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1.
Opt Lett ; 47(13): 3223-3226, 2022 Jul 01.
Article in English | MEDLINE | ID: mdl-35776590

ABSTRACT

The propagation-dependent spatial entanglement for the structured laser beams generated by an arbitrary incident Hermite-Gaussian (HG) mode passing through an astigmatic mode converter (AMC) is theoretically explored. The structured output beams are analytically decomposed into the expansion of HG modes for any given rotation angle of the AMC. Based on the Schmidt decomposition, the propagation-dependent spatial entanglements of the structured output modes are quantified with the von Neumann entropy. To manifest the propagation-dependent entropy, the probability distribution of the expanded HG modes in the structured output beam is quantitatively analyzed.

2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(9): 1607-1614, 2021 Sep 10.
Article in Chinese | MEDLINE | ID: mdl-34814591

ABSTRACT

Objective: To evaluate the association of hyperuricemia with the risk for chronic kidney disease (CKD) in community adults. Methods: A community-based follow-up study comprising of 7 276 adults aged 20-74 years who attended the natural population cohort in Eastern China and had no CKD at baseline survey was performed in the Songjiang district, Shanghai. CKD was diagnosed according to the National Kidney Foundation Practice Guidelines for Chronic Kidney Disease criteria. Hyperuricemia was defined as serum uric acid level >420 µmol/L for men and >360 µmol/L for women. Cox proportional hazards model was used to examine the association of hyperuricemia with the risk for CKD. Results: During a median follow-up period of 2.65 year, 301 participants were newly diagnosed with CKD. The cumulative incidence rate and incidence density of CKD were 4.14%, and 16.01/1 000 person-years (95%CI: 14.20-17.82), respectively. A higher prevalence of hyperuricemia was observed in subjects with CKD compared with those without CKD. Multivariate Cox regression model analysis showed that hyperuricemia was associated with the increased risk for CKD, with an adjusted HR of 1.92 (95%CI: 1.46-2.53). Their positive associations remained in almost all the subgroups, including sex, age (<60, ≥60 years), BMI (<25.0, ≥25.0 kg/m2), type 2 diabetes, and hypertension. A significant synergistic effect of the interaction between age and hyperuricemia on CKD was found, and the synergy index was 1.78 (95%CI: 1.18-2.68). Conclusion: The incidence of CKD in adults in Songjiang district was relatively high. Hyperuricemia is an independent risk factor for the development of CKD.


Subject(s)
Diabetes Mellitus, Type 2 , Hyperuricemia , Renal Insufficiency, Chronic , Adult , China/epidemiology , Female , Follow-Up Studies , Humans , Hyperuricemia/epidemiology , Male , Middle Aged , Renal Insufficiency, Chronic/epidemiology , Risk Factors , Uric Acid
3.
Opt Lett ; 46(20): 5129-5132, 2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34653132

ABSTRACT

Quantum entanglement by a beam splitter (BS) is shown to be analogous to laser mode transformation by an astigmatic mode converter (AMC). Schmidt decomposition is used to characterize the entanglement by an AMC for generating orbital angular momentum and by a BS for creating quantum photon interference. The probability distributions of Schmidt decomposition are calculated to manifest the sameness and difference between AMC and BS in generating entanglement. Finally, the theoretical patterns of mode transformations by an AMC are confirmed with experimental results to validate the present analysis.

4.
Opt Lett ; 46(15): 3713-3716, 2021 Aug 01.
Article in English | MEDLINE | ID: mdl-34329263

ABSTRACT

The Schmidt decomposition is exploited to study the spatial entanglement of laser transverse modes analogous to quantum Lissajous states. Based on the inverse Fourier transform, the stationary Lissajous state can be analytically derived as a coherent superposition of degenerate Hermite-Gaussian eigenmodes. With the derived stationary state, the Schmidt modes and the participation number N can be employed to evaluate the spatial localization and the quantum entanglement. The larger the participation number, the more localized is the stationary coherent state on the Lissajous figure. Moreover, the larger the participation number, the higher is the spatial entanglement.

