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1.
Heliyon ; 10(11): e31928, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38868063

ABSTRACT

Objective: The objective is to construct a random forest model for predicting the occurrence of Myofascial pelvic pain syndrome (MPPS) and compare its performance with a logistic regression model to demonstrate the superiority of the random forest model. Methods: We retrospectively analyze the clinical data of female patients who underwent pelvic floor screening due to chronic pelvic pain at the Pelvic Floor Rehabilitation Center of the Third Affiliated Hospital of Zhengzhou University from January 2021 to December 2023. A total of 543 female patients meeting the study's inclusion and exclusion criteria are randomly selected from this dataset and allocated to the MPPS group. Furthermore, 702 healthy female patients who underwent pelvic floor screening during routine physical examinations within the same timeframe are randomly selected and assigned to the non-MPPS group. Chi-square test and rank-sum test are used to select demographic variables, pelvic floor pressure assessment data variables, and modified Oxford muscle strength grading data for logistic univariate analysis. The selected variables are further subjected to multivariate logistic regression analysis, and a random forest model is also established. The predictive performance of the two models is evaluated by comparing their accuracy, sensitivity, specificity, precision, receiver operating characteristic (ROC) curve, and area under the curve (AUC) area. Results: Based on a dataset of 1245 cases, we implement the random forest algorithm for the first time in the screening of MPPS. In this investigation, the Logistic regression model forecasts the accuracy, sensitivity, specificity, and precision of MPPS at 69.96 %, 57.46 %, 79.63 %, and 68.57 % respectively, with an AUC of the ROC curve at 0.755. Conversely, the random forest prediction model exhibits accuracy, sensitivity, specificity, and precision rates of 87.11 %, 90.66 %, 90.91 %, and 83.51 % respectively, with an AUC of the ROC curve at 0.942. The random forest model showcases exceptional predictive performance during the initial screening of MPPS. Conclusion: The random forest model has exhibited exceptional predictive performance in the initial screening evaluation of MPPS disease. The development of this predictive framework holds significant importance in refining the precision of MPPS prediction within clinical environments and elevating treatment outcomes. This research carries profound global implications, given the potentially elevated misdiagnosis rates and delayed diagnosis proportions of MPPS on a worldwide scale, coupled with a potential scarcity of seasoned healthcare providers. Moving forward, continual refinement and validation of the model will be imperative to further augment the precision of MPPS risk assessment, thereby furnishing clinicians with more dependable decision-making support in clinical practice.

2.
Opt Express ; 32(6): 8723-8735, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38571123

ABSTRACT

In this study, a Si defect structure was added into the silica network in order to activate the bismuth and silica structure active center. TD-DFT theoretical simulations show that the Bi and Si ODC(I) models can excite the active center of the E-band at 1408 nm. Additionally, the Bi-doped silica fiber (BDSF) with improved fluorescence was fabricated using atomic layer deposition (ALD) combined with the modified chemical vapor deposition (MCVD) technique. Some tests were used to investigate the structural and optical properties of BDSF. The UV-VIS spectral peak of the BDSF preform is 424 cm-1, and the binding energy of XPS is 439.3 eV, indicating the presence of Bi° atom in BDSF. The Raman peak near 811 cm-1 corresponds to the Bi-O bond. The Si POL defect lacks a Bi-O structure, and the reason for the absence of simulated active center from the E-band is explained. A fluorescence spectrometer was used to analyze the emission peak of a BDSF at 1420 nm. The gain of the BDSF based optical amplifier was measured 28.8 dB at 1420 nm and confirmed the effective stimulation of the bismuth active center in the E-band.

