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1.
Artigo em Inglês | MEDLINE | ID: mdl-38593437

RESUMO

Wide-bandgap (WBG) inverted perovskite solar cells (PSCs) are used as the top cell for tandem solar cells, which is an effective way to outperform the Shockley-Queisser limit. However, the low efficiency and poor phase stability still seriously restrict the application of WBG inverted PSCs. Here, the surface of the WBG perovskite film was passivated by the synthesized 1,2,4-tris(3-thienyl)benzene (THB). The THB size well matches with the halogen ion vacancy on the perovskite surface, and the S atom in THB can strongly interact with Pb2+ on the surface of the WBG perovskite film to the greatest extent, which effectively passivates surface defects and suppresses the recombination of carriers caused by these defects. At the same time, the S atom in THB occupied the migration site of the halogen ions, which inhibits the migration of halogen ions. Due to the strong conjugation effect and stability of THB, it can be locked on the surface of perovskite to increase the lattice strength and inhibit the segregation of photoinduced halide, thus improving the performance and operational stability of PSCs. The THB-modified WBG (Eg = 1.71 eV) PSC achieves a maximum power conversion efficiency of 20.75%, and its 99.0% is retained after 1512 h at a relative humidity of 10-25%. Under the irradiation of 1000 lx LED light, the indoor power conversion efficiency of the THB-modified WBG PSC reaches 34.15%.

2.
Ital J Pediatr ; 49(1): 139, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37840137

RESUMO

BACKGROUND: Maternal diabetes might be related to a high risk of allergic disease in offspring. However, it remains unknown if maternal gestational diabetes mellitus (GDM) is also associated with a high incidence of childhood asthma in offspring. A systematic review and meta-analysis was performed to investigate the above association. METHODS: Relevant observational studies were obtained by search of electronic databases including Medline, Embase, Cochrane Library, and Web of Science. A randomized-effects model was selected to pool the data by incorporating the influence of potential heterogeneity. The Newcastle-Ottawa Scale was used for study quality evaluation. Subgroup analyses were performed to evaluate the potential influences of study characteristics on the outcome. RESULTS: Ten datasets from seven moderate to high quality cohort studies, involving 523,047 mother-child pairs were included in the meta-analysis. Overall, maternal GDM was associated with a higher risk of childhood asthma in offspring (risk ratio [RR]: 1.22, 95% confidence interval [CI]: 1.07 to 1.39, p = 0.003; I2 = 30%). Subgroup analyses showed that the association was not significantly affected by study design, validation methods for GDM, or diagnostic strategy for asthma (p for subgroup analyses all > 0.05). The association between maternal GDM and asthma in offspring was more remarkable after adjusting maternal body mass index in early pregnancy (RR: 1.50 versus 1.06, p < 0.001), but significantly weakened after adjusting hypertensive disorders during pregnancy (RR: 1.08 versus 1.50, p = 0.001). CONCLUSIONS: Maternal GDM may be associated with an increased incidence of childhood asthma in offspring.


Assuntos
Asma , Diabetes Gestacional , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiologia , Estudos de Coortes , Asma/epidemiologia , Asma/etiologia
3.
Cell Mol Biol (Noisy-le-grand) ; 67(5): 248-255, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35818246

