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1.
Opt Lett ; 49(3): 746-749, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300105

RESUMO

As is well known, a light beam with a helical phase carries an optical orbital angular momentum (OAM), which can cause the orbital motion of trapped microparticles around the beam axis. Usually, the speed of the orbital motion is uniform along the azimuthal direction and depends on the amount of OAM and the light intensity. Here, we present the reverse customized method to tailor the nonuniform local OAM density along the azimuthal direction of the focal field, which has a hybrid polarization distribution and maintains a doughnut-shaped intensity profile. Theoretical analysis and experimental results about the orbital motion of the trapped polystyrene sphere show that the nonuniform local OAM density can be tailored by manipulating the polarization states of the focal field. Our results provide an ingenious way to control the local tangential optical force and the speed of the orbital motion of particles driven by the local OAM density and will promote exciting possibilities for exploring ways to control the mechanical dynamics of microparticles in optical trapping and microfluidics.

2.
Nature ; 558(7710): 410-414, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29892031

RESUMO

Optical frequency combs, which emit pulses of light at discrete, equally spaced frequencies, are cornerstones of modern-day frequency metrology, precision spectroscopy, astronomical observations, ultrafast optics and quantum information1-7. Chip-scale frequency combs, based on the Kerr and Raman nonlinearities in monolithic microresonators with ultrahigh quality factors8-10, have recently led to progress in optical clockwork and observations of temporal cavity solitons11-14. But the chromatic dispersion within a laser cavity, which determines the comb formation15,16, is usually difficult to tune with an electric field, whether in microcavities or fibre cavities. Such electrically dynamic control could bridge optical frequency combs and optoelectronics, enabling diverse comb outputs in one resonator with fast and convenient tunability. Arising from its exceptional Fermi-Dirac tunability and ultrafast carrier mobility17-19, graphene has a complex optical dispersion determined by its optical conductivity, which can be tuned through a gate voltage20,21. This has brought about optoelectronic advances such as modulators22,23, photodetectors 24 and controllable plasmonics25,26. Here we demonstrate the gated intracavity tunability of graphene-based optical frequency combs, by coupling the gate-tunable optical conductivity to a silicon nitride photonic microresonator, thus modulating its second- and higher-order chromatic dispersions by altering the Fermi level. Preserving cavity quality factors up to 106 in the graphene-based comb, we implement a dual-layer ion-gel-gated transistor to tune the Fermi level of graphene across the range 0.45-0.65 electronvolts, under single-volt-level control. We use this to produce charge-tunable primary comb lines from 2.3 terahertz to 7.2 terahertz, coherent Kerr frequency combs, controllable Cherenkov radiation and controllable soliton states, all in a single microcavity. We further demonstrate voltage-tunable transitions from periodic soliton crystals to crystals with defects, mapped by our ultrafast second-harmonic optical autocorrelation. This heterogeneous graphene microcavity, which combines single-atomic-layer nanoscience and ultrafast optoelectronics, will help to improve our understanding of dynamical frequency combs and ultrafast optics.

3.
Perfusion ; : 2676591241242018, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557237

RESUMO

Background: In lung transplantation surgery, extracorporeal life support (ECLS) is essential for safety. Various support methods, including cardiopulmonary bypass (CPB) and off-pump techniques, are used, with extracorporeal membrane oxygenation (ECMO) gaining prominence. However, consensus on the best support strategy is lacking.Purpose: This article reviews risks, benefits, and outcomes of different support strategies in lung transplantation. By consolidating knowledge, it aims to clarify selecting the most appropriate ECLS modality.Research Design: A comprehensive literature review examined CPB, off-pump techniques, and ECMO outcomes in lung transplantation, including surgical results and complications.Study Sample: Studies, including clinical trials and observational research, focused on ECLS in lung transplantation, both retrospective and prospective, providing a broad evidence base.Data Collection and/or Analysis: Selected studies were analyzed for surgical outcomes, complications, and survival rates associated with CPB, off-pump techniques, and ECMO to assess safety and effectiveness.Results: Off-pump techniques are preferred, with ECMO increasingly vital as a bridge to transplant, overshadowing CPB. However, ECMO entails hidden risks and higher costs. While safer than CPB, optimizing ECMO postoperative use and monitoring is crucial for success.Conclusions: Off-pump techniques are standard, but ECMO's role is expanding. Despite advantages, careful ECMO management is crucial due to hidden risks and costs. Future research should focus on refining ECMO use and monitoring to improve outcomes, emphasizing individualized approaches for LT recipients.

