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1.
Front Surg ; 11: 1395271, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38983588

RESUMEN

Objective: Retrospective analysis and comparison of the effects of Enhanced Recovery After Surgery (ERAS) protocol for patients having left and right colectomy surgeries. Method: Out of the patients admitted to Chengdu Shang Jin Nan Fu Hospital and West China Hospital from December 2019 to December 2022, a total of 498 who met the inclusion criteria were selected, 255 with right colectomy(RC) and 243 with left colectomy (LC). Under the conditions of strict compliance with ERAS protocol, the relevant physical indexes of RC and LC, including postoperative rehabilitation (especially median post-operative stay) and complications (especially prolonged postoperative ileus, PPOI), were statistically analyzed and compared. Results: In terms of intraoperative variables, fluid doses were higher in the LC group than in the RC group (P < 0.05), and there was no significant difference between them in terms of operative time, blood loss, need for open surgery, peritoneal contamination, epidural catheter placement, or opioid use (P > 0.05). Compared with the RC group, the LC group had a higher intake of oral liquid at the second postoperative day (POD), and faster first flatulence (P < 0.05). 30 (11.76%) RC patients required nasogastric tube insertion, while only 3 (1.23%) patients in the LC group required the same (P < 0.05). Prolonged postoperative ileus (PPOI) occurred in 48 (18.82%) and 29 (11.93%) patients in the RC and LC groups, respectively (P < 0.05). No significant differences in terms of postoperative complications or length of hospital stay (LoS). stay were observed. Conclusion: As the location of colon cancer changes, the effectiveness of ERAS also varies. More personalized and precise ERAS protocols can reduce the incidence of postoperative complications and promote rapid recovery after surgery.

2.
Angew Chem Int Ed Engl ; 63(7): e202318214, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38100520

RESUMEN

The elements hydrogen, carbon, and nitrogen are among the most abundant in the solar system. Still, little is known about the ternary compounds these elements can form under the high-pressure and high-temperature conditions found in the outer planets' interiors. These materials are also of significant research interest since they are predicted to feature many desirable properties such as high thermal conductivity and hardness due to strong covalent bonding networks. In this study, the high-pressure high-temperature reaction behavior of malononitrile H2 C(CN)2 , dicyandiamide (H2 N)2 C=NCN, and melamine (C3 N3 )(NH2 )3 was investigated in laser-heated diamond anvil cells. Two previously unknown compounds, namely α-C(NH)2 and ß-C(NH)2 , have been synthesized and found to have fully sp3 -hybridized carbon atoms. α-C(NH)2 crystallizes in a distorted ß-cristobalite structure, while ß-C(NH)2 is built from previously unknown imide-bridged 2,4,6,8,9,10-hexaazaadamantane units, which form two independent interpenetrating diamond-like networks. Their stability domains and compressibility were studied, for which supporting density functional theory calculations were performed.

3.
ACS Appl Mater Interfaces ; 15(50): 58497-58507, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38055796

RESUMEN

The shuttle effect and slow conversion kinetics of soluble polysulfides hinder the commercial application of lithium-sulfur batteries (LSBs). In this context, we propose a three-dimensional lamellar-stacked nanostructure of nickel cobalt sulfide (D-NiCo2S4) enriched with lattice defects by manipulating the cations in spinel sulfides. It has an obvious synergistic promotion mechanism for the adsorption and catalysis of lithium sulfides. Specifically, Ni3+ on tetrahedral (Td) sites with strong Ni-S covalency anchors LiPSs, whereas Co3+ on octahedral (Oh) sites promotes a highly efficient catalytic conversion of LiPSs, which is confirmed by experimental results and density functional theory (DFT) calculations. Besides, the crystal defects and distortions in the lamellar region could expose more active sites and enhance the redox reaction kinetics of polysulfides. Hence, Li-S batteries with D-NiCo2S4@S as the cathode show outstanding cycle stability; upon cycling at 1 A/g, the battery achieves a high initial specific capacity of 1001.12 and 655.31 mAh g-1 after 1000 cycles (decay rate as low as 0.05% per cycle), as well as a high initial areal capacity of 3.15 mAh cm-2 under high S loading (4.2 mg cm-2). This work provides a viable scheme for designing efficient bimetal sulfide catalysts and furnishes a rational strategy for constructing LSB cathodes with high specific capacity and high area capacity.