RESUMO

The study aimed to investigate the expression of lncRNA-BCYRN1 in serum of pediatric asthma patients and the related factors of disease induction. For this purpose, a total of 95 patients were randomly selected from the outpatient department of pediatrics of a hospital affiliated with the medical university from October 2018 to October 2019, including 25 intermittent episodes, 25 mild persistent episodes, 20 moderate persistent episodes, and 20 severe persistent episodes. In addition, serum samples from 30 healthy control children were selected for comparison. The expression levels of lncRNA-BCYRN1 and the inflammatory factors IL-4, IL-12, IL-37, 25-(OH)D in serum were detected by real-time quantitative fluorescence PCR(qrt-PCR), and the influence of the expression of lncRNA-BCYRN1 on the prognosis of children and its correlation with the expression of TNF-a and IgE were analyzed. Results: the expression of LncRNA BCYRN1 was positively correlated with the expression of TNF-α and IgE (r=0.712, 0.748, all P<0.001). Serum IL-4 levels in each group were 21.06±2.93pg/ml, 23.88±3.91pg/ ml, 25.85±4.02pg/ml, and 17.74±1.77pg/ml, respectively. Serum IL-4 levels in each group were higher than those in the normal control group, and the difference was statistically significant (P<0.001). The levels of IL-12, IL-37 and 25-(OH)D in all the affected groups were decreased compared with the normal control group, while the serum levels of IL-37 were negatively correlated with IL-4 and positively correlated with IL-12 and 25-(OH)D. Conclusion: serum IL-4 level of children in the disease group was increased, indicating hyperexpression of Th2 cell function, and serum IL-12 and IL-37 levels were decreased, suggesting decreased Th1 cell function, indicating Th1/Th2 imbalance in children with asthma. The low serum vitamin D level of children in the disease group was negatively correlated with serum IL-4 level and positively correlated with IL-12 and IL-37 levels, which may be the trigger factor of inflammation in asthmatic diseases and should be supplemented in clinical treatment. The expression level of lncRNA-BCYRN1 is related to the severity of pediatric asthma, which can be used as a prognostic indicator and has a certain effect on the prognosis of clinical pediatric asthma.


Assuntos
Asma , Pediatria , RNA Longo não Codificante , Asma/genética , Criança , Humanos , Imunoglobulina E , Interleucina-12 , Interleucina-4/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
4.
IEEE Trans Cybern ; 52(7): 6591-6602, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34705662

RESUMO

This article concentrates on the synchronization of discrete-time persistent dwell-time (PDT) switched bidirectional associative memory inertial neural networks with time-varying delays. Through the use of the switched system theory related to the PDT, the convex optimization technique together with some straightforward decoupling methods, an appropriate mode-dependent controller with nonfragility is developed to acclimatize itself to some practical circumstances. Simultaneously, sufficient conditions of ensuring the H∞ performance and exponential stability for the resulting switched synchronization error system are derived. Finally, a numerical example is utilized to show the validity of the model constructed and the influence of the PDT on the H∞ performance. In addition, an image encryption example is employed to show the potential application prospect of the investigated system.


Assuntos
Algoritmos , Redes Neurais de Computação , Fatores de Tempo
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 254: 119655, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-33744702

RESUMO

Metal-organic framework (MOFs), also known as porous coordination polymers (PCPs), is a new kind of crystalline porous materials, which has received extensive attention in the past few decades. As a new type of sensing material, MOFs stand out from many other traditional fluorescence sensors because of its crystal characteristics, structural diversity, stable porosity and adjustable functional characteristics. In this work, the bi-functional building block containing aromatic carboxylic acid and triazole moieties, namely 3-(1H-1,3,4-triazol-1-yl) benzoic acid, was selected as the linker to synthesize {[Cd(µ5-L)⋅I}n (1, HL = 3-(1H-1,3,4-triazol-1-yl)benzoic acid) by hydrothermal method with transition CdII metal centers. Firstly, the preliminary characterization of 1 was carried out by means of PXRD, FT-IR, and then the UV and fluorescence tests were conducted to study the fluorescence properties of 1. The crystal structure analysis indicates that CdII is the center and the ligand is bridged to form a two-dimensional porous structure. In addition, 1 has good selectivity for Fe3+ and Cr2O72-, meanwhile, it has high detection sensitivity (Ksv quenching efficiency for Fe3+: 1.2 × 104 M-1 and Cr2O72- 1.85 × 104 M-1) and low detection limit (Fe3+: 19.21 µM and Cr2O72-: 12.46 µM). The results of photoluminescence test show that 1 can detect cations and anions with high sensitivity, resist the interference of other ions, and have good reusability. As far as we know, 1 is the first example of ultra-stable two-dimensional (2D) Cadmium (II) microporous coordination material as a fluorescence sensor for Fe3+ and Cr2O72-.

6.
IEEE Trans Cybern ; 50(6): 2440-2449, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30892266

RESUMO

This paper focuses on the exponential H∞ filtering issue for a class of continuous-time switched neural networks (NNs). Our aim is to design a mode-dependent filter acquiring the state of the investigated system, and ensuring the global uniform exponential stability of the resulting filtering error system. The persistent dwell-time (PDT) switching strategy is employed to represent the switching among NNs. By utilizing a suitable Lyapunov function and the switched system theory, some criteria for the solvability of the addressed problem are presented under the full consideration of switching frequency. Finally, the filter gains are derived by a straightforward decoupling method, and with the aid of the algorithm of the continuous-time PDT switching regularity, the availability of the filter is expounded through a numerical example.