4.
Perfusion ; : 2676591241245876, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587932

RESUMO

PURPOSE: Exercise-based cardiac rehabilitation (EBCR) improves functional capacity in heart failure (HF). However, data on the effect of EBCR in patients with advanced HF and left ventricular assist devices (LVADs) are limited. This meta-analysis aimed to evaluate the impact of EBCR on the functional ability of LVAD patients by comparing the corresponding outcome indicators between the EBCR and ST groups. METHODS: PubMed, Embase, Clinical Trials, and Cochrane Library databases were searched for studies assessing and comparing the effects of EBCR and standard therapy (ST) in patients following LVAD implantation. Using pre-defined criteria, appropriate studies were identified and selected. Data from selected studies were extracted in a standardized fashion, and a meta-analysis was performed using a fixed-effects model. The protocol was registered on INPLASY (202340073). RESULTS: In total, 12 trials involving 477 patients were identified. The mean age of the participants was 52.9 years, and 78.6% were male. The initiation of EBCR varied from LVAD implantation during the index hospitalization to 11 months post-LVAD implantation. The median rehabilitation period ranged from 2 weeks to 18 months. EBCR was associated with improved peak oxygen uptake (VO2) in all trials. Quantitative analysis was performed in six randomized studies involving 214 patients (EBCR: n = 130, ST: n = 84). EBCR was associated with a significantly high peak VO2 (weighted mean difference [WMD] = 1.64 mL/kg/min; 95% confidence interval [CI], 0.20-3.08; p = .03). Similarly, 6-min walk distance (6MWD) showed significantly greater improvement in the EBCR group than in the ST group (WMD = 34.54 m; 95% CI, 12.47-56.42; p = .002) in 266 patients (EBCR, n = 140; ST, n = 126). Heterogeneity was low among the included trials. None of the included studies reported serious adverse events related to EBCR, indicating the safety of EBCR after LVAD implantation. CONCLUSION: This study demonstrated that EBCR following LVAD implantation is associated with greater improvement in functional capacity compared with ST as reflected by the improved peak VO2 and 6MWD values. Considering the small number of patients in this analysis, further research on the clinical impact of EBCR in LVAD patients is warranted.

5.
Nano Lett ; 23(9): 3921-3928, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37102437

RESUMO

Twisted photons can in principle carry a discrete unbounded amount of orbital angular momentum (OAM), which are of great significance for quantum communication and fundamental tests of quantum theory. However, the methods for characterization of the OAM quantum states present a fundamental limit for miniaturization. Metasurfaces can exploit new degrees of freedom to manipulate optical fields beyond the capabilities of bulk optics, opening a broad range of novel and superior applications in quantum photonics. Here we present a scheme to reconstruct the density matrix of the OAM quantum states of single photons with all-dielectric metasurfaces composed of birefringent meta-atoms. We have also measured the Schmidt number of the OAM entanglement by the multiplexing of multiple degrees of freedom. Our work represents a step toward the practical application of quantum metadevices for the measurement of OAM quantum states in free-space quantum imaging and communications.