5.
Opt Lett ; 46(7): 1588-1591, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-33793494

ABSTRACT

The coupled rate equations with the spatial overlap effect for four-level passively Q-switched lasers are fully considered. A transcendental equation is derived for the residual fraction of the inversion density after the finish of the Q-switched pulse. Comprehensive calculations for the transcendental equation were executed to attain an analytical function for precisely fitting the residual fraction of the inversion density. With the fitting function, a pedagogical model with the correction for high output coupling is developed to straightforwardly analyze the output pulse energy and peak power. Detailed experiments are carried out to validate the model.

6.
Opt Lett ; 46(9): 2063-2066, 2021 May 01.
Article in English | MEDLINE | ID: mdl-33929419

ABSTRACT

We demonstrate a highly powerful acousto-optically Q-switched Nd:YVO4 yellow laser at 589 nm by using a Np-cut KGW crystal and a phase-matching lithium triborate crystal to performance the intracavity stimulated Raman scattering and second-harmonic generation, respectively. We experimentally verify that the design of the separate cavity is superior to the conventional design of the shared cavity. By using the separate cavity, the optical-to-optical efficiency can be generally higher than 32% for the repetition rate within 200-500 kHz. The maximum output power at 589 nm can be up to 15.1 W at an incident pump power of 40 W and a repetition rate of 400 kHz.

7.
Opt Lett ; 46(1): 102-105, 2021 Jan 01.
Article in English | MEDLINE | ID: mdl-33362018

ABSTRACT

In this Letter, we experimentally explore the propagation-dependent evolution of generating the pseudo-nondiffracting quasi-crystalline (crystalline) beams based on the multibeam interference. We originally derived an analytical formula to exactly manifest the propagation evolution of interfering multiple beams. With the analytical formula, the formation of quasi-crystalline structures in the focal plane can be explicitly verified. Furthermore, the distance of the effective propagation-invariant region can be verified in terms of experimental parameters. More importantly, we employed the developed formula to confirm the formation of kaleidoscopic vortex lattices by means of numerically computing the propagation-dependent phase singularities.

8.
Opt Express ; 28(2): 936-947, 2020 Jan 20.
Article in English | MEDLINE | ID: mdl-32121813

ABSTRACT

The integral representation of the Zernike radial functions is well approximated by applying the Riemann sums with a surprisingly rapid convergence. The errors of the Riemann sums are found to averagely be not exceed 3 ×10-14, 3.3×10-14, and 1.8×10-13 for the radial order up to 30, 50, and 100, respectively. Moreover, a parallel algorithm based on the Riemann sums is proposed to directly generate a set of radial functions. With the aid of the graphics processing units (GPUs), the algorithm shows an acceleration ratio up to 200-fold over the traditional CPU computation. The fast generation for a set of Zernike radial polynomials is expected to be valuable in further applications, such as the aberration analysis and the pattern recognition.

9.
Clin Radiol ; 75(5): 395.e17-395.e24, 2020 05.
Article in English | MEDLINE | ID: mdl-31924327

ABSTRACT

AIM: To compare the uniformity and image quality between contrast media injection protocols adjusted for patient body weight (BW) versus body surface area (BSA) during coronary computed tomography (CT) angiography (CCTA). MATERIALS AND METHODS: Consecutive patients (n=489) with suspected coronary artery disease were randomised prospectively to one of two CCTA protocols. In the BW protocol (n=245), patients received individualised iodine delivery rates (≤50 kg: 1 g/s; 51-60 kg: 1.2 g/s; 61-70 kg: 1.4 g/s; 71-80 kg: 1.6 g/s; 81-90 kg: 1.8 g/s; 91-100 kg: 2 g/s; >100 kg: 2.2 g/s). In the BSA protocol (n=244), patients received 9,600 mg iodine/m2 of contrast medium over 12 seconds. Attenuation and image noise were measured. Signal-to-noise ratio and contrast-to-noise ratio were calculated. Image quality was scored. Attenuation was assessed for correlation with BW and BSA using linear regression. RESULTS: There were no statistically significant differences in mean arterial attenuation (396.8±47.6 versus 395.8±42.2 HU, p=0.804; 95% confidence interval: -7 to 9), image noise (25.2±5.8 versus 25.5±5.4 HU; p=0.549), signal-to-noise ratio (16.7±4.4 versus 16.6±3.6; p=0.902), contrast-to-noise ratio (25.1±5.8 versus 25.8±7.4; p=0.258) or image quality scores (4.1±0.9 versus 4±0.9; p=0.770) between the BW and BSA protocols. There was no correlation between BW and aortic attenuation or between BSA and aortic attenuation (p=0.324 and 0.932, respectively). CONCLUSION: The average contrast media attenuation and image quality was comparable between BW-adjusted protocol and BSA-adjusted protocol.