4.
Water Res ; 247: 120777, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37897994

RESUMEN

Four kinds of iron-based materials, i.e., iron-modified attapulgite, calcite, bentonite and dolomite (abbreviated as Fe-ATP, Fe-CA, Fe-BT and Fe-DOL, respectively) were prepared and used to immobilize the phosphorus in the system of overlying water (O-water) and sediment under the feed input condition, and their immobilization efficiencies and mechanisms were investigated. The influence of application mode on the immobilization of phosphorus in the water-sediment system by Fe-ATP, Fe-CA, Fe-BT and Fe-DOL was researched. The effects of Fe-ATP, Fe-CA, Fe-BT and Fe-DOL on the concentration of labile iron in the water-sediment system and the microbial communities in sediment were also studied. The results showed that the Fe-ATP, Fe-CA, Fe-BT and Fe-DOL addition all can effectively immobilize the soluble reactive phosphorus (SRP), dissolved total phosphorus (DTP) and diffusive gradients in thin-films (DGT)-labile phosphorus in O-water under the feed input condition, and also had the ability to inactivate the DGT-labile phosphorus in the top sediment. Although the change in the application mode from the one-time addition to the multiple addition reduced the inactivation efficiencies of SRP and DTP in O-water in the early period of application, it increased the immobilization efficiencies in the later period of application. Although Fe-ATP, Fe-CA, Fe-BT and Fe-DOL had a certain releasing risk of iron into the pore water, they had negligible risk of iron release into O-water. The addition of Fe-ATP, Fe-CA, Fe-BT or Fe-DOL reshaped the sediment bacterial community structure and can affect the microorganism-driven phosphorus cycle in the sediment. Results of this work suggest that Fe-ATP, Fe-CA, Fe-BT and Fe-DOL are promising phosphorus-inactivation materials to immobilize the phosphorus in the water-sediment system under the feed input condition.


Asunto(s)
Microbiota , Contaminantes Químicos del Agua , Agua/química , Contaminantes Químicos del Agua/química , Bentonita/química , Fósforo/química , Hierro/química , Sedimentos Geológicos/química , Carbonato de Calcio , Adenosina Trifosfato , Lagos/química
5.
Chem Commun (Camb) ; 59(54): 8404-8407, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37326427

RESUMEN

Nickel-doped iridium echinus-like nanosheets (NiIr-ENS) have a superior acidic oxygen evolution reaction (OER) activity with a TOF of 1.72 s-1 at an overpotential of 300 mV, 8.6-fold higher than that of IrO2.

6.
J Colloid Interface Sci ; 648: 846-854, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37327627

RESUMEN

Lithium-sulfur (Li-S) battery has been considered as a potential next-era energy storage device. However, its practical application is limited by the volume change of sulfur and the shuttle effect of lithium polysulfides. To effectively overcome these issues, a hollow carbon decorated with cobalt nanoparticles and interconnected by nitrogen doped carbon nanotubes (Co-NCNT@HC) is developed for high-performance Li-S battery. The uniformly distributed nitrogen and cobalt nanoparticles in Co-NCNT@HC are able to enhance the chemical adsorption capability and fasten the transformation speed of the intermediates, thus effectively inhibit the loss of lithium polysulfides. Moreover, the hollow carbon spheres interconnected by carbon nanotubes are structurally stable and electrically conductive. Due to the unique structure, the Li-S battery enhanced by Co-NCNT@HC shows a high initial capacity of 1550 mAh/g at 0.1 A g-1. Even at a high current density of 2.0 A g-1, after 1000 cycles, it still maintains a capacity of 750 mAh/g with a capacity retention of 76.4% (the capacity decay rate is only 0.037% per cycle). This study provides a promising strategy for the development of high-performance Li-S batteries.