6.
Phys Rev Lett ; 130(5): 050805, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800454

RESUMO

High-dimensional (HD) entanglement enables an encoding of more bits than in the two-dimensional case and promises to increase communication capacity over quantum channels and to improve robustness to noise. In practice, however, one of the central challenges is to devise efficient methods to quantify the HD entanglement explicitly. Full quantum state tomography is a standard technology to obtain all the information about the quantum state, but it becomes impractical because the required measurements increase exponentially with the dimension in HD systems. Hence, it is highly anticipated that a new method will be found for characterizing the HD entanglement with as few measurements as possible and without introducing unwarranted assumptions. Here, we present and demonstrate a scan-free tomography method independent of dimension, which only requires two measurements for the characterization of two-photon HD orbital angular momentum (OAM) entanglement. Taking Laguerre-Gaussian modes of photons as an example, the density matrices of OAM entangled states are experimentally reconstructed with very high fidelity. Our method is also generalized to the mixed HD OAM entanglement. Our results provide realistic approaches for quantifying more complex OAM entanglement in many scientific and engineering fields such as multiphoton HD quantum systems and quantum process tomography.

8.
BMC Cardiovasc Disord ; 23(1): 602, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066423

RESUMO

BACKGROUND: Chronic coronary syndrome (CCS) is a major public health burden; its pathogenesis involves atherosclerosis and endothelial dysfunction. Endothelin-1 (ET-1) and nitric oxide (NO) are vasoactive substances synthesized by endothelial cells that play a crucial role in CCS development. The Gensini score (GS) is used for evaluating CCS severity based on lumen segment changes, stenosis degree, and coronary stenosis site. METHODS: This prospective study included 71 patients with CCS; we evaluated the relationships between GS and ET-1 and NO serum levels were evaluated in these patients. The GS was calculated for all patients. Serum ET-1 & NO levels among other laboratory parameters were measured. RESULTS: The high GS group had higher ET-1 and relatively NO expressions in the than the low GS group. GS was positively correlated with ET-1 and negatively correlated with NO, T4, and TSH levels. The results of the multiple linear regression analysis showed that ET-1 had the most significant effect on GS. CONCLUSIONS: We found a strong association between ET-1, NO, and CCS severity. A combination of ET-1, NO, and GS is an essential predictor of CCS disease severity.


Assuntos
Doença da Artéria Coronariana , Endotelina-1 , Humanos , Angiografia Coronária , Óxido Nítrico , Estudos Prospectivos , Células Endoteliais , Síndrome , Índice de Gravidade de Doença
9.
Artif Organs ; 47(7): 1163-1173, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36638047

RESUMO

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been widely used in high-risk acute myocardial infarction (AMI) patients with promising outcomes. However, the underlying molecular mechanisms remain unknown and a VA-ECMO animal model has not yet been established. The purpose of this study was to establish a VA-ECMO model in AMI rats and evaluate long-term cardiac function. METHODS: We first established AMI in 20 Sprague-Dawley (SD) rats by ligating the left anterior descending coronary artery, while five rats underwent a thoracotomy to form the sham group. VA-ECMO was established after 30mins of AMI in 10 rats through the right jugular vein for venous drainage and right femoral artery for arterial infusion. Arterial blood pressure was monitored using a catheter in the left femoral artery, blood gas parameters were measured using a blood gas analyzer, while myocardial enzymes were detected using an ELISA Kit. Cardiac function was assessed through echocardiography on day 15. Masson staining and Western Blot were used for evaluating myocardial fibrosis, while histological injury was evaluated using hematoxylin and eosin staining. RESULTS: VA-ECMO support stabilized blood pressure, decreased the levels of myocardial enzymes including cTnI, cTnT, CK-MB, and was associated with a higher survival rate. In the long term, the VA-ECMO group showed improved cardiac function, significantly increased EF and FS but significantly decreased EDV and ESV compared to the AMI group. Furthermore, VA-ECMO significantly alleviated pathological damage and myocardial fibrosis. CONCLUSION: We established an economical, reliable, and reproducible VA-ECMO animal model in AMI rats, and demonstrated that VA-ECMO support prevents deteriorated cardiac function.