Subject(s)
Body Surface Area , Body Weight , Computed Tomography Angiography , Contrast Media/administration & dosage , Coronary Angiography , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies , Signal-To-Noise Ratio
12.
Opt Lett ; 44(12): 3034-3037, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-31199374

ABSTRACT

The formation of thermally detuned transverse patterns of a broad-area square-aperture vertical-cavity surface-emitting laser (VCSEL) via cryogenic cooling is explored. It is found that the transverse wave vector gradually rotates from the horizontal or vertical direction to the diagonal direction of the square boundary as the transverse mode order increases. A model based on the quantum billiards with a finite potential well is developed to emulate the transition behavior of lasing modes. Combining the effective modal gain analysis with the response wave function of driven finite potential billiards, all experimental lasing patterns under different operation temperatures are well reconstructed.

13.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(12): 1555-1559, 2018 Dec 10.
Article in Chinese | MEDLINE | ID: mdl-30572377

ABSTRACT

Objective: To investigate the prevalence and associated factors of chronic kidney diseases (CKD) in adult residents living in a community of Songjiang district, Shanghai. Methods: A total of 9 257 residents aged 20-75 years old in Xinqiao township of Songjiang district were selected by random cluster sampling. All the participants were interviewed to complete a set of personal questionnaire and undergo physical examinations. Urine and blood tests including markers of kidney damage and related associated factors with CKD, were carried out. Results: Eligible data from 8 207 subjects were enrolled in the study. After adjustment for age and gender, the prevalence of CKD was 8.4% (95%CI: 7.8%-9.0%), with majority of the patients (76.5%) appeared in the early stage (Ⅰ and Ⅱ) of the disease. The prevalence of CKD increased with age and higher prevalence was seen in females than in males (P<0.001). Results from logistic regression analysis showed that factors as: being elderly or female, having hypertension, hyperuricemia, and hyperlipidemia were all independently associated with CKD. Conclusions: The prevalence of CKD appeared relatively high in adult residents of Xinqiao township, Songjiang district where CKD had become a public health problem. Factors as: being female or elderly, hypertension, hyperuricemia, and hyperlipidemia were found to be associated with CKD. Our findings suggested that early prevention and control on CKD to reduce the incidence of end-stage renal diseases and related complications had called for more urgent attention.


Subject(s)
Hyperlipidemias/epidemiology , Hypertension/epidemiology , Hyperuricemia/epidemiology , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/epidemiology , Adult , Age Factors , Aged , China/epidemiology , Cross-Sectional Studies , Female , Humans , Hyperuricemia/ethnology , Male , Middle Aged , Prevalence , Renal Insufficiency, Chronic/ethnology , Risk Factors , Sex Factors , Young Adult
14.
Cryo Letters ; 39(1): 1-6, 2018.
Article in English | MEDLINE | ID: mdl-29734410

ABSTRACT

BACKGROUND: The microchannel heat exchange system has several advantages and can be used to enhance heat transfer for vitrification. OBJECTIVE: To evaluate the microchannel cooling method and to analyze the effects of key parameters such as channel structure, flow rate and sample size. MATERIALS AND METHODS: A computational flow dynamics model is applied to study the two-phase flow in microchannels and its related heat transfer process. The fluid-solid coupling problem is solved with a whole field solution method (i.e., flow profile in channels and temperature distribution in the system being simulated simultaneously). RESULTS AND CONCLUSION: Simulation indicates that a cooling rate >104 C/min is easily achievable using the microchannel method with the high flow rate for a board range of sample sizes. Channel size and material used have significant impact on cooling performance. Computational flow dynamics is useful for optimizing the design and operation of the microchannel system.