7.
Behav Sci (Basel) ; 13(5)2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37232608

RESUMEN

BACKGROUND: During the COVID-19 pandemic, depressive symptoms, a common emotional problem among adolescents, have become more prominent. Regarding the influencing factors of adolescent depressive symptoms, it is widely accepted that parents' problematic cellphone use around the family (specifically parental phubbing) is a strong predictive factor for the development of depressive symptoms among adolescents. Notably, the COVID-19 pandemic caused a sharp increase in the number of individuals with depressive symptoms, and the negative consequences of parental phubbing and depressive symptoms might have been exacerbated. Accordingly, this study aimed to examine the association between parental phubbing and adolescent depressive symptoms as well as their underlying mechanism. METHOD: To test our hypotheses, we conducted an offline/online survey with 614 adolescents in Central China from May to June 2022, which corresponded to a period of strict lockdowns in some areas due to the outbreak of the Omicron variant. The participants completed a set of measures, including a technology interference questionnaire, a parent-child relationship scale, a self-concept clarity scale, and the depressive symptoms scale. RESULTS: Parental phubbing was positively associated with adolescent depressive symptoms; the parent-child relationship and self-concept clarity could independently mediate this relationship; and the parent-child relationship and self-concept clarity were also serial mediators in this association. These findings extend previous research by highlighting the impact of parental technology use on their children and the underlying mechanism explaining adolescent depressive symptoms. They provide practical recommendations for parents to prioritize fostering a positive family environment and minimizing phubbing behaviors to enhance adolescent development, particularly in the context of the COVID-19 pandemic.

8.
Adv Sci (Weinh) ; 10(2): e2205443, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36394092

RESUMEN

The volume change of the silicon anode seriously affects the electrode integrity and cycle stability. Herein, a binder, GCA13, with energy dissipation function and surface stability effect is proposed to enhance the cycle life and specific capacity. Unlike traditional binders that protect silicon electrodes through long-chain networks, GCA13 introduces citric acid molecules with short-range functions on the long-chain guar gum through weak interconnection. This short-range action is similar to the function of a spring, which can effectively buffer the silicon particle pulverization caused by the volume change. Therefore, the electrode can effectively maintain structural integration with ignorable cracks and alleviated thickness swelling. Thus, the Si@GCA13 anode exhibits a high reversible capacity of 1184 mAh g-1 under 2 A g-1 after 740 cycles with a latter coulombic efficiency of 99.9%. Extraordinarily, benefiting from the superior properties of the GCA13 binder, the electrode shows remarkable cycling stability under low (-15 and 0 °C) and high temperatures (60 °C). The work demonstrates the great potential of this binder design strategy to achieve the overall property promotion of Si anodes for practical application even under harsh service conditions.

9.
Artículo en Inglés | MEDLINE | ID: mdl-36554792

RESUMEN

Video game addiction, a common behavioral problem among college students, has been more prominent during the COVID-19 pandemic; at the same time, females' video game usage has also attracted considerable research attention. Against this background and under the perspective of social interaction, this study aimed to examine the relationship between relational victimization and video game addiction among female college students, as well as its underlying mechanism-the mediating roles of social anxiety and parasocial relationships with virtual characters. Female college students (N = 437) were recruited to complete a set of questionnaires voluntarily in June 2022. Through the mediating effect analysis, the results found that (1) relational victimization was positively associated with female college students' video game addiction; (2) social anxiety and parasocial relationships with virtual characters could independently mediate this relation; (3) social anxiety and parasocial relationships with virtual characters were also the serial mediators in this association. These findings not only expand previous studies by revealing the social motivation of video game usage and the underlying mechanism accounting for video game addiction, but also provide basis and guidance for the prevention and intervention of video game addiction in the current context of the COVID-19 pandemic.