Assuntos
Oxigenação por Membrana Extracorpórea , Infarto do Miocárdio , Animais , Ratos , Ratos Sprague-Dawley , Infarto do Miocárdio/terapia , Artéria Femoral , Fibrose , Choque Cardiogênico , Estudos Retrospectivos
10.
Perfusion ; 38(1): 6-17, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263684

RESUMO

OBJECTIVE: Although the application of del Nido cardioplegia solution (DNC) in adult cardiac surgery is accumulating, the feasibility and safety of this myocardial protection strategy in adults remains controversial. We aimed to update our previous meta-analysis to determine the myocardial protective effect of DNC versus conventional cardioplegia (CC) in adult cardiac surgery. METHODS: A comprehensive literature search was performed using PubMed, EMBASE, the Cochrane Library, and International Clinical Trials Registry Platform databases through November 2020. RESULTS: Thirty-seven observational studies and four randomized controlled trials (RCTs) including 21,779 patients were identified. The DNC group was associated with decreased postoperative cardiac enzymes [troponin T (cTnT) and creatine kinase-MB (CK-MB)] [standardized mean differences (SMD): -0.59, 95% confidence interval (CI): -0.99 to -0.19, p = 0.004], cardiopulmonary bypass (CPB) time (MD: -9.31, 95% CI: -13.10 to -5.51, p < 0.00001), aortic cross-clamp (ACC) time (MD: -7.20, 95% CI: -10.31 to -4.09, p < 0.00001), and cardioplegia volume (SMD: -1.95, 95% CI: -2.46 to -1.44, p < 0.00001). Intraoperative defibrillation requirement was less in the DNC group [relative risk (RR): 0.50, 95% CI: 0.33 to 0.75, p = 0.0007]. The pooled analysis revealed no significant difference in operative mortality among the patients assigned to DNC and those undergoing CC. CONCLUSION: In adult cardiac surgery, compared to CC, myocardial protection used with DNC yield similar or better short-term clinical outcomes. More high-quality trials and RCTs reflecting long-term follow-up morbidity and mortality are required in the future to confirm these findings.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Soluções Cardioplégicas , Adulto , Humanos , Soluções Cardioplégicas/uso terapêutico , Parada Cardíaca Induzida , Miocárdio , Período Pós-Operatório , Estudos Retrospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Perfusion ; 38(1): 85-91, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34378461

RESUMO

INTRODUCTION: Venovenous extracorporeal membrane oxygenation (VV ECMO) is now considered a reasonable option to salvage acute respiratory distress syndrome (ARDS). However, we lack a rodent model for experimental studies. This study was undertaken to establish an animal model of VV ECMO in ARDS rats. METHODS: A total of 18 Sprague-Dawley (SD) rats (350 ± 50 g) were used in this study. Using a rat model of oleic acid (OA)-induced ARDS, VV ECMO was established through cavoatrial cannulation of the right jugular vein for venous drainage and venous reinfusion with a specially designed three-cavity catheter. Continuous arterial pressure monitoring was implemented by using a catheter through cannulation of the right femoral artery. The central temperature was monitored with a rectal probe. Arterial blood gas monitoring was implemented by a blood gas analyzer at three-time points: at baseline, 1-hour (after OA modeling), and 3.5-hour (after VV ECMO support). Lung tissue and bronchoalveolar lavage fluid were harvested respectively for protein concentration and pulmonary histologic evaluation to confirm the alleviation of lung injury during VV ECMO. RESULTS: Following ARDS induced by OA, ten rats were successfully established on VV ECMO without failure and survived the ECMO procedure. VV ECMO alleviated lung injury and restored adequate circulation for the return of lung function and oxygenation. VV ECMO was associated with decreased lung injury score, wet/dry weight ratio, and fluid leakage into airspaces. CONCLUSION: We have established a reliable, economical, and functioning ARDS rat model of VV ECMO.


Assuntos
Oxigenação por Membrana Extracorpórea , Lesão Pulmonar , Síndrome do Desconforto Respiratório , Ratos , Animais , Oxigenação por Membrana Extracorpórea/métodos , Ratos Sprague-Dawley , Artéria Femoral , Síndrome do Desconforto Respiratório/terapia
12.
Perfusion ; 38(6): 1107-1122, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35608047