Subject(s)
Cells/metabolism , Cold Temperature , Cryopreservation/methods , Models, Theoretical , Organ Specificity , Vitrification , Hot Temperature , Phase Transition , Time Factors
15.
Zhonghua Xin Xue Guan Bing Za Zhi ; 45(6): 491-495, 2017 Jun 24.
Article in Chinese | MEDLINE | ID: mdl-28648025

ABSTRACT

Objective: To compare the characteristics of aortic valve dysfunction and ascending aorta dimension in patients with different bicuspid aortic valve (BAV) morphology. Methods: A total of 197 patients who underwent aortic valve replacement between April 2014 and March 2015 and were diagnosed with BAV by pathology were included, and their clinical data were retrospectively analyzed. Patients were divided into raphe(+) group(109 cases) and raphe(-) group(88 cases) according to the presence or absence of raphe, and L-R group(fusion of left and right cusp, 125 cases) and L/R-N group(fusion of left or right and noncoronary cusp, 72 cases) according to fusion type of the cusps. The characteristics of aortic valve dysfunction and ascending aorta dimension in patients with different BAV morphology were compared. Results: (1) Aortic stenosis incidence was lower in raphe(+) group than in raphe(-) group(22.9%(25/109) vs. 69.3%(61/88), P<0.001). Aortic regurgitation incidence was higher in raphe(+) group than in raphe(-) group (61.5%(67/109) vs. 22.7%(20/88), P<0.001). Incidence of type 1 of aortic root dilation was higher in raphe(+) group than in raphe(-) group (23.9%(26/109)vs.10.2%(9/88), P=0.024). (2) Aortic stenosis incidence was lower in L-R group than in L/R-N group(29.6%(37/125) vs. 68.1%(49/72), P<0.001). Aortic regurgitation incidence was higher in L-R group than in L/R-N group (59.2%(74/125) vs. 18.1%(13/72), P<0.001). Incidence of type 3 of aortic root dilation was lower in L-R group than in L/R-N group(10.4%(13/125) vs. 37.5%(27/72), P=0.006). (3) Aortic stenosis incidence was lower in L-R patients than in L/R-N patients(15.1%(13/86)vs. 52.2%(12/23), P=0.001), and aortic regurgitation incidence was higher in L-R patients than in L/R-N patients in raphe(+) group(73.3%(63/86)vs. 17.4%(4/23), P<0.001). Conclusion: There is significant difference in the type of valvular dysfunction and ascending aorta dilatation in patients with different morphological characteristics of BAV.


Subject(s)
Aortic Valve Insufficiency , Aortic Valve Stenosis , Aortic Valve/abnormalities , Heart Valve Diseases , Heart Valve Prosthesis , Aorta , Aortic Diseases , Bicuspid Aortic Valve Disease , Dilatation, Pathologic , Humans , Incidence , Retrospective Studies
16.
Phys Rev E ; 95(2-1): 022214, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28297938

ABSTRACT

The trajectory equations for classical periodic orbits in the equilateral-triangular and circular billiards are systematically extracted from quantum stationary coherent states. The relationship between the phase factors of quantum stationary coherent states and the initial positions of classical periodic orbits is analytically derived. In addition, the stationary coherent states with noncoprime parametric numbers are shown to correspond to the multiple periodic orbits, which cannot be explicable in the one-particle picture. The stationary coherent states are further verified to be linked to the resonant modes that are generally observed in the experimental wave system excited by a localized and unidirectional source. The excellent agreement between the resonant modes and the stationary coherent states not only manifests the importance of classical features in experimental systems but also paves the way to manipulate the mesoscopic wave functions localized on the periodic orbits for applications.

