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1.
Rev Sci Instrum ; 95(5)2024 May 01.
Article in English | MEDLINE | ID: mdl-38739425

ABSTRACT

Correlation-based detection techniques are widely used in the weak periodic signal detection field. Traditionally, they are based on extracting the correlation of a weak signal from noise. Considering the impact of a weak signal on the randomness of background noise, this article takes the opposite approach and proposes a weak signal detection technique based on the Durbin-Watson (DW) test and one-bit sampling, detecting the weak signal due to the extent to which the randomness of noise is affected. The randomness of noise is analyzed through the DW test, which is a method for detecting the randomness of data sequences through first-order autocorrelation. One-bit sampling is adopted to reduce the complexity of the sampling circuit and data processing algorithm. The effectiveness of the DW test in the situation of one-bit sampling is demonstrated through simulation and analysis. Simulation results show that the proposed technique is capable of detecting weak sinusoidal and square-wave signals with a signal-to-noise ratio (SNR) above -30 dB, and the frequency or SNR of a weak signal can be further estimated based on mutual constraints. The measured results confirm the capability. In addition, the factors of coherent sampling, noise bandwidth, and comparator threshold that influence the performance of the proposed technique are simulated and discussed in detail.

2.
Heliyon ; 10(8): e28831, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38638998

ABSTRACT

Objective: To evaluate the effectiveness of different acupuncture treatments for mammary gland hyperplasia (MGH) using a network meta-analysis. Methods: Several databases were searched without language restrictions from 2000 to February 2023, including PubMed, Embase, Web of Science, Cochrane Library, China Science and Technology Journal Database, China Biology Medicine Database, Wanfang Database, China National Knowledge Infrastructure Database, and other professional websites and gray literature. Inclusion criteria were adult women diagnosed with MGH; intervention measures included acupuncture and related therapies; the control group was treated with simple drugs; and the research type was a randomized controlled trial (RCT). The primary outcomes were treatment effectiveness and estradiol and progesterone levels. Secondary outcomes were breast lump size and visual analog scale (VAS) score of breast pain. Exclusion criteria were studies unrelated to MGH, incorrect study populations, control measures or interventions, incomplete data, non-RCTs, case reports, and animal experiments. Cochrane tools were used to assess the risk of bias. The R software (x64 version 4.2.1), Review Manager 5.3 software and STATA 16.0 software were used for data analysis. Results: Following a rigorous screening process, data extraction, and quality assessment, 48 eligible RCTs encompassing 4,500 patients with MGH and 16 interventions were included. The results indicated that acupuncture, alone or in combination with traditional Chinese or Western medicine, had better therapeutic effects than conventional therapy. In terms of effectiveness, warm needle acupuncture was the best choice (94.6%). Bloodletting pricking was the most effective method (85.7%) for lowering progesterone levels. Bloodletting pricking was the most effective method (98.3%) for lowering estradiol levels. Manual acupuncture combined with traditional Chinese medicine was the most effective (74.5%) treatment to improve the size of the breast lump. Warm needle acupuncture was the most effective (69.8%) in improving the VAS score. Conclusion: Acupuncture therapy was more effective in treating MGH than drug therapy alone, and warm needle acupuncture and bloodletting pricking were the two best options. However, larger sample sizes and high-quality RCTs are required.

3.
Bioorg Med Chem Lett ; 99: 129598, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38169246

ABSTRACT

The synthesis of compounds based on fragments derived from natural products (NPs) serves as a source of inspiration for the design of pseudo-natural products (PNPs), to identify bioactive molecules that exhibit similar characteristics to NPs. These novel molecular scaffolds exhibit previously unexplored biological activities as well. This study reports the development and synthesis of a novel pentacyclic ring system, the indole-pyrimidine-quinoline (IPQ) scaffold. The design of this scaffold was based on the structural characteristics of four natural products, namely tryptanthrin, luotonin A, rutaecarpine, and camptothecin. Several successive steps accomplished the effective synthesis of the IPQ scaffold. The constituent components of the pentacycle, containing the indole, quinazolinone, pyrimidone, and quinoline units, possess significant biological significance. Compound 1a demonstrated noteworthy anti-tumor activity efficacy against A549 cell lines among the tested compounds. The compound 1a was observed to elicit cell cycle arrest in both the G2/M and S phases, as well as trigger apoptosis in A549 cells. These effects were attributed to its ability to modulate the activation of mitochondrial-related mitogen-activated protein kinase (MAPK) signaling pathways.