3.
Opt Express ; 32(6): 8937-8949, 2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38571139

ABSTRACT

In this study, PbS/Er co-doped fibers (PEDFs) were fabricated by atomic layer deposition (ALD) combined with modified chemical vapor deposition (MCVD). A pumping scheme based on two-photon absorption at 1310 nm of PEDF is proposed for L + band amplification. Through the theoretical analysis, the local environment of Er3+ is changed due to the co-doping of PbS, which improves the two-photon absorption efficiency near 1300 nm. Compared with the 980 nm pump, the PEDFs excited by the 1310 nm pump show better amplification performance in the L + band. And in a bi-directional pumping system, PEDF achieves over 22 dB of gain in the whole L band. In particular, the bandwidth of over 20 dB gain was extended to 1627 nm with a noise figure as low as 4.9 dB. To the best of our knowledge, this is the first time that a high-gain bandwidth of L band amplification has been extended to 1627 nm. The results of unsaturated loss also show that PbS co-doping improves the two-photon absorption efficiency of PEDF to broaden the amplification bandwidth of L + band. These results demonstrate that an effective L + band amplification method is practically provided for future ultra-wideband optical communications.

4.
J Clin Ultrasound ; 52(4): 473-477, 2024 May.
Article in English | MEDLINE | ID: mdl-38288546

ABSTRACT

A rare case of unicornuate uterus with interstitial ectopic pregnancy was diagnosed using three-dimensional transvaginal ultrasound (3D-TVUS). The ultrasound revealed a "lancet-shaped" endometrial corona, a gestational sac near the uterus base extending toward the uterine serosa, and visible interstitial lines. The patient underwent laparoscopic surgery for a lesion in the right fallopian tube. 3D-TVUS was crucial in precisely locating the gestational sac, aiding in effective treatment. Interstitial ectopic pregnancies risk severe hemorrhaging upon rupture. Rapid, accurate diagnosis is vital for lifesaving treatment and preventing critical complications.


Subject(s)
Imaging, Three-Dimensional , Pregnancy, Interstitial , Uterus , Uterus/abnormalities , Humans , Female , Pregnancy , Uterus/diagnostic imaging , Uterus/surgery , Imaging, Three-Dimensional/methods , Adult , Pregnancy, Interstitial/diagnostic imaging , Pregnancy, Interstitial/surgery , Urogenital Abnormalities/diagnostic imaging , Urogenital Abnormalities/surgery , Urogenital Abnormalities/complications , Ultrasonography, Prenatal/methods , Laparoscopy/methods
5.
Oral Dis ; 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38191959

ABSTRACT

BACKGROUND: Temporomandibular joint disorders (TMDs) are common in young adults, and the link between chronotype profile and TMDs is unclear. OBJECTIVE: This study examined TMD prevalence and chronotype distribution and explored the relationship between chronotype and TMDs in young adults. MATERIALS AND METHODS: A total of 663 students from Sichuan University completed questionnaires. Chronotype profiles were assessed using the Morningness-Eveningness Questionnaire, and TMDs were screened using the Fonseca Memory Index. To validate the findings, 68 TMD patients and 136 controls were enrolled. RESULTS: The prevalence of TMDs was 69.7%, with significant differences among chronotype profiles. The intermediate profile was the most common chronotype. Eveningness profile was associated with higher TMDs prevalence and severity. Muscle pain and side movement difficulty scores were higher in eveningness and intermediate profiles. Female gender (OR 2.345; 95% CI 1.668-3.297) was a TMD risk factor, while morningness profile (OR 0.537; 95% CI 0.297-0.970) was protective. Validation with TMD patients and controls supported these findings, showing higher eveningness profile prevalence in the TMD groups. CONCLUSIONS: TMDs have a high prevalence in college students, chronotype profiles shown to be associated with TMDs. Morningness is the protection factor in TMDs and PT, eveningness is a risk factor for IT.