Assuntos
Algoritmos , Redes Neurais de Computação , Simulação por Computador , Fatores de Tempo
7.
RSC Adv ; 8(26): 14705-14712, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-35540736

RESUMO

The coinage atom-inserted cyanide/isocyanide compounds, XMCN and XMNC (X = halogens) formed by the insertion of a coinage atom into the X-C(N) bonds of XCN (or XNC), were investigated by ab initio methods. XMCN was predicted to be more stable than XMNC, which is different from the case of XUCN/XUNC reported previously. Based on the analyses on the ionization dissociation pathways, the M-C (or M-N) bond is more easily broken than the X-M bond. Moreover, the order of the M-C (or M-N) bond energy in XMCN (or XMNC) is XAuCN (XAuNC) > XCuCN (XCuNC) > XAgCN (XAgNC). The shift characters of v C-N in XMCN (or XMNC) with respect to the concerning precursor can be used to identified XMCN and XMNC experimentally. The results of charge decomposition analysis (CDA) and atoms-in-molecule (AIM) illustrate that the X-M and M-C(N) bond behaves as a coordination bond, while the C-N bond is a typical polar covalent bond. The higher thermodynamic stability of XMCN is the result of the -CN group having better coordination ability than the -NC group.

8.
Sci Rep ; 7(1): 10278, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28860526

RESUMO

Although HNgCCX (Ng = Kr and Xe; X = F and Cl) have been identified in cryogenic matrices, similar Br and I analogues have not been prepared so far. In this paper, the nature of HNgCCX (Ng = Kr and Xe; X = F, Cl, Br and I) have been investigated by ab initio methods. The main characteristic absorption peak of HNgCCX is the v H-Ng, which decreases as X varies from F to I. Moreover, the H-Xe bond is stronger than the H-Kr bond. The v C≡C and v C-X exhibit red- and blue-shift characters, respectively, especially the C-X bond is abnormal blue-shift halogen bond. AIM results show that the H-Ng bond is essentially covalent bond and the covalent character of H-Xe bond is underestimated, and the trend of the covalent character is C-Cl > C-Br > C-F > C-I. Although HNgCCX is instable thermodynamically with respect to Ng + HCCX, it is kinetically stable with respect to the two-/three-body channels due to the relatively larger energy barriers. The three-body channels of HNgCCX is the main decomposition channel, and the kinetically stability of HXeCCX is more than its Kr analogues. This study is helpful for the preparation of new HNgCCX in cryogenic matrices.

9.
Inorg Chem ; 55(24): 12559-12567, 2016 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-27989178

RESUMO

Two kinds of halogenated uranium cyanide/isocyanide compounds, XUCN and XUNC (X = halogen) formed by the insertion of uranium atom into X-C(N) bonds of XCN (or XNC), were investigated by DFT and ab initio methods. Although XNC is less stable thermodynamically than XCN, XUNC is more stable than XUCN and is expected to be prepared and characterized in matrix isolation experiments. The C-N stretching vibration mode (νC-N) is the primary fingerprint for the identification of these isomers due to its red-shift character with respect to the relevant precursor. Atoms-in-molecule (AIM) analysis illustrates that both X-U and U-C(N) bonds in XUCN and XUNC show closed-shell interaction character, although partial covalent character contributes to them, and can be denoted as X-U2+(CN)- and X-U2+(NC)-, respectively. Charge decomposition analysis (CDA) further reveals that the isocyanide exhibits better donation performance than the cyanide, which should be the root cause of the difference between XUCN and XUNC.

