excitation of D2 shows a strong dependence on the spin-orbit excitation of NO. We observe translation-to-rotation energy transfer as well as direct rotation-to-rotation energy transfer at the lowest collision energy probed. The experimental results are in good agreement with cross sections obtained from quantum coupled-channels calculations based on recent NO-D2 potential energy surfaces. The observed trends in the correlated scattering cross sections are understood in terms of the NO-D2 quadrupole-quadrupole interaction.

8.
Meteorit Planet Sci ; 55(11): 2341-2359, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33510569

RESUMO

The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada. Several fragments fell onto frozen surfaces of lakes and, thanks to weather radar data, were recovered days after the fall. The studied rock fragments show no or little signs of terrestrial weathering. Here, we present the initial results from an international consortium study to describe the fall, characterize the meteorite, and probe the collision history of Hamburg. About 1 kg of recovered meteorites was initially reported. Petrology, mineral chemistry, trace element and organic chemistry, and O and Cr isotopic compositions are characteristic of H4 chondrites. Cosmic ray exposure ages based on cosmogenic 3He, 21Ne, and 38Ar are ~12 Ma, and roughly agree with each other. Noble gas data as well as the cosmogenic 10Be concentration point to a small 40-60 cm diameter meteoroid. An 40Ar-39Ar age of 4532 ± 24 Ma indicates no major impact event occurring later in its evolutionary history, consistent with data of other H4 chondrites. Microanalyses of phosphates with LA-ICPMS give an average Pb-Pb age of 4549 ± 36 Ma. This is in good agreement with the average SIMS Pb-Pb phosphate age of 4535.3 ± 9.5 Ma and U-Pb Concordia age of 4535 ± 10 Ma. The weighted average age of 4541.6 ± 9.5 Ma reflects the metamorphic phosphate crystallization age after parent body formation in the early solar system.

9.
Phys Chem Chem Phys ; 20(7): 4917-4925, 2018 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-29384156

RESUMO

The dissociative photoionization of CF3Cl was investigated in the photon energy range of 12.30-18.50 eV. The low-lying electronic states of CF3Cl+ cations were prepared by the method of threshold photoelectron-photoion coincidence (TPEPICO). The threshold photoelectron spectrum and the coincident time-of-flight mass spectra at the specific photon energies were recorded. Only a CF3+ fragment was observed at lower energy, while a CF2Cl+ fragment appeared for C2E and D2E states. As Cl-loss from the ground ionic state is statistical, the total kinetic energy release distribution (KERD) is represented as a Boltzmann profile, and a 0 K appearance energy of AP0 =12.79 ± 0.02 eV is derived from the statistical modelling of the breakdown diagram from 12.60 to 12.85 eV without taking into account the kinetic shift. For the A2A1 and B2A2 states of CF3Cl+ cations, the total KERDs are bimodal, where a parallel faster dissociation appears together with the statistical distribution. At higher energies like the C2E and D2E ionic states, a bimodal distribution similar to that of the A2A1 and B2A2 states is also observed for the KERD. With the aid of the calculated Cl-loss potential energy curves, the dissociative mechanisms of internal energy-selected CF3Cl+ cations are proposed.

10.
Phys Chem Chem Phys ; 20(18): 12444-12453, 2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29697730

RESUMO

We present a combined experimental and theoretical study of state-to-state inelastic scattering of NO(X2Π1/2, j = 1/2f) with O2(X3Σg-) molecules at a collision energy of 480 cm-1, focusing in particular on the observation and interpretation of correlated excitations in both NO and O2. Various final states of the NO radical, in both spin-orbit manifolds, were measured with high resolution using a crossed molecular beam apparatus which employs a combination of Stark deceleration and velocity map imaging. Velocity map imaging directly measures both the angular distribution and the radial velocity distribution of the scattered NO molecules, which probes the kinetic energy uptake or release and hence correlated excitations of NO-O2 pairs. Simultaneous excitations of NO and O2 were resolved for all studied final states of NO. In all cases, the experimental results excellently agree with the results of simulations based on quantum scattering calculations. Trends are discussed by analyzing the scattering wave functions from the calculations.