Asunto(s)
COVID-19 , Víctimas de Crimen , Humanos , Femenino , Pandemias , COVID-19/epidemiología , Estudiantes , Adicción a la Tecnología , Ansiedad/epidemiología
10.
Shanghai Kou Qiang Yi Xue ; 31(3): 255-259, 2022 Jun.
Artículo en Chino | MEDLINE | ID: mdl-36204952

RESUMEN

PURPOSE: To investigate the effect of Osthole (OST) on lipopolysaccharide (LPS)-induced macrophage polarization and inflammatory reaction. METHODS: The effect of different concentrations of OST on proliferative activity of RAW264.7 macrophages was examined by CCK-8 method; the effect of OST at different concentrations (6.25, 12.5 and 25 µmol/L) on macrophage polarization and inflammation was investigated by using intracellular reactive oxygen species (ROS) detection kit (DCFH-DA), immunofluorescence staining, q-PCR and flow cytometry. The effects of OST on macrophage polarization and inflammatory responses were investigated by immunoblotting of proteins. Graphpad prism 8.0 software package was used for statistical analysis of the data. RESULTS: CCK-8 results showed that OST was not significantly cytotoxic to RAW264.7 at less than 25 µmol/L, immunofluorescence and q-PCR results showed that OST at 6.25, 12.5 and 25 µmol/L inhibited the expression of inflammatory factors in M1 macrophages, and iNOS, TNF-α, CCR7 were reduced in a concentration-dependent manner, and effectively upregulated the expression of M2 inflammatory factors IL-10, Arg-1 and CD206. Flow cytometry showed that OST effectively inhibited the expression of LPS-induced M1 marker CD86 in macrophages. CONCLUSIONS: OST can regulate lipopolysaccharide-induced M1 macrophages polarization and reduce inflammatory reaction.


Asunto(s)
Lipopolisacáridos , Factor de Necrosis Tumoral alfa , Cumarinas , Humanos , Inflamación/inducido químicamente , Interleucina-10 , Lipopolisacáridos/metabolismo , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/farmacología , Receptores CCR7/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
11.
Curr Psychol ; : 1-10, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35935745

RESUMEN

Nowadays, depression has been a prominent mental health problem throughout the world. A common but negative social experience, social exclusion (also known as ostracism) is a great risk factor for individuals' health and adaptation. Undergraduate students are in a development period of challenges and transitions, so they are vulnerable to suffering from depression and negative social experiences. Against this background, the present study aimed to examine the association between social exclusion and undergraduate students' depression as well as the underlying mechanism - the mediating roles of rejection sensitivity and social self-efficacy. Seven hundred sixty-two undergraduate students were recruited to participate in this study, who were asked to complete a set of questionnaires measuring social exclusion, depression, rejection sensitivity, and social self-efficacy. After controlling for gender, social exclusion was positively associated with undergraduate students' depression. And rejection sensitivity and social self-efficacy could significantly mediate this relation through three mediating paths - the separate mediating effects of rejection sensitivity and social self-efficacy, as well as the serial mediating effect of rejection sensitivity and social self-efficacy. These results could not only deepen our understanding of this theme, but also have several practical implications for the intervention of depression, for example, relevant social skill training and cognitive therapy could be adopted to intervene the rejection sensitivity and social self-efficacy.

12.
J Phys Condens Matter ; 34(44)2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-35985306

RESUMEN

Cluster is the intermediate of individual atom and larger agglomeration. The structural evolutions of clusters are critically important to explore the physical properties of bulk solids. Here, we carry out systematic structure predictions of medium-sized vanadium-doped boron clusters by using crystal structure analysis by particle swarm optimization method combined with density function theory calculations. A great deal of low-lying isomers with attractive geometries are discovered, such as the crown-like VB18-cluster and the drum-like VB20-cluster. Interestingly, the VB12-cluster possesses excellently relative stability due to its higher second-order difference and larger highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gap. The molecular orbitals (MOs) and adaptive natural density partitioning (AdNDP) analysis indicate that the 3dorbitals of V atom and the 2pand 2sorbitals of B atoms are the primary constituents of the MOs, and the interactions between V and B atoms are the main factor for the robust stabilization of the anionic VB12-cluster. The present findings advance the understanding of the structural evolution of transition metal doped boron clusters and offer crucial insights for future experiments.