RESUMO

OBJECTIVE: Although the application of venovenous extracorporeal membrane oxygenation (VV-ECMO) in coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome (ARDS) is accumulating, the feasibility and safety of this therapy remain controversial. We aimed to evaluate the effect of VV-ECMO in the treatment of these patients. METHODS: A comprehensive literature search was performed using PubMed, Embase, the Cochrane Library, and International Clinical Trials Registry Platform databases through November 2021. According to the inclusion and exclusion criteria, the included studies were screened, and meta-analysis was performed by R software (version 4.0.2). RESULTS: Forty-two studies including 2037 COVID-19 patients supported with VV-ECMO due to ARDS were identified. The pooled analysis revealed that 30-, 60-, and 90-day mortality among patients were respectively 46% (95% CI 37%-57%, I2 = 66%), 46% (95% CI 30%-70%, I2 = 93%), and 49% (95% CI 43%-58%, I2 = 52%), and the pooled incidence rate of in-hospital mortality, major bleeding, hemorrhagic stroke, thrombosis, pulmonary embolism, deep venous thrombosis, and renal replacement therapy were respectively 35%, 39%, 11%, 40%, 15%, 21%, and 44%. CONCLUSION: Although COVID-19 patients may have a higher risk of bleeding, hemorrhagic stroke, and acute kidney injury during ECMO therapy, the survival rate was more than half of the cases. Our data may support the application of VV-ECMO in COVID-19 patients.


Assuntos
COVID-19 , Oxigenação por Membrana Extracorpórea , Acidente Vascular Cerebral Hemorrágico , Síndrome do Desconforto Respiratório , Humanos , COVID-19/terapia , COVID-19/complicações , Oxigenação por Membrana Extracorpórea/efeitos adversos , Acidente Vascular Cerebral Hemorrágico/complicações , Hemorragia/etiologia , Síndrome do Desconforto Respiratório/etiologia , Estudos Retrospectivos
13.
Perfusion ; : 2676591221131217, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36206156

RESUMO

INTRODUCTION: Although venovenous extracorporeal membrane oxygenation (VV ECMO) is a reasonable salvage treatment for acute respiratory distress syndrome (ARDS), it requires sedating the patient. Sevoflurane and propofol have pulmonary protective and immunomodulatory properties. This study aimed to compare the effectiveness of sevoflurane and propofol on rats with induced ARDS undergoing VV ECMO. METHODS: Fifteen sprague-dawley (SD) rats were randomly divided into three groups: Con group, sevoflurane (Sevo) group and propofol (Pro) group. Arterial blood gas tests were performed at time pointsT0 (baseline), T1 (the time to ARDS), and T2 (weaning from ECMO). Oxygenation index (PaO2/FiO2) was calculated, and lung edema assessed by determining the lung wet:dry ratio. The protein concentration in bronchial alveolar lavage fluid (BALF) was determined by using bicinchoninic acid assay. Haematoxylin and eosin staining was used to evaluate the lung pathological scores in each group. IL-1ß and TNF-α were also measured in the BALF, serum and lung. RESULTS: Oxygenation index showed improvement in the Sevo group versus Pro group. The wet:dry ratio was reduced in the Sevo group compared with propofol-treated rats. Lung pathological scores were substantially lower in the Sevo group versus the Pro group. Protein concentrations in the BALF and levels of IL-1ß and TNF-α in the Sevo group were substantially lower versus Pro group. CONCLUSION: This study demonstrates that compared with propofol, sevoflurane was more efficacious in improving oxygenation and decreasing inflammatory response in rat models with ARDS subject to VV ECMO treatment.

14.
J Card Surg ; 36(9): 3441-3444, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34091978

RESUMO

We reported an exceedingly rare adult case of intracardiac teratoma with a bicuspid aortic valve. A small mass was discovered in the right ventricle of a 37-year-old man by accident after he was referred to our hospital due to chronic chest distress and aggravated palpitation. We performed a surgical exploration with excision of the lesion after a repeat transthoracic echocardiography suggested a space-occupying lesion in the interventricular septum. A mature cystic teratoma was pathologically confirmed. During the half-year follow-up, no symptoms were reported. This case constitutes the first report of the smallest primary intracardiac teratoma in an adult with a bicuspid aortic valve.