Subject(s)
Antineoplastic Agents , Biological Products , Quinolines , Antineoplastic Agents/chemistry , Apoptosis , Biological Products/pharmacology , Biological Products/chemistry , Camptothecin/pharmacology , Cell Cycle Checkpoints , Cell Line, Tumor , Quinolines/pharmacology , Indoles/chemistry , Indoles/pharmacology , Pyrimidines
4.
Heliyon ; 9(8): e18374, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37520978

ABSTRACT

The beam spreading and evolution behavior of a partially coherent, Hermite-cosine-Gaussian (HcosG) rectangular multi-Gaussian correlated Schell-model beam propagating in oceanic turbulence is studied. Analytical expressions for the cross-spectral density function, as well as the root mean square (rms) beam width and the spectral degree of coherence, are derived based on the extended Huygens-Fresnel principle. The HcosG rectangular multi-Gaussian correlated Schell-model beam exhibits a multi-lobe pattern at short propagation distances. The dependencies of the number, size, shape, and centroid of the lobes on displacement parameters, source size, order of field distribution, and displacement are investigated. As the propagation distance increases, the spectral coherence decreases, and the differences between the spectral coherence curves gradually diminish. Additionally, for HcosG rectangular multi-Gaussian correlated Schell-model beams, better propagation performance was found in oceanic turbulence with larger mean square temperature dissipation rate, smaller turbulent kinetic energy dissipation rate per unit mass of fluid, and larger relative strength of temperature and salinity fluctuation.

5.
Heliyon ; 9(2): e13501, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36846667

ABSTRACT

The beam spreading, spectral degree of coherence and evolution behavior of the intensity profile of partially coherent Lorentz-Gaussian elliptical multi-Gaussian correlation Schell-Model beam propagating in anisotropic atmospheric turbulence are studied. The analytical expressions of cross-spectral density function, as well as root mean square (rms) beam width, are derived based on the extended Huygens-Fresnel principle and the relationship of Lorentz distribution and Hermitian Gaussian function. With the increases of propagation distance, the elliptical beam will first evolve into Gaussian beam and then change back to elliptical beam. In anisotropic atmospheric turbulence, the influence of the inner scale of turbulence on the spectral degree of coherence and rms beam width are obviously greater than that of the outer scale. For Lorentz-Gaussian elliptical multi-Gaussian correlated Schell-Model beams, better propagation performance was found in anisotropic atmospheric turbulence with larger anisotropic factor and smaller inner scale.

6.
Front Endocrinol (Lausanne) ; 13: 1074516, 2022.
Article in English | MEDLINE | ID: mdl-36465626

ABSTRACT

Background: Acupuncture is a widely practiced, convenient, and safe treatment modality within complementary and integrative medicine. Increasing studies have revealed the efficacy of acupuncture for the treatment of osteoporosis in both human and non-human subjects. The aim of the present study was to assess the improvement of osteoporosis after overall adjustment acupuncture (OA) as well as its endocrine-modulating effect in an ovariectomized rat model. Methods: In total, 32 female Sprague-Dawley (SD) rats were randomly divided into the sham, model, ovariectomy+estrogen (OVX+E), and OVX+OA (OVX+A) groups with eight rats in each group. The postmenopausal osteoporosis (PMOP) rat model was induced by bilateral ovariectomy. At 12 weeks after surgery, rats in the OVX+E group received estradiol (0.2 mg/kg/i.g./qod) for 12 weeks, and rats in the OVX+A group were treated with acupuncture at Zusanli (ST36), Shenshu (BL23), and Dazhu (BL11) points (qod) for 12 weeks. At the end of the treatment, all rats were sacrificed, and the body weight, uterus index, bone mineral density (BMD), bone mineral content (BMC), bone trabeculae structural parameters, femoral biomechanical properties, femoral histomorphology, and several hormone levels were examined. Results: In OVX rats, OA abrogated the body weight gain and improved osteoporosis in terms of BMD, BMC, bone trabeculae structural parameters, bone strength, and bone tissue histomorphology. Moreover, OA modulated the serum levels of estradiol, corticotropin releasing hormone (CRH), adrenocorticotropic hormone (ACTH), and corticosterone (CORT). Conclusions: OA improves osteoporosis and exerts an endocrine-modulating effect in ovariectomized rats.


Subject(s)
Acupuncture Therapy , Osteoporosis , Female , Rats , Animals , Humans , Rats, Sprague-Dawley , Osteoporosis/therapy , Estradiol , Estrogens , Body Weight
7.
Front Pharmacol ; 13: 922477, 2022.
Article in English | MEDLINE | ID: mdl-36188592