13.
RSC Adv ; 12(30): 19561-19570, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35865605

RESUMEN

Epitope imprinting is an effective way to create artificial receptors for protein recognition. Surface imprinting with immobilized templates and sacrificial supports can generate high-quality imprinted cavities of homogeneous orientation and good accessibility, but it is still challenging to fabricate nanoscale imprinted materials by this approach. Herein, we propose a method for the controlled synthesis of open-mouthed epitope-imprinted polymer nanocapsules (OM-MIP NCs) by limiting the imprinting polymerization on the template-bearing side of the Janus nanoparticles (JNPs). Concurrent bromoacetyl (Ac-Br) and 2-bromoisobutyryl (iB-Br) functionalization of the major portion of SiO2 nanoparticles is achieved via the molten-wax-in-water Pickering emulsion approach. The cysteinyl-derived epitope templates are immobilized through the Ac-Br groups, and then surface imprinting is fulfilled via ATRP initiated by the iB-Br groups. The SiO2 supports are partially etched and then PEGlated, affording OM-MIP NCs with a PEGylated nanocore. The inside nanocore can facilitate collection of the NCs by centrifugation, and its PEGylation can inhibit non-specific binding. The surface imprinting can be optimized through the ATRP time, and the etching can be tailored via the concentration of NH4HF2 employed. For proof-of-concept, with a C-terminus nonapeptide of bovine serum albumin (BSA) chosen as a model epitope and polymerizable carbon dots added to the pre-polymerization solution, fluorescent OM-MIP NCs were fabricated for BSA sensing. The as-synthesized NCs exhibited satisfactory detection performance, with an imprinting factor of 6.1, a limit of detection of 38.1 nM, a linear range of 0.25-6 µM, and recoveries of 98.0 to 104.0% in bovine serum samples.

14.
Behav Sci (Basel) ; 12(5)2022 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-35621454

RESUMEN

This study aimed to examine the association between Machiavellianism and gift-giving in live video streaming, as well as the mediating role of desire for control and the moderating role of materialism in this relation. A sample of 212 undergraduate students (146 males; the average age was 19.80 ± 2.05 years old) with experience of gift-giving in live video streaming was recruited to complete questionnaires on Machiavellianism, desire for control, materialism, and the frequency of gift-giving in live video streaming. The results showed that Machiavellianism was positively associated with gift-giving in live video streaming through the mediating role of desire for control; and the mediating effect of desire for control was moderated by materialism, with this relation being stronger for individuals with a higher level of materialism. Though with several limitations (e.g., cross-sectional method), this study could deepen our understanding of the influencing mechanism of gift-giving in live video streaming, which could also provide practical implications for the sustainable development of the live video streaming industry.

15.
Talanta ; 238(Pt 2): 123070, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34808565

RESUMEN

Molecularly imprinted polymers endowed with photo-luminescent properties have attracted wide research interest in many fields such as biological analysis and diseases diagnosis. Herein, we illustrate a versatile method for the construction of surface protein-imprinted nanoparticles based on metal coordination and anchored carbon dots (CDs) for enhanced fluorescence detection of the target protein. As the fluorescent nanosupports for surface imprinting, CDs-attached SiO2 nanoparticles were synthesized via thiol-ene click chemistry. With histidine (His)-exposed protein as templates, imprinted nanoshells were formed over the nanosupports via copolymerization of a Cu2+-chelating monomer and an oligo (ethylene glycol) monomer, hence producing high-quality imprinted cavities because of both the relatively strong coordination and inhibited non-specific binding. Using lysozyme as a model His-exposed template, the imprinted nanoparticles showed fluorescence enhancement while binding the target protein, and exhibited significantly increased specific fluorescence response than the controls without the metal coordination. They achieved a high imprinting factor of 5.8 and a low limit of detection of 10.1 nM. Furthermore, such sensors were applied to determine lysozyme in diluted chicken egg-white samples with satisfactory recoveries at three spiking levels ranging from 97.9 to 101.4%. Human serum albumin was also used as another template protein for preliminary confirming the generality of the presented strategy.