10.
Palliative Care Research ; : 223-231, 2013.
Artigo em Japonês | WPRIM (Pacífico Ocidental) | ID: wpr-374788

RESUMO

<b>Objective</b>: The reliability and validity of a scale to evaluate the supportive functions of community-based self-help groups (SHGs) for cancer survivors, which was named the Evaluation of Supportive Functions Scale (ESFS) was investigated. Moreover, factors related to the evaluation of supportive functions were identified. <b>Methods</b>: An anonymous, self-administered survey comprised of items related to the background, evaluation of supportive functions of SHGs, and participation status (frequency of participation, satisfaction with participation, and types of activities undertaken) was conducted with members of SHGs for cancer survivors (n=1,350). Valid responses (573 valid responses, 42.4%) were analyzed and ESFS was developed based on the responses. <b>Results</b>: The 21-item ESFS had excellent internal consistency. Factor analyses revealed a 4-factor solution of internally consistent subscales: Learning, Helping each other, Social involvement and Catalyst for personal growth. There was a significant relationship between participants' evaluation of supportive functions of SHGs with gender, role in the SHGs and type of cancer. The subscales were significantly related to the frequency of participation, satisfaction, and the type and range of activities that were undertaken. <b>Conclusions</b>: ESFS can measure participants' recognition of the utility of SHGs. We have discussed the practical applications of the scale as a tool for measuring the effectiveness of SHGs.

11.
Phys Chem Chem Phys ; 14(22): 8083-9, 2012 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-22534779

RESUMO

The noble-gas molecules, HKrOX (with X = F, Cl, Br and I), have been investigated by ab initio calculation. Equilibrium geometry, harmonic and anharmonic vibrational frequencies, energies, partial charges are calculated. All HKrOX molecules studied here are bound equilibrium structures with Cs symmetry. The frequency calculation indicates that the H-Kr stretching mode is anharmonic and is very likely to be observed in the experiments. The two-body decomposition reaction is exothermic and lead to products of Kr as well as HOX, while the three-body decomposition reaction is also exothermic with respect to the neutral decomposition products (H + Kr + OX). Moreover, HKrOX is kinetically stable with respect to the decomposition reactions due to the enough high energy barriers, which indicates the possibility to identify these HKrOX compounds in noble-gas matrices. The bonding in HKrOX is studied by QTAIM analysis and the localized molecular orbital energy decomposition analysis (LMO-EDA) method at the MP2 level of theory with a large basis set. The results show that HKrOX is a typical ionic bond, denoted as (HKr)(+)(OX)(-), and the electrostatic interaction between (HKr)(+) and (OX)(-) makes the main contribution to the ionic bond.

12.
J Mol Model ; 18(7): 3113-23, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22212733

RESUMO

ωB97XD/6-311++G(d,p) calculations were carried out to investigate the hydrogen-bonding interactions between adrenaline (Ad) and water. Six Ad-H(2)O complexes possessing various types of hydrogen bonds (H-bonds) were characterized in terms of their geometries, energies, vibrational frequencies, and electron-density topology. Natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) analyses were performed to elucidate the nature of the hydrogen-bonding interactions in these complexes. The intramolecular H-bond between the amino and carboxyl oxygen atom of Ad was retained in most of the complexes, and cooperativity between the intra- and intermolecular H-bonds was present in some of the complexes. H-bonds in which hydroxyls of Ad/water acted as proton donors were stronger than other H-bonds. Both hydrogen-bonding interactions and structural deformation play important roles in the relative stabilities of the complexes. The intramolecular H-bond was broken during the formation of the most stable complex, which indicates that Ad tends to break the intramolecular H-bond and form two new intermolecular H-bonds with the first water molecule.


Assuntos
Epinefrina/química , Ligação de Hidrogênio , Modelos Moleculares , Teoria Quântica , Água/química
13.
J Mol Model ; 18(1): 265-74, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21523535

RESUMO

The microsolvation of taurine (TA) with one, two or three water molecules was investigated by a density functional theory (DFT) approach. Quantum theory of atoms in molecules (QTAIM) analyses were employed to elucidate the hydrogen bond (H-bond) interaction characteristics in TA-(H(2)O)(n) (n = 1-3) complexes. The results showed that the intramolecular H-bond formed between the hydroxyl and the N atom of TA are retained in most TA-(H(2)O)(n) (n = 1-3) complexes, and are strengthened via cooperative effects among multiple H-bonds from n = 1-3. A trend of proton transformation exists from the hydroxyl to the N atom, which finally results in the cleavage of the origin intramolecular H-bond and the formation of a new intramolecular H-bond between the amino and the O atom of TA. Therefore, the most stable TA-(H(2)O)(3) complex becomes a zwitterionic complex rather than a neutral type. A many-body interaction analysis showed that the major contributors to the binding energies for complexes are the two-body energies, while three-body energies and relaxation energies make significant contributions to the binding energies for some complexes, whereas the four-body energies are too small to be significant.