Assuntos
Doença da Válvula Aórtica Bicúspide , Teratoma , Septo Interventricular , Adulto , Ecocardiografia , Humanos , Achados Incidentais , Masculino , Teratoma/diagnóstico por imagem , Teratoma/cirurgia
15.
Perfusion ; 36(7): 724-736, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33016239

RESUMO

BACKGROUND: Redo coronary artery bypass grafting (redo CABG) is associated with increased mortality and morbidity. The aim of this study was to systematically evaluate the evidence comparing the outcomes of off-pump with on-pump redo CABG. METHODS: Studies were systematically searched and identified using PubMed, EMBASE, the Cochrane Library, and the International Clinical Trials Registry Platform (ICTRP) by two researchers independently. The primary outcome was 30-day mortality, and the secondary outcomes were in-hospital mortality, post-operative complications, completeness of revascularization, blood transfusion rate, duration of mechanical ventilation, intensive care unit and hospital stays. RESULTS: The 21 studies including 4,889 patients were enrolled in our meta-analysis. Compared with on-pump, the off-pump technique was associated with significantly reduced 30-day mortality (odds ratio [OR] = 0.43, 95% confidence interval [CI] = 0.26-0.72, p = 0.001). Moreover, a notably decreased in-hospital mortality (OR = 0.55, 95% CI = 0.39-0.76, p = 0.0004) and incidence of post-operative new-onset atrial fibrillation, myocardial infarction, acute kidney injury, low cardiac output state, blood transfusion rate (OR = 0.46, 95% CI = 0.35-0.60, p < 0.00001; OR = 0.54, 95% CI = 0.38-0.78, p = 0.0007; OR = 0.51, 95% CI = 0.37-0.70, p < 0.0001; OR = 0.31, 95% CI = 0.20-0.47, p < 0.00001; OR = 0.29, 95% CI = 0.14-0.61, p = 0.001) and significantly shortened duration of mechanical ventilation, intensive care unit and hospital stays (mean difference [MD] = -8.21 h, 95% CI = -11.74 to -4.68, p < 0.00001; MD = -0.77 d, 95% CI = -0.81 to -0.73, p < 0.00001; MD = -2.24 d, 95% CI = -3.17 to -1.32, p < 0.00001) could be observed when comparing the outcomes of off-pump with on-pump redo CABG. There was nonsignificant difference between off-pump and on-pump redo CABG in completeness of revascularization. CONCLUSION: In patients undergoing redo CABG surgery, the off-pump technique was associated with decreased mortality, less post-operative complications when compared to on-pump.


Assuntos
Ponte de Artéria Coronária sem Circulação Extracorpórea , Infarto do Miocárdio , Ponte de Artéria Coronária , Ponte de Artéria Coronária sem Circulação Extracorpórea/efeitos adversos , Mortalidade Hospitalar , Humanos , Tempo de Internação , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
17.
Opt Express ; 28(16): 23416-23432, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32752339

RESUMO

A theoretical analysis based on mirror symmetry is proposed to analyze and predict the symmetry in intensity, phase and polarization distributions of the tightly focused vector optical field (VOF). We extend the analysis to more cases including more complicated polarization states and weak focusing cases. We further show the symmetric tightly focused fields of the eccentric cylindrical VOF and the redesigned VOF with a radially variant polarization state, which are achieved by redesigning the polarization state of the incident VOF based on the symmetry analysis. We also take the laser fabrication as an example to further show how to apply this symmetry analysis in a specific application area. Such a theoretical analysis can improve the calculation efficiency, provide new insights into the tight focusing process and offer a convenient way to engineer the field distributions in the focal plane, which may have potential applications in areas needing flexibly controllable tightly focused fields, such as laser fabrication, optical trapping, and optical storage.