6.
Appl Opt ; 62(25): 6809-6815, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37706815

ABSTRACT

An extrinsic fiber optic Fabry-Perot interferometric (EFPI) ultrasonic sensor based on a grooved silicon diaphragm for partial discharge (PD) detection has been proposed. The size of the groove is determined by finite element simulation, which allows the resonant frequency of the sensor to meet the requirements of PD ultrasonic detection and improves the sensitivity of the sensor by 5.07 times compared with that based on a traditional circular diaphragm. The microelectro-mechanical system process is used to fabricate the diaphragm on a silicon-on-insulator wafer, and the prepared diaphragm has a grooved section with a diameter of 829.34 µm and a thickness of only 2.09 µm. At its resonant frequency of 61.5 kHz, the acoustic pressure sensitivity of the sensor is 172.42 mV/Pa. The ultrasonic signal detection capability of the sensor is verified in the PD experiment. Furthermore, the characteristics of the corona discharge are successfully manifested based on the ultrasonic waves detected by the EFPI sensor. It is demonstrated that the proposed sensor is suitable for PD detection due to its high sensitivity, simple production process, and good resistance to environmental interference.

7.
Opt Express ; 31(9): 14862-14872, 2023 Apr 24.
Article in English | MEDLINE | ID: mdl-37157341

ABSTRACT

In this work, bismuth doped fiber (BDF) and bismuth/phosphosilicate co-doped fiber (BPDF) were fabricated by atomic layer deposition (ALD) combined with the modified chemical vapor deposition (MCVD). The spectral characteristics are studied experimentally and the BPDF has good excitation effect covering the O band. A diode pumped BPDF amplifier with the gain over 20 dB from 1298-1348 nm (50 nm) has been demonstrated. The maximum gain of 30 dB was measured at 1320 nm with a gain coefficient of around 0.5 dB/m. Furthermore, we constructed different local structures through simulation and found that compared with the BDF, BPDF has a stronger excited state and a greater significance in O-band. This is mainly because phosphorus (P) doping changes the associated electron distribution and forms the bismuth-phosphorus active center. The fiber has a high gain coefficient, which is of great significance for the industrialization of O-band fiber amplifier.

8.
BMC Neurol ; 23(1): 83, 2023 Feb 27.
Article in English | MEDLINE | ID: mdl-36849878

ABSTRACT

OBJECTIVES: This study aimed to assess the epidemiological features and explore the potential risk factors for early neurological deterioration (END) in patients with acute single small subcortical infarction (SSSI) who underwent antiplatelet therapy without carotid artery stenosis. MATERIALS & METHODS: Patients with SSSI, as confirmed by cranial magnetic resonance imaging (MRI), who were hospitalized within 48 h after the onset of symptoms were enrolled. END was mainly defined as increment in the National Institutes of Health Stroke Scale (NIHSS) score of ≥ 2 points or any new neurological deficit. Poor functional outcome was defined as modified Rankin Scale (mRS) score of > 2 points at 3-month after the onset. The association of END with multiple indicators was assessed at the early stage of admission using multivariate logistic regression analysis, and adjusted odds ratios (aORs) were calculated. RESULTS: A total of 280 patients were enrolled from June 2020 to May 2021, of whom, END occurred in 44 (15.7%) patients (median age, 64 years; 70.5% male), while END occurred during sleep in 28 (63.6%) patients. History of hypertension (aOR: 4.82, p = 0.001), infarction in internal capsule (aOR: 3.35, p = 0.001), and elevated level of low-density lipoprotein cholesterol (LDL-C; aOR: 0.036, p = 0.0016) were significantly associated with the risk of END. Patients with END (aOR: 5.74, p = 0.002), history of diabetes (aOR: 2.61, p = 0.020), and higher NIHSS scores at discharge (per 1-score increase, aOR: 1.29, p = 0.026) were associated with the poor functional outcome at 3-month after the onset. CONCLUSION: Patients with a history of hypertension, infarction in internal capsule or a higher level of LDL-C were found to be at a higher risk of END.