Assuntos
Taurina/química , Água/química , Ligação de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Prótons , Teoria Quântica , Soluções/química
14.
Palliative Care Research ; : 225-232, 2012.
Artigo em Japonês | WPRIM (Pacífico Ocidental) | ID: wpr-374749

RESUMO

<b>Purpose</b>: The aim of this study was to examine the effects of community-based self-help groups for cancer survivors form supportive functions and benefit findings. <b>Methods</b>: A survey consisting of two scales was conducted with a sample of 109. The first scale measured the benefit finding in cancer experience, and the second scale measured supportive functions of self-help groups. <b>Results</b>: Exploratory factor analyses indicated that “benefit finding scale” included four factors, and the supportive functions of self-help group could be classified into four aspects. Benefit findings were related to the supportive functions. <b>Conclusion</b>: These results imply that the participation in self-help group is related to positive cognition of cancer survivors.

15.
J Mol Model ; 17(11): 2781-96, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21287213

RESUMO

The microsolvation of aminoethanol (AE) with one, two, three or four water molecules was investigated using a density functional theory (DFT) approach. Quantum theory of atoms in molecules (QTAIM) analyses were employed to elucidate the hydrogen-bonding characteristics of AE-(H(2)O)( n ) (n = 1-4) complexes. The results showed that AE tends to break its intramolecular OH(AE)···N(AE) hydrogen bond (H-bond) upon microsolvation and form intermolecular H-bonds with water molecules, while complexes that retain the intramolecular OH(AE)···N(AE) H-bond show reduced stabilities. The intermolecular H-bond that forms between the nitrogen atom of AE and the hydroxyl of a water molecule is the strongest one for the most stable AE-(H(2)O)( n ) (n = 1-4) complexes, and as n increases from 1 to 4 they grow stronger. The partial covalent character of this H-bond was confirmed by QTAIM analyses. Many-body interaction analysis showed that the relaxation energies and two- and three-body energies make significant contributions to the binding energies of the complexes.


Assuntos
Etanolaminas/química , Teoria Quântica , Configuração de Carboidratos , Ligação de Hidrogênio , Modelos Moleculares , Água/química
16.
J Mol Model ; 17(10): 2609-21, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21258830

RESUMO

The hydrogen bonding interactions between noradrenaline (NA) and DMSO were studied with density functional theory (DFT) regarding their geometries, energies, vibrational frequencies, and topological features of the electron density. The quantum theory of atoms in molecules (QTAIM) and the natural bond orbital (NBO) analyses were employed to elucidate the hydrogen bonding interaction characteristics in noradrenaline-DMSO complexes. The H-bonds involving the hydroxyls hydrogen in NA and the O atom in DMSO are dominant intermolecular H-bonds and are stronger than other H-bonds involving the methyl hydrogen of DMSO as a H-donor. The weak H-bonds also include a π H-bond which involves the benzene ring as a H-donor or H-acceptor. QTAIM identified the weak H-bonds formed between the methyl hydrogen of DMSO and the N atom in NA in some complexes (AB5, AB6 and AB7), which cannot be further confirmed by NBO and other methods, so there are probably no interactions between hydrogen and nitrogen atoms among these complexes. A good linear relationship between logarithmic electron density (lnρ ( b )) at the bond critical point (BCP) and structural parameter (δR (H···Y)) was found. The formations of new H-bonds in some complexes are helpful to strengthen the original intramolecular H-bond, this is attributed to the cooperativity of H-bonds in complexes and can be learned from the structure results and the NBO and QTAIM analyses. Analysis of various physically meaningful contributions arising from the energy decomposition procedures show that the orbital interactions of H-bond is predominant during the formation of the complex, moreover, both the hydrogen bonding interaction and the structural deformation are responsible for the stability of the complexes.


Assuntos
Dimetil Sulfóxido/química , Norepinefrina/química , Ligação de Hidrogênio , Conformação Molecular , Teoria Quântica
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