ABSTRACT

It is estimated that non-small-cell lung cancer (NSCLC) is responsible for 80% of human deaths related to lung cancer worldwide. Currently, it has been discovered that two transcription factors. Nuclear factor-κB (NF-κB) and Signal transducer and activator of transcription 3 (STAT3) were the main factors affecting inflammation and cancer, and their activation promoted lung cancer cell proliferation. Hedyotis diffusa Willd. (H. diffusa) is an herbal Chinese medicine, which has always been used for the treatment of malignant tumors in clinical. Previous research found that H. diffusa could inhibit the proliferation of H1975 cells, but the specific mechanisms remain elusive. We investigated the effects of total triterpenes extracted from H. diffusa (TTH) on the migration, proliferation and apoptosis of H1975 cells. Cell-cycle and immunofluorescence analysis showed that TTH could block H1975 cells at G0/G1 phase and induce apoptosis of experimental cells. The protein levels of Bcl-2 were decreased, while the levels of pro-apoptotic Bax were increased. In addition, TTH could also inhibit the migration of H1975 cells through downregulated MMP-2 and MMP-9 and upregulated TIMP-2. Further research found that the level of phospho-STAT3 was significantly decreased after administration of TTH. And protein expression level of NF-κB in nucleus was decreased after TTH treatment, while NF-κB in cytoplasm increased. These results suggested that TTH could inhibit the proliferation and migration of H1975 cells, and also could induce cell apoptosis. These effects were closely connected to the activation of NF-κB and the phosphorylation of STAT3.

8.
Heliyon ; 8(9): e10530, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36132177

ABSTRACT

During the operation of the magnetically gain-switched chemical oxygen-iodine laser (MGS-COIL), the transition intensity of hyperfine transition line 2-2 can exceed that of line 3-4, which is the dominant line at zero magnetic field. For this reason, a simulation model including both 3-4 and 2-2 transition lines is necessary to describe the mode buildup process in MGS-COIL. In this paper, we assume that 3-4 and 2-2 transition lines simultaneously oscillate in laser cavity. The propagation of optical field is calculated based on FFT. The required frequency, rise time and residual field of the magnetic gain-switch for a high-performance MGS-COIL are analyzed based on simulation results.

9.
J Med Food ; 25(8): 853-862, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35980327

ABSTRACT

Baicalin and berberine hydrochloride are the main chemical compositions of Scutellariae Radix and Coptidis Rhizoma, respectively. S. Radix and C. Rhizoma are two traditional Chinese herbs that are commonly used together in compounded formulations to treat colitis. Therefore, the combination of Baicalin and berberine hydrochloride (BBH) to treat colitis was studied. The results of pharmacological evaluations demonstrated the excellent protective effects of BBH on colitis induced by dextran sulfate sodium (DSS). BBH could improve the morphological condition of colitis in mice and maintain the balance of proinflammation cytokines (IL-6, IL-8, IL-1ß, and TNF-α) and anti-inflammation cytokines (IL-4 and IL-10). The 16s rDNA sequencing revealed that BBH was able to modulate the composition of intestinal microflora, especially the abundances of Eubacterium_brachy_group, Holdemania, Erysipelotrichaceae_UCG_003, Christensenellaceae_R-7_group, and Sellimonas. The results of PICRUSt indicated that the therapeutic effects of BBH were tightly connected with DNA synthesis, replication and repair of gut microbiota. In summary, it was concluded that BBH could protect mice against DSS-induced colitis, and the protective effects were tightly correlated with gut microbiota.


Subject(s)
Berberine , Colitis, Ulcerative , Colitis , Gastrointestinal Microbiome , Animals , Berberine/pharmacology , Berberine/therapeutic use , Colitis/chemically induced , Colitis/drug therapy , Colitis, Ulcerative/chemically induced , Colon , Cytokines/genetics , Dextran Sulfate/adverse effects , Disease Models, Animal , Flavonoids , Mice , Mice, Inbred C57BL
10.
Opt Express ; 30(3): 3654-3664, 2022 Jan 31.
Article in English | MEDLINE | ID: mdl-35209619

ABSTRACT

Observation of a melting layer using a 1.55 µm coherent Doppler lidar (CDL) is first presented during a stratiform precipitation event. Simultaneous radar measurements are also performed by co-located 1.24 cm micro rain radar (MRR) and 10.6 cm Doppler weather radar (DWR). As a well-known bright band in radar reflectivity appears during precipitation, an interesting dark band about 160 m below that in lidar backscattering is observed. Due to the absorption effect, the backscattering from raindrops at 1.55 µm is found much weaker than that at short wavelengths usually used in direct detection lidars. However, the CDL provides additional Doppler information which is helpful for melting layer identification. For example, a spectrum bright band with broadened width and sign conversion of skewness is detected in this case. After a deep analysis of the power spectra, the aerosol and precipitation components are separated. The fall speed of hydrometeors given by CDL is found smaller than that of MRR, with the differences of approximately 0.5 m/s and 1.5 m/s for the snow and rainfall, respectively. To illustrate the influence of absorption effect, simulations of the backscatter coefficient and extinction coefficient of aerosol and rainfall are also performed at the wavelength range of 0.3 ∼ 2.2 µm using the Mie theory.