Subject(s)
Cerebral Infarction , Hypertension , United States , Humans , Male , Middle Aged , Female , Cholesterol, LDL , Constriction, Pathologic , Risk Factors , Cerebral Infarction/diagnostic imaging , Cerebral Infarction/epidemiology , Hypertension/complications , Hypertension/epidemiology , Arteries
9.
ACS Sens ; 8(1): 133-140, 2023 01 27.
Article in English | MEDLINE | ID: mdl-36630575

ABSTRACT

Rapid and efficient detection and identification of proteins hold great promise in medical diagnostics, treatment of different diseases, and proteomics. Here, we present a simple colorimetric sensor array for the differentiation of proteins in various osmolyte solutions. Osmolytes have different influences on the conformation of proteins, which have differential binding to silver nanoparticles, resulting in color changes. The sensor array shows unique color change patterns for each of the 19 proteins, allowing unambiguous identification. Very interestingly, the differentiation of 19 proteins is related to their molecular weight. Moreover, the sensor array can be used to identify protein mixtures, thermal denaturized proteins, and unknown protein samples. Finally, the sensor array can also analyze the plasma or liver samples of the four groups of salt-sensitive rats fed with different diets, indicating that it has the potential for the classification of metabolic profiles.


Subject(s)
Metal Nanoparticles , Animals , Rats , Metal Nanoparticles/chemistry , Colorimetry/methods , Silver/chemistry , Proteins , Metabolome
10.
Nat Commun ; 13(1): 7732, 2022 12 13.
Article in English | MEDLINE | ID: mdl-36513638

ABSTRACT

Chromosome segregation is initiated by cohesin degradation, which is driven by anaphase-promoting complex/cyclosome (APC/C). Chromosome cohesin is removed by activated separase, with the degradation of securin and cyclinB1. Dynamin-related protein 1 (DRP1), a component of the mitochondrial fission machinery, is related to cyclin dynamics in mitosis progression. Here, we show that DRP1 is recruited to the kinetochore by centromeric Centromere protein F (CENP-F) after nuclear envelope breakdown in mouse oocytes. Loss of DRP1 during prometaphase leads to premature cohesin degradation and chromosome segregation. Importantly, acute DRP1 depletion activates separase by initiating cyclinB1 and securin degradation during the metaphase-to-anaphase transition. Finally, we demonstrate that DRP1 is bound to APC2 to restrain the E3 ligase activity of APC/C. In conclusion, DRP1 is a CENP-F-dependent atypical spindle assembly checkpoint (SAC) protein that modulates metaphase-to-anaphase transition by controlling APC/C activity during meiosis I in oocytes.


Subject(s)
Chromosome Segregation , Meiosis , Animals , Mice , Anaphase-Promoting Complex-Cyclosome/metabolism , Cell Cycle Proteins/metabolism , Dynamins/metabolism , Kinetochores/metabolism , Oocytes/metabolism , Securin/genetics , Securin/metabolism , Separase/metabolism
11.
Materials (Basel) ; 15(17)2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36079471

ABSTRACT

Er-doped optical fiber (EDF) with ultra-broad gain bandwidth is urgently needed given the rapid advancement of optical communication. However, the weak crystal field of the host silica glass severely restricts the bandwidth of traditional EDF at 1.5 µm. In this study, we theoretically explored the introduction of PbS nanomaterials in the silica network assisted with the non-bridging oxygen. This can significantly increase the crystal field strength of Er3+ ions in the local structure, leading to their energy level splitting and expanding the fluorescence bandwidth. Additionally, the PbS/Er co-doped optical fiber (PEDF) with improved fluorescence and gain characteristics was fabricated using modified chemical vapor deposition combined with the atomic layer deposition technique. The presence of PbS nanomaterials in the fiber core region, which had an average size of 4 nm, causes the 4I13/2 energy level of Er3+ ions to divide, increasing the fluorescence bandwidth from 32 to 39 nm. Notably, the gain bandwidth of PEDF greater than 20 dB increased by approximately 12 nm compared to that of EDF. The obtained PEDF would play an important role in the optical fiber amplifier and laser applications.