18.
Opt Lett ; 45(7): 1738-1741, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32235987

RESUMO

Bessel-like beams with controllable rotation of local linear polarization upon propagation are generated, which in fact achieve the evolution of polarization states along the equator of the Poincaré sphere during propagation. Based on the amplitude-phase joint modulation method, the rotation direction and rate of polarizations of the Bessel-like beam can be controlled easily by adjusting the radial indices and intensity ratio of two superposed beams. A rotation angle of $\sim$∼800 deg has been achieved after a propagation distance of 120 mm, corresponding to a rotation rate of $\sim$∼6.7 deg/mm, which is about three times higher than in previous works.

19.
Opt Lett ; 45(3): 682-685, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32004284

RESUMO

Phase memory is an effect in which the interaction between a coherent pump beam and a nonlinear crystal generates photon pairs via the spontaneous parametric down-conversion process, then the down-converted photons (signal and idler) can carry the phase information of the pump beam. There has been much research on the memory of the dynamic phase so far; however, there is no report on the memory of non-dynamic phase, to the best of our knowledge. Here we acquire a Pancharatnam-Berry (PB) geometric phase in a physical system when light travels along a trajectory in polarization-state space. Induced coherence occurs in a cascaded scheme composed of two nonlinear crystals, when the idler photons in both crystals are aligned to be indistinguishable. A NOON ($N\; = \;{2}$N=2) state is established when blocking the two idler photons. We explore the PB geometric phase memory of the NOON state and induced coherence. We find that the first-order interference of the two-photon state or signal photons can be controlled by introducing the PB geometric phase to the pump light. This may facilitate precise control of the phase of the down-converted photons.

20.
J Nutr ; 150(9): 2469-2477, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32614453

RESUMO

BACKGROUND: High linoleic acid (LA) intake leads to inflammation that adversely influences health in fish. However, whether the farnesoid X receptor (FXR) could be an effective target for regulating LA-induced inflammation remains unknown. OBJECTIVE: The purpose of this study was to investigate the role of FXR in the regulation of LA-induced inflammation in large yellow croakers. METHODS: Large yellow croakers (initial weight of 10.03 ± 0.02 g) were allocated to 4 groups and fed a fish oil diet (6% FO), a soybean oil diet (6% SO), or the SO diet supplemented with 300 or 900 mg chenodeoxycholic acid (CDCA)/kg for 10 wk. The cultured kidney cell line PCK and primary hepatocytes from large yellow croakers were stimulated by LA (50 µM) after pretreatment with an FXR ligand (GW4064 or CDCA) or transfection with fxr-small interfering RNA (siFXR). mRNA expression of proinflammatory genes in the head kidney and liver tissues, PCK cells, and primary hepatocytes was determined by qPCR. The luciferase reporter assay, electrophoretic mobility shift assay, and immunoprecipitation assay were conducted in HEK 293T cells to determine the transcriptional activity of P65 and protein interactions between P65 and FXR or the small heterodimer partner (SHP). RESULTS: Proinflammatory genes were 93-1180% higher in the SO group compared with the FO group. CDCA supplementation decreased mRNA expression of proinflammatory genes by 17-87% while increasing fxr and shp expression by 120-460%. In PCK cells and primary hepatocytes, ligand-mediated activation of FXR decreased the LA-induced expression of proinflammatory genes by 18-67%, whereas siRNA-mediated knockdown of FXR increased the LA-induced expression of proinflammatory genes by 64-96%. FXR bound to the promoter of shp and regulated its mRNA expression. Both FXR and SHP could bind to P65 to suppress the transcriptional activity of P65. CONCLUSIONS: These results indicate that FXR has anti-inflammatory properties in large yellow croakers by directly and indirectly suppressing NFκB activity.


Assuntos
Ácido Quenodesoxicólico , Inflamação , Ácido Linoleico , Perciformes , Receptores Citoplasmáticos e Nucleares , Óleo de Soja , Animais , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Linhagem Celular , Ácido Quenodesoxicólico/administração & dosagem , Ácido Quenodesoxicólico/farmacologia , Dieta/veterinária , Óleos de Peixe , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Inflamação/induzido quimicamente , Inflamação/prevenção & controle , Inflamação/veterinária , Rim/citologia , Ácido Linoleico/efeitos adversos , Perciformes/fisiologia , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Óleo de Soja/administração & dosagem
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