11.
Urol Int ; 97(2): 125-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27379709

RESUMO

OBJECTIVES: To assess the safety and efficacy of local anesthetic infiltration around nephrostomy tract on postoperative pain control after percutaneous nephrolithotomy. METHODS: This systematic review was performed based on randomized clinic trials about local anesthetic infiltration around nephrostomy tract on postoperative pain control. The weighted mean difference (WMD), with their corresponding 95% CI, was calculated to compare continuous variables. RESULTS: Our results showed that the consumption of analgesic was less in the experimental group than in the control group (WMD -25.32, 95% CI -48.09 to -2.55, p = 0.003). There was no significant difference between the mean Visual Analog Scale (VAS) in the experimental group than the control group after 6 h while significantly lower after 24 h. The time of first analgesic demand was significantly longer in the experimental group (WMD 2.19, 95% CI 0.98-3.41). There was no significant difference between 2 groups in terms of operation time, hemoglobin (Hb) alteration, and hospital stay. CONCLUSION: Local anesthetic infiltration around nephrostomy tract had similar efficacy in the control group in terms of operation time, Hb alteration, and hospital stay, but offers some potential advantages in terms of analgesia requirement, the time of first analgesic demand, and VAS-24 h. However, good quality and large studies with long-term follow-up are warranted for further research.


Assuntos
Anestesia Local , Anestésicos Locais/administração & dosagem , Nefrostomia Percutânea , Dor Pós-Operatória/prevenção & controle , Humanos , Nefrostomia Percutânea/efeitos adversos , Dor Pós-Operatória/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
12.
Cell Immunol ; 295(2): 144-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25880106

RESUMO

Thymic stromal lymphopoietin (TSLP) is an interleukin 7-like cytokine produced mainly by epithelial cells. Many studies indicate that TSLP contributes to promote T helper (Th) 2 immune responses which are associated with the pathogenesis of allergic inflammatory diseases. Base on the cross-talk between Th2 inflammation and cancers, we will highlight the role of TSLP in the progression of cancers in this review. TSLP is involved in the increasing prevalence of Tregs in the cancer microenvironment. Besides, TSLP has an important role in promoting the growth of vascular endothelial cells and angiogenesis, which could further promote the development and progression of cervical cancer. It gives the evidence that TSLP could induce EMT to promote cancer metastasis. In addition, TSLP could be detected in some fibroblasts and may play a role in the pathogenesis of non-allergic diseases characterized by a type 2 immune response and organ fibrosis.


Assuntos
Citocinas/imunologia , Transição Epitelial-Mesenquimal/imunologia , Neoplasias/imunologia , Linfócitos T Reguladores/imunologia , Animais , Humanos , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Neovascularização Patológica/imunologia , Linfopoietina do Estroma do Timo
13.
Int J Biol Macromol ; 271(Pt 1): 132546, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38782330

RESUMO

This study investigated the function of AMP deaminase 1 (AMPD1) in Jingyuan chicken and the biological activity of its expression vector. AMPD1 was cloned and sequenced from chicken breast muscle tissue by RT-PCR and further analyzed using Cluster, DNASTAR, and online bioinformatics software, as well as vector construction, qPCR, Western blotting, enzymatic digestion, and sequencing. The coding sequence was 2162 bp, encoding 683 amino acids and producing a protein of approximately 78.95 kDa. After verification, the overexpression plasmids pEGFP-AMPD1, Cas9/sgRNA2, and Cas9/sgRNA3 were found to have biological activity in chicken muscle cells and individual chickens, and two sgRNAs (sgRNA2, sgRNA3) were identified that could edit AMPD1. The qPCR and Western blotting result showed that the pEGFP-AMPD1 plasmid significantly increased both mRNA and protein expression of AMPD1. T7EI digestion showed editing efficiencies of approximately 35 %, 37 %, and 33 % for sgRNA2, sgRNA3, and sgRNA2 + sgRNA3 of AMPD1 in chicken muscle cells. In comparison, TA cloning sequencing showed editing efficiencies of approximately 36.7 %, 86.7 %, and 26.7 % and editing efficiencies in chicken individuals of approximately 71 %, 45 %, and 76.7 %, respectively. These results provide a theoretical basis and support for further investigation into the function of the AMPD1 gene.


Assuntos
AMP Desaminase , Galinhas , Clonagem Molecular , Vetores Genéticos , Animais , Galinhas/genética , AMP Desaminase/genética , AMP Desaminase/metabolismo , Sequência de Aminoácidos , Expressão Gênica , Edição de Genes/métodos , Plasmídeos/genética , RNA Guia de Sistemas CRISPR-Cas/genética
14.
CNS Neurosci Ther ; 30(4): e14706, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38584347