12.
Opt Lett ; 47(11): 2766-2769, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35648925

ABSTRACT

We demonstrate a high-sensitivity bidirectional magnetic field sensor based on a packaged optofluidic microbottle resonator (OFMBR) filled with magnetic fluid (MF). The relationship between sensitivity and different wall thicknesses and radial modes of OFMBR is theoretically analyzed. Then the thin-wall OFMBR is fabricated by etching a capillary with the fusion discharge process. The OFMBR and tapered fiber is packaged with a portable and robust coupling configuration. By applying perpendicular or parallel magnetic field directions to the OFMBR, opposite refractive index responses of the MF can be obtained, with resonant wavelengths redshifted or blueshifted as the magnetic field intensity is increased. A magnetic field sensitivity of 98.23 pm/mT can be obtained by using the second-order radial mode when the magnetic field is perpendicular to the packaged OFMBR. When the magnetic field is parallel to the packaged OFMBR, the sensitivity is -304.80 pm/mT by using the third-order radial mode and the detection limit reaches 0.0656 mT. The proposed sensor has the advantages of easy fabrication, high sensitivity, and reliability, showing a great potential in bidirectional magnetic field application.

13.
Opt Express ; 29(21): 34577-34589, 2021 Oct 11.
Article in English | MEDLINE | ID: mdl-34809244

ABSTRACT

The magneto-refractive properties of an erbium-doped fiber (EDF) are investigated by theoretically analyzing the change in mode characteristics with a magnetic field and experimentally measuring it based on a fiber-optic Mach-Zehnder interferometer (MZI). The numerical results indicate that the mode effective refractive index (RI) increases as the magnetic field increases, and the mode field intensity distribution tends to be more concentrated in the core region with an increasing magnetic field. The variation in the mode effective RI of the fundamental mode with the magnetic field is greater than that of the higher-order modes. A magneto-refractive measurement system based on a fiber-optic MZI is set up to analyze the magneto-refractive effect of the EDF. The changes in the mode effective RI measured with a direct-current (DC) magnetic field and with a 100 Hz alternating-current (AC) magnetic field are 4.838×10-6 and 4.245×10-6 RIU/mT, respectively. The experimental results are in reasonable agreement with the theoretical analysis. Furthermore, the error between the experimental and numerical results is discussed. The magneto-refractive properties of the EDF exhibit potential in all-fiber magnetic field or current sensing area.

14.
Colloids Surf B Biointerfaces ; 208: 112112, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34600361

ABSTRACT

Bacterial biofilms are responsible for many chronic infections because antibacterial agents exhibit poor penetration into the dense matrix barrier and cannot easily reach the internal bacteria. Herein, we reported pH-responsive nanocomposites (PDA@Kana-AgNPs) that could penetrate and disperse biofilms, which were synthesized by the combination of ultrasmall silver nanoparticles (AgNPs) and kanamycin, and then coating with polydopamine. Confocal fluorescence imaging indicated that PDA@Kana-AgNPs could respond to the acidic microenvironment of biofilms, leading to biofilm-triggered on- demand drug release in situ. The zone of inhibition test and Resazurin assay showed that the combination of kanamycin and AgNPs had greater antimicrobial activity against test strains (Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Escherichia coli BL21) than when applied separately. The crystal violet staining test demonstrated that biofilms were effectively dispersed by the proposed nanocomposites. Biocompatibility was also evaluated, which showed that PDA@Kana-AgNPs were non-toxic to mammalian cells. Therefore, the proposed pH-responsive nanocomposites held great potential for efficient antibiotics delivery and showed synergistic antibacterial and antibiofilm activities. This strategy could also be used to encapsulate a variety of antibiotics in combination with other drugs or materials, thereby showing therapeutic potential in preventing biofilm-related infections and realizing fluorescence imaging in situ.


Subject(s)
Metal Nanoparticles , Nanocomposites , Aminoglycosides , Animals , Anti-Bacterial Agents/pharmacology , Biofilms , Hydrogen-Ion Concentration , Silver
15.
Opt Express ; 29(20): 32208-32219, 2021 Sep 27.
Article in English | MEDLINE | ID: mdl-34615297

