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1.
Opt Express ; 31(3): 3536-3548, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785344

RESUMO

An analytical method is proposed in this paper to achieve complete energy conversion in sum frequency generation based on the Lewis-Riesenfeld invariants theory. In the proposed scheme, a quasi-adiabatic single control parameter model is established, and the value of single control parameter is selected to make the initial eigenstate perfectly converted to the final eigenstate as needed. Corresponding to the nonlinear frequency conversion process, a nonlinear crystal structure is designed by inverse engineering using the optimal control theory. It is robust against perturbations of the coupling coefficient and phase mismatch, including variations in the pump intensity and crystal polarization period, and achieves almost 100% conversion efficiency at any crystal length. Theoretical simulations show that frequency conversion can be achieved in the wavelength range of 2.6 µm-3.6 µm, and the spectral bandwidth of conversion efficiency exceeds 50% and approaches 400 nm when the crystal length L = 1 mm.

2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 149-154, 2023 Feb.
Artigo em Zh | MEDLINE | ID: mdl-36861169

RESUMO

Acute coronary syndrome (ACS),with increasing mortality year by year,has become a major public health problem in China.Exercise rehabilitation as an important part of the out-of-hospital rehabilitation for the patients with heart diseases can further reduce the mortality of patients on the basis of drug treatment.The available studies have proved that high-intensity interval training (HIIT) is more effective and efficient than moderate-intensity continuous training (MICT) such as walking and jogging on chronic cardiovascular diseases such as heart failure,stable coronary heart disease,and hypertension and has high security.According to the latest research,HIIT can reduce the platelet response,mitigate myocardial ischemia-reperfusion injury,and increase the exercise compliance of ACS patients more significantly than MICT.Moreover,it does not increase the risk of thrombotic adverse events or malignant arrhythmia.Therefore,HIIT is expected to become an important part of exercise prescription in out-of-hospital cardiac rehabilitation strategy for the patients with ACS.


Assuntos
Síndrome Coronariana Aguda , Reabilitação Cardíaca , Insuficiência Cardíaca , Treinamento Intervalado de Alta Intensidade , Humanos , Plaquetas
3.
Angew Chem Int Ed Engl ; 62(11): e202217458, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36640120

RESUMO

Constructing efficient artificial solid electrolyte interface (SEI) film is extremely vital for the practical application of lithium metal batteries. Herein, a dense artificial SEI film, in which lithiophilic Zn/Lix Zny are uniformly but nonconsecutively dispersed in the consecutive Li+ -conductors of Lix SiOy , Li2 O and LiOH, is constructed via the in situ reaction of layered zinc silicate nanosheets and Li. The consecutive Li+ -conductors can promote the desolvation process of solvated-Li+ and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of lithium ions, and lower the nucleation barrier. Therefore, a low polarization of ≈50 mV for 750 h at 2.0 mA cm-2 in symmetric cells, and a high capacity retention of 99.2 % in full cells with a high lithium iron phosphate areal loading of ≈13 mg cm-2 are achieved. This work offers new sights to develop advanced alkali metal anodes for efficient energy storage.

4.
Chemistry ; 28(31): e202200363, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35332603

RESUMO

As competitive next-generation rechargeable batteries, lithium-sulfur batteries (LSBs) suffer from the shuttle effect and the sluggish kinetics of intermediate polysulfides during charge and discharge processes, adversely affecting their electrochemical performances and actual applications. Herein, we demonstrate a polymer encapsulation strategy to synthesize atomic Fe and N co-doped hollow carbon nanospheres (Fe-NHC) with Fe-Nx sites for modifying commercial PP separator of LSBs to suppress the shuttle effect and promote the kinetics of intermediate polysulfides. Benefiting from the excellent structural design, the doped-N with positive charges could effectively adsorb negatively charged soluble polysulfides, help attract the soluble polysulfides to the Fe atoms and boost the catalytic transformation of the soluble polysulfides. Additionally, such a thin carbon shell could provide a short mass diffusion pathway and hence promote the adsorption and the catalytic conversion. Therefore, the battery with the Fe-NHC/PP separator delivers outstanding cycling and rate performances. At the large current density of 1 C, the specific capacity is 1079 mA h g-1 and maintains a low loss of 0.076 % per cycle within 500 cycles. Even at a harsh current density of 4 C, a high capacity of 824 mA h g-1 is still achieved, indicating the advantage of the Fe-NHC/PP separator in LSBs.