RESUMO

OBJECTIVE: This study aimed to investigate whether spontaneous brain activity can be used as a prospective indicator to identify cognitive impairment in patients with Parkinson's disease (PD). METHODS: Resting-state functional magnetic resonance imaging (RS-fMRI) was performed on PD patients. The cognitive level of patients was assessed by the Montreal Cognitive Assessment (MoCA) scale. The fractional amplitude of low-frequency fluctuation (fALFF) was applied to measure the strength of spontaneous brain activity. Correlation analysis and between-group comparisons of fMRI data were conducted using Rest 1.8. By overlaying cognitively characterized brain regions and defining regions of interest (ROIs) based on their spatial distribution for subsequent cognitive stratification studies. RESULTS: A total of 58 PD patients were enrolled in this study. They were divided into three groups: normal cognition (NC) group (27 patients, average MoCA was 27.96), mild cognitive impairment (MCI) group (21 patients, average MoCA was 23.52), and severe cognitive impairment (SCI) group (10 patients, average MoCA was 17.3). It is noteworthy to mention that those within the SCI group exhibited the most advanced chronological age, with an average of 74.4 years, whereas the MCI group displayed a higher prevalence of male participants at 85.7%. It was found hippocampal regions were a stable representative brain region of cognition according to the correlation analysis between the fALFF of the whole brain and cognition, and the comparison of fALFF between different cognitive groups. The parahippocampal gyrus was the only region with statistically significant differences in fALFF among the three cognitive groups, and it was also the only brain region to identify MCI from NC, with an AUC of 0.673. The paracentral lobule, postcentral gyrus was the region that identified SCI from NC, with an AUC of 0.941. The midbrain, hippocampus, and parahippocampa gyrus was the region that identified SCI from MCI, with an AUC of 0.926. CONCLUSION: The parahippocampal gyrus was the potential brain region for recognizing cognitive impairment in PD, specifically for identifying MCI. Thus, the fALFF of parahippocampal gyrus is expected to contribute to future study as a multimodal fingerprint for early warning.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Humanos , Masculino , Idoso , Feminino , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/patologia , Estudos Prospectivos , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Imageamento por Ressonância Magnética/métodos , Hipocampo/patologia
15.
Sci Bull (Beijing) ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38724301

RESUMO

A "once-in-a-millennium" super rainstorm battered Zhengzhou, central China, from 07/17/2021 to 07/22/2021 (named "7.20" Zhengzhou rainstorm). It killed 398 people and caused billions of dollars in damage. A pressing question is whether rainstorms of this intensity can be effectively documented by geological archives to understand better their historical variabilities beyond the range of meteorological data. Here, four land snail shells were collected from Zhengzhou, and weekly to daily resolved snail shell δ18O records from June to September of 2021 were obtained by gas-source mass spectrometry and secondary ion mass spectrometry. The daily resolved records show a dramatic negative shift between 06/18/2021 and 09/18/2021, which has been attributed to the "7.20" Zhengzhou rainstorm. Moreover, the measured amplitude of this shift is consistent with the theoretical value estimated from the flux balance model and instrumental data for the "7.20" Zhengzhou rainstorm. Our results suggest that the ultra-high resolution δ18O of land snail shells have the potential to reconstruct local synoptic scale rainstorms quantitatively, and thus fossil snail shells in sedimentary strata can be valuable material for investigating the historical variability of local rainstorms under different climate backgrounds.

16.
Sci Bull (Beijing) ; 69(10): 1486-1494, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38472019

RESUMO

Sulfate reduction is an essential metabolism that maintains biogeochemical cycles in marine and terrestrial ecosystems. Sulfate reducers are exclusively prokaryotic, phylogenetically diverse, and may have evolved early in Earth's history. However, their origin is elusive and unequivocal fossils are lacking. Here we report a new microfossil, Qingjiangonema cambria, from ∼518-million-year-old black shales that yield the Qingjiang biota. Qingjiangonema is a long filamentous form comprising hundreds of cells filled by equimorphic and equidimensional pyrite microcrystals with a light sulfur isotope composition. Multiple lines of evidence indicate Qingjiangonema was a sulfate-reducing bacterium that exhibits similar patterns of cell organization to filamentous forms within the phylum Desulfobacterota, including the sulfate-reducing Desulfonema and sulfide-oxidizing cable bacteria. Phylogenomic analyses confirm separate, independent origins of multicellularity in Desulfonema and in cable bacteria. Molecular clock analyses infer that the Desulfobacterota, which encompass a majority of sulfate-reducing taxa, diverged ∼2.41 billion years ago during the Paleoproterozoic Great Oxygenation Event, while cable bacteria diverged ∼0.56 billion years ago during or immediately after the Neoproterozoic Oxygenation Event. Taken together, we interpret Qingjiangonema as a multicellular sulfate-reducing microfossil and propose that cable bacteria evolved from a multicellular filamentous sulfate-reducing ancestor. We infer that the diversification of the Desulfobacterota and the origin of cable bacteria may have been responses to oxygenation events in Earth's history.