ABSTRACT

A simple and compact magnetic field and temperature dual-parameter sensor is proposed, which is based on a sandwich structure consisting of a section of hollow core Bragg fiber (HCBF) filled with magnetic fluid (MF) and two sections of single-mode fiber (SMF). The corresponding relationship between the resonant dip with different periods in the transmission spectrum and specific anti-resonant (AR) mode in the HCBF is determined. The resonant dips based on different AR modes shift differently when the magnetic field intensity and temperature change. Then, the simultaneous measurement of the magnetic field intensity and temperature can be achieved by utilizing a cross matrix. The experimental results show that the maximum magnetic field sensitivity in the range of 0-12 mT is 86.43 pm/mT, and the maximum temperature sensitivity in the range of 20-60 ℃ is 17.8 pm/℃. The proposed sensor has the advantages of compact structure, easy fabrication and low cost, thus, it has great potential applications in the field of simultaneous sensing of magnetic field intensity and temperature in complex environments.

16.
Anal Bioanal Chem ; 413(18): 4689-4696, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33893514

ABSTRACT

Sensitive and rapid identification of pathogenic microorganisms is of great importance for clinical diagnosis and treatment. In this study, we developed an ultrasensitive colorimetric sensor array (CSA) based on the interactions between aminoglycoside antibiotics (AMGs) and Ag nanoparticles decorated with ß-cyclodextrin (AgNPs@ß-CD) to discriminate microorganisms quickly and accurately. Microorganisms can absorb different amounts of AMGs after incubation. Upon the addition of AgNPs@ß-CD, the corresponding extracellular AMG residues will bind to AgNPs@ß-CD, leading to color changes due to the modifications in localized surface plasmon resonance. The array was developed using 4 AMGs as sensing elements and AgNPs@ß-CD as the colorimetric probe to generate a unique colorimetric response pattern for each microorganism. Standard chemometric methods indicated excellent discrimination among 20 microorganisms at low concentrations of 2 × 106 CFU/mL. Therefore, this ultrasensitive CSA can be used for microbial discrimination portably and efficiently. Importantly, the concentration of microbial discrimination by our array is much lower than that of prior CSAs. This method of extracellular residue sensing also provided a new strategy to improve the sensitivity of conventional CSA in the discrimination of microorganisms, to measure the amount of intercellular uptake of AMGs by microorganisms, and to screen drugs that can easily be accumulated by the pathogenic microorganisms.


Subject(s)
Aminoglycosides/analysis , Drug Residues/analysis , Colorimetry/methods , Humans , Limit of Detection , Metal Nanoparticles/chemistry , Microscopy, Electron, Scanning , Silver/chemistry , Spectrophotometry, Ultraviolet/methods , Surface Plasmon Resonance
17.
J Cell Biochem ; 122(3-4): 442-455, 2021 04.
Article in English | MEDLINE | ID: mdl-33399227

ABSTRACT

As a posttranscriptional regulatory factor, microRNA (miRNA) plays an important role in the formation of myotubes. However, little is known about the mechanism of miRNA regulating myotube morphogenesis. Here, we aimed to characterize the function of miR-455-5p in myotube morphogenesis by inducing differentiation in C2C12 myoblasts containing murine Mylip fragments with the miR-455-5p target sequence. We found that miR-455-5p overexpression promoted the differentiation and hypertrophy of myotubes, while miR-455-5p inhibition led to the failure of myotube differentiation and formation of short myotubes. Furthermore, we demonstrated that miR-455-5p directly targeted the Mylip 3'-untranslated region, which plays a key role in monitoring myotube morphogenesis. Interestingly, the expression and function of Mylip were opposite to those of miR-455-5p during myogenesis. Our data uncovered novel miR-455-5p targets and established a functional link between Mylip and myotube morphogenesis. Understanding the involvement of Mylip in myotube morphogenesis provides insight into the function of the gene regulatory network.