5.
Small ; 17(38): e2101857, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34350696

RESUMO

Although organosulfur compounds can protect lithium anodes, participate in the redox reaction, and suppress the shuttle effect, the sluggish electrochemical dynamics of their bulk structure and the notorious shuttle effect of covalent long-chain sulfurs largely impede their actual applications. Herein, sulfurized carbon nanotube@aminophenol-formaldehyde (SC@A) with covalently linked short-chain sulfurs is firstly synthesized by in situ polymerization of aminophenol-formaldehyde (AF) on the surface of carbon nanotubes (CNTs) followed by acetone etching and inverse sulfurization processes, forming mesoporous yolk-shell organosulfur nanotubes with abundant internal joints between the yolk of CNTs and the shell of sulfurized AF for the first time. In situ Raman spectra, in situ XRD patterns, and ex situ XPS spectra verify that the covalent short-chain sulfurs bring about a reversible solid-solid conversion process of sulfur, thoroughly avoiding the shuttle effect. The mesoporous yolk-shell structure with abundant internal joints can effectively accommodate the volume change, fully expose active sites and efficiently improve the transport of electrons and lithium ions, thus highly promoting the solid-solid electrochemical reaction kinetics. Therefore, the SC@A cathode exhibits a superior specific capacity of 841 mAh g-1 and a capacity decay of 0.06% per cycle within 500 cycles at a large current density of 5.0 C.

6.
Neuroradiology ; 60(2): 151-159, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29188303

RESUMO

PURPOSE: Petrous apex meningocele (PAM) is an uncommon cystic lesion involving the petrous apex. The underlying cause of PAM may be related to chronic elevated intracranial pressure. The aim of the study was to explore the relationship between PAM and meningioma and between PAM and other intracranial hypertension findings. METHODS: Two hundred seventy-eight consecutive patients with meningiomas were retrospectively studied. Fifty age- and gender-matched controls were also enrolled in this study. The incidence of PAM, empty sella, tortuosity of the optic nerve, and hydrops of optic nerve sheath was evaluated. The maximum width, area, volume of each PAM, or Meckel's cave and volume of meningioma were measured in controls and patients, separately. RESULTS: One hundred fifty-nine (57.19%) patients were detected with coexistent PAMs. One hundred twenty-five patients had bilateral PAMs, 34 had unilateral lesions, and the remaining 119 did not have PAM. Two subjects (4/50) had unilateral PAMs in normal controls. The maximum width, area, volume of PAM, or Meckel's cave were significantly larger in the patients with bilateral PAM group than those in the unilateral PAM group, in the group without PAM, and those in control group (p = 0.000). The volume of meningioma was positively correlated with the PAM volume (r = 0.48). There was a positive correlation for the incidence between PAM and (1) empty sella (r = 0.901) and (2) tortuosity of the optic nerves and hydrops of the optic sheath (r = 0.825). CONCLUSION: Coexistence of PAMs with meningiomas is not rare in incidence, and it suggests a potential role for chronically elevated intracranial pressure and disturbance of CSF circulation in their pathophysiology.


Assuntos
Hipertensão Intracraniana/complicações , Meningioma/complicações , Meningioma/diagnóstico por imagem , Meningocele/diagnóstico por imagem , Meningocele/etiologia , Osso Petroso/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Gadolínio DTPA , Humanos , Hipertensão Intracraniana/patologia , Imageamento por Ressonância Magnética , Masculino , Meningioma/patologia , Meningocele/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
J Therm Biol ; 69: 76-84, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29037408

RESUMO

In fish species with temperature-dependent sex determination (TSD) or genotypic sex determination plus temperature effects (GSD + TE), temperature can either affect sex differentiation or determine the sex. However, it is unknown if epigenetic control of cyp19a1a expression is critical for high temperature induced masculinization in the freshwater fish Nile tilapia. We analyzed the cyp19a1a DNA methylation levels in three age groups and found that they were lower in females than in males. At 8 months of age, males had DNA methylation levels of the cyp19a1a promoter that were almost twice as high as those of females. Exposure to high temperatures increased the cyp19a1a promoter DNA methylation levels from 30.87 ± 4.56% to 48.34 ± 0.92% (P = 0.035) in females and from 50.33 ± 7.38% to 51.66 ± 4.75% in males (P = 0.867). The increases in the cyp19a1a promoter DNA methylation levels were associated with the mRNA expression levels and might play a role in promoting gonadal differentiation in high temperature induced group females toward the male pathway. Western blot analysis revealed that the cyp19a1a protein expression levels in females significantly declined after high temperature treatment; only a slight decline was recorded in male fish. These results reveal that epigenetic control of cyp19a1a mRNA and protein expression is related to the environmental temperature and sex ratios in fish with TSD or GSD + TE.


Assuntos
Ciclídeos/genética , Família 19 do Citocromo P450/genética , Epigênese Genética , Proteínas de Peixes/genética , Processos de Determinação Sexual , Animais , Sequência de Bases , Ciclídeos/crescimento & desenvolvimento , Metilação de DNA , Feminino , Temperatura Alta , Masculino , Diferenciação Sexual
8.
J Foot Ankle Surg ; 56(2): 226-229, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28126375

RESUMO

We report our clinical experience with 11 cases of heel soft tissue defects treated with a medial plantar artery island pedicle flap. We also evaluated the functional outcomes of reconstruction. We enrolled 11 patients (10 [90.9%] males and 1 [9.1%] female), who received a medial plantar artery island pedicle flap for heel soft tissue defects from August 2010 to July 2014. The cause of the defects included trauma (post-traumatic heel skin necrosis) in 2 (18.2%) patients, infection (calcaneal osteomyelitis with overlying soft tissue infection) in 2 (18.2%) patients, and tumor (stage IA melanoma) in 7 (63.6%) patients. The mean average size of the defect was 3.7 cm × 4.4 cm (range 3.1 cm × 4.0 cm to 4.5  cm × 5.5  cm). The mean follow-up period was 19.6 (range 8 to 35) months, and all flaps survived within that period. The mean static 2-point discrimination was 34.4 (range 29 to 40) mm at the heel and 17.2 mm at the distal sole. The mean visual analog scale score for the aesthetic appearance of the reconstructed heel was 9 (range 8 to 9.5). The average revised Foot Function Index score was 25.8 (range 21 to 37). The medial plantar artery island pedicle flap is a versatile and effective method for reconstructing heel soft tissue defects.