11.
Medicine (Baltimore) ; 100(34): e27033, 2021 Aug 27.
Article in English | MEDLINE | ID: mdl-34449482

ABSTRACT

BACKGROUND: Attention Deficit Hyperactivity Disorder (ADHD) is the most common behavioral disorder in childhood. Acupuncture treatment of ADHD has formed a relatively systematic theoretical and clinical treatment system which achieved satisfactory results. However, there has been no systematic evaluation of its effectiveness and safety. The purpose of this study was to evaluate the efficacy and safety of acupuncture in the treatment of ADHD. METHODS: A systematic search of literature will be conducted in PubMed, Cochrane Library, the Web of Science, Excerpt Medica Database, Chinese Biomedical Literature Database, VIP, Wanfang database, China National Knowledge Infrastructure database for articles published up to September, 2019. The searching terms include "attention deficit", "hyperactivity", "mild brain dysfunction", "acupuncture", "electroacupuncture". The search is limited to studies published in Chinese and English. Two reviewers will extract and evaluate the information independently. Cochrane Collaboration tool and Jadad scale will be used to evaluate the quality of the studies. Review Manager Version 5.3 (Cochrane Collaboration's software) will be used to carry out the meta-analysis. RESULTS: High-quality synthesis and/or descriptive analysis of current evidence will be provided from effective rate, total score of traditional Chinese medicines syndromes, conners child hyperactivity-diagnosis rating scale, conners index of hyperactivity, the recurrence rate, and adverse events. CONCLUSION: This study will provide the evidence of whether acupuncture is an effective and safe intervention to ADHD. INPLASY REGISTRATION NUMBER: INPLASY202140022.


Subject(s)
Acupuncture Therapy/methods , Attention Deficit Disorder with Hyperactivity/therapy , Clinical Trials as Topic , Humans , Research Design , Meta-Analysis as Topic
12.
Opt Express ; 26(23): 30061-30075, 2018 Nov 12.
Article in English | MEDLINE | ID: mdl-30469886

ABSTRACT

The beam spreading and evolution behavior of the intensity profile and coherent vortices of partially coherent, four-petal elliptic Gaussian vortex beams propagating in atmospheric turbulence are studied. The analytical expressions for cross-spectral density function, as well as root mean square (rms) beam width, are derived based on the extended Huygens-Fresnel principle. Results showed that, unlike the partially coherent four-petal Gaussian vortex beams, the partially coherent four-petal elliptic Gaussian vortex beam could change its petal number into six. The dependencies of occurrence, appearance, and transition speed from four- to six-petal profile on the topological charge, the beam order, and the ellipticity factor are illustrated. The far field behaviors of partially coherent four-petal elliptic Gaussian vortex beams propagating in atmospheric turbulence and are compared in free space. Beams with larger topological charge, smaller beam order, and larger ellipticity factor were found to be less influenced by atmospheric turbulence. Further, the ellipticity factor can be used as an additional degree of freedom in controlling the conservation distance of coherence vortices' topological charge.

13.
Opt Express ; 23(3): 2933-44, 2015 Feb 09.
Article in English | MEDLINE | ID: mdl-25836154

ABSTRACT

The multi-perturbation stochastic parallel gradient descent (SPGD) method for adaptive optics is presented in this work. The method is based on a new architecture. The incoming beam with distorted wavefront is split into N sub-beams. Each sub-beam is modulated by a wavefront corrector and its performance metric is measured subsequently. Adaptive system based on the multi-perturbation SPGD can operate in two modes - the fast descent mode and the modal basis updating mode. Control methods of the two operation modes are given. Experiments were carried out to prove the effectiveness of the proposed method. Analysis as well as experimental results showed that the two operation modes of the multi-perturbation SPGD enhance the conventional SPGD in different ways. The fast descent mode provides faster convergence than the conventional SPGD. The modal basis updating mode can optimize the modal basis set for SPGD with global coupling.

14.
Opt Express ; 19(27): 26295-307, 2011 Dec 19.
Article in English | MEDLINE | ID: mdl-22274214

ABSTRACT

Coupled simulation based on intracavity partially coherent light model and 3D CFD model is firstly achieved in this paper. The dynamic equation of partially coherent intracavity field is derived based on partially coherent light theory. A numerical scheme for the coupled simulation as well as a method for computing the intracavity partially coherent field is given. The presented model explains the formation of the sugar scooping phenomenon, and enables studies on the dependence of the spatial mode spectrum on physical parameters of laser cavity and gain medium. Computational results show that as the flow rate of iodine increases, higher order mode components dominate in the partially coherent field. Results obtained by the proposed model are in good agreement with experimental results.


Subject(s)
Computer-Aided Design , Gases/chemistry , Lasers , Microfluidics/methods , Models, Theoretical , Computer Simulation , Equipment Design , Equipment Failure Analysis , Light , Scattering, Radiation
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