Subject(s)
Cell Differentiation/physiology , MicroRNAs/metabolism , Myoblasts/cytology , Myoblasts/metabolism , Animals , Cell Differentiation/genetics , Cell Proliferation/genetics , Cell Proliferation/physiology , Humans , MicroRNAs/genetics , Muscle Development/genetics , Muscle Development/physiology
18.
J Mol Model ; 26(11): 308, 2020 Oct 21.
Article in English | MEDLINE | ID: mdl-33083942

ABSTRACT

Integrated atomistic and molecular dynamic simulations are used to characterize the role hydrogen bonding and interchain interactions on structures and phase transitions of novel bent-core-like mesogenic materials that exhibit new self-assembly features, attractive to the development of functional materials. Multi-step simulations were carried out to model phase transitions and various spectra of two complex mesogenic materials formed from acid functionalized azo compounds, 4-[2,3,4-tri(octyloxy)phenylazo] benzoic acid and 4-[2,3,4- tri(heptyloxy)phenylazo] benzoic acid. The simulations contain three consecutive steps, involving molecular quantum chemistry, molecular crystal packing, and super cell molecular dynamics calculations. These two mesogens are supposed to form phasmidic molecular conformers. However, simulations point to the formation of complex discotic bent-core-like liquid crystals with tetramer mesogenic assemblies, in very good agreement with experimental observations. The wide range agreements between simulations and experimental results include transitions of crystal structures to columnar and uniaxial nematic phases, x-ray diffraction patterns of columnar phases, the structure of the two-dimensional complex bent-core-like tetramers, molecular Raman spectra, Raman depolarization spectra, and order parameters of nematic phases. The multi-step simulation methodology and its results shed light on this unique behaviour of plasmids with flexible side chains for simulation design of novel bent-core-like mesogenic materials.

19.
Opt Express ; 28(16): 23771-23783, 2020 Aug 03.
Article in English | MEDLINE | ID: mdl-32752369

ABSTRACT

We fabricated a Yb-doped yttrium aluminium garnet (Yb:YAG) crystal-derived silica fiber (YCDSF) using an assembly consisting of a YAG crystal rod and silica tube on a CO2 laser-heated drawing tower. The fiber has a Yb concentration of 5.66 wt%, and absorption coefficient of 32 dB/cm at 980 nm. The figure of merit of the unsaturated absorption and gain per unit length of the YCDSF are 93% and 4.4 dB/cm, respectively. Based on the results of the numerical simulation, an all-fiber distributed Bragg reflector (DBR) laser using only a 1.5-cm-long YCDSF is experimentally demonstrated to have a maximum output power of 360 mW with a pump threshold power of 21 mW. The fiber laser also achieved an optical signal-to-noise ratio of 80 dB, a beam quality factor of 1.022 in two orthogonal directions and a slope efficiency of up to 50.5%. These results indicate that the all-fiber DBR laser has potential applications in high-quality seed sources and coherent optical communications.

20.
Bioorg Med Chem Lett ; 30(9): 127097, 2020 05 01.
Article in English | MEDLINE | ID: mdl-32171616

ABSTRACT

A series of novel rutaecarpine derivatives were synthesized and subjected to pharmacological evaluation as PDE5 inhibitors. The structure-activity relationships were discussed and their binding conformation and simultaneous interaction mode were further clarified by the molecular docking studies. Among the 25 analogues, compound 8i exhibited most potent PDE5 inhibition with IC50 values about 0.086 µM. Moreover, it also produced good effects against scopolamine-induced cognitive impairment in vivo. These results might bring significant instruction for further development of potential PDE5 inhibitors derived from rutaecarpine as a good candidate drug for the treatment of Alzheimer's disease.


Subject(s)
Alzheimer Disease/drug therapy , Cognitive Dysfunction/chemically induced , Cyclic Nucleotide Phosphodiesterases, Type 5/metabolism , Indole Alkaloids/chemistry , Phosphodiesterase 5 Inhibitors/chemical synthesis , Phosphodiesterase 5 Inhibitors/pharmacology , Quinazolines/chemistry , Animals , Cholinergic Antagonists/toxicity , Cognitive Dysfunction/drug therapy , Dose-Response Relationship, Drug , Mice , Models, Molecular , Molecular Structure , Morris Water Maze Test , Phosphodiesterase 5 Inhibitors/administration & dosage , Phosphodiesterase 5 Inhibitors/chemistry , Protein Conformation , Scopolamine/toxicity
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