Assuntos
Calcanhar/cirurgia , Retalhos Cirúrgicos/irrigação sanguínea , Adulto , Feminino , Seguimentos , Traumatismos do Pé/cirurgia , Sobrevivência de Enxerto , Calcanhar/lesões , Humanos , Masculino , Melanoma/cirurgia , Pessoa de Meia-Idade , Osteomielite/cirurgia , Neoplasias Cutâneas/cirurgia , Lesões dos Tecidos Moles/cirurgia , Escala Visual Analógica , Adulto Jovem
9.
Immunol Invest ; 45(1): 1-10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26700406

RESUMO

Allergic rhinitis (AR) is one of the common disorders in airway allergic inflammation. The pathogenesis of AR is unclear. It is accepted that immune deregulation is associated with the pathogenesis of AR. Recent reports suggest that a large number of micro RNAs (miR) can regulate immune functions. This study aims to investigate the role of miR-146a in an enforcing immunotherapy of AR. In this study, a mouse AR model was created. The levels of miR-146a in the mouse nasal mucosa were assessed by real time RT-PCR. A specific immunotherapy was performed in AR mice. The results showed that the AR mice had an AR-like inflammation in the nasal mucosa. Compared with naïve mice, markedly lower levels of miR-146a were detected in AR mice. The co-administration with miR-146a significantly enforced the effect of ovalbumin (OVA)-specific immunotherapy on inhibition of AR inflammation in the nasal mucosa. Further analysis showed that miR-146a induced transforming growth factor-ß in dendritic cells; the latter induced naïve CD4(+) T cells to differentiate into regulatory T cells. In conclusion, miR-146a can enforce OVA-specific immunotherapy via inducing antigen-specific regulatory T cells. miR-146a may have therapeutic potential to be used in the immunotherapy of allergic diseases.


Assuntos
Imunoterapia , MicroRNAs/genética , Rinite Alérgica/genética , Rinite Alérgica/imunologia , Animais , Estudos de Casos e Controles , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Epitopos de Linfócito T/imunologia , Expressão Gênica , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoterapia Adotiva , Contagem de Linfócitos , Masculino , Camundongos , Nanopartículas , Mucosa Nasal/citologia , Mucosa Nasal/imunologia , Mucosa Nasal/metabolismo , Ovalbumina/imunologia , Rinite Alérgica/diagnóstico , Rinite Alérgica/metabolismo , Rinite Alérgica/terapia , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Vacinas/imunologia
10.
Med Sci Monit ; 22: 3514-3522, 2016 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-27694792

RESUMO

BACKGROUND The aim of this study was to investigate the possible associations of miRNA-27a and Leptin polymorphisms with the risk of recurrent spontaneous abortion (RSA). MATERIAL AND METHODS Between May 2013 and April 2015 at Shenzhen Longhua New District Central Hospital, we randomly recruited 138 RSA patients as the case group and another 142 normal pregnancy women as the control group. We used denaturing high-performance liquid chromatography (DHPLC) to determine the genotypes and allele frequencies of miRNA-27a rs895819 A/G and Leptin rs7799039 G/A. RESULTS The GG genotype and G allele frequencies of miRNA-27a rs895819 A/G were higher in the case group than in the control group, and the AA genotype and A allele frequencies of Leptin rs7799039 G/A were also higher in the case group than in the control group (all P<0.05). MiRNA-27a rs895819 A/G and Leptin rs7799039 G/A polymorphisms increased the risk of RSA (Exp (B)=2.732, 95% CI=1.625~4.596, P=0.000; Exp (B)=4.081, 95% CI=1.817~9.164, P=0.001). GG-AA or AG-AA carriers had a higher risk of RSA. The miRNA-27a expression of AA carriers of miRNA-27a rs895819 was lower than that of AG+GG carriers both in the case and control groups (all P=0.024). The plasma leptin concentration of GG carriers was lower than that of GA+AA carriers in the case group (P=0.026). CONCLUSIONS The polymorphisms of miRNA-27a rs895819 A/G and Leptin rs7799039 G/A may contribute to an increased risk of RSA.


Assuntos
Aborto Habitual/genética , Frequência do Gene/genética , Predisposição Genética para Doença , Leptina/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Aborto Habitual/sangue , Adulto , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Feminino , Regulação da Expressão Gênica , Loci Gênicos , Humanos , Leptina/sangue , Modelos Logísticos , MicroRNAs/sangue , Gravidez , Fatores de Risco
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