Assuntos
Fósseis , Filogenia , Sulfatos , Sulfatos/metabolismo , Deltaproteobacteria/genética , Deltaproteobacteria/metabolismo , Oxirredução , Planeta Terra , Evolução Biológica , Oxigênio/metabolismo , Sedimentos Geológicos/microbiologia , Sulfetos/metabolismo , China , Ferro
17.
Science ; 379(6636): 1031-1036, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36893253

RESUMO

Collisions between cold polar molecules represent a fascinating research frontier but have proven hard to probe experimentally. We report measurements of inelastic cross sections for collisions between nitric oxide (NO) and deuterated ammonia (ND3) molecules at energies between 0.1 and 580 centimeter-1, with full quantum state resolution. At energies below the ~100-centimeter-1 well depth of the interaction potential, we observed backward glories originating from peculiar U-turn trajectories. At energies below 0.2 centimeter-1, we observed a breakdown of the Langevin capture model, which we interpreted in terms of a suppressed mutual polarization during the collision, effectively switching off the molecular dipole moments. Scattering calculations based on an ab initio NO-ND3 potential energy surface revealed the crucial role of near-degenerate rotational levels with opposite parity in low-energy dipolar collisions.

18.
ACS Omega ; 8(21): 19099-19108, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37273603

RESUMO

Titanium silica (TS-1) membrane catalysts grown on the surfaces of spherical substrates can both exploit the high catalytic performance and facilitate their separation from products after the reaction. In this work, a simple static crystallization method was used to perform the in situ construction of a TS-1 membrane on the surfaces of micron-sized spherical carriers. The shortcomings of the TS-1 membrane under static crystallization conditions were overcome by in situ dynamic crystallization, and the effect of rotation speed on the formation of the molecular sieve membrane was investigated. The results showed that the molecular sieve membrane was smooth and homogeneous, with a higher synthesis efficiency at a slow rotational speed. The micron TS-1 spherical membrane catalytic chloropropene epoxidation reaction was investigated in a fixed bed, and the conversion of hydrogen peroxide and selectivity of epichlorohydrin reached 99.4 and 96.8%, respectively. After being reused twice, the catalyst still maintained a stable catalytic performance.

19.
Clin Cosmet Investig Dermatol ; 15: 2013-2015, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36172246

RESUMO

Facial flushing affects the work and life of patients. The specific pathogenesis and conditions of facial flushing may be complicated. A 47-year-old perimenopausal woman was presented to the Pain Management with a 4-month history of facial flushing. The patient didn't have any history of special illness or history of allergies. Treatments with methylprednisolone, thalidomide, hydroxychloroquine drugs or sympathetic blockages (stellate ganglion block) were unable to effectively improve the symptoms. We believed that the facial flushing might be associated with the anxiety. After two weeks of venlafaxine medication, the symptoms were 90% relieved. We found that venlafaxine effectively improved flushing that may be related to anxiety.

20.
ACS Omega ; 7(16): 13687-13696, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35559160

RESUMO

The development of low-cost and high-performance electrocatalysts for simultaneously boosting the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) is highly crucial but still challenging. Herein, a facile one-step solid-phase polymerization and confined pyrolysis strategy is developed for scalable synthesis of a Fe x P/Fe3C-based (x = 1, 2) heterojunction with controllable iron phosphide crystal phases. By effective heterojunction interface regulation, the strong synergic effect between FeP/Fe3C and N- and P-codoped carbon (NPC) modified the electronic structure, resulting in an excellent electrocatalytic performance for the HER, OER, and ORR synchronously. Typically, the FeP/Fe3C@NPC catalyst exhibits efficient HER activity with a low overpotential of 10 mA cm-2 for the HER (97 mV) and OER (440 mV) and a high half-wave potential of 0.87 V for the ORR, as well as excellent stability in alkaline media. Theoretical calculations demonstrated that Fe3C can promote the activation of water molecules, while FeP is beneficial to the removal of H2 and the FeP/Fe3C heterojunction can facilitate both Volmer and Heyrovsky steps in the HER process simultaneously. Moreover, FeP has a stronger inhibitory effect on OH adsorption, revealing that the FeP/Fe3C heterojunction also shows a better promoting effect for both the OER and ORR, respectively.

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