17.
Phys Rev E ; 95(1-1): 012217, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28208465

ABSTRACT

A general method is developed to characterize the family of classical periodic orbits from the quantum Green's function for the two-dimensional (2D) integrable systems. A decomposing formula related to the beta function is derived to link the quantum Green's function with the individual classical periodic orbits. The practicality of the developed formula is demonstrated by numerically analyzing the 2D commensurate harmonic oscillators and integrable quantum billiards. Numerical analyses reveal that the emergence of the classical features in quantum Green's functions principally comes from the superposition of the degenerate states for 2D harmonic oscillators. On the other hand, the damping factor in quantum Green's functions plays a critical role to display the classical features in mesoscopic regime for integrable quantum billiards, where the physical function of the damping factor is to lead to the coherent superposition of the nearly degenerate eigenstates.

18.
Clin Genet ; 92(4): 397-404, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28170089

ABSTRACT

BACKGROUND AND AIMS: Mutations in the disheveled, Egl-10 and pleckstrin domain-containing protein 5 (DEPDC5) gene have emerged as an important cause of various familial focal epilepsy syndromes. However, the significance of DEPDC5 mutations in patients with sporadic focal epilepsy has yet to be characterized. MATERIALS AND METHODS: We studied a kindred of familial focal epilepsy with variable foci using whole-exome sequencing. We subsequently studied a cohort of 293 patients with focal epilepsy and sequenced all exons of DEPDC5 using targeted resequencing. RESULTS: We reported a Taiwanese family with a novel splice site mutation which affected mRNA splicing and activated the downstream mammalian target of rapamycin (mTOR) pathway. Among patients with focal epilepsies, the majority (220/293) of these patients had sporadic focal epilepsy without malformation of cortical development. Two (0.9%) of these patients had probably pathogenic mutations in the DEPDC5 gene. DISCUSSION AND CONCLUSIONS: Our finding suggests that DEPDC5 is not only the most common gene for familial focal epilepsy but also could be a significant gene for sporadic focal epilepsy. Since focal epilepsies account for more than 60% of all epilepsies, the effect of mTORC1 inhibitor on patients with focal epilepsy due to DEPDC5 mutations will be an important future direction of research.


Subject(s)
Epilepsies, Partial/genetics , Genetic Predisposition to Disease , Repressor Proteins/genetics , TOR Serine-Threonine Kinases/genetics , Adolescent , Child , Child, Preschool , Epilepsies, Partial/pathology , Female , GTPase-Activating Proteins , Humans , Male , Mechanistic Target of Rapamycin Complex 1/genetics , Mutation , Pedigree , RNA Splicing/genetics , Exome Sequencing
19.
Opt Express ; 24(1): 82-91, 2016 Jan 11.
Article in English | MEDLINE | ID: mdl-26832239

ABSTRACT

Broad-area vertical-cavity surface-emitting lasers (VCSELs) with different cavity sizes are experimentally exploited to manifest the influence of the finite confinement strength on the path-length distribution of quantum billiards. The subthreshold emission spectra of VCSELs are measured to obtain the path-length distributions by using the Fourier transform. It is verified that the number of the resonant peaks in the path-length distribution decreases with decreasing the confinement strength. Theoretical analyses for finite-potential quantum billiards are numerically performed to confirm that the mesoscopic phenomena of quantum billiards with finite confinement strength can be analogously revealed by using broad-area VCSELs.

20.
J Acoust Soc Am ; 137(4): 2113-23, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25920861

ABSTRACT

The Chladni nodal line patterns and resonant frequencies for a thin plate excited by an electronically controlled mechanical oscillator are experimentally measured. Experimental results reveal that the resonant frequencies can be fairly obtained by means of probing the variation of the effective impedance of the exciter with and without the thin plate. The influence of the extra mass from the central exciter is confirmed to be insignificant in measuring the resonant frequencies of the present system. In the theoretical aspect, the inhomogeneous Helmholtz equation is exploited to derive the response function as a function of the driving wave number for reconstructing experimental Chladni patterns. The resonant wave numbers are theoretically identified with the maximum coupling efficiency as well as the maximum entropy principle. Substituting the theoretical resonant wave numbers into the derived response function, all experimental Chladni patterns can be excellently reconstructed. More importantly, the dispersion relationship for the flexural wave of the vibrating plate can be determined with the experimental resonant frequencies and the theoretical resonant wave numbers. The determined dispersion relationship is confirmed to agree very well with the formula of the Kirchhoff-Love plate theory.

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