Asunto(s)
Impresión Molecular , Nanocáscaras , Puntos Cuánticos , Carbono , Humanos , Proteínas de la Membrana , Dióxido de Silicio
16.
Talanta ; 234: 122690, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34364488

RESUMEN

Epitope imprinting has proved to be an effective way for fabricating artificial receptors for protein recognition. Surface imprinting over sacrificial supports is particularly favorable for generating high-quality epitope-imprinted cavities, but obtaining nanomaterials by this way is still a challenge. Herein, we propose a method for the synthesis of oriented surface epitope-imprinted open-mouthed polymer nanocapsules (OM-MIP NCs) by sacrificing asymmetric template-modified Janus nanocores. Amine/aldehyde functionalized SiO2 Janus nanoparticles were prepared via the molten-wax-in-water Pickering emulsion approach, an easy scale-up technique. Epitope templates and vinyl groups were coupled to the aldehyde-bearing major side, whereas polyethylene glycol (PEG) chains were grafted to the amine-modified side. Incomplete imprinted shells were then generated principally on the non-PEGylated side via aqueous precipitation polymerization, hence affording OM-MIP NCs after etching the SiO2 nanocores. With a C-terminus nonapeptide of bovine serum albumin (BSA) chosen as a model epitope and polymerizable carbon dots added to the pre-polymerization solution, fluorescent OM-MIP NCs were synthesized for sensing of BSA. Such NCs reached maximal fluorescent response within 15 min, greatly faster than the closed imprinted NCs within 130 min, proving good accessibility of their inner-surface imprinted cavities thanks to the open mouths. Furthermore, they showed excellent target protein detection performance, with an imprinting factor of 7.8, a limit of detection of 43.8 nM and a linear range of 0.2-6 µM. The recoveries in bovine serum samples at four spiking levels ranged from 99.2 to 107.2%, with relative standard deviations of 1.2-5.9%.


Asunto(s)
Impresión Molecular , Nanocápsulas , Animales , Bovinos , Epítopos , Polímeros , Albúmina Sérica Bovina , Dióxido de Silicio
17.
J Phys Chem A ; 125(19): 4126-4132, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33961432

RESUMEN

Since the discovery of metal-doped boron clusters attracted great significance to create a new class of materials, research interests have been directed to chemical bonding and structural evolution of lanthanide boride clusters. Here, we perform an extensive ground-state structure search for the CeBn and CeBn- clusters in the size range from 9 to 18 using the Crystal structure AnaLYsis by Particle Swarm Optimization method and density functional theory optimization. It is found that the ground-state structures in both neutral and anionic series possess half-sandwich geometry. The host boron moiety in neutral series has a tendency to form borophene-like geometry. The pentagonal and hexagonal holes are more common in the larger anionic CeBn- series. The theoretical photoelectron spectroscopy has been simulated by applying time-dependent density functional theory calculations. The neutral CeB14 cluster is identified as a magic cluster on the basis of its robust relative stability with respect to its neighbors. Electronic structure and chemical bonding analyses reveal that the CeB14 cluster possesses a large HOMO-LUMO gap and enhanced stability with strong delocalized π and δ bonding via interactions between the Ce 5d- and B 2p-AOs.

18.
Cardiovasc Ther ; 2019: 8563717, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31772619

RESUMEN

BACKGROUND: Fibrinogen levels have been associated with coronary plaque vulnerability in experimental studies. However, it has yet to be determined if serum fibrinogen levels are independently associated with coronary plaque vulnerability as detected by optical coherence tomography (OCT) in patients with coronary heart disease. METHODS: Patients with coronary heart disease (CHD) who underwent coronary angiography and OCT in our department from January 2015 to August 2018 were included in this study. Coronary lesions were categorized as ruptured plaque, nonruptured with thin-cap fibroatheroma (TCFA), and nonruptured and non-TCFA. Presence of ruptured plaque and nonruptured with TCFA was considered to be vulnerable lesions. Determinants of coronary vulnerability were evaluated by multivariable logistic regression analyses. RESULTS: A total of 154 patients were included in this study; 17 patients had ruptured plaques, 15 had nonruptured plaques with TCFA, and 122 had nonruptured plaques with non-TCFA. Results of univariate analyses showed that being male, diabetes, current smoking, high body mass index (BMI), and clinical diagnosis of acute coronary syndrome (ACS) were associated with coronary vulnerability. No significant differences were detected in patient characteristics, coronary angiographic findings, and OCT results between patients with higher and normal fibrinogen. Results of multivariate logistic analyses showed that diabetes and ACS were associated with TCFA, while diabetes, higher BMI, and ACS were associated with plaque rupture. CONCLUSIONS: Diabetes, higher BMI, and ACS are independently associated with coronary vulnerability as detected by OCT. Serum fibrinogen was not associated with coronary vulnerability in our cohort.


Asunto(s)
Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Fibrinógeno/análisis , Placa Aterosclerótica , Tomografía de Coherencia Óptica , Síndrome Coronario Agudo/sangre , Síndrome Coronario Agudo/diagnóstico por imagen , Adulto , Anciano , Biomarcadores/sangre , Índice de Masa Corporal , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/patología , Vasos Coronarios/patología , Diabetes Mellitus/sangre , Diabetes Mellitus/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Rotura Espontánea
19.
Phys Chem Chem Phys ; 21(39): 21746-21752, 2019 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-31552405

RESUMEN

A theoretical study of geometrical structures and electronic properties of niobium-doped boron clusters is performed using the CALYPSO approach for the global minimum search followed by density functional theory calculations. It is found that the global minima obtained for the neutral clusters correspond to the half-sandwich structures at n = 10-17 and the tubular-type structures at n = 18-20. The geometrical patterns in the anion series are more complex. The geometries undergo a transformation from the wheel-like structure of NbB10- to the half-sandwich ones beginning at n = 11 and finally to the drum-shaped structures at n ≥ 18. A fascinating NbB12- cluster is uncovered by our structural search, which shows robust stability and can be considered as a new member of the half-sandwich transition metal doped boron clusters. The chemical bond analysis indicates that the high stability is due to the strong interactions between the Nb atom and the B12 host as well as to the strong B-B covalent bonds. Our study will enrich the database of geometrical structures of transition metal doped boron clusters and will stimulate future synthesis of boron-based nanomaterials.

20.
J Phys Condens Matter ; 31(48): 485302, 2019 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-31412328

RESUMEN

Doping of boron-based materials with transition metal atoms allows one to tune or modify the properties and structure of the materials. In this work, an extensive search for the global minima on potential energy surfaces of ScB n and ScB[Formula: see text] clusters has been performed using the CALYPSO method. The structural evolution of scandium doped boron clusters of this range is found to proceed in three steps; namely, the formation of half-sandwich type structures is followed by the formation of drum-like structures with the Sc atom located at the center and terminates with the cage-like structures. It is also found that highly symmetrical geometric structures are more common for the smaller size range of [Formula: see text]. The neutral ScB13 cluster is identified as magic on the basis of an analysis of relative stabilities in the ScB n series. Our analysis of chemical bonding has shown that the stability of this cluster is mainly due to the formation of several delocalized [Formula: see text]-bonding molecular orbitals composed of Sc 3d and B 2s atomic orbitals. These bonds appear to be responsible for the enhanced stability of ScB13 with respect to other Sc-doped boron clusters.

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